Comprehension of health-related written materials by older adults

Purpose. This study examined two sets of factors that may affect older adults' comprehension of common health-related written materials. One set was related to text difficulty: the Flesch Reading Ease index and text cohesion. The other set was related to older adults' reading ability: age, education, health conditions, verbal ability (measured by AMNART), working memory (measured by Digits Forward, Digits Backward, and reading span), and health literacy (measured by S-TOFHLA).;Method. 200 short passages that described common senior health issues were collected from websites, health education brochures, and magazines. 16 experiment health passages were selected from the 200 passages based on quartile scores of the Flesch Reading Ease index and text cohesion. Text cohesion was indicated by referential cohesion and latent semantic analysis measures retrieved from the Coh-Metrix software. 124 older adults (Age: M = 77.6; SD = 6.93; Years of education: M = 15.08; SD = 2.94) completed the study and 98% showed adequate health literacy.;Results. Comprehension increased with older adults' working memory (gamma01 = .18, p < .001) and verbal ability (gamma04 = .02, p < .05) but decreased with age (gamma06 = -.01, p = .06). Surprisingly, increasing Flesch Reading Ease impaired comprehension in older adults with working limitations (gamma11 = .06, p < .05). When text cohesion was high, older adults, especially young-old adults, benefited from increasing Flesch Reading Ease. When the text cohesion was low, older adults, especially high verbal older adults and young-old adults, benefited from reducing Flesch Reading Ease (gamma 34 = .007, p < .05; gamma36 = -.006, p < .05, respectively).;Conclusion. Increasing Flesch Reading Ease by using short words or short sentences may result in leaving out connections among ideas and impair older adults' comprehension. Increasing text cohesion by repeating similar words and ideas through out the text may reduce the challenges created by using short words and sentences alone. In a text low in cohesion, the use of long sentences may clarify relationships among ideas or concepts, making the text more comprehensible than one using short sentences. Text cohesion should be included in addition to readability formulas to evaluate text difficulty for older adults.