On 2018 Jan 09, Tom Kindlon commented:
Response to: Guided graded exercise self-help plus specialist medical care versus specialist medical care alone for chronic fatigue syndrome (GETSET): a pragmatic randomised controlled trial
The SF-36 physical functioning (PF) outcomes for those in the guided graded exercise selfhelp (GES) group who had a baseline SF-36 PF score ≥45 (call them group B) must have been particularly poor in the GETSET trial.1 We are told that those with a baseline score ≤40 (group A) made up approximately 40% of the sample and ended with average score of 56.9. This means the average outcome for group B, the higher functioning group at baseline, was actually lower, at around 54.9. Also, by definition, group A increased by an average of at least 16.9 (56.9-40). However the whole sample only increased by an average of 8.4. This means that an upper bound on the average increase for group B would be only approximately 2.7, in comparison to the increase of 16.9 for group A. This is an extreme scenario and the difference in improvements was most likely higher than 14.2. It would be interesting if Clark and colleagues could give the exact figure so everyone would be aware of the magnitude of the difference in the response.
Clark and colleagues say the poor results may be due to a ceiling effect. More than 90% of healthy working-age people score 90 or more.2 Therefore, the mean score of 54.9 for group B and 55.7 overall suggests that if there is a ceiling in the effectiveness of GES, it is a long way below normal functioning. I do not believe this was made clear to readers.
Tom Kindlon
Competing interests: I work in a voluntary capacity for the Irish ME/CFS Association.
References:
1 Clark LV, Pesola F, Thomas J, Vergara-Williamson M; Beynon M, White PD. Guided graded exercise self-help plus specialist medical care versus specialist medical care alone for chronic fatigue syndrome (GETSET): a pragmatic randomised controlled trial. The Lancet. June 22, 2017 doi:10.1016/S0140-6736(16)32589-2
2 Wilshire CE, Kindlon T, Matthees A, McGrath S. Can patients with chronic fatigue syndrome really recover after graded exercise or cognitive behavioural therapy? A critical commentary and preliminary re-analysis of the PACE trial. Fatigue. 2017;5:1–4.
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