Overview

Summary

The purpose of the Childhood National Immunization Coverage Survey (CNICS) is to collect information on national immunization coverage rates for childhood vaccines. CNICS is conducted every two years. The 2021 CNICS is the second iteration of the CNICS to include pregnant women in the sample to estimate the rates of vaccines received during pregnancy. The survey is intended to: determine whether children are vaccinated in accordance with recommended immunization schedules for publicly funded vaccines; determine whether pregnant women are being vaccinated against pertussis (whooping cough) and the flu, which is recommended during pregnancy; provide the World Health Organization and the Pan American Health Organization with estimates of national vaccine coverage for childhood vaccines, such as those against measles, diphtheria, pertussis, tetanus and; polio provide information on parents’ or guardians’ knowledge and beliefs about vaccines.

Childhood vaccinations   
The 2021 CNICS collected information about the vaccines a child received from various sources. The first phase of collection was conducted through a self-response electronic questionnaire or a computer-assisted telephone interview (CATI) during which the person most knowledgeable about the child’s immunizations (PMK) provided information about vaccines the child had received. Parents and guardians of 2- and 14-year-old children were also asked questions regarding their knowledge and beliefs about immunization. In the second phase of collection, respondents were asked to complete and return by mail a form that provides consent for Statistics Canada to contact their child’s immunization providers to obtain their child’s vaccine history. The receipt of the consent form triggered the third phase—the Immunization Record Request form, a mail-out mail-back questionnaire, was sent to the child’s health care providers, who filled out and returned the form with the child’s detailed immunization history. The data from the health care providers were used to enhance the PMK reported data.
The 2021 CNICS asked respondents for permission to access their child’s vaccination record held by regional, provincial and territorial immunization registries. Where available, and where permission was given, the linked data will be used to evaluate the potential to integrate immunization registry data in future cycles of the survey. To access this information, Statistics Canada must have data sharing agreements and data acquisition agreements in place with each individual jurisdiction. So far, Statistics Canada has completed an assessment of the registry coverage for Prince Edward Island and Manitoba (after having put in place data sharing and data acquisition agreements) for childhood vaccination. As a result, parents and guardians living in these two provinces were given the opportunity to skip the detailed questions about vaccination, provided they agreed to share their child’s identifiers with the respective provincial immunization registry. When consent was provided, registry immunization data were used in place of parent or immunization provider data.
The data from one or multiple sources, when available, were used to produce national immunization coverage estimates for 7-year-olds, 14-year-olds (male and female separately) and 17-year-olds, and provincial- or territorial-level results for 2-year-olds.

Vaccination during pregnancy
For the second time in its history, the CNICS surveyed women who had recently given birth to determine whether they were vaccinated against pertussis and influenza during pregnancy. Questions were then asked about the mother’s knowledge and beliefs about the vaccines received during pregnancy, and vaccination in general. Unlike the section of the CNICS that collected data on childhood vaccinations, the section about vaccines received during pregnancy did not ask for the respondent’s consent to allow Statistics Canada to contact their health care providers to obtain their immunization record. They were, however, asked for permission to access their vaccination record held by regional, provincial and territorial immunization registries. Where available, and where permission was given, the linked data will be used to evaluate the potential to integrate these immunization registry data in future cycles of the survey.
     The data from the survey were used to produce national, provincial and territorial (excluding Nunavut which remains included in the national estimates) immunization coverage estimates for vaccines given during pregnancy.

Available Cycles