Abstract
ISSUES: This systematic review of community-based environmental prevention strategies seeks to understand their characteristics, examine their effectiveness and identify challenges for preventing alcohol use among adolescents. APPROACH: A comprehensive search was conducted in MEDLINE/PubMed, Scopus and PsycINFO through December 2024. Eligible studies were randomised or quasi-experimental designs targeting individuals under 21 years, evaluating environmental interventions (regulatory, physical or economic) with outcomes related to underage alcohol consumption and access. Two reviewers independently selected studies, extracted data and assessed risk of bias using the RoB 2 and ROBINS-I tools. KEY FINDINGS: Regulatory strategies were the most frequent (94%; 15/16), followed by physical strategies (37%; 6/16). The most reported outcome was a reduction in alcohol availability (62%; 10/16), followed by a general reduction in consumption (37%; 6/16). Although 69% (11/16) of the studies reported positive effects, heterogeneity in study designs and terminology limited comparability. It is crucial to note that community mobilisation, although not an environmental strategy per se, was described in 81% (13/16) of the studies. IMPLICATIONS: The analysis indicates that the effectiveness and sustainability of environmental interventions are strongly associated with their integration with community mobilisation. This synergy, however, introduces methodological complexity, making it difficult to analyse components in isolation and to standardise evaluation. CONCLUSIONS: The findings reaffirm the value of environmental interventions, particularly regulatory ones, in preventing alcohol use among adolescents. The most promising model is multicomponent, combining actions that modify the environment with robust processes of community participation, forming an adaptable and holistic framework to promote sustainable outcomes.