Review for 10.1186/s12876-016-0522-4 (2016)

Reviewer ’s report  
 
Title: Effect of mobile phone reminder messages on adherence of stent removal or exchange in  
patients with benign pancreaticobiliary diseases: a prospectively randomized, controlled study  
 
Version: 0 Date: 12 Jun 2016  
 
Reviewe r: James Tabibian  
 
Reviewer's report:  
 
In this retrospective study, the authors aimed to evaluate the effect of monthly mobile phone 
texting as an intervention to remind patients who had undergone plastic or cSEMS stent 
placement for ben ign pancreatobiliary disease of the need for stent removal/exchange.  The 
primary outcome was adherence to stent removal/exchange within the pre -determined timeframe. 
This is an intriguing and clever study of an easily overlooked yet important topic.   The  effort by 
the others is laudable, and the study design is clean and effective.  The study may have been 
underpowered to detect differences in the secondary ("hard") outcomes, but nevertheless these 
preliminary findings are valuable.  Comments and suggesti ons, some of which can be easily 
resolved and will strengthen the manuscript, are noted here:  
 
 
 
 
Abstract:  
 
- Would suggest using present tense for verbs in the introduction section.  
 
 
- The analytical methodology should be explained somewhat further in the meth ods section 
(as permitted by word count limitations); e.g. did the authors use chi -square for analyses 
(yes/no stent exchange/removal within appropriate timeframe)?  
 
 
 
Introduction:  
 
- The authors might consider removing the phrase "late -stage" from the first paragraph.   
 
 
- Is it accurate to say that the main worry with covered metal stents is failure of stent 
removal?  This is true with uncovered and partially covered stents, but much less so with 
covered.  The "main worry" would be stent migration and to a lesser degree st ent 
occlusion (e.g. with ingesta).  
 
- The following sentence is a run -on (needs a comma separating two independent clauses), 
"In addition, endoscopic management might thus be technical challenging and the 
treatment cost would be increased.", and "technically  challenging" would be the correct 
descriptor.  
 
 
- -"it was believed that the patient -centered outcome"which outcome(s) are the authors 
referring to?  
 
 
 
Methods:  
 
- The authors may want to add "at the discretion of the attending endoscopist" (or whoever 
made the f inal decision) at the end of the sentence, "The number and type of the stents 
was determined based on the characteristics of stricture or diseases."   
 
 
- How did the authors know a priori that, "The adherence in SMS group was about 80%."?  
Or was this simply  an estimate?  This should be clarified.  
 
 
- As alluded to in the abstract, the statistical methods need to be elaborated.  For example, 
what type of multivariable analysis was used?  Logistic regression, Linear regression, 
Cox proportional -hazards?  This ne eds to be specified.  In addition, how did the authors 
chose which variables would be entered in the model?  Was this simply backward 
stepwise?  Mixed?  Were some variables forced into the model?  
 
 
 
Results:  
 
- Could the authors add some granularity to this po rtion by including numerical data: "No 
difference was found regarding FCSEMS removal adherence between the two groups. 
There were also no differences between the two groups regarding stent -related 
complications, such as cholangitis, stent migration and rec urrent abdominal pain (all 
p>0.05)."?  Or at least more clearly make reference to Table 2 for these purposes.  
 
 
Discussion:  
 
- It is unclear what the authors intend to say in the sentence, "It is suggested that these 
stents  should be removed or exchanged wit hin 3 -6 months in case of late -stage 
complications".  Do they mean to say "to prevent late complications"?   
 
- Otherwise satisfactory.  
Tables:  
 
- Satisfactory.  
 
 
 
Figure:  
- Why did the authors only graph plastic stent data?  Also, should correct Y -axis label to 
"readmission".  
 
 
 
Are the methods approp riate 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 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 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 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, fees, funding, or salary from an  
organisation that may in any wa y 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 t he future?  
 
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 cont ent 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?  
 
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below. If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests  
 
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