Readability of health related quality of life instruments in urology

Purpose: The average American adult reads at a fifth to eighth-grade level, with wide variability, presenting challenges for the assessment of self-reported health related quality of life. We identified the health related quality of life instruments used in patients with urological diseases and evaluated their readability.

Materials and methods: We focused on the most burdensome urological diseases, based on total expenditures in the United States. We then identified disease specific instruments by systematically searching PubMed, the Cochrane Database of Systematic Reviews, Google, Google Scholar, the Patient Reported Outcome and Quality of Life Instruments Database (Mapi Research Institute, Lyon, France) and Yahoo! for health related quality of life studies in patients with these urological conditions. Where disease specific instruments were lacking, we noted the general health related quality of life measures most commonly used. For each instrument, we calculated the median Flesch-Kincaid grade level, the proportion of questionnaire items below an eighth-grade reading level, the mean Flesch Reading Ease, and the mean number of words per sentence and characters per word, all of which are validated measures of readability.

Results: The average +/- SD of the median Flesh-Kincaid reading levels was 6.5 +/- 2.1 (range 1.0 to 12.0). Of the 76 instruments 61 (80%) were at or below an eighth-grade reading level. The mean reading ease was greater than 30 for each of the 76 questionnaires and greater than 60 for 66 (87%). Urinary tract infection, the costliest urological disease, has only 1 disease specific health related quality of life measure. Urolithiasis, the second costliest, has none.

Conclusions: The reading level of health related quality of life questionnaires in urology is appropriate for the reading ability of most adults in the United States. However, the most burdensome urological diseases lack disease specific health related quality of life instruments.