We also learned many new things about interventions to mitigate the effect of low health literacy. First, we identified several design features of interventions that were effective in one or a few studies ; they all warrant further study in broader populations. Second, interventions focused on a broader range of outcomes, allowing us to make inferences about effect across outcomes. Interventions are effective to mitigate the effects of low health literacy may work by increasing knowledge and self-efficacy or by changing behavior.