The “July Effect”: A Look at July Medical Admissions in Teaching Hospitals

Purpose: We examined the effect of admission for myocardial infarction, heart failure, or pneumonia during the first academic quarter compared with all other quarters in teaching versus nonteaching hospitals on length of stay, cost, and mortality.

Methods: Using data 2011 Nationwide Inpatient Sample, multivariable modeling with an interaction term was used to test teaching hospital effect by academic quarter. Logistic regression was used for mortality and log-transformed linear models for cost and length of stay.

Results: Charlson Index scores were similar in teaching and nonteaching hospitals. Patients admitted to teaching hospitals for myocardial infarction in the first quarter had a higher risk-adjusted mortality (1.217; confidence interval, 1.147–1.290) than those admitted to a nonteaching hospital during the same quarter (0.849; confidence interval, 0.815–0.885). Mean cost heart failure admissions averaged $584 more, and the mean length of stay was longer (0.10; P = .0127), during the first academic quarter. These effects were not present for quarters 2 through 4.

Conclusions: This study suggests small increases in mortality among patients admitted with myocardial infarction in the first academic quarter compared with all other quarters in teaching versus nonteaching hospitals. Increased cost and longer stay were seen for those admitted with heart failure.