Study design feature | Prospective cohort | Retrospective cohort | Nested case-control |
---|---|---|---|
(1) A comparison between two or more groups of participants with different levels or patterns of alcohol consumption (‘yes’ = cohort or NCC) | Yes | Yes | Yes |
(2a) Participants were allocated to groups based on different levels or patterns of alcohol exposure | Yes | Yes | No (based on outcome) |
(2b) Participants were allocated to groups on the basis of outcomes | No | No | Yes |
(3) The following parts of the study were prospective: | Â | Â | Â |
a. Identification of participants | Yes | No | Yes |
b. Assessment of alcohol consumption and allocation to alcohol consumption categories prior to follow-up measures of cognition | Yes | No | Yes (from existing records) |
c. Assessment of outcomes (baseline cognition) | Yes | Possibly | Yes |
d. Generation of hypotheses | Yes | Yes | Yes |
Assessment of comparability of groups was based on: | Â | Â | Â |
• Potential confounders | Possibly | Possibly | Possibly |
• Outcome variables at baseline | Possibly | Possibly | No |