Our research investigated how individual differences and text features interact to predict comprehension of health-related texts. We found that younger, more educated, health-literate, and proficient participants were more likely to understand health-related texts than older, low proficiency, less educated and health literate individuals. Text features did not predict comprehension.
Background. Problems with understanding health-related documents are common (e.g., Cortez, et al., 2015). However, relatively little attention has focused on how the effects of cognitive abilities, and the effects of linguistic properties of the text, predict reading comprehension of health-related information. Critically, research evidence indicates that different texts are understood differently by different people (e.g., Francis et al., 2018; Liu et al., 2009). We investigated how individual differences and text features interact to predict comprehension of health-related texts. Method. First, we analysed a sample of health-related texts to obtain estimates of linguistic predictors, such as average sentence length, word frequency, and text coherence of these texts. We also obtained readability estimates of these texts, as measured using two readability formulae, specifically the Flesch Reading Ease (Flesch, 1948), and the Coh-Metrix L2 Readability Index (Crossley et al., 2008). Second, we tested the accuracy of responses made by 200 individuals to questions probing comprehension of a sample of health-related texts. We measured variation among the participants in their cognitive abilities to capture individual differences. Last, we ran Bayesian mixed-effects models to examine how the effects of reader attributes and textual characteristics interact in predicting comprehension of health-related information. Results. We found that older individuals were less likely to understand health-related texts than younger individuals. In turn, the more educated, health literate, and highly proficient English language speakers, were more likely to understand health-related texts than the less educated, health literacy, and proficient counterparts. Variation in text features, including readability formulae, did not predict comprehension of health-related texts. Discussion. Our findings suggest that the utility of designing health-related texts with the aid of readability formulae is likely to be limited. However, improving health literacy and English language proficiency could improve comprehension of health-texts.
