PACE Trial and PACE Trial Protocol

Graham

Senior Moment
Messages
5,188
Location
Sussex, UK
What about just adding this as a final scene in the PACE race? Is it clear enough do you think?

end&pelican.png
 

alex3619

Senior Member
Messages
13,810
Location
Logan, Queensland, Australia
Hi Graham, I like that but it was confusing for a second that you are using the same icon at the start and at the safe crossing point. Maybe a different or modified graphic would be better? Maybe a "Walk/Don't Walk" sign? Or just "Don't Walk"? Bye, Alex
 

Bob

Senior Member
Messages
16,455
Location
England (south coast)
Hi Graham, I like that but it was confusing for a second that you are using the same icon at the start and at the safe crossing point. Maybe a different or modified graphic would be better? Maybe a "Walk/Don't Walk" sign? Or just "Don't Walk"? Bye, Alex

It might not be confusing when you watch the whole video, because it would be more obvious that the first traffic light is on the start line.
 

Graham

Senior Moment
Messages
5,188
Location
Sussex, UK
I'm still open to suggestions. It takes a long time to come up with something good, and then it's generally so simple you wonder why you didn't think of it in the first place.

I did think about the walk/don't walk green man/red man idea, but it looked as if you were just signalling the end of the race and they had to stop walking.

Are you sure a pelican crossing isn't 450m across? It feels like it some days.
 

Dolphin

Senior Member
Messages
17,567
What about just adding this as a final scene in the PACE race? Is it clear enough do you think?

View attachment 3545
(Not serious)
I think I may have watched too many South Park cartoons and the like: I can't help myself thinking of one or more other cartoons where a car comes along, runs into the slow movers, and we see lots of blood! :)
 

Bob

Senior Member
Messages
16,455
Location
England (south coast)
If anyone has been looking for studies that define ceiling effects for SF-36 Physical Function, for chronically ill patients, I've come across a paper...

Individual-patient monitoring in clinical practice: are available health status surveys adequate?
C A McHorney and A R Tarlov
This is found on pages 293-307 inside a journal:
Quality of Life Research volume 4 1995
(Publisher = Oxford: Rapid Communications of Oxford)

The results are based on "The MOS 36-Item Short-Form Health Survey (SF-36)", a study of 'chronically ill patients'... So it does not related to the general population, but just chronically ill patients.

Here's the details:

Table A.4.
Floor and ceiling effects for the SF-36 survey (n=3445)
SF-36 physical functioning
Floor effect = 1%
Ceiling effect = 19%
(Source: McHorney CA, Ware JE, Lu JFR, et al., The MOS 36-Item Short Form Survey (SF-36). III. Tests of data quality, scaling assumptions and reliability across diverse patient groups. Med Care 1994; 32: 40-66)


Also of interest, is that it gives a 'statistically significant' score for an individual patient's health, for example as the questionnaire might be used in a clinical setting, as 23 points for SF-36 PF. Note that this does not apply to the PACE Trial study though, because it was looking at the results for a large number of patients. It's only relevant when looking at one individual patient to assess their scores, such as in a clinical setting.

I assume that this would relate to any patient, but the results seem to be based on the MOS study.


Edit: I've updated/corrected this post, as per Dolphin's next post.
 

Dolphin

Senior Member
Messages
17,567
If anyone has been looking for studies that define ceiling effects for SF-36 PF, I've come across a paper...

Individual-patient monitoring in clinical practice: are available health status surveys adequate?
C A McHorney and A R Tarlov
This is found on pages 293-307 inside a journal:
Quality of Life Research volume 4 1995
(Publisher = Oxford: Rapid Communications of Oxford)

Here's the details:

Table A.4.
Floor and ceiling effects for the SF-36 survey (n=3445)
SF-36 physical functioning
Floor effect = 1%
Ceiling effect = 19%
(Source: McHorney CA, Ware JE, Lu JFR, et al., The MOS 36-Item Short Form Survey (SF-36). III. Tests of data quality, scaling assumptions and reliability across diverse patient groups. Med Care 1994; 32: 40-66)

Also of interest, is that it gives a 'statistically significant' score for an individual patient's health, for example as the questionnaire might be used in a clinical setting, as 23 points for SF-36 PF. Note that this does not apply to the PACE Trial study though, because it was looking at the results for a large number of patients. It's only relevant when looking at one individual patient to assess their scores, such as in a clinical setting.
Interesting. However, they're not population norms from what I can see. People in "diverse patient groups" likely to be less healthy than individuals who aren't patients.

If one looks at:
Velanovich V. Behavior and analysis of 36-item short-form health survey data for surgical quality-of-life research. Arch Surg. 2007;142(5):473-478.
Free at: http://archsurg.jamanetwork.com/article.aspx?volume=142&issue=5&page=473

In Table 2, it gives US population norms.
38.7% get 100/100 for SF-36 PF.
 

Bob

Senior Member
Messages
16,455
Location
England (south coast)
Interesting. However, they're not population norms from what I can see. People in "diverse patient groups" likely to be less healthy than individuals who aren't patients.

If one looks at:
Velanovich V. Behavior and analysis of 36-item short-form health survey data for surgical quality-of-life research. Arch Surg. 2007;142(5):473-478.
Free at: http://archsurg.jamanetwork.com/article.aspx?volume=142&issue=5&page=473

In Table 2, it gives US population norms.
38.7% get 100/100 for SF-36 PF.

Ah, yes, you are right Dolphin. Sorry about that!...
The paper wasn't as clear as it could have been.
The results are based on "The MOS 36-Item Short-Form Health Survey (SF-36)", which was a study of 'chronically ill patients'...

I'll add that info to my post, and make corrections.

The Health Survey for England also states that 36% of the adult population have a score of 100 (very similar to the US norms that you've highlighted):
http://www.archive.official-documents.co.uk/document/doh/survey96/ehch5.htm
 

Bob

Senior Member
Messages
16,455
Location
England (south coast)
I've updated/corrected my previous post, re ceiling effects. It applies to chronically ill patients, not the general population.
Also, the clinical significance for individual scores seems to be based on the MOS survey, but I assume that's relevant for all patients.
 

Graham

Senior Moment
Messages
5,188
Location
Sussex, UK
(Not serious)
I think I may have watched too many South Park cartoons and the like: I can't help myself thinking of one or more other cartoons where a car comes along, runs into the slow movers, and we see lots of blood! :)

That's it Dolphin! In the final scene a care mows down the three figures that didn't make it, and in their dying breaths the GET patient gasps "See, I told you it wasn't working!"
 

biophile

Places I'd rather be.
Messages
8,977
As previously posted, Q&A #25 of the PACE FAQ2 claims that the patient charity advising them (AfME) agreed that it would be "sensible" to drop followup actigraphy (http://www.pacetrial.org/faq/faq2.html). What else can be said other than WTF? I hope they don't repeat that mistake again.

Anyway, I also found an old post from the Co-Cure archives where White states that both AfME and ME Association "supported" PACE's decision not to use the Canadian criteria (https://listserv.nodak.edu/cgi-bin/wa.exe?A2=ind0410A&L=CO-CURE&P=R46&I=-3). White claims the main reasons were: 1) would have cost an additional $100K to implement which the MRC were unwilling to spend "without a convincing scientific argument to support it"; 2) the extra investigations were unnecessary and "unethical" eg tilt table testing; 3) CCC are clinical criteria not research criteria.

I wonder if these organizations are proud of these earlier recommendations, especially now that they have both spoken out against the trial results? I wonder if Chris Clark from AfME still stands by his 2003 statement that "This study should end the debate about the value of pacing." (https://listserv.nodak.edu/cgi-bin/wa.exe?A2=ind0305C&L=CO-CURE&P=R85&I=-3)
 

Marco

Grrrrrrr!
Messages
2,386
Location
Near Cognac, France
I think I may have watched too many South Park cartoons and the like: I can't help myself thinking of one or more other cartoons where a car comes along, runs into the slow movers, and we see lots of blood!

We could have a Cartmanesque voiceover going "Oh my God! They killed Kenny! ...You b**tards!" :)
 

Dolphin

Senior Member
Messages
17,567

oceanblue

Guest
Messages
1,383
Location
UK
I wonder if these organizations are proud of these earlier recommendations, especially now that they have both spoken out against the trial results? I wonder if Chris Clark from AfME still stands by his 2003 statement that "This study should end the debate about the value of pacing." (https://listserv.nodak.edu/cgi-bin/wa.exe?A2=ind0305C&L=CO-CURE&P=R85&I=-3)
Personally, I think it was a very good idea for AfME to support formal testing of Pacing alongside CBT/GET. But such a shame they screwed it up by using a form of Pacing with a limit of 75% of available energy (reduced by PACE to 70% for the trial) - which I suspect is used by no one in the real worldand pretty-well doomed that form of pacing to failure. As I've mentioned before, nobody at AfME was able to explain to me the logic for the 75% rule.

Also, at the time PACE was being planned, the CCC were still quite new, were indeed specifically for clinical not research use and had never been used in research trials at that point. I would have settled for Fukuda criteria alongside Oxford, but I have grave reservations about they way they implemented symptom counting in Fukuda, especially as over 2/3 for Oxford-criteria patients were given a Fukuda classification.The Trial paper gives no details about exactly how symptoms were measured for diagnosis.
 

Dolphin

Senior Member
Messages
17,567
Apologies if this has been done before - don't remember it:
Ross RM, Murthy JN, Wollak ID, Jackson AS. The six minute walk test accurately estimates mean peak oxygen uptake. BMC Pulm Med. 2010 May 26;10:31. Free at: http://www.biomedcentral.com/1471-2466/10/31
contains this equation:
Mean Peak VO2 (ml / kg /min) = 4.948 + (0.023*Mean 6 MWD (meters))

Plugging in the GET results from completion of the PACE Trial, it would be 13.665ml / kg /min! (not very good!)
 

oceanblue

Guest
Messages
1,383
Location
UK
Apologies if this has been done before - don't remember it:

contains this equation:
Mean Peak VO2 (ml / kg /min) = 4.948 + (0.023*Mean 6 MWD (meters))

Plugging in the GET results from completion of the PACE Trial, it would be 13.665ml / kg /min! (not very good!)
Interesting! Though doesn't really fit with actual VO2max data on CFS patients :( , which have means from 20 ml/kg/min to around 30, as discussed here: Is there any evidence that deconditioning alone causes pain and fatigue? I think the BMC study was only conducted on cardiopulmonary patients.
 

Dolphin

Senior Member
Messages
17,567
Interesting! Though doesn't really fit with actual VO2max data on CFS patients :( , which have means from 20 ml/kg/min to around 30, as discussed here: Is there any evidence that deconditioning alone causes pain and fatigue? I think the BMC study was only conducted on cardiopulmonary patients.
Yes, perhaps the extrapolation to CFS patients can't be made from these figures on closer inspection. The title didn't suggest the equation was specific to cardiopulmonary patients but that might be due to the journal.
 
Back