Methods
We analyzed several Quebec healthcare claims databases, in accordance
with the Strengthening the Reporting of Observational Studies in
Epidemiology (STROBE) guidelines.24 The need for
informed consent was waived by the local institutional research
committee (University of Montreal, Montreal, Quebec, Canada). The study
protocol complied with the ethical guidelines of the 1975 Declaration of
Helsinki and was approved by the institutional research committee of the
University of Montreal.