This document-set provides background information on the cognitive testing data collected between November 2015 and the suspension of follow-up activities at the onset of the COVID-19 pandemic in March 2020. It outlines the time frames, testing structure, participation details and key differences compared to the post-2020 follow-up phase. The information here should give most analysts sufficient context to understand how the data were collected and organised.
Pre-2020 Cognitive Testing Narrative.
Pre-2020 cognitive testing details metadata in the format in use at UK LLC.
Pre-2020 cognitive testing summary metadata in the format suitable for use at UK LLC.