Background: Continuity of care in primary care settings is crucial for managing diabetes. We aimed to statistically define and analyze continuity factors associated with demographics, clinical workforce, and geographical relationships.

Methods: We used 2014–2015 National Health Insurance Service claims data from the Korean registry, with 39,096 eligible outpatient attendance. We applied multivariable logistic regression to analyze factors that may affect the continuity of care indices for each patient: the most frequent provider continuity index (MFPCI), modified-modified continuity index (MMCI), and continuity of care index (COCI).

Results: The mean continuity of care indices were 0.90, 0.96, and 0.85 for MFPCI, MMCI and COCI, respectively. Among patient factors, old age ＞80 years (MFPCI: odds ratio [OR], 0.81; 95% confidence interval [CI], 0.74–0.89; MMCI: OR, 0.84; 95% CI, 0.76–0.92; and COCI: OR, 0.81; 95% CI, 0.74–0.89) and mild disability were strongly associated with lower continuity of care. Another significant factor was the residential area: the farther the patients lived from their primary care clinic, the lower the continuity of diabetes care (MFPCI: OR, 0.74; 95% CI, 0.70–0.78; MMCI: OR, 0.70; 95% CI, 0.66–0.73; and COCI: OR, 0.74; 95% CI, 0.70–0.78).

Conclusion: The geographical proximity of patients’ residential areas and clinic locations showed the strongest correlation as a continuity factor. Further efforts are needed to improve continuity of care to address the geographical imbalance in diabetic care.