Test-retest reliability of the Food Allergy Quality of Life Questionnaires (FAQLQ) for children, adolescents and adults.
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.
van der Velde
Jantina L
JL
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.
Flokstra-de Blok
Bertine M J
BM
Vlieg-Boerstra
Berber J
BJ
Oude Elberink
Joanne N G
JN
Schouten
Jan P
JP
Dunngalvin
Audrey
A
Hourihane
Jonathan O'B
JO
Duiverman
Eric J
EJ
Dubois
Anthony E J
AE
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*