Review for 10.1186/1471-230X-8-11 (2008)

Reviewer's report
Title:Effects of Pectin Liquid on Gastroesophageal Reflux Disease in Children
With Cerebral Palsy
Version: 2Date:2 January 2008
Reviewer: Tobias G Wenzl
Reviewer's report:
Comments
This is a study on the effect of two different concentrations of pectin in liquid
formula on acid exposure and symptoms attributed to GER in children with CP.
The authors suggest pectin as a management alternative for GERD in this group
of patients.
Abstract
- "Changing feeding style" (please define) is not an "alternative" therapy but part
of the standard approach.
- which "symptoms" ? (please define)
- the effect of thickeners on GER has been investigated before.
- when was the 48 hour pH measurement performed ?
- how was the relation of GER and symptoms established ?
- how where the symptoms recorded ?
- which "cough-score" was used ?
Background
- "Changing feeding style" (please define) is not an "alternative" therapy but part
of the standard approach.
- The authors describe thickeners as effective in decreasing GER, but cite a
study that demonstrated lack of efficacy (18) ? Reference "(7-9)" should probably
read "(17-19)" ?
Methods
- how was the diagnosis "dyspnea or laryngeal edema due to GERD" established
?
- how were the "GER-related symptoms" established ?
- how was GER "considered as a major contributing factor" to recurrent
pneumonia ?
- was the pectin really injected "forcefully" ?
- when was the 48 hour pH measurement performed. ?
- how was the correct postion of the catheter confirmed ?
- how were the symptoms recorded ?
- which "scoring system" was used for cough or wheeze ?
Results
- although statistically significant, it seems remarkable that almost no patient
reached a normal Reflux-Index after pectin containing diet (Fig. 1A). Please
comment.
- how was "vomiting associated with cough" defined ?
- which "cough-score" was used ?
- recording of "frequency of using oxygen" not mentioned in Methods.
- recording of "fever or bradycardia" not mentioned in Methods.
Discussion
- how was the GER-symptom association established ?
- the authors mention that their unexplained decrease of GER associated
symptoms may be due to their lack of recording weakly and non-acid reflux. It
has been generally accepted, that using pH monitoring alone is not the right
method for this kind of study. Please comment.
- using residual gastric contents is not the best method to measure gastric
emptying.
- the authors discuss their concern about the significant increase of viscosity in
the mixture they use. However, they then recommend to use even "much higher
concentrations of pectin". This needs to be discussed.
- as the method of recording symptoms and the method of defining them as
being GER-related is not decribed, the conclusion "pectin liquid might improve
GER-related symptoms" cannot be made from the data presented.
Table 2
- what does "/w" mean ?
On balance, one must recommend to ask the authors for "Major Compulsory
Revisions" in their manuscript before a decison about acceptance for publication
can be made, i.e. "Unable to decide" at this stage.
The category for the manuscript as it stands now is "article of limited interest".
The English language "needs some corrections before being published".
No further statistical advice must be seeked.
I declare that I have no competing interests.