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A Brief Questionnaire to Assess Post-Exertional Malaise.

Cotler, Joseph, Holtzman, Carly, Dudun, Catherine et al. · Diagnostics (Basel, Switzerland) · 2018 · DOI

Quick Summary

This study focused on creating a better way to identify post-exertional malaise (PEM)—the worsening of symptoms that happens after physical or mental activity in ME/CFS patients. Researchers tested whether five additional questions from an existing questionnaire could help doctors confirm PEM in the second step of diagnosis. The test was successful: it correctly identified patients with ME/CFS 82% of the time and rarely misidentified other conditions like multiple sclerosis as ME/CFS.

Why It Matters

Standardizing how doctors diagnose post-exertional malaise is critical for ME/CFS patients because PEM is a defining feature of these conditions. Without clear diagnostic tools, patients may be misdiagnosed or have their condition dismissed. This research provides healthcare providers with a practical, evidence-based method to reliably identify PEM and confirm ME/CFS diagnoses.

Observed Findings

  • The five supplementary DSQ PEM duration items correctly categorized patients with ME or CFS 81.7% of the time.
  • The same items incorrectly categorized multiple sclerosis patients as having ME or CFS only 16.6% of the time.
  • The same items incorrectly categorized post-polio syndrome patients as having ME or CFS only 16.6% of the time.
  • The supplementary items demonstrated high specificity in distinguishing ME/CFS from other neurological conditions.

Inferred Conclusions

  • A standardized second-step process for PEM assessment can be operationalized using supplementary DSQ items.
  • These supplementary items are useful for confirming the presence of PEM following initial screening questions.
  • The DSQ items effectively differentiate ME/CFS from other chronic neurological conditions with similar symptoms.

Remaining Questions

  • How do these supplementary items perform across diverse demographic groups (age, sex, ethnicity, socioeconomic status)?
  • What is the reliability and validity of this tool when administered by different types of healthcare providers in varied clinical settings?
  • Can this two-step PEM assessment process be improved by incorporating objective biomarkers or additional clinical measures?
  • How sensitive and specific is this questionnaire for distinguishing ME/CFS from other conditions that may present with post-exertional symptom worsening (e.g., POTS, long COVID)?

What This Study Does Not Prove

This study does not prove that these five questions are sufficient for definitive ME/CFS diagnosis on their own—they represent only the second step in a multi-step process. The study also does not establish whether this questionnaire works equally well across all demographic groups or in all healthcare settings. Additionally, the relatively small sample sizes for some comparison groups limit generalizability.

Topics

Post-Exertional Malaise

Tags

Symptom:Post-Exertional Malaise
Method Flag:Exploratory Only

Metadata

DOI
10.3390/diagnostics8030066
PMID
30208578
Review status
Machine draft
Evidence level
Single-study or moderate support from human research
Last updated
7 April 2026