Tag: 2017

The problem of bias in behavioural intervention studies: Lessons from the PACE trial

Abstract:

Geraghty’s recent editorial on the PACE trial for chronic fatigue syndrome has stimulated a lively discussion. Here, I consider whether the published claims are justified by the data. I also discuss wider issues concerning trial procedures, researcher allegiance and participant reporting bias. Cognitive behavioural therapy and graded exercise therapy had modest, time-limited effects on self-report measures, but little effect on more objective measures such as fitness and employment status. Given that the trial was non-blinded, and the favoured treatments were promoted to participants as ‘highly effective’, these effects may reflect participant response bias. In non-blinded trials, the issue of reporting biases deserves greater attention in future.

Source: Wilshire C. The problem of bias in behavioural intervention studies: Lessons from the PACE trial. J Health Psychol. 2017 Aug;22(9):1128-1133. doi: 10.1177/1359105317700885. Epub 2017 Mar 23. https://www.ncbi.nlm.nih.gov/pubmed/28805526

PACE-GATE: An alternative view on a study with a poor trial protocol

Abstract:

The controversies surrounding the effectiveness of cognitive behavioural therapy and graded exercise therapy for chronic fatigue syndrome are explained using Cohen’s d effect sizes rather than arbitrary thresholds for ‘success’. This article shows that the treatment effects vanish when switching to objective outcomes. The preference for subjective outcomes by the PACE trial team leads to false hope. This article provides a more realistic view, which will help patients and their doctors to evaluate the pros and cons.

Source: Stouten B. PACE-GATE: An alternative view on a study with a poor trial protocol. J Health Psychol. 2017 Aug;22(9):1192-1197. doi: 10.1177/1359105317707531. Epub 2017 May 12. https://www.ncbi.nlm.nih.gov/pubmed/28805525

PACE trial authors continue to ignore their own null effect

Abstract:

Protocols and outcomes for the PACE trial were changed after the start of the trial. These changes made substantial differences, leading to exaggerated claims for the efficacy of cognitive behavior therapy and graded exercise therapy in myalgic encephalomyelitis/chronic fatigue syndrome. The small, self-reported improvements in subjective measures cannot be used to say the interventions are effective, particularly in light of the absence of objective improvement. Geraghty’s criticism of the trial was reasonable and supported by the evidence.

Source: Vink M. PACE trial authors continue to ignore their own null effect. J Health Psychol. 2017 Aug;22(9):1134-1140. doi: 10.1177/1359105317703785. Epub 2017 Apr 27. https://www.ncbi.nlm.nih.gov/pubmed/28805519

The PACE trial missteps on pacing and patient selection

Abstract:

As others have pointed out a variety of complicating factors with the PACE trial (e.g. changing outcome criteria), I will limit my remarks to issues that involve the composition of adaptive pacing therapy and issues involving patient selection. My key points are that the PACE trial investigators were not successful in designing and implementing a valid pacing intervention and patient selection ambiguity further compromised the study’s outcomes.

Source: Jason LA. The PACE trial missteps on pacing and patient selection. J Health Psychol. 2017 Aug;22(9):1141-1145. doi: 10.1177/1359105317695801. Epub 2017 Feb 1. https://www.ncbi.nlm.nih.gov/pubmed/28805518

Response to the editorial by Dr Geraghty

Abstract:

This article is written in response to the linked editorial by Dr Geraghty about the adaptive Pacing, graded Activity and Cognitive behaviour therapy; a randomised Evaluation (PACE) trial, which we led, implemented and published. The PACE trial compared four treatments for people diagnosed with chronic fatigue syndrome. All participants in the trial received specialist medical care. The trial found that adding cognitive behaviour therapy or graded exercise therapy to specialist medical care was as safe as, and more effective than, adding adaptive pacing therapy or specialist medical care alone. Dr Geraghty has challenged these findings. In this article, we suggest that Dr Geraghty’s views are based on misunderstandings and misrepresentations of the PACE trial; these are corrected.

Source: White PD, Chalder T, Sharpe M, Angus BJ, Baber HL, Bavinton J, Burgess M, Clark LV, Cox DL, DeCesare JC, Goldsmith KA, Johnson AL, McCrone P, Murphy G, Murphy M, O’Dowd H, Potts L, Walwyn R, Wilks D. Response to the editorial by Dr Geraghty. J Health Psychol. 2017 Aug;22(9):1113-1117. doi: 10.1177/1359105316688953. Epub 2017 Jan 24. https://www.ncbi.nlm.nih.gov/pubmed/28805524

The PACE trial: It’s time to broaden perceptions and move on

Abstract:

The continued critiques of the PACE trial highlight how differing beliefs about the causes of chronic fatigue syndrome still influence how scientific studies in this area are accepted and evaluated. Causal beliefs about chronic fatigue syndrome and a modern version of Cartesian dualism are important in understanding the reaction to the PACE trial. The continued debate on the PACE trial seems to miss the fact that science is incremental. An unfortunate outcome of the PACE controversy and intimidation of researchers may be less research in the area. It is time to move on from criticism and collect more data on effective treatments.

Source: Petrie KJ, Weinman J. The PACE trial: It’s time to broaden perceptions and move on.J Health Psychol. 2017 Aug;22(9):1198-1200. doi: 10.1177/1359105317703789. Epub 2017 Apr 10. https://www.ncbi.nlm.nih.gov/pubmed/28805523

PACE trial claims for recovery in myalgic encephalomyelitis/chronic fatigue syndrome – true or false? It’s time for an independent review of the methodology and results

Abstract:

The PACE trial set out to discover whether cognitive behaviour therapy and graded exercise therapy are safe and effective forms of treatment for myalgic encephalomyelitis/chronic fatigue syndrome. It concluded that these interventions could even result in recovery. However, patient evidence has repeatedly found that cognitive behaviour therapy is ineffective and graded exercise therapy can make the condition worse. The PACE trial methodology has been heavily criticised by clinicians, academics and patients. A re-analysis of the data has cast serious doubts on the recovery rates being claimed. The trust of patients has been lost. The medical profession must start listening to people with myalgic encephalomyelitis/chronic fatigue syndrome if trust is going to be restored.

Source: Shepherd CB. PACE trial claims for recovery in myalgic encephalomyelitis/chronic fatigue syndrome – true or false? It’s time for an independent review of the methodology and results. J Health Psychol. 2017 Aug;22(9):1187-1191. doi: 10.1177/1359105317703786. Epub 2017 Apr 9. https://www.ncbi.nlm.nih.gov/pubmed/28805522

Once again, the PACE authors respond to concerns with empty answers

Abstract:

In their response to Geraghty, the PACE investigators state that they have “repeatedly addressed” the various methodological concerns raised about the trial. While this is true, these responses have repeatedly failed to provide satisfactory explanations for the trial’s very serious flaws. This commentary examines how the current response once again demonstrates the ways in which the investigators avoid acknowledging the obvious problems with PACE and offer non-answers instead-arguments that fall apart quickly under scrutiny.

Source: Tuller D. Once again, the PACE authors respond to concerns with empty answers. J Health Psychol. 2017 Aug;22(9):1118-1122. doi: 10.1177/1359105317703788. Epub 2017 Apr 27. https://www.ncbi.nlm.nih.gov/pubmed/28805521

Further commentary on the PACE trial: Biased methods and unreliable outcomes

Abstract:

Geraghty in the year 2016, outlines a range of controversies surrounding publication of results from the PACE trial and discusses a freedom of information case brought by a patient refused access to data from the trial. The PACE authors offer a response, writing ‘Dr Geraghty’s views are based on misunderstandings and misrepresentations of the PACE trial’. This article draws on expert commentaries to further detail the critical methodological failures and biases identified in the PACE trial, which undermine the reliability and credibility of the major findings to emerge from this trial.

Source: Geraghty KJ. Further commentary on the PACE trial: Biased methods and unreliable outcomes. J Health Psychol. 2017 Aug;22(9):1209-1216. doi: 10.1177/1359105317714486. Epub 2017 Jun 14. https://www.ncbi.nlm.nih.gov/pubmed/28805517

Do graded activity therapies cause harm in chronic fatigue syndrome?

Abstract:

Reporting of harms was much better in the PACE (Pacing, graded Activity, and Cognitive behavioural therapy: a randomised Evaluation) trial than earlier chronic fatigue syndrome trials of graded exercise therapy and cognitive behavioural therapy. However, some issues remain. The trial’s poor results on objective measures of fitness suggest a lack of adherence to the activity component of these therapies. Therefore, the safety findings may not apply in other clinical contexts. Outside of clinical trials, many patients report deterioration with cognitive behavioural therapy and particularly graded exercise therapy. Also, exercise physiology studies reveal abnormalities in chronic fatigue syndrome patients’ responses to exertion. Given these considerations, one cannot conclude that these interventions are safe and risk-free.

Source: Kindlon T. Do graded activity therapies cause harm in chronic fatigue syndrome? J Health Psychol. 2017 Aug;22(9):1146-1154. doi: 10.1177/1359105317697323. Epub 2017 Mar 20. https://www.ncbi.nlm.nih.gov/pubmed/28805516