Original article Screening for allergic respiratory disease in the general population with the ADVIA Centaur Ò Allergy Screen Assay Respiratory diseases represent a significant number of consultations. Efficient diagnostic measures are needed to evaluate these patients. A specific diagnosis of immuno- globulin E (IgE)-mediated allergic respiratory disease (1) may facilitate the initiation of a specific treatment (2). Based on the case history and clinical examination alone it is often difficult to distinguish between IgE-mediated and non-IgE-mediated allergic respiratory disease. When IgE-mediated allergic respiratory disease is suspected, measurement of skin prick test (SPT) reactivity or specific IgE in serum against relevant and available allergens are considered first-line diagnostic procedures (2). Con- versely, in patients in whom the clinical indication for IgE-mediated allergic respiratory disease is weak, a single qualitative multiallergen-screening assay for IgE antibody to multiple allergen specificities can support the absence of IgE-mediated allergic respiratory disease (3). Such a test provides a dichotomous (positive or negative) result. The negative predictive value (NPV) of this single test is generally higher than total IgE or any single specific IgE antibody measurement (4). Validated objective measures of allergic respiratory disease are furthermore needed for epidemiological stud- ies, which may increasingly be based on stored serum samples from biobanks. Measures used for this purpose should prove reasonably sensitive and specific in relation to a clinical diagnosis or gold standard. The aim of this study was to investigate the diagnostic efficacy of a new multiallergen-screening assay in relation to SPT reactivity and objective clinical diagnoses of allergic respiratory disease in a general population setting. Methods Study population Subjects included in these analyses participated in the first follow up of a prospective cohort study in adults: the Copenhagen Allergy Study (5). The baseline study was established in 1990 and was conducted according to a two-stage protocol (6). In the first stage, a screening questionnaire on respiratory symptoms was mailed to a Background: In patients in whom the clinical indication for immunoglobulin E (IgE)-mediated allergic respiratory disease is weak, a single qualitative multial- lergen-screening assay for IgE antibody to multiple allergen specificities may support the absence of IgE-mediated allergic respiratory disease. The aim was to investigate the diagnostic efficacy of a new multiallergen-screening assay in relation to skin prick test (SPT) reactivity and objective diagnoses of allergic respiratory disease in a general population setting. Methods: A total of 709 participants in a population-based study were examined by questionnaire and SPT. Serum was analysed by using a multiallergen- screening assay: the ADVIA Centaur Ò Allergy Screen (AS) assay. The dicho- tomized result of the AS assay was compared with SPT reactivity, specific IgE positivity, and a clinical diagnosis of allergic rhinitis or allergic asthma defined by the presence of relevant symptoms and positive SPTs. Results: Sensitivity, specificity, and positive (PPV) and negative predictive values (NPV) of the AS against SPT reactivity were 86%, 96%, 94%, and 89%, respectively. A negative AS assay test was able to exclude allergic rhinitis and allergic asthma with a probability of more than 96% and 98% (NPV), respectively. The AS assay was able to identify more than 92% and 92% (sensitivity) of cases of allergic rhinitis and allergic asthma, respectively. Conclusions: The AS assay proved to be a valid measure of allergic respiratory disease and may be used as a screening tool to rule out allergic respiratory disease, and as an objective measure of allergic respiratory disease in epidemi- ological studies. A. Linneberg 1 , L. L. N. Husemoen 1 , N. H. Nielsen 2 , F. Madsen 3 , L. Frølund 3 , N. Johansen 4 1 Research Centre for Prevention and Health, Glostrup University Hospital, Glostrup, Denmark; 2 Dermatology Clinic, Bagsværd, Denmark; 3 Allergy and Lung Clinic, Hellerup and Helsingør, Denmark; 4 In Vitro Diagnostics Business Unit, ALK-Abelló, Denmark Key words: allergic asthma; allergic rhinitis; diagnosis; IgE; diagnosis. A. Linneberg Research Centre for Prevention and Health Glostrup University Hospital 57 Ndr Ringvej Building 84/85 DK-2600 Glostrup Denmark Accepted for publication 19 July 2005 Allergy 2006: 61: 344–348 Copyright Ó Blackwell Munksgaard 2006 ALLERGY DOI: 10.1111/j.1398-9995.2006.00968.x 344