Signs of high air humidity, as well as of structural building dampness, are common in multi-family buildings in Stockholm. Reports of building dampness in dwellings is related to a pronounced increase of symptoms compatible with the SBS, even when adjusted for possible confounding by age, gender, population density, and building-related risk factors.

Risk factors for rhinitis, asthma and respiratory infections in the home environment were studied by a questionnaire survey. Totally 5775 occupants (≥18 years old) from a stratified random sample of multi-family buildings in Sweden participated (46%). 51.0% had rhinitis in the last 3 months (current rhinitis); 11.5% doctor diagnosed asthma; 46.4% respiratory infections in the last 3 months and 11.9% antibiotic medication for respiratory infections in the last 12 months. Associations between home environment and health were analyzed by multiple logistic regression, controlling for gender, age and smoking and mutual adjustment. Buildings constructed during 1960–1975 were risk factors for day time breathlessness (OR = 1.53, 95%CI 1.03–2.29). And those constructed during 1976–1985 had more current rhinitis (OR = 1.43, 95%CI 1.12–1.84) and respiratory infections (OR = 1.46, 95%CI 1.21–1.78). Cities with higher population density had more current rhinitis (p = 0.008) and respiratory infections (p<0.001). Rented apartments had more current rhinitis (OR = 1.23, 95%CI 1.07–1.40), wheeze (OR = 1.20, 95%CI 1.02–1.41), day time breathlessness (OR = 1.31, 95%CI 1.04–1.66) and respiratory infections (OR = 1.13, 95%CI 1.01–1.26). Living in colder parts of the country was a risk factor for wheeze (p = 0.03) and night time breathlessness (p = 0.002). Building dampness was a risk factor for wheeze (OR = 1.42, 95%CI 1.08–1.86) and day time breathlessness (OR = 1.57, 95%CI 1.09–2.27). Building dampness was a risk factor for health among those below 66 years old. Odor at home was a risk factor for doctor diagnosed asthma (OR = 1.49, 95%CI 1.08–2.06) and current asthma (OR = 1.52, 95%CI 1.03–2.24). Environmental tobacco smoke (ETS) was a risk factor for current asthma (OR = 1.53, 95%CI 1.09–2.16). Window pane condensation was a risk factor for antibiotic medication for respiratory infections (OR = 1.41, 95%CI 1.10–1.82). In conclusion, rhinitis, asthma and respiratory infections were related to a number of factors in the home environment. Certain building years (1961–1985), building dampness, window pane condensation and odor in the dwelling may be risk factors.

The aim was to develop a multiple logistic regression model to identify multi-family houses with an increase of sick building syndrome (SBS). In Stockholm, 609 multi-family buildings with 14,235 dwellings were selected by stratified random sampling. The response rate was 77%. Multiple logistic regression analysis was applied, adjusting for ownership of the building, building age and size, age, gender, and atopy. Females, subjects with allergy, those above 65 yr, and those in new buildings reported significantly more SBS. Subjects owning their own building reported less SBS, but the relationship between ownership and building age was strong. A regression model, including factors with a high explanatory value was developed. According to the model, 5% of all buildings built before 1961, 13% of those built 1976-1984, and 15% of those built 1985-1990 would have significantly more SBS than expected. In conclusion, SBS is related to personal factors, building age, and ownership of the building. To identify multi-family buildings with more SBS than expected, it is necessary to adjust for ownership and population characteristics.

The aim was to develop and validate a standardized questionnaire - the Stockholm Indoor Environment Questionnaire (SIEQ). The validation procedure was based on sociological principles and test procedures for validation. The indicators of indoor environment are air quality, thermal climate, noise, and illumination. The indicators of health are symptoms comprised in the sick building syndrome (SBS). The questionnaire also contains questions about the apartment, individual behavior, and personal factors. The everyday language describing the building and its function was first obtained by qualitative personal interviews, then by standardized questions. The interview questionnaire was transformed into a postal self-administered questionnaire. The reduction of the questionnaire was based on correlation analysis. It was found that to obtain a good validity, general questions are not sufficient, but specific question on perceptions and observations are needed. Good test-retest agreement was found both on an area level, building level, and individually. For each indicator, a set of questions are constructed and validated. SIEQ has been used in several studies, and the results are presented in graphic problem profiles. Reference data has been calculated for the Stockholm area.