Despite the wide availability of disease-related leaflets, their impact on patients' knowledge and well-being has rarely been evaluated. A randomized controlled study of a 'Rheumatoid Arthritis' leaflet revealed increased knowledge among the intervention group after 3 weeks. In addition, the leaflet was viewed as a source of reassurance. The purpose of the follow-up study was to determine whether the increase in knowledge was maintained in the longer term and to examine psychological well-being. Eighty-four patients (42 intervention and 42 control) completed the 6 month follow-up. There were no significant changes (P > 0.01) in mean outcome measures over the period 3 weeks-6 months for either the intervention or control groups. Patients in the intervention group retained the increase in knowledge observed at 3 weeks. Moreover, there was no evidence of adverse reactions to the leaflet in terms of psychological distress. Leaflets can be effective in promoting longer term increases in knowledge.