Time to start demanding a published retraction of their dubious conclusions?
Indeed. In this published paper (
the mediation analysis) in which the
fitness data was published, the authors
quietly acknowledged that their deconditioning hypothesis for CFS was not supported by their data. But it's only a very brief and subtle acknowledgement in one line of text; Blink and you'd miss it. The deconditioning theory was central to the PACE trial, because GET was designed to address and reverse deconditioning, as its fundamental mechanism of action. The step test was used to measure
fitness which was the trial's indicator of conditioning/deconditioning, so it's quite a big deal that
fitness did not improve after GET because it means that GET failed to improve deconditioning. Strange how there's so much fanfare in relation to the PACE trial's trumped-up, misleading and flawed claims of success, but then only a single line of fairly ambiguous text about the failure of the PACE trial to support the hypothesis upon which GET was based. And the fitness data, showing that GET failed to improve this objective measure of physical capacity, was buried in an obscure secondary analysis in the seventh-ish PACE trial paper, almost four years after the main paper was published. To acknowledge that their deconditioning theory (upon which GET was based) was not supported by the data in the biggest trial of GET for CFS, is a huge admission. They're basically admitting that they may have been wrong all these years about the nature of CFS (i.e. that CFS is not actually perpetuated by deconditioning after all, despite decades of aggressively claiming that this is the case, and saying that the patient community is misguided and foolish for thinking otherwise.) It's huge. But I doubt if we'll ever hear them admit it again. To admit that CBT and GET failed to clinically improve any of the objective measures in the PACE trial is an embarrassment for those who have built their careers aggressively claiming that CFS is reversible with CBT or GET. Which is why we'll never hear the authors making such an admission.
This is their subtle, brief and buried acknowledgement that their deconditioning theory has come crashing down around their heads in the biggest trial ever of GET for CFS. (Note that 'fitness' indicates 'conditioning', so a
lack of fitness equates to
deconditioning):
Chalder et al. 2015 said:
There were no effects on HADS anxiety, physical fitness, or the adjusted perception of effort measure (Borg scale).
Chalder et al. 2015 said:
We found that fitness and perception of exertion did not appear to mediate treatment effects, but that timed walking distance, assessed for the first time in our study, mediated the effect of GET. This suggests that increasing tolerance of physical activity might produce benefit without improving physical fitness.
Note that GET did
not result in a clinically useful effect in the timed walking distance test either, so their claim that "
timed walking distance .. mediated the effect of GET" seems a bit flaky, to say the least.