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: 22 Aug 2018  
 
Reviewer: Lorenzo Biassoni  
 
Reviewer's report:  
 
Clinically relevant manuscript, helpf ul towards standardisation of the solid phase of the gastric 
emptying study.  
 
 
 
General impression  
 
The study is well designed. The two points made by the authors are valid and important. The 
methodology is adequate. In my view, the manuscript needs rephrasin g of some sentences - not 
very clear in the current version - and some more details on the technical acquisition of the 
gastric emptying study (which I am sure can be easily provided by the two co -authors affiliated 
to the Radiology department).  
 
 
 
Title  
 
Ashley K Sherman M.A is affiliated to the Health and Outcomes Research Division (c); a small 
"c" is needed before "Health Services and Outcomes Research Division" at page 1, line 9.  
 
 
 
Methods  
 
Study Design  
 
page 6, 1st paragraph: A think one sentence describing the aim of the prospective study at this 
point would be helpful (for example: "The prospective study aimed to compare the results of the 
gastric emptying study with the data collected with the CGSI questionnaire").  
 
 
Gastric Emptying Study  
 
page 6, line 9: the name of the radiopharmaceutical (Tc -99m-nanocolloid? Tc -99m-sulfur 
colloid?) used to radiolabel the solid test meal is not given (only the isotope - Tc-99m). This 
must be specified. Some details of the scanner used for the studies shoul d also be given. I can see 
that only anterior images were acquired: this suggests to me that the authors used a single head 
gamma camera? The model and the manufacturer should be specified. Also, for how long was 
the study acquired? What was the matrix use d? 
 
 
 
Questionnaire  
 
page 7, lines 1 -3: I think this sentence would benefit from re -phrasing. For example: "For the 
prospective study, a symptom based questionnaire was used. Two questionnaires were produced, 
one for parents of children aged between 2 and 12 years, who answered the questions; another 
questionnaire was tailored older patients aged between 13 and 17 years. "  
 
 
 
Data analysis  
 
line 18: (...)patients were included from both the retrospective and the prospective parts of the 
study. For the correlation  of gastric emptying findings with symptoms only data from the 
prospective study was analysed.  
 
 
 
Results  
 
page 8, line  13: again, the full name of the radiopharmaceutical (not just the isotope) is 
necessary.  
 
page 9, line 7 -8: Of the 95 participants with norm al studies (...), 15% (14/95) had abnormal 
studies at 4 hours.  
 
 
 
Conclusion  
 
page 12, line 19,20: This sentence (Ultimately,...) is not a statement that comes as a result of the 
study, but I suppose is a thought of the authors regarding the role of the gastr ic emptying study in 
pediatric gastroenterology. Therefore, I think it would be good to make this clear. This could be 
achieved by introducing something like "Ultimately, we think that the clinical utility...". 
Alternatively, this sentence could be taken o ut altogether.  
 
 
 
 
 
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.  
 
Yes 
 
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:  
 
Needs some language corrections before being published  
 
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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