Lack of a priori specification and inconsistent approaches to creating health literacy and numeracy levels or thresholds in analyses, hampering comparisons between studies.
Inconsistent choices of potential confounding variables in multivariate analyses.
Small sample sizes, making it impossible for us to determine whether null findings represented a true lack of effect or simply limitations in statistical power.
Studies in just one clinic or in other narrowly defined patient populations, rendering the applicability of findings to other settings or populations unknowable.
Use of health literacy tools that continue to focus primarily on reading ability.
The limited number of studies examining potential mediators of health literacy, such as self-efficacy, knowledge, or beliefs.
Few studies examining the role of health literacy on health disparities.
No studies examining differences in outcomes related to oral literacy skills.