1. SEARCH School Environment And Respiratory health of CHildren an international research project within the “Indoor Air Quality in European Schools. Preventing and reducing respiratory diseases” programme

2. INTERNATIONAL COLLABORATION ADVANTAGES Combination of experience Combination of resources Bigger datasets, stronger associations DISADVANTAGES Different possibilities Quality assurance/ quality control needed

3. OBJECTIVES to assess the associations between the school environment and the children’s (respiratory) health to make recommendations for improving the quality of school environment

4. STUDY DESIGN: cross-sectional Exposure assessment measurement of the indoor air quality in the school questionnaire on the class-room and time spent there questionnaire on the school building and its maintenance questionnaire on the home environment Health assessment symptom questionnaire (cough, wheeze, asthma dg, allergy) with questions on confounding factors, too lung function measurement other (laboratory tests, e.g. nasal smear test) (ethical approval may be needed!)

5. STUDY DESIGN: cross-sectional Advantages: Cheap (relatively) Quick and can be easily performed (relatively) Reasonable number of participants Disadvantages: Time-link between exposure and health outcome can not be determined Causal relationship can not be established (only hypothesis can be set up, confirmed by statistical analysis)

6. DATA EVALUATION 1. Determination of prevalences (frequency of children with various respiratory symptoms or impaired lung function) 2. Associations between the presence and quantity of various pollutants and the prevalences (look for dose-response relationships!) - by multivariate logistic regression (Odds Ratios, OR and their 95% confidence intervals, 95% CIs) - or linear regression

8. SCHOOL SELECTION Number of schools per country: 10 Number of children per school: 100 Age of the children: 8-9 years (3rd grade) Selection criteria to be decided, whether by – symptom prevalence - polluted vs, clean environment - building characteristics (new/old or light/traditional construction)