Does performance-based remuneration for individual health care practitioners affect patient care?: a systematic review.
Pay-for-performance (P4P) is increasingly touted as a means to improve health care quality. To evaluate the effect of P4P remuneration targeting individual health care providers. MEDLINE, EMBASE, Cochrane Library, OpenSIGLE, Canadian Evaluation Society Unpublished Literature Bank, New York Academy of Medicine Library Grey Literature Collection, and reference lists were searched up until June 2012. Two reviewers independently identified original research papers (randomized, controlled trials; interrupted time series; uncontrolled and controlled before-after studies; and cohort comparisons). Two reviewers independently extracted the data. The literature search identified 4 randomized, controlled trials; 5 interrupted time series; 3 controlled before-after studies; 1 nonrandomized, controlled study; 15 uncontrolled before-after studies; and 2 uncontrolled cohort studies. The variation in study quality, target conditions, and reported outcomes precluded meta-analysis. Uncontrolled studies (15 before-after studies, 2 cohort comparisons) suggested that P4P improves quality of care, but higher-quality studies with contemporaneous controls failed to confirm these findings. Two of the 4 randomized trials were negative, and the 2 statistically significant trials reported small incremental improvements in vaccination rates over usual care (absolute differences, 8.4 and 7.8 percentage points). Of the 5 interrupted time series, 2 did not detect any improvements in processes of care or clinical outcomes after P4P implementation, 1 reported initial statistically significant improvements in guideline adherence that dissipated over time, and 2 reported statistically significant improvements in blood pressure control in patients with diabetes balanced against statistically significant declines in hemoglobin A1c control. Few methodologically robust studies compare P4P with other payment models for individual practitioners; most are small observational studies of variable quality. The effect of P4P targeting individual practitioners on quality of care and outcomes remains largely uncertain. Implementation of P4P models should be accompanied by robust evaluation plans. None.