AUTHOR=Larsen Sofus C. , Rohde Jeanett F. , Olsen Nanna J. , Østergaard Jane N. , Heitmann Berit L. , Specht Ina O. 

TITLE=Attained body mass index among children attending rural outdoor or urban conventional kindergartens

JOURNAL=Frontiers in Psychology

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2023.1166512

DOI=10.3389/fpsyg.2023.1166512

ISSN=1664-1078

ABSTRACT=Objective: To examine whether children in rural outdoor kindergartens had attained a lower body mass index z-score (BMIz) and risk of overweight after school entrance compared to children in urban conventional kindergartens. 
Methods: A longitudinal observational study of 1544 children from outdoor kindergartens and 1640 from conventional kindergartens. The mean age at kindergarten enrolment was 3.5 years (SD: 0.9) in the outdoor kindergartens and 3.6 years (SD: 1.0) in the conventional kindergartens. Anthropometry was measured after school entry by school health nurses when the children were 6 to 8 years old. Attained BMIz was included as the primary outcome. Risk of attaining overweight (including obesity) was included as a secondary outcome. Register-based information was available on potential confounding factors. Linear and logistic regression models were used to assess group differences in outcome measures. 
Results: Our basic models, with information on outcome, kindergarten type and birth weight, showed a borderline statistically significantly lower attained BMIz (-0.07 [95% CI: -0.14, 0.00], P=0.060) and a lower risk of overweight (adjusted risk ratio: 0.83 [95% CI: 0.72, 0.97], P=0.016) among children attending outdoor kindergartens. However, when adjusting for sociodemographic factors and parental BMI, there was no evidence of differences in attained BMIz (P=0.153) or overweight (P=0.967).
Conclusion: When considering confounding factors, our findings indicate no differences in attained BMIz or risk of overweight after school entry among children attending rural outdoor kindergartens compared to those attending urban conventional kindergartens.