Additional file 1: Table 6. Multinomial regression of body mass index classes (normal weight category as reference) in function of age, gender, educational level and lack of physical activity, Belgian population ≥ 18 years – underweight population was excluded, BHIS2013-IMA2013-2017 – the model includes the confounders that were significant after backwards stepwise elimination (N= 4,504). Table 7. Socio-demographic characteristics by body mass index category, Belgian population ≥18 years, health interview survey 2013 for population included in the multivariate regression (with no missing values in physical activity and educational level). Table 8. Chronic disease in function of available confounders – coefficient (standard error), Belgian population ≥ 18 years – underweight population was excluded, BHIS 2013-IMA2013-2017 – the model includes the confounders that were significant after backwards stepwise elimination. Table 9. Cost of absenteeism in function of body mass index classes adjusted for age, gender, ...