Physician Service Attribution Methods for Examining Provision of Low-Value Care

Abstract

Objectives: There has been significant research on provider attribution for quality and cost. Low-value care is an area of heightened focus, with little of the focus being on measurement; a key methodological decision is how to attribute delivered services and procedures. We illustrate the difference in relative and absolute physician- and panel-attributed services and procedures using overuse in cervical cancer screening.

Study design: A retrospective, cross-sectional study in an integrated health care system.

Methods: We used 2013 physician-level data from Group Health Cooperative to calculate two utilization attributions: (1) panel attribution with the procedure assigned to the physician's predetermined panel, regardless of who performed the procedure; and (2) physician attribution with the procedure assigned to the performing physician. We calculated the percentage of low-value cervical cancer screening tests and ranked physicians within the clinic using the two utilization attribution methods.

Results: The percentage of low-value cervical cancer screening varied substantially between physician and panel attributions. Across the whole delivery system, median panel- and physician-attributed percentages were 15 percent and 10 percent, respectively. Among sampled clinics, panel-attributed percentages ranged between 10 percent and 17 percent, and physician-attributed percentages ranged between 9 percent and 13 percent. Within a clinic, median panel-attributed screening percentage was 17 percent (range 0 percent-27 percent) and physician-attributed percentage was 11 percent (range 0 percent-24 percent); physician rank varied by attribution method.

Conclusions: The attribution method is an important methodological decision when developing low-value care measures since measures may ultimately have an impact on national benchmarking and quality scores. Cross-organizational dialogue and transparency in low-value care measurement will become increasingly important for all stakeholders.

Keywords: Informatics; Learning Health System; Quality measurement.

Figure 1.

Panel and Physician Attribution Percentages of Over-Pap Tests for One Clinic in an Integrated Delivery System Figure 1a. Panel-Attributed Over-Pap Percentages at One Clinic Figure 1b. Physician-Attributed Over-Pap Percentages at One Clinic Notes: An “over-Pap” was defined as “a Pap test that fell between 15 months and 30 months from a prior Pap among women ages 21 to 65 years.” Paneled physicians were included if they had ≥5 panel-or physician-attributed Pap tests. Panel-attributed percentages are the number of over-Paps performed on women within the physician’s panel divided by the total number of Pap tests performed on women within the physician’s panel. Physician-attributed percentages are the number of over-Paps performed by a given physician divided by the total number of Pap tests performed by the physician.