Authors’ contributions
Hiroshi Murayama, Shusaku Sasaki, and Yuta Takahashi conceived and designed the study. Hiroshi Murayama, Mai Takase, and Atsuko Taguchi collected the data. Hiroshi Murayama analyzed the data. Hiroshi Murayama, Shusaku Sasaki, and Yuta Takahashi interpreted the results. Hiroshi Murayama drafted the manuscript. Shusaku Sasaki, Yuta Takahashi, Mai Takase, and Atsuko Taguchi critically revised the manuscript for intellectual content and provided comments on previous versions of the manuscript. All authors read and approved the final version of the manuscript.