E3 PreliminaryModerate confidencePEM ?Methods-PaperPeer-reviewedMachine draft
Test-Retest Reliability of the DePaul Symptom Questionnaire.
Jason, Leonard A, So, Suzanna, Brown, Abigail A et al. · Fatigue : biomedicine, health & behavior · 2015 · DOI
Quick Summary
Researchers tested whether the DePaul Symptom Questionnaire (DSQ)—a tool designed to help doctors diagnose ME/CFS—gives consistent results when used multiple times. They asked 26 people with ME/CFS and 25 healthy people to answer the same questions at different times. The questionnaire proved reliable, meaning patients' answers were consistent, making it a trustworthy tool for identifying who has ME/CFS.
Why It Matters
A reliable diagnostic tool is essential for ME/CFS, where diagnosis is often delayed or missed due to lack of standardized assessment methods. The DSQ's reliability suggests it can help clinicians and researchers consistently identify patients who meet diagnostic criteria, potentially improving access to appropriate care and enabling more rigorous research enrollment.
Observed Findings
- Majority of DSQ items showed good to excellent test-retest reliability with correlation coefficients of 0.70 or higher
- Both ME/CFS patients and healthy controls were included in the reliability assessment
- The questionnaire captured standardized symptomatology and health history information across both groups
- 51 total participants completed the study (26 patients, 25 controls)
Inferred Conclusions
- The DSQ is a reliable diagnostic measure suitable for standardized assessment of ME/CFS symptoms
- The DSQ can provide a consistent way to examine illness constructs across diverse populations
- The tool's reliability supports its use in both clinical and research settings for ME/CFS diagnosis
Remaining Questions
- Does DSQ reliability hold in larger and more diverse patient populations?
- Is the DSQ valid at distinguishing ME/CFS from other conditions with similar symptoms (e.g., fibromyalgia, long COVID)?
- How does the DSQ perform in patients diagnosed by clinical criteria versus self-identification?
- Are there specific DSQ items with lower reliability that need revision or clarification?
What This Study Does Not Prove
This study demonstrates consistency of the DSQ but does not prove it is valid for diagnosing ME/CFS—reliability (consistency) and validity (accuracy) are different properties. The study does not establish whether the DSQ correctly distinguishes ME/CFS from other conditions, nor does it determine whether patient self-identification matches clinical diagnostic criteria.
Tags
Symptom:Post-Exertional MalaiseCognitive DysfunctionUnrefreshing SleepOrthostatic IntolerancePainFatigueSensory SensitivityTemperature Dysregulation
Method Flag:Small SampleExploratory Only