Processing fluency effect of a leaflet for breast and cervical cancer screening: a randomized controlled study in Japan.

Processing fluency (the inferred subjective ease with which people process information) has been a topic of increasing research attention in the field of psychology over the past decade. We examined the effect of improving written materials in terms of processing fluency with regard to encouragement for obtaining breast and cervical cancer screening. We randomly assigned 670 women to intervention or control conditions; the 215 who mailed back distributed questionnaires were the study participants. A standard leaflet for cancer screening was mailed to the control group, while the materials mailed to the intervention group were improved in terms of perceptual fluency (e.g., legibility), linguistic fluency (e.g., readability), retrieval fluency (e.g., reducing amount of information) and imagery fluency (having recipients imagine future behavior and events). The screening rate of the intervention group was significantly higher than that of the control group (29.4% vs. 14.2%, χ2  = 7.275, df = 1, p = .007, φ = .184). Improving the processing fluency of written materials may be useful for encouraging individuals to obtain breast and cervical cancer screening.