Interprovincial Variation in Access to Publicly Funded Pharmaceuticals

Abstract

Introduction: Government-funded drug programs provide prescription medications for many Canadian residents, including senior citizens and social assistance recipients. Pharmaceuticals available for beneficiaries are typically listed in federal, provincial, and territorial formularies. We analyzed six Canadian drug formularies (for the provinces of Alberta, British Columbia, Manitoba, Nova Scotia, Ontario, and Quebec) and report the extent of interprovincial variation in Canadians' access to publicly funded pharmaceuticals at the chemical subgroup (CSG) level of the World Health Organization Anatomical Therapeutic Chemical (WHO ATC) classification system. Methods: A database profiling provincial formulary listings of CSGs was compiled to enable a cross-sectional analysis of drug benefits at a clinically meaningful level. The comprehensiveness of provincial drug reimbursement plans was evaluated in a quantitative comparison of CSGs. Therapeutic distribution of CSGs within anatomical main groups of the WHO ATC classification system was also investigated. Interprovincial formulary agreement of CSG listings (full, restricted, or not listed) was determined on the basis of kappa coefficients. Results: British Columbia and Nova Scotia provided residents with access to the greatest number of full-listing CSGs, 336 each. Manitoba had the fewest full-listing CSGs, 268. Kappa coefficients, representing agreement in provincial listing decisions, ranged from 0.23 (between British Columbia and Quebec) to 0.45 (between Alberta and Manitoba). All of these coefficients represent a fair-to-poor level of interprovincial agreement in CSG listing status. Conclusion: A large degree of variation is present in Canadian provincial drug formularies, even at the CSG level. This reflects differences in provincial listing decisions and has therapeutic implications for patients, in that there is differential access to entire categories of drug products across provincial drug plans.