Review for 10.1186/1471-230X-8-13 (2008)

Reviewer's report
Title:Prevalence and determinants of biochemical dysfunction of the liver in
Atayal aboriginal community of Taiwan: Is betel nut chewing a risk factor?
Version: 1Date:15 July 2007
Reviewer: Eric M Yoshida
Reviewer's report:
General
This is an interesting paper that reports liver biochemical abnormalities as well as
ultrasound evidence of cirrhosis in a unique population (ie. an Aboriginal
population in Taiwan) and studies possible variables associated with the
abnormalities. Moreover, a unique consumed substance (ie. betal quid) is
specifically studied. An epidemiologic liver disease study in this Aboriginal
community of Taiwan is of great interest since little has been reported in the
North American literature on this population. Betel quid consumption as a
possible risk factor for liver disease is also noteworthy and important for
non-Taiwanese physicians to be aware of since this substance may be
consumed outside of Taiwan.
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Major Compulsory Revisions (that the author must respond to before a decision
on publication can be reached)
Although this is an interesting paper, there are areas of weakness/concern that
should be addressed by the investigators:
1. The authors should provide more descriptive and anthropologic background
information regarding the Aboriginal peoples of Taiwan in the Introduction. The
Aboriginal peoples of North America and Australia are, in general, very well
known but I doubt that many readers from outside of Taiwan are aware of this
population. For instance, a casual reader would want to know how this population
differs from the Taiwanese population in general (ie. is this population descended
from the Chinese? Is the population non-Chinese in anthropologic background
and more Polynesian? etc). Although there is a comment about differences in life
expectancy between the Taiwainese Aboriginals and non-Aboriginals, perhaps
some information about the social-economic background of this population would
be appropriate.
2. Betal quid consumption is little known in North America and the Introduction
should mention some basic information regarding betel quid - is it an illegal
contraband substance, why do people consume betel quid? What are the general
health-risks or benefits of betel quid? Is betel quid consumed with alcohol
(important since the authors report that betel quid appears to be a risk factor for
liver disease)? Does betel quid have an appetite stiumlating effect (ie. like
marijuana) or is it an appetite suppressant (ie. like coffee). This would be
interesting to know since increased BMI is also associated with liver biochemical
abnormalities (ie. NASH/NAFLD).
3. The investigators need to provide a better description of the studied
population. It is stated that the population studied is the "Atayla Aboriginal"
community yet the control population of non-Aboriginals also came from this
community (and their background should be better reported). The reason why
this community amongst the many Aboriginal groups (the authors report 12
Aboriginal groups in Taiwan) was studied should also be mentioned (ie. the
community was in the catchment area of the researchers, this community was
noted to have liver disease that attracted the interest of the investigators etc).
4. The investigators do not mention the dose of betel quid consumed or the
alcohol consumed. What constituted "heavy use" vs. occasional use. This is
important since there may be a dose-response effect with regards to hepatoxicity
of betel quid.
5. Were any other liver diseses screened for: ie. autoimmune hepatitis, primary
biliary cirrhosis etc.
6. Did any patients undergo liver biopsy? If so, what were the findings in the
patients with liver biochemical abnormalities?
7. The authors do not report the degree of liver biochemical abnormalities. It
appears that anyone who had a serum ALT greater than 37 units/L was
categorized as abnormal. The range of biochemical abnormalities should be
stated with a statification of the study population based on liver biochemical
abnormalities (ie. what proportion of the studied population had a serum ALT
5-10 times the upper limite of normal etc).
8. A diagnosis of cirrhosis was based on ultrasound findings. What were the
ultrasound features that the investigators used to make a diagnosis of cirrhosis?
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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. The statistical description in the methodology is weak. The authors should
state that a chi square test was used in the univariate analysis and that the
multivariate analysis consisted of multiple logistic regression. This is stated in the
tables or the Result section but not in the methodology. Also, was a forwards or
backwards stepwise multiple logistic regression method used? How were the
variables for the multi-variate analysis chosen? (ie. univariate p value of .05, 0.10
etc).
2. Did the study undergo review by the local research ethics review board? This
should be stated.
3. Where did the funding for this study come from?
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Discretionary Revisions (which the author can choose to ignore)
What next?: Unable to decide on acceptance or rejection until the authors have
responded to the major compulsory revisions
Level of interest: An article of importance in its field
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I have no competing interests