However, looking at the original data of the follow-up study and other PACE trials (McCrone
et al. , 2012; Twisk et al., 2009), we believe that neither CBT nor GET qualify as rehabilitative therapies for all CFS or ME patients.
First, the PACE trial investigated the effects of CBT and GET in chronic fatigue, as defined by the 1991 Oxford criteria – not in CFS/ME as defined by the other case criteria, let alone ME cases.
The study used such a broad definition of the disease that it is likely to have included many patients who did not truly have CFS at all (Smith et al., 2015). Second, the positive effect of CBT and GET on subjective measures, fatigue and physical functioning cannot be qualified as sufficient. Third, the PACE trial follow-up study (Sharpe et al., 2015) concluded that outcomes with SMC alone or APT were similar to those achieved with CBT and GET at follow-up. This finding suggests that the vast majority of patients improved subjectively to the same level with
SMC and APT as with CBT and GET, without the need for additional therapies (including CBT and GET).
In brief, CBT and GET are moderately effective in subjective terms in chronic fatigue. However
looking at the patients studied and the (subjective and objective) outcomes of the PACE trial, CBT and GET do not meet the requirements for rehabilitative or effective therapies for CFS, let alone for ME sufferers. The PACE trial design changed so significantly that many experts were left wondering whether there is any value in the study itself.
Firstly, the physical functioning threshold in SF-36 was lowered because of poor recruitment; this increased the likelihood that many participants did not have ME/CFS at all. Secondly, rhe authors claimed to have performed an intention-to-treat analysis, but in fact they excluded any subjects fpr whom there were no primary outcome data, and so it was not an intention-to-treat
analysis at all.
It seems that the most we can glean from PACE is that study design is essential to good science, and the flaws in this design were enough to doom its results from the start.
