Alem Matthees analyses on released PACE data blast "recovery" claims - huge damage to PACE
- Thread starter user9876
- Start date
Julie Rehmeyer quotes him in her article:
https://www.statnews.com/2016/09/21/chronic-fatigue-syndrome-pace-trial/
https://www.statnews.com/2016/09/21/chronic-fatigue-syndrome-pace-trial/
- Messages
- 2,051
- Likes
- 10,097
For the avoidance of doubt I meant that he is ugly in spirit, I can honestly say I haven't given his picture a second glance. But I'm not going to apologize for disliking him.
this is big deal, authors of PACE published rebuttal, it's drivel.
http://www.ncbi.nlm.nih.gov/pubmed/27647810
http://www.ncbi.nlm.nih.gov/pubmed/27647810
I hear what you're saying, @A.B., but I also see @Valentijn's point.
PACE is actually the best quality evidence we have that these treatments DON'T work. Without it in the literature, someone else could come along and say "So far, things are looking good for these treatments. But no-one's done a really huge study with lots of patients (only some dodgy study that got retracted). Now we will do the definitive study - at a very high cost - to demonstrate their effectiveness beyond all doubt".
And off we go again...
PACE is actually the best quality evidence we have that these treatments DON'T work. Without it in the literature, someone else could come along and say "So far, things are looking good for these treatments. But no-one's done a really huge study with lots of patients (only some dodgy study that got retracted). Now we will do the definitive study - at a very high cost - to demonstrate their effectiveness beyond all doubt".
And off we go again...
Looking at Henrik Vogt's twitter feed, one might describe him as a "psychosocial activiist". He appears to be powerfully professionally - and personally - committed to the idea that a large portion of illnesses are psychosocial constructions. Lots of stuff on the "overmedicalisation" of illness.
For these kinds of true believers, CFS is the jewel in their crown, their finest example, because there's no biomarker and so no-one can make a strong case against a psychosocial interpretation. Of course he's going to hang on to it as long as he can.
It beggars belief when people like this - who don't suffer our illness but instead "use" it to support their arguments - criticise actual patients for "having an agenda". Mr Vogt, living with an illness every day certainly gives you an agenda, but that agenda is to fight for treatments that really work, that will help patients get back to full functioning. Its the only agenda that should be relevant to this endeavour. CFS does not exist so people can use it to make some sort of point - we are real people, with real suffering.
Patients should be heard on any issue that relates to their illness. They are the only ones whose interest is purely in getting better, with no COIs, financial, professional, or idealistic.
Edit: @Sasha, just read you message. Fair enough, I'll step off now.
For these kinds of true believers, CFS is the jewel in their crown, their finest example, because there's no biomarker and so no-one can make a strong case against a psychosocial interpretation. Of course he's going to hang on to it as long as he can.
It beggars belief when people like this - who don't suffer our illness but instead "use" it to support their arguments - criticise actual patients for "having an agenda". Mr Vogt, living with an illness every day certainly gives you an agenda, but that agenda is to fight for treatments that really work, that will help patients get back to full functioning. Its the only agenda that should be relevant to this endeavour. CFS does not exist so people can use it to make some sort of point - we are real people, with real suffering.
Patients should be heard on any issue that relates to their illness. They are the only ones whose interest is purely in getting better, with no COIs, financial, professional, or idealistic.
Edit: @Sasha, just read you message. Fair enough, I'll step off now.
Last edited:
They seem to be arguing that there is evidence for association, not mediation, but that this is should be assumed to be contemporaneous mediation.
Is this an attempt to respond to our Simon's letter in Lancet Psych?:
http://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(15)00085-1/abstract
Is this an attempt to respond to our Simon's letter in Lancet Psych?:
http://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(15)00085-1/abstract
- Messages
- 866
- Likes
- 3,847
@Esther12 Can you put that in laymans terms because I read the abstract and didn't have a clue what they were going on about.
Last edited:
Simon's letter is a fairly easy read. But if your brain is too fogged, here's a picture.
Imagine this is what the real data looked like (I just made this up, but its not that far from the actual patterns):
The "fearful cognitions" measure is the thing they think "mediates" the change in physical function scores (ie. it needs to happen first and only then will health improve). Notice how both measures actually change at the same time - it doesn't look as if the fear one changes first and the physical function measure later.
But look what happens if you only look at the timepoints that fit your theory:
Look how the figure "lies". It looks as though the change in fearful cognitions happened first and the change in the health (physical function) came later. The reality is that both changed together, but if you only have this info, you can end up concluding one caused a change in the other.
Imagine this is what the real data looked like (I just made this up, but its not that far from the actual patterns):
The "fearful cognitions" measure is the thing they think "mediates" the change in physical function scores (ie. it needs to happen first and only then will health improve). Notice how both measures actually change at the same time - it doesn't look as if the fear one changes first and the physical function measure later.
But look what happens if you only look at the timepoints that fit your theory:
Look how the figure "lies". It looks as though the change in fearful cognitions happened first and the change in the health (physical function) came later. The reality is that both changed together, but if you only have this info, you can end up concluding one caused a change in the other.
Last edited:
- Messages
- 2,157
- Likes
- 17,726
I get the impression that this mediation analysis coming out now may be coincidental not a direct attempt at rebuttal.
I understand it's a second paper on mediation analysis. I'm guessing some poor sod had the misfortune to sign up for a PhD and be given the PACE data to apply this weird incomprehensible form of analysis to.
I say poor sod because he/she wouldn't have known at the outset that the data came from a null trial, so attempting to show what is mediating an effect is on a hiding to nothing, because there is no effect to mediate.
I may have misunderstood the situation. It's 6am and I haven't slept much!
I understand it's a second paper on mediation analysis. I'm guessing some poor sod had the misfortune to sign up for a PhD and be given the PACE data to apply this weird incomprehensible form of analysis to.
I say poor sod because he/she wouldn't have known at the outset that the data came from a null trial, so attempting to show what is mediating an effect is on a hiding to nothing, because there is no effect to mediate.
I may have misunderstood the situation. It's 6am and I haven't slept much!
Going back to the new article these guys just wrote on the mediation stuff, I'm not a statistician, so my interpretation might not be perfect. But I was struck by this bit:
This is essentially saying pretty much what I said above with the pictures. That there's no real evidence that the change in the mediator (fear avoidance beliefs, etc.) preceded the change in the outcome (self-reported physical function etc.). They are conceding that if you want to claim causation, you really need to show that one did actually precede the other. And that they couldn't show that - so causation can't be inferred. So my conclusion from this paper is "Move along folks, nothing to see here"
This is essentially saying pretty much what I said above with the pictures. That there's no real evidence that the change in the mediator (fear avoidance beliefs, etc.) preceded the change in the outcome (self-reported physical function etc.). They are conceding that if you want to claim causation, you really need to show that one did actually precede the other. And that they couldn't show that - so causation can't be inferred. So my conclusion from this paper is "Move along folks, nothing to see here"
The PACE authors are likely so invested in the explanatory power of their hypothesis (the BPS model) that they turn to methodological factors to explain their null result. Somehow, in their minds, the applied methodology failed to extract the "truth" from the data, and so their methods of statistical analysis needs refining.