A systematic review and meta-analysis of English language online patient education materials in breast cancer: Is readability the only story?

Background: Online patient education materials (OPEMs) are an increasingly popular resource for women seeking information about breast cancer. The AMA recommends written patient material to be at or below a 6th grade level to meet the general public's health literacy. Metrics such as quality, understandability, and actionability also heavily influence the usability of health information, and thus should be evaluated alongside readability. Purpose: A systematic review and meta-analysis was conducted to determine: 1) Average readability scores and reporting methodologies of breast cancer readability studies; and 2) Inclusion frequency of additional health literacy-associated metrics. Materials and methods: A registered systematic review and meta-analysis was conducted in Ovid MEDLINE, Web of Science, Embase.com, CENTRAL via Ovid, and ClinicalTrials.gov in June 2022 in adherence with the PRISMA 2020 statement. Eligible studies performed readability analyses on English-language breast cancer-related OPEMs. Study characteristics, readability data, and reporting of non-readability health literacy metrics were extracted. Meta-analysis estimates were derived from generalized linear mixed modeling. Results: The meta-analysis included 30 studies yielding 4462 OPEMs. Overall, average readability was 11.81 (95% CI [11.14, 12.49]), with a significant difference (p < 0.001) when grouped by OPEM categories. Commercial organizations had the highest average readability at 12.2 [11.3,13.0]; non-profit organizations had one of the lowest at 11.3 [10.6,12.0]. Readability also varied by index, with New Fog, Lexile, and FORCAST having the lowest average scores (9.4 [8.6, 10.3], 10.4 [10.0, 10.8], and 10.7 [10.2, 11.1], respectively). Only 57% of studies calculated average readability with more than two indices. Only 60% of studies assessed other OPEM metrics associated with health literacy. Conclusion: Average readability of breast cancer OPEMs is nearly double the AMA's recommended 6th grade level. Readability and other health literacy-associated metrics are inconsistently reported in the current literature. Standardization of future readability studies, with a focus on holistic evaluation of patient materials, may aid shared decision-making and be critical to increased screening rates and breast cancer awareness.