Effects of physician experience on costs and outcomes on an academic general medicine service: Results of a trial of hospitalists

Background: Hospitalists may decrease costs and improve outcomes in hospitalized patients, but existing evidence is limited and has not identified mechanisms for such effects. Objective: To study the costs and outcomes for patients on an academic general medicine service assigned to teams led by hospitalists and non hospitalists. Design: Cohort study. Setting: Academic general medicine service. Patients: 6511 patients admitted to the hospital from July 1997 through June 1999. Intervention: All patients admitted every fourth day were assigned to 1 of 2 hospitalists caring for inpatients 6 months each year or 1 of 58 nonhospitalists caring for inpatients 1 to 2 months each year. Measurements: Length of stay; inpatient costs; and 30-, 60, and 365-day mortality. Results: Patients assigned to hospitalists (24.8%) and nonhospitalists (75.2%) did not differ in age, race, sex, diagnosis mix, or Charlson index score. In year 1, average adjusted length of stay was 0.29 day shorter for patients cared for by hospitalists than by nonhospitalists (95% Cl, -0.66 to 0.06 day; P = 0.06); in year 2, average adjusted length of stay was 0.49 day shorter for patients cared for by hospitalists (Cl, -0.79 to -0.15 day; P = 0.01). Average adjusted costs were not significantly reduced for hospitalists compared with nonhospitalists in year 1 but were reduced by $782 in year 2 (Cl, -$1313 to -$187; P = 0.01). When years 1 and 2 were combined or when year 1 was analyzed alone, 30-day mortality was not significantly different for hospitalists and non hospitalists; however, 30-day mortality was 4.2% for hospitalists compared with 6.0% for nonhospitalists in year 2 (Cl for difference, 1.8 percentage points [-3.6 to -0.1 percentage points]; P = 0.04) and the adjusted relative risk was 0.65 (Cl, 0.44 to 0.96; P = 0.03). In multivariate analyses, resource use decreased with the physician's cumulative experience in caring for a patient's primary diagnosis. Mortality showed a similar pattern. Conclusions: Hospitalist care was associated with lower costs and short-term mortality in the second but not the first year of hospitalists' experience. Disease-specific physician experience may reduce resource use and improve patient outcomes; in addition, it may be an important determinant of the effectiveness of hospitalists.