Impact of physician assistant care on office visit resource use in the United States

Abstract

Objective: To investigate whether the use of physician assistants (PAs) as providers for a substantive portion of a patient's office-based visits affects office visit resource use.

Data source: Medical Expenditure Panel Survey (MEPS) Household Component data from 1996 to 2004.

Study design: This retrospective cohort study compares the number of office-based visits per year between adults for whom PAs provided >or=30 percent of visits and adults cared for by physicians only.

Data collection/extraction methods: The Agency for Healthcare Research and Quality collects MEPS data using methods designed to produce data representative of the U.S. noninstitutionalized civilian population. Negative binomial regression was used to compare the number of visits per year between persons with and without PA care, adjusted for demographic, geographic, and socioeconomic factors; insurance status; health status; and medical conditions.

Principal findings: After case-mix adjustment, patients for whom PAs provided a substantive portion of care used about 16 percent fewer office-based visits per year than patients cared for by physicians only. This difference in the use of office-based visits was not offset by increased office visit resource use in other settings.

Conclusions: Results indicate that the inclusion of PAs in the U.S. provider mix does not affect overall office visit resource use.

Figure 1

Incidence Rate Ratios for the PA+ group Compared with the Physician-Only Group at Different Cut-Points for Percent of Visits to PAs^{* *}Population-adjusted incidence risk ratio showing proportionate contrast in expected number of office visits over the 1-year period for the exposed (PA+) group compared with the control (physician-only) group. Incidence risk ratio was not statistically significant at the 10 percent cut-point.