Consent forms: how to determine and improve their readability

This study investigated the reading level estimates of cancer clinical trial consent forms from actively accruing studies at the Medicine Branch and the Clinical Pharmacology Branch of the National Cancer Institute. Forty-four consent forms were analyzed using the SMOG formula. Readability levels ranged from grade 12 to grade 17.5 (mean = 14.3). The conclusion was that these consent forms were written above most subjects' reading levels. The usefulness of consent forms could be improved significantly by using readability formulas, applying rewriting techniques, and being aware of subjects' comprehension levels. This paper suggests a number of strategies that nurses can use to enhance comprehension of the information contained in informed consent documents.