Ethics approval for this study was granted by the Health Sciences Human Research Ethics Board of Dalhousie University in January 2004.
Nova Scotia, a province on the east coast of Canada, has about 908 000 inhabitants, with roughly one-third living in or near the capital city, Halifax. The province’s health care system is organized into 9 DHAs, each of which is responsible for the delivery and administration of health care services to the population in a specific geographic area. The cost of all hospital services and in-hospital drugs is covered under the Canadian medicare system. There are 37 hospitals in Nova Scotia, of which 31 administered fluoroquinolones over the study period of April 1, 1997, to March 31, 2003. Given the low use of fluoroquinolones for children, the province’s only free-standing pediatric hospital was not included in this study (i.e., was excluded from the analysis entirely). At the time of the study, the only participating facility that offered infectious disease consultation services was the tertiary care centre located in Halifax and was included in all analyses.
The data for this study were obtained from 4 sources. The first type of data was purchasing data, expressed as drug volume and expenditures and obtained from the Provincial Drug Distribution Program. This program operates through the Capital District Health Authority in Halifax and since 1997 has been responsible for negotiation of contracts for all pharmaceuticals and provision of the drugs to all hospitals in the province. The fluoroquinolone antimicrobials investigated in this study (and their respective DDDs) were ciprofloxacin (oral 1 g, parenteral 0.5 g), gatifloxacin (oral and parenteral 0.4 g), levofloxacin (oral and parenteral 0.25 g), moxifloxacin (oral and parenteral 0.4 g), norfloxacin (oral 0.8 g), and ofloxacin (oral and parenteral 0.4 g). These are the “assumed average maintenance doses per day for a drug used for its main indication in adults”, as published by the WHO. Data on trovafloxacin were also available for this study, but this medication had minimal use within the province during the study period and has since been removed from the Canadian market, so no results for this drug are presented here. The second type of data was hospital data (the name of the hospital, the DHA in which it was located, and the number of acute care beds); this information was obtained from the NS Department of Health. The third type of data was the number of admissions to hospital for community-acquired pneumonia, which was retrieved from the Canadian Institute of Health Information discharge database (accessed through the NS Department of Health). The fourth type of data was information about hospital policies on antimicrobial use and therapeutic pathways, which was collected by a survey mailed to the director of pharmacy of each DHA. The survey contained questions on restriction policies, therapeutic pathways for 2 specific conditions, and step-down programs from IV to oral administration. The survey questionnaire was pilot-tested with druginformation and drug utilization evaluation pharmacists for clarity and readability. In addition, the survey was reviewed and discussed at an infectious diseases research-in-progress seminar hosted by the Capital District Health Authority, which was attended by microbiologists, infectious disease physicians, and pharmacists. The survey was revised on the basis of input from both groups.