Key points are not available for this paper at this time.
of effective guidelines. One prerequisite is an ongoing review of evidence on the outcome of different approaches to management. This has been done for perinatal care and so far over 5000 perinatal trials have been identified and classified." Guidelines should be based on the best available evidence, and assembling this is hard work. Help is at hand. The proposed Cochrane Centre will have an important role in fostering systematic, up to date reviews of controlled trials (see next editorial)."2 Leeds has a clearing house for assessing health services' outcomes, which circulates a quarterly bulletin.'3 In future, a guideline coordinating centre could collaborate closely with the royal colleges, which have already worked in this area,14-'6 and other local, national, and international bodies.
Chalmers et al. (Sat,) studied this question.