Health Literacy Interventions in Cancer: a Systematic Review.

Approximately one-third of adults in the United States (U.S.) have limited health literacy. Those with limited health literacy often have difficultly navigating the health care environment, including navigating care across the cancer continuum (e.g., prevention, screening, diagnosis, treatment). Evidence-based interventions to assist adults with limited health literacy improve health outcomes; however, little is known about health literacy interventions in the context of cancer and their impact on cancer-specific health outcomes. The purpose of this review was to identify and characterize the literature on health literacy interventions across the cancer care continuum. Specifically, our aim was to review the strength of evidence, outcomes assessed, and intervention modalities within the existing literature reporting health literacy interventions in cancer. Our search yielded 1036 records (prevention/screening n = 174; diagnosis/treatment n = 862). Following deduplication and review for inclusion criteria, we analyzed 87 records of intervention studies reporting health literacy outcomes, including 45 pilot studies (prevention/screening n = 24; diagnosis/treatment n = 21) and 42 randomized controlled trials or quasi-experimental trials (prevention/screening n = 31; diagnosis/treatment n = 11). This literature included 36 unique interventions (prevention/screening n = 28; diagnosis/treatment n = 8), mostly in the formative stages of intervention development, with few assessments of evidence-based interventions. These gaps in the literature necessitate further research in the development and implementation of evidence-based health literacy interventions to improve cancer outcomes.