• Multilevel model;
  • severity and comorbidity;
  • unintended consequences;
  • diabetes mellitus

Objective. Taiwan has instituted a pay-for-performance (P4P) program for diabetes mellitus (DM) patients that rewards doctors based in part on outcomes for their DM patients. Doctors are permitted to choose which of their DM patients are included in the P4P program. We test whether seriously ill DM patients are disproportionately excluded from the P4P program.

Data Source/Study Setting. This study utilizes data from the National Health Insurance (NHI) database in Taiwan for the period of January 2007 to December 2007. Our sample includes 146,481 DM-P4P patients (16.56 percent of the total) and 737,971 non-DM-P4P patients.

Data Collection/Extraction Methods. We use logistic and multilevel models to estimate the effects of patient and hospital characteristics on P4P selection.

Principal Findings. The results show that older patients and patients with more comorbidities or more severe conditions are prone to be excluded from P4P programs.

Conclusions. We found that DM patients are disproportionately excluded from P4P programs. Our results point to the importance of mandated participation and risk adjustment measures in P4P programs.