Efficacy of an appearance-based and a health-based sun protection intervention on summer vacationers' behaviours, PRISME cluster randomized crossover trial, France.

OBJECTIVES: Sun-seeking vacationers are particularly vulnerable to melanoma. Appearance-based interventions (ABi) showing skin damage of ultraviolet exposure may be a promising prevention tool to improve skin protection. This study aimed to measure and compare the efficacy of an ABi and a health-based intervention (HBi) on French summer vacationers' behaviours and to identify differences between subpopulations. DESIGN: A cluster randomized crossover trial with three intervention groups (control, ABi, HBi) was conducted in eight campsites on the French Mediterranean coast in summer 2019. METHODS: 1355 vacationers of both sexes and aged 12-55 years were included and followed up after 4 days (T1) and 14 months (T2). Efficacy of interventions was evaluated using multilevel mixed-effect models comparing groups on three outcomes: self-reported sun protection behaviours, sunbathing and skin colour measures. Protection behaviours were analysed according to subpopulations. RESULTS: Compared to controls, the ABi group had a higher protection and sunbathed for fewer hours at T1 and T2. In the HBi group, the skin colour was lighter than controls at T1. When comparing ABi to HBi, ABi participants had lower exposure than HBi at T1 and T2. The protection of people with a 3-years university degree was higher in the HBi group than in others groups while that of people with a secondary school certificate was higher in the ABi group. CONCLUSIONS: Our study provides further evidence of individual sun protection interventions effect in a touristic setting and highlights the relevance of ABi messages to supplement HBi messages, particularly in certain subpopulations with low to intermediate education levels.

Influence of Social and Psychosocial Factors on Summer Vacationers' Sun Protection Behaviors, the PRISME Study, France.

Objectives: Summer intermittent sun exposure is a major risk factor for melanoma. Socioeconomic position, cognitive and psychosocial factors play a role in sun protection behaviors but the underlying mechanisms are unknown. This study aimed to measure the influence of educational level on sun protection behaviors in French summer vacationers on the Mediterranean coastline, and to identify the mediating psychosocial factors in this pathway. Methods: In summer 2019, French vacationers aged 12-55 staying in coastline campsites were asked about their holiday sun protection behaviors, their knowledge, attitudes, perceived control, and social norm relative to sun protection. A structural equation model measured the direct and indirect effects of educational level on protection behaviors via cognitive and psychosocial factors. Results: Sun protection during vacation increased with educational level. Theoretical knowledge partially mediated this association, from 22% to 86%, particularly for intermediate educational levels. Conclusion: Our results highlight the importance of implementing suitable sun prevention interventions for vacationers, especially those with a lower socioeconomic position. Improving theoretical knowledge around sun protection may be an important part of broader efforts to encouraging improved preventive behaviors.

Effect of an Appearance-Based vs. a Health-Based Sun-Protective Intervention on French Summer Tourists' Behaviors in a Cluster Randomized Crossover Trial: The PRISME Protocol.

Background: Sun exposure has short- and long-term adverse effects on eyes, skin, and the immune system. The most serious effect, melanoma, is largely attributable to natural ultraviolet radiation. Its prevalence is steadily increasing in fair-skinned populations in most European countries. Despite annual prevention campaigns, the French population continues to be overexposed to the sun and under-protected. Social and psychosocial characteristics may play an important role in sun protection determinants. Overexposure is partially motivated by a desire to tan oneself for aesthetic reasons. During summer, intense exposure constitutes a major risk factor for melanoma, making tourists a particularly high-risk population. Literature reviews concluded that appearance-based interventions highlighting the aesthetic effects of sun exposure on skin photoaging showed promise in terms of improving sun-exposure and sun-protection behaviors, especially among younger people, but that more rigorous studies were needed. In this context, we implemented the PRISME study to: - identify the determinants, in particular social and psychosocial, of sun-protection of French summer tourists visiting the Mediterranean coastline; - design two prevention interventions grounded in psychosocial theories; - compare the impact of both interventions on tourists' sun-protection behaviors, and identify the determinants influencing this impact. This paper presents the methodology of the PRISME study. Methods: During summer 2019, we conducted a cluster randomized crossover trial to compare two prevention interventions, one based on health-related messages (health effects information, phototype calculation), the other on appearance-related messages (photoaging information, ultraviolet photography), among French tourists aged 12-55 years old in coastline campsites in the French region of Occitanie. Both interventions were anchored in the theory of planned behavior and in the transtheoretical model. The interventions' impact was measured using face-to-face questionnaires and skin color measurements both immediately before and 4 days after the interventions. A second follow-up, using an online questionnaire, will be conducted in September 2020 to measure the longer-term effects of both interventions. Discussion: Despite certain study limitations, PRISME take into consideration several known methodological gaps. The study's results will enable to evaluate the efficacy of the promising appearance-based approach in France, and to identify vulnerable sub-populations and mechanisms to improve sun-protection behaviors of French tourists.