Review for 10.1186/s12876-020-01400-1 (2020)

Reviewer’ s report
Title: Evaluation of NAFLD and fibrosis in obese patients –a comparison of histological and
clinical scoring systems
Version: 0Date: 15 Apr 2020
Reviewer: Philipp Schwabl
Reviewer's report:
Schmitz et al describe a straight forward and well conducted study comparing different
histological and non-histological scores to assess NAFLD/NASH in a prospective study designwith retrospective data analysis. However there are some issues which need attention:
1) A very similar set of author has recently published a very similar study (Alizai PH, Lurje I,
Kroh A, Schmitz S, Luedde T, Andruszkow J, Neumann UP, Ulmer F. Noninvasive Evaluation ofLiver Function in Morbidly Obese Patients.Gastroenterol Res Pract. 2019 Feb 3;2019:4307462.) using very similar methods and the sameethics approval (EK 312/11). However, number of patients has increased meanwhile from 102 to141.In case the data of the 102 patients has already been published, I strongly recommend to clearlydeliniate between these two papers in order to avoid double reporting (e.g. of APRI and NAS)which are mentioned in both manuscripts.Moreover, in case it is true, this reporting bias must be mentioned somewhere in the manuscript.I also recommend to perform a plagiarism-check, as some sections in the background and methodsare written very similar to the above mentioned manuscript.
2) Table 1: Fascinating that only 35.4% of patients had diabetes mellitus. How were patients
identified to suffer from diabetes mellitus? Where all patients tested (e.g. OGTT?) Where DM1and DM2 differenciated?
3) An overall summarizing table including cut-offs, sensitivity, specificity, AUROC etc. would be
a very nice addition to this manuscript.
4) Transcutaneous and transjugular liver biopsies always bare the risk of being not representative
(and are especially difficult in such obese patients). While you discuss this issue, sample size and/or number of portal tracts of your studied samples is not reported and thus missing. Please providethis data.
Minor comments:
1) What was the time frame between recording of serum parameters and surgery?2) Since the word "race" has a somewhat negative connotation, maybe replace it with "ethnicity".3) When was Limax testing performed?4) Table 1: please write arterial hypertension, not only hypertension since there exist several types
of hypertension.
5) Table 1: please unify the number of decimals.
6) Page 16, row5: "patients with a stage 4 fibrosis" / Page 18, row1: "between no fibrosis and stage4 fibrosis" -> according to Figure 4 and previous text there were no cirrhotic patients (F4). Pleaseclarify.7) Could you identify "risk factors" for serious misclassification?8) Could you suggest/develop an algorythm of combined scores for clinicians treating morbidlyadipose patients (who are not necessarily hepatologists) ultimately leading the decision tree: (1)definite NASH -> check for presence of cirrhosis / monitor for HCC, (2) unsure NASH -> performbiopsy, (3) definitely no NASH -> continue clinical monitoring.
Are the methods appropriate and well described?
If not, please specify what is required in your comments to the authors.
YesDoes the work include the necessary controls?
If not, please specify which controls are required in your comments to the authors.
YesAre the conclusions drawn adequately supported by the data shown?
If not, please explain in your comments to the authors.
YesAre you able to assess any statistics in the manuscript or would you recommend an
additional statistical review?
If an additional statistical review is recommended, please specify what aspects require further
assessment in your comments to the editors.
I am able to assess the statisticsQuality of written English
Please indicate the quality of language in the manuscript:
AcceptableDeclaration of competing interests
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