Reviewer's report
Title:How does comorbidity affect cost of health care in patients with irritable
bowel syndrome? A cohort study in general practice
Version: 1Date:1 January 2010
Reviewer: George Longstreth
Reviewer's report:
The authors thoroughly studied the health care costs in 164 general practice
(GP) patients with IBS. The study is potentially important, as IBS is very
common, and the report has novelty because of its focus on GP patients. The
findings supplement other reports of the prominence of non-gastrointestinal
symptoms and associated costs in patients with IBS.
Major Compulsory Revisions
1) I am concerned about the possibility of enrichment of the study group with
patients whose costs were high. Authors report that there were 830 consecutive
GP patients with IBS defined by Rome II criteria, yet the GPs entered only 208
into the study after agreeing with the diagnosis. Authors should report exactly
what the GPs were told about the study; in particular, were they told that the
study would focus on health care costs, especially non-IBS costs? It seems
unlikely that ¾ of the patients with Rome II-positive IBS did not actually have IBS,
and authors should discuss the possibility that many of them had lower costs
than the included patients. Authors should also report what the study nurses
knew about the planned analysis, as they could have been biased in their data
collection. Specifically, did they know that non-IBS costs would be compared with
IBS costs?
2) The failure to find an association between costs and severity of IBS conflicts
with previous findings; for example the uncited publication: Longstreth GF, et al.
Am J Gastroenterol 2003;98:600-607. That article reported an association
between severity of abdominal pain/discomfort and costs in 558 subjects with
IBS. Authors should comment on the possibility that their method of measuring
severity underlies this finding. They should also comment on whether the number
of cases was too small to detect an association of severity with cost.
3) Finally, authors should provide further information on their regression analysis.
Specifically, were their more than 10 events per variable, as is recommended?
Level of interest: An article of limited interest
Quality of written English: Acceptable
Statistical review: Yes, but I do not feel adequately qualified to assess the
statistics.
Declaration of competing interests:
I declare that I have no competing interests.
Reviewer's report
Title:How does comorbidity affect cost of health care in patients with irritable
bowel syndrome? A cohort study in general practice
Version: 1Date:1 January 2010
Reviewer: George Longstreth
Reviewer's report:
The authors thoroughly studied the health care costs in 164 general practice
(GP) patients with IBS. The study is potentially important, as IBS is very
common, and the report has novelty because of its focus on GP patients. The
findings supplement other reports of the prominence of non-gastrointestinal
symptoms and associated costs in patients with IBS.
Major Compulsory Revisions
1) I am concerned about the possibility of enrichment of the study group with
patients whose costs were high. Authors report that there were 830 consecutive
GP patients with IBS defined by Rome II criteria, yet the GPs entered only 208
into the study after agreeing with the diagnosis. Authors should report exactly
what the GPs were told about the study; in particular, were they told that the
study would focus on health care costs, especially non-IBS costs? It seems
unlikely that ¾ of the patients with Rome II-positive IBS did not actually have IBS,
and authors should discuss the possibility that many of them had lower costs
than the included patients. Authors should also report what the study nurses
knew about the planned analysis, as they could have been biased in their data
collection. Specifically, did they know that non-IBS costs would be compared with
IBS costs?
2) The failure to find an association between costs and severity of IBS conflicts
with previous findings; for example the uncited publication: Longstreth GF, et al.
Am J Gastroenterol 2003;98:600-607. That article reported an association
between severity of abdominal pain/discomfort and costs in 558 subjects with
IBS. Authors should comment on the possibility that their method of measuring
severity underlies this finding. They should also comment on whether the number
of cases was too small to detect an association of severity with cost.
3) Finally, authors should provide further information on their regression analysis.
Specifically, were their more than 10 events per variable, as is recommended?
Level of interest: An article of limited interest
Quality of written English: Acceptable
Statistical review: Yes, but I do not feel adequately qualified to assess the
statistics.
Declaration of competing interests:
I declare that I have no competing interests.
Please review this paper.
user
Reviewer's report
Title:How does comorbidity affect cost of health care in patients with irritable
bowel syndrome? A cohort study in general practice
Version: 1Date:1 January 2010
Reviewer: George Longstreth
Reviewer's report:
The authors thoroughly studied the health care costs in 164 general practice
(GP) patients with IBS. The study is potentially important, as IBS is very
common, and the report has novelty because of its focus on GP patients. The
findings supplement other reports of the prominence of non-gastrointestinal
symptoms and associated costs in patients with IBS.
Major Compulsory Revisions
1) I am concerned about the possibility of enrichment of the study group with
patients whose costs were high. Authors report that there were 830 consecutive
GP patients with IBS defined by Rome II criteria, yet the GPs entered only 208
into the study after agreeing with the diagnosis. Authors should report exactly
what the GPs were told about the study; in particular, were they told that the
study would focus on health care costs, especially non-IBS costs? It seems
unlikely that ¾ of the patients with Rome II-positive IBS did not actually have IBS,
and authors should discuss the possibility that many of them had lower costs
than the included patients. Authors should also report what the study nurses
knew about the planned analysis, as they could have been biased in their data
collection. Specifically, did they know that non-IBS costs would be compared with
IBS costs?
2) The failure to find an association between costs and severity of IBS conflicts
with previous findings; for example the uncited publication: Longstreth GF, et al.
Am J Gastroenterol 2003;98:600-607. That article reported an association
between severity of abdominal pain/discomfort and costs in 558 subjects with
IBS. Authors should comment on the possibility that their method of measuring
severity underlies this finding. They should also comment on whether the number
of cases was too small to detect an association of severity with cost.
3) Finally, authors should provide further information on their regression analysis.
Specifically, were their more than 10 events per variable, as is recommended?
Level of interest: An article of limited interest
Quality of written English: Acceptable
Statistical review: Yes, but I do not feel adequately qualified to assess the
statistics.
Declaration of competing interests:
I declare that I have no competing interests.
assistant