Survey on Accessible Print Materials (SAPM)

Detailed information for 2023




One Time

Record number:


The Survey on Accessible Print Materials gathers (SAPM) information from Canadians who require printed works in alternate formats. The survey aims to understand their requirements for and use of these formats, and the barriers they encounter in obtaining them. Printed works can include books, newspapers, magazines and other reading materials that a person may read for leisure, education or work.

Data release - June 22, 2023; October 3, 2023 (Exploring the experiences of Canadians accessing alternate format print materials)


Information from this survey will be used to support the development of programs to improve access to reading materials in alternate formats, such as braille, e-braille, large print, accessible e-books and audiobooks.


  • Disability
  • Health

Data sources and methodology

Instrument design

The questionnaire was developed in collaboration with Employment and Social Development Canada (ESDC). The EQ application underwent qualitative testing by QDRC in conjunction with the Centre of Expertise in Accessibility (CEA).


This is a sample survey with a cross-sectional design.

The sample design is a stratified two-phase design based on the 2021 Census. The first phase is the Census itself, and corresponds to the sample of households selected to receive the long form (about one household out of four, systematically selected across Canada). Phase 2 corresponds to the sample of persons who reported having difficulty on the Activities of Daily Living questions on the long form Census.

Sampling unit
The sampling unit for phase 1 (the Census) is the household, while that of phase 2 is the person.

Stratification method
Strata are defined so as to guarantee sufficient sample sizes in each domain of estimation and optimize sample allocation. The domains of estimation consist of the following age groups: 15 to 19, 20 to 24, 25 to 34, 35 to 44, 45 to 54, 55 to 64 and 65 and over.

Sampling and sub-sampling
The total sample size for SAPM was 10,000 persons.

In order to obtain quality estimates for each age group of interest as well as at the national level, a Kish allocation was used to allocate the sample between the strata.

Systematic sampling was used within each stratum, after sorting the frame by collection unit, to reduce the possibility of sampling more than one person per household.

Data sources

Data collection for this reference period: 2023-03-15 to 2023-04-15

Responding to this survey is voluntary.

Data are collected directly from survey respondents.

Data are collected directly from survey respondents either through an electronic questionnaire or through computer assisted telephone interviewing.

View the Questionnaire(s) and reporting guide(s) .

Error detection

Electronic files containing the daily transmissions of completed respondent survey records were combined to create the "raw" survey file. Before further processing, verification was performed to identify and eliminate potential duplicate records and to drop non-response and out-of-scope records.

In addition, some out-of-scope respondent records were found during the data clean-up stage. All respondent records that were determined to be out-of-scope and those records that contained no data were removed from the data file.

After the verification stage, editing was performed to identify errors and modify affected data at the individual variable level. The first editing step was to identify errors and determine which items from the survey output needed to be kept on the survey master file. Subsequent to this, invalid characters were deleted and the remaining data items were formatted appropriately.


This methodology type does not apply to this statistical program.


The estimation of population characteristics from a sample survey is based on the premise that each person in the sample represents a certain number of other persons in addition to themselves. This number is referred to as the survey weight. The process of computing survey weights for each survey respondent involves several steps.

1) Each selected respondent is given an initial weight equal to the inverse of its selection probability from the sampling frame (the census). Respondents identified as out-of-scope for reasons such as deceased, moved outside Canada or living in an institution during collection are dropped from the sample.

2) The weights of the respondents and out-of-scope units due to not having not having a difficulty with print material are then adjusted to take into account non-response. Adjustments are made based on the age group, as well as other auxiliary information such as marital status and education level. Since individuals who do not have a difficulty with print material represent a significant portion of the respondents, and no calibration totals are available for the population of individuals with a print disability, this type of out-of-scopes was kept during the non-response adjustment phase to account for non-respondents who would be in fact out-of-scopes.

3) Drop the out-of-scope units that were kept at step 2.

Variance estimation is based on a re-sampling method called bootstrap estimation.

The Generalized Estimation System from Statistics Canada (G-Est) was used to generate the survey weights and bootstrap weights.

Quality evaluation

While rigorous quality assurance mechanisms are applied at all stages of the statistical process, the validation and detailed review of data by statisticians is the ultimate verification of quality prior to release. Many validation measures were implemented, they include:

a. Verification of estimates through cross-tabulations
b. Consultation with stakeholders internal to Statistics Canada
c. Consultation with external stakeholders

Disclosure control

Statistics Canada is prohibited by law from releasing any information it collects that could identify any person, business, or organization, unless consent has been given by the respondent or as permitted by the Statistics Act. Various confidentiality rules are applied to all data that are released or published to prevent the publication or disclosure of any information deemed confidential. If necessary, data are suppressed to prevent direct or residual disclosure of identifiable data.

Revisions and seasonal adjustment

This methodology type does not apply to this survey.

Data accuracy

Survey errors come from a variety of different sources. One dimension of survey error is sampling error. Sampling error is defined as the error that arises because an estimate is based on a sample rather than the entire population. Sampling error can be expressed through a confidence interval (CI) or coefficient of variation (CV).

Non sampling error:
Non-sampling errors can be defined as errors arising during the course of virtually all survey activities, apart from sampling. These include coverage errors, non-response errors, response errors, interviewer errors, coding errors, and other types of processing errors.

Coverage errors occur when there are differences between the target population and the sampled population (or survey population). Because the SAPM sample was selected from those who reported having difficulty on the Activities of Daily Living (ADL) questions on the 2021 long form Census, individuals who have difficulty with print materials but did not report having difficulty on one of the ADL questions could not be sampled for SAPM, resulting in undercoverage. If this group of individuals is significantly different than those who reported having difficulty on the ADL questions with respect to the characteristics measured in the SAPM, a bias could be introduced. In addition, due to the passage of time since the 2021 census, the SAPM frame will be subject to additional undercoverage due to "births" (persons who did not experience difficulty with print materials at the time of census 2021, but developed difficulty since; immigration). Undercoverage on the frame could lead to underrepresentation of the target population and bias the results. Similarly, the SAPM frame will also be subject to overcoverage due to "deaths" (emigration, deaths, those who do not experience difficulty with print material anymore (for example following an eye surgery)). The impact of overcoverage on the frame is reduced, as this can be determined at the time of collection for resolved units, however some overcoverage may remain for the unresolved units and for those not selected in the sample. Estimates of under and over coverage are not available for the SAPM. To the extent that the survey frame does not align with the target population, there could be bias in the estimates. Users should take this into account when using the SAPM data to make inferences on the target population.

Non-response is both a source of non-sampling error and sampling error. Non-response results from a failure to collect complete information from all units in the selected sample. Non-response is a source of non-sampling error in the sense that non-respondents often have different characteristics from respondents, which can result in biased survey estimates if non-response bias is not fully eliminated through weighting adjustments. The lower the response rate, the higher the risk of bias. The response rate for the SAPM was 49.8%. Attempts were made to reduce the potential nonresponse bias as much as possible through weighting adjustments.

Measurement errors occur when the response provided differs from the real value. Such errors may be attributable to the respondent, the interviewer, the questionnaire or the collection method, for example. For the SAPM, every effort was made to develop questions that would be understandable, relevant and appropriate for respondents. Other measures were also taken, including the use of skilled interviewers, extensive training of interviewers, and observation and monitoring of interviewers. Processing errors may occur at various stages, including data capture, coding and editing. Quality control procedures were applied at every stage of data processing to reduce this type of error.

Sampling error:
Sampling error is defined as the error that arises because an estimate is based on a sample rather than the entire population. The sampling error for the SAPM is reported through 95% confidence intervals. The 95% confidence interval of an estimate means that if the survey were repeated over and over again, then 95% of the time (or 19 times out of 20), the confidence interval would cover the true population value. Estimates and confidence intervals flagged with the letter F do not meet Statistics Canada's quality standards, and are suppressed.

Coverage error:
Coverage errors arise when there are differences between the target population and the observed population. The target population is comprised of all the individuals having difficulty with print materials. The survey frame is individuals who reported having difficulty on the Activities of Daily Living questions on the long form Census. To the extent that the excluded population differs from the rest of the target population, the results may be biased.

Report a problem on this page

Is something not working? Is there information outdated? Can't find what you're looking for?

Please contact us and let us know how we can help you.

Privacy notice

Date modified: