Empirical relationships between health literacy and treatment decision making: A scoping review of the literature

OBJECTIVES: This study asked: What is known from the existing literature about the empirical relationships between health literacy (HL) and the three stages of the treatment decision making (TDM) process: information exchange, deliberation, and deciding on the treatment to implement? METHODS: A scoping review of the literature was conducted. Four databases were searched and a total of 2772 records were returned. After de-duplication and three levels of relevance screening, 41 primary studies were included. RESULTS: Relationships between HL and information exchange were studied more often than relationships between HL and deliberation and deciding on the treatment to implement. Across the 41 studies, there was little overlap in terms the measure(s) of HL adopted, the aspect of TDM considered, and the characteristics of the study populations--making comparisons of the findings difficult. Multiple knowledge gaps and measurement-related problems were identified; including, the possibility that the process of TDM influences HL. CONCLUSION: The importance of HL to the three stages of TDM is unclear because of the knowledge gaps and measurement-related problems that exist. PRACTICE IMPLICATIONS: There are many uncertainties about how TDM, or the design and use of patient decision aids, should respond to patients with different levels of HL.