Trial By Error: My 2011 Exchange with White et al about Case Definition

[Andy]

My first exchange of views with the PACE authors involved the issue of case definition–the criteria used to identify the illness they called chronic fatigue syndrome. This exchange took place courtesy of The New York Times, not long after The Lancet published the results of the PACE trial. In March, 2011, the Times ran a piece about the role of disease criteria in epidemiology, in which I analyzed the PACE trial’s use of the problematic fatigue-based Oxford criteria. (This was actually my second piece involving PACE; the first, a news story, was a piece of crap because I took the study at face value, having never heard of it before the findings were announced.)

After my case definition story ran, I received an e-mail from Professor Michael Sharpe, requesting a correction and–if I remember accurately–offering to send me a copy of the paper. Professor Sharpe’s complaint was that I had not mentioned the PACE trial’s sub-group analyses of participants who had met two other case definitions. I forwarded Professor Sharpe’s note to my editor, who agreed to run a letter from the PACE authors, along with my response. I thought it would be interesting to revisit that exchange, so I’ve posted it below.

http://www.virology.ws/2019/12/31/t...hange-with-white-et-al-about-case-definition/

 

[chrisb]

The patients in this trial had a disabling chronic illness in which fatigue was their main symptom and for which no alternative had been found; that is the definition of the syndrome used in Britain.

I have no idea what Sharpe meant in that response to DT's article in the NYTimes. Does anyone? No alternative what?

 

[Andy]

The patients in this trial had a disabling chronic illness in which fatigue was their main symptom and for which no alternative had been found; that is the definition of the syndrome used in Britain.

I have no idea what Sharpe meant in that response to DT's article in the NYTimes. Does anyone? No alternative what?

I would assume it's missing the word explanation, as in

"..and for which no alternative [explanation] had been found.."

so therefore, in my opinion, idiopathic chronic fatigue.

 

[Barry]

As a general rule, clinical case definitions are broader because you want to make sure everyone who might have the condition gets medical care, even if they are eventually determined to be suffering from something else. Research case definitions can be tighter because you want a more homogeneous group to reduce the possibility that extraneous factors might muddy the clarity of the results.

I hadn't properly appreciated that distinction, but it makes perfect sense, and is crucial. In the clinical case you don't want to miss people even with marginal diagnoses who it might be possible to still help. In the other case you need to avoid ambiguous diagnoses, in order to avoid ambiguous trial findings.

 

[dave30th]

I would assume it's missing the word explanation,

That's right. That's how it originally appeared when they sent the letter in. I never noticed before that it was likely missing a word.

 

[dave30th]

I hadn't properly appreciated that distinction, but it makes perfect sense, and is crucial. In the clinical case you don't want to miss people even with marginal diagnoses who it might be possible to still help. In the the other case you need to avoid ambiguous diagnoses, in order to avoid ambiguous trial findings.

Exactly. So using a clinical case definition in research can be problematic.

 

[Barry]

The patients in this trial had a disabling chronic illness in which fatigue was their main symptom and for which no alternative had been found; that is the definition of the syndrome used in Britain.

I have no idea what Sharpe meant in that response to DT's article in the NYTimes. Does anyone? No alternative what?

I took it, given the context, to mean no alternative illness.

 

[rvallee]

however the illness is defined

Coming from people who loudly self-proclaim themselves to be "top researchers" in this field, this is just pathetic. They simply have no integrity and even less diligence in their work beyond the appearance and language of science, with none of the substance.

However, much more fault lies in people who allow, approve, fund and defend this charade, even worse that identical garbage is still, to this day, richly funded and promoted as having any scientific value. You can fault the con man for fooling you once. Just the once. After that, responsibility lies in those who gave line-item budget to the con.

 

[Forbin]

The patients in this trial had a disabling chronic illness in which fatigue was their main symptom and for which no alternative had been found; that is the definition of the syndrome used in Britain.

Using "alternative explanation" doesn't make sense unless some other explanation had been mentioned earlier in the letter. None was. I think it's probably a "typo" in which the word "alternative" was used instead of "explanation."

"The patients in this trial had a disabling chronic illness in which fatigue was their main symptom and for which no explanation had been found; that is the definition of the syndrome used in Britain.