Review for 10.1186/s12876-019-0948-6 (2019)

Reviewer ’s report  
 
Title: A comparison of the diagnosis of gastroparesis in 4 hour ped iatric gastric emptying studies 
versus 2 hour studies  
 
Version: 0 Date: 29 Sep 2018  
 
Reviewer: Efstratios Saliakellis  
 
Reviewer's report:  
 
I would like to congratulate the authors for this very interesting study; it definitely adds more 
data in the field of gastroparesis in children and their optimal way of detecting delayed gastric 
emptying using the gastric emptying scintigraphy.  
 
The following areas need to be addressed, however, prior to considering the manuscript for 
publication:  
 
 
 
Background  
 
line 3 : it is important to add the nature of the the obstruction ie absence of mechanical 
obstruction along with the delayed emptying of either fluids and/or solids  
 
 
 
Methodology:  
 
Could the authors add in the methodology secti on whether an esophagogastroduodenoscopy, 
upper GI contrast series, blood tests (eg blood glucose, thyroid f unction tests, biochemistry) were 
performed prior to the gastric emptying scintigraphy?  
 
Were the patients on any medications that could affect gastr ic emptying time? If yes, were they 
advised to discontinue them and for how long prior to the test?  
 
Was a dynamic study performed to assess for fundic accommodation?  
 
Did authors collect data regarding the underlying diagnosis, co -morbidities? These data ne ed to 
be included  
 
Gastric emtptying study: Line 21 - reference is needed for the grading of the delayed gastric 
emptying  
 
Did authors perform a sample size calculation for the study to be of adequate power?  
 
Results:  
 
Plewase the authors need to include a table with demographics and cohort's caracheristics (eg 
age, gender, anthropometric data, underlying diagnosis, co -morbidities, outcome of previous 
investigations ie endoscopy) and I would also suggest to present the o utcomes of the gastric 
emptying scintigrpahy in a table rather than in a narrative form.  
 
 
I would like to ask the authors to assess the association between the major outcomes of the study 
ie gastric emptying time, GCSI, successful / unsuccessful completion of the test meal with 
certain variables such as age, gender, underlying diagnosis, cardinal symptom  
 
 
What was the main factor limiting the completion of the test meal within 10 minutes?  
 
 
Have Play Specialists been involved in order to improve co -operation du ring the study? If yes, 
was the latter significant?  
 
 
Page 9 - Table 1: what were the 'other' indications for the study?  
 
 
 
Discussion:  
 
I would like to ask the authors to further elaborate on the gastric emptying physiology (eg effect 
of caloric content, nutr ients,  composition and volume of the meal on gastric emptying time) and 
pathophysiology (eg fundic accommodation, antral motility) in order to further enrich their 
discussion.  
 
 
Additional results as per my previous suggestions also to be included in the di scussion  
 
 
 
 
 
 
 
 
 
 
 
 
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
No 
 
Are 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 manus cript 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 statistics  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Acceptable  
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, f ees, funding, or salary from an 
organisation that may in any way gain  or lose financial ly from the publication of this 
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation t hat may in any way gain or lose 
financially from the publication of this manuscript, either now or in the fut ure? 
 
3. Do you hold or are you currently applying for any patents  relating to the content of the 
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds or has applied for patents relating to the content of  the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing interests in relation to this paper?  
If you can answer no to all of the above, write 'I declare that I have  no competing interests' 
below. If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests  
 
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