OBJECTIVETo investigate the status of asthma control in the city and severity of asthma in children and to identify related factors.

METHODThis study was conducted in one children's hospital or tertiary hospital in each of the 29 provinces except Xinjiang and Xizang Autonomous Regions. Totally, 2960 parents with asthmatic children ages 0 to 14 years, and all had been diagnosed with asthma at least 3 months ago and the course was more than 12 months, who visited those hospitals were selected for the knowledge, attitude, and practice (KAP) questionnaire survey, and separated into the controlled asthma group and uncontrolled asthma group according to children's asthma conditions in the past 12 months. Multivariate analysis was carried out based on the answers to 28 tested factors; 2485 of 2960 questionnaires from 29 provinces were valid.

RESULTOf the 2485 valid questionnaires, 66.0% asthmatic children had asthma attacks in the past 12 months, 26.8% asthmatic children had visited the emergency department, 16.2% asthmatic children had been hospitalized. The total cost was significantly higher in the uncontrolled group than in contro group (χ² = 23.14, P < 0.01). Parents' education level, parents' KAP scores, regular visits for asthma control, knowledge of "3 or more times recurrent wheezing suggesting asthma", knowledge of "cough lasting for more than 4 weeks suggesting asthma", knowledge of "cough improved with bronchodilators suggesting asthma", knowledge of "awareness of using short-acting β₂ agonist for acute attack", avoiding contact with plush toys, adhere to use nasal steroid, inhaled corticosteroids/composite preparation, age of children and course of asthma in children are protective factors that affect asthma control and severity of asthma in children. Food allergies, eczema and family history of asthma are risk factors.

CONCLUSIONAsthma in many children was poorly controlled. Factors that affect asthma control and severity include parents' knowledge about asthma, exposure to adverse environment, the compliance with medication and regular visits for asthma control. Awareness and improvement the related factors about asthma control and severity can help leading asthma to a well-controlled status and reducing the severity of asthma.