Cohorts and data sources
Isotretinoin User Cohort
The Isotretinoin User Cohort was put in place by Dr. Anick Bérard's research team at CHU Sainte-Justine in Montreal. This database was built by the linkage of data from the Régie de l'Assurance Maladie du Québec (RAMQ) and Med-Écho administrative databases.
The RAMQ database contains information on medical services (diagnosis and procedures) received by all Quebec residents. Although RAMQ covers all residents of Quebec for the cost of physician visits, hospitalisations, and procedures, it does not universally cover the cost of medications. The RAMQ prescription claims database (RAMQ-Rx) covers individuals 65 years and older, welfare recipients, and workers and their families who do not have access to a private drug insurance plan. Individuals covered by the RAMQ prescription plan account for approximately 43% of the overall Quebec population. MedEcho is a provincial database that records acute care hospitalisation data, including emergency visits, for all Quebec residents. The Isotretinoin User Cohort contains data on individuals suffering from acne vulgaris from 1984 to 2003, for a total of 30,496 isotretinoin users.
Access to data needed for the creation of the Isotretinoin User Cohort was approved by the Commission d'accès à l'information du Québec (CAI).
Canadian Institutes of Health Research (CIHR).