Antibiotics for sore throat to prevent rheumatic fever: yes or no? How the Cochrane Library can help.

around the corner you anticipate numerous patient enquiries and visits related to the use of antibiotics for the common cold and associated morbidities. One day a 45-year-old woman, a recent immigrant from India, presents to your office with sore throat and fever of 2 days’ duration. In India her male cousin acquired rheumatic fever following a sore throat for which he did not receive antibiotics. She is now worried about getting rheumatic fever herself and insists on having antibiotics prescribed. You decide to search the Cochrane Library (www .cochrane.org/reviews/clibintro .htm), to which your practice group subscribes, for evidence of the effectiveness of antibiotics for sore throat to prevent rheumatic fever. You log on and open Issue 3, 2004, and in the search box you enter the terms “(sore throat) and (antibiotics) and (rheumatic fever) and (primary care)” (Fig. 1). You find the review “Antibiotics for sore throat.” By printing the review, you obtain 41 pages of text with an abstract including “reviewers’ conclusions.” (A lay summary of the review is available at Informed Health Online (www.informed healthonline.org//item.aspx?tabid =8&review=000023), and that Web site has a direct link to the abstract of the review in the Cochrane Library.) After opening the review, you click on “outline” at the top of the tool bar, and the outline appears on the left of your screen. At the bottom left you click on “metaview graphs” and the outcome “Incidence of acute rheumatic fever within 2 months” is displayed as a forest plot. You notice that the authors have used an odds ratio (0.30, 95% confidence interval [CI] 0.20 to 0.45) as the default statistic for this outcome (Fig. 2). In the forest plot, no weights are assigned to the studies in which no outcomes in both the treatment and control groups occurred. Not being a gambler, you have a poor understanding of odds ratios. You are more familiar with the Antibiotics for sore throat to prevent rheumatic fever: Yes or No? How the Cochrane Library can help THE COCHRANE LIBRARY PR AC T I C E