title: Fatigue in Brazilian cancer patients, caregivers, and nursing students: a psychometric validation study of the Piper Fatigue Scale-Revised.
abstract: OBJECTIVE
  The objective of this study was to validate the Piper Fatigue Scale-Revised (PFS-R) for use in Brazilian culture.
  
  
  METHODS
  Translation of the PFS-R into Portuguese and validity and reliability tests were performed. Convenience samples in Brazil we as follows: 584 cancer patients (mean age 57 +/- 13 years; 51.3% female); 184 caregivers (mean age 50 +/- 12.7 years; 65.8% female); and 189 undergraduate nursing students (mean age 21.6 +/- 2.8 years; 96.2% female); Instruments used were as follows: Brazilian PFS, Beck Depression Inventory (BDI), and Karnofsky Performance Scale (KPS).
  
  
  RESULTS
  The 22 items of the Brazilian PFS loaded well (factor loading > 0.35) on three dimensions identified by factor analysis (behavioral, affective, and sensorial-psychological). These dimensions explained 65% of the variance. Internal consistency reliability was very good (Cronbach's alpha ranged from 0.841 to 0.943 for the total scale and its dimensions). Cancer patients and their caregivers completed the Brazilian PFS twice for test-retest reliability and results showed good stability (Pearson's r > or = 0.60, p < 0.001). Correlations among the Brazilian PFS and other scales were significant, in hypothesized directions, and mostly moderate contributing to divergent (Brazilian PFS x KPS) and convergent validity (Brazilian PFS x BDI). Mild, moderate, and severe fatigue in patients were reported by 73 (12.5%), 167 (28.6%), and 83 (14.2%), respectively. Surprisingly, students had the highest mean total fatigue scores; no significant differences were observed between patients and caregivers showing poor discriminant validity.
  
  
  CONCLUSIONS
  While the Brazilian PFS is a reliable and valid instrument to measure fatigue in Brazilian cancer patients, further work is needed to evaluate the discriminant validity of the scale in Brazil.
authors.affiliation: Sao Paulo Cancer Institute (Brazil), Av. Dr. Arnaldo, 251, 5 degrees andar, São Paulo, São Paulo 01246-000, Brazil. dalete.mota@globo.com
authors.forename: Dálete D C F
authors.initials: DD
authors.lastname: Mota
authors.forename: Cibele A M
authors.initials: CA
authors.lastname: Pimenta
authors.forename: Barbara F
authors.initials: BF
authors.lastname: Piper
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil / Q000453:epidemiology; D017028:Caregivers / Q000523:psychology*; D005221:Fatigue / Q000175:diagnosis* / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications*; D011594:Psychometrics; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013338:Students, Nursing / Q000523:psychology*; D055815:Young Adult