Leonard A. Jason, Meredyth Evans, Molly Brown, Nicole Porter, Abigail Brown, Jessica Hunnell, Valerie Anderson, Athena Lerch
As indicated in this study, definitions of fatigue might need to include specific guidelines pertaining to the importance of symptom severity in the diagnostic procedure (Cantwell, 1996). Given the high variability in symptom severity among persons with fatigue, standardized procedures need to be employed for determining whether or not a particular symptom is severe enough to qualify as meeting the fatigue criterion for CFS.
There is a need for more basic research investigating the specificity and sensitivity of different fatigue criteria being used to diagnose CFS. Determining whether participants meet criteria for symptoms or for substantial reductions in activities also requires more standardization of procedures.
Future research is clearly needed to identify instruments that differentiate CFS from other chronic illnesses (Jason et al., 1997), and to assess the specificity and sensitivity of these measures.
MDD: major depressive disorder