Disentangling the temporal relationship between alcohol-related attitudes and heavy episodic drinking in adolescents within a randomized controlled trial.

Background And Aims: Within many alcohol prevention interventions, changes in alcohol-related attitudes (ARA) are often proposed as precursors to changes in drinking behaviour. This study aimed to measure the longitudinal relationship between ARA and behaviour during the implementation of a large-scale prevention trial.

Design And Setting: This study was a two-arm school-based clustered randomized controlled trial. A total of 105 schools in Northern Ireland and Scotland participated in the Steps Towards Alcohol Misuse Prevention Programme (STAMPP) Trial.

Participants: A sample of 12 738 pupils (50% female; mean age = 12.5 years at baseline) self-completed questionnaires on four occasions (T1-T4). The final data sweep (T4) was 33 months post baseline.

Measurements: Individual assessments of ARA and heavy episodic drinking (HED) were made at each time-point. Additional covariates included location, school type, school socio-economic status and intervention arm. Estimated models examined the within-individual autoregressive and cross-lagged effects between ARA and HED across the four time-points (Bayes estimator).

Findings: All autoregressive effects were statistically significant for both ARA and HED across all time-points. Past ARA predicted future ARA [e.g. ARA → ARA = 0.071, credibility interval (CI) = 0.043-0.099, P < 0.001, one-tailed]. Similarly, past HED predicated future HED (e.g. HED → HED = 0.303, CI = 0.222-0.382, P < 0.001, one-tailed). Autoregressive effects for HED were larger than those for ARA at all time-points. In the cross-lagged effects, past HED statistically significantly predicted more positive ARA in the future (e.g. HED → ARA = 0.125, CI = 0.078-0.173, P < 0.001, one tailed) except for the initial T1-T2 path. In contrast, past ARA did not predict future HED across any time-points.

Conclusions: Changes in alcohol-related attitudes were not a precursor to changes in heavy episodic drinking within the Steps Towards Alcohol Misuse Prevention Programme (STAMPP) Trial in Scotland and Northern Ireland. Rather, alcohol-related attitudes were more likely to reflect prior drinking status than predict future status. Heavy episodic drinking status appears to have a greater impact on future alcohol attitudes than attitudes do on future heavy episodic drinking.