Cohorts and sources of data

COEFFICIENTS STUDY
Administrative databases are increasingly being used for pharmacoepidemiologic research. In fact, these sources of data offer many advantages such as very large sample sizes, evaluation of the true efficiency and security of treatment in a reasonable time, and population-based data which cover the entire population of a geographical region and are thus useful for public health decision. Moreover, studies using administrative databases are conducted more rapidly and are less expensive than field studies. However, the use of administrative databases is however criticised because they usually contain no information on clinical variables or socioeconomic risk factors.

Therefore, the COEFFICIENTS study aims to create adjustment coefficients for unmeasured confounders in the calculation of risk estimates using data from the most frequently used administrative databases in the province of Quebec: the Régie de l'Assurance Maladie du Québec (RAMQ) and the MedEcho database. These coefficients will allow to adjust risk estimates for the lack of information on lifestyle, socioeconomic variables, or clinical variables that will be collected by the mean of self-administered questionnaires.

The calculation of coefficients will be achieved according to the method described by Schneeweiss, 2006. Four different cohorts (n = 5000) will be sampled: 1) individuals 65 years and older cohort, 2) welfare recipients cohort, 3) adherents to the RAMQ drug insurance plan, and 4) individuals insured by private drug insurance plans; Subsequently, self-administered questionnaires will be send to subjects of these cohorts.

Access to data needed for the creation of the COEFFICIENTS Study cohort was in evaluation at the Commission d'accès à l'information du Québec (CAI). The protocol was already approved by CHU Sainte-Justine's ethics committee.

The COEFFICIENTS study will be unique and will benefit all researchers using administrative databases in the province of Quebec such as the RAMQ and MedEcho. Ultimately, this research platform will provide a greater visibility to results rising from the use of these sources of data and increase recognition and competitiveness of researchers using administrative databases in the province of Québec at the national and international levels.

Funding source
Fonds de la Recherche du Québec (FRSQ)