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Your patients need you to understand ME/CFS. The evidence is here — structured and sourced.
Guidance
- Use the IOM (2015) diagnostic criteria: substantial reduction in activity, PEM, unrefreshing sleep, plus cognitive impairment or orthostatic intolerance.
- Ask about PEM specifically and in detail: "Does physical or mental activity cause a delayed worsening of symptoms? How long does it last?" Many patients won't volunteer this unless asked.
- ME/CFS is a diagnosis of inclusion — the criteria are specific. It is not a diagnosis of exclusion, though common differentials should be ruled out: thyroid, anaemia, diabetes, sleep disorders, coeliac.
- Severity ranges from mild (reduced activity, still working part-time) to very severe (bedbound, unable to tolerate light or sound). Assess functional capacity, not just symptoms.
If you read one thing
Standard · 3 min
Diagnostic criteria (IOM report)
The IOM diagnostic criteria — what to look for and how to assess ME/CFS.
Read this →Recommended reads
Evidence Atlas
Deep dive · 10+ min
Structured, rated studies across biological, neurological, and clinical domains.
Understanding Post-Exertional Malaise
Standard · 3 min
PEM is the hallmark feature — why it matters clinically and how to assess it.
About ME/CFS Atlas
Quick read · 30 sec
How this atlas rates evidence, flags PEM relevance, and handles uncertainty.
More resources are available in the Atlas and Evidence sections.