Cognitive behaviour therapy for adults with chronic fatigue syndrome

1. To systematically review all randomised controlled trials of cognitive-behaviour therapy (CBT) for adults with chronic fatigue syndrome (CFS); 2. To test the hypothesis that CBT is more effective than orthodox medical management or other interventions in adults with CFS.

1. Electronic searching of bibliographic databases, including Medline, PsycLIT, Biological Abstracts, Embase, SIGLE, Index to Theses, Index to Scientific and Technical Proceedings, and Science Citation Index, using multiple search terms in order to perform a highly sensitive search. 2. Electronic searching of the Trials Register of the Depression, Anxiety and Neurosis group. 3. Citation lists of relevant studies and reviews were perused for other relevant trials. 4. Contact with the principal authors of relevant studies, and with researchers in the field.

All randomised controlled trials were included in which - adult patients with CFS; - received CBT or a control intervention, being either orthodox medical management or another intervention; - and whose outcomes were assessed in an appropriate way. CBT could be either type 'A' (encouraging return to 'normal' levels of rest and activity) or type 'B' (encouraging rest and activity which were within levels imposed by the disorder).

The two reviewers worked independently throughout the selection of trials and data extraction, comparing findings only when there was disagreement. Relevant trials were allocated to one of three quality categories. Full data extraction, using a standardised data extraction sheet, was performed on studies which were of high or moderate quality. Trials of low quality were excluded from the review. The comparisons made to test the review hypothesis were of type 'A' CBT versus other intervention(s), and of type 'B' CBT versus other intervention(s). Functional outcome was used as the main outcome for comparison, but other appropriate outcomes were compared where possible. Results were synthesised using the Review Manager software. For dichotomous data, the odds ratio was calculated for each study. For continuous data, effect sizes were obtained and the standardised mean difference, with 95% confidence intervals, was calculated.

Only three relevant trials of adequate quality were found. These trials demonstrated that CBT significantly benefits physical functioning in adult out-patients with CFS when compared to orthodox medical management or relaxation. It is necessary to treat about two patients to prevent one additional unsatisfactory physical outcome about six months after treatment end. CBT appeared highly acceptable to the patients in these trials. There is no satisfactory evidence for the effectiveness of CBT in patients with the milder forms of CFS found in primary care or in patients who are so disabled that they are unable to attend out-patients. Additionally, there is no satisfactory evidence for the effectiveness of group CBT.

Cognitive behaviour therapy appears to be an effective and acceptable treatment for adult out-patients with chronic fatigue syndrome. CFS is a common and disabling disorder. Its sufferers deserve the medical profession to be more aware of the potential of this therapy to bring lasting functional benefit, and health service managers to increase its availability. Further research is needed in this important area. Trials should conform to accepted standards of reporting and methodology. The effectiveness of CBT in more and less severely disabled patients than those usually seen in out-patient clinics needs to be assessed. Trials of group CBT and in-patient CBT compared to orthodox medical management, and of CBT compared to graded activity alone, also need to be conducted.