A system has been developed to collect and process clinical trial data in general practice using a hand-held computer in the patient's presence. It was based on a Psion Organiser II (model XP) computer using software produced for the trial. The major advantages are: (a) avoidance of protocol violations and other incorrect data entries; and (b) saving of time for investigators and company personnel. The present coding of symptoms was found to be the only major drawback, but this problem could be remedied for future studies.
