Response to Lancet article from Prof. Betsy Keller, Ph.D., Ithaca College






Prof. Betsy Keller’s response to Lancet Psychiatry report re M.E. and exercise compliments of Patricia Carter of MECFSForums.


What is at issue with both the primary and secondary analyses of the PACE Trial is:
1)  The fundamental misrepresentation of ME patients as being individuals defined by the archaic and non-specific Oxford criteria,


2) The tacit assumption that a statistically significant reduction in “fear avoidance beliefs” tracks with a meaningful decrease in functional impairment, the latter of which was not measured in the Pace trial.

Regarding diagnosis, use of the Oxford criteria for participant selection makes it likely that a portion of the study sample suffered from non-specific fatigue only.

Further, participation in the PACE Trial necessitated a moderate to high level of function, without representation from those who are severely ill. While this is not uncommon in most studies, it is a major limitation so that conclusions should be fairly characterized with this fact in mind. With respect to fear avoidance, I have yet to evaluate an adult-onset ME patient who did not want to recover their pre-illness level of function.

Many such patients still persist in overreaching on those ‘good days’ in hopes that they will miraculously not fall prey to a dreaded post-exertion symptom rebound that they have experienced many times before.

In contrast, the pediatric-onset ME patient typically learns early on that activity overreaching exacerbates symptoms, and absent the institutional memory of a prior ‘healthy’ life, they soon become ‘activity avoiders’. However, if you ask, these children will tell you that they also wish to be like other healthy kids.

For ME patients, activity overreaching equals symptom exacerbation, including decreased functional capacity. It’s a predictable action and reaction that is borne out by numerous and replicated physiological studies.

Given what we have learned in the past eight years about this illness, it is intellectually embarrassing to suggest that ME is a psychological illness. Likewise, to suggest that some with Me may not benefit from ‘support’ (CBT, support group or other) may rob patients of the opportunity to develop management (not healing) strategies that could be helpful.

However, with regard to GET, there are very, very few individuals in the world who truly understand the hairline trigger created by the aerobic metabolism pathology in these patients.

A statement proclaiming the efficacy of GET for those with ME must be founded on actual physiological evidence of positive physiological adaptation and no symptom exacerbation, and should not incude words such as “suggest” or “might” when encouraging therapists to promote more physical activities amongst their ME patients.

To state, as the authors have done, that the results of the PACE Trial provide sufficient evidence for therapists to couple CBT with GET is irresponsible and harmful. Notwithstanding the large sample size of the PACE Trial, outcome measures were simply not chosen to allow for such a conclusion regardless of the statistical power.

The Economist (1/17/15), not typically regarded as a foremost scientific or medical journal, reminded us in an article about the PACE analysis that the link between a healthy mind and healthy body has been well established for centuries.

So it is not surprising that helping one to understand their symptoms and learn supportive strategies to manage profound exhaustion, post-exertion symptom exacerbation, cognitive impairment, unrefreshing sleep, and often pain and dysregulated autonomic nervous system functions (orthostatic intolerance, POTS, GI symptoms and more), may be beneficial to a ME sufferer. 

However, as The Economist also pointed out, the healthy mind-body ink is “…by no means the same as saying something is all in the mind.”


Betsy Keller, Ph.D.
Ithaca, NY


Betsy Keller Professor, Department of Exercise and Sport Sciences
Faculty, School of Health Sciences and Human Performance
Ithaca College

Doctor of Philosophy in Exercise Science, University of Massachusetts
Master of Science in Exercise Science, University of Massachusetts
Bachelor of Science in Education, State University of New York, College at Cortland


“The Other Side Of The Stretcher” (c) 2015

This blog is not for medical advice.
For medical advice, you must speak with your physician!



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About The Other Side Of The Stretcher

Nurse turned patient, but not by choice. I was became a Registered Nurse in 1985 when I was 21 years old. That career was cut short the end of 1994 when I was unable to work anymore because of the illness M.E. or Myalgic Encephalomyelitis. I have 3 adult children including twins, A daughter and 2 sons. View all posts by The Other Side Of The Stretcher

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