*4.6. Statistical Analysis*

All results were presented as mean ± standard deviation (SD). Normality was analyzed by the Shapiro–Wilk test. If the data showed a normal distribution, differences between CPO and placebo groups were assessed by an unpaired *t*-test, and intra-group changes were evaluated by paired *t*-test. If the data did not show a normal distribution, we performed a Wilcoxon signed-rank test to analyze inter-group differences, and Wilcoxon rank sum test to analyze between-group differences. No additional analysis was performed. Probabilities less than 5% (\* *p* < 0.05 and \*\* *p* < 0.01) were considered to be statistically significant. Statistical analyses were performed with JMP (version 13).

**Author Contributions:** N.I. and S.S. designed the concept of this study. N.I. interpreted the results and prepared the manuscript. F.U. supervised this study. All authors discussed the results and commented on the manuscript.

**Funding:** This research received no external funding.

**Acknowledgments:** We thank DRC Corporation for clinical management and analysis of the results as a practitioner for this study. We also thank Yuri Okano (CIEL Corporation), who supervised this study, and Yuriko Oda, Ayano Imai and Yoshiyuki Shirakura (FUJIFILM Corporation) for valuable discussion.

**Conflicts of Interest:** N.I., S.S. and F.U. are employees of FUJIFILM Corporation, a sponsor and funder of this study. As described in Author Contributions, these employees designed the concept of this study, interpreted the results and prepared the manuscript.
