Title: Early changes in laboratory tests predict liver function damage in patients with moderate
coronavirus disease 2019: a retrospective multicenter study
Version: 1 Date: 29 Dec 2021
Reviewer's report:
In general, a potentially good impact may come from using risk prediction model in strategic
planning, mainly in the pandemics era. I have, however, some concerns regarding the
manuscript:
1) There are several grammar and commas misplacements that my difficult reader understanding
and interpretation  of the text.
2) Some statements lack reference citation.
3) Which definition did the authors use in the stratification of mild, moderate and severe disease?
Please make it clearer in the text.  Also, please make it clearer which admission did the authors
considered, hospital, ICU, etc.
4) How were patients selected to be included in the study? Was it a convenience sample? Please
address this matter as it may contribute to bias.
5) In which period did the study take place?
6) The authors propose a model based on liver dysfunction testing and use variables such as
AST, ALT, etc. However, the statement is that it was considered as liver function damage tests
the are outside the scope of reference values. Provided that a patient, for example, have a mildly
elevated AST/ALT, for example, about 1.5x the reference value, was this considered as liver
dysfunction? Please clarify in the text how the bias and potential confounders of other causes
of test alterations was addressed.
7) Did any included patients had previous liver disease or malnutrition, for example? This may
bias sample and score. How was this potential bias reduced in the analysis? Could the authors
elaborate?
8) In the liver damage group, please explicite in the text which variables were considered altered.
Also, the submitted table is very difficult to read properly. A suggestion would be to redesigned
it in order to make it clearer for readers.
9) In the discussion, authors make a statement about vaccine production in China. Please clarify
the correlation between this and the proposed discussion.
10) Could the authors explain the following period: "Platelets are involved in the body’s
coagulation process, and abnormal PCT levels can lead to coagulation dysfunction, confirming
that coagulopathy in patients with COVID-19 is related to liver function damage". Do authors
mean PCT can cause or aid in the detection of coagulation disorders? Also, the statement also
suggest that coagulopathy in COVID-19 is related only to liver damage. This is not true. Please
address this matter.
10) If feasible, an increase in sample size would make data and conclusion more robust in order
for the score prediction to indeed have a positive impact in clinical propaedeutics.
Title: Early changes in laboratory tests predict liver function damage in patients with moderate
coronavirus disease 2019: a retrospective multicenter study
Version: 1 Date: 29 Dec 2021
Reviewer's report:
In general, a potentially good impact may come from using risk prediction model in strategic
planning, mainly in the pandemics era. I have, however, some concerns regarding the
manuscript:
1) There are several grammar and commas misplacements that my difficult reader understanding
and interpretation  of the text.
2) Some statements lack reference citation.
3) Which definition did the authors use in the stratification of mild, moderate and severe disease?
Please make it clearer in the text.  Also, please make it clearer which admission did the authors
considered, hospital, ICU, etc.
4) How were patients selected to be included in the study? Was it a convenience sample? Please
address this matter as it may contribute to bias.
5) In which period did the study take place?
6) The authors propose a model based on liver dysfunction testing and use variables such as
AST, ALT, etc. However, the statement is that it was considered as liver function damage tests
the are outside the scope of reference values. Provided that a patient, for example, have a mildly
elevated AST/ALT, for example, about 1.5x the reference value, was this considered as liver
dysfunction? Please clarify in the text how the bias and potential confounders of other causes
of test alterations was addressed.
7) Did any included patients had previous liver disease or malnutrition, for example? This may
bias sample and score. How was this potential bias reduced in the analysis? Could the authors
elaborate?
8) In the liver damage group, please explicite in the text which variables were considered altered.
Also, the submitted table is very difficult to read properly. A suggestion would be to redesigned
it in order to make it clearer for readers.
9) In the discussion, authors make a statement about vaccine production in China. Please clarify
the correlation between this and the proposed discussion.
10) Could the authors explain the following period: "Platelets are involved in the body’s
coagulation process, and abnormal PCT levels can lead to coagulation dysfunction, confirming
that coagulopathy in patients with COVID-19 is related to liver function damage". Do authors
mean PCT can cause or aid in the detection of coagulation disorders? Also, the statement also
suggest that coagulopathy in COVID-19 is related only to liver damage. This is not true. Please
address this matter.
10) If feasible, an increase in sample size would make data and conclusion more robust in order
for the score prediction to indeed have a positive impact in clinical propaedeutics.
Please review this paper.
user
Title: Early changes in laboratory tests predict liver function damage in patients with moderate
coronavirus disease 2019: a retrospective multicenter study
Version: 1 Date: 29 Dec 2021
Reviewer's report:
In general, a potentially good impact may come from using risk prediction model in strategic
planning, mainly in the pandemics era. I have, however, some concerns regarding the
manuscript:
1) There are several grammar and commas misplacements that my difficult reader understanding
and interpretation  of the text.
2) Some statements lack reference citation.
3) Which definition did the authors use in the stratification of mild, moderate and severe disease?
Please make it clearer in the text.  Also, please make it clearer which admission did the authors
considered, hospital, ICU, etc.
4) How were patients selected to be included in the study? Was it a convenience sample? Please
address this matter as it may contribute to bias.
5) In which period did the study take place?
6) The authors propose a model based on liver dysfunction testing and use variables such as
AST, ALT, etc. However, the statement is that it was considered as liver function damage tests
the are outside the scope of reference values. Provided that a patient, for example, have a mildly
elevated AST/ALT, for example, about 1.5x the reference value, was this considered as liver
dysfunction? Please clarify in the text how the bias and potential confounders of other causes
of test alterations was addressed.
7) Did any included patients had previous liver disease or malnutrition, for example? This may
bias sample and score. How was this potential bias reduced in the analysis? Could the authors
elaborate?
8) In the liver damage group, please explicite in the text which variables were considered altered.
Also, the submitted table is very difficult to read properly. A suggestion would be to redesigned
it in order to make it clearer for readers.
9) In the discussion, authors make a statement about vaccine production in China. Please clarify
the correlation between this and the proposed discussion.
10) Could the authors explain the following period: "Platelets are involved in the body’s
coagulation process, and abnormal PCT levels can lead to coagulation dysfunction, confirming
that coagulopathy in patients with COVID-19 is related to liver function damage". Do authors
mean PCT can cause or aid in the detection of coagulation disorders? Also, the statement also
suggest that coagulopathy in COVID-19 is related only to liver damage. This is not true. Please
address this matter.
10) If feasible, an increase in sample size would make data and conclusion more robust in order
for the score prediction to indeed have a positive impact in clinical propaedeutics.
assistant