Murmurs are abnormal audible heart sounds produced by turbulent blood flow. Therefore, murmurs in a child may be a source of anxiety for family members. Families often use online materials to explore possible reasons for these murmurs, given the accessibility of information on the Internet. In this study, we evaluated the quality, understandability, readability, and popularity of online materials about heart murmur.

An Internet search was performed for “heart murmur” using the Google search engine. The global quality score (on a scale of 1 to 5, corresponding to poor to excellent quality) and Health on the Net code were used to measure the quality of information presented. The understandability of the web pages identified was measured using the Patient Education Materials Assessment Tool (score range from 0 to 100%, scores below 70% reflect poor performance). The readability of each web pages was assessed using four validated indices: the Flesch Reading Ease Score, the Flesch–Kincaid Grade Level, the Gunning Frequency of Gobbledygook, and the Simple Measure of Gobbledygook. The ALEXA traffic tool was used to reference domains’ popularity and visibility.

We identified 230 English-language patient educational materials that discussed heart murmur. After exclusion, a total of 86 web pages were evaluated for this study. The average global quality score was 4.34 (SD = 0.71; range from 3 to 5) indicating that the quality of information of most websites was good. Only 14 (16.3%) websites had Health on the Net certification. The mean understandability score for all Internet-based patient educational materials was 74.6% (SD = 12.8%; range from 31.2 to 93.7%). A score suggesting these Internet-based patient educational materials were “easy to understand”. The mean readability levels of all patient educational materials were higher than the recommended sixth-grade reading level, according to all indices applied. This means that the level of readability is difficult. The average grade level for all web pages was 10.4 ± 1.65 (range from 7.53 to 14.13). The Flesch–Kincaid Grade level was 10 ± 1.81, the Gunning Frequency of Gobbledygook level was 12.1 ± 1.85, and the Simple Measure of Gobbledygook level was 9.1 ± 1.38. The average Flesch Reading Ease Score was 55 ± 9.1 (range from 32.4 to 72.9).

We demonstrated that web pages describing heart murmurs were understandable and high quality. However, the readability level of the websites was above the recommended sixth-grade reading level. Readability of written materials from online sources need to be improved. However, care must be taken to ensure that the information of web pages is of a high quality and understandable.