Multidisciplinary rehabilitation treatment is not effective for ME/CFS: A review of the FatiGo trial, 2018, Vink & Vink-Niese

I came across the trial this paper is critiquing recently and want to highlight the lack of clinically significant improvement in objectively measured physical activity which the authors show in a table but make no comment on.

This is the trial:
Multidisciplinary rehabilitation treatment versus cognitive behavioural therapy for patients with chronic fatigue syndrome: a randomized controlled trial
Vos-Vromans et al.

Vink and Vink Niese do a detailed analysis of the data from the electronic activity monitors, and this is the bit that stood out for me, not just because Vos-Vromans report the results but don't include them in their conclusions, but just how feeble the results were. I've added in the cost in Euros per person from their economic analysis paper:

Treatment ...................Multidisciplinary rehab ............... CBT

Treatment Cost/person 8,989.06..................... 3,308.43
Societal cost/person 14,307.95 ..................... 8,845.71

Activity meter readings:
Baseline 206233.65 (40264.16).......................... 202033.66 (43379.41)

26 weeks 227283.24 (45698.55).......................210019.75(48068.09)
change from baseline ... up 10.2% ......................... up 3.9%
52 weeks 218214.41 (48564.30)........... .............215262.14 (57074.22)
change from baseline... up 5.8% ........................... up 6.5%
change from 26 weeks .. down 4.0% ....................... up 2.5%
__________________

Given that most definitions of ME/CFS require a level of fatigue that restricts daily activity to less than half what they were doing before, and given the average steps/day for women in the UK is around 5000, that would mean the trial participants are likely to be on less than 2500 steps/day. Given that they are able to attend lots of treatment sessions, they are probably at the upper end of ME/CFS functioning, so say they average 2000 steps/day at the start.
If we assume the changes in activity levels measured are a reasonable proxy for steps/day, what would this mean?

For someone who did the rehab:
They start on 2000 steps/day.
After 6 months 2204 steps/day,
At 12 months 2116 steps/day

For someone who did CBT:
They start on 2000 steps/day.
After 6 months, 2078 steps/day
After 12 months, 2139 steps/day.

So the net result from either treatment is that someone walking 2000 steps per day before treatment is now walking about 100 steps a day more. I think we can all agree that's nowhere near clinically significant. No wonder they don't even mention, let alone discuss or draw conclusions from this objective data in their papers.

But it gets worse, as Vink and Vink-Niese point out. A significant number of participants didn't wear the actometers at 6 months, and even less at 12 months, some of them saying it was because they couldn't travel to the clinic to collect and return the actometer. That seems to me such a huge red flag it makes even this data likely to be an over inflated result.
They presumably used the data from the whole cohort to calculate the average activity level at the start, and then only those who wore the actometer at the later stages, so we have no idea what the starting points were for those giving data at the end. What if, as seems likely, those who wore the actometers at the end where from the upper end of the activity levels at the start. So their average at the start may even have been higher than at the end.

To quote Vink and Vink-Niese

Yes, I know Vink and Vink Niese have drawn attention to all this already, and far more eloquently and completely than I can, but I have seen recently the subjective data from this trial being used to justify these treatments, so it's not over yet.

That's got that off my chest!

 

Yes, those very weak numbers are the best possible case scenario. Which is an appalling fact.