An Evaluation of Sampling Design for Estimating an Epidemiologic Volume of Diabetes and for Assessing Present Status of Its Control in Korea Ji-Sung Lee, Jaiyong Kim 1) , Sei-Hyun Baik 2) , Ie-Byung Park 3) , Juneyoung Lee 4) Department of Public Health, Korea University Graduate School, Department of Social and Preventive Medicine, College of Medicine, Hallym University 1) , Department of Internal Medicine, College of Medicine, Korea University 2) , Department of Endocrinology of Metabolism, Gachon University of Science and Medicine 3) , Department of Biostatistics, College of Medicine, Korea University 4) Objectives : An appropriate sampling strategy for estimating an epidemiologic volume of diabetes has been evaluated through a simulation. Methods : We analyzed about 250 million medical insurance claims data submitted to the Health Insurance Review & Assessment Service with diabetes as principal or subsequent diagnoses, more than or equal to once per year, in 2003. The database was re-constructed to a patient-hospital profile that had 3,676,164 cases, and then to a patient profile that consisted of 2,412,082 observations. The patient profile data was then used to test the validity of a proposed sampling frame and methods of sampling to develop diabetic-related epidemiologic indices. Results : Simulation study showed that a use of a stratified two-stage cluster sampling design with a total sample size of 4,000 will provide an estimate of 57.04% (95% prediction range, 49.83 - 64.24%) for a treatment prescription rate of diabetes. The proposed sampling design consists, at first, stratifying the area of the nation into metropolitan/city/county and the types of hospital into tertiary/secondary/primary/clinic with a proportion of 5:10:10:75. Hospitals were then randomly selected within the strata as a primary sampling unit, followed by a random selection of patients within the hospitals as a secondly sampling unit. The difference between the estimate and the parameter value was projected to be less than 0.3%. Conclusions : The sampling scheme proposed will be applied to a subsequent nationwide field survey not only for estimating the epidemiologic volume of diabetes but also for assessing the present status of nationwide diabetes control. J Prev Med Public Health 2009;42(2):135-142 Key words : Simulation, Diabetes mellitus, Epidemiologic indices, Insurance claim review data, Stratified two-stage cluster sampling J Prev Med Public Health 2009;42(2):135-142 DOI: 10.3961/jpmph.2009.42.2.135 . 1990 6 30 [1] 2005 [2]. , , , [3]. , , , , (National Diabetes Program) . ( ) , , , 2004 11