Health Statistics Data Notes

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 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.

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.

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.

• Canadian Community Health Survey – Annual component (external link) - Statistics Canada
• Halton health indicator and health status reports - Halton Region

The Rapid Risk Factor Surveillance System is an on-going telephone survey (land line and cell phone) used to collect information on attitudes, behaviours, knowledge and awareness of issues related to health in Halton. RRFSS is conducted by the Institute of Social Research at York University.

Since 2001, each year a random sample of approximately 1,200 adults aged 18 and over are surveyed in Halton Region. The information collected in these surveys is used by the Halton Region 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.

Analysis of RRFSS data uses dual-frame sampling weights to account for the two different sampling frames (landline and cellphone) and for the probability of being selected to complete the survey. For instance, the weights adjust for the fact that in landline sample, an adult from a household with a large number of adults is less likely to be selected to complete the survey than an adult who lives alone.

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.

It is not recommended to compare RRFSS data from 2016 onwards to previous RRFSS data due to changes in sampling and analysis methodology. For example, beginning in 2016 a cell phone sample was included and surveyors started asking to speak to individuals aged 18-30 first in order to boost the number of young adults included in the survey sample.

Income groups are determined by first asking respondents about their household income. If respondents refuse to provide their household income they are then asked to provide a range of income and the midpoint of the range is used to estimate household income. Second, the respondent’s adjusted household income is calculated by dividing household income by the square root of their household size. Adjusted household income reflects the fact that a household’s needs increase as the number of members increase. The adjusted household income for all Halton respondents are then organized into 10 equal deciles and placed into low (decile 1-3), middle (decile 4-7) and high (decile 8-10) income groups. Respondents who do not know or refuse to provide their household income (about 15% of respondents) are excluded from the income analysis.

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 16.6 and 33.3, the estimate should be interpreted with caution because of high variability, and has been marked with an asterisk (*). Estimates with a CV of greater than 33.3 are not reportable and have been marked with double asterisks (**) in the figures and tables.

RRFSS results are self-reported and may not be recalled accurately. Individuals not living in households (such as those in prison, hospitals, or the homeless) are excluded. As a result, the percentages may not represent the true estimates for the general population. In Halton, the survey is administered in English only.

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.

• Rapid Risk Factor Surveillance System (external link)
• Halton health indicator and health status reports - Halton Region

The Canadian Health Survey on Children and Youth is a voluntary survey that collects information related to health status, health system utilization and health determinants for Canadian children and youth. CHSCY is conducted by Statistics Canada and is designed to provide reliable estimates across age groups and at the provincial level. Within Ontario, the survey was also designed to provide reliable estimates at the sub-LHIN level in 2019 and at the health region level in 2023.^3,4

The sampling frame for CHSCY is the Canada Child Benefit file, which covers 98% of the Canadian population aged 1 to 17. Excluded from the survey are children and youth living on First Nation reserves and other Aboriginal settlements, children and youth living in foster homes and the institutionalized population.^3,4

CHSCY was first conducted in 2019 and included 50,000 children and youth ages 1-17 from across Canada’s provinces and territories.³ In 2019, CHSCY was administered as a cross-sectional survey, meaning that respondents were surveyed at a single point in time. In 2023, a longitudinal component was added to the cross-sectional survey, and respondents from the previous cycle (2019) were resurveyed to assess changes in health and well-being over time.⁴ Children and youth ages 5-22 were included in the longitudinal component of the 2023 survey, while children and youth ages 1-17 were included in the cross-sectional component of the 2023 survey.⁴ The 2023 survey included 175,000 respondents (41,923 for the longitudinal component and 133,068 for the cross-sectional component).⁴

The information collected from CHSCY is used by Public Health to produce health indicator reports, which support program planning, evaluation, and policy development, and help to improve awareness of health issues in the community.

Two questionnaires were used to collect survey data. One questionnaire was administered to the Person Most Knowledgeable (PMK) about the selected child or youth aged 1 to 17 (PMK component).⁵ A separate questionnaire was administered directly to the selected youth aged 12 to 17 (youth component).⁵ Youth aged 15 to 17 could be identified as their own PMK if they lived on their own or did not live with a parent.⁵ In these instances, both the PMK and youth components of the survey were completed by the selected youth.⁵ Some modules and questions were not asked of youth who were acting as their own PMK.⁵ Respondents are provided an opportunity to complete the survey questionnaire online. If an e-questionnaire is not completed, a Statistics Canada interviewer calls and asks the respondent to complete the interview by telephone.^3,4

In order for estimates produced from CHSCY data to be representative of the population, and not just the sample itself, weights are applied 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.^3,4

In health indicator reports, comparisons are typically made by sex, age, municipality, income, education, and/or immigration status for questions related to individuals, and by municipality and income for questions related to households. Comparisons are also frequently made between Halton and Ontario since provincial data is available for CHSCY.

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 two 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 but 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 figures and tables.

Bootstrapping techniques are used to produce the coefficient of variation and the 95% confidence intervals.

The income groups are based on household income adjusted for household size. These adjusted incomes for Halton residents are then organized into ten equal groups (deciles), from lowest (quintile 1) to highest (quintile 10), and further categorized as low income (deciles 1-3), middle income (deciles 4-7), and high income (deciles 8-10).

For most indicators related to the health and well-being of the child or youth, education level refers to the highest level of education among the PMK and their spouse. For indicators specifically related to the PMK or their spouse (e.g., mental health of the PMK, mental health of the PMK’s spouse), education level refers to the education of either the PMK or their spouse separately.

Education level is defined as:

• High school or less: respondent has less than a high school diploma or its equivalent; or respondent has a high school diploma or a high school equivalency certificate.
• Trades, college, less than university: respondent has a trades certificate or diploma; or respondent has college/CEGEP/other non-university certificate or diploma; or respondent has a university certificate or diploma below the bachelor’s level.
• Bachelor’s: respondent has a bachelor’s degree (e.g., B.A., B.Sc., L.L.B.).
• Above bachelor’s: respondent has a university certificate, diploma, degree above the bachelor’s level (e.g., master’s degree, PhD).

For most indicators related to the health and well-being of the child or youth, immigrant status refers to the immigration status of the child or youth rather than their parents. For indicators specifically related to the PMK or their spouse (e.g. mental health of the PMK), immigrant status refers to the immigration status of either the PMK or their spouse separately.

Immigrant status is defined as follows.

• Non-immigrant: respondents who are Canadian citizens by birth.
• Immigrant: respondents who are, or who have ever been, landed immigrants or permanent residents. Such persons have been granted the right to live in Canada permanently by immigration authorities. Immigrants who have obtained Canadian citizenship by naturalization are included in this category.
• Non-permanent resident: respondents from another country who have a work or study permit or who are refugee claimants, and their family members are sharing the same permit and living in Canada with them.

CHSCY results are self-reported and may not be recalled accurately. Many survey questions are asked of the PMK and may not accurately reflect the experiences of the child or youth. Excluded from the survey’s coverage are children and youth living on First Nations reserves and other Aboriginal settlements, children and youth living in foster homes, and institutionalized children and youth. The survey is offered in both official Canadian languages (English and French), and individuals who cannot communicate in either language may not complete the survey.

Rounded estimates are used for the presentation of data, and estimates may not total to 100%.

“Don’t know” and “refused” responses are typically excluded from analyses. When “don’t know” is considered a valid response, or when over 5% of respondents answer “don’t know”, the response is included in analyses.

When an estimate is based on a numerator of less than 10 or a denominator of less than 20, the estimate must be suppressed and will not be reported.