Medically unexplained symptom management Andreas Schröder, Michael Sharpe, Per Fink  The Lancet Psychiatry  Volume 2, Issue 7, Pages 587-588 (July 2015) DOI: 10.1016/S2215-0366(15)00233-3 Copyright © 2015 Elsevier Ltd Terms and Conditions

Figure Effect of cognitive-behavioural group treatment in various subgroups Between-group effect sizes are presented (Cohen's d) with 95% CIs for various subgroups from our trial5 16 months after randomisation. We used the Cochrane review's4 primary outcome—somatic symptoms (measured with the Symptom Checklist-90-Revised somatisation subscale)—to calculate effect sizes as between-group differences in mean change since baseline divided by pooled SD (n=120) at baseline. The statistical analysis was done as it was in the original trial. Effect sizes are presented for various subgroups according to either diagnostic group or illness severity, and for the whole trial sample for comparison. Because many patients meet diagnostic criteria for several functional somatic syndromes, diagnostic groups are not independent. Diagnoses are based on functional somatic symptoms in the past 2 years according to diagnostic interview and review of clinical records.2,5 We used existing diagnoses (notwithstanding their low validity) rather than previously reported symptom clusters2,5 for this analysis because they are widely used in both research and clinical care. We defined the most severely ill patients as those who reported more than 30 functional somatic symptoms during the past 2 years and who had severe impairment in daily living according to the clinician. Because these patients meet diagnostic criteria for more functional somatic syndromes than do patients with less severe illness, they are over-represented in each diagnostic group, explaining why effect sizes of diagnostic groups are slightly smaller than the overall trial effect is. The solid line shows no effect and the dashed line shows the effect size for all patients. CBT=cognitive behavioural therapy. The Lancet Psychiatry 2015 2, 587-588DOI: (10.1016/S2215-0366(15)00233-3) Copyright © 2015 Elsevier Ltd Terms and Conditions