Increasing attention is focused on the quality of healthcare provided in the United States, as well as options for controlling costs. Quality and cost measurements are important in assessing access to and satisfaction with healthcare services and managing cost and payment practices; a sufficient sample size of patients is necessary to reliably interpret the results and statistics. Making matters difficult is the fact that most physicians in this country do not see enough patients to detect meaningful differences in cost or quality performance, according to a recent report in the Journal of the American Medical Association (JAMA).

The authors of the JAMA study analyzed the performance of nearly 72,000 primary care physicians among more than 30,000 practices. More than 60% of the physicians were solo practitioners. The physicians were selected from the 2005 Medicare Part B 20% sample and the Healthcare Organization Services database. The researchers aimed to analyze the percentage of these primary care physicians who saw enough patients to detect a 10% difference between practices in 5 performance measures: average ambulatory Medicare spending, rate of mammography for women aged 66 to 69 years, rate of Hemoglobin A1C (HbA1C) testing for diabetics aged 66 to 75 years, rate of preventable hospitalizations, and 30-day readmission rate after discharge for congestive heart failure (CHF).

Overall, the physicians had a median Medicare caseload of 260 patients. Of these, 25 women were eligible for mammography, 30 diabetic patients were eligible for HbA1C testing, and 0 patients were hospitalized for CHF. Very few practices had a sufficient caseload to detect a 10% difference in performance, as measured by cost and quality outcomes. Less than 10% of small practices — those with less than 11 physicians — saw enough patients to accurately detect a difference in ambulatory costs or rate of mammography or HbA1C testing. Conversely, all of the large practices — those with more than 50 physicians — saw enough patients to precisely detect a difference in the same measures. However, none of the practices saw enough patients to detect a 10% difference in preventable hospitalizations or CHF readmission outcomes.

Payment of physicians is believed to influence their clinical practice. Several strategies are being discussed to provide payment or reimbursement to physicians, but no new standard is yet established and the impact on clinical behavior and decision-making is unclear. Fee-for-service payment, the most widely used payment method currently, does not relate to outcome measures or physician performance. Capitation provides a set reimbursement per patient and makes the physician ultimately responsible for costs. Payment with a direct salary does not take into account number of patients, quality of care, or cost, while pay-for-performance programs allocate payment based on patient results. Most of these scenarios require a measurement of healthcare quality and outcomes to guarantee fair and adequate payment. If physicians are not seeing enough patients to accurately measure quality outcomes, how can physician payment be determined? How can we pay for something that we cannot measure?

Many people argue that physicians already have caseloads that are too large, and those caseloads will likely get larger in the years to come.  This may provide enough data to evaluate outcome measures, but will the results be favorable? Will more patients lead to lower quality healthcare? Can quality ever be measured accurately across all patient populations, payment providers, and physicians?  With the changing landscape of healthcare, the wisdom of the different payment methods and the methods to measure performance need to be considered.

References

Tu K, Cauch-Dudek K, Chen Z. Comparison of primary care physician payment models in the management of hypertension. Can Fam Physician. Jul 2009;55(7):719-727.

Gosden T, Forland F, Kristiansen IS, Sutton M, Leese B, Giuffrida A, Sergison M, & Pedersen L (2000). Capitation, salary, fee-for-service and mixed systems of payment: effects on the behaviour of primary care physicians. Cochrane database of systematic reviews (Online) (3) PMID: 10908531

Landon, B., O’Malley, A., & Keegan, T. (2009). Can Choice of the Sample Population Affect Perceived Performance: Implications for Performance Assessment Journal of General Internal Medicine DOI: 10.1007/s11606-009-1153-z

Gosden, T., Forland, F., Kristiansen, I., Sutton, M., Leese, B., Giuffrida, A., Sergison, M., & Pedersen, L. (2001). Impact of payment method on behaviour of primary care physicians: a systematic review Journal of Health Services Research and Policy, 6 (1), 44-55 DOI: 10.1258/1355819011927198

Nyweide DJ, Weeks WB, Gottlieb DJ, Casalino LP, Fisher ES. Relationship of primary care physicians’ patient caseload with measurement of quality and cost performance. Jama. Dec 9 2009;302(22):2444-2450.

Satin DJ, Miles J. Performance-based bundled payments: potential benefits and burdens. Minn Med. Oct 2009;92(10):33-35.