PACE Review

The main findings reported in the PACE trial were that cognitive behavioral therapy (CBT) and graded exercise therapy (GET) were moderately effective treatments for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), and fear avoidance beliefs constituted the strongest mediator of both therapies. These findings have been challenged by patients and, more recently, a number of top scientists, after public health expert Tuller, highlighted methodological problems in the trial. As a doctor who has been bedridden with severe ME for a long period, I analyzed the PACE trial and its follow-up articles from the perspectives of a doctor and a patient. During the PACE trial the eligibility criteria, both subjective primary outcomes, and most of the recovery criteria were altered, creating an overlap of the eligibility and recovery criteria; consequently, 13% of patients were considered “recovered,” with respect to 1 or 2 primary outcomes, as soon as they entered the trial. In addition, 46% of patients reported an increase in ME/CFS symptoms, 31% reported musculoskeletal and 19% reported neurological adverse events. Therefore the proportion negatively affected by CBT and GET would be between 46% and 96%, most likely estimated at 74%, as shown in a large survey recently conducted by the ME Association. Medication with such high rates of adverse events would be withdrawn with immediate effect. There was no difference in long-term outcomes between adaptive pacing therapy, CBT, GET and specialist medical care, and none of them were effective, invalidating the biopsychosocial model and use of CBT and GET for ME/CFS. The discovery that an increase in exercise tolerance did not lead to an increase in fitness means that an underlying physical problem prevented this; validates that ME/CFS is a physical disease and that none of the treatments studied addressed this issue

10 Replies

  • Yes I read this article today.  Yet another drubbing for the PACE trial.  We live in hope that all these articles and studies picking the so called science to pieces will finally sound the death knell for PACE.

  • Evidence which has been covered up for years is coming out again and the truth will out for everyone to see. How much longer can the universities / The Lancet claim this flawed study should not be retracted.

  • The Lancet which published PACE in 2011 is also feeling the pressure.


  • It is known that the instances of bad science, usually for monetary or kudos gain, are alarmingly on the increase.  This article (in 2012) claims that the instances of scientific papers being retracted for fraud, yes fraud, has had a ten fold increase since 1975.

    This article (Dec 2015) even contains a quote on the matter from guess who.  Richard Horton the Editor in Chief of the Lancet that published the flawed PACE trial.  He claims "Afflicted by studies with small sample sizes, tiny effects, invalid exploratory analyses and flagrant conflicts of interest, together with an obsession for pursuing fashionable trends of dubious importance, science has taken a turn towards darkness."

    The hypocrisy beggars belief!

  • Hypocrisy from the Lancets editor has he no shame.

  •  A competitive system of doing science supposedly self correcting but the truth is one of the first casualties. 

    Universities reputations, journals impact factor and prestigious careers all count for more than the living deaths of patients looking for relief from suffering. 

    Medical politics has patient interests/ rights a long way from top priority which is why every trick in the book will be used in trying to prevent retraction.

  • Interesting article.  I don't pretend for one minute to have read it all properly or to understand it in any sort of detail.  I have really only skimmed most of it and like most scientific papers it's the introduction and the last few sections that I concentrate on.

    However, it seems to me PACE would have failed on all six of the corollaries mentioned.

    There are some very apt and interesting comments in there like

    "Second, most research questions are addressed by many teams, and it is misleading to emphasize the statistically significant findings of any single team. What matters is the totality of the evidence. Diminishing bias through enhanced research standards and curtailing of prejudices may also help."


    "As described above, whenever ethically acceptable, large studies with minimal bias should be performed on research findings that are considered relatively established, to see how often they are indeed confirmed. I suspect several established “classics” will fail the test".

    Sadly your overall comment about medical politics and it's priorities is alarmingly all too true.

  • Later this month a freedom of information request for data from PACE will be heard at first stage tribunal. Hearing the universities appeal against the data commissioners ruling the data should be released for independent evaluation, also adds pressure within the scientific community for action which corrects the errors by retracting the papers from journals.

  • When government health policies use research findings reproducibility and reliable research are of more than academic interest. 

  • Medication with such adverse effects would have been withdrawn an exact opposite of recommended that NHS provides on their web site.