Comment on: Cognitive behaviour therapy for the chronic fatigue syndrome: a randomized controlled trial. [BMJ. 1996]
EDITOR,-Michael Sharpe and colleagues conclude that cognitive behaviour therapy leads to a sustained reduction in functional impairment for patients with the chronic fatigue syndrome.1 The levels of disability of the 60 patients who took part in the study suggest, however, that these patients do not represent a comprehensive cross section of patients with the syndrome. The 60 patients scored 60-78 on the Karnofsky scale assessing disability and so represent a different population from the 143 patients reported on by Case History Research on ME (myalgic encephalomyelitis), who would have scored 30-60 (R Gibbons et al, first world congress on chronic fatigue syndrome and related disorders, Brussels, Nov 1995). Fifty nine of these 143 patients reported functional deterioration after sustained, incrementally increased physical exertion.
The authors did not assess other symptoms common in the chronic fatigue syndrome, such as pain, nausea, muscle weakness, or balance problems-a measure of the reduction of which was taken as a standard for “success” in an earlier trial.2 The lack of evidence of significant changes in other measures besides “the principal complaint of severe fatigue” in the authors’ study tends to diminish the validity of their conclusions.
You can read the full comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2350876/pdf/bmj00539-0052c.pdf
Source: Gibbons R, Macintyre A, Richards C. Cognitive behaviour therapy for the chronic fatigue syndrome. Patients were not representative of all patients with the syndrome. BMJ. 1996 Apr 27;312(7038):1096; author reply 1098. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2350876/