Establishing a Caseness Cutoff and Reliable Change Index for the Outcome Measurement Scale

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However, its implementation in real-world practice—particularly in non-Western settings—remains limited, partly due to a lack of brief and interpretable outcome measures. The Outcome Measurement Scale (OMS) was developed to address this gap by assessing both psychological distress and multidimensional well-being in South Korea. This study aimed to establish two key interpretive anchors for the OMS: a caseness cutoff score and a Reliable Change Index (RCI) to support its clinical and public health applications. Methods: A sample of 1,400 adults from South Korea completed both the OMS and the WHO-5 Well-Being Index, a validated measure of subjective well-being. Equipercentile linking and Receiver Operating Characteristic (ROC) analysis were employed to identify the OMS score corresponding to the WHO-5 caseness threshold (< 13). The RCI was calculated using the Jacobson–Truax method based on estimated measurement error and internal consistency reliability. Results: Equipercentile linking indicated that a WHO-5 score of 13 corresponded to an OMS score of 33, while ROC analysis identified 31 as the optimal cutoff (AUC = 0.90; sensitivity = 0.88; specificity = 0.27). The OMS and WHO-5 demonstrated strong correlation ( r = 0.80). The RCI was calculated as 8.11 points for the full sample and 6.77 points for the clinical subsample, suggesting that a change of approximately 7–8 points reflects statistically reliable improvement or deterioration at the 95% confidence level. Conclusion: An OMS score of approximately 31 serves as a practical caseness threshold, while a 7–8 point change represents reliable individual change. These interpretive benchmarks enable clinicians and public health professionals to screen for low well-being, track meaningful change, and evaluate service outcomes using the OMS. The findings highlight the OMS as a brief and useful tool for ROM implementation in both clinical and community mental health settings. Routine outcome monitoring Outcome Measurement Scale reliable change index caseness cutoff linking Figures Figure 1 Introduction Over the past several years, particularly in the wake of the COVID-19 pandemic, public concern about mental health has grown substantially. In tandem, there have been increased demands for psychotherapy and counseling services to demonstrate effectiveness in a systematic and evidence-based manner. As an evidence-based practice, Routine Outcome Monitoring (ROM) has emerged as a widely endorsed strategy [25, 9]. ROM, also referred to as measurement-based care or feedback-informed treatment, generally involves three components: (1) collecting data from clients at regular intervals, (2) providing feedback based on the data to the therapist and, in many cases, to the client as well, and (3) using this feedback to adjust therapy when clinically appropriate. Numerous studies have shown that ROM can enhance treatment responsiveness, reduce client deterioration, and improve outcomes overall [26]. ROM is a cost-effective method that can enhance therapy outcomes with minimal additional cost [11]. Despite its proven utility, ROM remains underutilized in many real-world mental health settings—for example, only 14% of clinicians reported using ROM in routine practice in a national U.S. survey [20]—particularly in non-Western contexts such as South Korea [21]. One limiting factor has been the lack of brief and psychometrically sound outcome measures that are feasible for routine clinical use. In response to this gap, the Outcome Measurement Scale (OMS) was recently developed to support ROM in Korean clinical settings [31]. The OMS is designed to assess both multidimensional well-being and psychological distress, thus capturing both symptom reduction and well-being in a concise and clinically practical five-item format. Unlike symptom-focused measures such as the PHQ-9, which may not adequately capture clients’ perceptions of recovery (e.g., confidence, interpersonal harmony [8]), the OMS provides a more holistic view by assessing various domains of well-being—thereby offering greater insight into clients’ psychological recovery and personal growth. The OMS has demonstrated psychometric validity in a validation study conducted with a general adult sample of 1,400 participants across a wide age range. The scale showed strong evidence of construct validity and excellent internal consistency (Cronbach’s α = 0.93). To support meaningful interpretation and clinical decision-making within ROM systems, the OMS requires two key interpretive anchors: a caseness cutoff score and a Reliable Change Index (RCI). The caseness cutoff represents a threshold below which a client is considered to be at potential clinical risk and may benefit from therapeutic intervention. Establishing such a cutoff enables clinicians to identify individuals in need of care and to benchmark symptom improvement or recovery over time. In parallel, the RCI provides a statistical index for determining whether the change in a client’s OMS score across time—such as from pre- to post-treatment—is greater than what could be attributed to measurement error alone [19, 5]. The RCI allows therapists to distinguish between reliable improvement, deterioration, and no meaningful change, thereby enhancing the precision of outcome feedback. In this study, we aimed to establish both the caseness cutoff score and the RCI for the OMS to enable its valid and practical use in ROM. In this study, the WHO-5 Well-Being Index was used as the primary reference instrument to derive the OMS cutoff. The WHO-5, developed by the World Health Organization, is a five-item, positively framed scale that measures subjective well-being, including emotional vitality, restfulness, and satisfaction with life [30]. It has been translated into over 30 languages and has been widely validated as both a general mental health indicator and a depression screener. A score of < 13 on the WHO-5 is commonly used to indicate low well-being or probable depressive caseness [28]. Conceptually, the WHO-5 and OMS share overlap: both focus on functional and positive emotional aspects of well-being, rather than solely on clinical symptoms. The OMS includes dimensions of well-being related to psychological distress, self-concept, intimate relationships, work and role, and overall life satisfaction. This conceptual alignment was further supported by a strong empirical correlation in the present sample ( r = 0.81), indicating substantial shared variance and convergent validity. To derive an empirically supported OMS cutoff, two complementary analytic methods were employed: equipercentile linking and Receiver Operating Characteristic (ROC) analysis. Equipercentile linking was used to determine the OMS score that corresponds to the same distributional position as a WHO-5 score of 13, thus providing a norm-referenced equivalence. ROC analysis, in contrast, was used to evaluate the diagnostic accuracy of the OMS score in predicting WHO-5 caseness status, estimating optimal sensitivity and specificity. Each method has unique advantages: equipercentile linking offers interpretability and normative consistency, while ROC analysis provides statistical rigor and classification accuracy. By combining both, the study aimed to derive a cutoff that is both practically meaningful and psychometrically robust. To calculate the OMS RCI, we applied the Jacobson–Truax method [19]. To enhance applicability across diverse settings, we derived two RCI values: one based on the general adult population and another based on the subsample within the clinical range. For counselors, the RCI derived from the clinical sample is particularly useful for tracking client progress during therapy. In contrast, the RCI based on the general population enables the scale to be applied in non-clinical, community-based contexts (e.g., schools, workplace wellness programs, and public health screenings). This dual approach supports the use of a single tool for both prevention and treatment purposes, thereby increasing its utility across a wide range of mental health service environments. Study purpose The primary aim of this study is to enhance the clinical utility of the OMS within ROM systems by establishing two key interpretive anchors. Specifically, this study seeks to establish a caseness cutoff score for the OMS using equipercentile linking and ROC analysis based on the WHO-5 Well-Being Index, and to calculate the RCI for the OMS with the full study sample and its subsample who scored below the caseness point of the OMS. Methods Study Design and Sample This study employed a single-group linking design in which all participants completed the OMS and WHO-5 measures. Single-group designs are considered robust for scale linking because the same individuals take both instruments, allowing direct score comparisons and strengthening the validity of the linking relationship. The sample consisted of 1,400 adults (50.7% male, 49.3% female) in South Korea, aged 20 to 69 years, recruited through a survey panel. The data were originally collected as part of the OMS validation study. Participants had a mean age of 39 years (SD = 15.3). By age group, 566 (40.4%) were in their 20s, 175 (12.5%) in their 30s, 213 (15.2%) in their 40s, 240 (17.1%) in their 50s, and 206 (14.7%) in their 60s. All participants provided informed consent prior to participation, and the study was approved by an institutional ethics review board. Measures Outcome Measurement Scale (OMS). The OMS is a recently developed brief outcome instrument consisting of 5 items that assess psychological distress and multidimensional well-being (covering self-concept, close relationships, work/role functioning, and overall life satisfaction). Each item is rated on an 11-point Likert scale from 0 (“very poor”) to 10 (“very good”), with higher scores indicating better well-being and less distress. Total scores range from 0 to 50. In the original validation, the OMS demonstrated excellent internal consistency (Cronbach’s α = 0.93) and strong criterion validity, correlating highly (inversely) with established measures of distress (e.g., r = − 0.78 with the Korean Inventory of Clinical Outcomes in Routine Evaluation-Outcome Measure). WHO-5 Well-Being Index. The World Health Organization’s Five Well-Being Index (WHO-5) is a 5-item measure of subjective well-being. Each item is rated on a 6-point scale from 0 (“at no time”) to 5 (“all of the time”), assessing positive mood (e.g., “I felt cheerful and in good spirits”) and vitality over the past two weeks. Total scores range from 0 to 25, with higher scores reflecting better well-being. The WHO-5 has been widely validated as a screening tool for depression; a score < 13 is conventionally used to indicate low well-being or probable depressive caseness. In this study, we used the Korean version of the WHO-5 [20], which has shown high internal consistency in prior research ( α = 0.83–0.91) and was α = 0.94 in our sample (Table 1 ). Table 1 Descriptive Statistics and Reliability Test nan N Mean SD Skew Kurt Cronbach \(\:{\alpha\:}\) OMS Total 1,400 30.80 10.35 -0.37 2.73 0.93 Male 710 31.16 10.35 -0.47 2.86 Female 690 30.43 10.33 -0.26 2.62 WHO-5 Total 1,400 12.01 6.08 0.00 2.14 0.94 Male 710 12.30 6.19 -0.03 2.08 Female 690 11.71 5.94 0.02 2.20 Note: OMS = Outcome Measurement Scale; WHO-5 = WHO-Five Well-Being Index. Cronbach’s α values are presented for total scores. Analytical Procedures Equipercentile linking. To establish a caseness cutoff on the OMS, we first conducted equipercentile linking with the WHO-5 as the reference instrument. Equipercentile linking aligns scores on two scales such that the linked scores have the same cumulative percentile rank in their respective distributions[3]. This approach produces a nonlinear score transformation (cross-walk) that equates each WHO-5 score with an OMS score having an equivalent percentile rank in the sample. Given that all participants completed both instruments, a single-group design was used. This design is ideal when the two tests measure similar constructs and have a high correlation (typically r ≥ 0.75–0.80 ). We also assessed group invariance of the linking relationship across gender by computing the standardized Root Expected Mean Square Difference (REMSD) for males vs. females. We generated the OMS and WHO-5 cross-walk using the software program LEGS (“Linking Equipercentile in a single Group or equivalent groups design”) [6]. LEGS was used to perform equipercentile linking on the total scores, with a third-order spline smoothing algorithm applied to the score distributions to minimize irregular fluctuations. The outcome of this procedure was a score conversion table (i.e., cross-walk) associating each possible WHO-5 total score (0–25) with an equivalent OMS score (0–50) based on their percentile ranks in our sample. To evaluate the linking accuracy, we computed the Root Mean Square Error of Linking [6]. ROC analysis for caseness cutoff. In addition to normative linking, we conducted a criterion-referenced analysis to determine an optimal OMS cutoff for detecting probable depression. We treated the WHO-5 as the gold-standard screener, defining “caseness” as WHO-5 < 13 (i.e., low well-being indicative of possible depression [28]). A Receiver Operating Characteristic (ROC) curve analysis examined how well the OMS total score could discriminate between participants with vs. without WHO-5 caseness. The ROC analysis computed the sensitivity (true positive rate) and specificity (true negative rate) of the OMS at every possible cutoff value. We identified the optimal cutoff using the Youden Index method, which selects the threshold that maximizes the sum of sensitivity and specificity (sensitivity + specificity – 1). This corresponds to the point on the ROC curve farthest from the 45° chance line [32, 15]. Once the optimal OMS cutoff was determined, we categorized individuals as at risk (below the cutoff; probable caseness) or not at risk (above the cutoff; non-caseness) for descriptive purposes. Reliable Change Index (RCI). We calculated the RCI for the OMS to provide a benchmark for meaningful individual change over time. The RCI [19] represents the minimum change in a client’s score that exceeds measurement error, at a chosen confidence level (95% in this study). In formula, RCI = 1.96 × √2 × SEM, where SEM = SD × √(1 – reliability). Because test–retest reliability of the OMS was not directly available (data were collected at a single time point) in this study, we used the instrument’s intraclass correlation coefficient (ICC) as an estimate of its temporal reliability, consistent with recommendations in the literature [29, 1, 5]. The OMS’s ICC was inserted into the RCI formula instead of test–retest reliability. To support both clinical decision-making and ensure robustness across different levels of clinical severity, we calculated RCI values using both the full study sample and its clinical subsample, defined as participants who scored below the caseness cutoff derived from the ROC analysis in this study. Results Equipercentile linking The OMS and WHO-5 demonstrated high internal consistency in our sample (Cronbach’s α = 0.93 and 0.94, respectively). The strong Pearson correlation between the two scales ( r = 0.80) further supported their suitability for equipercentile linking. We assessed the group invariance of the linking relationship across gender by computing the standardized Root Expected Mean Square Difference (REMSD). The REMSD was 5.9%, which is below the 8% criterion suggested by Dorans and Holland [12]. This result justified the use of a single, unified cross-walk for the entire sample. Using data from all 1,400 respondents, we generated a cross-walk table linking each WHO-5 score to an equipercentile-equivalent OMS score (see Table 2 ). According to this linked scale, a WHO-5 score of 13 – the conventional cutoff for possible depression or low well-being – corresponded to an OMS score of 33. To evaluate the linking accuracy, we calculated the Root Mean Square Error of Linking (RMSEL) for the OMS and WHO-5 relationship, which was 6.5 points. While Kolen and Brennan [24] propose that RMSEL should not significantly exceed SEM × √2 as a practical benchmark for acceptable linking error, and Dorans and Holland [12] noted that significant linking errors relative to measurement errors undermine the linking function’s adequacy, RMSEL values up to approximately 1.3–1.5 times SEM × √2 are often described as acceptable in practice. Based on these guidelines, our linking results were considered acceptable. Table 2 Cross-walk table on the WHO-5 and OMS WHO-5 score OMS score 0 6 1 9 2 12 3 15 4 17 5 20 6 22 7 24 8 25 9 27 10 28 11 30 12 31 13 33 14 34 15 36 16 37 17 39 18 41 19 42 20 44 21 46 22 47 23 48 24 50 25 50 ROC analysis The ROC analysis evaluated how well the OMS cutoff could detect individuals with WHO-5 caseness (WHO-5 < 13). The area under the ROC curve (AUC) was 0.90, indicating excellent discrimination between the low well-being (caseness) and normal well-being groups. According to conventional benchmarks, an AUC of 0.90 falls in the “outstanding” range for diagnostic accuracy [18]. Figure 1 shows the ROC curve, and Table 3 presents the sensitivity and specificity for various OMS cut scores. Based on the Youden Index, the optimal trade-off between sensitivity and specificity was achieved at an OMS total score of 31. Using a threshold of approximately 31 (out of 50) on the OMS to indicate probable caseness yielded a sensitivity of 0.88 and a specificity of 0.27. This means that 88% of those identified as at risk by the WHO-5 (score < 13) had OMS scores below 31, while 27% of those with WHO-5 in the non-caseness range had OMS scores at or above 31. Table 3 Results of ROC analysis using WHO-5 OMS Sensitivity Specificity Youden Index . . . . . . . . . . . . 21 0.99 0.70 1.30 22 0.99 0.65 1.34 23 0.99 0.61 1.38 24 0.98 0.57 1.41 25 0.97 0.52 1.45 26 0.96 0.45 1.51 27 0.95 0.39 1.56 28 0.93 0.35 1.58 29 0.91 0.31 1.60 30 0.88 0.27 1.61 31 0.85 0.23 1.62 32 0.82 0.20 1.62 33 0.78 0.17 1.61 34 0.74 0.14 1.60 35 0.69 0.11 1.58 36 0.65 0.08 1.56 37 0.60 0.07 1.54 38 0.54 0.05 1.49 39 0.49 0.04 1.45 . . . . . . . . . . . . Reliable Change Index The RCI was computed using the Jacobson–Truax method [19]. For the full study sample (n = 1,400), the OMS’s variability (SD = 10.35) and reliability (ICC = 0.92) yielded an RCI of 8.11 points. For the subsample in a clinical range (n = 665)—defined as participants scoring below the ROC-derived caseness cutoff of 31 points—the OMS’s variability (SD = 6.74) and reliability (ICC = 0.87) resulted in an RCI of 6.77 points. This suggests that within a population exhibiting potential clinical risk, such as clients undergoing counseling, a change of approximately 7 points is required to confidently infer actual change beyond measurement error (95% confidence level). Discussion This study established empirically derived interpretive benchmarks for the Outcome Measurement Scale (OMS), facilitating its use in both clinical practice and public mental health systems. Two key metrics were derived: (1) a caseness cutoff score of approximately 31–33, aligned with the WHO-5 threshold of 13 indicating low well-being, and (2) a Reliable Change Index (RCI) of approximately 8 points for the general adult population and 7 points for individuals in the clinical range (i.e., those scoring below the caseness threshold). Both analytic approaches used to derive the cutoff converged on a similar threshold, 31–33 points. Equipercentile linking indicated that the conventional WHO-5 cutoff score of 13 (used to flag low well-being and probable depression) corresponds to an OMS score of approximately 33, and the ROC analysis identified an optimal OMS cutoff around 31 (sensitivity = 0.88; specificity = 0.27). This convergence lends confidence that an OMS total score in the low 30s marks a clinically meaningful boundary between normal and at-risk well-being. The linking error (RMSEL) for the OMS and WHO-5 relationship was 6.5 points, and benchmarking against the OMS’s estimated measurement error (SEM ≈ 5.7) yielded a ratio of approximately 1.14, within acceptable bounds for linking error [24]. This finding suggests that using the cross-walked scores introduces minimal additional error, implying that the linked OMS scores can be used confidently instead of direct WHO-5 scores for identifying caseness. Regarding ROC analysis, the OMS demonstrated excellent accuracy in detecting those with probable depression-level well-being (AUC = 0.90, “outstanding” discrimination [18]). In practical terms, scoring below roughly 31 out of 50 on the OMS can be considered an indicator of poor mental well-being – analogous to the WHO-5 < 13 that signals need for further mental health evaluation. Notably, this cutoff lies well above the OMS scale midpoint, reflecting the instrument’s focus on positive well-being; even a moderately reduced sense of well-being (average item score around 6 out of 10) can place someone in the “at-risk” category. Given the public health intent of the OMS, the chosen cutoff prioritizes sensitivity over specificity – a deliberate trade-off to cast a wider net. By capturing approximately 88% of individuals with low well-being (minimizing false negatives) while accepting more false positives, the OMS functions as a high-sensitivity screener. This approach aligns with typical screening strategies, where identifying as many at-risk individuals as possible is often worth the cost of some over-identification. In community settings, those who screen positive (OMS below cutoff) can be further assessed to determine if intervention is warranted, whereas missing a truly at-risk person could mean a lost opportunity for early support. The relatively lower specificity (around 27%) indicates many who score below 31 on the OMS may not meet clinical diagnostic criteria; however, even these individuals are likely experiencing suboptimal well-being and could benefit from preventive resources or monitoring. Beyond establishing a caseness cutoff, this study also aimed to support both broad public health applications and individualized clinical decision-making by calculating two RCI values: approximately 8 points for the general adult population and 7 points for the clinical range (i.e., individuals scoring below the caseness cutoff). While clinicians working with counseling clients may more readily apply the 7-point threshold to assess reliable change, the RCI derived from the general population sample provides an important benchmark for evaluating changes in community-based psychoeducation or prevention programs. From a practitioner’s perspective, particularly when considering clients within the clinical range, score changes smaller than approximately 7 points on the 0–50 OMS scale should be interpreted with caution, as they may reflect random fluctuations. In contrast, changes equal to or exceeding this threshold are likely to reflect meaningful changes in psychological well-being. The estimated magnitude of reliable change aligns with established benchmarks for other widely used outcome measures, when scaled to their respective ranges. For example, an RCI of 6 points has been reported for the PHQ-9 (0–27), 5 points for the CORE-OM (0–40), and 6 points for the ORS (0–40), as noted in De Jong et al. [10]. Given the OMS’s high internal consistency ( α = 0.93) and its broad scoring range, an RCI of approximately 7 points for individuals within the clinical range and 8 points for the general population represents a psychometrically sound and practically useful threshold. From a clinical perspective, the OMS is exceptionally well-suited for routine outcome monitoring (ROM) systems due to its brevity. Crucially, the findings from this study equip the OMS with interpretable benchmarks that directly enhance clinical decision-making. First, clinicians can readily identify clients with baseline scores below the caseness cutoff (OMS < 31), signaling a need for additional assessment or early intervention. Second, the calculated RCI significantly strengthens the interpretive clarity of the OMS; a score change exceeding 7 points indicates a reliable improvement or deterioration at the individual level, ensuring that observed shifts are genuine and not merely due to measurement error. Third, the integration of both the RCI and the caseness cutoff provides a powerful framework for assessing therapeutic progress more comprehensively. For example, when a client’s OMS score changes by more than 7 points and simultaneously crosses the caseness threshold—such as moving from an initial score of 26 to a post-intervention score of 34—it can be considered a clinically significant recovery as conceptualized by Jacobson and Truax [19]. This dual-anchor system not only promotes more accurate and nuanced progress monitoring but also facilitates informed treatment planning and fosters collaborative decision-making throughout the entire course of therapy. Beyond clinical settings, the OMS also holds promise for public mental health applications. Its concise, interpretable format is well suited for community contexts, such as university or workplace wellness programs. The inclusion of both distress and well-being items helps reduce stigma and enhance acceptability in non-specialist settings. Because it is linked to the internationally validated WHO-5, the OMS enables cross-cultural benchmarking while remaining sensitive to local needs—for instance, Korea’s growing emphasis on early detection through its government-funded initiative, The National Mental Wellness Support Program [21]. At the policy level, OMS-based indicators such as recovery rates or the prevalence of low well-being can inform mental health dashboards, public funding decisions, and performance evaluations of service providers. This approach parallels outcome monitoring models such as the UK’s IAPT program. In regions where ROM adoption is limited—like South Korea [21]—the OMS addresses key implementation barriers by offering a brief, psychometrically sound, and logistically feasible alternative to traditional symptom-focused tools. Through its robust interpretive anchors (caseness cutoff and RCI), the OMS facilitates meaningful progress tracking, both at the individual level in therapy and the system level in public health evaluation. Limitations and Future Directions This study has a few limitations worth noting. First, our caseness cutoff for the OMS was based on the WHO-5, which, while a validated mental health screener, is not a diagnostic tool. Therefore, the OMS cutoff should be seen as identifying probable cases of low well-being, not confirmed mental disorders. Future research should explore how OMS scores align with formal diagnostic assessments, such as those based on DSM-5 criteria. Second, the sample we used to determine the cutoff comprised community adults, not specific clinical populations. Score distributions might differ in people actively seeking treatment, meaning the ideal cutoff for clinical caseness could be different depending on symptom severity. Further validation of the 31-point cutoff in clinical settings is needed to determine how well it generalizes. Third, because of our cross-sectional study design, our RCI estimation relied on intraclass correlation coefficients. Future studies should use test–retest reliability for a more precise RCI calculation. As the OMS is used more in practice, we encourage services to monitor real-world change distributions and recalibrate the RCI if needed. While the current RCI of approximately 7 points can help with clinical feedback, discharge decisions, and program evaluations, more research is needed to see if this threshold matches clinicians’ and clients’ subjective experiences of meaningful improvement. For example, qualitative studies exploring therapist and client feedback would help ensure the scale’s scoring thresholds are both psychometrically valid and practically intuitive. Conclusion This study provides empirically grounded interpretive anchors for the OMS, enhancing its applicability in routine outcome monitoring. A cutoff score of 31 and an RCI of 7 points offer an evidence-based framework for identifying individuals at risk and tracking meaningful therapeutic change. The OMS thus holds promise as a brief, psychometrically sound, and practically useful tool in both clinical and public health contexts. Its adoption may support the expansion of measurement-based care in South Korea and similar settings. Beyond its immediate utility, the OMS may also contribute to the global movement toward outcome-informed and client-centred care. Declarations Ethics approval and consent to participate This study was approved by the Institutional Review Board of Sogang University, Seoul, Korea (Approval No. SGUIRB-A-2308-28). All participants provided informed consent prior to participation. Funding This research was supported by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea (NRF) under the framework of the Leaders in Industry–University Cooperation 3.0 (LINC 3.0) program. The funders had no role in the design of the study, data collection, analysis, interpretation, or in writing the manuscript. Availability of data and materials N/A. Consent for publication N/A. Competing interests The authors declare no conflicts of interest. References Aldridge VK, Dovey TM, Wade A. Assessing test–retest reliability of psychological measures. European Psychologist . 2017;22(4):280–90. doi:10.1027/1016-9040/a000298. American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 4th ed. Washington (DC): American Psychiatric Publishing; 1994. Axelsson E, Österman S, Hedman-Lagerlöf E. 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National mind investment program: Monitoring and quality management plan (Research Report No. 2025-09). Sejong: Korea Institute for Health and Social Affairs; 2025. (in Korean). Kim H, Moon Y, Son B, Lee S, Roh H, Kim D. The utility of Korean version of the WHO Five Well-Being Index in evaluating depressive symptoms and quality of life in the aged dwelling in community. Journal of Korean Association for Geriatric Psychiatry . 2010;14(2):90–6. (in Korean). Kim S, Wang E. Validation of the Korean Inventory of the Clinical Outcomes in Routine Evaluation-Outcome Measure (K-CORE-OM). Korean Journal of Counseling . 2016;17(3):105–27. (in Korean). doi:10.15703/kjc.17.3.201606.105. Kolen MJ, Brennan RL. Test equating: Methods and practices . New York: Springer Science & Business Media; 2014. doi:10.1007/978-1-4419-9464-9. Lambert MJ. Outcome in psychotherapy: The past and important advances. Psychotherapy . 2013;50(1):42–51. doi:10.1037/a0030682. Lambert MJ, Whipple JL, Kleinstäuber M. Collecting and delivering progress feedback: A meta-analysis of routine outcome monitoring. Psychotherapy . 2018;55(4):520–37. doi:10.1037/pst0000167.27. Nunnally JC, Bernstein IH. Psychometric theory . 3rd ed. New York: McGraw-Hill; 1994. Topp CW, Østergaard SD, Søndergaard S, Bech P. The WHO-5 Well-Being Index: A systematic review of the literature. Psychotherapy and Psychosomatics . 2015;84(3):167–76. doi:10.1159/000376585. Weir JP. Quantifying test-retest reliability using the intraclass correlation coefficient and the SEM. Journal of Strength and Conditioning Research . 2005;19(1):231–40. doi:10.1519/R-15403.1. World Health Organization Regional Office for Europe. Wellbeing measures in primary health care: The DepCare project. Report on a WHO meeting . Copenhagen: World Health Organization Regional Office for Europe; 1998 [cited 2024 Sep 29]. Available from: https://iris.who.int/handle/10665/349766. Yon KJ, Jang HJ, Jin AY, Song YH, Cho HJ, Kim MJ, Kim CM, Lee MS. Development and validation of the Outcome Measurement Scale for routine outcome monitoring. Korean Journal of Counseling and Psychotherapy . 2025;37(2):475–501. (in Korean). doi:10.23844/kjcp.2025.05.37.2.475. Youden WJ. Index for rating diagnostic tests. Cance r. 1950;3(1):32–5. doi:10.1002/1097-0142(1950)3:13.0.CO;2-3. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 14 Oct, 2025 Reviewers agreed at journal 03 Oct, 2025 Reviewers invited by journal 25 Sep, 2025 Editor invited by journal 01 Sep, 2025 Editor assigned by journal 27 Aug, 2025 Submission checks completed at journal 27 Aug, 2025 First submitted to journal 25 Aug, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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07:24:59","extension":"xml","order_by":5,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":69815,"visible":true,"origin":"","legend":"","description":"","filename":"0750a9973fab46679dae4eb69538aa4b1structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7458113/v1/fa4f57e08914a42f41334801.xml"},{"id":93013298,"identity":"64ae80e0-b799-4fe2-abdd-a60d503147ca","added_by":"auto","created_at":"2025-10-08 07:24:59","extension":"html","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":80336,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7458113/v1/df68f639a3c61b9afab366c7.html"},{"id":93013292,"identity":"d6f5e2ff-d368-4aae-8356-e5bcf4e4c37f","added_by":"auto","created_at":"2025-10-08 07:24:58","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":58704,"visible":true,"origin":"","legend":"\u003cp\u003eROC curve for OMS caseness cutoff against WHO-5 standard\u003c/p\u003e\n\u003cp\u003eNote: OMS = Outcome Measurement Scale; WHO-5 = WHO-Five Well-Being Index. The ROC curve illustrates the sensitivity and specificity trade-off for varying OMS cutoff scores, using the WHO-5 threshold as the gold standard.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7458113/v1/cbb153ceb5cde17c0ee630c0.png"},{"id":93014726,"identity":"bf844639-4c36-4a1a-9715-fb63e7525a03","added_by":"auto","created_at":"2025-10-08 07:40:59","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":753237,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7458113/v1/976cf77a-c81a-4dfe-803f-3803271ea673.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Establishing a Caseness Cutoff and Reliable Change Index for the Outcome Measurement Scale","fulltext":[{"header":"Introduction","content":"\u003cp\u003eOver the past several years, particularly in the wake of the COVID-19 pandemic, public concern about mental health has grown substantially. In tandem, there have been increased demands for psychotherapy and counseling services to demonstrate effectiveness in a systematic and evidence-based manner. As an evidence-based practice, Routine Outcome Monitoring (ROM) has emerged as a widely endorsed strategy [25, 9]. ROM, also referred to as measurement-based care or feedback-informed treatment, generally involves three components: (1) collecting data from clients at regular intervals, (2) providing feedback based on the data to the therapist and, in many cases, to the client as well, and (3) using this feedback to adjust therapy when clinically appropriate. Numerous studies have shown that ROM can enhance treatment responsiveness, reduce client deterioration, and improve outcomes overall [26]. ROM is a cost-effective method that can enhance therapy outcomes with minimal additional cost [11].\u003c/p\u003e\u003cp\u003eDespite its proven utility, ROM remains underutilized in many real-world mental health settings—for example, only 14% of clinicians reported using ROM in routine practice in a national U.S. survey [20]—particularly in non-Western contexts such as South Korea [21]. One limiting factor has been the lack of brief and psychometrically sound outcome measures that are feasible for routine clinical use. In response to this gap, the Outcome Measurement Scale (OMS) was recently developed to support ROM in Korean clinical settings [31]. The OMS is designed to assess both multidimensional well-being and psychological distress, thus capturing both symptom reduction and well-being in a concise and clinically practical five-item format. Unlike symptom-focused measures such as the PHQ-9, which may not adequately capture clients’ perceptions of recovery (e.g., confidence, interpersonal harmony [8]), the OMS provides a more holistic view by assessing various domains of well-being—thereby offering greater insight into clients’ psychological recovery and personal growth. The OMS has demonstrated psychometric validity in a validation study conducted with a general adult sample of 1,400 participants across a wide age range. The scale showed strong evidence of construct validity and excellent internal consistency (Cronbach’s \u003cem\u003eα\u003c/em\u003e = 0.93).\u003c/p\u003e\u003cp\u003eTo support meaningful interpretation and clinical decision-making within ROM systems, the OMS requires two key interpretive anchors: a caseness cutoff score and a Reliable Change Index (RCI). The caseness cutoff represents a threshold below which a client is considered to be at potential clinical risk and may benefit from therapeutic intervention. Establishing such a cutoff enables clinicians to identify individuals in need of care and to benchmark symptom improvement or recovery over time. In parallel, the RCI provides a statistical index for determining whether the change in a client’s OMS score across time—such as from pre- to post-treatment—is greater than what could be attributed to measurement error alone [19, 5]. The RCI allows therapists to distinguish between reliable improvement, deterioration, and no meaningful change, thereby enhancing the precision of outcome feedback. In this study, we aimed to establish both the caseness cutoff score and the RCI for the OMS to enable its valid and practical use in ROM.\u003c/p\u003e\u003cp\u003eIn this study, the WHO-5 Well-Being Index was used as the primary reference instrument to derive the OMS cutoff. The WHO-5, developed by the World Health Organization, is a five-item, positively framed scale that measures subjective well-being, including emotional vitality, restfulness, and satisfaction with life [30]. It has been translated into over 30 languages and has been widely validated as both a general mental health indicator and a depression screener. A score of \u0026lt; 13 on the WHO-5 is commonly used to indicate low well-being or probable depressive caseness [28].\u003c/p\u003e\u003cp\u003eConceptually, the WHO-5 and OMS share overlap: both focus on functional and positive emotional aspects of well-being, rather than solely on clinical symptoms. The OMS includes dimensions of well-being related to psychological distress, self-concept, intimate relationships, work and role, and overall life satisfaction. This conceptual alignment was further supported by a strong empirical correlation in the present sample (\u003cem\u003er\u003c/em\u003e = 0.81), indicating substantial shared variance and convergent validity.\u003c/p\u003e\u003cp\u003eTo derive an empirically supported OMS cutoff, two complementary analytic methods were employed: equipercentile linking and Receiver Operating Characteristic (ROC) analysis. Equipercentile linking was used to determine the OMS score that corresponds to the same distributional position as a WHO-5 score of 13, thus providing a norm-referenced equivalence. ROC analysis, in contrast, was used to evaluate the diagnostic accuracy of the OMS score in predicting WHO-5 caseness status, estimating optimal sensitivity and specificity. Each method has unique advantages: equipercentile linking offers interpretability and normative consistency, while ROC analysis provides statistical rigor and classification accuracy. By combining both, the study aimed to derive a cutoff that is both practically meaningful and psychometrically robust.\u003c/p\u003e\u003cp\u003eTo calculate the OMS RCI, we applied the Jacobson–Truax method [19]. To enhance applicability across diverse settings, we derived two RCI values: one based on the general adult population and another based on the subsample within the clinical range. For counselors, the RCI derived from the clinical sample is particularly useful for tracking client progress during therapy. In contrast, the RCI based on the general population enables the scale to be applied in non-clinical, community-based contexts (e.g., schools, workplace wellness programs, and public health screenings). This dual approach supports the use of a single tool for both prevention and treatment purposes, thereby increasing its utility across a wide range of mental health service environments.\u003c/p\u003e\n\u003ch3\u003eStudy purpose\u003c/h3\u003e\n\u003cp\u003eThe primary aim of this study is to enhance the clinical utility of the OMS within ROM systems by establishing two key interpretive anchors. Specifically, this study seeks to establish a caseness cutoff score for the OMS using equipercentile linking and ROC analysis based on the WHO-5 Well-Being Index, and to calculate the RCI for the OMS with the full study sample and its subsample who scored below the caseness point of the OMS.\u003c/p\u003e\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003cdiv id=\"Sec4\" class=\"Section3\"\u003e\u003c/div\u003e\u003c/div\u003e\n\n\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\n\n"},{"header":"Methods","content":"\u003ch2\u003eStudy Design and Sample\u003c/h2\u003e\u003cp\u003e This study employed a single-group linking design in which all participants completed the OMS and WHO-5 measures. Single-group designs are considered robust for scale linking because the same individuals take both instruments, allowing direct score comparisons and strengthening the validity of the linking relationship. The sample consisted of 1,400 adults (50.7% male, 49.3% female) in South Korea, aged 20 to 69 years, recruited through a survey panel. The data were originally collected as part of the OMS validation study. Participants had a mean age of 39 years (SD = 15.3). By age group, 566 (40.4%) were in their 20s, 175 (12.5%) in their 30s, 213 (15.2%) in their 40s, 240 (17.1%) in their 50s, and 206 (14.7%) in their 60s. All participants provided informed consent prior to participation, and the study was approved by an institutional ethics review board.\u003c/p\u003e\u003ch3\u003eMeasures\u003c/h3\u003e\u003cp\u003e\u003cb\u003eOutcome Measurement Scale (OMS).\u003c/b\u003e The OMS is a recently developed brief outcome instrument consisting of 5 items that assess psychological distress and multidimensional well-being (covering self-concept, close relationships, work/role functioning, and overall life satisfaction). Each item is rated on an 11-point Likert scale from 0 (“very poor”) to 10 (“very good”), with higher scores indicating better well-being and less distress. Total scores range from 0 to 50. In the original validation, the OMS demonstrated excellent internal consistency (Cronbach’s \u003cem\u003eα\u003c/em\u003e = 0.93) and strong criterion validity, correlating highly (inversely) with established measures of distress (e.g., \u003cem\u003er\u003c/em\u003e = − 0.78 with the Korean Inventory of Clinical Outcomes in Routine Evaluation-Outcome Measure).\u003c/p\u003e\u003cp\u003e\u003cb\u003eWHO-5 Well-Being Index.\u003c/b\u003e The World Health Organization’s Five Well-Being Index (WHO-5) is a 5-item measure of subjective well-being. Each item is rated on a 6-point scale from 0 (“at no time”) to 5 (“all of the time”), assessing positive mood (e.g., “I felt cheerful and in good spirits”) and vitality over the past two weeks. Total scores range from 0 to 25, with higher scores reflecting better well-being. The WHO-5 has been widely validated as a screening tool for depression; a score \u0026lt; 13 is conventionally used to indicate low well-being or probable depressive caseness. In this study, we used the Korean version of the WHO-5 [20], which has shown high internal consistency in prior research (\u003cem\u003eα\u003c/em\u003e = 0.83–0.91) and was \u003cem\u003eα\u003c/em\u003e = 0.94 in our sample (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cdiv class=\"gridtable\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eDescriptive Statistics and Reliability\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"8\"\u003e\u003c/colgroup\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTest\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003enan\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMean\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eSD\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eSkew\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eKurt\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eCronbach \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\alpha\\:}\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eOMS\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1,400\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e30.80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e10.35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e-0.37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e2.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.93\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e710\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e31.16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e10.35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e-0.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e2.86\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eFemale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e690\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e30.43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e10.33\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e-0.26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e2.62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eWHO-5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1,400\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e12.01\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e6.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.00\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e2.14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.94\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e710\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e12.30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e6.19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e-0.03\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e2.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eFemale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e690\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e11.71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e5.94\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e2.20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"8\"\u003eNote: OMS = Outcome Measurement Scale; WHO-5 = WHO-Five Well-Being Index. Cronbach’s α values are presented for total scores.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003ch3\u003eAnalytical Procedures\u003c/h3\u003e\u003cp\u003e\u003cb\u003eEquipercentile linking.\u003c/b\u003e To establish a caseness cutoff on the OMS, we first conducted equipercentile linking with the WHO-5 as the reference instrument. Equipercentile linking aligns scores on two scales such that the linked scores have the same cumulative percentile rank in their respective distributions[3]. This approach produces a nonlinear score transformation (cross-walk) that equates each WHO-5 score with an OMS score having an equivalent percentile rank in the sample. Given that all participants completed both instruments, a single-group design was used. This design is ideal when the two tests measure similar constructs and have a high correlation (typically \u003cb\u003er ≥ 0.75–0.80\u003c/b\u003e). We also assessed group invariance of the linking relationship across gender by computing the standardized Root Expected Mean Square Difference (REMSD) for males vs. females.\u003c/p\u003e\u003cp\u003eWe generated the OMS and WHO-5 cross-walk using the software program LEGS (“Linking Equipercentile in a single Group or equivalent groups design”) [6]. LEGS was used to perform equipercentile linking on the total scores, with a third-order spline smoothing algorithm applied to the score distributions to minimize irregular fluctuations. The outcome of this procedure was a score conversion table (i.e., cross-walk) associating each possible WHO-5 total score (0–25) with an equivalent OMS score (0–50) based on their percentile ranks in our sample. To evaluate the linking accuracy, we computed the Root Mean Square Error of Linking [6].\u003c/p\u003e\u003cp\u003e\u003cb\u003eROC analysis for caseness cutoff.\u003c/b\u003e In addition to normative linking, we conducted a criterion-referenced analysis to determine an optimal OMS cutoff for detecting probable depression. We treated the WHO-5 as the gold-standard screener, defining “caseness” as WHO-5 \u003cb\u003e\u0026lt; 13\u003c/b\u003e (i.e., low well-being indicative of possible depression [28]). A Receiver Operating Characteristic (ROC) curve analysis examined how well the OMS total score could discriminate between participants with vs. without WHO-5 caseness. The ROC analysis computed the sensitivity (true positive rate) and specificity (true negative rate) of the OMS at every possible cutoff value. We identified the optimal cutoff using the Youden Index method, which selects the threshold that maximizes the sum of sensitivity and specificity (sensitivity + specificity – 1). This corresponds to the point on the ROC curve farthest from the 45° chance line [32, 15]. Once the optimal OMS cutoff was determined, we categorized individuals as at risk (below the cutoff; probable caseness) or not at risk (above the cutoff; non-caseness) for descriptive purposes.\u003c/p\u003e\u003cp\u003e\u003cb\u003eReliable Change Index (RCI).\u003c/b\u003e We calculated the RCI for the OMS to provide a benchmark for meaningful individual change over time. The RCI [19] represents the minimum change in a client’s score that exceeds measurement error, at a chosen confidence level (95% in this study). In formula, RCI = 1.96 × √2 × SEM, where SEM = SD × √(1 – reliability). Because test–retest reliability of the OMS was not directly available (data were collected at a single time point) in this study, we used the instrument’s intraclass correlation coefficient (ICC) as an estimate of its temporal reliability, consistent with recommendations in the literature [29, 1, 5]. The OMS’s ICC was inserted into the RCI formula instead of test–retest reliability. To support both clinical decision-making and ensure robustness across different levels of clinical severity, we calculated RCI values using both the full study sample and its clinical subsample, defined as participants who scored below the caseness cutoff derived from the ROC analysis in this study.\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003eEquipercentile linking\u003c/h2\u003e\u003cp\u003eThe OMS and WHO-5 demonstrated high internal consistency in our sample (Cronbach\u0026rsquo;s \u003cem\u003eα\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.93 and 0.94, respectively). The strong Pearson correlation between the two scales (\u003cem\u003er\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.80) further supported their suitability for equipercentile linking. We assessed the group invariance of the linking relationship across gender by computing the standardized Root Expected Mean Square Difference (REMSD). The REMSD was 5.9%, which is below the 8% criterion suggested by Dorans and Holland [12]. This result justified the use of a single, unified cross-walk for the entire sample.\u003c/p\u003e\u003cp\u003eUsing data from all 1,400 respondents, we generated a cross-walk table linking each WHO-5 score to an equipercentile-equivalent OMS score (see Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). According to this linked scale, a WHO-5 score of 13 \u0026ndash; the conventional cutoff for possible depression or low well-being \u0026ndash; corresponded to an OMS score of 33. To evaluate the linking accuracy, we calculated the Root Mean Square Error of Linking (RMSEL) for the OMS and WHO-5 relationship, which was 6.5 points. While Kolen and Brennan [24] propose that RMSEL should not significantly exceed SEM \u0026times; \u0026radic;2 as a practical benchmark for acceptable linking error, and Dorans and Holland [12] noted that significant linking errors relative to measurement errors undermine the linking function\u0026rsquo;s adequacy, RMSEL values up to approximately 1.3\u0026ndash;1.5 times SEM \u0026times; \u0026radic;2 are often described as acceptable in practice. Based on these guidelines, our linking results were considered acceptable.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eCross-walk table on the WHO-5 and OMS\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"2\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWHO-5 score\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eOMS score\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e22\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e25\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e27\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e28\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e31\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e33\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e34\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e36\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e37\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e39\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e41\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e42\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e44\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e46\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e47\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e48\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e50\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e50\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eROC analysis\u003c/h3\u003e\n\u003cp\u003eThe ROC analysis evaluated how well the OMS cutoff could detect individuals with WHO-5 caseness (WHO-5\u0026thinsp;\u0026lt;\u0026thinsp;13). The area under the ROC curve (AUC) was 0.90, indicating excellent discrimination between the low well-being (caseness) and normal well-being groups. According to conventional benchmarks, an AUC of 0.90 falls in the \u0026ldquo;outstanding\u0026rdquo; range for diagnostic accuracy [18]. Figure\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the ROC curve, and Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e presents the sensitivity and specificity for various OMS cut scores. Based on the Youden Index, the optimal trade-off between sensitivity and specificity was achieved at an OMS total score of 31. Using a threshold of approximately 31 (out of 50) on the OMS to indicate probable caseness yielded a sensitivity of 0.88 and a specificity of 0.27. This means that 88% of those identified as at risk by the WHO-5 (score\u0026thinsp;\u0026lt;\u0026thinsp;13) had OMS scores below 31, while 27% of those with WHO-5 in the non-caseness range had OMS scores at or above 31.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eResults of ROC analysis using WHO-5\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOMS\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSensitivity\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSpecificity\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eYouden Index\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" 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colname=\"c3\"\u003e\u003cp\u003e0.52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.45\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.96\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.51\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.95\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.56\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.93\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.58\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.91\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.60\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.88\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.61\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.62\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.82\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.62\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e33\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.78\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.61\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.74\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.60\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.58\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.65\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.56\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.07\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.54\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.49\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.45\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003cp\u003e.\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003ch3\u003eReliable Change Index\u003c/h3\u003e\n\u003cp\u003eThe RCI was computed using the Jacobson\u0026ndash;Truax method [19]. For the full study sample (n\u0026thinsp;=\u0026thinsp;1,400), the OMS\u0026rsquo;s variability (SD\u0026thinsp;=\u0026thinsp;10.35) and reliability (ICC\u0026thinsp;=\u0026thinsp;0.92) yielded an RCI of 8.11 points. For the subsample in a clinical range (n\u0026thinsp;=\u0026thinsp;665)\u0026mdash;defined as participants scoring below the ROC-derived caseness cutoff of 31 points\u0026mdash;the OMS\u0026rsquo;s variability (SD\u0026thinsp;=\u0026thinsp;6.74) and reliability (ICC\u0026thinsp;=\u0026thinsp;0.87) resulted in an RCI of 6.77 points. This suggests that within a population exhibiting potential clinical risk, such as clients undergoing counseling, a change of approximately 7 points is required to confidently infer actual change beyond measurement error (95% confidence level).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study established empirically derived interpretive benchmarks for the Outcome Measurement Scale (OMS), facilitating its use in both clinical practice and public mental health systems. Two key metrics were derived: (1) a caseness cutoff score of approximately 31\u0026ndash;33, aligned with the WHO-5 threshold of 13 indicating low well-being, and (2) a Reliable Change Index (RCI) of approximately 8 points for the general adult population and 7 points for individuals in the clinical range (i.e., those scoring below the caseness threshold).\u003c/p\u003e\u003cp\u003eBoth analytic approaches used to derive the cutoff converged on a similar threshold, 31\u0026ndash;33 points. Equipercentile linking indicated that the conventional WHO-5 cutoff score of 13 (used to flag low well-being and probable depression) corresponds to an OMS score of approximately 33, and the ROC analysis identified an optimal OMS cutoff around 31 (sensitivity\u0026thinsp;=\u0026thinsp;0.88; specificity\u0026thinsp;=\u0026thinsp;0.27). This convergence lends confidence that an OMS total score in the low 30s marks a clinically meaningful boundary between normal and at-risk well-being.\u003c/p\u003e\u003cp\u003eThe linking error (RMSEL) for the OMS and WHO-5 relationship was 6.5 points, and benchmarking against the OMS\u0026rsquo;s estimated measurement error (SEM\u0026thinsp;\u0026asymp;\u0026thinsp;5.7) yielded a ratio of approximately 1.14, within acceptable bounds for linking error [24]. This finding suggests that using the cross-walked scores introduces minimal additional error, implying that the linked OMS scores can be used confidently instead of direct WHO-5 scores for identifying caseness.\u003c/p\u003e\u003cp\u003eRegarding ROC analysis, the OMS demonstrated excellent accuracy in detecting those with probable depression-level well-being (AUC\u0026thinsp;=\u0026thinsp;0.90, \u0026ldquo;outstanding\u0026rdquo; discrimination [18]). In practical terms, scoring below roughly 31 out of 50 on the OMS can be considered an indicator of poor mental well-being \u0026ndash; analogous to the WHO-5\u0026thinsp;\u0026lt;\u0026thinsp;13 that signals need for further mental health evaluation. Notably, this cutoff lies well above the OMS scale midpoint, reflecting the instrument\u0026rsquo;s focus on positive well-being; even a moderately reduced sense of well-being (average item score around 6 out of 10) can place someone in the \u0026ldquo;at-risk\u0026rdquo; category.\u003c/p\u003e\u003cp\u003eGiven the public health intent of the OMS, the chosen cutoff prioritizes sensitivity over specificity \u0026ndash; a deliberate trade-off to cast a wider net. By capturing approximately 88% of individuals with low well-being (minimizing false negatives) while accepting more false positives, the OMS functions as a high-sensitivity screener. This approach aligns with typical screening strategies, where identifying as many at-risk individuals as possible is often worth the cost of some over-identification. In community settings, those who screen positive (OMS below cutoff) can be further assessed to determine if intervention is warranted, whereas missing a truly at-risk person could mean a lost opportunity for early support. The relatively lower specificity (around 27%) indicates many who score below 31 on the OMS may not meet clinical diagnostic criteria; however, even these individuals are likely experiencing suboptimal well-being and could benefit from preventive resources or monitoring.\u003c/p\u003e\u003cp\u003eBeyond establishing a caseness cutoff, this study also aimed to support both broad public health applications and individualized clinical decision-making by calculating two RCI values: approximately 8 points for the general adult population and 7 points for the clinical range (i.e., individuals scoring below the caseness cutoff). While clinicians working with counseling clients may more readily apply the 7-point threshold to assess reliable change, the RCI derived from the general population sample provides an important benchmark for evaluating changes in community-based psychoeducation or prevention programs.\u003c/p\u003e\u003cp\u003eFrom a practitioner\u0026rsquo;s perspective, particularly when considering clients within the clinical range, score changes smaller than approximately 7 points on the 0\u0026ndash;50 OMS scale should be interpreted with caution, as they may reflect random fluctuations. In contrast, changes equal to or exceeding this threshold are likely to reflect meaningful changes in psychological well-being.\u003c/p\u003e\u003cp\u003eThe estimated magnitude of reliable change aligns with established benchmarks for other widely used outcome measures, when scaled to their respective ranges. For example, an RCI of 6 points has been reported for the PHQ-9 (0\u0026ndash;27), 5 points for the CORE-OM (0\u0026ndash;40), and 6 points for the ORS (0\u0026ndash;40), as noted in De Jong et al. [10]. Given the OMS\u0026rsquo;s high internal consistency (\u003cem\u003eα\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.93) and its broad scoring range, an RCI of approximately 7 points for individuals within the clinical range and 8 points for the general population represents a psychometrically sound and practically useful threshold.\u003c/p\u003e\u003cp\u003eFrom a clinical perspective, the OMS is exceptionally well-suited for routine outcome monitoring (ROM) systems due to its brevity. Crucially, the findings from this study equip the OMS with interpretable benchmarks that directly enhance clinical decision-making. First, clinicians can readily identify clients with baseline scores below the caseness cutoff (OMS\u0026thinsp;\u0026lt;\u0026thinsp;31), signaling a need for additional assessment or early intervention. Second, the calculated RCI significantly strengthens the interpretive clarity of the OMS; a score change exceeding 7 points indicates a reliable improvement or deterioration at the individual level, ensuring that observed shifts are genuine and not merely due to measurement error. Third, the integration of both the RCI and the caseness cutoff provides a powerful framework for assessing therapeutic progress more comprehensively. For example, when a client\u0026rsquo;s OMS score changes by more than 7 points and simultaneously crosses the caseness threshold\u0026mdash;such as moving from an initial score of 26 to a post-intervention score of 34\u0026mdash;it can be considered a clinically significant recovery as conceptualized by Jacobson and Truax [19]. This dual-anchor system not only promotes more accurate and nuanced progress monitoring but also facilitates informed treatment planning and fosters collaborative decision-making throughout the entire course of therapy.\u003c/p\u003e\u003cp\u003eBeyond clinical settings, the OMS also holds promise for public mental health applications. Its concise, interpretable format is well suited for community contexts, such as university or workplace wellness programs. The inclusion of both distress and well-being items helps reduce stigma and enhance acceptability in non-specialist settings. Because it is linked to the internationally validated WHO-5, the OMS enables cross-cultural benchmarking while remaining sensitive to local needs\u0026mdash;for instance, Korea\u0026rsquo;s growing emphasis on early detection through its government-funded initiative, The National Mental Wellness Support Program [21].\u003c/p\u003e\u003cp\u003eAt the policy level, OMS-based indicators such as recovery rates or the prevalence of low well-being can inform mental health dashboards, public funding decisions, and performance evaluations of service providers. This approach parallels outcome monitoring models such as the UK\u0026rsquo;s IAPT program. In regions where ROM adoption is limited\u0026mdash;like South Korea [21]\u0026mdash;the OMS addresses key implementation barriers by offering a brief, psychometrically sound, and logistically feasible alternative to traditional symptom-focused tools. Through its robust interpretive anchors (caseness cutoff and RCI), the OMS facilitates meaningful progress tracking, both at the individual level in therapy and the system level in public health evaluation.\u003c/p\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eLimitations and Future Directions\u003c/h2\u003e\u003cp\u003eThis study has a few limitations worth noting. First, our caseness cutoff for the OMS was based on the WHO-5, which, while a validated mental health screener, is not a diagnostic tool. Therefore, the OMS cutoff should be seen as identifying probable cases of low well-being, not confirmed mental disorders. Future research should explore how OMS scores align with formal diagnostic assessments, such as those based on DSM-5 criteria.\u003c/p\u003e\u003cp\u003eSecond, the sample we used to determine the cutoff comprised community adults, not specific clinical populations. Score distributions might differ in people actively seeking treatment, meaning the ideal cutoff for clinical caseness could be different depending on symptom severity. Further validation of the 31-point cutoff in clinical settings is needed to determine how well it generalizes.\u003c/p\u003e\u003cp\u003eThird, because of our cross-sectional study design, our RCI estimation relied on intraclass correlation coefficients. Future studies should use test\u0026ndash;retest reliability for a more precise RCI calculation. As the OMS is used more in practice, we encourage services to monitor real-world change distributions and recalibrate the RCI if needed.\u003c/p\u003e\u003cp\u003eWhile the current RCI of approximately 7 points can help with clinical feedback, discharge decisions, and program evaluations, more research is needed to see if this threshold matches clinicians\u0026rsquo; and clients\u0026rsquo; subjective experiences of meaningful improvement. For example, qualitative studies exploring therapist and client feedback would help ensure the scale\u0026rsquo;s scoring thresholds are both psychometrically valid and practically intuitive.\u003c/p\u003e\u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study provides empirically grounded interpretive anchors for the OMS, enhancing its applicability in routine outcome monitoring. A cutoff score of 31 and an RCI of 7 points offer an evidence-based framework for identifying individuals at risk and tracking meaningful therapeutic change.\u003c/p\u003e\u003cp\u003eThe OMS thus holds promise as a brief, psychometrically sound, and practically useful tool in both clinical and public health contexts. Its adoption may support the expansion of measurement-based care in South Korea and similar settings. Beyond its immediate utility, the OMS may also contribute to the global movement toward outcome-informed and client-centred care.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Institutional Review Board of Sogang University, Seoul, Korea (Approval No. SGUIRB-A-2308-28). All participants provided informed consent prior to participation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was supported by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea (NRF) under the framework of the Leaders in Industry–University Cooperation 3.0 (LINC 3.0) program. The funders had no role in the design of the study, data collection, analysis, interpretation, or in writing the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;N/A.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;N/A.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;Competing interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;The authors declare no conflicts of interest.\u003c/p\u003e\n"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eAldridge VK, Dovey TM, Wade A. 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Nunnally JC, Bernstein IH. \u003cem\u003ePsychometric theory\u003c/em\u003e. 3rd ed. New York: McGraw-Hill; 1994.\u003c/li\u003e\n \u003cli\u003eTopp CW, \u0026Oslash;stergaard SD, S\u0026oslash;ndergaard S, Bech P. The WHO-5 Well-Being Index: A systematic review of the literature. \u003cem\u003ePsychotherapy and Psychosomatics\u003c/em\u003e. 2015;84(3):167\u0026ndash;76. doi:10.1159/000376585.\u003c/li\u003e\n \u003cli\u003eWeir JP. Quantifying test-retest reliability using the intraclass correlation coefficient and the SEM. \u003cem\u003eJournal of Strength and Conditioning Research\u003c/em\u003e. 2005;19(1):231\u0026ndash;40. doi:10.1519/R-15403.1.\u003c/li\u003e\n \u003cli\u003eWorld Health Organization Regional Office for Europe. \u003cem\u003eWellbeing measures in primary health care: The DepCare project. Report on a WHO meeting\u003c/em\u003e. Copenhagen: World Health Organization Regional Office for Europe; 1998 [cited 2024 Sep 29]. Available from: https://iris.who.int/handle/10665/349766.\u003c/li\u003e\n \u003cli\u003eYon KJ, Jang HJ, Jin AY, Song YH, Cho HJ, Kim MJ, Kim CM, Lee MS. Development and validation of the Outcome Measurement Scale for routine outcome monitoring. \u003cem\u003eKorean Journal of Counseling and Psychotherapy\u003c/em\u003e. 2025;37(2):475\u0026ndash;501. (in Korean). doi:10.23844/kjcp.2025.05.37.2.475.\u003c/li\u003e\n \u003cli\u003eYouden WJ. Index for rating diagnostic tests. \u003cem\u003eCance\u003c/em\u003er. 1950;3(1):32\u0026ndash;5. doi:10.1002/1097-0142(1950)3:1\u0026lt;32::AID-CNCR2820030106\u0026gt;3.0.CO;2-3.\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-psychology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"psyo","sideBox":"Learn more about [BMC Psychology](http://bmcpsychology.biomedcentral.com/)","snPcode":"","submissionUrl":"","title":"BMC Psychology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Routine outcome monitoring, Outcome Measurement Scale, reliable change index, caseness cutoff, linking","lastPublishedDoi":"10.21203/rs.3.rs-7458113/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7458113/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Routine Outcome Monitoring (ROM) is an evidence-based approach that enhances psychotherapy outcomes by systematically tracking client progress. However, its implementation in real-world practice—particularly in non-Western settings—remains limited, partly due to a lack of brief and interpretable outcome measures. The Outcome Measurement Scale (OMS) was developed to address this gap by assessing both psychological distress and multidimensional well-being in South Korea. This study aimed to establish two key interpretive anchors for the OMS: a caseness cutoff score and a Reliable Change Index (RCI) to support its clinical and public health applications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e A sample of 1,400 adults from South Korea completed both the OMS and the WHO-5 Well-Being Index, a validated measure of subjective well-being. Equipercentile linking and Receiver Operating Characteristic (ROC) analysis were employed to identify the OMS score corresponding to the WHO-5 caseness threshold (\u0026lt; 13). The RCI was calculated using the Jacobson–Truax method based on estimated measurement error and internal consistency reliability.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Equipercentile linking indicated that a WHO-5 score of 13 corresponded to an OMS score of 33, while ROC analysis identified 31 as the optimal cutoff (AUC = 0.90; sensitivity = 0.88; specificity = 0.27). The OMS and WHO-5 demonstrated strong correlation (\u003cem\u003er\u003c/em\u003e= 0.80). The RCI was calculated as 8.11 points for the full sample and 6.77 points for the clinical subsample, suggesting that a change of approximately 7–8 points reflects statistically reliable improvement or deterioration at the 95% confidence level.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e An OMS score of approximately 31 serves as a practical caseness threshold, while a 7–8 point change represents reliable individual change. These interpretive benchmarks enable clinicians and public health professionals to screen for low well-being, track meaningful change, and evaluate service outcomes using the OMS. The findings highlight the OMS as a brief and useful tool for ROM implementation in both clinical and community mental health settings.\u003c/p\u003e","manuscriptTitle":"Establishing a Caseness Cutoff and Reliable Change Index for the Outcome Measurement Scale","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-08 07:24:54","doi":"10.21203/rs.3.rs-7458113/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2025-10-14T11:22:37+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"52234663716397488408119912014395590760","date":"2025-10-03T12:10:10+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-09-25T14:37:36+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-09-01T10:37:55+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-08-27T04:35:34+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-08-27T04:34:16+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Psychology","date":"2025-08-26T02:59:43+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-psychology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"psyo","sideBox":"Learn more about [BMC Psychology](http://bmcpsychology.biomedcentral.com/)","snPcode":"","submissionUrl":"","title":"BMC Psychology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"5e55ee21-8a10-4ed3-bc6c-a51702bac61f","owner":[],"postedDate":"October 8th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-10-08T07:24:54+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-08 07:24:54","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7458113","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7458113","identity":"rs-7458113","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}