To develop and assess the effectiveness of a drug information leaflet (DIL) for D-penicillamine (DPA) and determine whether additional verbal information provides enhanced benefit.
Three preliminary studies were undertaken: a reading age study; the development of a DIL for DPA; and a DPA knowledge questionnaire. The primary study assessed the effect of the DIL on the knowledge of 30 patients at weeks 0 and 24 after commencing DPA. A follow-up study of 100 patients randomly assigned to receive the DIL alone (control group) or with additional verbal backup (experimental group) determined the effects of additional verbal information by comparison of DPA knowledge questionnaire scores at weeks 0 and 24.
The reading study showed that 12% of the sample had difficulty reading and so the DPA DIL was designed to be easy to read using the Flesch Reading Index. An assessment of knowledge of DPA prior to reading the DIL resulted in scores ranging from 0 to 13 with a median of 2 (maximum possible 14). By week 24 the median score was 10 (range 6-14), which was significant at P < 0.0001. The assessment of additional verbal backup showed that both the control group and the experimental group knew little about DPA on study entry, with a median score 2 in each group. On study exit, both groups knew significantly more (P < 0.001) about the drug; the control group scored 9 and the experimental group 11 (not significantly different; P=0.109).
A large minority of patients have poor reading skills, but when a DIL is designed to be easy to read patients gain significant amounts of knowledge from it. Providing additional verbal explanations did bring about increases in knowledge but these were not significant.