The opening paragraph of the paper by Thompsonet al (see page 78) goes to the heart of a major problem in clinical research which is that most thinking, research, teaching, and clinical guidance on medical conditions, in this case irritable bowel syndrome (IBS), are based on patients referred by general practitioners to specialists. For a number of reasons our knowledge of the natural history and optimum management of many conditions frequently encountered in general practice and primary care remain relatively scanty. Indeed, the stimulus to undertake this study came from a previous survey1 in which the same authors found that general practitioners, despite their unfamiliarity with diagnostic criteria for IBS, diagnosed the condition with reasonable confidence, found it less troublesome than many other painful conditions such as pelvic pain, headache and backache and only referred a minority of patients to specialists. In that questionnaire survey general practitioners estimated that they referred about one in seven patients with IBS to specialists and in the …