Subjects
A total of 618 children (7 years-old) from 11 randomly selected elementary schools in Seongnam City (Korea) were enrolled between June and July 2016. Each participant’s parents were asked to respond to the questionnaires prior to a physical examination and blood sampling. 408 children (66.0%) responded to the questionnaire and 305 (74.8%) agreed to the blood test. Thus, 248 children who provided questionnaire data, skin prick test (SPT) results, and blood samples participated in the study.

Study protocol

Pediatric allergy specialists and trained field technicians performed the physical examinations, SCORAD score assessments,15SPTs, and collected blood samples. The presence of current atopic dermatitis was diagnosed using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire,16 based on symptoms during the previous 12 months. The study protocol was approved by the Institutional Review Board of CHA University (2016-04-031) and written informed consent documents were obtained from all parents or guardians of children who participated.