Background We evaluated the validity and reliability of the operational definition of type 2 diabetes mellitus (T2DM) based on the Korean National Health Insurance Service (NHIS) database.
Methods Adult subjects (≥40 years old) included in the Korea National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2017 were merged with those from the NHIS health check-up database, producing a cross-sectional dataset. We evaluated the sensitivity, specificity, accuracy, and agreement of the NHIS criteria for defining T2DM by comparing them with the KNHANES criteria as a standard reference.
Results In the study population (n=13,006), two algorithms were devised to determine from the NHIS dataset whether the diagnostic claim codes for T2DM were accompanied by prescription codes for anti-diabetic drugs (algorithm 1) or not (algorithm 2). Using these algorithms, the prevalence of T2DM was 14.9% (n=1,942; algorithm 1) and 20.8% (n=2,707; algorithm 2). Good reliability in defining T2DM was observed for both algorithms (Kappa index, 0.73 [algorithm 1], 0.63 [algorithm 2]). However, the accuracy (0.93 vs. 0.89) and specificity (0.96 vs. 0.90) tended to be higher for algorithm 1 than for algorithm 2. The validity (accuracy, ranging from 0.91 to 0.95) and reliability (Kappa index, ranging from 0.68 to 0.78) of defining T2DM by NHIS criteria were independent of age, sex, socioeconomic status, and accompanied hypertension or dyslipidemia.
Conclusion The operational definition of T2DM based on population-based NHIS claims data, including diagnostic codes and prescription codes, could be a valid tool to identify individuals with T2DM in the Korean population.
Citations
Citations to this article as recorded by
Big Data Research for Diabetes-Related Diseases Using the Korean National Health Information Database Kyung-Soo Kim, Bongseong Kim, Kyungdo Han Diabetes & Metabolism Journal.2025; 49(1): 13. CrossRef
Metabolic dysfunction-associated fatty liver disease increases the risk of type 2 diabetes mellitus in young Korean adults Junchul Ha, Oak-Kee Hong, Kyungdo Han, Hyuk-Sang Kwon Diabetes Research and Clinical Practice.2024; 212: 111584. CrossRef
Association between Age at Diagnosis of Type 2 Diabetes and Subsequent Risk of Dementia and Its Major Subtypes Da Hea Seo, Mina Kim, Yongin Cho, Seong Hee Ahn, Seongbin Hong, So Hun Kim Journal of Clinical Medicine.2024; 13(15): 4386. CrossRef
Gamma‐glutamyl transferase and the risk of all‐cause and disease‐specific mortality in patients with diabetes: A nationwide cohort study Goh Eun Chung, Su‐Min Jeong, Su Jong Yu, Jeong‐Ju Yoo, Yuri Cho, Kyu‐na Lee, Dong Wook Shin, Yoon Jun Kim, Jung‐Hwan Yoon, Kyungdo Han, Eun Ju Cho Journal of Diabetes.2024;[Epub] CrossRef
Association between exercise habits and incident type 2 diabetes mellitus in patients with thyroid cancer: nationwide population-based study Jiyun Park, Jin-Hyung Jung, Hyunju Park, Young Shin Song, Soo-Kyung Kim, Yong-Wook Cho, Kyungdo Han, Kyung-Soo Kim BMC Medicine.2024;[Epub] CrossRef
Association Between Benzene and Other Volatile Organic Compounds Exposure and Diabetes Mellitus Among Korean Adults: Findings from the Nationwide Biomonitoring Data Seong-Uk Baek, Minseo Choi, Yu-Min Lee, Jin-Ha Yoon Exposure and Health.2024;[Epub] CrossRef
All-cause and cause-specific mortality risks in individuals with diabetes living alone: A large-scale population-based cohort study Jae-Seung Yun, Kyungdo Han, Bongseong Kim, Seung-Hyun Ko, Hyuk-Sang Kwon, Yu-Bae Ahn, Yong-Moon Mark Park, Seung-Hwan Lee Diabetes Research and Clinical Practice.2024; 217: 111876. CrossRef
Association between alcohol consumption and risk of developing tuberculosis in patients with diabetes: a nationwide retrospective cohort study Chiwook Chung, Kyu Na Lee, Kyungdo Han, Junhee Park, Dong Wook Shin, Sei Won Lee Respiratory Research.2024;[Epub] CrossRef
New-Onset Type 1 and Type 2 Diabetes Among Korean Youths During the COVID-19 Pandemic Da Hye Lee, Hwa Young Kim, Ji Young Park, Jaehyun Kim, Jae Hyeon Park JAMA Pediatrics.2024;[Epub] CrossRef
Risk of Cause-Specific Mortality across Glucose Spectrum in Elderly People: A Nationwide Population-Based Cohort Study Joonyub Lee, Hun-Sung Kim, Kee-Ho Song, Soon Jib Yoo, Kyungdo Han, Seung-Hwan Lee Endocrinology and Metabolism.2023; 38(5): 525. CrossRef