One laudable goal is to improve medical quality while reducing cost. One way members of Congress have proposed to accomplish this is to use episode groupers in order to provide feedback to doctors regarding their resource use. None other than Max Baucus has advocated this (see p. 45 of this white paper).
However, matching patient costs to individual physicians is difficult. A paper by Pham et al. (NEJM 2007) shows that Medicare beneficiaries see many physicians in the course of a year or even during the course of the treatment for one disease. “Beneficiaries saw a median of two primary care physicians and five specialists working in four different practices.”
The authors explore 4 methods to attribute patient episodes to individual physicians:
- Plurality provider algorithm. Assigns a beneficiary to the physician (or practice) who billed for the greatest number of that beneficiary’s evaluation and management visits
- Plurality primary care physician algorithm. This method excludes specialist visits and assigns the beneficiary to the primary care physician billing for the most evaluation and management visits.
- Majority provider algorithm. Assigns the beneficiary to the provider who billed for the plurality of evaluation and management visits, with the added criterion that the plurality must be at least 50% of those visits.
- Multiple provider algorithm. Assigns the beneficiary to all providers who billed for at least 25% of the beneficiary’s evaluation and management visits, thereby allowing the beneficiary’s care to be assigned to more than one provider.
Using these methodologies, Pham and co-authors found that “Between 2000 and 2001, and again between 2001 and 2002, an average of 33% of beneficiaries had a change in their assigned physician, with that assignment changing to a different practice for the vast majority (97%).”
Further, because a physician must account for the majority of the patient’s episode-level visits, many of the physician’s patient visits will be excluded from their score. In the CTS data from the Pham study, only “39% of a primary care physician’s Medicare patients, and 6% of a medical specialist’s Medicare patients, were assigned to them.” Patient with chronic illnesses are more likely to have multiple physicians and are less likely to have their care episodes assigned to a primary care physician.
This persistent instability “may decrease the motivation of physicians to invest in long-term improvements in care for patients with chronic conditions (e.g., hiring patient educators), or the ability to target interventions to specific patients, if they perceive that the benefits to patients will take years to accrue and that many of their patients are unlikely to remain assigned to them. Care dispersion may thus limit the motivation of physicians and their ability to improve the quality of care in multiple ways.”
- Source: Hoangmai H. Pham, Deborah Schrag, Ann S. O’Malley, Beny Wu, Peter B. Bach (2007) “Care Patterns in Medicare and Their Implications for Pay for Performance” NEJM, v356(11):1130-1139, March 15, 2007.