New research, presented at the 2008 Clinical Congress of the American College of Surgeons, suggests that patients often misinterpret or completely misunderstand the medical questionnaires given to them at doctors' offices. This lack of understanding stems from both literacy and numeracy problems in much of the population, and may lead to doctors being provided with inaccurate information regarding the patient's medical history.

If patient is unable to communicate his or her medical history to the doctor, this may seriously hinder the doctor's ability to diagnose and treat the patient effectively.

Researchers questioned 300 men at an inner-city hospital, whose average reading level was at the fourth grade level. Subjects were asked seven questions from the International Prostate Symptom Score (IPSS) test. Only 16% understood all the questions, 38% understood at least half the questions, 18% understood less than half, and 28% misunderstood all questions.

A second group of men was asked three questions that assessed their numeracy, that is, their aptitude with numbers. About a third of the participants answered only one question correctly and another third had no correct answers. The test consisted of questions such as, "if a coin is flipped 1,000 times, about how many times do you think it will come up heads?"

The researchers found that adding illustrations to the tests did not improve results — however, using a specially designed computer program in which a character asked the patients questions did significantly improve understanding of the IPSS test.

One of the study's authors, Viraj A. Master, says that "[b]eing innumerate, in addition to being illiterate, results in high levels of misunderstanding that severely limit access to appropriate health care." If patient is unable to communicate his or her medical history to the doctor, this may seriously hinder the doctor's ability to diagnose and treat the patient effectively.

Master also warns doctors that "[t]here is a true epidemic of health illiteracy in this country. Do not assume that your patients are literate with either prose or numeracy."

The research was conducted by investigators at the Emory University School of Medicine in Atlanta, GA.