OUTCOMES? RESULTS OF A REGIONAL ANALYSIS. W.A. Barry 1 , G.E. Rosenthal 1 ; 1 University of Iowa Hospitals and Clinics and Iowa City VAMC, Iowa City, IA PURPOSE: Discontinuity of care in teaching hospitals may occur when teams rotate on and off service. The purpose of this study was to determine relationships between the timing of admission (during the month) and in-hospital mortality and length of stay (LOS) in patients admitted to intensive care units (ICUs). METHODS: We conducted a retrospective cohort study of 156,136 consecutive admissions (mean age 63.0 years, 51.7% male) to 38 ICUs in 28 hospitals in a large mid-western metropolitan area during 1991 ± 1997. Hospitals included 5 major (n = 48,853), 6 minor (n = 29,995), and 17 non-teaching (n = 77,288) facilities. Data were collected from patients' medical records. Admission severity of illness was measured using the APACHE III methodology. Multivariable analyses compared mortality for admissions on Days 1 ± 5, 6 ± 10, 11 ± 15, 16 ± 20, 21 ± 25 , and 26 ± 31 of each month, adjusting for severity of illness and month and weekday of admission. RESULTS: In-hospital mortality was higher in patients admitted on Days 1 ± 5, 6 ± 10, and 26 ± 31, compared to admissions on Days 11 ± 25 in major teaching hospitals (14.7%, 14.7%, 14.5%, and 10.9%, respectively; p < .01). Adjusting for severity of illness and other factors using logistic regression, the odds of death was higher in patients admitted to major teaching hospitals ICUs on Days 1 ± 10 or 26 ± 31, relative to patients admitted on Days 11 ± 25 (OR 1.11; 95% CI, 1.04 ± 1.18; p = .01). Adjusted odds of death were not higher during these periods in minor teaching (OR 1.03; 95% CI, 0.94 ± 1.13; p = .59) or non-teaching (OR 0.95; 95% CI, 0.90 ± 1.00; p = .07) hospitals. Results were similar when admissions on Days 1 ± 5, 6 ± 10, and 26 ± 31 were examined separately, as shown in the table below (data reflect OR (95% CI)).