title: International FItness Scale (IFIS): Construct Validity and Reliability in Women With Fibromyalgia: The al-Ándalus Project.
abstract: OBJECTIVE
  To examine the construct validity of the International FItness Scale (IFIS) (ie, self-reported fitness) against objectively measured physical fitness in women with fibromyalgia and in healthy women; and to study the test-retest reliability of the IFIS in women with fibromyalgia.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Fibromyalgia patient support groups.
  
  
  METHODS
  Women with fibromyalgia (n=413) and healthy women (controls) (n=195) for validity purposes and women with fibromyalgia (n=101) for the reliability study. The total sample was N=709.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Fitness level was both self-reported (IFIS) and measured using performance-based fitness tests. For the reliability study the IFIS was completed on 2 occasions, 1 week apart.
  
  
  RESULTS
  Women with fibromyalgia who reported average fitness had better measured fitness than those reporting very poor fitness (all P<.001, except 6-minute walk test where P<.05), with similar trends observed in healthy control women. The test-retest reliability of the IFIS, as measured by the average weighted κ, was .45.
  
  
  CONCLUSIONS
  The IFIS was able to identify women with fibromyalgia who had very low fitness and distinguish them from those with higher fitness levels. Furthermore, the IFIS was moderately reliable in women with fibromyalgia.
authors: Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain. Electronic address: alvarezg@ugr.es.
authors: Inmaculada C
authors: IC
authors: Álvarez-Gallardo
authors: Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain.
authors: Alberto
authors: A
authors: Soriano-Maldonado
authors: Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain.
authors: Víctor
authors: V
authors: Segura-Jiménez
authors: Department of Physical Education, Faculty of Education Science, University of Cadiz, Cadiz, Spain.
authors: Ana
authors: A
authors: Carbonell-Baeza
authors: Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain; Department of Clinical and Health Psychology, Faculty of Social and Behavioral Sciences, Utrecht University, Utrecht, The Netherlands.
authors: Fernando
authors: F
authors: Estévez-López
authors: Institute of Nursing and Health Research, School of Health Sciences, Ulster University, Northern Ireland, United Kingdom.
authors: Joseph G
authors: JG
authors: McVeigh
authors: Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain.
authors: Manuel
authors: M
authors: Delgado-Fernández
authors: PROFITH "PROmoting FITness and Health through physical activity" Research Group, Faculty of Sport Sciences, Department of Physical Education and Sports, University of Granada, Granada, Spain.
authors: Francisco B
authors: FB
authors: Ortega
mesh_terms: D003430:Cross-Sectional Studies; D005260:Female; D005356:Fibromyalgia / Q000503:physiopathology*; D006801:Humans; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology; D010809:Physical Fitness; D015203:Reproducibility of Results; D012647:Self-Assessment; D012944:Social Support
keywords: Chronic pain; Fibromyalgia; Muscle strength; Physical fitness; Rehabilitation; Self-assessment