Reviewer's report
Title:To compare the effect of two Zhizhu pills in the treat- ment of functional
dyspepsia of spleen-deficiency and qi-stagnation syndromea randomized ,
double- blinded multicenter and group sequential study design
Version: 1Date:27 October 2010
Reviewer: Carl J Lombard
Reviewer's report:
Major
The purpose of this paper is not clear to me. I am not sure if this paper is about
reporting the results of the trial or whether it is an example of a comparative trial
with a particular type of stopping boundary.
If it is the first then I have problem with the reporting of the results of the trial
since no effect size of confidence interval is reported. The pre-post distribution of
the symptom score is not given by group.
If it is the second option one would expect a much more detailed expose of why
the whitehead design was used and not any of the other group sequential design
even those of whitehead in 2001 for example. This outline would be of benefit to
the reader. Showing the calculation of the effect size and confidence intervals
using the stopped trial will also be useful in 'this' type of paper.
At the moment this paper is neither of the cases outlined above.
What was the basis for assumming that the one product will have a superiority of
15%? Why was equivalence not considered?
From checking the details on the stopping boundaries given in the analysis
section I could deduce that the metric of comparison was the log odds ratio and
that theta 1 given in this section is the value of this statistics under H1. These
descriptive details are missing. In the Results section under TT the test statistic
referred to is a log- rank statistic which is incorrect
Table 1
The presentation of the descriptive statistics in this table is not good.
What are the statistics - mean, median, standard deviation? Why brackets in the
one group and +_ in the other? The main critique is that of presenting p-values
for the baseline comparisons. Why is this done - was the randomisation flawed?
Please drop the column of p-value in this table
Results table - no sure why no estimated effects within and between groups are
presented with the necessary confidence intervals taking the interim monitoring
into account?
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: Yes, and I have assessed the statistics in my report.
Declaration of competing interests:
'I declare that I have no competing interests'
Reviewer's report
Title:To compare the effect of two Zhizhu pills in the treat- ment of functional
dyspepsia of spleen-deficiency and qi-stagnation syndromea randomized ,
double- blinded multicenter and group sequential study design
Version: 1Date:27 October 2010
Reviewer: Carl J Lombard
Reviewer's report:
Major
The purpose of this paper is not clear to me. I am not sure if this paper is about
reporting the results of the trial or whether it is an example of a comparative trial
with a particular type of stopping boundary.
If it is the first then I have problem with the reporting of the results of the trial
since no effect size of confidence interval is reported. The pre-post distribution of
the symptom score is not given by group.
If it is the second option one would expect a much more detailed expose of why
the whitehead design was used and not any of the other group sequential design
even those of whitehead in 2001 for example. This outline would be of benefit to
the reader. Showing the calculation of the effect size and confidence intervals
using the stopped trial will also be useful in 'this' type of paper.
At the moment this paper is neither of the cases outlined above.
What was the basis for assumming that the one product will have a superiority of
15%? Why was equivalence not considered?
From checking the details on the stopping boundaries given in the analysis
section I could deduce that the metric of comparison was the log odds ratio and
that theta 1 given in this section is the value of this statistics under H1. These
descriptive details are missing. In the Results section under TT the test statistic
referred to is a log- rank statistic which is incorrect
Table 1
The presentation of the descriptive statistics in this table is not good.
What are the statistics - mean, median, standard deviation? Why brackets in the
one group and +_ in the other? The main critique is that of presenting p-values
for the baseline comparisons. Why is this done - was the randomisation flawed?
Please drop the column of p-value in this table
Results table - no sure why no estimated effects within and between groups are
presented with the necessary confidence intervals taking the interim monitoring
into account?
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: Yes, and I have assessed the statistics in my report.
Declaration of competing interests:
'I declare that I have no competing interests'
Please review this paper.
user
Reviewer's report
Title:To compare the effect of two Zhizhu pills in the treat- ment of functional
dyspepsia of spleen-deficiency and qi-stagnation syndromea randomized ,
double- blinded multicenter and group sequential study design
Version: 1Date:27 October 2010
Reviewer: Carl J Lombard
Reviewer's report:
Major
The purpose of this paper is not clear to me. I am not sure if this paper is about
reporting the results of the trial or whether it is an example of a comparative trial
with a particular type of stopping boundary.
If it is the first then I have problem with the reporting of the results of the trial
since no effect size of confidence interval is reported. The pre-post distribution of
the symptom score is not given by group.
If it is the second option one would expect a much more detailed expose of why
the whitehead design was used and not any of the other group sequential design
even those of whitehead in 2001 for example. This outline would be of benefit to
the reader. Showing the calculation of the effect size and confidence intervals
using the stopped trial will also be useful in 'this' type of paper.
At the moment this paper is neither of the cases outlined above.
What was the basis for assumming that the one product will have a superiority of
15%? Why was equivalence not considered?
From checking the details on the stopping boundaries given in the analysis
section I could deduce that the metric of comparison was the log odds ratio and
that theta 1 given in this section is the value of this statistics under H1. These
descriptive details are missing. In the Results section under TT the test statistic
referred to is a log- rank statistic which is incorrect
Table 1
The presentation of the descriptive statistics in this table is not good.
What are the statistics - mean, median, standard deviation? Why brackets in the
one group and +_ in the other? The main critique is that of presenting p-values
for the baseline comparisons. Why is this done - was the randomisation flawed?
Please drop the column of p-value in this table
Results table - no sure why no estimated effects within and between groups are
presented with the necessary confidence intervals taking the interim monitoring
into account?
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: Yes, and I have assessed the statistics in my report.
Declaration of competing interests:
'I declare that I have no competing interests'
assistant