A brief, comprehensive measure of post-exertional malaise, 2025, Jason and Chee

[Mij]

I thought Table 4, effectiveness of pacing numbers interesting. I eliminated delayed PEM completely by pacing for years now.

This is entirely circular. It says that this questionnaire measures PEM because it measures what we say that PEM is.

They clearly didn't read my answers from previous questionnaires. I'm no longer spending my limited cognitive energy answering them.

 

[Hutan]

Next day soreness or fatigue after non-strenuous, everyday activities.
Mentally tired after the slightest effort.
Physically drained or sick after mild activity.
Dead, heavy feeling after starting to exercise.
Minimum exercise makes you physically tired.

Those items from Table 6 are almost a perfect list of things I want people to understand are not PEM. I think this tool is just going to confuse people.

 

[Simon M]

I thought the PEM duration work by Lenny Jason was incredibly useful. I'm not sure about the rest. To me, what we really need is an instrument that researchers can use to identify if people have PEM as it's the cardinal symptom of this disease.

I suspect that's not going to happen unless we do it, or initiate ithere.

This is what DecodeME used in its questionnaire, developed by people who live with the illness because there was nothing decent out there. I think it's pretty good, and more useful than the questionnaire discussed above to identify people who do have pem.

Symptoms after effort or activity

12. In the last 6 months, what happens to your symptoms after you do more physical or mental activity than usual (exceed your energy limit)? If you pace your energy, we want you to think about what would have happened if you didn't. Please only choose ONE answer.

 My symptoms (such as pain, fatigue or feeling out-of-sorts) get worse, or I get new symptoms, and this reduces how much I can do

 My symptoms either stay the same or improve (Skip to Question 14)

13. In the last 6 months, after you have done more physical or mental activity than usual (exceeded your energy limit), how long does the change in your symptoms usually last? If you pace your energy, we want you to think about what would have happened if you didn't. Please only choose ONE answer.

 The change in my symptoms lasts a long time, which can be more than 24 hours

 I bounce back straight away or my symptoms don't last very long given the effort I just made

I wonder if the final question, which uses my italics need more guidance. I’m concerned that exertion intolerance, seen in many illnesses after physical effort, would be captured by this. The Lenny Jason date suggested 12 hours would be a reasonable minimum, but we at least need to replicate that and There is always a danger with any threshold of losing milder cases.

 

[JemPD]

Minimum exercise makes you physically

So anyone who is normally sedentary. Is there any wonder that the deconditioning theory still rages on

Those items from Table 6 are almost a perfect list of things I want people to understand are not PEM. I think this tool is just going to confuse people.

Exactly.

Nearly everyone I know tells me they have brain fog now. Soon everyone will be telling me about their “PEM” when they feel knackered after a day’s work or a brisk walk.

 

[Kitty]

I wonder if the final question, which uses my italics need more guidance. I’m concerned that exertion intolerance, seen in many illnesses after physical effort, would be captured by this. The Lenny Jason date suggested 12 hours would be a reasonable minimum, but we at least need to replicate that and There is always a danger with any threshold of losing milder cases.

Yes, it's a good point. But even when my illness was at its mildest, I don't think I'd ever have ticked "I bounce straight back". I woke up feeling as if I had a virus or a hangover, but the worst of it only lasted around three hours.

I thought it was quite a clever phrase, as bouncing back is likely to be a distant memory in any severity of ME/CFS. If you asked people who're mild enough to be able to work how old they feel, I suspect quite a lot would go for the "80 – 90" option.

 

[Trish]

I doubt the idea that severity of ME/CFS correlates with duration of PEM.

Spoiler: My experience

Even when my ME/CFS was mild enough for me to teach 15 hours a week, plus at least equivalent prep time and caring for family, my crashes put me to bed for days, and I needed a week or two off work. The length and severity of my PEM is about the same now. I suspect the duration of PEM episodes depends more on the extent to which you push beyond your current PEM threshold. The difference for me is that now I'm severe physically, the amount of physical exertion that makes me crash is far less than it was when I was mild, and things like sitting up for too long and sensory stimuli contribute more noticably to whether I crash.

 

[Utsikt]

I thought the PEM duration work by Lenny Jason was incredibly useful. I'm not sure about the rest. To me, what we really need is an instrument that researchers can use to identify if people have PEM as it's the cardinal symptom of this disease.

I suspect that's not going to happen unless we do it, or initiate ithere.

This is what DecodeME used in its questionnaire, developed by people who live with the illness because there was nothing decent out there. I think it's pretty good, and more useful than the questionnaire discussed above to identify people who do have pem.

Symptoms after effort or activity

12. In the last 6 months, what happens to your symptoms after you do more physical or mental activity than usual (exceed your energy limit)? If you pace your energy, we want you to think about what would have happened if you didn't. Please only choose ONE answer.

 My symptoms (such as pain, fatigue or feeling out-of-sorts) get worse, or I get new symptoms, and this reduces how much I can do

 My symptoms either stay the same or improve (Skip to Question 14)

13. In the last 6 months, after you have done more physical or mental activity than usual (exceeded your energy limit), how long does the change in your symptoms usually last? If you pace your energy, we want you to think about what would have happened if you didn't. Please only choose ONE answer.

 The change in my symptoms lasts a long time, which can be more than 24 hours

 I bounce back straight away or my symptoms don't last very long given the effort I just made

I wonder if the final question, which uses my italics need more guidance. I’m concerned that exertion intolerance, seen in many illnesses after physical effort, would be captured by this. The Lenny Jason date suggested 12 hours would be a reasonable minimum, but we at least need to replicate that and There is always a danger with any threshold of losing milder cases.

I agree that this would probably also capture people that do not have PEM.

 

[Mij]

Table 6, symptoms of PEM

"Problems thinking"

Thinking is a mental process that allows you to learn, reason, and make decisions. I'm making decisions and reasoning just fine during PEM, it's just that I don't want to talk or interact with anyone atm.

 

[Mij]

Nearly everyone I know tells me they have brain fog now. Soon everyone will be telling me about their “PEM” when they feel knackered after a day’s work or a brisk walk.

Yes, like my dental hygienist who told me she has a few patients with CFS and Long Covid who are having difficulty getting diagnosed, and that she thinks she might have CFS. It was hard to explain to her while she's cleaning my teeth, but I did get a word or two in between polishing and fluoride treatment to explain a little. No I told her, it has an infectious onset (even though for some there is no obvious onset) but my appointment was over by then.