R1

Thank you for giving me the opportunity to review the article. The authors conducted a study on the determinants of skin carotenoid status using the Veggie Meter. There were crucial methodological concerns in the study, and I thought that it cannot be accepted for publication in the journal. I listed the major comments below.

Comments:

Abstract:

1. P1: The authors stated that “strong negative associations of CRS with weight and BMI (r2=0.11)”, but this cannot be said based on the results. Not only that, the r2 value was low to said about the association between the CRS and BMI.
2. P1: The conclusion statement of the Abstract was not match with the title. Materials and Methods:
3. P2: Why did the authors not set any exclusion criteria (e.g. complications, prescribed drugs and others) of this study except for age.
4. P2: Why did the authors not collect any clinical backgrounds of study participants (e.g. complications, prescribed drugs and others).
5. P2: The representativeness of the study population could be limited.
6. P2-3: The sample size calculation performed before study should be added.
7. P2-3: The authors should add the methods to interpret the results (i.e. coefficient, beta, and r2 values).

Results:

1. P5-6: The interpretation of the results (i.e. coefficient, beta, and r2 values) were inappropriate.

R2

Thank you for giving me the opportunity to review the revised version of this article. The authors conducted a study on the determinants of skin carotenoid status using the Veggie Meter. I thought that the authors revised the manuscript as far as possible, but there were crucial methodological concerns in this study. For example, there were no exclusion criteria and clinical backgrounds of the study participants, therefore, the reviewer (and also the authors) cannot interpret the results appropriately. Not only that, the interpretation of the results (results of statistical analysis) was inappropriate. This means that the authors did not consider the values of the correlation coefficients (i.e. there were negligible correlations with statistical significance). These problems cannot be overcome with revisions. Based on these reasons, I thought that it cannot be accepted for publication in the journal.