Review for 10.1186/1471-230X-12-60 (2012)

Reviewer's report
Title:The Gastrointestinal Electrical Mapping Suite (GEMS): Software for
analyzing and visualizing gastrointestinal multi-electrode recordings
Version: 2Date:6 January 2012
Reviewer: Gloria Millaray Curilem
Reviewer's report:
- Major Compulsory Revisions
The paper describes GEMS, a general purpose software for the analysis of
gastrointestinal high resolution electrical signals. It performs a quantitative
analysis of multichannel electrogastrograms (EGG). It includes techniques to
depurate the signals (preprocessing) and tools to automatically detect events
(processing) in the time domain. Its most powerful innovation is a graphical
interface that allows, according to the authors, an intuitive interaction with the
user and a graphical representation of the detection processes. The proposed
system is intended to support visualization of the multi electrode recordings to
facilitate the analysis and comprehension of gastrointestinal electrical disorders.
The paper presents a software package, emphasizing the facilities supplied and
their implementation. The paper does not present new findings in the processing
techniques of gastrointestinal electrical signals, but integrates many new EGG
processing techniques, described in other publications thus it supplies new tools
to facilitate the processing of the EGG signals and its visualization. The
commercial electrogastrographs includes software allowing basic processing of
the signals. As far as I know, the analysis tools incorporated in GEMS are novel,
like for example the automatic event recognition. This is why in my opinion the
proposed software addresses novel tasks.
The paper is clear and well structured. The manuscript describes the facilities
supplied by the software and exposes briefly how to manage them. The
manuscript states clearly the software requirements and the different formats
accepted for the input and output of the signals. The authors discuss the
advantages and limitations of the proposed system and present the main issues
that lead to future improvements. The system is available on-line by filling out
and sending a form.
There are some issues that need to be addressed for the publication of this
paper. One of my questionings is to whom is the software addressed? The GUI
allows the setting of many parameters, like filtering methods, falling edge, etc.
that I think are not addressed to the medical team and then who is the final user?
The software performs time-domain analysis, no tools for analyzing the records
in the frequency or in the estimation of the probability distribution are supplied.
Today there is almost a consensus that biomedical signal analysis should include
three domains: temporal, frequency and probability. In particular, the bibliography
of gastrointestinal electrical signal processing shows that the frequency analysis
is one of its most important tools. Why didn’t the software include other domains?
The problem the software is designed to address is explained in a general way.
The paper does not explain for what kind of specific analysis this system may be
a contribution and to what extent the software is successful in satisfying these
specific problem requirements. Thus the authors do not demonstrate the
usefulness of the tool. How were the facilities proposed in the system evaluated
and validated by the specialists in electrogastrography. Were the processing
tools and the graphical representation a contribution for the medical experts? The
graphical mapping of the electrical signals is useful in other fields, like cardiology,
but in the gastrointestinal field, does this kind of representation give significant
and reliable information?
The software needs a validation process. It should be validated quantitatively
from its implementation point of view and qualitatively from the point of view of its
medical contribution. It would be interesting that the article presents examples of
diseases or dysfunctions where the system has been successfully applied. If this
is not included, this article becomes a simple description of algorithms to process
multiple time signals recordings. The paper should emphasize why it is stated in
the discussion that “GEMS is already proving to be of great value…”. In my
opinion, this information cannot be only referenced; it should be explicit in the
paper.
- Minor Essential Revisions
Background, last line of the second paragraph: “is now now progressing” it
should say: “is now progressing”.
Parameters file, forth line of the first paragraph: “(REGOUPS) algorithm tuning
options” it should say: “(REGOUPS), algorithm tuning options”.
Activation time detection, 8th and 9th lines of the first paragraph: “crosses the
(time varying) threshold” it should say: “crosses the time varying threshold”
The references of the figures in the text do not correspond to the figures supplied
numbers. The references were confusing.
- Discretionary Revisions
I suggest including in the title the fact that GEMS offers a time-domain analysis of
the gastrointestinal signals.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
'I declare that I have no competing interests'