1. a Department of Health Care and Epidemiology , University of British Columbia , British Columbia , Canada
2. b Department of Medicine , University of British Columbia , British Columbia , Canada
3. c Centre for Health Evaluation and Outcome Sciences , St. Paul's Hospital , British Columbia , Canada
4. d British Columbia Centre for Excellence in HIV/AIDS , St. Paul's Hospital , British Columbia , Canada
5. e Outpatient Pharmacy Department , St. Paul's Hospital, Vancouver , British Columbia , Canada