Is there an association between hospital occupancy and quality of care?

Abstract

Statement of the problem. Hospital occupancy is the number of inpatients divided by the number of beds. It has risen over the last two decades in many countries. This thesis will determine if there is an association between hospital occupancy and quality of care. Setting. The Ottawa Hospital - Civic Campus, a tertiary care teaching hospital in Ottawa, Canada between January 1, 1993 and July 31, 1999. Methods. Daily rates of hospital occupancy and several quality of care indicators were derived using administrative databases. Indicators included: efficiency outcomes (emergency room (ER) delay, hospital length of stay (LOS), off service transfers, bed to bed transfers, and operating room (OR) cancellations); inpatient outcomes (deaths, cardiac arrests, c. difficile infections, medication errors, and falls); and outpatient outcomes (7- and 30-day visits to any ER, urgent readmissions to any hospital, and deaths). Autoregressive Integrated Moving Average (ARIMA) time-series modeling was used to test the association between hospital occupancy and each of the outcomes. Results. Significant, positive associations were identified between daily occupancy rates and the following outcomes: ER delay, off service transfer, bed to bed transfers, and the proportion of patients dying within 30 days of discharge. Significant negative associations were identified between occupancy and length of stay and hospital deaths. Conclusion. This study demonstrates that quality of care is associated with hospital occupancy. Further research is required to validate the clinical importance of the efficiency indicators used and to adjust occupancy for case-mix.