Payment for performance: in sickness and in health. For better or for worse?

American consumers and payers are increasingly questioning the value of health care as costs increase amid reports of poor quality. Rewarding health care providers who apply evidence-based, clinical practice guidelines (CPGs) to obtain desired patient outcomes seems an intuitive, innovative method to improve health care value. Although there are many unanswered questions about payment for performance (P4P), Congress and the Centers for Medicare and Medicaid Services are developing a rapid timetable to begin P4P. Many private payers have already begun P4P programs. Currently, we lack randomized, controlled studies proving the safety, effectiveness, and patient centeredness of P4P. Many see publicly reporting provider performance as a surrogate for P4P. There is a growing literature documenting the effect of publicly reporting provider performance on the medical community and patient outcomes. It changes provider behavior, but occasionally, in undesirable ways (for example, adverse risk selection, or 'cherry picking'). Publicly reporting or rewarding provider performance based on applying evidence-based CPGs may also have unforeseen negative patient outcomes. P4P should proceed carefully while considering unintended consequences for patients and providers. P4P should be pilot tested in the proper target patient and provider populations. Thus, we need to study how CPGs interact with one another in specific patient populations. The updating process for CPGs should include evidence-based statements concerning their impact on real patients with multiple chronic illnesses.