Quality of US primary care delivered by resident and staff physicians.

BACKGROUND: Few population-based data are available on the quality of outpatient care provided by resident physicians in the US.
OBJECTIVE: To assess the quality of outpatient care delivered by resident and staff physicians.
DESIGN: Cross-sectional analysis. We used chi-square tests to compare resident and staff physician performance on 19 quality indicators. Using multivariable logistic regression, we controlled for sex, age, race/ethnicity, insurance, and metropolitan status. PARTICIPANTS: 33,900 hospital-based outpatient visits from the 1997-2004 National Hospital Ambulatory Medical Care Survey (NHAMCS). MEASUREMENTS: Resident and staff physician performance on 19 quality indicators.
RESULTS: Resident physicians were more likely to care for younger, non-white, female, urban, and Medicaid-insured patients. In both adjusted and unadjusted analyses, residents outperformed staff on four of 19 measures including angiotensin converting enzyme inhibitor use for congestive heart failure (57.0% vs. 27.6%; p=<0.001), diuretic use for hypertension (57.8% vs. 44.0%; p=<0.001), statin use for hyperlipidemia (56.3% vs. 40.4%; p=0.001), and routine blood pressure screening (85.3% vs. 79.6%; p=0.02). Residents and staff performed at similar levels for counseling (range 15.7 to 32.0%). Residents and staff performed similarly well on measures capturing inappropriate prescribing or overuse of diagnostic testing (range 48.6 to 100%). Residents and staff performed similarly on measures of appropriate prescribing (range from 30.9% to 69.2%).
CONCLUSIONS: Primary care provided by resident physicians is of similar or higher quality than that provided by staff physicians. Significant opportunity remains to improve quality of outpatient care provided by all physicians. Residency training programs should devote attention to improving outpatient quality of care delivered by residents.