Reviewer's report
Title:Nine-year incident diabetes is predicted by fatty liver indices: The French
D.E.S.I.R. study
Version: 1Date:14 March 2010
Reviewer: Janus Ong
Reviewer's report:
I. Major Compulsory Revisions
1. The indices used in this study still require validation in populations outside of
the populations that they were developed from. In addition, the performance
characteristics of the indices, the Fatty Liver Index in particular, leave room for
misclassification considering a positive likelihood ratio of only 4.2 for predicting
fatty liver.
2. The original reports for the two indices suggest cut-off scores for the diagnosis
of fatty liver disease - a FLI >/= 60 and a NAFLD-FLS > -0.640. It is thus the
understanding of this reviewer that the question the study wanted to answer was
whether NAFLD as diagnosed using the two indices would be predictive of
incident diabetes. An affirmative answer to this research question would be
clinically relevant as screening for diabetes might be advocated in patients
diagnosed with NAFLD. The analysis that would have been ideal would have
been to divide the patients into those with NAFLD and those without NAFLD
based on the cut-offs for both the FLI and the NAFLD-FLS. The two groups
would then be compared as to the development of incident diabetes. I would
submit that the results of the current analyses using quartiles are not at all
surprising as these indices contain known predictors of incident diabetes such as
triglycerides, BMI, and waist circumference for FLI and metabolic syndrome for
NAFLD-FLS. In fact, results to the contrary would be difficult to explain.
3. In the calculation of the odds ratios for incident diabetes, it would be expected
in the multivariate analysis that potential confounders of the association between
the indices and incident diabetes be adjusted for. Table 1 shows in addition to
the adjustment factors shown in Table 2, variables such as BMI, waist
circumference, cholesterol levels were correlated with the FLI and thus should be
included as adjustment factors.
II. Minor Essential Revisions
1. Biochemical measurements were conducted in several sites using different
equipment. Are the results from these different sites comparable?
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
Reviewer's report
Title:Nine-year incident diabetes is predicted by fatty liver indices: The French
D.E.S.I.R. study
Version: 1Date:14 March 2010
Reviewer: Janus Ong
Reviewer's report:
I. Major Compulsory Revisions
1. The indices used in this study still require validation in populations outside of
the populations that they were developed from. In addition, the performance
characteristics of the indices, the Fatty Liver Index in particular, leave room for
misclassification considering a positive likelihood ratio of only 4.2 for predicting
fatty liver.
2. The original reports for the two indices suggest cut-off scores for the diagnosis
of fatty liver disease - a FLI >/= 60 and a NAFLD-FLS > -0.640. It is thus the
understanding of this reviewer that the question the study wanted to answer was
whether NAFLD as diagnosed using the two indices would be predictive of
incident diabetes. An affirmative answer to this research question would be
clinically relevant as screening for diabetes might be advocated in patients
diagnosed with NAFLD. The analysis that would have been ideal would have
been to divide the patients into those with NAFLD and those without NAFLD
based on the cut-offs for both the FLI and the NAFLD-FLS. The two groups
would then be compared as to the development of incident diabetes. I would
submit that the results of the current analyses using quartiles are not at all
surprising as these indices contain known predictors of incident diabetes such as
triglycerides, BMI, and waist circumference for FLI and metabolic syndrome for
NAFLD-FLS. In fact, results to the contrary would be difficult to explain.
3. In the calculation of the odds ratios for incident diabetes, it would be expected
in the multivariate analysis that potential confounders of the association between
the indices and incident diabetes be adjusted for. Table 1 shows in addition to
the adjustment factors shown in Table 2, variables such as BMI, waist
circumference, cholesterol levels were correlated with the FLI and thus should be
included as adjustment factors.
II. Minor Essential Revisions
1. Biochemical measurements were conducted in several sites using different
equipment. Are the results from these different sites comparable?
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
Please review this paper.
user
Reviewer's report
Title:Nine-year incident diabetes is predicted by fatty liver indices: The French
D.E.S.I.R. study
Version: 1Date:14 March 2010
Reviewer: Janus Ong
Reviewer's report:
I. Major Compulsory Revisions
1. The indices used in this study still require validation in populations outside of
the populations that they were developed from. In addition, the performance
characteristics of the indices, the Fatty Liver Index in particular, leave room for
misclassification considering a positive likelihood ratio of only 4.2 for predicting
fatty liver.
2. The original reports for the two indices suggest cut-off scores for the diagnosis
of fatty liver disease - a FLI >/= 60 and a NAFLD-FLS > -0.640. It is thus the
understanding of this reviewer that the question the study wanted to answer was
whether NAFLD as diagnosed using the two indices would be predictive of
incident diabetes. An affirmative answer to this research question would be
clinically relevant as screening for diabetes might be advocated in patients
diagnosed with NAFLD. The analysis that would have been ideal would have
been to divide the patients into those with NAFLD and those without NAFLD
based on the cut-offs for both the FLI and the NAFLD-FLS. The two groups
would then be compared as to the development of incident diabetes. I would
submit that the results of the current analyses using quartiles are not at all
surprising as these indices contain known predictors of incident diabetes such as
triglycerides, BMI, and waist circumference for FLI and metabolic syndrome for
NAFLD-FLS. In fact, results to the contrary would be difficult to explain.
3. In the calculation of the odds ratios for incident diabetes, it would be expected
in the multivariate analysis that potential confounders of the association between
the indices and incident diabetes be adjusted for. Table 1 shows in addition to
the adjustment factors shown in Table 2, variables such as BMI, waist
circumference, cholesterol levels were correlated with the FLI and thus should be
included as adjustment factors.
II. Minor Essential Revisions
1. Biochemical measurements were conducted in several sites using different
equipment. Are the results from these different sites comparable?
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
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