Review for 10.1186/s12876-017-0601-1 (2017)

Reviewer ’s report  
 
Title: Costs and quality of life of small incision -open cholecystectomy and laparoscopic 
cholecystectomy. An expertise -based randomised cont rolled trial.  
 
Version: 1 Date: 20 Apr 2016  
 
Reviewer: Stefan Breitenstein  
 
Reviewer's report:  
 
Summary  
Authors analyzed costs and quality of life data of a previously published  (British Journal of 
Surgery) randomized controlled trial comparing small incision open cholecystectomy (SIOC) 
versus laparoscopic cholecystectomy (LC).172 patie nts with LC  and 151 SIOC were evaluated. 
While total costs were significantly lower in the SIOC group quality of life did not differ 
between patient collectives.  
 
Comments to the authors  
This manuscript represents an additional analysis of the previously published study comparing 
two techniques of cholecystectomy. The focus of the current comparison involves cost analysis 
and quality of life until 30 days after surgery.  Although the autho rs focus on attractive surgical 
issues, this manuscript has major flaws which need to be addressed by the authors.  
 The method section in general is too long (4,5 pages). I suggest reducing at least 35% .  
 
 What are the primary and the secondary endpo ints of the study. Endpoints need to be 
precisely defined, since the primary endpoint reflects the basis of the power calculation.  
 
 Why were patients with severe complications excluded from the study? This is questionable 
and makes no sense to me. An "in tention to treat" analysis of all patients remains the most 
important methodological aspect of a randomized controlled trial.  This opinion may need to 
be clarified by an epidemiologist. The focus on one simple and reproducible intention to treat 
analysis would primarily prevent any confusion and secondarily shorten and clarify the 
content of the manuscript .  
 
 Authors define complications Grade ≥3b as „relevant".  Consequently, postoperative 
interventions such as puncture of drainage of abscesses as well as  ERCP (classified as 3a) 
are not considered as relevant. In cholecystectomy it would make much more sense to 
distinguish between complications ≤2 (minor) and ≥3a (major).  
 
 Fig 1 was already published in a previous paper of this study in BJS. It needs  to be discussed 
with the editor of BMC as well as with BJS, if it is beneficial to publish the same figure 
again.  
 
 Regarding economic outcome, I miss the sub -analyses of emergency versus elective 
treatments as well as the comparison of patients with com plication against patients without 
complications. As discussed in the manuscript it is a reasonable assumption, that these two 
factors influence the economic results. Therefore, a specific analysis is of high interest.  
 
 „Written informed consent was obta ined"  is repeated in the text.  
 
 What is the definition of a pragmatic RCT as mentioned in the discussion section?  
 
 The level of experience of the surgeons needs to be precisely declared. Specific surgeons 
were defined only for SIOC and others only for  LC. Is this kind of specialization reasonable, 
or does it reflect a low level of expertise of the surgeons. I suppose that experts for a 
cholecystectomy surgical procedure are also able to perform either open or laparoscopic 
cholecystectomy.  
 
 A paragra ph on limitations is missing in the discussion. Please declare all limitation of the 
current study.  
 
 In the summary sentences at the beginning and at the end of the discussion section the 
sequence of findings is not consistent with the sequence of the re sults.  In the entire 
manuscript costs are described prior to findings on QoL. While in the summarization QoL 
appears first suggesting a priority of this aspect.  
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
No 
 
Does the work include the necessary controls?  
If not, please specify wh ich 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.  
 
Unable to assess  
 
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 further  
assessment in your comments to the editors.  
 
Not relevant to this manuscript  
 
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, fees, funding, or salary from an  
organisation that may in any way gain or lose financially from the publication of this  
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares  in an organisation that may in any way gain or lose  
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents relating to the content of the  
manuscript?  
 
4. Have you recei ved 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.  
 
I agree to the open peer review policy of the journal. I understand that my name will be included  
on my report to the authors and, if the manuscript is accepted for publication, my named report  
including any attachments I upload will be posted on the website along with the authors ' 
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CC-BY license ( http://creativecommons.org/licenses/by/4.0/ ). I understand that any comments  
which I do not wish to be included in my named report can be included as confidential comments  
to the editors, which will not be published.  
 
I agree to the open peer review policy of the journal