Readability of Online Patient Educational Materials for Coronary Artery Calcium Scans and Implications for Health Disparities

Abstract

Background Coronary artery calcium (CAC) scans can help reclassify risk and guide patient-clinician shared treatment decisions for cardiovascular disease prevention. Patients increasingly access online patient educational materials (OPEMs) to guide medical decision-making. The American Medical Association (AMA) recommends that OPEMs should be written below a 6th-grade reading level. This study estimated the readability of commonly accessed OPEMs on CAC scans. Methods and Results The terms "coronary artery calcium scan," "heart scan," and "CAC score" were queried using an online search engine to identify the top 50 commonly accessed websites based on order of search results on December 17, 2019. Grade-level readability was calculated using generalized estimating equations, with observations nested within readability metrics from each website. Results were compared with AMA-recommended readability parameters. Overall grade-level readability among all search terms was 10.9 (95% CI, 9.3-12.5). Average grade-level readability of OPEMs for the search terms "coronary artery calcium scan," "heart scan," and "CAC score," was 10.7 (95% CI, 9.0-12.5), 10.5 (95% CI, 8.9-12.1), and 11.9 (95% CI, 10.3-13.5), respectively. Professional society and news/media/blog websites had the highest average reading grade level of 12.6, while health system websites had the lowest average reading grade level of 10.0. Less than half of the unique websites (45.3%) included explanatory images or videos. Conclusions Current OPEMs on CAC scans are written at a higher reading level than recommended for the general public. This may lead to patient misunderstanding, which could exacerbate disparities in cardiovascular health among groups with lower health literacy.

Keywords: coronary artery calcium; health literacy; online patient educational material.

Figure 1. Data refinement.

An initial query of the first 50 results for each of the 3 search terms “coronary artery calcium scan,” “heart scan,” and “CAC score” provided a total of 150 results. We excluded 25 nonpatient‐directed materials, yielding 125 coronary artery calcium (CAC) online patient educational materials (OPEMs). Of these 125 OPEMs, 95 were unique results with no overlap among search terms.

Figure 2. Average grade‐level readability of the top 50 online patient educational materials (OPEMs) for the “coronary artery calcium scan” search term.

Point (blue) and interval (black) estimates display average grade‐level readability with 95% CIs of the 5 readability metrics for each unique OPEM. Full website titles are listed in Table S1. OPEMs are organized by increasing grade level. All OPEMs surpassed the American Medical Association (AMA)–recommended readability parameters for online health information (6th‐grade reading level depicted by a vertical red line) except for WebMD, which had the lowest average grade‐level readability of 6.2 (CI, 4.7–7.7).

Figure 3. Average grade‐level readability with 95% CIs for each website category.

Each circle represents a readability score for 1 online patient educational material (OPEM); there are 5 mean readability scores for each unique OPEM. Governmental and health system websites had the lowest average reading grade levels of 10.2 and 10.0, respectively. News/media/blog and professional society websites both had an average reading grade level of 12.6. Websites in the unspecified category had the highest average reading grade level of 12.1. The lower bounds of the 95% CIs for all categories exceed the American Medical Association–recommended 6th‐grade level.