Assessment of generalizability, applicability and predictability (GAP) for evaluating external validity in studies of universal family-based prevention of alcohol misuse in young people: Systematic methodological review of randomized controlled trials

1. Fernandez-Hermida, J.R.
2. Calafat, A.
3. Becoña, E.
4. Tsertsvadze, A.
5. Foxcroft, D.R.