Review for 10.1186/1471-230X-7-40 (2007)

Reviewer's report
Title:Meta-analyses of Fibrotest diagnostic value in chronic liver disease
Version: 2Date:17 August 2007
Reviewer: Claudio Tiribelli
Reviewer's report:
Reviewer's report: General
In this Ms Poynard and colleagues assess the validity of the Fibrotest (FT) they
have prposed in the recent past (2005) as a non invasive marker of fibrosis in
HCV patients . They extended the analysis in other non HCV subjects (liver
damage due to HBV, alcohol or fatty liver) and compared to what is believed the
golden standard, i.e. live biopsy. One additional issue addressed is if FT may be
good in assessing all the ranges of fibrosis and not only its absence or massive
presence. A total of 29 retrospective studies for a total of 6,378 cases were
analyzed and 3,282 subjects (50% of the cases enrolled) used for the evaluation.
The mean AUROC of liver disease of different etiology was similar and it did not
significantly differ in different stages of fibrosis. The author conclude that FT may
be an adequate test for a non invasive assessment of liver fibrosis.
Although the study is potentially important as adds information on a still debated
FT, the study has weaknesses that have to be considered before it could be
considered further.
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Major Compulsory Revisions (that the author must respond to before a decision
on publication can be reached)
The recruiting method of the sampling needs to be better specified. How was the
biopsy, performed in different places, assessed for reliability and comparability?
Was the length of the biopsy enough in all the 3,282 subjects used to compare
biopsy with FT? This information is crucial as it the reference endpoint to test FT.
What do the authors mean in saying (page 5, 3rd para) that the extraction of the
data was dome from the published studied “when possible”? How frequent was
this possible? The percentage of the major exclusion criteria in the 50% of cases
not examined needs to be reported. Again, more information appears adequate.
Expectedly, there is a rather large imbalance among the different classes of liver
disease where HCV accounts for more that 60% of the 5 categories. Was this
difference considered when statistical analysis was performed? Was this
relevant? Please define and explain.
The discussion needs to be trimmed and the tome made more dubitative.
Although the data show that FT may be indeed be a surrogate for liver biopsy,
caveats are still present and therefore the dogmatism has to be reduced.
It is surprising that the authors decided to publish the data in an open access
journal (which is good) when the FT is not freely available (which is less good). It
seems to me adequate to address this discrepancy in a note.
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Minor Essential Revisions (such as missing labels on figures, or the wrong use of
a term, which the author can be trusted to correct)
1. Fig 1A and !B are marked as Fig.1 and Fig. 2. Please fix.
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Discretionary Revisions (which the author can choose to ignore)
What next?: Revise and Review
Level of interest: An article of potentiasl interest
Quality of written English: Good
Statistical review: Yes but need to be seen by a statistician.
Declaration of competing interests: I declare that I have no competing interests.