CAN SUBJECTS WITH A POSITIVE ALLERGEN SKIN-TEST BE SELECTED BY A SHORT QUESTIONNAIRE - THE GLOSTRUP ALLERGY STUDY, DENMARK

The objective was to evaluate a postal questionnaire screening procedu re for selection of subjects with positive reactions to skin prick tes ts with common allergens. The project consisted of a screening, with s ubsequent skin prick test of two selected groups. The setting was the Glostrup Population Studies institute in Copenhagen, Denmark. Particip ants in the screening included 8000 subjects, aged 15-69 years. The su bjects were randomly selected from the population of western Copenhage n County, Denmark. From the 6998 respondents (87.5%), 793 subjects wer e randomly selected (Random Group), and 788 subjects were chosen on th e basis of their answers to the questionnaire (Symptom Group). Both gr oups were invited to take skin prick tests. Attendance rates were 75.5 % (Random Group) and 80.6% (Symptom Group). The main outcome measures were responses (yes or no) to the specific questions and the subjects' skin reaction (positive or negative). The association between symptom s and skin reactivity, adjusted for the effects of sex and age, was su mmarized by odds ratios. Symptoms on exposure to allergens were highly associated with positive skin reactivity. In the Symptom Group the pe rcentage of subjects with at least one positive skin reaction was 57.7 %, which was twice as much (28.4%) as in the Random Group. The results show that it was possible to select a group with high skin reactivity on the basis of the symptoms reported in the screening. Questions abo ut exposure to allergens were the most appropriate for selection of th is group.