Respondents with higher BMIs may be more likely to be in the non-response categories and therefore to be excluded from indicator calculation as of 2009.
Self-reported height and weight generally underestimate BMI. Starting in 2007, Statistics Canada conducts the Canadian Health Measures Survey (CHMS), which records physical measurements of height and weight. Estimates of overweight and obesity are available at the national level only.
Data for the Canadian Community Health Survey (CCHS) is collected yearly from a sample of approximately 65,000 respondents. CANSIM Table 105-0509 presents estimates from 2-year combined data and features estimates for all provinces and territories as well as for health regions. The 2-year combined data has higher precision (less variability) than annual estimates; annual CCHS estimates are not available at the health region level.
Some values have data quality flags that indicate "use with caution" or "suppressed" due to high coefficients of variation: health regions with small populations and results disaggregated by age group or sex within small regions.
The CCHS covers the population age 12 and older living in the 10 provinces and 3 territories. Excluded from the survey's coverage are
- Persons living on reserves and other Aboriginal settlements in the provinces
- Full-time members of the Canadian Forces
- The population of institutionalized persons
- Persons living in 2 Quebec health regions: Nunavik Region and Terres-Cries-de-la-Baie-James Region
Altogether, these exclusions represent less than 3% of the Canadian population age 12 and older.