From the Variables Search, accessed through the DataPreview Portal, full-text searches can be carried out on either the variable Name or Label. The variables can also be filtered by classification through the clickable boxes on the left. To see all of the questionnaires used by the CLSA, you can visit Researcher Resources.
DataPreview Portal Access
Visit the DataPreview Portal to learn more about variables collected from CLSA participants at each wave of data collection. The variable search tool is designed to enable researchers to locate items of interest within available data. Currently, the CLSA DataPreview Portal is only available in English.
Before exploring the DataPreview Portal, please familiarize yourself with the Protocols and Data Availability Tools found below.
Protocols
The CLSA provides documentation online to facilitate understanding of the CLSA platform and how data is gathered and managed.
The study protocols are based on applications the CLSA submits to CIHR for each funding cycle. As the CLSA data collection progresses, occasionally, some measurements are changed. Updated versions of the protocols will be posted as necessary. Please refer to Researcher Resources to review the specific questions and measurements gathered at each phase of the study.
Data Availability
Core data and enhancements to the CLSA
Baseline, Follow-Up 1 and Follow-up 2 data are now available to the research community including:
- Questionnaire data
- Physical assessment data
- Genomics, epigenetics and metabolomics data
- Hematology and biochemistry biomarkers
- Linked environmental data
- Images and raw data
- COVID-19 data
Frequently Asked Questions
Answers to our most frequently asked questions about using the DataPreview Portal.
To obtain all the variables contained in a questionnaire, type the two or three letter prefix (e.g. SDC for Socio-demographic Variables) into the full-text search box in the Variables listing, under “Variable properties > Name”. You can also use more general terms such as ‘food’, ‘work’, etc. (under “Variable properties > Label”) to find variables related to those terms, however, search terms are not exhaustive. For more information on the variables included in a questionnaire, please visit Researcher Resources.
Multiple-choice questions are represented by either a single variable or multiple variables, depending on what the question allows:
– A question allowing only one response is represented by a single variable that can take on multiple values. Open-text responses are permitted in many questions; common and distinct responses are recoded to create new categories within the variable itself.
– For a question allowing multiple responses, each possible response category is assigned its own binary variable. Open-text responses are also permitted in many of these questions; common and distinct options are also recoded to create additional variables within the question scope. The number of variables corresponding to that question matches the number of response options.
In the variable view, clicking on the name of each variable reveals information that is more detailed. For example, under Categories, the variable information page will include the following information:
Name: the value entered for a response in the questionnaire;
Label: the response (or response category) corresponding to each value (Name);
Missing: values corresponding to a question not answered, (don’t know or not applicable, refused).
Clicking on the variable name, in the variable view reveals more detailed information about that variable. (This function is not available for all study variables). This information includes the question pertinent to the variable, the variable label, a list of the response option categories and some automatically generated summary statistics. In some instances, additional notes on skip patterns or references are included as well.