title: Variation in outpatient oral antimicrobial use patterns among Canadian provinces, 2000 to 2010.
abstract: BACKGROUND
  The volume and patterns of antimicrobial drug use are key variables to consider when developing guidelines for prescribing, and programs to address stewardship and combat the increasing prevalence of antimicrobial resistant pathogens. Because drug programs are regulated at the provincial level, there is an expectation that antibiotic use may vary among provinces.
  
  
  OBJECTIVE
  To assess these potential differences according to province and time.
  
  
  METHODS
  Provincial antimicrobial prescribing data at the individual drug level were acquired from the Canadian Integrated Program for Antimicrobial Resistance Surveillance for 2000 to 2010. Data were used to calculate two yearly metrics: prescriptions per 1000 inhabitant-days and the average defined daily doses per prescription. The proportion of liquid oral prescriptions of total prescriptions was also calculated as a proxy measure for the proportion of prescriptions given to children versus adults. To assess the significance of provincial antimicrobial use, linear mixed models were developed for each metric, accounting for repeated measurements over time.
  
  
  RESULTS
  Significant differences among provinces were found, as well as significant changes in use over time. Newfoundland and Labrador was found to have significantly higher prescribing rates than all other provinces (P<0.001) in 2010, as well as the mean of all other provinces (P<0.001). In contrast, Quebec exhibited significantly lower prescribing than all other provinces (P<0.001 for all provinces except British Columbia, where P=0.024) and the mean of all other provinces (P<0.001).
  
  
  CONCLUSIONS
  Reports of reductions in antimicrobial use at the Canadian level are promising, especially prescribing to children; however, care must be taken to avoid the pitfall of the ecological fallacy. Reductions are not consistent among the provinces or among the classes of antimicrobial drugs dispensed in Canada.
authors.affiliation: Public Health Agency of Canada, Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Guelph, Ontario;
authors.forename: Shiona K
authors.initials: SK
authors.lastname: Glass-Kaastra
authors.affiliation: Public Health Agency of Canada, Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Guelph, Ontario;
authors.forename: Rita
authors.initials: R
authors.lastname: Finley
authors.affiliation: Division of Medical Microbiology, Island Medical Program, University of British Columbia;
authors.forename: Jim
authors.initials: J
authors.lastname: Hutchinson
authors.affiliation: British Columbia Centre for Disease Control, Vancouver, British Columbia; ; University of British Columbia, School of Population and Public Health, Vancouver, British Columbia;
authors.forename: David M
authors.initials: DM
authors.lastname: Patrick
authors.affiliation: University of Montreal, Department of Infectious Diseases and Microbiology, Hôpital Maisonneuve-Rosemont, Montreal, Quebec;
authors.forename: Karl
authors.initials: K
authors.lastname: Weiss
authors.affiliation: Department of Medicine, University of Calgary, Calgary, Alberta ; Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta ; Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta.
authors.forename: John
authors.initials: J
authors.lastname: Conly
keywords: Antimicrobial spending; Antimicrobial stewardship; Antimicrobial use; Prescribing patterns; Surveillance