title: Systematic content evaluation and review of measurement properties of questionnaires for measuring self-reported fatigue among older people.
abstract: OBJECTIVE
  The assessment of fatigue in older people requires simple and user-friendly questionnaires that capture the phenomenon, yet are free from items indistinguishable from other disorders and experiences. This study aimed to evaluate the content, and systematically review and rate the measurement properties of self-report questionnaires for measuring fatigue, in order to identify the most suitable questionnaires for older people.
  
  
  METHODS
  This study firstly involved identification of questionnaires that purport to measure self-reported fatigue, and evaluation of the content using a rating scale developed for the purpose from contemporary understanding of the construct. Secondly, for the questionnaires that had acceptable content, we identified studies reporting measurement properties and rated the methodological quality of those studies according to the COSMIN system. Finally, we extracted and synthesised the results of the studies to give an overall rating for each questionnaire for each measurement property. The protocol was registered with PROSPERO (CRD42013005589).
  
  
  RESULTS
  Of the 77 identified questionnaires, twelve were selected for review after content evaluation. Methodological quality varied, and there was a lack of information on measurement error and responsiveness.
  
  
  CONCLUSIONS
  The PROMIS-Fatigue item bank and short forms perform the best. The FACIT-Fatigue scale, Parkinsons Fatigue Scale, Perform Questionnaire, and Uni-dimensional Fatigue Impact Scale also perform well and can be recommended. Minor modifications to improve performance are suggested. Further evaluation of unresolved measurement properties, particularly with samples including older people, is needed for all the recommended questionnaires.
authors.affiliation: Department of Neuroscience, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway, thor@sutmap.com.
authors.forename: Thorlene
authors.initials: T
authors.lastname: Egerton
authors.forename: Ingrid I
authors.initials: II
authors.lastname: Riphagen
authors.forename: Arnhild J
authors.initials: AJ
authors.lastname: Nygård
authors.forename: Pernille
authors.initials: P
authors.lastname: Thingstad
authors.forename: Jorunn L
authors.initials: JL
authors.lastname: Helbostad
mesh_terms: D000368:Aged; D016208:Databases, Factual; D005221:Fatigue / Q000175:diagnosis* / Q000523:psychology; D006801:Humans; D011788:Quality of Life; D057566:Self Report; D011795:Surveys and Questionnaires