title: Test-retest reliability of the Food Allergy Quality of Life Questionnaires (FAQLQ) for children, adolescents and adults.
abstract: OBJECTIVE
  The self-administered Food Allergy Quality of Life Questionnaire-Child Form (FAQLQ-CF), -Teenager Form (FAQLQ-TF) and -Adult Form (FAQLQ-AF) were recently developed within EuroPrevall, a multi-centred study of food allergy in Europe. The primary aim of this study was to evaluate the test-retest reliability of the FAQLQ-CF, -TF and -AF.
  
  
  METHODS
  One hundred and one Dutch patients (31 children, 34 adolescents and 36 adults) completed the FAQLQ twice with a 10-14 day interval. The intraclass correlation coefficient (ICC), Lin's concordance correlation coefficient (CCC) and Bland-Altman plots were used to assess test-retest reliability.
  
  
  RESULTS
  Test-retest reliability was excellent with ICCs and CCCs above 0.907, 0.975 and 0.951 for the FAQLQ-CF, -TF and -AF, respectively. Bland-Altman plots showed that the mean differences of the test and re-test were all close to zero for the FAQLQs.
  
  
  CONCLUSIONS
  The FAQLQs are reliable over a short time interval. The FAQLQs are not only excellent tools for group comparison studies, but also for monitoring individual patients.
authors.affiliation: Department of Pediatrics, Division of Pediatric Pulmonology and Pediatric Allergy, University Medical Center Groningen, University of Groningen, Groningen, P.O. Box 30.001, 9700 RB, The Netherlands.
authors.forename: Jantina L
authors.initials: JL
authors.lastname: van der Velde
authors.forename: Bertine M J
authors.initials: BM
authors.lastname: Flokstra-de Blok
authors.forename: Berber J
authors.initials: BJ
authors.lastname: Vlieg-Boerstra
authors.forename: Joanne N G
authors.initials: JN
authors.lastname: Oude Elberink
authors.forename: Jan P
authors.initials: JP
authors.lastname: Schouten
authors.forename: Audrey
authors.initials: A
authors.lastname: Dunngalvin
authors.forename: Jonathan O'B
authors.initials: JO
authors.lastname: Hourihane
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Duiverman
authors.forename: Anthony E J
authors.initials: AE
authors.lastname: Dubois
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D005260:Female; D005512:Food Hypersensitivity / Q000523:psychology*; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires / Q000592:standards*