Abstract
OBJECTIVE: Predictive and external validity was studied among cluster profiles for sun protection behavior within stages from Transtheoretical Model of behavior change using follow-up data. METHODS: Data from participants in a home-based expert system were analyzed. Longitudinal patterns of clusters on the precontemplation, contemplation, and preparation stages of change were assessed. Differences between clusters on membership in action/maintenance stages and scores on the Sun Protection Behavior Scale (SPBS) were measured at 12 and 24 months after intervention. RESULTS: Differences between clusters on stage progression and on scores from the SPBS were found at 12 and 24 months after intervention at all stages. DISCUSSION: Predictive and external validity of sun protection subtypes was established using sun protection variables after a stage-matched intervention. Results provide information to improve interventions for sun protection.