These data notes provide you with information on the Canadian Community Health Survey (CCHS), as well as methods and limitations associated with CCHS health indicator reports produced by the Halton Region Health Department. View other health indicator reports.
The Canadian Community Health Survey is a voluntary, cross-sectional survey that collects information related to health status, health system utilization and health determinants for the Canadian population. CCHS is conducted by Statistics Canada.
Each year, CCHS surveys 65,000 people aged 12 and over from across Canada. The survey provides health information at the provincial and regional levels. CCHS is designed to provide reliable estimates at the health unit level every 2 years.
The information collected in these surveys is used by the Health Department to produce health indicator reports which support program planning and evaluation, policy development, and help to improve awareness of health issues in the community.
In order for estimates produced from CCHS data to be representative of the population, and not just the sample itself, weights are used during analysis. A weight is given to each respondent in the sample, which corresponds to the number of people in the entire population that are represented by the respondent.1
In the health indicator reports comparisons are typically done by sex, age, municipality, income and education for questions related to individuals, and by municipality and income for questions related to households. Comparisons over time are also presented when multiple years of data are available. Comparisons can be made between Halton and Ontario as provincial data is available for CCHS.
It is not recommended to compare CCHS data from the 2015 cycle onwards to past CCHS data due to a redesign of the survey.
Statistical significance and variation
Overlapping 95% confidence intervals (CIs) are used to determine statistical significance in health indicator reports. A 95% confidence interval refers to a range of values that have a 95% chance of including the true estimate. When CIs do not overlap between 2 or more groups (e.g. when comparing males and females) it means that the differences between the groups are statistically significant and unlikely to be due to chance alone. Since overlapping confidence intervals are used to determine statistical significance, p-values are not calculated. This is a conservative approach which is more appropriate when multiple comparisons are being made, such as in health indicator reports. CIs are used to determine statistical significance, however CIs are not always presented in health indicator reports.
Coefficient of variation (CV) refers to the precision of an estimate. When the CV is between 15.0 and 35.0, the estimate should be interpreted with caution due to high variability and marginal precision, and has been marked with an asterisk (*). Estimates with a CV of greater than 35.0 are not reportable and have been marked with double asterisks (**) in the figures and tables. Please note that the ranges for marginal and unreportable precision have changed for 2015/16 compared to past reports.
Bootstrapping techniques are used to produce the coefficient of variation and the 95% confidence intervals.
The CCHS income variable is based on household income, adjusted by the before-tax low income cut-off (LICO) for the household and community size. The LICO is the threshold at which a family would typically spend a larger proportion of its income than the average family on the necessities of food, shelter, and clothing. This accounts for spending power based on the family and community size. These adjusted incomes for Halton residents are then organized into 5 equal groups (quintiles), from lowest (Q1) to highest (Q5).2
CCHS results are self-reported and may not be recalled accurately. 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 institutionalized population, and children aged 12-17 that are living in foster care. The survey is offered in both official languages, English and French.
Rounded estimates are used for the presentation of data, therefore estimates may not total 100%.
Don’t know and refused responses are typically excluded from the analysis. When “don’t know” is considered a valid response, or when over 5% of respondents answer “don't know”, the response is included in the analysis.
Some analyses are limited by sample size.
- Statistics Canada. 2018. Canadian Community Health Survey. Accessed August 2018 (external link)
- Statistics Canada. 2017. Health Fact Sheets –Smoking, 2016. Accessed August 2018 (external link)
In 2012, CCHS began work on a major redesign project that was completed and implemented for the 2015 cycle.
As a result of the redesign, the 2015 CCHS has a new collection and sampling strategy and has undergone major content revisions.
Therefore, caution should be taken when comparing data from previous cycles to data release for the 2015 cycle onwards.