Toronto, ON, Canada: Institute for Clinical Evaluative Sciences (internal report).
Institute for Clinical Evaluative Sciences, Toronto, ON, Canada
Methods: We conducted a population-based cohort study using health administrative data from Ontario, Canada covering the period from April 1, 2002 to September 30, 2014.
Data Sources: Residents of Ontario have universal health insurance. The Ministry of Health and Long-Term Care (MOHLTC) is the single payer for all medically necessary services, covering all residents, providers, and hospitals. The following health administrative databases can be linked on an individual level to provide a health profile for each resident.
• The Registered Persons Database contains basic demographic information and date of death.
• The Canadian Institute of Health Information (CIHI) Discharge Abstract Database contains information on all discharges from acute care hospitals. Day surgery visits are reported in the CIHI National Ambulatory Care Reporting System. Both databases contain information on interventions and diagnoses relating to the hospital stay.
• The Ontario Health Insurance Plan physician claims database contains information on all services provided by physicians.
We also used a number of validated databases identifying Ontario residents who have physician diagnosed asthma, congestive heart failure, chronic obstructive pulmonary disease, diabetes, and hypertension, to identify chronic comorbidities.