QUALITY OF NONSTRUCTURED AND STRUCTURED ABSTRACTS OF ORIGINAL RESEARCH ARTICLES IN THE BRITISH-MEDICAL-JOURNAL, THE CANADIAN-MEDICAL-ASSOCIATION-JOURNAL AND THE JOURNAL-OF-THE-AMERICAN-MEDICAL-ASSOCIATION

Objective: To assess and compare the quality of nonstructured and stru ctured abstracts of original research articles in three medical journa ls. Design: Blind, criterion-based observational study. Sample: Random sample of 300 abstracts (25 abstracts per journal each year) of artic les published in the British Medical Journal (BMJ), the Canadian Medic al Association Journal and the Journal of the American Medical Associa tion (JAMA) in 1988 and 1989 (nonstructured abstracts) and in 1991 and 1992 (structured abstracts). Main outcome measures: The quality of ab stracts was measured against 33 objective criteria, which were divided into eight categories (purpose, research design, setting, subjects, i ntervention, measurement of variables, results and conclusions). The q uality score was determined by dividing the number of criteria present by the number applicable; the score varied from 0 to 1. Results: The overall mean quality scores for nonstructured and structured abstracts were 0.57 and 0.74 respectively (p < 0.001). The frequency in meeting the specific criteria was generally higher for the structured abstrac ts than for the nonstructured ones. The mean quality score was higher for nonstructured abstracts in JAMA than for those in BMJ (0.60 v. 0.5 4, p < 0.05). The scores for structured abstracts did not differ signi ficantly between the three journals.