Review Reports

Round 1

Reviewer 1 Report

Thank you for inviting me to review the article titled “Urine di-(2-ethylhexyl) phthalate metabolites are independently related to body fluid status in adults: Results from a U.S. nationally representative survey”

 

I understand that the data used is around 20 years old now. However, that does not mean the authors have not done thorough work. I commend the authors for their hard work.

 

Criticisms:

Major:  Study does not provide sufficient evidence to prove a correlation between ECF/ICF ratio and eDEHP

While the p-value may be significant, that does not mean the model has provided the appropriate correlation.

 

e.g., Correlation values near 1 are considered the best possible fit.

In table 5, if I am reading the table correctly, the regression coefficient values ( s.e.) are 0.003  with a p-value of 0.044; while this may be statistically significant, a fit of 0.003 reports that the model almost fails to fit the data.

 

This is true for all values for ECF/ICF ratio in table 5, which may also be due to the limited sample size, and thus this should not be reported as a positive correlation. The study has not generated sufficient evidence for this and this correlation should be removed, rather this correlation should be considered a hypothesis-generating finding. Yes, it should be mentioned if the available data was the limiting factor.

 

In contrast, body fat % for women and eDEHP have a relatively good correlation.

 

Minor:

The table labeling is a bit tough to understand.

 

Table 1: I could not understand the numbers, eg. The Title mentioned MEHP(ug/g), and the numbers were 2.13(1.03); if 1.03 is ug/g, what is the unit of measurement of MEHP. Please clarify better.

 

Same for tables 2, 3, and 4.  Column headings need to be clearer.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Major points:

1. Abstract presents some results and conclusions, but they are all descriptive. What can we learn from these results and conclusions? 
2. For the introduction, could the authors highlight why the DEHP is selected and studied in a better way? Or please give some descriptions about the importance of DEHP in a clearer way.
3. This paper is descriptive, could authors give a conclusion and biological meaning from your data at the end of the discussion?

Minor points:

1.      Line 38, it is not clear why phthalates increase flexibility. 

2.      Line 39, is phthalate detected or are the metabolites of phthalate detected?

3.      Table 1 and 2, suggest separating each category by a line

4.      Table 2, why dose the lower BMI people have higher ratio? But higher body fat level shows higher ratio?

Author Response

Please see the attachment.

Author Response File: Author Response.docx