Tools

Post-exertional malaise questionnaire

DSQ-PEM: the DePaul post-exertional malaise short form

Post-exertional malaise (PEM) is a worsening of symptoms after physical or mental effort that is out of proportion to the effort. It is often delayed by hours or days, and recovery can take hours, days, weeks or longer. It is a core symptom of ME/CFS: the NICE guideline requires it before ME/CFS is diagnosed.

It also matters practically. If PEM is present, pushing through or steadily increasing activity can make things worse. Spotting it early changes how you approach recovery.

The DSQ-PEM is a 10-question short form of the DePaul Symptom Questionnaire, published by Cotler and colleagues in 2018. Five symptoms are rated for how often and how severely they occurred over the past six months. Five more questions ask about triggers and recovery time. In an earlier DePaul study of 704 people with ME/CFS, 97% reported at least one of the five symptoms at least half the time and at moderate severity or worse; in the 2018 study it was 99%. It takes about 3 minutes.

This tool sits between the 4-question DSQ-Brief (a general ME/CFS screen) and the full DSQ-2 (a complete symptom assessment). If you want to check whether your post-activity pattern looks like PEM, this is the one to take.

This is not a diagnostic tool. A positive result means your reported pattern is consistent with PEM, not that you have ME/CFS or any other condition. Discuss your results with your doctor. Based on: Cotler J, Holtzman C, Dudun C, Jason LA. A Brief Questionnaire to Assess Post-Exertional Malaise. Diagnostics. 2018;8(3):66. DePaul University makes the DSQ instruments free to use.

Part 1: Symptoms over the past six months

Rate how often you have had each symptom and how severe it has been, over the past six months. If a symptom is absent, choose "None of the time" and severity will be set for you.

A dead, heavy feeling after starting to exercise

How often
How severe

Next-day soreness or fatigue after non-strenuous, everyday activities

How often
How severe

Mentally tired after the slightest effort

How often
How severe

A minimum of exercise makes you physically tired

How often
How severe

Physically drained or sick after mild activity

How often
How severe

Part 2: Recovery and triggers

If you were to become exhausted after actively participating in extracurricular activities, sports, or outings with friends, would you recover within an hour or two after the activity ended?

Do you experience a worsening of your fatigue / energy-related illness after engaging in minimal physical effort?

Do you experience a worsening of your fatigue / energy-related illness after engaging in mental effort?

If you feel worse after activities, how long does this last?

If you do not exercise, is it because exercise makes your symptoms worse?

Understanding your DSQ-PEM result

What the score measures

The DSQ-PEM is a 10-question short form of the DePaul Symptom Questionnaire for post-exertional malaise (PEM), published by Cotler, Holtzman, Dudun and Jason in 2018. Five questions rate how often and how badly you have had PEM symptoms over the past six months. Five more ask how long the worsening lasts and what sets it off. It is free to use.

NICE describes PEM as a worsening of symptoms after activity that is often delayed by hours or days, out of proportion to the activity, and slow to recover from (NICE NG206; see the PEM explainer). Cotler and colleagues tested the five extra questions as a second step after the symptom questions (Cotler et al. 2018).

Score bands

Scoring has two steps. Step 1: PEM is indicated if any of the five symptoms happens at least half the time and is at least moderate, a frequency and severity of 2 or more out of 4. Step 2, the pattern that points to ME/CFS: you feel worse after minimal physical effort or after mental effort, and the worsening lasts 14 hours or more. The other two questions describe your PEM for a clinician but do not count towards either step.

How long worsening after activity lasted, by illness (% of each group, Cotler et al. 2018)
DurationME/CFSMultiple sclerosisPost-polio
Not worse after activity2.121.012.3
1 hour or less0.810.813.2
2–3 hours2.128.719.8
4–10 hours6.117.211.4
11–13 hours1.33.23.6
14–23 hours14.110.211.4
24 hours or more73.48.913.8

In the 2018 study, how long the worsening lasted was the question that best separated people with ME/CFS from people with multiple sclerosis or post-polio syndrome. A cut-off of 14 hours or more included 87.5% of the ME/CFS group and excluded 77.8% of the other two groups. 73.4% of people with ME/CFS said it lasted 24 hours or more, against 8.9% with multiple sclerosis and 13.8% with post-polio syndrome.

Step 1 alone is broad: 99% of the ME/CFS group met it. Only 1.3% of them said they would recover within an hour or two of an exhausting outing, against 42.3% with multiple sclerosis and 38.3% with post-polio syndrome.

What a change in score means

No minimal important change has been published. The symptom questions cover the past six months, so results a month apart overlap heavily. A change in whether PEM is indicated, or in how long the worsening lasts, says more than a small shift on a single symptom.

What it does not measure

No. It means the pattern you reported is consistent with PEM. The 2018 study compared ME/CFS only with multiple sclerosis and post-polio syndrome, and relied on people reporting their own diagnosis. A diagnosis needs a clinician, who will also look for other causes.

It does not measure how much activity you can manage. The FUNCAP records what everyday activities cost you, and the DSQ-2 checks a full symptom profile against ME/CFS case definitions.

Taking this to your GP or consultant

Bring the date, whether PEM was indicated, which symptoms met the threshold, how long the worsening lasts, and your saved results over time. Describe it as a 10-question DePaul questionnaire on post-exertional malaise, whose five symptom questions a US NIH/CDC working group recommended. PEM is one of the four symptoms NICE needs before ME/CFS is suspected, and NICE advises against programmes with fixed incremental increases in exercise, such as graded exercise therapy (recommendation 1.11.14). A positive result is a reason to discuss pacing; it cannot confirm ME/CFS. See preparing for a GP appointment.

Sources