Background
The effectiveness of the informed consent process is poorly understood and not well researched. Many fac-tors are involved: economic, legal, institutional, edu-cational, cultural, religious, and interpersonal. Poor patient understanding can be due to poor communi-cation techniques or to a lack of time on the part of health care professionals, to patient anxiety or denial or, as much of the existing literature reveals, to a lack of reading comprehension. Patients do not always re-alize the purpose of the information and the consent form.8–10 Cassileth et al.8 evaluated the recall of cancer patients who were given consent forms and verbal ex-planations. They found that the day after patients signed consent forms, only 60 percent understood the purpose of the forms and only 55 percent were able to identify a major risk. Expressing and understand-ing risk is a problem faced by physician and patient alike. Merz et al.,11 in a study of informed consent litigation, noted that there was no consistency in the verbal expressions used by physicians to categorize risk. In general, physicians have difficulty in express-ing subjective probabilities as odds ratios or decimal figures.
Studies of the comprehension of health education handouts show that, typically, only half the recipients are able to comprehend health education materials.12,13 Studies of readability suggest that the existing forms for informed consent are often too complex and dif-ficult for the average person to understand.14–22 Mor-rowetal.17 noted that consent forms are less compre-hensible than the popular press and that research consent forms may be as difficult to read as medical journals. When the Fry readability scale23 was used to