Re: Updated NICE guidance on chronic fatigue syndrome
The recent editorial by Turner-Stokes and Wade on NICE guidance on myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) includes several problematic statements.
The editorial writes, for example, that “trials in people with CFS/ME typically allocate participants to one or more isolated interventions—such as cognitive behavioural therapy, graded exercise therapy, or adaptive pacing— regardless of their actual needs or preferences.” It should be noted that some randomized trials tested a combination of these approaches and nonetheless reported disappointing results. [1, 2] By using a metaphor that some patients were provided with trousers only, and others with just a jacket instead of a well-tailored suit, the editorial makes a caricature of how these trials were conducted. In the largest study, for example, exercise therapy was already well-tailored to the individual with participant feedback and mutual planning of personal goals between patient and therapist. Despite this, the exercise group failed to outperform a passive control group at long-term follow-up. 
Turner-Stokes and Wade also argue that the quality criteria used by the GRADE system are poorly applicable to trials on complex interventions such as rehabilitation for people with ME/CFS. As an example, they mention that double-blinding is impossible in trials on interventions that require patients’ active participation. In such instances, however, quality criteria usually recommend using objective outcomes (in addition to subjective ones) as these are less prone to various biases.  Randomized trials on rehabilitative interventions for ME/CFS have included several objective outcomes such as work resumption, healthcare utilization, actigraphy, and various fitness tests. The results of these objective outcomes were summarized in a review by Vink & Vink-Niese.  Overall these showed no clinically significant improvements which was likely one of the reasons for the NICE guideline committee to downgrade the evidence for rehabilitative interventions to low or very low quality. If large effects were seen on objective outcomes including ME/CFS patients returning to work, increasing their fitness level, or requiring less healthcare, the committee would likely not have downgraded the results of these trials.
The editorial pleads for “systematic collection and longitudinal analysis of real life clinical data on a large scale.” Data from routine clinical practice already exists and generally supports the above-mentioned conclusion. In Belgium, for example, exercise therapy and cognitive behavioral therapy were used as the standard treatments for ME/CFS since the creation of government-funded centers in 2002. The data collected by these centers indicate that patients did not increase their fitness level or return to work.  Turner-Stokes and Wade also write that “many patients do recover from chronic fatigue symptoms”. If this statement refers to ME/CFS, the subject of the draft guideline, then it is at odds with a systematic review on the prognosis of ME/CFS which indicates low recovery rates with a median of only 5 percent. 
Lastly, Turner-Stokes and Wade suggest that the general concept of exercise is seen as harmful in the ME/CFS patient community because “many find themselves fobbed off with a prescription for gym membership or a course of exercise classes under the pretext of evidence based practice.” Surveys by ME/CFS patient organizations however indicate that reports of harm following exercise therapy are also high if treatment was guided by an NHS specialist. As noted by Kirke, “poor implementation does amplify this harm, but well-implemented GET still causes worsening for most patients.” 
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2. Wearden AJ, Dowrick C, Chew-Graham C, Bentall RP, Morriss RK, Peters S, et al. Nurse led, home based self help treatment for patients in primary care with chronic fatigue syndrome: randomised controlled trial. BMJ. 2010;340:c1777.
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8. Kirke KD. PACE investigators’ response is misleading regarding patient survey results. J Health Psychol. 2017;22:1168–76.
Competing interests: No competing interests