Test–retest reliability of the DePaul Symptom Questionnaire

Background: The DePaul Symptom Questionnaire (DSQ) was developed to provide a structured approach for collecting standardized symptomatology and health history information to allow researchers and clinicians to determine whether a patient meets the diagnostic criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), myalgic encephalomyelitis (ME), and/or chronic fatigue syndrome (CFS). Purpose: The purpose of this study was to examine the test–retest reliability of the DSQ. Methods: Test–retest reliability of the measure was examined with a sample of 26 adults self-identifying as having either ME/CFS, ME, and/or CFS and 25 adults who did not self-identify as having these illnesses and were otherwise healthy controls. Results: Overall, the majority of items on the DSQ exhibited good to excellent test–retest reliability, with Pearson's or kappa correlation coefficients that were 0.70 or higher. Conclusions: Thus, the present study suggests that the DSQ is a reliable diagnostic measure that can provide a standardized way of examining illness constructs and symptomatology among patients who identify as having ME/CFS, ME, and/or CFS.