Reviewer's report
Title:Psychological stress and coeliac disease in childhood: a cohort study
Version: 5Date:5 April 2010
Reviewer: Per Farup
Reviewer's report:
I do not have the previous version of the paper ahead of me, and do not find the
results I commented upon (95% CI for the ratio is 0.39 – 12.72) in the new
manuscript. The authors have probably performed new analyses.
I comment now only upon the OR and CI, Table 3 refers to a 95% CI 0.00-2.34.
An OR of 0 is nonsense. If you turn it around, the increased risk of CD in
non-exposed compared exposed, the OR is indefinite and the upper limit of the
95%CI is indefinite. This shows that the difference between non-exposed and
exposed might be enormous despite the fact that this study does not show a
significant difference.
Table 2 . Serious life event at age 1: Turn the table around and you see the
problem. The increased prevalence of CD in no serious life event compared with
a serious life event, OR = 2.22 with 95% CI 0.37 – 89.62. Your results show that
there might be a huge (enormous) difference in the prevalence between no
serious life event and a serious life event despite the fact that this study does not
show a significant difference.
It is correct that this study does not show a significant association between
psychological stress and CD, but does not exclude an enormous (indefinite)
association because of the small numbers of patients with CD. This has to be
discussed and mentioned also in the abstract.
This negative study is nearly valueless because it does not exclude an immense
effect of psychological stress on CD, and should not be published unless this is
made clear. Do the authors know what a type II error is? They mention that
“inappropriate reassurance to parents” is a type II error.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
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:Psychological stress and coeliac disease in childhood: a cohort study
Version: 5Date:5 April 2010
Reviewer: Per Farup
Reviewer's report:
I do not have the previous version of the paper ahead of me, and do not find the
results I commented upon (95% CI for the ratio is 0.39 – 12.72) in the new
manuscript. The authors have probably performed new analyses.
I comment now only upon the OR and CI, Table 3 refers to a 95% CI 0.00-2.34.
An OR of 0 is nonsense. If you turn it around, the increased risk of CD in
non-exposed compared exposed, the OR is indefinite and the upper limit of the
95%CI is indefinite. This shows that the difference between non-exposed and
exposed might be enormous despite the fact that this study does not show a
significant difference.
Table 2 . Serious life event at age 1: Turn the table around and you see the
problem. The increased prevalence of CD in no serious life event compared with
a serious life event, OR = 2.22 with 95% CI 0.37 – 89.62. Your results show that
there might be a huge (enormous) difference in the prevalence between no
serious life event and a serious life event despite the fact that this study does not
show a significant difference.
It is correct that this study does not show a significant association between
psychological stress and CD, but does not exclude an enormous (indefinite)
association because of the small numbers of patients with CD. This has to be
discussed and mentioned also in the abstract.
This negative study is nearly valueless because it does not exclude an immense
effect of psychological stress on CD, and should not be published unless this is
made clear. Do the authors know what a type II error is? They mention that
“inappropriate reassurance to parents” is a type II error.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
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:Psychological stress and coeliac disease in childhood: a cohort study
Version: 5Date:5 April 2010
Reviewer: Per Farup
Reviewer's report:
I do not have the previous version of the paper ahead of me, and do not find the
results I commented upon (95% CI for the ratio is 0.39 – 12.72) in the new
manuscript. The authors have probably performed new analyses.
I comment now only upon the OR and CI, Table 3 refers to a 95% CI 0.00-2.34.
An OR of 0 is nonsense. If you turn it around, the increased risk of CD in
non-exposed compared exposed, the OR is indefinite and the upper limit of the
95%CI is indefinite. This shows that the difference between non-exposed and
exposed might be enormous despite the fact that this study does not show a
significant difference.
Table 2 . Serious life event at age 1: Turn the table around and you see the
problem. The increased prevalence of CD in no serious life event compared with
a serious life event, OR = 2.22 with 95% CI 0.37 – 89.62. Your results show that
there might be a huge (enormous) difference in the prevalence between no
serious life event and a serious life event despite the fact that this study does not
show a significant difference.
It is correct that this study does not show a significant association between
psychological stress and CD, but does not exclude an enormous (indefinite)
association because of the small numbers of patients with CD. This has to be
discussed and mentioned also in the abstract.
This negative study is nearly valueless because it does not exclude an immense
effect of psychological stress on CD, and should not be published unless this is
made clear. Do the authors know what a type II error is? They mention that
“inappropriate reassurance to parents” is a type II error.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: Yes, and I have assessed the statistics in my report.
Declaration of competing interests:
I declare that I have no competing interests
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