Comparison of a generic and a rhinitis-specific quality-of-life (QOL) instrument in patients with house dust mite allergy: relationship between the SF-36 and Rhinitis QOL Questionnaire.
BACKGROUND
Generic and disease-specific quality-of-life (QOL) questionnaires are commonly used in subjects with allergic rhinitis (AR). AR, however, is closely associated with other disorders such as bronchial asthma and atopic dermatitis (AD). These co-morbid associations may have an effect on the inter-relation of generic and disease-specific QOL outcomes and the behaviour of this inter-relation in time.


OBJECTIVE
To unravel the inter-relationships between the outcome of a generic instrument (SF-36) and a disease-specific instrument (Rhinitis QOL Questionnaire (RQLQ)).


METHODS
In the framework of a randomized clinical trial with respect to the efficacy of impermeable bedding covers in house dust mite (HDM) allergy, SF-36 and RQLQ were administered to 224 adults with AR and/or allergic asthma and/or AD at baseline and after 12 months of intervention. Regression analysis and canonical correlation were used to estimate overlap.


RESULTS
Overlap between SF-36 and RQLQ domains in terms of explained variance ranged from 6% to 56%. Canonical correlation yielded low coefficients (0.16-0.27). Moreover, both SF-36 and RQLQ scores did not change significantly during the intervention.


CONCLUSIONS
In patients with HDM allergy characterized by co-morbid associations, SF-36 and RQLQ cover different aspects in QOL. It is advocated to use both simultaneously in performing QOL studies.
Terreehorst
I
I
Department of Allergology, Erasmus Medical Centre, Rotterdam, The Netherlands. i.terreehorst@erasmusmc.nl
Duivenvoorden
H J
HJ
Tempels-Pavlica
Z
Z
Oosting
A J
AJ
de Monchy
J G R
JG
Bruijnzeel-Koomen
C A F M
CA
Gerth van Wijk
R
R
D000293:Adolescent; D000328:Adult; D002648:Child; D040002:Dermatophagoides pteronyssinus / Q000276:immunology; D004311:Double-Blind Method; D004391:Dust / Q000276:immunology; D006305:Health Status Indicators; D006801:Humans; D008875:Middle Aged; D011788:Quality of Life; D015203:Reproducibility of Results; D012221:Rhinitis, Allergic, Perennial / Q000209:etiology / Q000534:rehabilitation*; D011795:Surveys and Questionnaires
D004391:Dust