Understanding the internal and external validity of health literacy interventions: a systematic literature review using the RE-AIM framework.

We conducted a systematic literature review, using the RE-AIM framework, with the goal of determining what information is available to inform research to practice translation of health promotion interventions developed to address health literacy. Thirty-one articles reflecting 25 trials published between 2000 and 2010 met inclusion criteria. Two researchers coded each article, using a validated RE-AIM (reach, effectiveness/efficacy, adoption, implementation, maintenance) data extraction tool, and group meetings were used to gain consensus on discrepancies. Across all studies (14 randomized controlled trials, 11 quasi-experimental; 24 clinic-based, 1 community-based), the mean level of reporting RE-AIM indicators varied by dimension (reach = 69%; efficacy/ effectiveness = 58%; adoption = 36%; implementation = 35%; maintenance = 11%). Among participants enrolled in the 25 interventions, approximately 38% were identified as low health literate. Only eight of the studies examined health literacy status as a moderator of intervention effectiveness. This review suggests that the current research on health promotion for participants with low health literacy provides insufficient information to conclude whether interventions for health literacy can attract the target population, achieve an effect that is sustainable, or be generalized outside of clinical settings. Recommendations for enhancing the design and reporting of these trials are provided.