title: International Psychometric Validation of an EORTC Quality of Life Module Measuring Cancer Related Fatigue (EORTC QLQ-FA12).
abstract: The European Organisation for Research and Treatment of Cancer (EORTC) Group has developed a new multidimensional instrument measuring cancer-related fatigue to be used in conjunction with the quality of life core questionnaire (EORTC QLQ-C30). The module EORTC QLQ-FA13 assesses physical, cognitive, and emotional aspects of cancer-related fatigue.
  
  
  
  The methodology follows the EORTC guidelines for phase IV validation of modules. This paper focuses on the results of the psychometric validation of the factorial structure of the module. For validation and cross-validation confirmatory factor analysis (maximum likelihood estimation), intraclass correlation and Cronbach alpha for internal consistency were employed. The study involved an international multicenter collaboration of 11 European and non-European countries.
  
  
  
  A total of 946 patients with various tumor diagnoses were enrolled. Based on the confirmatory factor analysis, we could approve the three-dimensional structure of the module. Removing one item and reassigning the factorial mapping of another item resulted in the EORTC QLQ-FA12. For the revised scale, we found evidence supporting good local (indicator reliability ≥ 0.60, factor reliability ≥ 0.82) and global model fit (GFI t1|t2 = 0.965/0.957, CFI t1|t2 = 0.976/0.972, RMSEA t1|t2 = 0.060/0.069) for both measurement points. For each scale, test-retest reliability proved to be very good (intraclass correlation: R t1-t2 = 0.905-0.921) and internal consistency proved to be good to high (Cronbach alpha = .79-.90).
  
  
  
  Based on the former phase III module, the multidimensional structure was revised as a phase IV module (EORTC FA12) with an improved scale structure. For a comprehensive validation of the EORTC FA12, further aspects of convergent and divergent validity as well as sensitivity to change should be determined.
authors.affiliation: Tumor Biology Centre, University Clinic Centre, Freiburg, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Weis
authors.affiliation: Faculty of Medicine, Jagiellonian University Medical College, Krakow, Poland.
authors.forename: Krzysztof A
authors.initials: KA
authors.lastname: Tomaszewski
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: Eva
authors.initials: E
authors.lastname: Hammerlid
authors.affiliation: Oncology Departments, Complejo Hospitalario de Navarra, Pamplona, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Ignacio Arraras
authors.affiliation: Department of Medical Oncology, Lorraine Cancer Institute, Nancy, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Conroy
authors.affiliation: Institute for Women's Health, University College, London, UK.
authors.forename: Anne
authors.initials: A
authors.lastname: Lanceley
authors.affiliation: Institute of Health and Nursing Science, Medical Faculty, Martin Luther University, Halle, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Schmidt
authors.affiliation: Department of Research Methods, University of Education, Freiburg, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Wirtz
authors.affiliation: Division of Epidemiology and Health Services Research, Institute of Medical Biostatistics, Epidemiology and Informatics, University Medical Centre, Mainz, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Singer
authors.affiliation: Rehabilitation Unit, Department of Health Policy, Farmacy and Quality of Life, Istituto Nazionale, Tumori "Fondazione Giovanni Pascale," IRCCS, Naples, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Pinto
authors.affiliation: Department of Clinical Oncology, Tanta Faculty of Medicine, Egypt.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Alm El-Din
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW (School for Oncology and Developmental Biology), University of Maastricht Medical Center, Maastricht, The Netherlands.
authors.forename: Inge
authors.initials: I
authors.lastname: Compter
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Holzner
authors.affiliation: Department of Medical Psychology and Medical Sociology, University of Leipzig, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Hofmeister
authors.affiliation: Department of Family Medicine, National Taiwan University, Taiwan.
authors.forename: Wei-Chu
authors.initials: WC
authors.lastname: Chie
authors.affiliation: Research and Development Office, Southern Health NHS Foundation Trust, Southampton, UK.
authors.forename: Marek
authors.initials: M
authors.lastname: Czeladzki
authors.affiliation: Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.
authors.forename: Amelie
authors.initials: A
authors.lastname: Harle
authors.affiliation: HPB Services Directorate of Surgery, University Hospital Aintree, Liverpool, UK.
authors.forename: Louise
authors.initials: L
authors.lastname: Jones
authors.affiliation: Institute of Research in Rehabilitation Medicine at Ulm University, Ulm, Germany.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Ritter
authors.affiliation: Department of Paediatric Psychiatry, University of Magdeburg, Magdeburg, Germany.
authors.forename: Hans-Henning
authors.initials: HH
authors.lastname: Flechtner
authors.affiliation: Quality of Life Department, EORTC Headquarters, Brussels, Belgium.
authors.forename: Andrew
authors.initials: A
authors.lastname: Bottomley
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004534:Egypt; D004644:Emotions; D005060:Europe; D005163:Factor Analysis, Statistical; D005221:Fatigue / Q000209:etiology* / Q000523:psychology; D005260:Female; D006801:Humans; D038622:Internationality; D008297:Male; D005222:Mental Fatigue / Q000209:etiology / Q000523:psychology; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications* / Q000628:therapy; D010166:Palliative Care; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D017741:Survivors / Q000523:psychology; D013624:Taiwan; D055815:Young Adult