Tools

ME/CFS screening questionnaire

The DSQ-Brief: a 4-item self-check

This is a free, interactive version of the DSQ-Brief, a short screening scale for myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) developed by Leonard Jason and colleagues at DePaul University and published in 2023. It was drawn from the much longer DePaul Symptom Questionnaire: the authors picked the four symptom questions that identify people who meet the Institute of Medicine (IOM) case definition for ME/CFS.

Those four items cover fatigue, tiredness after minimal exercise (a sign of post-exertional malaise), unrefreshing sleep and memory problems. In the validation study of 3,427 people, the four questions told people with ME/CFS apart from healthy controls with 96% accuracy (94% sensitivity, 98% specificity).

It is intended for anyone with persistent fatigue, a post-viral illness, or suspected ME/CFS who wants a quick, structured self-check before deciding whether to look into things further. It takes under two minutes. Answer each item for how it has been over the past six months, and you will get an immediate result with a per-symptom breakdown. No sign-up or email is required, and nothing you enter leaves your device. To characterise your post-activity symptom pattern in more depth, the DSQ-PEM adds recovery time and triggers; for the complete assessment, take the full DSQ-2.

This is not a diagnostic tool. A screening result reflects self-reported symptoms and is not a diagnosis of ME/CFS or any other condition. The DSQ-Brief is very good at telling ME/CFS apart from health, but less so from other fatiguing illnesses, so a result here is a starting point for a conversation with your doctor, not a conclusion. Based on: Jason LA, Benner S, Furst J, Cathey P. Developing and validating a brief screening scale for ME/CFS. Fatigue: Biomedicine, Health & Behavior. 2023;11(2–4):176–87.

For each symptom, rate how often you have had it and how severe it has been, over the past six months.

1Fatigue/extreme tiredness

How often
How severe

2Minimum exercise makes you physically tired

How often
How severe

3Feeling unrefreshed after you wake up in the morning

How often
How severe

4Problems remembering things

How often
How severe

Understanding your DSQ-Brief result

What the score measures

The DSQ-Brief is a 4-question screen for ME/CFS from DePaul University, published by Jason, Benner, Furst and Cathey in 2023. It asks how often and how severely you have had fatigue, physical tiredness after minimal exercise, unrefreshing sleep and problems remembering things over the past six months. The four questions were chosen to pick out people who meet the Institute of Medicine (IOM) case definition for ME/CFS.

The wording follows DePaul's published form (DSQ-Brief form (DePaul)). Each symptom's 0 to 100 score combines frequency and severity, as DePaul does in its research; it is for tracking and has no cut-off.

Score bands

Each symptom is rated for frequency and severity from 0 to 4. As in DePaul's other questionnaires, a symptom counts when both are 2 or more: at least half the time and at least moderate. The paper tested the four questions with a statistical model rather than a simple cut-off, so the rule for a positive screen here is this site's own: all four symptoms must count.

The 2/2 rule is the one DePaul uses elsewhere (Cotler et al. 2018), and the four symptoms line up with the four NICE needs before ME/CFS is suspected: fatigue worsened by activity, post-exertional malaise, unrefreshing sleep and cognitive difficulties (NICE NG206).

In the validation study of 3,427 people, the DSQ-Brief told people with ME/CFS apart from healthy controls with 96% accuracy (94% sensitivity, 98% specificity). Against a group with long COVID, multiple sclerosis or post-polio syndrome, accuracy fell to 84% (85% sensitivity, 81% specificity). The authors suggest following it with a longer DePaul questionnaire.

Accuracy / sensitivity / specificity (%) in the validation study, as summarised by ME Research UK
QuestionnaireME/CFS vs healthy controlsME/CFS vs other illnesses
DSQ-Brief (4 items)96 / 94 / 9884 / 85 / 81
DSQ-SF (14 items)98 / 97 / 9993 / 93 / 94
DSQ-1 (54 items)99 / 98 / 9994 / 95 / 94

These figures come from a statistical model, not from this page's 4-of-4 rule, so they describe the four questions rather than this page's verdict.

What a change in score means

No minimal important change has been published. The questions cover the past six months, so repeat it every few months rather than weekly, and watch whether the number of symptoms at the threshold changes rather than small shifts in the 0 to 100 item scores.

What it does not measure

No. A positive screen means your answers match the four symptoms the screen looks for. It is less accurate at telling ME/CFS apart from other illnesses that cause fatigue, and a diagnosis needs a clinician to assess you and rule out other causes. A negative screen does not rule ME/CFS out either.

It does not cover orthostatic intolerance, pain or how long you have been ill. The DSQ-PEM looks at post-exertional malaise in depth, and the DSQ-2 checks four ME/CFS case definitions.

Taking this to your GP or consultant

Bring the date, the verdict, which symptoms met the threshold, and any earlier results. Describe it as a 4-question screen from the DePaul Symptom Questionnaire, published in 2023. NICE says ME/CFS should be suspected when all four core symptoms have lasted 6 weeks in an adult whose activity has dropped markedly, and diagnosed only after 3 months and an assessment for other causes. A positive screen is a reason to ask for that assessment, not evidence of ME/CFS on its own. See preparing for a GP appointment.

Sources