Diagnostic Accuracy of Fecal Occult Blood Testing for Colorectal Neoplasia in a Tertiary Care Setting: A Prospective Study from Ethiopia

Diagnostic Accuracy of Fecal Occult Blood Testing for Colorectal Neoplasia in a Tertiary Care Setting: A Prospective Study from Ethiopia | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Diagnostic Accuracy of Fecal Occult Blood Testing for Colorectal Neoplasia in a Tertiary Care Setting: A Prospective Study from Ethiopia Muse Kedir Mohammed, Abate Bane Shewaye, Getu Mosisa Kebebew This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9313580/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract Background: Colorectal cancer (CRC) is a major health concern, and early detection reduces its burden. The fecal occult blood test (FOBT) is a non-invasive, cost-effective screening tool, but its accuracy varies by test type and tumor location. Colonoscopy is the gold standard but limited in resource-constrained settings like Ethiopia. This study evaluated the diagnostic performance of FOBT in detecting colorectal neoplastic lesions among patients undergoing colonoscopy in Addis Ababa, Ethiopia. Method : An institution-based, prospective cross-sectional study was conducted from August 1 to October 30, 2025, among 240 patients using consecutive sampling. Data on demographics, clinical factors, FOBT results, and colonoscopy findings were collected via structured interviews and Kobo Collect. Diagnostic accuracy of FOBT was assessed using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy with 95% confidence intervals. Analyses were performed using IBM SPSS version 27 and STATA version 14.2. Results: Of 240 participants, 30.4% had a positive guaiac-based FOBT (gFOBT). For any colorectal neoplastic lesion, gFOBT showed moderate sensitivity (46.2%) and specificity (70.5%), with a high NPV (95.8%), indicating strong ability to rule out significant neoplasia. Sensitivity was higher for distal lesions (75%) than proximal lesions (33.3%). For colorectal adenocarcinoma, gFOBT sensitivity was 60% with a very high NPV (98.8%). All neoplastic lesions occurred in high-risk patients, yielding consistently high NPVs (>97%), while PPVs remained low. Conclusion: In this Ethiopian tertiary-care setting, guaiac-based FOBT demonstrated limited sensitivity but moderate specificity and consistently high NPV for clinically significant colorectal neoplasia, especially adenocarcinoma. While insufficient as a standalone diagnostic test, gFOBT can serve as a triage and exclusion tool in low-risk patients, helping prioritize colonoscopy in resource-limited settings, whereas high-risk patients should undergo colonoscopy regardless of FOBT results. Colonoscopy fecal occult blood test diagnostic accuracy test colorectal cancer colonic polyps Figures Figure 1 Figure 2 Introduction Colorectal cancer (CRC) is a major global health concern and remains the third most commonly diagnosed malignancy and the second leading cause of cancer-related mortality worldwide(1). Recent global estimates continue to demonstrate a substantial disease burden, with CRC accounting for a significant proportion of cancer-related disability-adjusted life years(2, 3). The majority of CRC cases arise through the adenoma–carcinoma sequence, a multistep process that typically progresses over 10–15 years, thereby providing an important window for early detection and prevention (4). Early-stage CRC is often asymptomatic or presents with non-specific symptoms such as rectal bleeding, change in bowel habits, iron deficiency anemia, abdominal pain, or weight loss(5). Without timely detection, progression to advanced disease significantly reduces survival. Established risk factors include increasing age, family history of colorectal neoplasia, inflammatory bowel disease, diets high in red or processed meat, low fiber intake, obesity, smoking, alcohol use, and type 2 diabetes mellitus (6, 7). Fecal occult blood testing (FOBT) is widely used as a non-invasive and cost-effective screening modality. While guaiac-based FOBT (gFOBT) detects peroxidase activity of hemoglobin, fecal immunochemical tests (FIT) use antibodies specific to human hemoglobin and demonstrate superior diagnostic performance. Meta-analyses report pooled sensitivity and specificity for FIT of approximately 85% and 93%, respectively, for CRC detection (8). In symptomatic populations, pooled sensitivity may reach 90% with specificity of 87%, whereas in screening contexts sensitivity is slightly lower (~69%) but specificity remains high (~94%) (9). In contrast, gFOBT has considerably lower sensitivity (~31%) with specificity around 87% (10).Positive FOBT results require confirmatory colonoscopy, which remains the gold standard for diagnosis and therapeutic polypectomy (11). In high-income countries, strong associations between positive FOBT and the presence of colorectal neoplasia on colonoscopy have been consistently demonstrated (12). However, evidence from sub-Saharan Africa remains limited. A study from Yaoundé, Cameroon, reported FIT sensitivity of 82.3% and specificity of 63.9% among symptomatic patients, with high negative predictive value but modest positive predictive value(13). In Nigeria, FIT demonstrated sensitivity of 96% and specificity of 90% in a screening cohort (14). Despite these encouraging findings, African studies are few, often single-center, and heterogeneous in design, limiting generalizability (15) In Ethiopia, CRC incidence is increasing, particularly in urban centers. Population-based cancer registry data from Addis Ababa identified CRC as the third most common cancer (16). According to GLOBOCAN 2022, CRC ranks third nationally, accounting for 6,551 new cases and 4,863 deaths (2). Notably, approximately 83% of Ethiopian patients present at advanced stages, reflecting delayed diagnosis and limited screening implementation (17) Colonoscopy services remain constrained by cost, infrastructure, and workforce limitations, and Ethiopia currently lacks a national CRC screening program (18). Given these challenges, FOBT may represent a pragmatic and scalable triage tool to prioritize patients for colonoscopy in resource-limited settings. However, no published studies have evaluated the diagnostic accuracy of FOBT against colonoscopic findings in Ethiopian tertiary care settings. The absence of locally generated evidence limits context-specific policy decisions and optimal allocation of scarce endoscopic resources (19). Therefore, this study aimed to evaluate the diagnostic accuracy of fecal occult blood testing for detecting colorectal neoplastic lesions among patients undergoing colonoscopy at tertiary hospitals in Addis Ababa, Ethiopia. Materials and Methods Study design, period and setting An institution-based prospective cross-sectional diagnostic accuracy study was conducted between August 1, 2025, and October 30, 2025, at two tertiary care centers in Addis Ababa, Ethiopia: Tikur Anbessa Specialized Hospital and Adera Medical and Surgical Center. Tikur Anbessa Specialized Hospital (TASH) is the largest tertiary referral and teaching hospital in Ethiopia, serving more than 500,000 patients annually with approximately 700 inpatient beds. The Department of Internal Medicine includes a gastroenterology and hepatology unit that provides diagnostic and therapeutic endoscopic and colonoscopic services. Patients are referred nationwide for evaluation of gastrointestinal symptoms, suspected colorectal cancer, and positive screening results (20, 21) Adera Medical and Surgical Center is a multispecialty private referral center located in Addis Ababa, with a strong focus on gastroenterology, hepatology, and advanced endoscopic services. The center is equipped with video colonoscopy systems, upper gastrointestinal endoscopy, a fully automated clinical laboratory, Doppler ultrasound, and CT scanning facilities. Both centers serve as major referral sites for colorectal disease evaluation and management (22). Study Population Source population; All adult patients (≥18 years) who underwent a Faecal Occult Blood Test (FOBT) and subsequently underwent a colonoscopy for further evaluation at in Addis Ababa, Ethiopia, during the study period. Study population: All consequentially selected, eligible adult patients (≥18 years) who underwent a Faecal Occult Blood Test (FOBT) and subsequently underwent a colonoscopy for further evaluation at Tikur Anbessa Specialized Hospital or Adera Medical and Surgical Center, Addis Ababa, Ethiopia, during the study period. Eligibility criteria Adult patients aged 18 years or older who underwent fecal occult blood testing (FOBT) for clinical evaluation or screening and subsequently underwent colonoscopy within four weeks at either participating center were eligible for inclusion. Participants were required to have no prior history of colorectal cancer or colonic resection and to provide written informed consent before enrolment. Patients were excluded if they had a previously established diagnosis of inflammatory bowel disease (ulcerative colitis or Crohn’s disease), known hemorrhoids with active rectal bleeding, or recent upper or lower gastrointestinal bleeding within two weeks prior to FOBT sample collection. Individuals with a history of bowel resection, previously identified colorectal mass or suspicious lesion on imaging, or those who had used nonsteroidal anti-inflammatory drugs, aspirin, or anticoagulants within 72 hours before FOBT were also excluded. In addition, participants who had consumed iron supplements or red meat within 72 hours prior to testing (for guaiac-based FOBT) were excluded. Patients who were unable or unwilling to provide informed consent were not included in the study. Sample size determination and sampling technique The sample size was calculated using Buderer’s formula for diagnostic test evaluation based on expected sensitivity, specificity, and disease prevalence. In the absence of local data, estimates were derived from a study conducted in Cameroon, which reported a sensitivity of 82.3%, specificity of 63.9%, and a prevalence of colorectal neoplasia of 31.1%. Assuming a 95% confidence level (Z = 1.96) and a precision of 10%, the minimum required sample size was 218 participants based on sensitivity and 201 based on specificity. After accounting for a 10% non-response rate, the final sample size was set at 240 participants. A consecutive sampling technique was employed. All eligible adult patients who underwent fecal occult blood testing (FOBT) followed by colonoscopy at either study center during the study period were consecutively recruited until the required sample size was achieved. Colonoscopy was performed within four weeks of FOBT to ensure temporal comparability between the index test and the reference standard(23, 24). Study Variables and measurements In this study, the fecal occult blood test (FOBT) served as the index test, while colonoscopy was considered the reference standard for determining the presence of colorectal neoplastic lesions. The primary outcome measure was the diagnostic performance of FOBT compared with colonoscopy findings. Diagnostic accuracy parameters included sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy. The principal independent variable was the FOBT result, categorized as positive or negative. Colonoscopic findings were recorded and classified as neoplastic (including mass-forming lesions, polyps, or ulcerated lesions suspicious for malignancy) or non-neoplastic. Where available, histopathological results were used to confirm tumor histology. Tumor-related characteristics, including anatomical location, lesion size, and histological type, were documented. Sociodemographic variables collected included age, sex, marital status, place of residence, educational status, and income level. Clinical presentation variables included history of rectal bleeding within two weeks prior to FOBT, abdominal pain, change in bowel habits, unintentional weight loss, anemia, and family history of colorectal cancer. Participants were further categorized as symptomatic or asymptomatic (routine colorectal screening). Laboratory parameters, including hemoglobin level and platelet count, were also recorded at the time of evaluation. The procedure of occult blood test Although both guaiac-based fecal occult blood test (gFOBT) and fecal immunochemical test (FIT) were initially planned, only the guaiac-based FOBT (gFOBT) was available at the study centers. Participants were instructed to avoid red or raw meat, iron supplements, NSAIDs, aspirin, and anticoagulants for at least three days prior to sample collection. Patients submitted stool samples directly to the central laboratory at each study site on the same day, and samples were stored at room temperature until analysis. Laboratory personnel performed the test according to the manufacturer’s instructions, interpreting results as positive if any color change occurred on the test card, indicating the presence of occult blood, or negative if no color change was observed. Internal quality control measures were implemented to ensure accuracy and consistency. The data recorded for each participant included the date of the FOBT, type of FOBT used (guaiac), and the test result (positive or negative). Guaiac-based FOBT was chosen because it is widely available, cost-effective, and suitable for screening in resource-limited settings. Colonoscopic examination Colonoscopy served as the reference standard for the detection and characterization of colorectal lesions. It was performed by trained gastroenterologists and senior gastroenterology fellows using high-resolution video colonoscopes (Fujinon) The procedure included visualization from the rectum to the cecum with photo documentation, identification and description of any lesions such as masses, polyps, ulcers, or bleeding, and biopsy or polypectomy when indicated, with samples sent for histopathological confirmation. For each colonoscopy, data collected included the date and completeness of the procedure, bowel preparation quality based on the Boston bowel preparation scale, the number, location, size, and morphology of lesions, suspected or confirmed diagnoses (e.g., adenoma, carcinoma, colitis, hemorrhoids), and histopathology results if applicable. Lesions were classified by type (polyp, colorectal cancer, diverticula, colitis, normal, or other), location (rectum, sigmoid, descending, transverse, ascending, cecum), and size in millimeters where applicable. Operational definitions A colorectal neoplastic lesion: was defined as rectal or colonic finding classified as advanced adenoma or non-advanced adenoma or colorectal cancer Non neoplastic lesion: was defined as rectal or colonic findings identified on colonoscopy that lack malignant or pre-malignant potential. These include hyperplastic polyps, Lymphoid hyperplasia, Angiodysplasia, lipomas, inflammatory polyps, diverticulosis, colitis without neoplasia and non-specific mucosal changes like erythema, edema, or granularity without definitive pathology(25, 26). Risk stratification Patients were classified into high-risk and low-risk groups based on clinical features associated with colorectal neoplasia. Patients were categorized as high-risk if they had at least one of the following: rectal bleeding, iron-deficiency anemia, unexplained weight loss, positive family history of colorectal cancer, or previous history of colorectal polyps. Patients without any of these features were classified as low-risk. This classification was generated using variable transformation and was used for stratified analysis of FOBT diagnostic performance. Data collection and quality assurance Data were collected using a structured digital questionnaire developed on the Kobo Collect platform. The questionnaire was developed specifically for this study based on the study objectives and relevant literature, and the English version is provided as Supplementary File 1. The tool captured sociodemographic characteristics, clinical presentation, comorbidities, FOBT results (positive/negative), colonoscopy findings, and lesion characteristics including location, size, and histological type. Eligible adult patients scheduled for colonoscopy at Tikur Anbessa Specialized Hospital and Adera Medical and Surgical Center were consecutively recruited after providing written informed consent. Sociodemographic and clinical information were obtained through face-to-face interviews using the structured questionnaire, while stool samples were collected and processed according to standard laboratory procedures. Colonoscopy was performed within four weeks of FOBT by experienced endoscopists, and suspicious lesions were biopsied for histopathological confirmation. Colonoscopic findings were cross-checked against histopathology reports to ensure the reliability of the reference standard. To ensure data quality, a pretest was conducted on 5% of the sample two weeks prior to the study among individuals with similar characteristics who were not included in the final analysis. Two trained general practitioners served as data collectors after receiving training on study procedures, ethical conduct, and use of the digital tool. Data were reviewed daily for completeness and consistency, and the principal investigator conducted routine supervision and random verification of records to ensure adherence to the study protocol. Data analysis methods Data collected using the Kobo Collect tool was cleaned and exported to IBM SPSS version 27 for analysis. Descriptive statistics was performed, categorical variables were summarized using frequencies and percentages, while continuous variables were presented as mean with standard deviation if normally distributed or median with interquartile range if not. Diagnostic Performance Analysis with their95% CI (sensitivity, specificity, NPV, PPV and accuracy) was calculated using STATA statistical software version 14.2. Findings were presented using tables, graphs, and charts for clarity, with key results summarized narratively and interpreted with existing literature. Results Socio-Demographic Characteristics of the Study Participants A total of 240 participants were included, yielding a 100% response rate. The mean age was 43.8 ± 15.1 years, with minimum of 18 year and maximum of 88 years, of these the majority (60.8%) aged 18–45 years. Most participants were recruited from Adera Medical and Surgical Center 219(91.3%), with the remainder from Tikur Anbessa Specialized Hospital 21(8.8%). The study population showed a male predominance, with 151(62.9%) and 89(37.1%) females. Most participants resided in urban areas204 (85.0%) and were married 176(73.3%). Regarding educational status, 104(43.3%) had college-level education or above, while 71(29.6%) completed grades 9–12. Occupationally, private-sector employees 63(26.3%) and government employees 50(20.8%) were the most common, followed by merchants 42(17.5%) and housewives 38(15.8%). The majority of participants reported a monthly income greater than 7,000 Ethiopian Birr141(58.8%), while 78(32.5%) earned 3,000–7,000 Birr and 21(8.8%) earned less than 3,000 Birr. See (Table -1) and additional sociodemographic variables are provided in Supplementary Table S1. Table 1 Sociodemographic characteristics of study participants Variables Category Frequency Percent (%) Mean Hospital Adera Medical and Surgical center 219 91.3% Tikur Anbessa Specialized Hospital (TASH) 21 8.8% Sex Female 89 37.1% Male 151 62.9% Age category 18-45 years old 146 60.8% >45 years old 94 39.2% Mean age 43.84 Place of residence Rural 36 15.0% Urban 204 85.0% Marital status Divorced 5 2.1% Married 176 73.3% Single 44 18.3% Widowed 15 6.3% -[[] Clinical and Laboratory Characteristics of the Study Participants The majority of participants were symptomatic at presentation (87.9%), with abdominal pain (84.2%) and change in bowel habit (67.9%) being the most frequently reported symptoms. Only 12.1% underwent colonoscopy for asymptomatic colorectal cancer screening. Overall, 30.4% of participants had a positive FOBT, while 69.6% tested negative (Fig-1). Recent overt gastrointestinal bleeding was reported by a minority (14.2%), and iron deficiency anemia was uncommon (6.7%). Weight loss was reported in approximately one-quarter of participants (26.7%). A family history of colorectal cancer and prior colonic polyps were rare, reported in 1.7% and 5.0% of participants, respectively. Based on predefined clinical risk stratification, 135 (56.3%) patients were classified as low-risk and 105 (43.8%) as high-risk Common comorbidities included hypertension (17.9%), diabetes mellitus (10.0%), and liver disease (11.3%), while cardiovascular and cerebrovascular diseases were infrequent. Lifestyle risk factors were uncommon, with very low prevalence of smoking and alcohol consumption. All participants underwent guaiac-based FOBT, most commonly performed once prior to colonoscopy (85.8%). Mean laboratory values were within normal ranges, including hemoglobin (14.67 g/dL), mean corpuscular volume (85.98 fL), and platelet count (242.57 ×10⁹/L). See (Table -2) and additional detail clinical characteristics variables provided in Supplementary Table S2 Table 2 Clinical characteristics of study participants Variables Category Frequency Percent (%) Colorectal cancer screening without any symptom No 211 87.9% Yes 29 12.1% Blood in the stool ,2weeks prior to FOBT No 206 85.8% Yes 34 14.2% Weight loss No 176 73.3% Yes 64 26.7% Abdominal pain No 38 15.8% Yes 202 84.2% Bowel habit (diarrhea or constipation) No 77 32.1% Yes 163 67.9% Iron deficiency anemia No 224 93.3% Yes 16 6.7% Family history of colorectal cancer No 235 97.9% Unknown 1 0.4% Yes 4 1.7% History of colonic polyp No 228 95.0% Yes 12 5.0% Risk stratification Low risk 135 56.3 High risk 105 43.8% Colonoscopic finding distribution among study participants Most colonoscopies were performed for diagnostic indications 222(92.5%), while screening colonoscopies accounted for 18(7.5%). Bowel preparation quality was rated as excellent in 169(70.4%), good in 60(25.0%), and poor in 11(4.6%). Cecal intubation was achieved in 205(85.4%) procedures. Abnormal colonoscopic findings were identified in 141(58.8%) patients, whereas 99(41.3%) had normal examinations. Among abnormal findings, other morphological lesions were most frequent 60(42.6%), followed by inflammatory lesions 39(27.7%), polyps 30(21.3%), mass-forming lesions 8(5.7%), and ulcerated lesions 4(2.8%). Within the “other” category, hemorrhoids were predominant 43(71.7%). Most polyps were non-pedunculated 28(93.3%), while pedunculated polyps were uncommon 2(6.7%). Colonoscopic findings suspicious for colorectal cancer were observed in 9(6.4%) patients. Lesions were most commonly located in the rectum 65(46.1%), followed by the ascending colon 23(16.3%), sigmoid colon 17(12.1%), and ileum 15(10.6%). Distal lesions 82(58.2%) were more frequent than proximal lesions 59(41.8%). Lesions measuring ≥10 mm were identified in 16(11.3%), while 18(12.8%) measured <10 mm. See table-3 and detail of colonoscopic finding provided in Supplementary Table S3 Table 3 Distribution of colonoscopic findings among study participants Variables Category Frequency Percent (%) Colonoscopy findings morphology Inflammatory 39 27.7% Mass forming lesion 8 5.7% Others Specify 60 42.6% Polyp 30 21.3% Ulcerated lesion 4 2.8% Other specified colonoscopic findings Aphthous ulcer 1 1.7% Diverticulosis 4 6.7% Hemorrhoids 43 71.7% parasitic infection 2 3.3% Spastic colon 9 15.0% Volvulus 1 1.7% Classification of lesion based on location Distal 82 58.2% Proximal 59 41.8% Histopathologic findings among biopsied patients Histopathologic results were analysed using biopsied patients as the denominator to ensure accurate estimation of tissue confirmed diagnoses. Among the biopsied patients (n = 80), non-specific colitis was the predominant histopathologic finding 41 (51.2%), followed by lymphoid hyperplasia 11 (13.8%). Colorectal adenocarcinoma was identified in 5 (6.3%) patients. (Table -4) Table 4 Histopathologic findings among biopsied lesions Frequency Percent (%) Biopsy No 160 66.7% Yes 80 33.3% Histopathologic diagnosis Colorectal adenocarcinoma 5 6.3% Hyperplastic polyp 6 7.5% Lymphoid hyperplasia 11 13.8% Non-specific colitis 41 51.2% Normal colonic histology 3 3.8% Others (specify) 8 10.0% Tubular adenoma 6 7.5% Other specified histopathology diagnosis chronic active proctitis 1 12.5% Glandular intraepithelial neoplasia 1 12.5% inflammatory polyp 5 62.5% Undifferentiated malignant tumor 1 12.5% Comparison of Colonoscopic and Histopathologic Findings by Fecal Occult Blood Test (FOBT) Result Among patients with abnormal colonoscopic findings, morphological patterns differed by FOBT result. In the FOBT-negative group, the most common findings were other lesions 44(45.4%), followed by inflammatory lesions 25(25.8%) and polyps 23(23.7%), while mass-forming lesions 3(3.1%) and ulcerated lesions 2(2.1%) were less frequent. In the FOBT-positive group, other lesions 16(36.4%) and inflammatory lesions 14(31.8%) predominated, with a higher proportion of mass-forming lesions 5(11.4%) compared to the FOBT-negative group. Findings suspicious for colorectal cancer were uncommon in FOBT-negative patients 2(2.1%), but were more frequent among FOBT-positive patients 7(15.9%). Distal lesions were more common in FOBT-negative patients 60(61.9%), whereas lesion distribution was equal between distal and proximal locations in FOBT-positive patients 22(50.0%) each. Biopsy was performed in 54(32.3%) FOBT-negative and 26(35.6%) FOBT-positive patients. The most frequent histopathologic diagnosis in both groups was non-specific colitis 28(51.9%) vs 13(50.0%), followed by lymphoid hyperplasia and hyperplastic polyps. Colorectal adenocarcinoma was identified more commonly in FOBT-positive patients 3(11.5%) than in FOBT-negative patients 2(3.7%). Fig-2 Low-grade dysplasia was observed in 3(5.6%) FOBT-negative and 3(11.5%) FOBT-positive patients, while high-grade dysplasia was rare 1(1.9%), occurring only in the FOBT-negative group. Overall, non-neoplastic lesions constituted the majority of final diagnoses in both FOBT-negative 160(95.8%) and FOBT-positive 67(91.8%) patients, whereas advanced neoplasia was more frequent in the FOBT-positive group 4(5.5%) compared to the FOBT-negative group 3(1.8%). See detail of FOBT result distribution among colonoscopic and histologic finding provided in Supplementary Table S4 Diagnostic Accuracy of the Fecal Occult Blood Test Overall, FOBT demonstrated limited diagnostic performance for general colorectal abnormalities and polyps, but moderate utility for neoplastic lesions, particularly advanced neoplasia and adenocarcinoma. For altered colonoscopic findings (prevalence 58.8%), FOBT showed low sensitivity (31.2%) with moderate specificity (70.7%), indicating poor ability to detect non-specific mucosal abnormalities. Similarly, diagnostic yield for polyps was low (overall sensitivity 23.3%), irrespective of lesion location. When stratified by clinical risk category, FOBT showed similarly low sensitivity for altered colonoscopic findings in both low-risk (32.9%) and high-risk patients (29.2%), with moderate specificity in both groups. This suggests limited utility of FOBT for detecting non-neoplastic abnormalities regardless of baseline clinical risk. In contrast, FOBT demonstrated better performance for neoplastic lesions. For any colorectal neoplasia (overall prevalence 5.4%), sensitivity was 46.2% with a high negative predictive value (95.8%), supporting its role as a rule-out test. Diagnostic performance was superior for distal neoplasia compared with proximal lesions (sensitivity 75% vs 33.3%). Importantly, all neoplastic lesions, including advanced neoplasia and adenocarcinoma, were observed exclusively in the high-risk group. As a result, diagnostic accuracy parameters for neoplastic outcomes could not be calculated for low-risk patients. Among high-risk patients, FOBT demonstrated moderate sensitivity for any neoplasia (60%) and advanced neoplasia (57.1%), with consistently high NPVs (>94%). Detection of adenocarcinoma in the high-risk group showed a sensitivity of 60% and an NPV of 97.3%. Positive predictive values remained low across all outcomes, underscoring the need for confirmatory colonoscopy following a positive FOBT. Overall, FOBT has limited value for detecting polyps and non-neoplastic abnormalities, but demonstrates moderate diagnostic accuracy for clinically significant neoplasia, particularly in high-risk patients, supporting its use as a triage and exclusion tool rather than a definitive diagnostic test. See Table- 6 and Detailed subgroup analysis of diagnostic performance test are provided in Supplementary Table S5 . Table 5 FOBT diagnostic performance for colorectal neoplasia in Addis Ababa, Ethiopia Lesion Lesion location Prevalence (%) u Sensitivity Specificity PPV NPV Accuracy % 95%CI % 95%CI % 95% CI % 95%CI % 95% CI Altered colonoscopic finding 58.8 31.2 23.7-39.5 70.7 60.7 -79.4 60.3 48.1 - 71.5 41.9 34.3-49.8 47.5 1.04 -54.02 Any Neoplastic lesion 5.4 46.2 19.2 - 74.9 70.5 64.1 - 76.3 8.2 3.1 - 17.0 95.8 91.6 - 98.3 69.2 62.90 -74.95 Any polyp 12.5% 23.3 9.9 - 42.3 68.6 61.8 - 74.8 9.6 3.9 - 18.8 86.2 80.1 - 91.1 62.9 56.47- 69.04 Advanced neoplasia 2.9 57.1 18.4 - 90.1 70.4 64.1 - 76.2 5.5 1.5 - 13.4 98.2 94.8 - 99.6 70 63.77 - 75.73 Non advanced neoplasia 2.5 33.3 4.3 - 77.7 69.7 63.3 -75.5 2.7 0.3 - 9.5 97.6 94.0 - 99.3 68.8 62.47 -74.56 Tubular adenoma 2.5 33.3 4.3 - 77.7 69.7 63.3 -75.5 2.7 0.3 - 9.5 97.6 94.0 - 99.3 68.9 62.47-74.56 Adenocarcinoma 2.1 60 14.7 - 94.7 70.2 63.9 - 76.0 4.1 0.9 - 11.5 98.8 95.7- 99.9 70 63.77 -75.73 Discussion This hospital-based cross-sectional study evaluated the diagnostic performance of the guaiac-based fecal occult blood test (FOBT) in detecting colorectal neoplastic lesions. The findings provide important insights into the utility and limitations of FOBT in the Ethiopian clinical context, where colonoscopy access remains limited. The study population had a mean age of 43.8 years, younger than typical colorectal screening cohorts in high-income countries, where average screening age is above 50 years. This reflects the diagnostic nature of colonoscopy use in Ethiopia, where patients present earlier due to symptoms rather than structured screening programs(27). Similarly, limited evidence from sub-Saharan Africa indicates that colorectal cancer often presents in younger age groups and at more advanced stages compared with high-income countries. Given the region’s shorter life expectancy (approximately 50–60 years), the conventional screening age of 50 years used in Western countries may not be realistic. Additionally, most countries in this region lack nationwide CRC screening protocols, which likely contributes to delayed diagnosis and younger symptomatic presentation(28-30). In our cohort men comprised 59.2% of participants. This male predominance is consistent with findings from a large outreach colonoscopy series in Southwest Ethiopia, which reported a predominantly male cohort (70.6%) with a mean age of 44 years and the majority under 50. The similar male skew in these Ethiopian series may reflect local referral patterns, symptomatic presentation among working-age men, or differential access to endoscopy services rather than true population prevalence of colorectal disease(31). In our two-center study, the overall cecal intubation rate (CIR) was 84.5%. International quality benchmarks recommend a cecal intubation rate of ≥90% for all colonoscopies and ≥95% for screening colonoscopies. Compared with these standards, the CIR in our study is lower than the recommended targets.(32, 33). However, when interpreted in the context of real-world practice, our findings are comparable to several observational studies, particularly those conducted outside high-volume tertiary academic centers. Studies from routine clinical practice, especially in mixed-indication colonoscopy populations, have reported CIRs ranging from 77% to 89%, which overlaps with our result. Lower completion rates in such settings have been attributed to factors including variable bowel preparation quality, patient comorbidities, complex colonic anatomy, and limited procedural support(34-36). Abnormal colonoscopic findings were common in both FOBT-positive and negative groups (≈59% overall). Inflammatory conditions and hemorrhoids were the most frequent abnormality, consistent with prior Ethiopian studies showing a high burden of non-neoplastic gastrointestinal diseases(31, 37). Polyps accounted for approximately 20% of lesions, while mass-forming lesions and colonoscopic suspicion of malignancy were noticeably more frequent among FOBT-positive participants, reflecting the biological link between bleeding and advanced lesions. Lesion distribution showed a predominance of distal involvement, particularly rectal lesions, which represented nearly half of abnormal findings. This pattern is consistent with African and Asian studies reporting a distal shift in colorectal lesions compared with Western populations(38). Histology confirmed that most biopsied lesions were non-neoplastic, with non-specific colitis being the dominant finding. Adenocarcinoma prevalence (2.1%) was low but higher among FOBT-positive participants. Advanced neoplasia was also more frequent in the FOBT-positive group (5.5% vs. 1.8%), supporting the potential rule-in value of FOBT for significant pathology. This finding with consistent with recent study from south west Ethiopia however prevalence of adenocarcinoma in our study is lower which is likely from lower sample size (31). In the present study, FOBT demonstrated moderate sensitivity (46.2%) and specificity (70.5%) for the detection of any colorectal neoplasia, with an excellent negative predictive value (NPV) of 95.8%. This finding indicates that a negative FOBT result is useful for ruling out colorectal neoplasia, particularly in populations with a low prevalence of disease. Similar high NPVs have been reported in prior studies, ranging from 95.4% for guaiac-based FOBT and 97.5% for fecal immunochemical testing (FIT) in screening populations, and increasing to 98.99% and 99.56%, respectively, in hospital-based settings (39, 40). The sensitivity of gFOBT observed in this study is comparable to values reported in meta-analyses, where sensitivity for neoplasia detection varies widely from as low as 6% to approximately 46% in cohort-based settings (41). However, the specificity observed in this study (approximately 70%) is lower than that reported in many population-based screening studies, which often demonstrate specificities exceeding 80%(42). These discrepancies may be attributable to differences in study design, patient selection, testing protocols, and sample size, all of which can substantially influence diagnostic accuracy estimates. FOBT performance varied according to lesion location. Sensitivity for distal neoplastic lesions reached 75%, whereas sensitivity for proximal lesions was markedly lower (33.3%). This pattern is consistent with established evidence that FOBT preferentially detects bleeding from left-sided lesions due to shorter intestinal transit time and reduced hemoglobin degradation. Meta-analyses have similarly demonstrated higher sensitivity for distal compared with proximal colorectal cancer, with pooled estimates of approximately 80.1% versus 71.2%, respectively(43). Comparable trends have been reported for FIT, with significantly higher pooled sensitivities for distal advanced neoplasia compared to proximal disease (40). Notably, gFOBT demonstrated higher sensitivity for clinically significant lesions in this cohort, with sensitivities of 57.1% (95% CI: 18.4–90.1) for advanced neoplasia and 60% (95% CI: 14.7–94.7) for colorectal adenocarcinoma, along with very high NPVs (>98%) for both outcomes. These values exceed those typically reported in average-risk screening populations, where sensitivity for advanced neoplasia generally ranges from the low tens to low 30% and sensitivity for colorectal cancer ranges from approximately 25% to 38% when colonoscopy is used as the reference standard(41, 44). The relatively higher sensitivities observed in this study likely reflect the symptomatic nature of the study population and the higher pre-test probability of clinically significant disease. Importantly, patients in this study were further stratified into high-risk and low-risk groups based on predefined clinical criteria, including rectal bleeding, iron deficiency anemia, unexplained weight loss, family history of colorectal cancer, and prior history of colorectal polyps. All detected neoplastic lesions occurred within the high-risk group, resulting in zero neoplasia events among low-risk patients. Consequently, diagnostic performance metrics such as sensitivity and positive predictive value could not be calculated for the low-risk subgroup due to the absence of outcome events. This finding is not a methodological limitation but rather reflects the strong discriminative value of clinical risk stratification in this cohort. These results underscore that FOBT should not be used to exclude colonoscopy in high-risk symptomatic patients, even when FOBT results are negative. In contrast, among low-risk patients without alarm features, the absence of neoplasia combined with the high NPV of FOBT supports its potential role as a triage tool to safely defer or prioritize colonoscopy in resource-limited settings. This approach aligns with international recommendations, which consistently emphasize that alarm features and high-risk clinical characteristics should prompt colonoscopic evaluation regardless of stool test results(45). However, in our study gFOBT done one times in majority of patients as result it may be appropriate to repeat FOBT before deferring colonoscopy even in low-risk patients. Despite the relatively higher sensitivities observed in this study, large comparative analyses consistently demonstrate that fecal immunochemical tests outperform guaiac-based FOBT, with reported sensitivities of approximately 33% versus 15% for advanced neoplasia and 76% versus 39% for colorectal cancer, respectively(41). Therefore, while gFOBT may have utility as a triage and exclusion tool in selected settings, FIT remains the preferred non-invasive stool-based test where available. Taken together, the findings of this study suggest that gFOBT has limited utility for detecting non-neoplastic and polypoid lesions but demonstrates moderate diagnostic accuracy for clinically significant neoplasia, particularly advanced lesions. When combined with careful clinical risk stratification, FOBT may serve as a pragmatic triage tool in symptomatic patients, especially in resource-constrained environments. However, colonoscopy remains mandatory for high-risk patients irrespective of FOBT results. Strengths and limitations of the Study This study has several key strengths. Its prospective design with standardized assessments minimized bias and allowed accurate comparison between FOBT and colonoscopy findings. The use of colonoscopy with histopathology as the reference standard ensured reliable classification of colorectal lesions, while consecutive sampling in tertiary hospitals enhanced real-world applicability in a resource-limited setting. Furthermore, detailed lesion characterization and clinical risk stratification enabled meaningful subgroup analyses, improving the clinical relevance of the findings. Despite these strengths, several limitations should be noted. The study was conducted among symptomatic patients in tertiary centers, limiting generalizability to population-based screening. Use of a single guaiac-based FOBT may have underestimated diagnostic performance compared with repeated testing or fecal immunochemical testing. The small number of neoplastic cases in some subgroups reduced the precision of estimates, and the absence of neoplasia in low-risk patients prevented calculation of some diagnostic metrics. Finally, as the study was conducted in a resource-limited tertiary setting, findings may not fully apply to primary care or higher-resource healthcare environments. Conclusion FOBT demonstrated limited sensitivity for non-neoplastic lesions and polyps but moderate diagnostic accuracy for clinically significant colorectal neoplasia, particularly advanced neoplasia and adenocarcinoma, with high negative predictive value. All neoplastic lesions were identified in high-risk symptomatic patients, underscoring the critical role of clinical risk stratification. Accordingly, colonoscopy remains mandatory for high-risk patients regardless of FOBT results. In contrast, among low-risk symptomatic patients without alarm features, FOBT may serve as a pragmatic triage tool to prioritize colonoscopy in resource-limited settings. Strengthening clinician adherence to risk stratification, implementing structured referral and follow-up systems, and integrating risk-stratified FOBT use into national colorectal cancer strategies are recommended to optimize resource allocation. Where feasible, fecal immunochemical testing (FIT) should be adopted given its superior sensitivity. Future research should evaluate FIT-based strategies in population settings, assess cost-effectiveness of stool-based triage versus direct colonoscopy referral, and refine combined clinical and stool-based risk models to improve early detection while conserving limited endoscopy capacity. Abbreviations CIR: Cecal Intubation Rate CRC Colorectal Cancer FOBT Fecal Occult Blood Test gFOBT Guaiac-based Faecal Occult Blood Test FIT Faecal I mmunochemical Test MCV Mean Corpuscular Volume NPV Negative Predictive Value NSAID Non-steroidal Anti-inflammatory Drugs PLT Platelet PPV Positive Predictive Value TASH Tikur Anbessa Specialized Hospital Declarations Ethics approval and consent to participate Ethical approval was obtained from the Institutional Review Board (IRB) of Addis Ababa University, College of Health Sciences , Internal Medicine Department review board with protocol number 14/25 and Meeting number 07/25 on 23/05/2025. The study was conducted in accordance with the ethical principles of the declaration of Helsinki. Consent for publication Not applicable Availability of data and materials The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. Competing interests The authors declare no competing interests. Funding Authors states that they did not receive any fund for the study nor for the publication. Authors' contributions MK conceived and designed the study, performed data collection, conducted the statistical analysis, and drafted the manuscript. AB critically reviewed the manuscript for important intellectual content. GM contributed to the study methodology and provided methodological oversight Acknowledgements We would like to express our sincere gratitude to Addis Ababa University, College of Health Sciences, for allowing us to conduct this study. References Sung H, Ferlay J, Siegel RL, Laversanne M, Soerjomataram I, Jemal A, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin. 2021;71(3):209-49. doi: {10.3322/caac.21660} Bray F, Laversanne M, Sung H, Ferlay J, Siegel RL, Soerjomataram I, et al. 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Adera Medical and surgical center In: solutions HI, editor. Addis Ababa ,Ethiopia https://aderamedicalcenter.com/; 2025. Jovanka TU, Wilson NNA, Winnie BN, Paule NM, Paul T, Isabelle DB, et al. Predictive values of an immunological fecal occult blood test for the diagnosis of colorectal cancer compared using colonoscopy in symptomatic patients in Yaounde (Cameroon). BMC Gastroenterol. 2024;24(1):198. doi: {10.1186/s12876-024-03292-x} Negida A, Fahim NK, Negida Y. Sample Size Calculation Guide - Part 4: How to Calculate the Sample Size for a Diagnostic Test Accuracy Study based on Sensitivity, Specificity, and the Area Under the ROC Curve. Adv J Emerg Med. 2019;3(3):e33. doi: {10.22114/ajem.v0i0.158} Lieberman DA, Rex DK, Winawer SJ, Giardiello FM, Johnson DA, Levin TR. Guidelines for Colonoscopy Surveillance After Screening and Polypectomy: A Consensus Update by the US Multi-Society Task Force on Colorectal Cancer. Gastroenterology. 2012;143(3):844-57. doi: {10.1053/j.gastro.2012.06.001} Rutter MD, Chattree A, Barbour JA, Thomas-Gibson S, Bhandari P, Saunders BP, et al. British Society of Gastroenterology/Association of Coloproctologists of Great Britain and Ireland guidelines for the management of large non-pedunculated colorectal polyps. Gut. 2015;64(12):1847-73. doi: {10.1136/gutjnl-2015-309576} Force UPST. Screening for Colorectal Cancer: US Preventive Services Task Force Recommendation Statement. JAMA. 2021;325(19):1965-77. doi: {10.1001/jama.2021.6238} Kwakye G, Dally CK. Colorectal cancer screening in sub-Saharan Africa. The Lancet Global Health. 2022;10(7):e938-e9. doi: {10.1016/S2214-109X(22)00231-5} Matovu N, Coleman HG, Mesa-Eguiagaray I, Theodoratou E, McShane CM. The descriptive epidemiology of age at colorectal cancer diagnosis in Africa: a systematic review and meta-analysis. eClinicalMedicine. 2025;88:103445. doi: {https://doi.org/10.1016/j.eclinm.2025.103445} Organization WH. Health and well-being for all in the WHO African Region: a summary. Retrieved on; 2024. Roro GM, Roro EM, Abebe DM. Addressing gastrointestinal disorders in rural Ethiopia: Success of a weekend outreach colonoscopy service. World J Gastrointest Endosc. 2025;17(9):110476. doi: {10.4253/wjge.v17.i9.110476} Vemulapalli KC, Wilder SW, Kahi CJ, Rex DK. Long-Term Assessment of the Cecal Intubation Rates in High-Performing Colonoscopists: Time for Review. Clin Transl Gastroenterol. 2020;11(3):e00153. doi: {10.14309/ctg.0000000000000153} Fernandes C, Estevinho M, Marques Cruz M, Frazzoni L, Rodrigues PP, Fuccio L, et al. Adenoma detection rate by colonoscopy in real-world population-based studies: a systematic review and meta-analysis. Endoscopy. 2024;57(01):49-61. doi: {10.1055/a-2382-5795} Muslim OT, Al-Obaidi HO. Cecal and ilial intubation rates in colonoscopy: Comparative study. J Popul Ther Clin Pharmacol. 2021;28(2):e1-e6. doi: {10.47750/jptcp.2021.847} Gado AS, Ebeid BA, Abdelmohsen AM, Gado TS, Axon AT. Quality of colonoscopy practice: a single-center experience in Egypt. The Egyptian Journal of Internal Medicine. 2016;28(3):108-15. doi: {10.4103/1110-7782.200968} Park H-J, Hong J-H, Kim H-S, Kim B-R, Park S-Y, Jo K-W, et al. Predictive factors affecting cecal intubation failure in colonoscopy trainees. BMC Medical Education. 2013;13(1):5. doi: {10.1186/1472-6920-13-5} Gudissa FG, Alemu B, Gebremedhin S, Gudina EK, Desalegn H. Colonoscopy at a tertiary teaching hospital in Ethiopia: a five-year retrospective review. PAMJ Clinical Medicine. 2021;5(37). doi: Kebede AG, Kebede T, Atnafu A. High Magnitude Advanced Colorectal Cancer at Diagnosis in Ethiopian Patients: Imaging Pattern and Associated Factors. Ethiop J Health Sci. 2023;33(1):81-90. doi: {10.4314/ejhs.v33i1.11} Elsafi SH, Alqahtani NI, Zakary NY, Al Zahrani EM. The sensitivity, specificity, predictive values, and likelihood ratios of fecal occult blood test for the detection of colorectal cancer in hospital settings. Clin Exp Gastroenterol. 2015;8:279-84. doi: {10.2147/ceg.S86419} Parra-Blanco A, Gimeno-García AZ, Quintero E, Nicolás D, Moreno SG, Jiménez A, et al. Diagnostic accuracy of immunochemical versus guaiac faecal occult blood tests for colorectal cancer screening. J Gastroenterol. 2010;45(7):703-12. doi: {10.1007/s00535-010-0214-8} Grobbee EJ, Wisse PHA, Schreuders EH, van Roon A, van Dam L, Zauber AG, et al. Guaiac-based faecal occult blood tests versus faecal immunochemical tests for colorectal cancer screening in average-risk individuals. Cochrane Database Syst Rev. 2022;6(6):Cd009276. doi: {10.1002/14651858.CD009276.pub2} Katsoula A, Paschos P, Haidich A-B, Tsapas A, Giouleme O. Diagnostic accuracy of fecal immunochemical test in patients at increased risk for colorectal cancer: a meta-analysis. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9313580","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":636347517,"identity":"7bfb678f-f2b6-449d-8939-0fc79879ba5a","order_by":0,"name":"Muse Kedir Mohammed","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA5UlEQVRIie3RMQrCMBSA4SeBTFHXgvQIQkqgk/QsLQW76OTiKAidxFlB8Ao9QqBglx6gY7ro0iFubjVRxC3VTTD/kgzv4xECYLP9bBx6KSBO1bW3+oLg8EU+YVxPES0+IONdUgsoJ+52VMoFgYmbcVQIE/GrGaNQTVk6mGeMwJRlHEfGLYpgB2QepaSvSR5lnHgdJLncQLaKEKFIq8jw2kFCH6DimoAiXG8xP98vG+aEZcxSgql3oDHb59jbGUmR1FKeAve4QWfaLAN3W6yFNJFH4fPAFPTXoM75d0h8MWyz2Wx/1B3LOk2j1/XUggAAAABJRU5ErkJggg==","orcid":"","institution":"Jimma University","correspondingAuthor":true,"prefix":"","firstName":"Muse","middleName":"Kedir","lastName":"Mohammed","suffix":""},{"id":636347518,"identity":"399071a2-ca9c-4f7e-9a4f-35e6e717a63f","order_by":1,"name":"Abate Bane Shewaye","email":"","orcid":"","institution":"Addis Ababa University","correspondingAuthor":false,"prefix":"","firstName":"Abate","middleName":"Bane","lastName":"Shewaye","suffix":""},{"id":636347520,"identity":"ef96f6d5-08e8-421b-b40d-84da05bc6497","order_by":2,"name":"Getu Mosisa Kebebew","email":"","orcid":"","institution":"Wollega University","correspondingAuthor":false,"prefix":"","firstName":"Getu","middleName":"Mosisa","lastName":"Kebebew","suffix":""}],"badges":[],"createdAt":"2026-04-03 13:54:09","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9313580/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9313580/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":108968895,"identity":"65fbbf29-a6fb-4613-a4f2-580d9a94daa4","added_by":"auto","created_at":"2026-05-11 10:06:50","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":28829,"visible":true,"origin":"","legend":"\u003cp\u003eDistribution of fecal occult blood test results among study participants\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-9313580/v1/5f3eac7f28815310a8a7c7d9.png"},{"id":108968896,"identity":"3108aa98-2d66-41d0-9fde-4680864d7906","added_by":"auto","created_at":"2026-05-11 10:06:50","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":45229,"visible":true,"origin":"","legend":"\u003cp\u003eDistribution of histologic results by FOBT status in Addis Ababa, Ethiopia\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-9313580/v1/e3a26cac2b5f2ef4df20fed9.png"},{"id":108979736,"identity":"b11c429e-3745-48f7-8c7a-fa4b5477e31f","added_by":"auto","created_at":"2026-05-11 12:00:57","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":470548,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9313580/v1/1b58b806-b3c4-4ffb-9029-d02bb70ea8a6.pdf"},{"id":108977880,"identity":"41c1baf9-86bd-4ce0-a5a8-71f121a5fb0d","added_by":"auto","created_at":"2026-05-11 11:33:20","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":28497,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryFile1.StructuredQuestionnaireUsedforDataCollectionEnglishVersion.docx","url":"https://assets-eu.researchsquare.com/files/rs-9313580/v1/799b02f1ef85bec0a6a9ce3d.docx"},{"id":108968897,"identity":"8a71d2b3-1d8b-446f-ab50-0499186bd380","added_by":"auto","created_at":"2026-05-11 10:06:50","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":35590,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryTables.docx","url":"https://assets-eu.researchsquare.com/files/rs-9313580/v1/735775262e2a4e276b86770b.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Diagnostic Accuracy of Fecal Occult Blood Testing for Colorectal Neoplasia in a Tertiary Care Setting: A Prospective Study from Ethiopia","fulltext":[{"header":"Introduction","content":"\u003cp\u003eColorectal cancer (CRC) is a major global health concern and remains the third most commonly diagnosed malignancy and the second leading cause of cancer-related mortality worldwide(1). Recent global estimates continue to demonstrate a substantial disease burden, with CRC accounting for a significant proportion of cancer-related disability-adjusted life years(2, 3). The majority of CRC cases arise through the adenoma\u0026ndash;carcinoma sequence, a multistep process that typically progresses over 10\u0026ndash;15 years, thereby providing an important window for early detection and prevention (4). Early-stage CRC is often asymptomatic or presents with non-specific symptoms such as rectal bleeding, change in bowel habits, iron deficiency anemia, abdominal pain, or weight loss(5).\u003c/p\u003e\n\u003cp\u003eWithout timely detection, progression to advanced disease significantly reduces survival. Established risk factors include increasing age, family history of colorectal neoplasia, inflammatory bowel disease, diets high in red or processed meat, low fiber intake, obesity, smoking, alcohol use, and type 2 diabetes mellitus (6, 7). Fecal occult blood testing (FOBT) is widely used as a non-invasive and cost-effective screening modality. While guaiac-based FOBT (gFOBT) detects peroxidase activity of hemoglobin, fecal immunochemical tests (FIT) use antibodies specific to human hemoglobin and demonstrate superior diagnostic performance. Meta-analyses report pooled sensitivity and specificity for FIT of approximately 85% and 93%, respectively, for CRC detection (8).\u0026nbsp;In symptomatic populations, pooled sensitivity may reach 90% with specificity of 87%, whereas in screening contexts sensitivity is slightly lower (~69%) but specificity remains high (~94%)\u0026nbsp;(9).\u003c/p\u003e\n\u003cp\u003eIn contrast, gFOBT has considerably lower sensitivity (~31%) with specificity around 87% (10).Positive FOBT results require confirmatory colonoscopy, which remains the gold standard for diagnosis and therapeutic polypectomy (11).\u003c/p\u003e\n\u003cp\u003eIn high-income countries, strong associations between positive FOBT and the presence of colorectal neoplasia on colonoscopy have been consistently demonstrated (12). However, evidence from sub-Saharan Africa remains limited. A study from Yaound\u0026eacute;, Cameroon, reported FIT sensitivity of 82.3% and specificity of 63.9% among symptomatic patients, with high negative predictive value but modest positive predictive value(13).\u0026nbsp;In Nigeria, FIT demonstrated sensitivity of 96% and specificity of 90% in a screening cohort\u0026nbsp;(14).\u0026nbsp;Despite these encouraging findings, African studies are few, often single-center, and heterogeneous in design, limiting generalizability\u0026nbsp;(15)\u003c/p\u003e\n\u003cp\u003eIn Ethiopia, CRC incidence is increasing, particularly in urban centers. Population-based cancer registry data from Addis Ababa identified CRC as the third most common cancer (16).\u0026nbsp;According to GLOBOCAN 2022, CRC ranks third nationally, accounting for 6,551 new cases and 4,863 deaths\u0026nbsp;(2).\u0026nbsp;Notably, approximately 83% of Ethiopian patients present at advanced stages, reflecting delayed diagnosis and limited screening implementation\u0026nbsp;(17)\u003c/p\u003e\n\u003cp\u003eColonoscopy services remain constrained by cost, infrastructure, and workforce limitations, and Ethiopia currently lacks a national CRC screening program (18).\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGiven these challenges, FOBT may represent a pragmatic and scalable triage tool to prioritize patients for colonoscopy in resource-limited settings. However, no published studies have evaluated the diagnostic accuracy of FOBT against colonoscopic findings in Ethiopian tertiary care settings. The absence of locally generated evidence limits context-specific policy decisions and optimal allocation of scarce endoscopic resources (19).\u003c/p\u003e\n\u003cp\u003eTherefore, this study aimed to evaluate the diagnostic accuracy of fecal occult blood testing for detecting colorectal neoplastic lesions among patients undergoing colonoscopy at tertiary hospitals in Addis Ababa, Ethiopia.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eStudy design, period and\u0026nbsp;setting\u003c/p\u003e\n\u003cp\u003eAn institution-based prospective cross-sectional diagnostic accuracy study was conducted between August 1, 2025, and October 30, 2025, at two tertiary care centers in Addis Ababa, Ethiopia: Tikur Anbessa Specialized Hospital and Adera Medical and Surgical Center. \u0026nbsp;Tikur Anbessa Specialized Hospital (TASH) is the largest tertiary referral and teaching hospital in Ethiopia, serving more than 500,000 patients annually with approximately 700 inpatient beds. The Department of Internal Medicine includes a gastroenterology and hepatology unit that provides diagnostic and therapeutic endoscopic and colonoscopic services. Patients are referred nationwide for evaluation of gastrointestinal symptoms, suspected colorectal cancer, and positive screening results (20, 21) Adera Medical and Surgical Center is a multispecialty private referral center located in Addis Ababa, with a strong focus on gastroenterology, hepatology, and advanced endoscopic services. The center is equipped with video colonoscopy systems, upper gastrointestinal endoscopy, a fully automated clinical laboratory, Doppler ultrasound, and CT scanning facilities. Both centers serve as major referral sites for colorectal disease evaluation and management (22).\u003c/p\u003e\n\u003cp id=\"_Toc222660085\"\u003eStudy Population\u003c/p\u003e\n\u003cp id=\"_Toc222660086\"\u003eSource population;\u003c/p\u003e\n\u003cp\u003eAll adult patients (\u0026ge;18 years) who underwent a Faecal Occult Blood Test (FOBT) and subsequently underwent a colonoscopy for further evaluation at in Addis Ababa, Ethiopia, during the study period.\u003c/p\u003e\n\u003cp id=\"_Toc222660087\"\u003eStudy population:\u003c/p\u003e\n\u003cp\u003eAll consequentially selected, eligible adult patients (\u0026ge;18 years) who underwent a Faecal Occult Blood Test (FOBT) and subsequently underwent a colonoscopy for further evaluation at Tikur Anbessa Specialized Hospital or Adera Medical and Surgical Center, Addis Ababa, Ethiopia, during the study period.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eEligibility criteria\u003c/p\u003e\n\u003cp\u003eAdult patients aged 18 years or older who underwent fecal occult blood testing (FOBT) for clinical evaluation or screening and subsequently underwent colonoscopy within four weeks at either participating center were eligible for inclusion. Participants were required to have no prior history of colorectal cancer or colonic resection and to provide written informed consent before enrolment.\u003c/p\u003e\n\u003cp\u003ePatients were excluded if they had a previously established diagnosis of inflammatory bowel disease (ulcerative colitis or Crohn\u0026rsquo;s disease), known hemorrhoids with active rectal bleeding, or recent upper or lower gastrointestinal bleeding within two weeks prior to FOBT sample collection. Individuals with a history of bowel resection, previously identified colorectal mass or suspicious lesion on imaging, or those who had used nonsteroidal anti-inflammatory drugs, aspirin, or anticoagulants within 72 hours before FOBT were also excluded. In addition, participants who had consumed iron supplements or red meat within 72 hours prior to testing (for guaiac-based FOBT) were excluded. Patients who were unable or unwilling to provide informed consent were not included in the study.\u003c/p\u003e\n\u003cp id=\"_Toc222660093\"\u003eSample size\u0026nbsp;determination and sampling technique\u003c/p\u003e\n\u003cp\u003eThe sample size was calculated using Buderer\u0026rsquo;s formula for diagnostic test evaluation based on expected sensitivity, specificity, and disease prevalence. In the absence of local data, estimates were derived from a study conducted in Cameroon, which reported a sensitivity of 82.3%, specificity of 63.9%, and a prevalence of colorectal neoplasia of 31.1%. Assuming a 95% confidence level (Z = 1.96) and a precision of 10%, the minimum required sample size was 218 participants based on sensitivity and 201 based on specificity. After accounting for a 10% non-response rate, the final sample size was set at 240 participants.\u003c/p\u003e\n\u003cp\u003eA consecutive sampling technique was employed. All eligible adult patients who underwent fecal occult blood testing (FOBT) followed by colonoscopy at either study center during the study period were consecutively recruited until the required sample size was achieved. Colonoscopy was performed within four weeks of FOBT to ensure temporal comparability between the index test and the reference standard(23, 24).\u003c/p\u003e\n\u003cp id=\"_Toc128249558\"\u003eStudy Variables and measurements\u003c/p\u003e\n\u003cp\u003eIn this study, the fecal occult blood test (FOBT) served as the index test, while colonoscopy was considered the reference standard for determining the presence of colorectal neoplastic lesions. The primary outcome measure was the diagnostic performance of FOBT compared with colonoscopy findings. Diagnostic accuracy parameters included sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy. The principal independent variable was the FOBT result, categorized as positive or negative. Colonoscopic findings were recorded and classified as neoplastic (including mass-forming lesions, polyps, or ulcerated lesions suspicious for malignancy) or non-neoplastic. Where available, histopathological results were used to confirm tumor histology. Tumor-related characteristics, including anatomical location, lesion size, and histological type, were documented.\u003c/p\u003e\n\u003cp\u003eSociodemographic variables collected included age, sex, marital status, place of residence, educational status, and income level. Clinical presentation variables included history of rectal bleeding within two weeks prior to FOBT, abdominal pain, change in bowel habits, unintentional weight loss, anemia, and family history of colorectal cancer. Participants were further categorized as symptomatic or asymptomatic (routine colorectal screening). Laboratory parameters, including hemoglobin level and platelet count, were also recorded at the time of evaluation.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe procedure of occult blood test\u003c/p\u003e\n\u003cp\u003eAlthough both guaiac-based fecal occult blood test (gFOBT) and fecal immunochemical test (FIT) were initially planned, only the guaiac-based FOBT (gFOBT) was available at the study centers. Participants were instructed to avoid red or raw meat, iron supplements, NSAIDs, aspirin, and anticoagulants for at least three days prior to sample collection. Patients submitted stool samples directly to the central laboratory at each study site on the same day, and samples were stored at room temperature until analysis. Laboratory personnel performed the test according to the manufacturer\u0026rsquo;s instructions, interpreting results as positive if any color change occurred on the test card, indicating the presence of occult blood, or negative if no color change was observed. Internal quality control measures were implemented to ensure accuracy and consistency. The data recorded for each participant included the date of the FOBT, type of FOBT used (guaiac), and the test result (positive or negative). Guaiac-based FOBT was chosen because it is widely available, cost-effective, and suitable for screening in resource-limited settings.\u003c/p\u003e\n\u003cp\u003eColonoscopic examination\u003c/p\u003e\n\u003cp\u003eColonoscopy served as the reference standard for the detection and characterization of colorectal lesions. It was performed by trained gastroenterologists and senior gastroenterology fellows using high-resolution video colonoscopes (Fujinon) The procedure included visualization from the rectum to the cecum with photo documentation, identification and description of any lesions such as masses, polyps, ulcers, or bleeding, and biopsy or polypectomy when indicated, with samples sent for histopathological confirmation. For each colonoscopy, data collected included the date and completeness of the procedure, bowel preparation quality based on the Boston bowel preparation scale, the number, location, size, and morphology of lesions, suspected or confirmed diagnoses (e.g., adenoma, carcinoma, colitis, hemorrhoids), and histopathology results if applicable. Lesions were classified by type (polyp, colorectal cancer, diverticula, colitis, normal, or other), location (rectum, sigmoid, descending, transverse, ascending, cecum), and size in millimeters where applicable.\u003c/p\u003e\n\u003cp id=\"_Toc222660099\"\u003eOperational definitions\u003c/p\u003e\n\u003cp\u003eA \u003cstrong\u003ecolorectal neoplastic lesion:\u003c/strong\u003e was defined as rectal or colonic finding classified as advanced adenoma or non-advanced adenoma or colorectal cancer \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eNon neoplastic lesion:\u003c/strong\u003e was defined as rectal or colonic findings identified on colonoscopy that lack malignant or pre-malignant potential. These include hyperplastic polyps, Lymphoid hyperplasia, Angiodysplasia, lipomas, inflammatory polyps, diverticulosis, colitis without neoplasia and \u003cstrong\u003enon-specific mucosal changes\u003c/strong\u003e like erythema, edema, or granularity without definitive pathology(25, 26).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRisk stratification\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePatients were classified into high-risk and low-risk groups based on clinical features associated with colorectal neoplasia. Patients were categorized as high-risk if they had at least one of the following: rectal bleeding, iron-deficiency anemia, unexplained weight loss, positive family history of colorectal cancer, or previous history of colorectal polyps. Patients without any of these features were classified as low-risk. This classification was generated using variable transformation and was used for stratified analysis of FOBT diagnostic performance.\u003c/p\u003e\n\u003cp id=\"_Toc222660100\"\u003eData collection and quality assurance\u003c/p\u003e\n\u003cp\u003eData were collected using a structured digital questionnaire developed on the Kobo Collect platform. The questionnaire was developed specifically for this study based on the study objectives and relevant literature, and the English version is provided as Supplementary File 1. The tool captured sociodemographic characteristics, clinical presentation, comorbidities, FOBT results (positive/negative), colonoscopy findings, and lesion characteristics including location, size, and histological type. Eligible adult patients scheduled for colonoscopy at Tikur Anbessa Specialized Hospital and Adera Medical and Surgical Center were consecutively recruited after providing written informed consent. Sociodemographic and clinical information were obtained through face-to-face interviews using the structured questionnaire, while stool samples were collected and processed according to standard laboratory procedures. Colonoscopy was performed within four weeks of FOBT by experienced endoscopists, and suspicious lesions were biopsied for histopathological confirmation. Colonoscopic findings were cross-checked against histopathology reports to ensure the reliability of the reference standard.\u003c/p\u003e\n\u003cp\u003eTo ensure data quality, a pretest was conducted on 5% of the sample two weeks prior to the study among individuals with similar characteristics who were not included in the final analysis. Two trained general practitioners served as data collectors after receiving training on study procedures, ethical conduct, and use of the digital tool. Data were reviewed daily for completeness and consistency, and the principal investigator conducted routine supervision and random verification of records to ensure adherence to the study protocol.\u003c/p\u003e\n\u003cp id=\"_Toc222660103\"\u003eData analysis methods\u003c/p\u003e\n\u003cp\u003eData collected using the Kobo Collect tool was cleaned and exported to IBM SPSS version 27 for analysis. Descriptive statistics was performed, categorical variables were summarized using frequencies and percentages, while continuous variables were presented as mean with standard deviation if normally distributed or median with interquartile range if not. Diagnostic Performance Analysis with their95% CI (sensitivity, specificity, NPV, PPV and accuracy) was calculated using STATA statistical software version 14.2. Findings were presented using tables, graphs, and charts for clarity, with key results summarized narratively and interpreted with existing literature.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eSocio-Demographic Characteristics of the Study Participants\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA total of 240 participants were included, yielding a 100% response rate. The mean age was 43.8 \u0026plusmn; 15.1 years, with minimum of 18 year and maximum of 88 years, of these the majority (60.8%) aged 18\u0026ndash;45 years. Most participants were recruited from Adera Medical and Surgical Center 219(91.3%), with the remainder from Tikur Anbessa Specialized Hospital 21(8.8%).\u003c/p\u003e\n\u003cp\u003eThe study population showed a male predominance, with 151(62.9%) and 89(37.1%) females. Most participants resided in urban areas204 (85.0%) and were married 176(73.3%).\u003c/p\u003e\n\u003cp\u003eRegarding educational status, 104(43.3%) had college-level education or above, while 71(29.6%) completed grades 9\u0026ndash;12.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOccupationally, private-sector employees 63(26.3%) and government employees 50(20.8%) were the most common, followed by merchants 42(17.5%) and housewives 38(15.8%). The majority of participants reported a monthly income greater than 7,000 Ethiopian Birr141(58.8%), while 78(32.5%) earned 3,000\u0026ndash;7,000 Birr and 21(8.8%) earned less than 3,000 Birr.\u0026nbsp;See (Table -1) and additional sociodemographic variables are provided in Supplementary Table S1.\u003c/p\u003e\n\u003cp\u003eTable 1 Sociodemographic characteristics of study participants\u003c/p\u003e\n\u003ctable\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eVariables\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eCategory\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eFrequency\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003ePercent (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eHospital\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eAdera Medical and Surgical center\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e219\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e91.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eTikur Anbessa Specialized Hospital (TASH)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eSex\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e37.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e151\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e62.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eAge category\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e18-45 years old\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e146\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e60.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026gt;45 years old\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e39.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\"\u003e\n \u003cp\u003eMean age\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e43.84\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003ePlace of residence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eRural\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e15.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eUrban\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e204\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e85.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\"\u003e\n \u003cp\u003eMarital status\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eDivorced\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMarried\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e176\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e73.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSingle\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e18.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eWidowed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e-[[]\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical and Laboratory Characteristics of the Study Participants\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe majority of participants were symptomatic at presentation (87.9%), with abdominal pain (84.2%) and change in bowel habit (67.9%) being the most frequently reported symptoms. Only 12.1% underwent colonoscopy for asymptomatic colorectal cancer screening.\u003c/p\u003e\n\u003cp\u003eOverall, 30.4% of participants had a positive FOBT, while 69.6% tested negative (Fig-1). Recent overt gastrointestinal bleeding was reported by a minority (14.2%), and iron deficiency anemia was uncommon (6.7%). Weight loss was reported in approximately one-quarter of participants (26.7%).\u003c/p\u003e\n\u003cp\u003eA family history of colorectal cancer and prior colonic polyps were rare, reported in 1.7% and 5.0% of participants, respectively. Based on predefined clinical risk stratification, 135 (56.3%) patients were classified as low-risk and 105 (43.8%) as high-risk\u003c/p\u003e\n\u003cp\u003eCommon comorbidities included hypertension (17.9%), diabetes mellitus (10.0%), and liver disease (11.3%), while cardiovascular and cerebrovascular diseases were infrequent.\u003c/p\u003e\n\u003cp\u003eLifestyle risk factors were uncommon, with very low prevalence of smoking and alcohol consumption. All participants underwent guaiac-based FOBT, most commonly performed once prior to colonoscopy (85.8%). Mean laboratory values were within normal ranges, including hemoglobin (14.67 g/dL), mean corpuscular volume (85.98 fL), and platelet count (242.57 \u0026times;10⁹/L). See (Table -2) and additional detail clinical characteristics variables provided in \u003cstrong\u003eSupplementary Table S2\u003c/strong\u003e\u003c/p\u003e\n\u003cp id=\"_Toc222173163\"\u003eTable\u0026nbsp;2 Clinical characteristics of study participants\u003c/p\u003e\n\u003ctable\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eVariables\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eCategory\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eFrequency\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003ePercent (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eColorectal cancer screening without any symptom\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e211\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e87.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e12.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eBlood in the stool ,2weeks prior to FOBT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e206\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e85.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e14.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eWeight loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e176\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e73.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e26.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003e\u0026nbsp;Abdominal pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e15.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e202\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e84.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eBowel habit (diarrhea or constipation)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e32.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e163\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e67.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eIron deficiency anemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e224\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e93.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\"\u003e\n \u003cp\u003eFamily history of colorectal cancer\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e235\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e97.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eUnknown\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eHistory of colonic polyp\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e228\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e95.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eRisk stratification\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eLow risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e135\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e56.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eHigh risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e105\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e43.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eColonoscopic finding distribution among study participants\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMost colonoscopies were performed for diagnostic indications 222(92.5%), while screening colonoscopies accounted for 18(7.5%). Bowel preparation quality was rated as excellent in 169(70.4%), good in 60(25.0%), and poor in 11(4.6%). Cecal intubation was achieved in 205(85.4%) procedures. Abnormal colonoscopic findings were identified in 141(58.8%) patients, whereas 99(41.3%) had normal examinations. Among abnormal findings, other morphological lesions were most frequent 60(42.6%), followed by inflammatory lesions 39(27.7%), polyps 30(21.3%), mass-forming lesions 8(5.7%), and ulcerated lesions 4(2.8%). Within the \u0026ldquo;other\u0026rdquo; category, hemorrhoids were predominant 43(71.7%). Most polyps were non-pedunculated 28(93.3%), while pedunculated polyps were uncommon 2(6.7%). Colonoscopic findings suspicious for colorectal cancer were observed in 9(6.4%) patients. Lesions were most commonly located in the rectum 65(46.1%), followed by the ascending colon 23(16.3%), sigmoid colon 17(12.1%), and ileum 15(10.6%). Distal lesions 82(58.2%) were more frequent than proximal lesions 59(41.8%). Lesions measuring \u0026ge;10 mm were identified in 16(11.3%), while 18(12.8%) measured \u0026lt;10 mm. See table-3 and detail of colonoscopic finding provided in \u003cstrong\u003eSupplementary Table S3\u003c/strong\u003e\u003c/p\u003e\n\u003cp id=\"_Toc222173164\"\u003eTable\u0026nbsp;3 Distribution of colonoscopic findings among study participants\u003c/p\u003e\n\u003ctable\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eVariables\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eCategory\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eFrequency\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003ePercent (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"5\"\u003e\n \u003cp\u003eColonoscopy findings morphology\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eInflammatory\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e27.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMass forming lesion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eOthers Specify\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e42.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePolyp\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e21.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eUlcerated lesion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"6\"\u003e\n \u003cp\u003eOther specified colonoscopic findings\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eAphthous ulcer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eDiverticulosis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eHemorrhoids\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e71.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eparasitic infection\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSpastic colon\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e15.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eVolvulus\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eClassification of lesion based on location\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eDistal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e58.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eProximal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e41.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHistopathologic findings among biopsied patients\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHistopathologic results were analysed using biopsied patients as the denominator to ensure accurate estimation of tissue confirmed diagnoses. Among the biopsied patients (n = 80), non-specific colitis was the predominant histopathologic finding 41 (51.2%), followed by lymphoid hyperplasia 11 (13.8%). Colorectal adenocarcinoma was identified in 5 (6.3%) patients. (Table -4)\u003c/p\u003e\n\u003cp id=\"_Toc222173165\"\u003eTable\u0026nbsp;4 Histopathologic findings among biopsied lesions\u003c/p\u003e\n\u003ctable style=\"width: 3.7e+2pt;\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eFrequency\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003ePercent (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003e\u0026nbsp;Biopsy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e160\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e66.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e33.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"7\"\u003e\n \u003cp\u003eHistopathologic diagnosis\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eColorectal adenocarcinoma\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eHyperplastic polyp\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e7.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eLymphoid hyperplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e13.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNon-specific colitis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e51.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNormal colonic histology\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eOthers (specify)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e10.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eTubular adenoma\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e7.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\"\u003e\n \u003cp\u003eOther specified histopathology diagnosis\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003echronic active proctitis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e12.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eGlandular intraepithelial neoplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e12.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003einflammatory polyp\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e62.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eUndifferentiated malignant tumor\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e12.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eComparison of Colonoscopic and Histopathologic Findings by Fecal Occult Blood Test (FOBT) Result\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAmong patients with abnormal colonoscopic findings, morphological patterns differed by FOBT result. In the FOBT-negative group, the most common findings were other lesions 44(45.4%), followed by inflammatory lesions 25(25.8%) and polyps 23(23.7%), while mass-forming lesions 3(3.1%) and ulcerated lesions 2(2.1%) were less frequent. In the FOBT-positive group, other lesions 16(36.4%) and inflammatory lesions 14(31.8%) predominated, with a higher proportion of mass-forming lesions 5(11.4%) compared to the FOBT-negative group.\u003c/p\u003e\n\u003cp\u003eFindings suspicious for colorectal cancer were uncommon in FOBT-negative patients 2(2.1%), but were more frequent among FOBT-positive patients 7(15.9%). Distal lesions were more common in FOBT-negative patients 60(61.9%), whereas lesion distribution was equal between distal and proximal locations in FOBT-positive patients 22(50.0%) each.\u003c/p\u003e\n\u003cp\u003eBiopsy was performed in 54(32.3%) FOBT-negative and 26(35.6%) FOBT-positive patients. The most frequent histopathologic diagnosis in both groups was non-specific colitis 28(51.9%) vs 13(50.0%), followed by lymphoid hyperplasia and hyperplastic polyps. Colorectal adenocarcinoma was identified more commonly in FOBT-positive patients 3(11.5%) than in FOBT-negative patients 2(3.7%). Fig-2\u003c/p\u003e\n\u003cp\u003eLow-grade dysplasia was observed in 3(5.6%) FOBT-negative and 3(11.5%) FOBT-positive patients, while high-grade dysplasia was rare 1(1.9%), occurring only in the FOBT-negative group. Overall, non-neoplastic lesions constituted the majority of final diagnoses in both FOBT-negative 160(95.8%) and FOBT-positive 67(91.8%) patients, whereas advanced neoplasia was more frequent in the FOBT-positive group 4(5.5%) compared to the FOBT-negative group 3(1.8%). See \u0026nbsp;detail of FOBT result distribution among colonoscopic and histologic finding provided in \u003cstrong\u003eSupplementary Table S4\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDiagnostic Accuracy of the Fecal Occult Blood Test\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOverall, FOBT demonstrated limited diagnostic performance for general colorectal abnormalities and polyps, but moderate utility for neoplastic lesions, particularly advanced neoplasia and adenocarcinoma. For altered colonoscopic findings (prevalence 58.8%), FOBT showed low sensitivity (31.2%) with moderate specificity (70.7%), indicating poor ability to detect non-specific mucosal abnormalities. Similarly, diagnostic yield for polyps was low (overall sensitivity 23.3%), irrespective of lesion location. When stratified by clinical risk category, FOBT showed similarly low sensitivity for altered colonoscopic findings in both low-risk (32.9%) and high-risk patients (29.2%), with moderate specificity in both groups. This suggests limited utility of FOBT for detecting non-neoplastic abnormalities regardless of baseline clinical risk.\u003c/p\u003e\n\u003cp\u003eIn contrast, FOBT demonstrated better performance for neoplastic lesions. For any colorectal neoplasia (overall prevalence 5.4%), sensitivity was 46.2% with a high negative predictive value (95.8%), supporting its role as a rule-out test. Diagnostic performance was superior for distal neoplasia compared with proximal lesions (sensitivity 75% vs 33.3%). Importantly, all neoplastic lesions, including advanced neoplasia and adenocarcinoma, were observed exclusively in the high-risk group. As a result, diagnostic accuracy parameters for neoplastic outcomes could not be calculated for low-risk patients. Among high-risk patients, FOBT demonstrated moderate sensitivity for any neoplasia (60%) and advanced neoplasia (57.1%), with consistently high NPVs (\u0026gt;94%). Detection of adenocarcinoma in the high-risk group showed a sensitivity of 60% and an NPV of 97.3%.\u003c/p\u003e\n\u003cp\u003ePositive predictive values remained low across all outcomes, underscoring the need for confirmatory colonoscopy following a positive FOBT. Overall, FOBT has limited value for detecting polyps and non-neoplastic abnormalities, but demonstrates moderate diagnostic accuracy for clinically significant neoplasia, particularly in high-risk patients, supporting its use as a triage and exclusion tool rather than a definitive diagnostic test. See Table- 6 and Detailed subgroup analysis of diagnostic performance test are provided in \u003cstrong\u003eSupplementary Table S5\u003c/strong\u003e.\u003c/p\u003e\n\u003cp id=\"_Toc222173167\"\u003eTable 5 FOBT diagnostic performance for colorectal neoplasia in Addis Ababa, Ethiopia\u003c/p\u003e\n\u003ctable style=\"width: 119%;\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eLesion\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eLesion location\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003ePrevalence (%) u\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eSensitivity\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpecificity\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003ePPV\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eNPV\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eAccuracy\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e95%CI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e95%CI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e95% CI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e95%CI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e95% CI\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAltered colonoscopic finding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e58.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e31.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e23.7-39.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e70.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e60.7 \u0026nbsp; -79.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e60.3\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e48.1 - 71.5\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e41.9\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e34.3-49.8\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e47.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1.04 -54.02\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAny Neoplastic lesion\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e46.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e19.2 - 74.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e70.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e64.1 - 76.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.1 - 17.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e95.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e91.6 - 98.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e69.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e62.90 -74.95\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAny polyp\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e12.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e23.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9.9 - 42.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e68.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e61.8 - 74.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.9 - 18.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e86.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e80.1 - 91.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e62.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e56.47- 69.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAdvanced neoplasia\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e57.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e18.4 - 90.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e70.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e64.1 - 76.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1.5 - 13.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e98.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e94.8 - 99.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e63.77 - 75.73\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eNon advanced neoplasia\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e33.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.3 - 77.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e69.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e63.3 -75.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.3 - 9.5\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e97.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e94.0 - 99.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e68.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e62.47 -74.56\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eTubular adenoma\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e33.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.3 - 77.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e69.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e63.3 -75.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.3 - 9.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e97.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e94.0 - 99.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e68.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e62.47-74.56\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAdenocarcinoma\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e60 \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e14.7 - 94.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e70.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e63.9 - 76.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.9 - 11.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e98.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e95.7- 99.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e63.77 -75.73\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis hospital-based cross-sectional study evaluated the diagnostic performance of the guaiac-based fecal occult blood test (FOBT) in detecting colorectal neoplastic lesions. The findings provide important insights into the utility and limitations of FOBT in the Ethiopian clinical context, where colonoscopy access remains limited.\u003c/p\u003e\n\u003cp\u003eThe study population had a mean age of 43.8 years, younger than typical colorectal screening cohorts in high-income countries, where average screening age is above 50 years. This reflects the diagnostic nature of colonoscopy use in Ethiopia, where patients present earlier due to symptoms rather than structured screening programs(27). Similarly, limited evidence from sub-Saharan Africa indicates that colorectal cancer often presents in younger age groups and at more advanced stages compared with high-income countries. Given the region\u0026rsquo;s shorter life expectancy (approximately 50\u0026ndash;60 years), the conventional screening age of 50 years used in Western countries may not be realistic. Additionally, most countries in this region lack nationwide CRC screening protocols, which likely contributes to delayed diagnosis and younger symptomatic presentation(28-30). In our cohort men comprised 59.2% of participants. This male predominance is consistent with findings from a large outreach colonoscopy series in Southwest Ethiopia, which reported a predominantly male cohort (70.6%) with a mean age of 44 years and the majority under 50. The similar male skew in these Ethiopian series may reflect local referral patterns, symptomatic presentation among working-age men, or differential access to endoscopy services rather than true population prevalence of colorectal disease(31).\u003c/p\u003e\n\u003cp\u003eIn our two-center study, the overall cecal intubation rate (CIR) was 84.5%. International quality benchmarks recommend a cecal intubation rate of \u0026ge;90% for all colonoscopies and \u0026ge;95% for screening colonoscopies. Compared with these standards, the CIR in our study is lower than the recommended targets.(32, 33). However, when interpreted in the context of real-world practice, our findings are comparable to several observational studies, particularly those conducted outside high-volume tertiary academic centers. Studies from routine clinical practice, especially in mixed-indication colonoscopy populations, have reported CIRs ranging from 77% to 89%, which overlaps with our result. Lower completion rates in such settings have been attributed to factors including variable bowel preparation quality, patient comorbidities, complex colonic anatomy, and limited procedural support(34-36).\u003c/p\u003e\n\u003cp\u003eAbnormal colonoscopic findings were common in both FOBT-positive and negative groups (\u0026asymp;59% overall). Inflammatory conditions and hemorrhoids were the most frequent abnormality, consistent with prior Ethiopian studies showing a high burden of non-neoplastic gastrointestinal diseases(31, 37). Polyps accounted for approximately 20% of lesions, while mass-forming lesions and colonoscopic suspicion of malignancy were noticeably more frequent among FOBT-positive participants, reflecting the biological link between bleeding and advanced lesions. Lesion distribution showed a predominance of distal involvement, particularly rectal lesions, which represented nearly half of abnormal findings. This pattern is consistent with African and Asian studies reporting a distal shift in colorectal lesions compared with Western populations(38).\u003c/p\u003e\n\u003cp\u003eHistology confirmed that most biopsied lesions were non-neoplastic, with non-specific colitis being the dominant finding. Adenocarcinoma prevalence (2.1%) was low but higher among FOBT-positive participants. Advanced neoplasia was also more frequent in the FOBT-positive group (5.5% vs. 1.8%), supporting the potential rule-in value of FOBT for significant pathology. This finding with consistent with recent study from south west Ethiopia however prevalence of adenocarcinoma in our study is lower which is likely from lower sample size (31).\u003c/p\u003e\n\u003cp\u003eIn the present study, FOBT demonstrated moderate sensitivity (46.2%) and specificity (70.5%) for the detection of any colorectal neoplasia, with an excellent negative predictive value (NPV) of 95.8%. This finding indicates that a negative FOBT result is useful for ruling out colorectal neoplasia, particularly in populations with a low prevalence of disease. Similar high NPVs have been reported in prior studies, ranging from 95.4% for guaiac-based FOBT and 97.5% for fecal immunochemical testing (FIT) in screening populations, and increasing to 98.99% and 99.56%, respectively, in hospital-based settings (39, 40). The sensitivity of gFOBT observed in this study is comparable to values reported in meta-analyses, where sensitivity for neoplasia detection varies widely from as low as 6% to approximately 46% in cohort-based settings (41). However, the specificity observed in this study (approximately 70%) is lower than that reported in many population-based screening studies, which often demonstrate specificities exceeding 80%(42). These discrepancies may be attributable to differences in study design, patient selection, testing protocols, and sample size, all of which can substantially influence diagnostic accuracy estimates.\u003c/p\u003e\n\u003cp\u003eFOBT performance varied according to lesion location. Sensitivity for distal neoplastic lesions reached 75%, whereas sensitivity for proximal lesions was markedly lower (33.3%). This pattern is consistent with established evidence that FOBT preferentially detects bleeding from left-sided lesions due to shorter intestinal transit time and reduced hemoglobin degradation. Meta-analyses have similarly demonstrated higher sensitivity for distal compared with proximal colorectal cancer, with pooled estimates of approximately 80.1% versus 71.2%, respectively(43).\u0026nbsp;Comparable trends have been reported for FIT, with significantly higher pooled sensitivities for distal advanced neoplasia compared to proximal disease (40).\u003c/p\u003e\n\u003cp\u003eNotably, gFOBT demonstrated higher sensitivity for clinically significant lesions in this cohort, with sensitivities of 57.1% (95% CI: 18.4\u0026ndash;90.1) for advanced neoplasia and 60% (95% CI: 14.7\u0026ndash;94.7) for colorectal adenocarcinoma, along with very high NPVs (\u0026gt;98%) for both outcomes. These values exceed those typically reported in average-risk screening populations, where sensitivity for advanced neoplasia generally ranges from the low tens to low 30% and sensitivity for colorectal cancer ranges from approximately 25% to 38% when colonoscopy is used as the reference standard(41, 44). The relatively higher sensitivities observed in this study likely reflect the symptomatic nature of the study population and the higher pre-test probability of clinically significant disease.\u003c/p\u003e\n\u003cp\u003eImportantly, patients in this study were further stratified into high-risk and low-risk groups based on predefined clinical criteria, including rectal bleeding, iron deficiency anemia, unexplained weight loss, family history of colorectal cancer, and prior history of colorectal polyps. All detected neoplastic lesions occurred within the high-risk group, resulting in zero neoplasia events among low-risk patients. Consequently, diagnostic performance metrics such as sensitivity and positive predictive value could not be calculated for the low-risk subgroup due to the absence of outcome events. This finding is not a methodological limitation but rather reflects the strong discriminative value of clinical risk stratification in this cohort.\u003c/p\u003e\n\u003cp\u003eThese results underscore that FOBT should not be used to exclude colonoscopy in high-risk symptomatic patients, even when FOBT results are negative. In contrast, among low-risk patients without alarm features, the absence of neoplasia combined with the high NPV of FOBT supports its potential role as a triage tool to safely defer or prioritize colonoscopy in resource-limited settings. This approach aligns with international recommendations, which consistently emphasize that alarm features and high-risk clinical characteristics should prompt colonoscopic evaluation regardless of stool test results(45). However, in our study gFOBT done one times in majority of patients as result it may be appropriate to repeat FOBT before deferring colonoscopy even in low-risk patients.\u003c/p\u003e\n\u003cp\u003eDespite the relatively higher sensitivities observed in this study, large comparative analyses consistently demonstrate that fecal immunochemical tests outperform guaiac-based FOBT, with reported sensitivities of approximately 33% versus 15% for advanced neoplasia and 76% versus 39% for colorectal cancer, respectively(41). Therefore, while gFOBT may have utility as a triage and exclusion tool in selected settings, FIT remains the preferred non-invasive stool-based test where available.\u003c/p\u003e\n\u003cp\u003eTaken together, the findings of this study suggest that gFOBT has limited utility for detecting non-neoplastic and polypoid lesions but demonstrates moderate diagnostic accuracy for clinically significant neoplasia, particularly advanced lesions. When combined with careful clinical risk stratification, FOBT may serve as a pragmatic triage tool in symptomatic patients, especially in resource-constrained environments. However, colonoscopy remains mandatory for high-risk patients irrespective of FOBT results.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eStrengths and limitations of the Study\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThis study has several key strengths. Its prospective design with standardized assessments minimized bias and allowed accurate comparison between FOBT and colonoscopy findings. The use of colonoscopy with histopathology as the reference standard ensured reliable classification of colorectal lesions, while consecutive sampling in tertiary hospitals enhanced real-world applicability in a resource-limited setting. Furthermore, detailed lesion characterization and clinical risk stratification enabled meaningful subgroup analyses, improving the clinical relevance of the findings. Despite these strengths, several limitations should be noted. The study was conducted among symptomatic patients in tertiary centers, limiting generalizability to population-based screening. Use of a single guaiac-based FOBT may have underestimated diagnostic performance compared with repeated testing or fecal immunochemical testing. The small number of neoplastic cases in some subgroups reduced the precision of estimates, and the absence of neoplasia in low-risk patients prevented calculation of some diagnostic metrics. Finally, as the study was conducted in a resource-limited tertiary setting, findings may not fully apply to primary care or higher-resource healthcare environments.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eFOBT demonstrated limited sensitivity for non-neoplastic lesions and polyps but moderate diagnostic accuracy for clinically significant colorectal neoplasia, particularly advanced neoplasia and adenocarcinoma, with high negative predictive value. All neoplastic lesions were identified in high-risk symptomatic patients, underscoring the critical role of clinical risk stratification. Accordingly, colonoscopy remains mandatory for high-risk patients regardless of FOBT results. In contrast, among low-risk symptomatic patients without alarm features, FOBT may serve as a pragmatic triage tool to prioritize colonoscopy in resource-limited settings.\u003c/p\u003e\n\u003cp\u003eStrengthening clinician adherence to risk stratification, implementing structured referral and follow-up systems, and integrating risk-stratified FOBT use into national colorectal cancer strategies are recommended to optimize resource allocation. Where feasible, fecal immunochemical testing (FIT) should be adopted given its superior sensitivity. Future research should evaluate FIT-based strategies in population settings, assess cost-effectiveness of stool-based triage versus direct colonoscopy referral, and refine combined clinical and stool-based risk models to improve early detection while conserving limited endoscopy capacity.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eCIR: \u0026nbsp;Cecal Intubation Rate\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCRC \u0026nbsp; \u0026nbsp; \u0026nbsp; Colorectal Cancer\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFOBT \u0026nbsp; \u0026nbsp; Fecal Occult Blood Test\u003c/p\u003e\n\u003cp\u003egFOBT \u0026nbsp; \u0026nbsp; Guaiac-based Faecal Occult Blood Test\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFIT \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Faecal \u003cem\u003eI\u003c/em\u003emmunochemical Test\u003c/p\u003e\n\u003cp\u003eMCV \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Mean Corpuscular Volume\u003c/p\u003e\n\u003cp\u003eNPV \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Negative Predictive Value\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNSAID \u0026nbsp; \u0026nbsp; \u0026nbsp;Non-steroidal Anti-inflammatory Drugs\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePLT \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Platelet\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePPV \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Positive Predictive Value\u003c/p\u003e\n\u003cp\u003eTASH \u0026nbsp; \u0026nbsp; Tikur Anbessa Specialized Hospital\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval was obtained from the \u003cstrong\u003eInstitutional Review Board (IRB) of Addis Ababa University, College of Health Sciences\u003c/strong\u003e, Internal Medicine Department review board with protocol number 14/25 and Meeting number 07/25 on 23/05/2025. The study was conducted in accordance with the ethical principles of the declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAuthors states that they did not receive any fund for the study nor for the publication.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMK conceived and designed the study, performed data collection, conducted the statistical analysis, and drafted the manuscript. AB critically reviewed the manuscript for important intellectual content. GM contributed to the study methodology and provided methodological oversight\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe would like to express our sincere gratitude to Addis Ababa University, College of Health Sciences, for allowing us to conduct this study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eSung H, Ferlay J, Siegel RL, Laversanne M, Soerjomataram I, Jemal A, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin. 2021;71(3):209-49. doi: {10.3322/caac.21660}\u003c/li\u003e\n\u003cli\u003eBray F, Laversanne M, Sung H, Ferlay J, Siegel RL, Soerjomataram I, et al. Global cancer statistics 2022: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. 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Gastroenterology. 2017;153(1):307-23. doi:\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Colonoscopy, fecal occult blood test, diagnostic accuracy test, colorectal cancer, colonic polyps","lastPublishedDoi":"10.21203/rs.3.rs-9313580/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9313580/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Colorectal cancer (CRC) is a major health concern, and early detection reduces its burden. The fecal occult blood test (FOBT) is a non-invasive, cost-effective screening tool, but its accuracy varies by test type and tumor location. Colonoscopy is the gold standard but limited in resource-constrained settings like Ethiopia. This study evaluated the diagnostic performance of FOBT in detecting colorectal neoplastic lesions among patients undergoing colonoscopy in Addis Ababa, Ethiopia.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethod\u003c/strong\u003e: An institution-based, prospective cross-sectional study was conducted from August 1 to October 30, 2025, among 240 patients using consecutive sampling. Data on demographics, clinical factors, FOBT results, and colonoscopy findings were collected via structured interviews and Kobo Collect. Diagnostic accuracy of FOBT was assessed using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy with 95% confidence intervals. Analyses were performed using IBM SPSS version 27 and STATA version 14.2.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Of 240 participants, 30.4% had a positive guaiac-based FOBT (gFOBT). For any colorectal neoplastic lesion, gFOBT showed moderate sensitivity (46.2%) and specificity (70.5%), with a high NPV (95.8%), indicating strong ability to rule out significant neoplasia. Sensitivity was higher for distal lesions (75%) than proximal lesions (33.3%). For colorectal adenocarcinoma, gFOBT sensitivity was 60% with a very high NPV (98.8%). All neoplastic lesions occurred in high-risk patients, yielding consistently high NPVs (\u0026gt;97%), while PPVs remained low.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e In this Ethiopian tertiary-care setting, guaiac-based FOBT demonstrated limited sensitivity but moderate specificity and consistently high NPV for clinically significant colorectal neoplasia, especially adenocarcinoma. While insufficient as a standalone diagnostic test, gFOBT can serve as a triage and exclusion tool in low-risk patients, helping prioritize colonoscopy in resource-limited settings, whereas high-risk patients should undergo colonoscopy regardless of FOBT results.\u003c/p\u003e","manuscriptTitle":"Diagnostic Accuracy of Fecal Occult Blood Testing for Colorectal Neoplasia in a Tertiary Care Setting: A Prospective Study from Ethiopia","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-11 10:06:45","doi":"10.21203/rs.3.rs-9313580/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-05-15T17:49:51+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-09T12:13:07+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"242416446297696329435048554918753556448","date":"2026-05-07T10:00:00+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"160091121844603239165056434904074253538","date":"2026-05-07T08:40:40+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-30T11:02:08+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-26T20:21:30+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-04-09T07:34:44+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-08T16:09:45+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Gastroenterology","date":"2026-04-08T15:41:54+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"2d849976-8968-4469-bb28-288ea55d94af","owner":[],"postedDate":"May 11th, 2026","published":true,"recentEditorialEvents":[{"type":"editorInvitedReview","content":"","date":"2026-05-15T17:49:51+00:00","index":64,"fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-09T12:13:07+00:00","index":63,"fulltext":""},{"type":"reviewerAgreed","content":"242416446297696329435048554918753556448","date":"2026-05-07T10:00:00+00:00","index":58,"fulltext":""},{"type":"reviewerAgreed","content":"160091121844603239165056434904074253538","date":"2026-05-07T08:40:40+00:00","index":57,"fulltext":""},{"type":"reviewersInvited","content":"30","date":"2026-04-30T11:02:08+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-11T10:06:45+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-11 10:06:45","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9313580","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9313580","identity":"rs-9313580","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}