Author Contributions: All authors had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Voth, Reinhard, Bieber, and Wenzel. Acquisition of data: Voth, Landsberg, Betz, and Wenzel. Analysis and interpretation of data: Voth, Refke, Betz, and Wenzel. Drafting of the manuscript: Voth and Wenzel. Critical revision of the manuscript for important intellectual content: Landsberg, Reinhard, Refke, Betz, and Bieber. Administrative, technical, and material support: Voth, Landsberg, Refke, and Betz. Study supervision: Voth, Reinhard, Betz, Bieber, and Wenzel.