Review for 10.1186/s12876-020-01396-8 (2020)

Reviewer’ s report
Title: Psychometric properties of the Persian version of the celiac disease adherence
test questionnaire
Version: 0Date: 04 Jun 2020
Reviewer: Anil K Verma
Reviewer's report:
Manuscript number: BMGE-D-20-00309
Title: Psychometric properties of the Persian version of the celiac disease adherence test (CDAT)questionnaireManuscript type: Research articleOpinion:In this study, the authors have validated the CDAT questioner (translated from the EnglishVersion) for Iranian CD patients (Persian version). The authors have translated the Persian versionof the questionnaire by two independent Persian translators then by Persian to English translators.Finally, the practicality of the questionnaire was evaluated by several tests, and the results wereshared with the original author (English version. I am happy with the study design. However,while reading the article, I found several points that need further clarification.Comments to the author:Major comment:Comment#1: In this study, the authors have correlated the CDAT questionnaire by the tTG test. Asfar as I know, there is no recognized test so far to test adherence. A duodenal biopsy is the goldstandard test that was not considered. I would take a weakness of the study. However, I also
understand that performing a biopsy in 230 study patients (following GFD) is not easy or would
take too much time with a high rate of refusal. I also agree that tTG (IgA) is the most reliable testused so far for this purpose. I appreciate that the authors have mentioned this in the manuscript.However, the authors should mention the level of tTG test (how many were 18 (if any) ) with thetTG unit.Comment#2 (Page no. 7): There were 230 CD patients (on GFD for 4 years) were included for thestudy however the authors have not mentioned their compliance. Were those patients underwent acomplete diet evaluation from a celiac expert dietician?
Minor comments
Comment#3 (Page no. 8, line no 23): The authors should give the AESKULISA kit code, countrylocation. The authors must mention the unit of the AESKULISA tTG test.Comment# 4: The authors should mention the study duration (when the study was conducted).Page no. 6 (Method and materials)Comment#5 (Page 7, Line no. 34-60): Apart from the age, were there other criteria? like patientswith good compliance? Were there any exclusion criteria involved? (Assessment of constructvalidity)Comment#6 (Page no. 8, Line no. 20-23): ' immunoglobulin A tissue transglutaminase (IgA anti-
tTG)? Is it the name of one test? Please mention this in the manuscript correctly.
Comment#7: Reference no.2 is not appropriate probably it is a cross-reference. It should be recited
with the corrected reference.Comment#8 (Page 5, Line no. 23): The authors have mentioned studies, but cited only onereference. There should be more than one reference.Comment#9 (Page 5, line no. 50): 'This is wile the……' this line is not clear.Comment#10 (Page no. 6, Line no. 10): Line 'as translated to Persian and its face' This line is notclear to understand.Comment#11 (Page no. 10, line no. 9): I suspect the line 'The Spanish version of the questionnairehad moderate internal consistency' has incorrect reference. The authors should cross-check.
Comment#12: This is advice only if the authors have been helped by the original author (as the
authors have mentioned). The study authors may acknowledge the original author in theacknowledgment section. However, this is fully dependent on the author's decision.
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.
Yes
Are 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 furtherassessment in your comments to the editors.
Not relevant to this manuscriptQuality of written English
Please indicate the quality of language in the manuscript:
AcceptableDeclaration of competing interests
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