Digitizing Paper-based Military health records from Norwegian males born in 1950 – assessments of data quality and applicability in research

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Background Archived military documents contain health information that can enrich the Norwegian Armed Forces Health Registry (NAFHR) with more detailed clinical measurements of older birth cohorts. However, uncertainty exists about the preservation of digital reproduction and the accuracy of clinical measurements for research purposes. Methods To establish an infrastructure at the National Archives of Norway, we digitized military health information covering approximately 60% (n = 17 324) of Norwegian men born in 1950. Health records were manually transcribed, and transcribed data were controlled for registered data in the NAFHR. Clinical measures were compared with results from comparable national health surveys, and variations between the conscription board health examinations and the examinations on the first day of service were explored. Transcribed cardiovascular disease (CVD) risk factor data were tested with logistic regression models to assess their predictive ability. Results The transcribed data showed good compliance and readability, with overall accurate and valid clinical measurements. While some variations existed between the two examination settings, the measurements generally aligned with the national health survey results. Several of the CVD risk factors in the cohort showed the expected associations with CVD mortality. Conclusion This study highlights the readability and accuracy of digitized military health data, emphasizing its potential for public health and future research through the NAFHR. Further digitization efforts promise enhanced communication and expanded research opportunities. The Norwegian Armed Forces Health Registry (NAFHR) Historical archives Conscription data Quality control Military Digitization Figures Figure 1 Figure 2 Figure 3 Figure 4 Highlights Digitizing lost or omitted information can enhance an existing registry. The digitization of military archives can open possibilities for future research. Summary table What was already known about the topic The Norwegian Armed Forces Health Registry (NAFHR) serves as a national health registry for data collected during military service, but information on Norwegian males born before or in the 1950s is missing. Through collaboration with the National Archives of Norway, we discovered paper-based military archives containing health information for cohorts with insufficient data. There were uncertainties regarding the preservation of these archives for digital reproduction and the accuracy of clinical measurements for research purposes. What this study added to our knowledge Quality control and comparison with data from the NAFHR and national health surveys revealed good compliance and readability of the transcribed material. This digitization enriches the existing registry (NAFHR in our case), thereby expanding possibilities for future research. 1. INTRODUCTION In Norway, conscription to military service is a guiding principle in the social contract between the country's citizens and the state. Eligible men and women must attend a military board health examination to determine their fitness for duty ( 1 ). The conscription board health examination (CBHE) prior to service consisted of clinical examinations and tests of physical and mental health, following standard guidelines of the Norwegian Armed Forces Joint Medical Services. These military medical screening procedures were established in the 1950s and have not changed much over time ( 2 ). The data collected at the CBHE are stored in the Norwegian Armed Forces Health Registry (NAFHR). This national health registry was established in 2005 and is used for monitoring the health status of military personnel through their service ( 3 ). Data from the Armed Forces Personnel Database, the Military Electronic Medical Records System, and the Norwegian Cause of Death Registry were regularly entered into the NAFHR. The data collected in the registry span over 5 decades with nearly complete national coverage. However, most military personnel born before 1950 are not registered in the NAFHR. Furthermore, information on height, weight and general cognitive ability is missing for up to 30% of the registered men born in 1950, despite being the first cohort for which such information was registered in the NAFHR. The data loss can, at least partly, be explained by the Armed Forces’ archive procedures. A military electronic personnel database was adopted in 1992; before that time, military records were paper-based and kept within personnel files that were handed over to the National Archives of Norway when the person turned 70 years old. Therefore, the electronic database does not encompass the entire older conscript population, and some of the most detailed clinical data are still stored in papers at the National Archives only. A search at the National Archives showed that paper-based military archives contained health information for at least 50–60% of Norwegian men born between 1941 and 1957 and that military service cards were tagged with an 11-digit personal identification number unique to every Norwegian individual ( 4 ). This discovery presented an opportunity to expand and update the electronically searchable information in the NAFHR by digitizing the military archives. However, the consistency and accuracy of the data were unknown. This paper aims to present military health data that have been retrieved and transcribed from archived personnel files belonging to Norwegian men born in 1950—the first birth cohort registered in the NAFHR—to evaluate the quality of the data and suggest opportunities for research. 2. MATERIALS AND METHODS 2.1 Military personnel files belonging to Norwegian men born in 1950 stored in the National Archives (98 words) In 1950, 32 203 boys were born in Norway ( 5 ). The Norwegian conscription law obliged them all to attend a CBHE when they reached the age of 18–19 years to determine their fitness for military service ( 6 ). Approximately 6–7% of the birth cohorts were exempted before the CBHE, mainly because of death, emigration, disabling diseases, or crime ( 7 , 8 ). The National Archives in Oslo stored military service records from 17 324 Norwegian men born in 1950 [Figure 1 ], hereinafter referred to as “the digitized 1950 cohort”. 2.2 Examinations conducted at the conscription board and on the first day of service Since 2010, CBHEs have been conducted at ten regional centers that are specially equipped for military medical examinations. However, in 1968-69, CBHEs were conducted locally in municipalities across the country [Figure 2 ]. For our review, we categorized the military conscription sites into 19 groups that corresponded with the former Norwegian county classification (1946–2018) [9] [Figure 2 , STable 1]. The local police districts or assembly halls were venues for conscription summoning, while military doctor teams travelled around the country with medical equipment for measuring. The CBHEs and first day-in-service health examinations (FDHEs) were performed according to instructions provided by the Armed Forces Joint Medical Services ( 9 ). Height and weight were measured to the nearest centimeter (cm) and kilogram (kg), respectively. Systolic and diastolic blood pressure (SBP and DBP) were measured in mm Hg on the right upper arm after 5 minutes of seated rest using an appropriately sized cuff and manual sphygmomanometer. The resting heart rate was measured by pulse palpation as beats per minute. Furthermore, the physical health assessment consisted of a clinical interview, a review of the candidate’s personal statements of health, and any medical documentation of disease. A test for cognitive ability, introduced in 1954 and referred to as “general ability” (GA) in the CBHE, consisted of three different subtests: numeracy, word similarity, and figure. The Stanine scores of GA (short for “Standard Nine”) range from 1 (worst) to 9 (best). A more detailed description of the tests and scores can be found elsewhere ( 2 , 10 ). 2.3 Digitized information of the 1950 cohort In the Supplement, there are examples of medical documents that were commonly preserved in the personnel files and digitized [SFigure 1–4]. Among a great variety of conserved military medical forms, we chose to review and transcribe selected information from the conscripts’ structured medical journal [SFigure 1] and the GA test [SFigure 2]. In cases where both the medical journal and the GA test were missing, we digitized this information (if available) from the military service records [SFigure 3]. Self-declaration of health [SFigure 4] included information about health conditions in childhood and the family [STable 2]. The following information was selected for transcription: place and date of the military medical examination, height (cm), weight (kg), SBP and DBP, heart rate per min, and GA-scores (stanine score and the scores from each of the three subtests). 2.4 Transcription process The data were manually transcribed into an Access database according to a codebook developed in the pilot phase of the project. Seven employees participated in the transcription, and the employees were all given training by the same personnel and used the same codebook and database. In the quality control of the transcription process, the 11-digit personal identification number was linked to the Norwegian Population Registry to identify and correct erroneous registrations. The transcribing staff regularly reviewed the transcribed data for any outlier values and corrected them. Once the transcribing task was over, members of the project group who had not been involved in transcribing rereviewed the data for unrealistic values/records and verified the accuracy of these values by comparing them with the original documents. Numeric values were checked for any extreme values, while nonnumeric values, such as dates, were checked for errors. A total of 103 transcribed cases with outlying numbers and unrealistic information were identified. The information in the personnel files was reviewed and corrected for 51 cases. The remaining 52 cases were found to have been transcribed correctly, although those numbers were unrealistic. These were attributed to errors made by the doctors, illegible handwriting, or poor quality of the original documents. To assess the reliability of our transcribing process, we conducted an intra-investigator reproducibility test to determine whether the same records would be transcribed differently by different staff. We randomly selected 100 men from the cohort and compared the transcriptions of two different staff members. Out of the 1800 total transcribed values, only 38 (2.1%) deviated between the two staff members; among these, 25 deviating records were due to mistakes (n = 22) and different transcribing due to individual interpretation of records (n = 3). The remaining discrepant records were attributed to illegible handwriting, doctors’ mistakes, and poor document conditions. 3. RESULTS 3.1 Quality control of the transcribed data Of the 17 324 men who participated in CBHE, 85% had recorded weight data, and 75% had recorded heart rate data [Table 1 ]. Unfortunately, major conscription sites in western Norway did not record weight during this period. In total, 15 790 men (91%) also had health records at FDHE [Figure 2 ]. Heart rate at the FDHE was rarely recorded (missing n = 12 076), as the doctors left this section empty or wrote "RM" (regular) in most cases. Table 1 Descriptive statistics on Norwegian men born in 1950 based on information transcribed from 17 324 military health records at the National Archives of Norway. Number of men (% of 17 324) Min–Max Mean (SD) Median Skewness Kurtosis Conscription board health examination (CBHE) Place 16 269 (94) Year 16 574 (96) 1966–1976 1969 (0.3) 1969 - - Height, cm 17 028 (98) 151–205 178.8 (6.2) 179 -0.1 * 3.1 * Weight, kg 14 718 (85) 41–123 68.6 (8.3) 68 0.7 * 4.7 * Heart rate, beats per minute 12 988 (75) 40–120 72.1 (8.3) 72 0.7 * 5.1 * SBP, mm Hg 16 040 (93) 85–200 127.6 (11.5) 125 0.8 * 4.5 * DBP, mm Hg 16 046 (93) 30–120 77.2 (8.6) 80 -0.3 * 3.5 * GAstanine score 15 885 (92) 0–9 5.9 (1.7) 6 -0.2 * 2.5 * - Numeric test 14 021 (81) 0–30 18.8 (5.2) 20 -0.5 * 2.6 * - Word similarity test 14 018 (81) 0–36 25.7 (4.3) 26 -1.0 * 5.2 * - Figure test 14 034 (81) 0–54 31.9 (10.9) 32 -0.2 * 2.2 * First day in service health examination (FDHE) Year 15 790 (91) 1967–1980 1970 (1.3) 1970 - - Height, cm 11 082 (64) 152–205 178.9 (6.2) 179 0.0 3.0 Weight, kg 13 054 (75) 46–124 70.6 (9.0) 70 0.8 * 4.8 * Heart rate, beats per minute 3714 ( 21 ) 48–138 77.3 (11.5) 76 1.1 * 5.1 * SBP, mm Hg 11 951 (69) 80–230 133.3 (13.6) 130 0.7 * 4.1 * DBP, mm Hg 11 989 (69) 35–130 80.4 (9.0) 80 0.2 * 3.8 * * indicates a p value < .05 in the skewness and kurtosis test for normality. When examining the records of the conscripts for which there were significant differences between CBHE and FDHE, 312 discrepant cases were found, and 123 registrations were corrected by reviewing the registrations. The remaining 189 possibly erroneous registrations were attributed to the same reasons as described earlier. During the examination, minor changes in height and weight were found between these two time points, as FDHEs are usually present one year after CBHEs [Table 2 ]. Table 2 Comparisons * of height and weight records measured at the conscription board health examinations (CBHE) one year prior to military service and on the first day in military service (first day health examinations, FDHE) transcribed from military health records at the National Archives of Norway. Number of men with discrepant records between CBHE and FDHE Mean difference (SD) Median difference (10th to 90th percentile) Min to Max difference Days from CBHE to FDHE 15 647 615 (456) 495 (217 to 1156) -197 to 4148 Difference in height (cm) 10 941 0.1 (1.7) 0 (-2 to 2) -20 to 22 Difference in weight (kg) 11 254 2.2 (3.8) 3.8 (-2 to 7) -19 to 30 * Differences were computed by subtracting the CBHE values from the FDHE values We cross-referenced the transcribed height, weight, and GA-staninescores with the records that were already available in the NAFHR. Among the 17 324 conscripts, 16 551 had CBHE heights recorded in the NAFHR, but only 705 had CBHE weights recorded in the NAFHR [Table 3 ]. This comparison enabled us to uncover disparities between the two databases, expecting no differences between the transcribed records and measurements registered in NAFHR. Overall, the number of discrepancies in the records between the two databases was low, except for weight records. This discrepancy arose because the weight records of the NAFHRs included decimals, which differed from the format of the transcribed weight records. Table 3 Height, weight, and general ability (GA-staninescores) transcribed from military health records at the National Archives of Norway and compared to* registrations in the Norwegian Armed Forces Health Registry (NAFHR). Number of men with comparable registration records Number (% § ) of men with discrepant registrations Mean discrepancies (SD) Median (10th to 90th percentile) Min to Max discrepancy Height (cm) 16 551 610 (3.7) 0 (0.85) 0 (0 to 0) -30 to 20 Weight (kg) 705 278 (39.4) 0.85 (3.2) 0 (-0.5 to 4) -20 to 33 GA-stanine score 14 809 145 ( 1 ) 0 (0.23) 0 (0 to 0) -5 to 6 * Discrepancies were computed by subtracting the transcribed values from the values registered in the NAFHR. § The number of men with discrepancies was divided by the number of men with comparable registration records in a measurement variable. 3.2 Descriptive statistics To explore the variance of the transcribed data and assess whether the records were accurate enough for research purposes, we used descriptive statistics of the digitized 1950 cohort on height, weight, SBP, DPB, heart rate, and GA-stanine score [Table 1 ]. Overall, the mean blood pressure and heart rate were greater at FDHE than at CBHE. The heart rate, SBP, and DBP at CBHE clustered around some specific values. For example, 43% of the total observations in CBHE-DBP had a value of 80 mm Hg, and 32% of the CBHE-SBP was 120 mm Hg [Figure 3 ]. Similarly, 23% of the CBHE heart rate patients had a heart rate of 72 bpm [Figure 4 ]. The mean GA-stanine score for the cohort was 5.9 points, with an SD of 1.7. The transcribed height, weight, and blood pressure data were compared to the means, SDs, and medians of similar published data from surveys conducted on young men in Scandinavia ( 11 – 13 ). The means and SDs of transcribed height and weight records were comparable to those of the cohorts in these surveys. We observed smaller SDs for SBP, DBP, and heart rate at the CBHE than at the FDHE and population surveys, while each of the means were comparable to those of other health surveys [Table 4 ]. Table 4 Overview of information transcribed from military health records at the National Archives of Norway and registrations in the Norwegian Armed Forces Health Registry (NAFHR) and population health surveys on young men in Norway. Source Digitized personnel files stored at the National Archives The Norwegian Armed Forces Health Registry Population health surveys Region National National Tromsø municipality Finnmark F , Sogn og Fjordane SF and Oppland O counties Examination year 1969 (range 1966–1976) 1969 (range 1966–1990) 1974( 11 ) 1986-87( 12 ) 1974–78( 13 ) Birth cohort 1950 1950 1950–1954 1957–1966 1950–1956 Participants 1 CBHE n = 17 324 2 FDHE n = 15 790 n = 25 770 n = 502 n = 2380 n = 449 F , n = 226 SF , n = 412 O 3 Mean 4 Median 3 Mean 4 Median 3 Mean 4 Median 3 Mean 4 Median 3 Mean 4 Median Age/Age range 18.9 (0.5) 18.7 [18.4–19.3] 20.5 (1.3) 20.2 [19.4–22.1] 19.2 (2.7) 18.6 [18.1–20.4] 20–24 20–29 20–24 20–24 Height (cm) 178.8 (6.2) 179 [171–187] 178.9 (6.2) 179 [171–187] 178.6 (6.3) 179 [170–187] 174.1 (6.9) F 178.4 (5.8) SF 178.6 (5.4) O Weight (kg) 68.6 (8.3) 68 [59–79] 70.6 (9.0) 70 [60–82] 70.9 (9.9) 70 [60– 83] 69.5 (8.2) F 71.7 (8.9) SF 74.1 (9.9) O GA-staninescore 5.9 (1.8) 6 [4–9] 5.8 (1.8) 6 [3–8] SBP (mm HG) 127.6 (11.5) 125 [115–140] 133.3 (13.6) 130 [120–150] 124.5 (13.3) 133.9 (13.0) F 132.9 (14.0) SF 134.3 (13.3) O 132 (118–150) F 132 (114–150) SF 134 (120–152) O DBP (mm Hg) 77.2 (8.6) 80 [60–95] 80.4 (9.0) 80 [70–90] 73.8 (11.3) 75.0 (10.0) F 74.7 (10.8) SF 75.1 (10.3) O 76 (62–88) F,SF,O Heart rate (bpm 3 ) 72.1 (8.3) 72 [60–80] 77.3 (11.5) 76 [64–92] 71.0 (12.5) 1 CBHE=Conscription board health examination 2 Health examinations conducted at the first day in military service (first day health examinations FDHE) 3 Mean represents the mean (standard deviation), and 4 Mediancorresponds to the median [10th − 90th percentile]. 5 Beats per minute. 3.3 Assessing transcribed data in statistical models for cardiovascular disease mortality We performed a series of statistical tests to investigate features of the digitized 1950 cohort related to cardiovascular disease (CVD) mortality. By linking data on the underlying cause of death registered in the Norwegian Cause of Death Registry, we included deaths that occurred from the year of CBHE to the end of 2021. The EU shortlist for Causes of Death, which ensures comparability over time, was used to identify the underlying cause of death, and CVD deaths were defined using codes 44–50 from the list ( 14 , 15 ). First, we assessed whether the proportion of deaths from CVD among all deaths differed between two samples: the digitized 1950 cohort (n = 17 324) and all the individuals born in 1950 who were registered in the NAFHR (n = 25 770). Among the digitized cohort, 23.6% died from CVD, whereas 21.6% of those born in the same year from NAFHR did, resulting in a 2% difference in the proportions (p = 0.03) [STable 3]. Next, we used two multivariable logistic regression models to examine whether some of the transcribed information that could be considered CVD risk factors would demonstrate the expected predictive relationships with CVD mortality. Four independent variables were selected based on known associations with CVD ( 16 , 17 ): higher risk of CVD mortality with lower GA-stanine scores (continuous), higher body mass index (BMI) (continuous), and higher SBP and DBP (groups relative to the normal range). SEP and DBP were categorized into four groups based on a Swedish study of male conscripts born between 1949 and 1951 ( 16 ) [STable 4]. The CBHE model involved 11 581 conscripts with complete information on the four selected variables. The FDHE model included 7367 conscripts selected for military service, providing the aforementioned information during their FDHE and a GAstaninescore from the CBHE. Table 5 Odds ratio (95% confidence intervals) for CVD mortality (from the year of CBHE until 2021) based on information transcribed from military health records stored at the National Archives of Norway Odds ratio (95% CI) CVD risk factors CBHE (n = 11 581) FDHE (n = 7367) GA stanine score per 1 unit 0.86 (0.82–0.90) * 0.86 (0.80–0.91) * BMI per 1 kg/m 2 1.11 (1.07–1.15) * 1.10 (1.06–1.15) * SBP, mm Hg < 115 1.24 (0.86–1.77) 1.06 (0.57–1.97) 115 to < 125 ref ref 125 to < 135 0.83 (0.67–1.04) 1.11 (0.80–1.55) ≥ 135 0.86 (0.68–1.09) 1.04 (0.75–1.44) DBP, mm Hg < 65 0.76 (0.52–1.11) 0.28 (0.09–0.90) * 65 to < 75 ref ref 75 to < 85 0.82 (0.66–1.03) 0.96 (0.69–1.33) ≥ 85 1.10 (0.84–1.45) 1.27 (0.90–1.79) * : p value < 0.05 The associations between the GA-stanine score and CVD mortality, as well as between BMI and CVD mortality, remained consistent between the two models [Table 5 ]. This indicated that those with a higher GA-stanine score or lower BMI were at lower risk of CVD mortality. Regarding the association between blood pressure and CVD mortality, only the lowest DBP group in the FDHE model demonstrated a significantly lower risk of CVD mortality (OR = 0.28, 95% CI: 0.09–0.90). While most of the numeric effect estimates of the higher SBP groups in the CBHE model implied a lower risk of CVD mortality compared to the reference, higher SBP groups in the FDHE implied higher CVD mortality. For DBP, the numeric OR effect estimates had a similar direction in the CBHE and FDHE models. 4. DISCUSSION This paper describes the digitization of military paper-based archives covering approximately 60% of all Norwegian men born in 1950. We assume that the cohort represents the healthy and normally skilled proportion of men born in 1950. This assumption was strengthened by the finding of normally distributed health data that were comparable to the data found in population health surveys in the same age group and by the fact that few men died before 2021. Approximately 6.4% of males in the 1950-born cohort did not attend CBHE and were not included in the cohort. The files belonging to those who died or were deemed unfit for further military service after having conducted basic military training were stored in archives that were not subjected to our review. The same archive procedure was also applied to men who became officers or military police or who refused military service for ethical reasons. An extended review of more archives could further increase the generalizability of the digitized cohort. Unfortunately, as there has been no absolute safeguarding of the military archives, we must consider that some of the personnel files and some of the documents stored within the files may have been lost. Overall, we found that the information we selected for digitization was consistently recorded in the military health records and was accurately transcribed. This indicates that these records were well preserved and easily readable. Missing records from FDHE should be considered a limitation, as measurements from two separate times would have provided an opportunity to assess the quality of the measurements as well as determine true changes in health between two time points. We speculate that doctors may only have recorded FDHE information if it differed from the CBHE measures. In approximately 1968-69, when the men in the digitized cohort were summoned to CBHE, the medical examination procedures were much the same as they are today, but the setting and locations differed. Currently, there are 10 stationary locations for conscript examinations in Norway; however, in the archived material, we registered 141 different locations across the country. While some of the locations were stationary and located in military facilities, the majority operated on a temporary basis. This arrangement may have introduced some variability since military doctors had to travel with measurement equipment to different locations, and a larger number of medical staff were performing measurements. Nevertheless, the regional differences in the clinical measurements (not presented) were consistent with known differences in height and weight observed in other studies ( 7 , 18 , 19 ). To determine whether the data were accurate enough for research purposes, we used a range of methods, including examining inconsistencies within the transcribed and already registered data, comparing data with results in similar populations, and conducting statistical analyses. The digitized 1950 cohort data demonstrated high reliability and validity. This was supported by the minimal discrepancies between measures recorded at two different time points for military health examinations for the same individuals, the consistency with existing NAFHR records, and the predictive accuracy of CVD mortality. Several Nordic studies have been carried out to investigate conscription databases and utilize conscription records for epidemiological studies ( 16 , 17 , 20 – 25 ). Despite the differences in the aims of the studies and the inclusion criteria, it is worth noting that the findings from our statistical analysis aligned with the outcomes of these prior studies ( 17 , 23 ). However, our findings did not show the expected consistent association between higher SBP and DBP levels and CVD mortality and differed from previous studies that revealed the influence of both SBP and DBP on CVD mortality ( 16 , 24 ). We noticed that the process of measuring and recording blood pressure in military examination settings might have been imprecise. Clinicians might have been instructed to round up their records or might have had preferences for specific numbers. Notably, in measurements taken at CBHE, as depicted in Fig. 3 , the clustering of SBP and DBP values around certain numbers suggests rounding to the nearest 5 or 10 mmHg, potentially leading to an underestimation of associations ( 16 ). This may indicate that the measurements of SBP and heart rate at the CBHE examination are of somewhat lower quality than the measurements collected on the FDHE or in a health survey. Differences in the competence requirements and procedures between the military health personnel at CBHE and FDHE could lead to more imprecise CBHE measurements. 5. CONCLUSION This review included health records stored at the National Archives of Norway from the 1950 male birth cohort of Norway. The assessment of the transcribed material showed conformity with the source documents. The results support that the digitization of military personal files stored at the National Archives of Norway can enhance a national health registry by the inclusion of information that has been lost or was not included in the registry. The military personnel files and documents that have been handed over to the National Archives must be considered unique data sources, both in the Norwegian context and in the international context. There is great interest in these data for long-term studies of dementia, cardiovascular diseases, and obesity, among others. The digitization of these data can facilitate more effective communication and research on public health as well as for veteran affairs by linking them to other national health registries and opening possibilities for longitudinal research. Abbreviations BMI: Body mass index CBHE: Conscription board health examination CI: Confidence interval Cm: Centimeter CVD: Cardiovascular disease DBP: Diastolic blood pressure FDHE: First day of service health examination GA: General ability ICD: International Classification of Diseases kg: Kilogram mm Hg: millimetre of mercury NAFHR: Norwegian Armed Forces Health Registry SBP: systolic blood pressure Declarations Ethical approval This investigation, as a quality control project, was not required to obtain approval from the Regional Committees for Medical and Health Research Ethics (REK). The work is authorized in the Regulations for the Norwegian Armed Forces Health Registry (NAFHR) and is carried out by employees of the NAFHR who are authorized to process the data without the data subjects' consent according to the Health Register Act, regulations, and security manual for the NAFHR. Consent for publication Not applicable Availability of data and materials The datasets generated and/or analysed during the current study are not publicly available but are available from the NAFHR with necessary approval. Competing interests The authors declare that they have no competing interests. Funding This study is funded by the Norwegian Ministry of Defense. The funder had no role in the design of the study, data collection, analysis, or interpretation of the data or writing of the manuscript. Authors' contributions The study design was conceptualized by Kristine Vejrup and Elin Anita Fadum, who also drafted the manuscript and interpreted the results. Hye Jung Choi conducted the analysis and interpretation of transcribed data quality control and the results and participated in manuscript drafting. Leif Åge Strand and Inger Ariansen contributed to interpreting the results. All authors provided feedback on earlier manuscript drafts and collectively approved the final version. 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Lovdata, Oslo. 2005. https://lovdata.no/dokument/SF/forskrift/2005-09-02-1010. Accessed (14 November 2023). Fadum EA, Håberg I, Rønning K, Strand LA, I A. Digitalization of health data from military conscription – a pilot project. Oslo: Norwegian Institute of Public Health2020. Statistics Norway. 10759: Population changes, by sex and rural/urban municipalities (M) (closed series) 1906 - 1968. In: Births. Statistics Norway. 2018. https://www.ssb.no/statbank/table/10759/. Accessed (20 November 2023). Forces] FTNA. Krav til militærtjeneste [Requirements for military service]. https://www.forsvaret.no/krav. Accessed (30 November 2023). Bjerkedal T, Beckstrøm JR, Brevik JI, Skåden K. Høyde, vekt og kroppsmasseindeks ved sesjon for menn født i årene 1967 – 80 [Height, weight, and body mass index at the conscription session for men born in the years 1967 - 1980]. Tidsskr Nor Lægeforen [The Journal of the Norwegian Medical Association]. 2001;121(6):674-7. 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Circulation. 1992;86(2):394-405. doi:10.1161/01.cir.86.2.394 Bjartveit K, Foss OP, Gjervig T. The cardiovascular disease study in Norwegian counties. The results from first screening. Acta Med Scand Suppl. 1983;675:1-184. FHI [Norweigan Institute of Public Health]. Europeisk kortliste for dødsårsaker (COD-SL-2012) [European short list of causes of death (COD-SL-2012)]. Unknown. https://www.fhi.no/globalassets/dokumenterfiler/helseregistre/dar/europeisk-kortliste-for-dodsarsaker--norsk-utvidelse-2012.pdf. Accessed (14 November 2023). European Commission. Health statistics - Atlas on mortality in the European Union: 2009 edition. Luxembourg: Office for Official Publications of the European Communities. 2009. Falkstedt D, Koupil I, Hemmingsson T. Blood pressure in late adolescence and early incidence of coronary heart disease and stroke in the Swedish 1969 conscription cohort. J Hypertens. 2008;26(7):1313-20. doi:10.1097/HJH.0b013e3282ffb17e Hemmingsson T, Melin B, Allebeck P, Lundberg I. The association between cognitive ability measured at ages 18-20 and mortality during 30 years of follow-up--a prospective observational study among Swedish males born 1949-51. Int J Epidemiol. 2006;35(3):665-70. doi:10.1093/ije/dyi321 Bjerkedal T, Brevik JI. Geografiske variasjoner i kroppsmasseindeks målt ved sesjon for menn født i Norge 1967–80 [Geographical variations in body mass index measured by session for men born in Norway 1967–80]. Tidsskr Nor Lægeforen [The Journal of the Norwegian Medical Association]. 2001;121:3505–8. Bore RR. Norske rekrutter har skutt i været [Norwegian recruits have skyrocketed]. Kongsvinger: Statistisk sentralbyå [Statistics Norway]. 2007. Ludvigsson JF, Berglind D, Sundquist K, Sundström J, Tynelius P, Neovius M. The Swedish military conscription register: opportunities for its use in medical research. European Journal of Epidemiology. 2022;37(7):767-77. doi:10.1007/s10654-022-00887-0 Christensen GT, Molbo D, Ängquist LH, et al. Cohort Profile: The Danish Conscription Database(DCD): A cohort of 728 160 men born from 1939 through 1959. International Journal of Epidemiology. 2014;44(2):432-40. doi:10.1093/ije/dyu114 Rietz H, Pennlert J, Nordström P, Brunström M. Blood Pressure Level in Late Adolescence and Risk for Cardiovascular Events : A Cohort Study. Ann Intern Med. 2023;176(10):1289-98. doi:10.7326/m23-0112 Kjøllesdal MKR, Ariansen I, Næss Ø E. Early adulthood weight, subsequent midlife weight change and risk of cardiovascular disease mortality: an analysis of Norwegian cardiovascular surveys. Int J Obes (Lond). 2020;44(2):399-408. doi:10.1038/s41366-019-0467-0 Sundström J, Neovius M, Tynelius P, Rasmussen F. Association of blood pressure in late adolescence with subsequent mortality: cohort study of Swedish male conscripts. Bmj. 2011;342:d643. doi:10.1136/bmj.d643 Hemmingsson T, Melin B, Allebeck P, Lundberg I. Cognitive ability in adolescence and mortality in middle age: a prospective life course study. J Epidemiol Community Health. 2009;63(9):697-702. doi:10.1136/jech.2008.079160 Additional Declarations No competing interests reported. Supplementary Files Supplementary1950digitizedcohort.docx Cite Share Download PDF Status: Under Review Version 1 posted Editor assigned by journal 05 Apr, 2024 Submission checks completed at journal 05 Apr, 2024 First submitted to journal 05 Apr, 2024 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4221664","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":287835312,"identity":"239eec8c-353b-4983-8489-10f2bc1b3efc","order_by":0,"name":"Kristine Vejrup","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAArElEQVRIiWNgGAWjYBACCSA2AGI5BmbmBtK0GDMwM5KgBQQSGxiI1SI5I/lAcWXbnfS17YwNzAUVRGiRlkhLMDzb9ix322GglhlniNAix3PGwLCx7TBEC28bUVrOfwBpSTcjWos0ew8DSEsC8Vok29sMDBvOPTMEOewwDzF+kTjM/MywoeyOvNn5wwcf8xATYkDABozKA2DWAeI0MDAwPyBB8SgYBaNgFIxEAACF1jYC8/Tn4AAAAABJRU5ErkJggg==","orcid":"","institution":"The Norwegian Armed Forces Joint Medical Services","correspondingAuthor":true,"prefix":"","firstName":"Kristine","middleName":"","lastName":"Vejrup","suffix":""},{"id":287835313,"identity":"4dc10473-7801-4007-ac6b-4261afc182d9","order_by":1,"name":"Hye Jung Choi","email":"","orcid":"","institution":"University of Oslo","correspondingAuthor":false,"prefix":"","firstName":"Hye","middleName":"Jung","lastName":"Choi","suffix":""},{"id":287835314,"identity":"ad944178-b201-47bb-8c4d-6ff5b2232e2a","order_by":2,"name":"Leif Åge Strand","email":"","orcid":"","institution":"The Norwegian Armed Forces Joint Medical Services","correspondingAuthor":false,"prefix":"","firstName":"Leif","middleName":"Åge","lastName":"Strand","suffix":""},{"id":287835315,"identity":"89cd23bf-ccb3-43e0-a009-ce653a53c7c4","order_by":3,"name":"Inger Ariansen","email":"","orcid":"","institution":"Norwegian Institute of Public Health","correspondingAuthor":false,"prefix":"","firstName":"Inger","middleName":"","lastName":"Ariansen","suffix":""},{"id":287835316,"identity":"afd36c22-6fd6-4259-a589-004838827707","order_by":4,"name":"Elin Anita Fadum","email":"","orcid":"","institution":"The Norwegian Armed Forces Joint Medical Services","correspondingAuthor":false,"prefix":"","firstName":"Elin","middleName":"Anita","lastName":"Fadum","suffix":""}],"badges":[],"createdAt":"2024-04-05 08:35:04","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4221664/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4221664/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":54432620,"identity":"4969ff1f-d7ee-4d16-bfa6-581330663010","added_by":"auto","created_at":"2024-04-10 11:56:25","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":31998,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of the number of Norwegian men born in 1950, their attendance on Conscription board health examinations (CBHEs) and first day in service health examinations (FDHEs), and available data stored at the National Archives of Norway.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-4221664/v1/713f59cfce0e6c73ad89ef4a.png"},{"id":54432622,"identity":"23034dd0-361d-44e1-ad49-9d190a86e37d","added_by":"auto","created_at":"2024-04-10 11:56:25","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":9517493,"visible":true,"origin":"","legend":"\u003cp\u003eMap of Norway showing the sites of the Military Conscription Board Health Examinations in 1968-69.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-4221664/v1/1b83f3b091cd99cec8ffc320.png"},{"id":54432623,"identity":"d83d7281-2272-4d0e-88e1-b826583efa2f","added_by":"auto","created_at":"2024-04-10 11:56:25","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":90066,"visible":true,"origin":"","legend":"\u003cp\u003eSystolic (SBP) and diastolic (DBP) blood pressure (mm Hg) at two time points between the conscription board health examinations (CBHE) and the first day in military service (FDHE). Histograms and box plots of frequencies, including normal curves of the distributions.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-4221664/v1/b7697844042ece00c55f37c2.png"},{"id":54432621,"identity":"f656f981-3b42-4ede-9b8f-7f82bedd8915","added_by":"auto","created_at":"2024-04-10 11:56:25","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":45480,"visible":true,"origin":"","legend":"\u003cp\u003eHeart rate (beats/min) at two time points between the conscription board health examinations (CBHE) and the first day in military service (FDHE). Histograms and box plots of frequencies, including normal curves of the distributions\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-4221664/v1/96e5730f09dde7488cf3b395.png"},{"id":54432871,"identity":"c197b875-acb7-4780-a158-f7d2bee76af6","added_by":"auto","created_at":"2024-04-10 12:04:26","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1011291,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4221664/v1/fd472bbb-156c-4e3e-85b1-3ecf408ad7f8.pdf"},{"id":54432626,"identity":"debd3a7e-58bb-4fe6-a7e0-b48a49070ba5","added_by":"auto","created_at":"2024-04-10 11:56:25","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":7846753,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementary1950digitizedcohort.docx","url":"https://assets-eu.researchsquare.com/files/rs-4221664/v1/68af5db73ee6c2a04ed38ee7.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Digitizing Paper-based Military health records from Norwegian males born in 1950 – assessments of data quality and applicability in research","fulltext":[{"header":"Highlights","content":"\u003cul\u003e\n \u003cli\u003eDigitizing lost or omitted information can enhance an existing registry.\u003c/li\u003e\n \u003cli\u003eThe digitization of military archives can open possibilities for future research.\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"Summary table","content":"\u003cp\u003e\u003cem\u003eWhat was already known about the topic\u003c/em\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eThe Norwegian Armed Forces Health Registry (NAFHR)\u0026nbsp;serves as a national health registry for data collected during military service, but information on Norwegian males born before or in the 1950s is missing.\u003c/li\u003e\n \u003cli\u003eThrough collaboration with the National Archives of Norway, we discovered paper-based military archives containing health information for cohorts with insufficient data.\u003c/li\u003e\n \u003cli\u003eThere were uncertainties regarding the preservation of these archives for digital reproduction and the accuracy of clinical measurements for research purposes.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cem\u003eWhat this study added to our knowledge\u003c/em\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eQuality control and comparison with data from the NAFHR and national health surveys revealed good compliance and readability of the transcribed material.\u003c/li\u003e\n \u003cli\u003eThis digitization enriches the existing registry (NAFHR in our case), thereby expanding possibilities for future research.\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"1. INTRODUCTION","content":"\u003cp\u003eIn Norway, conscription to military service is a guiding principle in the social contract between the country's citizens and the state. Eligible men and women must attend a military board health examination to determine their fitness for duty (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). The conscription board health examination (CBHE) prior to service consisted of clinical examinations and tests of physical and mental health, following standard guidelines of the Norwegian Armed Forces Joint Medical Services. These military medical screening procedures were established in the 1950s and have not changed much over time (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe data collected at the CBHE are stored in the Norwegian Armed Forces Health Registry (NAFHR). This national health registry was established in 2005 and is used for monitoring the health status of military personnel through their service (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Data from the Armed Forces Personnel Database, the Military Electronic Medical Records System, and the Norwegian Cause of Death Registry were regularly entered into the NAFHR. The data collected in the registry span over 5 decades with nearly complete national coverage.\u003c/p\u003e \u003cp\u003eHowever, most military personnel born before 1950 are not registered in the NAFHR. Furthermore, information on height, weight and general cognitive ability is missing for up to 30% of the registered men born in 1950, despite being the first cohort for which such information was registered in the NAFHR. The data loss can, at least partly, be explained by the Armed Forces\u0026rsquo; archive procedures. A military electronic personnel database was adopted in 1992; before that time, military records were paper-based and kept within personnel files that were handed over to the National Archives of Norway when the person turned 70 years old. Therefore, the electronic database does not encompass the entire older conscript population, and some of the most detailed clinical data are still stored in papers at the National Archives only. A search at the National Archives showed that paper-based military archives contained health information for at least 50\u0026ndash;60% of Norwegian men born between 1941 and 1957 and that military service cards were tagged with an 11-digit personal identification number unique to every Norwegian individual (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). This discovery presented an opportunity to expand and update the electronically searchable information in the NAFHR by digitizing the military archives. However, the consistency and accuracy of the data were unknown.\u003c/p\u003e \u003cp\u003eThis paper aims to present military health data that have been retrieved and transcribed from archived personnel files belonging to Norwegian men born in 1950\u0026mdash;the first birth cohort registered in the NAFHR\u0026mdash;to evaluate the quality of the data and suggest opportunities for research.\u003c/p\u003e"},{"header":"2. MATERIALS AND METHODS","content":"\u003cp\u003e \u003cem\u003e2.1 Military personnel files belonging to Norwegian men born in 1950 stored in the National Archives (98 words)\u003c/em\u003e \u003c/p\u003e \u003cp\u003eIn 1950, 32 203 boys were born in Norway (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). The Norwegian conscription law obliged them all to attend a CBHE when they reached the age of 18\u0026ndash;19 years to determine their fitness for military service (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). Approximately 6\u0026ndash;7% of the birth cohorts were exempted before the CBHE, mainly because of death, emigration, disabling diseases, or crime (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). The National Archives in Oslo stored military service records from 17 324 Norwegian men born in 1950 [Figure \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e], hereinafter referred to as \u0026ldquo;the digitized 1950 cohort\u0026rdquo;.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Examinations conducted at the conscription board and on the first day of service\u003c/h2\u003e \u003cp\u003eSince 2010, CBHEs have been conducted at ten regional centers that are specially equipped for military medical examinations. However, in 1968-69, CBHEs were conducted locally in municipalities across the country [Figure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e]. For our review, we categorized the military conscription sites into 19 groups that corresponded with the former Norwegian county classification (1946\u0026ndash;2018) [9] [Figure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, STable 1]. The local police districts or assembly halls were venues for conscription summoning, while military doctor teams travelled around the country with medical equipment for measuring. The CBHEs and first day-in-service health examinations (FDHEs) were performed according to instructions provided by the Armed Forces Joint Medical Services (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eHeight and weight were measured to the nearest centimeter (cm) and kilogram (kg), respectively. Systolic and diastolic blood pressure (SBP and DBP) were measured in mm Hg on the right upper arm after 5 minutes of seated rest using an appropriately sized cuff and manual sphygmomanometer. The resting heart rate was measured by pulse palpation as beats per minute. Furthermore, the physical health assessment consisted of a clinical interview, a review of the candidate\u0026rsquo;s personal statements of health, and any medical documentation of disease. A test for cognitive ability, introduced in 1954 and referred to as \u0026ldquo;general ability\u0026rdquo; (GA) in the CBHE, consisted of three different subtests: numeracy, word similarity, and figure. The Stanine scores of GA (short for \u0026ldquo;Standard Nine\u0026rdquo;) range from 1 (worst) to 9 (best). A more detailed description of the tests and scores can be found elsewhere (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Digitized information of the 1950 cohort\u003c/h2\u003e \u003cp\u003eIn the Supplement, there are examples of medical documents that were commonly preserved in the personnel files and digitized [SFigure 1\u0026ndash;4]. Among a great variety of conserved military medical forms, we chose to review and transcribe selected information from the conscripts\u0026rsquo; structured medical journal [SFigure 1] and the GA test [SFigure 2]. In cases where both the medical journal and the GA test were missing, we digitized this information (if available) from the military service records [SFigure 3]. Self-declaration of health [SFigure 4] included information about health conditions in childhood and the family [STable 2]. The following information was selected for transcription: place and date of the military medical examination, height (cm), weight (kg), SBP and DBP, heart rate per min, and GA-scores (stanine score and the scores from each of the three subtests).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Transcription process\u003c/h2\u003e \u003cp\u003eThe data were manually transcribed into an Access database according to a codebook developed in the pilot phase of the project. Seven employees participated in the transcription, and the employees were all given training by the same personnel and used the same codebook and database. In the quality control of the transcription process, the 11-digit personal identification number was linked to the Norwegian Population Registry to identify and correct erroneous registrations. The transcribing staff regularly reviewed the transcribed data for any outlier values and corrected them.\u003c/p\u003e \u003cp\u003eOnce the transcribing task was over, members of the project group who had not been involved in transcribing rereviewed the data for unrealistic values/records and verified the accuracy of these values by comparing them with the original documents. Numeric values were checked for any extreme values, while nonnumeric values, such as dates, were checked for errors. A total of 103 transcribed cases with outlying numbers and unrealistic information were identified. The information in the personnel files was reviewed and corrected for 51 cases. The remaining 52 cases were found to have been transcribed correctly, although those numbers were unrealistic. These were attributed to errors made by the doctors, illegible handwriting, or poor quality of the original documents.\u003c/p\u003e \u003cp\u003eTo assess the reliability of our transcribing process, we conducted an intra-investigator reproducibility test to determine whether the same records would be transcribed differently by different staff. We randomly selected 100 men from the cohort and compared the transcriptions of two different staff members. Out of the 1800 total transcribed values, only 38 (2.1%) deviated between the two staff members; among these, 25 deviating records were due to mistakes (n\u0026thinsp;=\u0026thinsp;22) and different transcribing due to individual interpretation of records (n\u0026thinsp;=\u0026thinsp;3). The remaining discrepant records were attributed to illegible handwriting, doctors\u0026rsquo; mistakes, and poor document conditions.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. RESULTS","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Quality control of the transcribed data\u003c/h2\u003e \u003cp\u003eOf the 17 324 men who participated in CBHE, 85% had recorded weight data, and 75% had recorded heart rate data [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e]. Unfortunately, major conscription sites in western Norway did not record weight during this period. In total, 15 790 men (91%) also had health records at FDHE [Figure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e]. Heart rate at the FDHE was rarely recorded (missing n\u0026thinsp;=\u0026thinsp;12 076), as the doctors left this section empty or wrote \"RM\" (regular) in most cases.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\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 on Norwegian men born in 1950 based on information transcribed from 17 324 military health records at the National Archives of Norway.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNumber of men\u003c/p\u003e \u003cp\u003e(% of 17 324)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMin\u0026ndash;Max\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMean (SD)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMedian\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSkewness\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eKurtosis\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"7\" nameend=\"c7\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eConscription board health examination (CBHE)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePlace\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16 269 (94)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c7\" namest=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYear\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16 574 (96)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1966\u0026ndash;1976\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1969 (0.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1969\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeight, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17 028 (98)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e151\u0026ndash;205\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e178.8 (6.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e179\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-0.1\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.1\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWeight, kg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 718 (85)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e41\u0026ndash;123\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e68.6 (8.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.7\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.7\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeart rate, beats per minute\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 988 (75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40\u0026ndash;120\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e72.1 (8.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.7\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.1\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSBP, mm Hg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16 040 (93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e85\u0026ndash;200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e127.6 (11.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e125\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.8\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.5\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDBP, mm Hg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16 046 (93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u0026ndash;120\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e77.2 (8.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-0.3\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.5\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGAstanine score\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15 885 (92)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u0026ndash;9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.9 (1.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-0.2\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.5\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e- Numeric test\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 021 (81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u0026ndash;30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e18.8 (5.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-0.5\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.6\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e- Word similarity test\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 018 (81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u0026ndash;36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25.7 (4.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-1.0\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.2\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e- Figure test\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 034 (81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u0026ndash;54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e31.9 (10.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-0.2\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.2\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFirst day in service health examination (FDHE)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYear\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15 790 (91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1967\u0026ndash;1980\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1970 (1.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1970\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeight, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11 082 (64)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e152\u0026ndash;205\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e178.9 (6.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e179\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWeight, kg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13 054 (75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e46\u0026ndash;124\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e70.6 (9.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.8\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.8\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeart rate, beats per minute\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3714 (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e48\u0026ndash;138\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e77.3 (11.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.1\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.1\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSBP, mm Hg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11 951 (69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e80\u0026ndash;230\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e133.3 (13.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e130\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.7\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.1\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDBP, mm Hg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11 989 (69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e35\u0026ndash;130\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e80.4 (9.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.2\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.8\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"7\" nameend=\"c7\" namest=\"c1\"\u003e \u003cp\u003e\u003csup\u003e*\u003c/sup\u003e indicates a p value\u0026thinsp;\u0026lt;\u0026thinsp;.05 in the skewness and kurtosis test for normality.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eWhen examining the records of the conscripts for which there were significant differences between CBHE and FDHE, 312 discrepant cases were found, and 123 registrations were corrected by reviewing the registrations. The remaining 189 possibly erroneous registrations were attributed to the same reasons as described earlier. During the examination, minor changes in height and weight were found between these two time points, as FDHEs are usually present one year after CBHEs [Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e].\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\u003eComparisons\u003csup\u003e*\u003c/sup\u003e of height and weight records measured at the conscription board health examinations (CBHE) one year prior to military service and on the first day in military service (first day health examinations, FDHE) transcribed from military health records at the National Archives of Norway.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNumber of men with discrepant records between CBHE and FDHE\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMean difference (SD)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMedian difference\u003c/p\u003e \u003cp\u003e(10th to 90th percentile)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMin to Max difference\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDays from CBHE to FDHE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15 647\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e615 (456)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e495 (217 to 1156)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-197 to 4148\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference in height (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 941\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.1 (1.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0 (-2 to 2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-20 to 22\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference in weight (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11 254\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.2 (3.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.8 (-2 to 7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-19 to 30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003e\u003csup\u003e*\u003c/sup\u003e Differences were computed by subtracting the CBHE values from the FDHE values\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eWe cross-referenced the transcribed height, weight, and GA-staninescores with the records that were already available in the NAFHR. Among the 17 324 conscripts, 16 551 had CBHE heights recorded in the NAFHR, but only 705 had CBHE weights recorded in the NAFHR [Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e]. This comparison enabled us to uncover disparities between the two databases, expecting no differences between the transcribed records and measurements registered in NAFHR. Overall, the number of discrepancies in the records between the two databases was low, except for weight records. This discrepancy arose because the weight records of the NAFHRs included decimals, which differed from the format of the transcribed weight records.\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\u003eHeight, weight, and general ability (GA-staninescores) transcribed from military health records at the National Archives of Norway and compared to* registrations in the Norwegian Armed Forces Health Registry (NAFHR).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNumber of men with comparable registration records\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNumber (%\u003csup\u003e\u0026sect;\u003c/sup\u003e) of men with discrepant registrations\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMean discrepancies (SD)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMedian\u003c/p\u003e \u003cp\u003e(10th to 90th percentile)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eMin to Max discrepancy\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeight (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16 551\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e610 (3.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0 (0.85)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0 (0 to 0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-30 to 20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWeight (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e705\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e278 (39.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.85 (3.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0 (-0.5 to 4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-20 to 33\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGA-stanine score\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 809\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e145 (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0 (0.23)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0 (0 to 0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e-5 to 6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003e\u003csup\u003e*\u003c/sup\u003eDiscrepancies were computed by subtracting the transcribed values from the values registered in the NAFHR.\u003c/p\u003e \u003cp\u003e\u003csup\u003e\u0026sect;\u003c/sup\u003eThe number of men with discrepancies was divided by the number of men with comparable registration records in a measurement variable.\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 \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Descriptive statistics\u003c/h2\u003e \u003cp\u003eTo explore the variance of the transcribed data and assess whether the records were accurate enough for research purposes, we used descriptive statistics of the digitized 1950 cohort on height, weight, SBP, DPB, heart rate, and GA-stanine score [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e]. Overall, the mean blood pressure and heart rate were greater at FDHE than at CBHE. The heart rate, SBP, and DBP at CBHE clustered around some specific values. For example, 43% of the total observations in CBHE-DBP had a value of 80 mm Hg, and 32% of the CBHE-SBP was 120 mm Hg [Figure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e]. Similarly, 23% of the CBHE heart rate patients had a heart rate of 72 bpm [Figure \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e]. The mean GA-stanine score for the cohort was 5.9 points, with an SD of 1.7.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe transcribed height, weight, and blood pressure data were compared to the means, SDs, and medians of similar published data from surveys conducted on young men in Scandinavia (\u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). The means and SDs of transcribed height and weight records were comparable to those of the cohorts in these surveys. We observed smaller SDs for SBP, DBP, and heart rate at the CBHE than at the FDHE and population surveys, while each of the means were comparable to those of other health surveys [Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eOverview of information transcribed from military health records at the National Archives of Norway and registrations in the Norwegian Armed Forces Health Registry (NAFHR) and population health surveys on young men in Norway.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"11\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSource\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eDigitized personnel files stored\u003c/p\u003e \u003cp\u003eat the National Archives\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eThe Norwegian Armed Forces Health Registry\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c11\" namest=\"c8\"\u003e \u003cp\u003ePopulation health surveys\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRegion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eNational\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eNational\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003eTroms\u0026oslash; municipality\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003eFinnmark\u003csup\u003eF\u003c/sup\u003e, Sogn og Fjordane\u003csup\u003eSF\u003c/sup\u003e and Oppland\u003csup\u003eO\u003c/sup\u003e counties\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExamination year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003e1969 (range 1966\u0026ndash;1976)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e1969 (range 1966\u0026ndash;1990)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1974(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e1986-87(\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003e1974\u0026ndash;78(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBirth cohort\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003e1950\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003e1950\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1950\u0026ndash;1954\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e1957\u0026ndash;1966\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003e1950\u0026ndash;1956\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParticipants\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e\u003csup\u003e1\u003c/sup\u003eCBHE n\u0026thinsp;=\u0026thinsp;17 324\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003e\u003csup\u003e2\u003c/sup\u003eFDHE n\u0026thinsp;=\u0026thinsp;15 790\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;25 770\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;502\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;2380\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;449\u003csup\u003eF\u003c/sup\u003e, n\u0026thinsp;=\u0026thinsp;226\u003csup\u003eSF\u003c/sup\u003e, n\u0026thinsp;=\u0026thinsp;412\u003csup\u003eO\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003csup\u003e3\u003c/sup\u003eMean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003csup\u003e4\u003c/sup\u003eMedian\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003csup\u003e3\u003c/sup\u003eMean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003csup\u003e4\u003c/sup\u003eMedian\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003csup\u003e3\u003c/sup\u003eMean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003csup\u003e4\u003c/sup\u003eMedian\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003csup\u003e3\u003c/sup\u003eMean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003csup\u003e4\u003c/sup\u003eMedian\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e\u003csup\u003e3\u003c/sup\u003eMean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u003csup\u003e4\u003c/sup\u003eMedian\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge/Age range\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18.9\u003c/p\u003e \u003cp\u003e(0.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18.7\u003c/p\u003e \u003cp\u003e[18.4\u0026ndash;19.3]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20.5\u003c/p\u003e \u003cp\u003e(1.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e20.2\u003c/p\u003e \u003cp\u003e[19.4\u0026ndash;22.1]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e19.2\u003c/p\u003e \u003cp\u003e(2.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18.6\u003c/p\u003e \u003cp\u003e[18.1\u0026ndash;20.4]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e20\u0026ndash;24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e20\u0026ndash;29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e20\u0026ndash;24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e20\u0026ndash;24\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeight (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e178.8\u003c/p\u003e \u003cp\u003e(6.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e179\u003c/p\u003e \u003cp\u003e[171\u0026ndash;187]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e178.9\u003c/p\u003e \u003cp\u003e(6.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e179\u003c/p\u003e \u003cp\u003e[171\u0026ndash;187]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e178.6\u003c/p\u003e \u003cp\u003e(6.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e179\u003c/p\u003e \u003cp\u003e[170\u0026ndash;187]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e174.1 (6.9)\u003csup\u003eF\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e178.4 (5.8)\u003csup\u003eSF\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e178.6 (5.4)\u003csup\u003eO\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWeight (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e68.6\u003c/p\u003e \u003cp\u003e(8.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e68\u003c/p\u003e \u003cp\u003e[59\u0026ndash;79]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e70.6\u003c/p\u003e \u003cp\u003e(9.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e70\u003c/p\u003e \u003cp\u003e[60\u0026ndash;82]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e70.9\u003c/p\u003e \u003cp\u003e(9.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e70\u003c/p\u003e \u003cp\u003e[60\u0026ndash; 83]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e69.5 (8.2)\u003csup\u003eF\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e71.7 (8.9)\u003csup\u003eSF\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e74.1 (9.9)\u003csup\u003eO\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGA-staninescore\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.9\u003c/p\u003e \u003cp\u003e(1.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6\u003c/p\u003e \u003cp\u003e[4\u0026ndash;9]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.8\u003c/p\u003e \u003cp\u003e(1.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6\u003c/p\u003e \u003cp\u003e[3\u0026ndash;8]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSBP (mm HG)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e127.6 (11.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e125\u003c/p\u003e \u003cp\u003e[115\u0026ndash;140]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e133.3\u003c/p\u003e \u003cp\u003e(13.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e130\u003c/p\u003e \u003cp\u003e[120\u0026ndash;150]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e124.5\u003c/p\u003e \u003cp\u003e(13.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e133.9 (13.0)\u003csup\u003eF\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e132.9 (14.0)\u003csup\u003eSF\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e134.3 (13.3)\u003csup\u003eO\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e132 (118\u0026ndash;150)\u003csup\u003eF\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e132 (114\u0026ndash;150)\u003csup\u003eSF\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e134 (120\u0026ndash;152)\u003csup\u003eO\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDBP (mm Hg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e77.2 (8.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e80\u003c/p\u003e \u003cp\u003e[60\u0026ndash;95]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e80.4\u003c/p\u003e \u003cp\u003e(9.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e80\u003c/p\u003e \u003cp\u003e[70\u0026ndash;90]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e73.8\u003c/p\u003e \u003cp\u003e(11.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e75.0 (10.0)\u003csup\u003eF\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e74.7 (10.8)\u003csup\u003eSF\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e75.1 (10.3)\u003csup\u003eO\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e76 (62\u0026ndash;88)\u003csup\u003eF,SF,O\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeart rate (bpm\u003csup\u003e3\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e72.1 (8.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e72\u003c/p\u003e \u003cp\u003e[60\u0026ndash;80]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e77.3\u003c/p\u003e \u003cp\u003e(11.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e76\u003c/p\u003e \u003cp\u003e[64\u0026ndash;92]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e71.0 (12.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"11\" nameend=\"c11\" namest=\"c1\"\u003e \u003cp\u003e\u003csup\u003e1\u003c/sup\u003eCBHE=Conscription board health examination \u003csup\u003e2\u003c/sup\u003eHealth examinations conducted at the first day in military service (first day health examinations FDHE)\u003c/p\u003e \u003cp\u003e\u003csup\u003e3\u003c/sup\u003eMean represents the mean (standard deviation), and \u003csup\u003e4\u003c/sup\u003eMediancorresponds to the median [10th \u0026minus;\u0026thinsp;90th percentile]. \u003csup\u003e5\u003c/sup\u003eBeats per minute.\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 \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Assessing transcribed data in statistical models for cardiovascular disease mortality\u003c/h2\u003e \u003cp\u003eWe performed a series of statistical tests to investigate features of the digitized 1950 cohort related to cardiovascular disease (CVD) mortality. By linking data on the underlying cause of death registered in the Norwegian Cause of Death Registry, we included deaths that occurred from the year of CBHE to the end of 2021. The EU shortlist for Causes of Death, which ensures comparability over time, was used to identify the underlying cause of death, and CVD deaths were defined using codes 44\u0026ndash;50 from the list (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eFirst, we assessed whether the proportion of deaths from CVD among all deaths differed between two samples: the digitized 1950 cohort (n\u0026thinsp;=\u0026thinsp;17 324) and all the individuals born in 1950 who were registered in the NAFHR (n\u0026thinsp;=\u0026thinsp;25 770). Among the digitized cohort, 23.6% died from CVD, whereas 21.6% of those born in the same year from NAFHR did, resulting in a 2% difference in the proportions (p\u0026thinsp;=\u0026thinsp;0.03) [STable 3].\u003c/p\u003e \u003cp\u003eNext, we used two multivariable logistic regression models to examine whether some of the transcribed information that could be considered CVD risk factors would demonstrate the expected predictive relationships with CVD mortality. Four independent variables were selected based on known associations with CVD (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e): higher risk of CVD mortality with lower GA-stanine scores (continuous), higher body mass index (BMI) (continuous), and higher SBP and DBP (groups relative to the normal range). SEP and DBP were categorized into four groups based on a Swedish study of male conscripts born between 1949 and 1951 (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e) [STable 4]. The CBHE model involved 11 581 conscripts with complete information on the four selected variables. The FDHE model included 7367 conscripts selected for military service, providing the aforementioned information during their FDHE and a GAstaninescore from the CBHE.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eOdds ratio (95% confidence intervals) for CVD mortality (from the year of CBHE until 2021) based on information transcribed from military health records stored at the National Archives of Norway\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\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eOdds ratio (95% CI)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eCVD risk factors\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCBHE (n\u0026thinsp;=\u0026thinsp;11 581)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eFDHE (n\u0026thinsp;=\u0026thinsp;7367)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eGA stanine score per 1 unit\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.86 (0.82\u0026ndash;0.90)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.86 (0.80\u0026ndash;0.91)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eBMI per 1 kg/m\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.11 (1.07\u0026ndash;1.15)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.10 (1.06\u0026ndash;1.15)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eSBP, mm Hg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;115\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.24 (0.86\u0026ndash;1.77)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.06 (0.57\u0026ndash;1.97)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e115 to \u0026lt;\u0026thinsp;125\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eref\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eref\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e125 to \u0026lt;\u0026thinsp;135\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.83 (0.67\u0026ndash;1.04)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.11 (0.80\u0026ndash;1.55)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;135\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.86 (0.68\u0026ndash;1.09)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.04 (0.75\u0026ndash;1.44)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eDBP, mm Hg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.76 (0.52\u0026ndash;1.11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.28 (0.09\u0026ndash;0.90)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e65 to \u0026lt;\u0026thinsp;75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eref\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eref\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e75 to \u0026lt;\u0026thinsp;85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.82 (0.66\u0026ndash;1.03)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.96 (0.69\u0026ndash;1.33)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.10 (0.84\u0026ndash;1.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.27 (0.90\u0026ndash;1.79)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003e\u003csup\u003e*\u003c/sup\u003e: p value\u0026thinsp;\u0026lt;\u0026thinsp;0.05\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe associations between the GA-stanine score and CVD mortality, as well as between BMI and CVD mortality, remained consistent between the two models [Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e]. This indicated that those with a higher GA-stanine score or lower BMI were at lower risk of CVD mortality. Regarding the association between blood pressure and CVD mortality, only the lowest DBP group in the FDHE model demonstrated a significantly lower risk of CVD mortality (OR\u0026thinsp;=\u0026thinsp;0.28, 95% CI: 0.09\u0026ndash;0.90). While most of the numeric effect estimates of the higher SBP groups in the CBHE model implied a \u003cem\u003elower\u003c/em\u003e risk of CVD mortality compared to the reference, higher SBP groups in the FDHE implied \u003cem\u003ehigher\u003c/em\u003e CVD mortality. For DBP, the numeric OR effect estimates had a similar direction in the CBHE and FDHE models.\u003c/p\u003e \u003c/div\u003e"},{"header":"4. DISCUSSION","content":"\u003cp\u003eThis paper describes the digitization of military paper-based archives covering approximately 60% of all Norwegian men born in 1950. We assume that the cohort represents the healthy and normally skilled proportion of men born in 1950. This assumption was strengthened by the finding of normally distributed health data that were comparable to the data found in population health surveys in the same age group and by the fact that few men died before 2021. Approximately 6.4% of males in the 1950-born cohort did not attend CBHE and were not included in the cohort. The files belonging to those who died or were deemed unfit for further military service after having conducted basic military training were stored in archives that were not subjected to our review. The same archive procedure was also applied to men who became officers or military police or who refused military service for ethical reasons. An extended review of more archives could further increase the generalizability of the digitized cohort. Unfortunately, as there has been no absolute safeguarding of the military archives, we must consider that some of the personnel files and some of the documents stored within the files may have been lost.\u003c/p\u003e \u003cp\u003eOverall, we found that the information we selected for digitization was consistently recorded in the military health records and was accurately transcribed. This indicates that these records were well preserved and easily readable. Missing records from FDHE should be considered a limitation, as measurements from two separate times would have provided an opportunity to assess the quality of the measurements as well as determine true changes in health between two time points. We speculate that doctors may only have recorded FDHE information if it differed from the CBHE measures.\u003c/p\u003e \u003cp\u003eIn approximately 1968-69, when the men in the digitized cohort were summoned to CBHE, the medical examination procedures were much the same as they are today, but the setting and locations differed. Currently, there are 10 stationary locations for conscript examinations in Norway; however, in the archived material, we registered 141 different locations across the country. While some of the locations were stationary and located in military facilities, the majority operated on a temporary basis. This arrangement may have introduced some variability since military doctors had to travel with measurement equipment to different locations, and a larger number of medical staff were performing measurements. Nevertheless, the regional differences in the clinical measurements (not presented) were consistent with known differences in height and weight observed in other studies (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTo determine whether the data were accurate enough for research purposes, we used a range of methods, including examining inconsistencies within the transcribed and already registered data, comparing data with results in similar populations, and conducting statistical analyses. The digitized 1950 cohort data demonstrated high reliability and validity. This was supported by the minimal discrepancies between measures recorded at two different time points for military health examinations for the same individuals, the consistency with existing NAFHR records, and the predictive accuracy of CVD mortality.\u003c/p\u003e \u003cp\u003eSeveral Nordic studies have been carried out to investigate conscription databases and utilize conscription records for epidemiological studies (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan additionalcitationids=\"CR21 CR22 CR23 CR24\" citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e). Despite the differences in the aims of the studies and the inclusion criteria, it is worth noting that the findings from our statistical analysis aligned with the outcomes of these prior studies (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e). However, our findings did not show the expected consistent association between higher SBP and DBP levels and CVD mortality and differed from previous studies that revealed the influence of both SBP and DBP on CVD mortality (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eWe noticed that the process of measuring and recording blood pressure in military examination settings might have been imprecise. Clinicians might have been instructed to round up their records or might have had preferences for specific numbers. Notably, in measurements taken at CBHE, as depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, the clustering of SBP and DBP values around certain numbers suggests rounding to the nearest 5 or 10 mmHg, potentially leading to an underestimation of associations (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e). This may indicate that the measurements of SBP and heart rate at the CBHE examination are of somewhat lower quality than the measurements collected on the FDHE or in a health survey. Differences in the competence requirements and procedures between the military health personnel at CBHE and FDHE could lead to more imprecise CBHE measurements.\u003c/p\u003e"},{"header":"5. CONCLUSION","content":"\u003cp\u003eThis review included health records stored at the National Archives of Norway from the 1950 male birth cohort of Norway. The assessment of the transcribed material showed conformity with the source documents. The results support that the digitization of military personal files stored at the National Archives of Norway can enhance a national health registry by the inclusion of information that has been lost or was not included in the registry.\u003c/p\u003e \u003cp\u003eThe military personnel files and documents that have been handed over to the National Archives must be considered unique data sources, both in the Norwegian context and in the international context. There is great interest in these data for long-term studies of dementia, cardiovascular diseases, and obesity, among others. The digitization of these data can facilitate more effective communication and research on public health as well as for veteran affairs by linking them to other national health registries and opening possibilities for longitudinal research.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eBMI: Body mass index\u003c/p\u003e\n\u003cp\u003eCBHE: Conscription board health examination\u003c/p\u003e\n\u003cp\u003eCI: Confidence interval\u003c/p\u003e\n\u003cp\u003eCm: Centimeter\u003c/p\u003e\n\u003cp\u003eCVD: \u003cem\u003eCardiovascular disease\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eDBP: Diastolic blood pressure\u003c/p\u003e\n\u003cp\u003eFDHE: First day of service health examination\u003c/p\u003e\n\u003cp\u003eGA: General ability\u003c/p\u003e\n\u003cp\u003eICD: International Classification of Diseases\u003c/p\u003e\n\u003cp\u003ekg: Kilogram\u003c/p\u003e\n\u003cp\u003emm Hg: millimetre of mercury\u003c/p\u003e\n\u003cp\u003eNAFHR: Norwegian Armed Forces Health Registry\u003c/p\u003e\n\u003cp\u003eSBP: systolic blood pressure\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eEthical approval\u003c/h2\u003e\n\u003cp\u003eThis investigation, as a quality control project, was not required to obtain approval from the Regional Committees for Medical and Health Research Ethics (REK). The work is authorized in the Regulations for the Norwegian Armed Forces Health Registry (NAFHR) and is carried out by employees of the NAFHR who are authorized to process the data without the data subjects\u0026apos; consent according to the Health Register Act, regulations, and security manual for the NAFHR.\u003c/p\u003e\n\u003ch2\u003eConsent for publication\u003c/h2\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003ch2\u003eAvailability of data and materials\u003c/h2\u003e\n\u003cp\u003eThe datasets generated and/or analysed during the current study are not publicly available but are available from the NAFHR with necessary approval.\u003c/p\u003e\n\u003ch2\u003eCompeting interests\u003c/h2\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003ch2\u003eFunding\u003c/h2\u003e\n\u003cp\u003eThis study is funded by the Norwegian Ministry of Defense. The funder had no role in the design of the study, data collection, analysis, or interpretation of the data or writing of the manuscript.\u003c/p\u003e\n\u003ch2\u003eAuthors\u0026apos; contributions\u003c/h2\u003e\n\u003cp\u003eThe study design was conceptualized by Kristine Vejrup and Elin Anita Fadum, who also drafted the manuscript and interpreted the results. Hye Jung Choi conducted the analysis and interpretation of transcribed data quality control and the results and participated in manuscript drafting. Leif \u0026Aring;ge Strand and Inger Ariansen contributed to interpreting the results. All authors provided feedback on earlier manuscript drafts and collectively approved the final version.\u003c/p\u003e\n\u003ch2\u003eAcknowledgements\u003c/h2\u003e\n\u003cp\u003eWe extend our sincere gratitude to the National Archives of Norway and our colleagues for their invaluable efforts, cooperation, and contribution to the digitization of the 1950-born cohort in this project.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eForsvarsdepartementet [The Norwegian Ministry of Defence]. Lov om verneplikt og tjeneste i Forsvaret m.m. (forsvarsloven) [Act on conscription and service in the Armed Forces, etc. (Defense Act)]. Lovdata, Oslo. 2022. https://lovdata.no/dokument/NL/lov/2016-08-12-77. Accessed (14 November 2023).\u003c/li\u003e\n\u003cli\u003eFadum EA, Strand LA, Rudvin I, H\u0026aelig;reid ML, Borud EK. The Norwegian Armed Forces Health Registry conscription board health examinations 1968-2018. Scand J Public Health. 2022;50(2):153-60. doi:10.1177/1403494820920412\u003c/li\u003e\n\u003cli\u003eForsvarsdepartementet [The Norwegian Ministry of Defence]. Forskrift om innsamling og behandling av opplysninger i Forsvarets helseregister [Regulations on the collection and processing of information in the Norwegian Armed Forces\u0026apos; health register]. Lovdata, Oslo. 2005. https://lovdata.no/dokument/SF/forskrift/2005-09-02-1010. Accessed (14 November 2023).\u003c/li\u003e\n\u003cli\u003eFadum EA, H\u0026aring;berg I, R\u0026oslash;nning K, Strand LA, I A. Digitalization of health data from military conscription \u0026ndash; a pilot project. Oslo: Norwegian Institute of Public Health2020.\u003c/li\u003e\n\u003cli\u003eStatistics Norway. 10759: Population changes, by sex and rural/urban municipalities (M) (closed series) 1906 - 1968. In: Births. Statistics Norway. 2018. https://www.ssb.no/statbank/table/10759/. 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Circulation. 1992;86(2):394-405. doi:10.1161/01.cir.86.2.394\u003c/li\u003e\n\u003cli\u003eBjartveit K, Foss OP, Gjervig T. The cardiovascular disease study in Norwegian counties. The results from first screening. Acta Med Scand Suppl. 1983;675:1-184.\u003c/li\u003e\n\u003cli\u003eFHI [Norweigan Institute of Public Health]. Europeisk kortliste for d\u0026oslash;ds\u0026aring;rsaker (COD-SL-2012) [European short list of causes of death (COD-SL-2012)]. Unknown. https://www.fhi.no/globalassets/dokumenterfiler/helseregistre/dar/europeisk-kortliste-for-dodsarsaker--norsk-utvidelse-2012.pdf. Accessed (14 November 2023).\u003c/li\u003e\n\u003cli\u003eEuropean Commission. Health statistics - Atlas on mortality in the European Union: 2009 edition. Luxembourg: Office for Official Publications of the European Communities. 2009.\u003c/li\u003e\n\u003cli\u003eFalkstedt D, Koupil I, Hemmingsson T. Blood pressure in late adolescence and early incidence of coronary heart disease and stroke in the Swedish 1969 conscription cohort. J Hypertens. 2008;26(7):1313-20. doi:10.1097/HJH.0b013e3282ffb17e\u003c/li\u003e\n\u003cli\u003eHemmingsson T, Melin B, Allebeck P, Lundberg I. The association between cognitive ability measured at ages 18-20 and mortality during 30 years of follow-up--a prospective observational study among Swedish males born 1949-51. Int J Epidemiol. 2006;35(3):665-70. doi:10.1093/ije/dyi321\u003c/li\u003e\n\u003cli\u003eBjerkedal T, Brevik JI. Geografiske variasjoner i kroppsmasseindeks m\u0026aring;lt ved sesjon for menn f\u0026oslash;dt i Norge 1967\u0026ndash;80 [Geographical variations in body mass index measured by session for men born in Norway 1967\u0026ndash;80]. Tidsskr Nor L\u0026aelig;geforen [The Journal of the Norwegian Medical Association]. 2001;121:3505\u0026ndash;8.\u003c/li\u003e\n\u003cli\u003eBore RR. Norske rekrutter har skutt i v\u0026aelig;ret [Norwegian recruits have skyrocketed]. Kongsvinger: Statistisk sentralby\u0026aring; [Statistics Norway]. 2007.\u003c/li\u003e\n\u003cli\u003eLudvigsson JF, Berglind D, Sundquist K, Sundstr\u0026ouml;m J, Tynelius P, Neovius M. The Swedish military conscription register: opportunities for its use in medical research. European Journal of Epidemiology. 2022;37(7):767-77. doi:10.1007/s10654-022-00887-0\u003c/li\u003e\n\u003cli\u003eChristensen GT, Molbo D, \u0026Auml;ngquist LH, et al. Cohort Profile: The Danish Conscription Database(DCD): A cohort of 728\u0026thinsp;160 men born from 1939 through 1959. International Journal of Epidemiology. 2014;44(2):432-40. doi:10.1093/ije/dyu114\u003c/li\u003e\n\u003cli\u003eRietz H, Pennlert J, Nordstr\u0026ouml;m P, Brunstr\u0026ouml;m M. Blood Pressure Level in Late Adolescence and Risk for Cardiovascular Events : A Cohort Study. Ann Intern Med. 2023;176(10):1289-98. doi:10.7326/m23-0112\u003c/li\u003e\n\u003cli\u003eKj\u0026oslash;llesdal MKR, Ariansen I, N\u0026aelig;ss \u0026Oslash; E. Early adulthood weight, subsequent midlife weight change and risk of cardiovascular disease mortality: an analysis of Norwegian cardiovascular surveys. Int J Obes (Lond). 2020;44(2):399-408. doi:10.1038/s41366-019-0467-0\u003c/li\u003e\n\u003cli\u003eSundstr\u0026ouml;m J, Neovius M, Tynelius P, Rasmussen F. Association of blood pressure in late adolescence with subsequent mortality: cohort study of Swedish male conscripts. Bmj. 2011;342:d643. doi:10.1136/bmj.d643\u003c/li\u003e\n\u003cli\u003eHemmingsson T, Melin B, Allebeck P, Lundberg I. Cognitive ability in adolescence and mortality in middle age: a prospective life course study. J Epidemiol Community Health. 2009;63(9):697-702. doi:10.1136/jech.2008.079160\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-medical-informatics-and-decision-making","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"midm","sideBox":"Learn more about [BMC Medical Informatics and Decision Making](http://bmcmedinformdecismak.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/midm/default.aspx","title":"BMC Medical Informatics and Decision Making","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"The Norwegian Armed Forces Health Registry (NAFHR), Historical archives, Conscription data, Quality control, Military, Digitization","lastPublishedDoi":"10.21203/rs.3.rs-4221664/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4221664/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eAim\u003c/h2\u003e \u003cp\u003eThis study aims to present and assess the quality of military health data extracted from paper-based personnel files of Norwegian men born in 1950, proposing avenues for future research.\u003c/p\u003e\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eArchived military documents contain health information that can enrich the Norwegian Armed Forces Health Registry (NAFHR) with more detailed clinical measurements of older birth cohorts. However, uncertainty exists about the preservation of digital reproduction and the accuracy of clinical measurements for research purposes.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eTo establish an infrastructure at the National Archives of Norway, we digitized military health information covering approximately 60% (n\u0026thinsp;=\u0026thinsp;17 324) of Norwegian men born in 1950. Health records were manually transcribed, and transcribed data were controlled for registered data in the NAFHR. Clinical measures were compared with results from comparable national health surveys, and variations between the conscription board health examinations and the examinations on the first day of service were explored. Transcribed cardiovascular disease (CVD) risk factor data were tested with logistic regression models to assess their predictive ability.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe transcribed data showed good compliance and readability, with overall accurate and valid clinical measurements. While some variations existed between the two examination settings, the measurements generally aligned with the national health survey results. Several of the CVD risk factors in the cohort showed the expected associations with CVD mortality.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThis study highlights the readability and accuracy of digitized military health data, emphasizing its potential for public health and future research through the NAFHR. Further digitization efforts promise enhanced communication and expanded research opportunities.\u003c/p\u003e","manuscriptTitle":"Digitizing Paper-based Military health records from Norwegian males born in 1950 – assessments of data quality and applicability in research","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-04-10 11:56:20","doi":"10.21203/rs.3.rs-4221664/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorAssigned","content":"","date":"2024-04-05T08:52:20+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-04-05T08:51:18+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Medical Informatics and Decision Making","date":"2024-04-05T08:32:52+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-medical-informatics-and-decision-making","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"midm","sideBox":"Learn more about [BMC Medical Informatics and Decision Making](http://bmcmedinformdecismak.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/midm/default.aspx","title":"BMC Medical Informatics and Decision Making","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"d784669e-055f-47fc-8ad9-88572d026dec","owner":[],"postedDate":"April 10th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2024-04-10T11:56:20+00:00","versionOfRecord":[],"versionCreatedAt":"2024-04-10 11:56:20","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4221664","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4221664","identity":"rs-4221664","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}