title: Cross-cultural validation of the Chalder Fatigue Questionnaire in Brazilian primary care.
abstract: OBJECTIVE
  The Chalder Fatigue Questionnaire (CFQ) is an instrument used to measure physical and mental fatigue. We translated and adapted the questionnaire and tested its reliability and validity in a Brazilian primary care setting.
  
  
  METHODS
  A pilot study with 204 consecutive primary care attenders in Sao Paulo, Brazil, verified the internal consistency and factor structure of the questionnaire. After some modifications through a rigorous translation, back-translation, and cross-cultural adaptation procedure, a validation study was conducted with 304 attenders, who also completed the fatigue section of the Revised Clinical Interview Schedule (CIS-R).
  
  
  RESULTS
  The internal consistency of the Brazilian CFQ slightly improved from the pilot to the validation study: Cronbach's alpha from .86 to .88. The two-factor structure (physical and mental fatigue) also improved. According to the receiver operating curve analysis with the fatigue section of the CIS-R as the standard criterion, 3/4 was chosen as the cutoff for Brazilian primary care (sensitivity 69.1% and specificity 79.4%).
  
  
  CONCLUSIONS
  The Brazilian CFQ had good reliability and validity. The cutoff was determined as 3/4 and the factor structure of the English CFQ was closely reproduced.
authors.affiliation: Institute of Psychiatry, King's College London, London, United Kingdom. h.cho@iop.kcl.ac.uk
authors.forename: Hyong Jin
authors.initials: HJ
authors.lastname: Cho
authors.forename: Erico
authors.initials: E
authors.lastname: Costa
authors.forename: Paulo Rossi
authors.initials: PR
authors.lastname: Menezes
authors.forename: Trudie
authors.initials: T
authors.lastname: Chalder
authors.forename: Dinesh
authors.initials: D
authors.lastname: Bhugra
authors.forename: Simon
authors.initials: S
authors.lastname: Wessely
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil; D003431:Cross-Cultural Comparison; D005221:Fatigue / Q000175:diagnosis* / Q000523:psychology; D005260:Female; D006801:Humans; D007802:Language; D008297:Male; D005222:Mental Fatigue / Q000175:diagnosis* / Q000523:psychology; D008875:Middle Aged; D010555:Personality Inventory / Q000706:statistics & numerical data; D010865:Pilot Projects; D011320:Primary Health Care; D011594:Psychometrics / Q000706:statistics & numerical data; D012372:ROC Curve; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires