Extracted information	Included details
General information	Author, title, source, publication date, language, related or duplicate publications
Source of data	Cohort (retrospective or prospective data collection), case‐control, randomised trial, or secondary analysis of registry data
Participant information	Participant eligibility and recruitment method (e.g. consecutive or other recruitment, number of centres, inclusion and exclusion criteria); participant demographics (e.g. age, sex); details of ongoing treatments/medications; study dates; country of recruitment; setting (using our definitions of primary, secondary, and community settings)
Prognostic factor	Definition and method of measurement of prognostic factor. We do not expect duration of exposure (pre‐ or post‐study commencement) to be regularly recorded; however, where possible, we will record timing of prognostic factor measurement (number of weeks participants have been on the ACB drugs prior to baseline assessment); where data are available we will also collect duration of exposure during the study.
Outcomes to be predicted	Definition and method of measurement of outcome; time of outcome ascertainment, or summary of duration of follow‐up, overall survival, and dementia‐free survival
Adjustment for other prognostic factors (covariates)	List of all the covariates that were adjusted for in any regression model
Sample size	Number of participants and number of outcomes/events; how missing data were handled (e.g. complete‐case analysis, imputation, or other methods)
Reported results	We will record incidence of dementia and cognitive decline. Data on incident dementia are likely to be in the form of hazard ratios. Where possible, we will extract estimates and corresponding confidence intervals from each included paper. Change in validated cognitive assessment data may be presented as continuous data or as events with hazard ratios (e.g. time till cognitive score declines below a particular value). We will also record overall survival (including duration of follow‐up) and dementia‐free survival (including duration of follow‐up).