The most important implication, however, of the findings of this study is the need to develop a very underdeveloped literature in order to support evidence-based prevention practice. Apart from the early study by Pedersen and Skrondal with weak control for confounding,18 the existence of effects of AFD on adult drinking and related problems is supported, but not at all strongly in the first study by Guttmannova et al.20 The opposite possibility is supported by the second study from that cohort, and those by Rossow and Kuntsche and Warner and White.19 21 22 This rather mixed evidence available from the aforementioned studies, and also the strong likelihood of publication bias indicates the need for caution in making inferences about any such effects. The most sensible conclusions are that we do not yet know whether starting drinking earlier leads to adult alcohol problems and that we need to develop our understanding of drinking behaviour, across the life course and across the globe. What is already known on this subjectA proposed relationship between an early onset of drinking and alcohol problems in adulthood
