Developing a register of randomised controlled trials in primary care.

OBJECTIVE: To determine the number, nature, site of publication, and feasibility of identifying randomised controlled trials relevant to primary care. DESIGN: Review of literature using three strategies: approaching journal editors, Medline search, and manual search of individual journals. SETTING: Journals containing publications of studies based in primary care. MAIN OUTCOME MEASURES: The number, site of publication, and subject of trials identified. RESULTS: No journal had a system which enabled identification of all the randomised controlled trials it published. 266 trials relevant to primary care were identified from 110 different journals during 1987-91 by Medline. Of these, only 62 trials were published in primary care journals. Hand searching of seven major primary care research journals showed that between 13% and 38% of the trials had been missed by the Medline search. Of the trials identified, 47 (18%) were concerned with mental disease (including neuroses, tobacco misuse and alcohol misuse) and 43 (16%) were concerned with hypertension. CONCLUSION: Given the diversity of publication sources and topics, this supports the need for a centrally based register of randomised controlled trials that may be relevant to primary care overviews in the future.