Dataset Questions

How is participant death captured in the CLSA?

Participant death is currently captured in three ways: 1) from the next of kin contacting the CLSA directly, 2) through contact with the participants between main waves of data collection, or 3) from linkage to provincial vital statistics. Mortality data are not yet available.

What if there appears to be an error or omission in the data that I receive?

The CLSA takes great care to check the accuracy and completeness of the data prior to release. However, because of the size of the dataset and the large number of variables, we cannot guarantee the accuracy, completeness, or fitness for any particular purpose of the data. It is the responsibility of each data user to verify their dataset, the accompanying data dictionaries and the Data Support Documentation available on our website. If you think your data are incomplete or if you identify errors while conducting your analyses, please contact us at access@clsa-elcv.ca.

Occasionally, there may be a change in the data after you have already received your dataset. If this occurs, we will send a Data Release Update to all approved users, explaining the change(s). You will be able to request the updated dataset if relevant to your study.

How many participants are part of the CLSA at Baseline?

At Baseline, 21,241 participants were enrolled in the Tracking cohort and 30,097 participants in the Comprehensive cohort for a total of 51,338 CLSA participants.

The 30-minute Maintaining Contact Questionnaire (MCQ) interviews with additional health-related questions were completed approximately 18 months after the initial Baseline data collection. In total, 19,052 Tracking participants and 28,789 Comprehensive participants completed the MCQ. The indicator variable ADM_COMPLETE_MCQ is included in the dataset to indicate those participants who completed the MCQ.

What were the Baseline exclusion criteria?

Please refer to Section 5.3 of the CLSA Protocol, available under the Researchers section of our website.

When were Baseline data collected?

Periods of data collection for the Baseline assessments were as follows:

Baseline Tracking: 2011-09 to 2014-05

Baseline Comprehensive: 2011-12 to 2015-07

Maintaining Contact Questionnaire (MCQ) Tracking: 2013-09 to 2016-02

Maintaining Contact Questionnaire (MCQ) Comprehensive: 2014-05 to 2016-01

When were Follow-Up 1 data collected?

Periods of data collection for Follow-Up 1 assessments were as follows:

Follow-up 1 Tracking (telephone): 2014-05 to 2018-12

Follow-up 1 Comprehensive (in home and data collection site): 2015-07 to 2018-12

Does the CLSA provide guidance on how to analyse my data?

No, it is not within the purview of the CLSA to advise approved users on statistical analyses for approved projects. Data Support Documentation is available under the Researchers tab of our website, including a detailed document on the use of Sampling Weights. For further help, please consult with a statistician.

Are bootstrap weights available for the analyses of CLSA data?

No, the CLSA does not have bootstrap weights for the dataset, and we are not planning to produce bootstrap weights in the near future.

Will the CLSA dataset be linked to provincial health administrative databases across Canada? When will these data be available?

CLSA is working centrally on strategies to link individual level CLSA data with data from health administrative databases across Canada. Please continue to monitor the website for updates.

Can I link the CLSA dataset to other third party data holdings that I have access to?

Linking of the CLSA data to third party data holdings by an approved user is prohibited. Any proposals for linkage must be approved by the CLSA Scientific Management Team, and executed internally by the CLSA. Six-digit postal codes or HIN data are never released to users.

Are CLSA data available in Research Data Centres (RDC)?

No, currently, CLSA data are only available through a direct application to the CLSA. For more information on how to apply, please consult the Data Access Application Process section of our website.

What do blank values for a variable represent?

In general, variables in the CLSA dataset reflect the interview process. In some cases, follow-up questions were only asked if specific answers were given to preceding questions. Blank values in the Baseline data represent valid skip patterns. For example, number of daughters and sons are only asked if the participant answered, they have at least one child. In the CLSA dataset, participants with no children will have blank values for both.

What are derived variables?

Within the CLSA dataset, derived variables (DVs) are variables that are created from other variables. DVs are derived by re-grouping or re-classifying the original variables, to glean information otherwise not available. Some DVs are based on published measures or scales. You will find documentation related to DVs on our Data Support Documentation page, under the Researchers tab of our website.