Insights into the concept and measurement of health literacy from a study of shared decision-making in a low literacy population.

This article explores the concept and measurement of health literacy in the context of shared health decision-making. It draws upon a series of qualitative and quantitative studies undertaken in the development and evaluation of a bowel cancer screening decision aid for low literacy populations. The findings indicate that different types of health literacy (functional, interactive and critical) are required in decision-making and present a set of instruments to assess and discriminate between higher level health literacy skills required for engagement in decision-making. It concludes that greater sophistication in both the definition and measurement of health literacy in research is needed.