Short-term effects of a pay-for-performance programme for diabetes in a primary care setting: an observational study

OBJECTIVE A pay-for-performance (P4P) programme for primary care was introduced in 2011 by a Swedish county (with 1.6 million inhabitants). Effects on register entry practice and comparability of data for patients with diabetes mellitus were assessed. DESIGN AND SETTING Observational study analysing short-term outcomes before and after introduction of a P4P programme in the study county as compared with a reference county. SUBJECTS A total of 84 053 patients reported to the National Diabetes Register by 349 primary care units. MAIN OUTCOME MEASURES Completeness of data, level and target achievement of glycated haemoglobin (HbA1c), blood pressure (BP), and LDL cholesterol (LDL). RESULTS In the study county, newly recruited patients who were entered during the incentive programme were less well controlled than existing patients in the register - they had higher HbA1c (54.9 [54.5-55.4] vs. 53.7 [53.6-53.9] mmol/mol), BP, and LDL. The percentage of patients with entry of BP, HbA1c, LDL, albuminuria, and smoking increased in the study county but not in the reference county (+26.3% vs -1.5%). In the study county, with an incentive for BP < 130/80 mmHg, BP data entry behaviour was altered with an increased preference for sub-target BP values and a decline in zero end-digit readings (38.3% vs. 33.7%, p < 0.001). CONCLUSION P4P led to increased register entry, increased completeness of data, and altered BP entry behaviour. Analysis of newly added patients and data shows that missing patients and data can cause performance to be overestimated. Potential effects on reporting quality should be considered when designing payment programmes. Key points A pay-for-performance programme, with a focus on data entry, was introduced in a primary care region in Sweden. Register data entry in the National Diabetes Register increased and registration behaviour was altered, especially for blood pressure. Newly entered patients and data during the incentive programme were less well controlled. Missing data in a quality register can cause performance to be overestimated.