What do people think of SF-36?

[Jonathan Edwards]

This has come up in the context of the Research Strategy Working Group.
I would be interested to know the views here.

 

[rvallee]

Very generic and has its uses. Unfortunately the main problem is that it's misused out of disbelief or ideological or political motivations, which are rampant throughout healthcare. Research using SF-36 has consistently validated the horrible quality of life of pwME, including the physical dimensions, but any mention of this outside our bubble gets mocked or ridiculed as fake.

Of all the questionnaires, it's frankly probably the most useful one, but it can be interpreted willy-nilly, cancelling any usefulness. There is unlimited ability to simply decide to attribute the responses to various other imagined causes. The problem is rarely with the instruments themselves, it's a context that encourages misuse in some arbitrary cases that make it switch back-and-forth between a valid instrument, and a "hot take", as I've seen recently commented on in a medical forum about our extremely low scores.

So it's a standard generic instrument, but it's used arbitrarily and we can't control of influence that. There is not much to say beyond that, it's misused no matter what because in the end beliefs trump everything.

Everything is in the eye of the beholder, even reality. The lying eyes are the problem.

 

[Trish]

I'm with Graham in his analysis on his video about the SF-36 physical functioning questionnaire.
See his video:

Discussed here:
https://www.s4me.info/threads/me-analysis-the-3-pace-videos-factsheet.6106/

The key point is it's all too easy for therapists to persuade people to interpret their level of difficulty with an activity differently. Similarly I think wishful thinking for people on drug trials could move people significantly up the scale.

Also the PACE results of some apparent between group differences on SF-36PF were not matched by parallel differences in the objective tests.

And for people with severe and very severe ME/CFS people are likely to score close to zero on all the activities right across the range of disease severity from extremely severe to borderline moderate/severe, so there's no way it can detect the very significant improvement or worsening at the bottom end.

On the other hand, it's better than the Chalder scale which as far as I'm concerned is far worse than useless.

If it is used, I think it would only be realistic if the clinically significant difference were pre set at about 20 on the 100 point scale, to allow for wishful thinking. I think at the moment it's usually set at about 7 which only requires you to change a couple of the items slightly.

There's another questionnaire I came across that seemed better. I'll see if I can find it.

 

[Trish]

Also I forgot to raise the probem that it's not designed for pwME, so only asks if you can do something, not whether you can do it every day or several times a day or what else you are doing that day. In other words, it takes no account of the cumulative effect of the whole day's activities. That's a major drawback, I think.

 

[RedFox]

The SF36 is good enough to be trustworthy in a blinded trial. It's generic but that's OK because ME has such a broad impact on our functioning.

The other tool we have is the DSQ. The SF-36 uses ability to do tasks as a watermark, and the DSQ uses symptoms. My gut says ability to do activities is better. It's more concrete and less variable day-to-day. The DSQ doesn't consider the fact that pacing can reduce symptoms a lot, or that it can be worth doing a bit more to feel a little worse. But SF-36 doesn't care how you feel.

In ME, your symptoms get worse the more you do. There's a tradeoff between activity and symptoms, at least until you completely crash. You can imagine a graph with activity on X axis, and degree of symptoms on the Y axis, and symptoms increasing as activity increases. If there's a medicine that shifts the graph towards less symptoms (down and to the right), some people will become more active at their old symptom level, others will prefer to experience symptom relief, and most will take some of both. (This is analogous to what people do when their income increases. How much of the increase will they use to buy new things, and how much will they invest?)

 

[TigerLilea]

Personally I think these types of questionnaires are meaningless. Limiting questions to "the last 4 weeks" for someone who has had ME (or whatever health condition) for years or decades doesn't provide accurate information. They are a waste of time and don't give accurate meaningful information.

For instance:

PHYSICAL HEALTH PROBLEMS: During the past 4 weeks, have you had any of the following problems with your work or other regular daily activities as a result of your physical health?

Cut down the amount of time you spent on work or other activities
Yes No

For this I would answer "No". The reason being, I had to cut down the amount of time I spent on work or other activities back in 2021. But by answering "no" to this question, it leaves the impression that I'm able to work or engage in my regular daily activities.

 

[RedFox]

Also I forgot to raise the probem that it's not designed for pwME, so only asks if you can do something, not whether you can do it every day or several times a day or what else you are doing that day. In other words, it takes no account of the cumulative effect of the whole day's activities. That's a major drawback, I think.

This is crucial for developing scales for ME research. It must be multidimensional. We need ways of asking:

• Can you do this activity always, on good days, or never?
• Can you do it repeatedly, or do you need time to recover? How long?
  
• How incapacitated are you while recovering?
• How miserable are you while recovering?

There's multiple parameters to PEM: The level that triggers it, the length of the delay, the speed of the decline into PEM, its severity or "depth", and the speed of recovery.

 

[Kitty]

I've never heard of it, at least by that name—I'll look it up.

 

[DigitalDrifter]

It doesn't measure PEM threshold, PEM severity, or PEM duration. I think it is very ill suited for measuring ME.

 

[Sean]

I think that self-report questionnaires in general are so inherently problematic that they will more often than not be misleading. Look how often they disagree with objective or blinded measures.

I never know how to answer them. Way too vague and arbitrary, and often simply irrelevant, to be genuinely useful and safe. I am getting to the point where I will simply refuse to answer them.

They may or may not have some modest limited value in aggregate, for large groups or population level studies. But for individual assessments I think they simply should not be used.

Their main value is in teaching us how hopelessly contaminated such approaches are with bias and confounders, and the critical importance of adequate control in clinical trials.

 

[Milo]

Self-report instrument that is not specific to ME. Some of the questions can be ambiguous and subject to interpretation.

One section the SF-36 pertains to general health. Are you healthy, and are you just as healthy as anybody else around you? This is a tricky question with a chronic illness. I very seldom get any viruses or infections- I have not been hospitalized. I get by in terms of my activities of daily living. So am I healthy? I always say that my health is poor to very poor. Others may interpret and answer it differently. How do you explain to someone that you are sick enough to be on disability insurance but then you are generally healthy in the sense that you do not catch a virus every other week (likely because you are for the most part not bound to meet many people in a week)

Another section about mental health asks how much have you felt worn out- what is that supposed to mean? I feel worn out in the physical point of view. If I answer very worn out the test is going to skew my mental health results.

The questions asked for SF-36 and generally with other standardized questionnaires do not measure anything specific other than the patient's opinion. It is not a questionnaire that you'd administer every 3 months to assess change in status. So why?

 

[RedFox]

One section the SF-36 pertains to general health. Are you healthy, and are you just as healthy as anybody else around you? This is a tricky question with a chronic illness. I very seldom get any viruses or infections- I have not been hospitalized. I get by in terms of my activities of daily living. So am I healthy? I always say that my health is poor to very poor. Others may interpret and answer it differently. How do you explain to someone that you are sick enough to be on disability insurance but then you are generally healthy in the sense that you do not catch a virus every other week (likely because you are for the most part not bound to meet many people in a week)

Some people feel pressured to use a definition of health that conforms to social biases, where life-threatening, well-understood, stable, visible, and physical conditions are considered more legitimate than their opposites. Others would share my view. My health is obviously poor because I often feel unwell and I can't do many things I want to. The specific wording is indeed a stumbling block.

 

[RedFox]

The WHODAS 2.0 fills a similar role as the SF-36.

 

[Ravn]

For all the reasons others have already mentioned I don't think the SF-36 is meaningful in ME, not entirely surprising since it wasn't developed with ME in mind.

The Norwegians are developing and thoroughly testing a questionnaire to assess function specifically in pwME and their latest draft looks promising. May be worth contacting them to see where they're at. Discussed here:

https://www.s4me.info/threads/norwa...ctioning-in-pwme-cfs-open-for-feedback.24995/

 

[Jaybee00]

For me the ~10 or so physical function (PF) questions are pretty useless because i have no problems climbing a flight of stairs, lifting a bag, walking a bunch, etc. I score closer to a normie here.

I think the ~4 vitality questions are probably useful for everyone with MECFS. In contrast to the PF, I score closer to a non-living entity/vegetable here. If you see a positive change in the vitality scores then something good is probably happening. Note that these 4 questions are about energy level per se, not about depression, etc. The vitality questions are in the section called ENERGY AND EMOTIONS, which does feature several other questions that specifically address depression and anxiety. So I endorse the vitality questions within the E&E section, but not necessarily all the questions in the E&E section.

“
SF-36 vitality scale
The vitality scale assesses energy and fatigue to capture differences in subjective well-being. It asks “How much of the time during the past 4 weeks did you have a lot of energy?” “...have you felt full of life?” “...did you feel worn out?” and “...did you feel tired?” Respondents choose from a five-point scale ranging from none of the time to all of the time. Standardized scores range from 0 to 100, with lower scores indicating greater fatigue. [12]. The SF-36 has well established internal consistency, reliability, content validity, construct validity, and criterion-related validity, having been tested in a variety of population samples [13]. Scores ≤45 have been established as representing clinically significant fatigue [14].”


From https://www.researchgate.net/profil...ntory-in-assessing-cancer-related-fatigue.pdf

 

[Trish]

@Jonathan Edwards do you mean the whole SF36 questionnaire which includes mental health, or just the 10 question Physical Functioning section which is commonly used as an outcome measure in trials like PACE?

 

[Jaybee00]

SF questions reviews—my commentary

Q1&2 Fine
Q3-12 PF Maybe not great Qs for mild/moderate patients
Q13-16–Ok but as mentioned above the 4 week timeframe not good.
Q17-20 MH (mental health) questions-so maybe not appropriate
Q21-22 pain questions—ok but also 4 weeks
Q23-vitality—good
Q24-26 MH
Q27 vitality-good
Q28 MH
Q29 vitality-good
Q30 MH
Q31 Vitality—good
Q32 This one is OK
Q33 Dumb for MECFS
Q34 Dumb for MECFS
Q35 ?—hmmm—actually probably a good question—probably differentiates progressive MECFS from stable MECFS or pessimists from optimists.
Q36 Dumb for MECFS

link https://www.dochub.com/jsfiller-mob...&loader=tips#b2ffdaec71cb4f45a1f0bc869b7c1b60

 

[Milo]

Here is what we have learnt throughout the last decade from SF-36.
1) Patients are sick
2) Mental health is good
3) PwME can be more disabled as patients with MS

And here is what I have learnt from filling out SF-36:
1) The quicker you get through it, the faster it will be over. Answer quickly, the answers don't really change.
2) SF-36 is usually accompanied by other questionnaires, some longer than others. Most if not all of them do not convey what I want to say. And yet my responses (or ours, collectively) are analyzed to minutiae, looking for p<0.05 And yet, SF-36 does not change anything for pwME. We are still sick. Very, very few of us ever cross over from disabled back to healthy again.
3) The definition of insanity is doing the same things over and over and expecting different results. SF-36 is not changing. We are still sick.

 

[FMMM1]

Very generic and has its uses. Unfortunately the main problem is that it's misused out of disbelief or ideological or political motivations, which are rampant throughout healthcare. Research using SF-36 has consistently validated the horrible quality of life of pwME, including the physical dimensions, but any mention of this outside our bubble gets mocked or ridiculed as fake.

Of all the questionnaires, it's frankly probably the most useful one, but it can be interpreted willy-nilly, cancelling any usefulness. There is unlimited ability to simply decide to attribute the responses to various other imagined causes. The problem is rarely with the instruments themselves, it's a context that encourages misuse in some arbitrary cases that make it switch back-and-forth between a valid instrument, and a "hot take", as I've seen recently commented on in a medical forum about our extremely low scores.

So it's a standard generic instrument, but it's used arbitrarily and we can't control of influence that. There is not much to say beyond that, it's misused no matter what because in the end beliefs trump everything.

Everything is in the eye of the beholder, even reality. The lying eyes are the problem.

Yea sounds like a case of moving to objective outcome indicators where possible i.e. subjective outcome indicators should only be used where objectives ones are not available --- so what does SF36 measure and is there an objective way to measure it --- if so then don't use SF36 for that objectively measurable element.

 

[FMMM1]

Self-report instrument that is not specific to ME. Some of the questions can be ambiguous and subject to interpretation.

One section the SF-36 pertains to general health. Are you healthy, and are you just as healthy as anybody else around you? This is a tricky question with a chronic illness. I very seldom get any viruses or infections- I have not been hospitalized. I get by in terms of my activities of daily living. So am I healthy? I always say that my health is poor to very poor. Others may interpret and answer it differently. How do you explain to someone that you are sick enough to be on disability insurance but then you are generally healthy in the sense that you do not catch a virus every other week (likely because you are for the most part not bound to meet many people in a week)

Another section about mental health asks how much have you felt worn out- what is that supposed to mean? I feel worn out in the physical point of view. If I answer very worn out the test is going to skew my mental health results.

The questions asked for SF-36 and generally with other standardized questionnaires do not measure anything specific other than the patient's opinion. It is not a questionnaire that you'd administer every 3 months to assess change in status. So why?

Yea recall an assessment of activity via questionnaire and actimetry --- questionnaire was unreliable.