Data Collection

Click image below to view full-sized version

Among the more than 51,000 participants in the study, data are collected from more than 21,000 people through telephone interviews, referred to as the Tracking assessment. The remaining 30,000+ participants provide data through in-home interviews and data collection site visits, referred to as the Comprehensive assessment. All participants were also contacted by telephone 18 months after each full telephone or in-home interview to complete the Maintaining Contact Questionnaire (MCQ), which included some additional data collection.

Data Collection Tools

Below are links to all of the questionnaires used by CLSA since it began data collection in 2011. 


Telephone interview - (60 minutes, data collected from September 2011 to May 2014)
Telephone interview - (30 minutes, data collected from September 2013 to December 2015)
In-home, face-to-face interview - (90 minutes, data collected from May 2012 to May 2015)
Data Collection Site visit interview - (2.5 hours, May 2012 to May 2015, including Contraindications, Neuropsychological Battery and Disease Symptoms)

Follow-up 1

At this stage of the study, all of the data collection that was part of the MCQ during baseline was merged into the full telephone and in-home interviews.

Telephone interview - (100 minutes, data collected from December 2015 to December 2018)
In-home. face-to-face interview  - (100 minutes, data collected from July 2015 to July 2018)
Data Collection Site visit questionnaire - (2.5 hours, July 2015 to July 2018)

For a list of physical assessments conducted at the DCS, click here.

Follow-up 2

Telephone interview
In-home, face-to-face interview
Data Collection Site visit questionnaire