A review of expectancy theory and alcohol consumption

Research is reviewed on the association between alcohol outcome expectancie s and consumption which has led many to argue that manipulating expectancie s might be a route to manipulating consumption for problem prevention and t reatment. Studies indirectly and directly evaluating this latter position a re reviewed. Expectancies predicting treatment outcome: two studies have sh own that the more positive expectancies held at treatment, the poorer is tr eatment outcome, but five other studies have failed to find this. Three rel ated studies have shown that the more negative expectancies held at treatme nt, the better the treatment outcome. This evaluation provides evidence inc onsistent with the main position for positive expectancy and limited suppor t for negative. Expectancy manipulations and ad libitum consumption: three studies in the laboratory have shown that increasing positive expectancies through word priming increases subsequent consumption and two studies have shown that increasing negative expectancies decreases it. A single study in the field showed a similar relationship. This evaluation provides evidence consistent with the main position but is limited by measuring consumption changes over only 1-2 hours. Prevention programmes with expectancy componen ts: seven projects are reviewed in which positive expectancies were targete d, bur only two report an expectancy change analysis and in both cases the expectancy change did not relate to subsequent consumption. This evaluation provides evidence inconsistent with the main position. Expectancy challeng e: two related studies are reviewed in which positive expectancy challenges reduce subsequent consumption but changes in expectancy were nor evaluated as predictors of consumption change. Two studies are reviewed which found a reduction in positive expectancy following expectancy challenge bur no re duction in consumption. One study is reviewed in which when negative expect ancy was increased in treatment there was a better treatment outcome at 3 m onths follow-up than when it was not. This evaluation provides evidence inc onsistent with the main position for positive expectancy and limited consis tent evidence for negative. It is concluded that the research has still to be done that securely links expectancy manipulations with subsequent change s in consumption, and fulfils the early promise from association studies.