BackgroundIn the Republic of Korea, which medical specialties should take the responsibility for primary care and what the role of primary care should be are still unclear. In this study, we focused on the comprehensiveness of primary care to identify related factors.MethodsThe National Health Insurance Service (NHIS)-National Sample Cohort is a population-based cohort, sampled in the 2002 NHIS database and followed up until 2015. We used data collected from January 2014 to December 2015, including 20,423,832 outpatient visits in 19,557 office-based clinics. The Korean government has designated 52 simple or minor disease groups (SMDGs) to enhance the experience of patients who attend primary care for managing those diseases. We assessed comprehensiveness for each clinic as the number of SMDGs treated in each clinic for 2 years. We also identified the factors related to higher comprehensiveness, using logistic regression for analysis.ResultsThe clinics included in the study had provided treatment for an average of 14 SMDGs during a 2-year period. Compared to general practitioners, internal medicine physicians presented higher comprehensiveness with an odds ratio (OR) of 2.29 (95% confidence interval [CI], 2.03–2.59), and family medicine physicians illustrated higher comprehensiveness (OR, 4.96; 95% CI, 3.59–6.83). Other specialties showed lower comprehensiveness than general practitioners. Clinics located in the capital city and metropolitan area tended to have lower comprehensiveness. Clinics hiring more doctors and having hospitalization facility showed higher comprehensiveness.ConclusionGeneral physician, internal medicine, and family medicine are the fields providing comprehensive medical care in Korea. Clinics located in metropolitan area and capital city show lower comprehensiveness. The number of physicians is related to higher comprehensiveness of clinics.