Data Sources

The work at CNODES uses population databases from seven Canadian provinces and two international databases (UK CPRD and US MarketScan), with additional databases from the Atlantic provinces on the way. Altogether, these databases include over 100 million patients.

Types of Data Used

The data are typical of those obtained from administrative health data sources, including registrant files, vital statistics and provincial publicly-funded health insurance claims. These insurance claims include drug claims, hospital discharge abstracts, physician claims, and at some sites, data on vaccines, emergency department visits, outpatient laboratory data, a linked cancer registry and a pregnancy registry.

Each site or province has access to different data, as summarized in the table below:

International databases

CNODES studies often include data from the United Kingdom CPRD which contains extracts of primary care medical records for more than 14 million individuals enrolled in more than 680 general practices. While the information obtained from CPRD stems from electronic medical records, the fields are similar to those obtained from Canadian provincial administrative datasets. CNODES also works with the American MarketScan database, which contains medical information on individuals and their dependents insured by United States private health insurance plans.

Linking with EMR databases

To explore the added value of data from electronic medical records (EMR), CNODES is currently working on an EMR linkage project at its Ontario site. Administrative data at the Institute for Clinical Evaluative Sciences (ICES) is in the process of being linked with the Electronic Medical Record Administrative data Linked Database (EMRALD) at ICES. The administrative data will also be linked with EMR data from the University of Toronto Practice-Based Research Network (UTOPIAN), part of the larger Canadian Primary Care Sentinel Surveillance Network (CPCSSN).