by Sasha Nimmo

Large controversial UK study refusing to release data: PACE trial

The authors of a £5 million trial into cognitive behavior therapy and graded exercise therapy again refused to release the data to scientists who wanted to examine it. The Queen Mary University of London believe it to be exempt from Freedom of Information (FOI) laws; here is the full letter of refusal.

To refresh your memory, the authors of the PACE trial said:

“We did a randomised controlled trial (n=640) and found two rehabilitative treatments, graded exercise therapy (GET) and cognitive behaviour therapy (CBT), added to specialist medical care to be superior to adaptive pacing therapy added to specialist medical care and specialist medical care alone in improving fatigue and physical functioning for patients with chronic fatigue syndrome.”

The PACE trial was published in The Lancet in 2011 and since then many patient groups and scientists have criticised the study, most notably the UK’s ME AssociationJames Coyne and David Tuller, who is a lecturer at Berkeley school of journalism (University of California) and has a master’s degree in public health. Tuller pointed out flaws in the trial and quoted expert doctors:

“Dr. Bruce Levin, Columbia University: “To let participants know that interventions have been selected by a government committee ‘based on the best available evidence’ strikes me as the height of clinical trial amateurism.”

Dr. Ronald Davis, Stanford University: “I’m shocked that the Lancet published it…The PACE study has so many flaws and there are so many questions you’d want to ask about it that I don’t understand how it got through any kind of peer review.”

Dr. Arthur Reingold, University of California, Berkeley: “Under the circumstances, an independent review of the trial conducted by experts not involved in the design or conduct of the study would seem to be very much in order.”

Dr. Jonathan Edwards, University College London: “It’s a mass of un-interpretability to me…All the issues with the trial are extremely worrying, making interpretation of the clinical significance of the findings more or less impossible.”

Dr. Leonard Jason, DePaul University: “The PACE authors should have reduced the kind of blatant methodological lapses that can impugn the credibility of the research, such as having overlapping recovery and entry/disability criteria.””

The main criticisms of the trial were summarised by Tuller:

  • the study included a bizarre paradox: participants’ baseline scores for the two primary outcomes of physical function and fatigue could qualify them simultaneously as disabled enough to get into the trial but already “recovered” on those indicators–even before any treatment. In fact, 13 percent of the study sample was already “recovered” on one of these two measures at the start of the study.
  • there was very little difference in outcomes at long-term follow-up between any of the four interventions.
  • The PACE claims of successful treatment and “recovery” were based solely on subjective outcomes. All the objective measures from the trial—a walking test, a step test, and data on employment and the receipt of financial information—failed to provide any evidence to support such claims. Afterwards, the PACE authors dismissed their own main objective measures as non-objective, irrelevant, or unreliable.
  • In the middle of the study, the PACE team published a newsletter for participants that included glowing testimonials from earlier trial subjects about how much the “therapy” and “treatment” helped them.
  • More here.

The PACE trial authors are also in breach of orders to share the data. The UK’s Information Commissioner’s Office ordered Queen Mary University of London to release the data. The UK Medical Research Council 2011 policy on data sharing has endorsed principles laid out by the Research Councils UK including:

Publicly funded research data are a public good, produced in the public interest, which should be made openly available with as few restrictions as possible in a timely and responsible manner. To enable research data to be discoverable and effectively re-used by others, sufficient metadata should be recorded and made openly available to enable other researchers to understand the research and re-use potential of the data. Published results should always include information on how to access the supporting data.

More than 11,700 people and organisations have signed a petition to call upon The Lancet to retract claims of recovery, to give independent researchers access to the data and call upon all parties to reject the view that being as disabled as patients with congestive heart failure is a good recovery of physical function in CFS.

More reading: 

As well as the links above, three letters recently published in The Lancet are worth reading:

Results of the PACE follow-up study are uninterpretable”, from James Coyne and Keith Laws

PACE: CBT and GET are not rehabilitative therapies”, from Frank Twisk

The ME Association’s letter