Background: Considerable amount of inappropriate antibiotic utilization has been observed in both acute and non-acute care hospitals. Literature has shown that strategies such as an order entry (OE) and computer decision support system (DSS) have improved prescribing practices in acute care settings. However, there is limited research on the effect of OE on antibiotic utilization in non-acute care settings. Objective: To determine the relationship between OE with DSS and antibiotic utilization in a complex continuing care and rehabilitation hospital. Methods: A retrospective analysis of OE and Pharmacy dispensing data, prospectively collected between July 1, 1999 and December 31, 2005, was conducted. Dispensing events for oral and intravenous antibiotics were merged with corresponding OE’s (when present) to form a final database of 4,739 dispensing events with 2,397 OE’s. The presence of OE and the proportion of OE to dispensing events formed the exposure variable while antibiotic utilization in defined daily dose (DDD) was calculated using dose and number of doses of an antibiotic. Antibiotic utilization was examined at the hospital and individual service in-patient unit levels (complex continuing care/CCC and rehabilitation medicine/REH). Statistical analysis consisting of multiple regression modeling was conducted to determine the association between use of OE and antibiotic utilization. Results: A best-fit model using multiple regression analysis at hospital level indicated a significant positive relationship between the presence of OE and antibiotic utilization when service, patient age, gender and antibiotic classes were accounted for. This model explained 11% of the variation in antibiotic utilization. No significant associations were found in the CCC in-patient unit while in the REH in-patient unit a significant positive relationship between the presence of OE and antibiotic utilization was observed. Similarly, antibiotic utilization increased significantly with increase in the proportion of OE to dispensing events at the hospital and REH in-patient unit levels but not in the CCC in-patient unit. Conclusion: The results of this study demonstrate that antibiotic utilization increased over the years following the inception of the OE system with DSS at the study hospital. Further research is required to examine the effect of OE with a rudimentary DSS on antibiotic utilization management in non-acute care. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2007-07-13 10:47:38.035