The utility of patient-reported outcome measures among patients with myalgic encephalomyelitis/chronic fatigue syndrome.
Debilitating fatigue is a core symptom of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS); however, the utility of patient-reported symptom outcome measures of fatigue for ME/CFS patients is problematic due to ceiling effects and issues with reliability and validity. We sought to evaluate the performance of three patient-reported symptom measures in a sample of ME/CFS patients and matched controls.



Two hundred and forty ME/CFS patients and 88 age, sex, race, and zip code matched controls participated in the study. Participants completed the Multidimensional Fatigue Inventory-20, DePaul Symptom Questionnaire, and RAND SF-36.



The general and physical fatigue subscales on Multidimensional Fatigue Inventory-20, as well as the role of physical health on the RAND SF-36, demonstrated questionable or unacceptable internal consistency and problematic ceiling effects. The DePaul Symptom Questionnaire demonstrated excellent internal reliability, and less than 5 % of participants were at the ceiling on each subscale. The post-exertional malaise subscale on the DePaul Symptom Questionnaire demonstrated excellent clinical utility as it was able to differentiate between ME/CFS patients and controls (OR 1.23, p < .001) and predicted ceiling effects on other patient-reported outcome subscales. A score of 20 on the post-exertional malaise subscale of the DePaul Symptom Questionnaire optimally differentiated between patients and controls.



Significant ceiling effects and concerns with reliability and validity were observed among Multidimensional Fatigue Inventory-20 and RAND SF-36 subscales for ME/CFS patients. The DePaul Symptom Questionnaire addresses a number of concerns typically identified when using patient-reported outcome measures with ME/CFS patients; however, an improved multidimensional patient-reported outcome tool for measuring ME/CFS-related symptoms is warranted.
Department of Psychology, Rice University, Houston, TX, USA.
Kyle W
KW
Murdock
Department of Symptom Research, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Unit 1450, Houston, TX, 77030, USA. xswang@mdanderson.org.
Xin Shelley
XS
Wang
Department of Symptom Research, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Unit 1450, Houston, TX, 77030, USA.
Qiuling
Q
Shi
Department of Symptom Research, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Unit 1450, Houston, TX, 77030, USA.
Charles S
CS
Cleeland
Department of Psychology, Rice University, Houston, TX, USA.|Department of Symptom Research, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Unit 1450, Houston, TX, 77030, USA.
Christopher P
CP
Fagundes
Bateman Horne Center of Excellence, Salt Lake City, UT, USA.
Suzanne D
SD
Vernon
D000293:Adolescent; D000328:Adult; D000368:Aged; D003627:Data Interpretation, Statistical; D015673:Fatigue Syndrome, Chronic / Q000523:psychology* / Q000534:rehabilitation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000071066:Patient Reported Outcome Measures; D015203:Reproducibility of Results; D057566:Self Report; D055815:Young Adult
Chronic fatigue syndrome; Fatigue; Myalgic encephalomyelitis; Sensitivity; Symptom measurement