Parent-reported ISAAC written questionnaire may underestimate the prevalence of asthma in children aged 10-12 years.

Objectives: The aim of the present study was to compare the validity of the International Study of Asthma and Allergies in Childhood (ISAAC) written (WQ) and audiovisual questionnaires (AVQ 3.0) in two age-groups (10-12 and 13-15 years, respectively).

Methods: The 13-15 year olds performed the self-completed the WQ and AVQ on the same day.

Changes in the prevalence of childhood asthma in seoul from 1995 to 2008 and its risk factors.

Purpose: To investigate the prevalence of asthma and determine its risk factors in elementary school students in Seoul.

Methods: A modified International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was used to survey 4,731 elementary school students from five areas in Seoul between April and October, 2008.

Results: In elementary school children, the lifetime and recent 12-month prevalence of wheezing were 11.