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Acknowledgments
SHIP is part of the Community Medicine Research net of the University of Greifswald, Germany, which is funded by the Federal Ministry of Education and Research (grants no. 01ZZ9603, 01ZZ0103, and 01ZZ0403), the Ministry of Cultural Affairs and the Social Ministry of the Federal State of Mecklenburg-West Pomerania. This work was also funded by the German Research Foundation (DFG: GR 1912/5-1).
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Schmidt, C.O., Ittermann, T., Schulz, A. et al. Linear, nonlinear or categorical: how to treat complex associations? Splines and nonparametric approaches. Int J Public Health 58, 161–165 (2013). https://doi.org/10.1007/s00038-012-0363-z
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DOI: https://doi.org/10.1007/s00038-012-0363-z