BMI WC WHR Model 1 .016 .011 Model 2 .022 .017 Model 1 .019 .012 Model 2 .040 .019 Model 1 .015 .013 Model 2 .027 .022 Girls P .14 .20 .11 .03 .24 .21 -.01 to .04 .009 .009 -.01 to .06 .027 .013 .0 to .04 .0 to .08 .008 .011 .029 .015 -.01 to .04 .020 .012 -.02 to .07 .024 .018 Cuypers et al. BMC Public Health 2012, 12:820 http://www.biomedcentral.com/1471-2458/12/820 found in girls, but not in boys. In boys, participation in social activities was significantly positively associated with z-scores of BMI and WC and near-significant with z-scores of WHR in adulthood (Additional file 1: Table S4 and Table S5). In the same models including only those with normal weight (n = 1123) at baseline, the analyses pictured simi- lar results, but now the associations were statistically sig- nificant (Table 2) in relation to the cultural activities. In an additional model (Additional file 1: Table S6) we excluded “watching TV or a video” as a component from the index cultural activities. In the model 2 adjusted for relevant confounders the effect estimates moved slightly toward zero from -.040 (−.08 to 0) to -.034 (−.07 to 0) and from -.058 (−.11 to -.01) to – .046 (−.08 to -.01) for the z-scores of WC and WHR respectively. In relation to the social activities the confidence inter- vals became broader (Table 3). Participation in social ac- tivities in girls was significantly positively associated with z-scores of WC in adulthood (Table 3). In boys the relationship between participation in social activities and BMI z-scores was still significant and near significant with WC. In addition, the associations for all activities separately toward the outcome showed the same direc- tion in linear regression models as for the indices of cul- tural and social activities. We have chosen to show the results for the models in- cluding only normal weight adolescents at baseline in Table 2 Associations between the index for cultural activities at baseline and the z-scores of body mass index (BMI), waist circumference (WC), and waist-hip ratio (WHR) eleven years later as adults Girls P B SE CI (95%) B SE Boys P BMI WC WHR Model 1 -.015 .013 .25 -.04 to .01 -.015 .013 .25 Model 2 -.011 .019 .58 -.05 to .03 .007 .020 .74 Model 1 -.028 .015 .05 Model 2 -.040 .021 .05 -.06 to 0 -.08 to 0 -.012 .014 .36 .001 .020 .97 Model 1 -.048 .016 .002 -.08 to -.02 -.020 .017 .23 Model 2 -.058 .025 .02 -.11 to -.01 .003 .023 .88 Girls n = 603; Boys n = 520. Excluded: overweight and underweight, pregnant, disabled physically or psychologically in daily activities. Model 1 Unadjusted effect of exposure on the outcome measure at follow-up Model 2. Adjusted pubertal development at baseline, physical activity change from adolescence to adulthood, and socio-economic status at follow-up. Cultural activities: reading a book you liked, listening to music or played an instrument longer than 15 min, watching TV or a video, and doing homework or school tasks longer than an hour. We assigned values from 1 to 4 for each answer-category regarding frequency (Not once (1), Once (2), 2–3 times (3), 4 times or more (4) in the last 7 days) and made a continuous variable by adding the scores for each activity (range 4–16). Employed GEE linear type model. (N: 1123 normal-weight adolescents). CI (95%) -.04 to .01 -.03 to .05 -.04 to .01 -.04 to .04 -.05 to.01 -.05 to .04 Page 5 of 10 Boys P .37 .05 .46 .06 .12 .18 CI (95%) -.01 to .03 .0 to .05 -.01 to .03 .0 to .06 -.01 to .04 -.01 to .06 Table 3 Associations between the index for social activities at baseline and the z-scores of body mass index (BMI), waist circumference (WC), and waist-hip ratio (WHR) eleven years later as adults B SE CI (95%) B SE Girls n: 603; Boys n: 520. Excluded: overweight and underweight, pregnant, disabled physically or psychologically in daily activities. Model 1 Unadjusted effect of exposure on the outcome measure at follow-up. Model 2. Adjusted in for pubertal development at baseline, physical activity change, socio-economic status at follow-up. Social activities: visiting some one you know, receiving a visitor, being out for more than two hours with friends, being at a meeting or training in an organization or a club. We assigned values from 1 to 4 for each answer-category regarding frequency (Not once (1), Once (2), 2–3 times (3), 4 times or more (4) in the last 7 days) and made a continuous variable by adding the scores for each activity (range 4–16). Employed GEE linear type model. (N: 1123 normal-weight adolescents). the paper (Tables 2 and 3) and have attached data for the whole population in the Additional file 1: Tables S4 and S5. Interaction between cultural and social activities No significant correlation (r =0.05, p = 0.12 and r = 0.03, p = 0.39 in girls and boys respectively) and no interaction (p = 0.60) was noted between participation in social and cultural activities, indicating that cultural and social leis- ure time activities were independent concepts in their relationship to the adiposity measures. Moderation of the effect of susceptibility genes for obesity on adiposity measures by leisure time activities The GPS was significantly associated with both continu- ous traits z-scores of BMI (0.03 SD/allele, 95% CI: 0.01 to 0.05, p = 0.008) and z-scores of WC (0.03 SD/allele, 95% CI: 0.06 to 0.05, p = 0.012) at follow-up. Also, in those with low cultural activity, the GPS had a substantial and significant (p for interaction = 0.06) higher effect size (SD/allele: 0.050 (95% CI: 0.02 to 0.08) versus 0.005 (95% CI: -0.03 to 0.04)) (Figure 1) on BMI 11 years later compared to the group with high culturally activity. The same trends were seen for WC (Figure 2). We found no significant interactions between neither gender nor social activity participation and the GPS in association with adiposity measures in adulthood.