Reviewer's report
Title:The Zelnorm Epidemiologic Study (ZEST): A Cohort Study Evaluating
Incidence of Abdominal and Pelvic Surgery related to Tegaserod Treatment
Version: 2Date:19 July 2012
Reviewer: Allen Brinker
Reviewer's report:
Major Compulsory Revisions
None
Minor Essential Revisions
None
Discretionary Revisions
Additional limitations needed - I believe the authors should offer further
discussion on the issue of misclassification afforded with selection of the
comparator arm of this and any observational study of IBS patients. As noted in
the literature (1,2), there appears to be substantial clinical heterogeneity of the
application of ICD codes within this population so as to make comparator cohorts
challenging. As noted by the authors in the Discussion and with interest in
patients with IBS, “gallbladder surgery may be used as part of a symptom
evaluation in some patients.” Unless an EMR / claims database can claim a
substantial portion of an adult’s life so as to capture gallbladder surgery in the
remote past, it may not be possible to derive a meaningful inference for incident
gall bladder surgery. Misclassification of this nature leads to the null – as was
reported for this study for gall badder surgery. Other outcomes – abdominal
surgeries in general – may not be differential and so may be better endpoints for
study other than gallbladder surgery.
1. Brinker A, Avigan M. Epidemiology of ischaemic colitis (letter). Aliment
Pharmacol Ther 2004;20(6):697-8.
2. Gallo-Torres H, Brinker A, Avigan M. Alosetron: ischemic colitis and serious
complications of constipation. Am J Gastroenterol 2006;101(5):1080-3.
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 have no financial interest in this work or subject area.
Reviewer's report
Title:The Zelnorm Epidemiologic Study (ZEST): A Cohort Study Evaluating
Incidence of Abdominal and Pelvic Surgery related to Tegaserod Treatment
Version: 2Date:19 July 2012
Reviewer: Allen Brinker
Reviewer's report:
Major Compulsory Revisions
None
Minor Essential Revisions
None
Discretionary Revisions
Additional limitations needed - I believe the authors should offer further
discussion on the issue of misclassification afforded with selection of the
comparator arm of this and any observational study of IBS patients. As noted in
the literature (1,2), there appears to be substantial clinical heterogeneity of the
application of ICD codes within this population so as to make comparator cohorts
challenging. As noted by the authors in the Discussion and with interest in
patients with IBS, “gallbladder surgery may be used as part of a symptom
evaluation in some patients.” Unless an EMR / claims database can claim a
substantial portion of an adult’s life so as to capture gallbladder surgery in the
remote past, it may not be possible to derive a meaningful inference for incident
gall bladder surgery. Misclassification of this nature leads to the null – as was
reported for this study for gall badder surgery. Other outcomes – abdominal
surgeries in general – may not be differential and so may be better endpoints for
study other than gallbladder surgery.
1. Brinker A, Avigan M. Epidemiology of ischaemic colitis (letter). Aliment
Pharmacol Ther 2004;20(6):697-8.
2. Gallo-Torres H, Brinker A, Avigan M. Alosetron: ischemic colitis and serious
complications of constipation. Am J Gastroenterol 2006;101(5):1080-3.
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 have no financial interest in this work or subject area.
Please review this paper.
user
Reviewer's report
Title:The Zelnorm Epidemiologic Study (ZEST): A Cohort Study Evaluating
Incidence of Abdominal and Pelvic Surgery related to Tegaserod Treatment
Version: 2Date:19 July 2012
Reviewer: Allen Brinker
Reviewer's report:
Major Compulsory Revisions
None
Minor Essential Revisions
None
Discretionary Revisions
Additional limitations needed - I believe the authors should offer further
discussion on the issue of misclassification afforded with selection of the
comparator arm of this and any observational study of IBS patients. As noted in
the literature (1,2), there appears to be substantial clinical heterogeneity of the
application of ICD codes within this population so as to make comparator cohorts
challenging. As noted by the authors in the Discussion and with interest in
patients with IBS, “gallbladder surgery may be used as part of a symptom
evaluation in some patients.” Unless an EMR / claims database can claim a
substantial portion of an adult’s life so as to capture gallbladder surgery in the
remote past, it may not be possible to derive a meaningful inference for incident
gall bladder surgery. Misclassification of this nature leads to the null – as was
reported for this study for gall badder surgery. Other outcomes – abdominal
surgeries in general – may not be differential and so may be better endpoints for
study other than gallbladder surgery.
1. Brinker A, Avigan M. Epidemiology of ischaemic colitis (letter). Aliment
Pharmacol Ther 2004;20(6):697-8.
2. Gallo-Torres H, Brinker A, Avigan M. Alosetron: ischemic colitis and serious
complications of constipation. Am J Gastroenterol 2006;101(5):1080-3.
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 have no financial interest in this work or subject area.
assistant