title: Characterization of fatigue states in medicine and psychiatry by structured interview.
abstract: BACKGROUND
  Unexplained fatigue states are prevalent, with uncertain diagnostic boundaries.
  
  
  OBJECTIVE
  Patients with fatigue-related illnesses were investigated by questionnaire and a novel semistructured interview to identify discriminatory features.
  
  
  METHODS
  Cross-sectional samples of women from specialist practices with chronic fatigue syndrome (n = 20), postcancer fatigue (PCF; n = 20), or major depression (n = 16) were recruited. Additionally, two longitudinal samples were studied: women with fatigue associated with acute infection who subsequently developed postinfective fatigue syndrome (n = 20) or recovered uneventfully (n = 21), and women undergoing adjuvant therapy for breast cancer experiencing treatment-related fatigue who subsequently developed PCF (n = 16) or recovered uneventfully (n = 16). Patients completed self-report questionnaires, and trained interviewers applied the Semi-structured Clinical Interview for Neurasthenia. The receiver operating characteristics curves of the interview were measured against clinician-designated diagnoses. Cluster analyses were performed to empirically partition participants by symptom characteristics.
  
  
  RESULTS
  The interview had good internal consistency (Cronbach alpha "fatigue" = .83), and diagnostic sensitivity and specificity for chronic fatigue syndrome (100% and 83%) and major depression (100% and 72%), with reasonable parameters for PCF (72% and 58%). Empirical clustering by "fatigue" or "neurocognitive difficulties" items allocated most patients to one group, whereas "mood disturbance" items correctly classified patients with depression only.
  
  
  CONCLUSIONS
  The Semi-structured Clinical Interview for Neurasthenia offers reliable diagnostic use in assessing fatigue-related conditions. The symptom domains of fatigue and neurocognitive difficulties are shared across medical and psychiatric boundaries, whereas symptoms of depression such as anhedonia are distinguishing.
authors: Barbara Kaye
authors: BK
authors: Bennett
authors: David
authors: D
authors: Goldstein
authors: Michelle
authors: M
authors: Chen
authors: Tracey A
authors: TA
authors: Davenport
authors: Ute
authors: U
authors: Vollmer-Conna
authors: Elizabeth M
authors: EM
authors: Scott
authors: Ian B
authors: IB
authors: Hickie
authors: Andrew R
authors: AR
authors: Lloyd
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000150:complications; D016000:Cluster Analysis; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000150:complications / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005221:Fatigue / Q000175:diagnosis* / Q000209:etiology / Q000523:psychology; D015673:Fatigue Syndrome, Chronic / Q000523:psychology; D005260:Female; D006801:Humans; D007239:Infections / Q000150:complications; D007406:Interview, Psychological; D008875:Middle Aged; D009440:Neurasthenia / Q000175:diagnosis* / Q000209:etiology; D010146:Pain / Q000150:complications; D011570:Psychiatry / Q000379:methods; D012372:ROC Curve; D057566:Self Report; D012680:Sensitivity and Specificity; D012959:Socioeconomic Factors