Processes of Change in Preventing Alcohol-Exposed Pregnancy: Replication of a Mediation Analysis

Objective: Further test mechanisms of the CHOICES intervention by replicating analyses of the experiential and behavioral processes of change (POC) for alcohol and for contraception as mediators of the intervention for reducing risk of alcohol-exposed pregnancy (AEP) using data from a more recent trial, CHOICES Plus (CP). Method: As in the prior study, replication models examined indirect paths from intervention to experiential POC for alcohol at 3 months, to behavioral POC at 9 months, to risky drinking and risk of AEP at 9 months and experiential POC for contraception at 3 months, to behavioral POC at 9 months, and to ineffective contraception and risk of AEP at 9 months. To test the temporal relationship, additional models examined the indirect path from behavioral POC for alcohol and POC for contraception at 3 months, to the experiential POC at 9 months, and to risk of AEP at 9 months. A final model tested the mediation of experiential and behavioral POC assessed at 3 months. Results: There was an indirect effect of the intervention on risky drinking (total indirect effect = -.13, 95% confidence interval [CI] [-.32, -.02]) but not AEP via the alcohol POC. There was an indirect effect of the intervention on ineffective contraception (total indirect effect = -.27, 95% CI [-.55, -.07]) and AEP (total indirect effect = -.22, 95% CI [-.46, -.06]) via the contraception POC. Conclusions: This study completely replicated the prior indirect effects of the CHOICES intervention on the targeted risk behaviors through the experiential and behavioral POC for each behavior. Findings support the utility of the POC for informing health behavior change interventions.