Reviewer's report
Title:Management of Irritable Bowel Syndrome in Primary Care: An Exploratory
Randomised Controlled Trial of Mebeverine, Methylcellulose, Placebo and a
Self-management website.
Version: 2Date:21 December 2012
Reviewer: Per G Farup
Reviewer's report:
The paper reports the results of a placebo controlled RCT with factorial design
comparing common drug therapies and web-based self-management treatment.
The idea and the design (factorial design) are brilliant for testing independent
treatment alternatives. The paper has some major weaknesses:
• What were the aims? According to the protocol (published in BMC
Gastroenterology 2010; 10: 136) and the paper, there were two primary aims
(IBS SSS and IBS QoL). I prefer one primary aim. According to the registration in
ClinicalTrials.gov there was only one primary aim (IBS SSS). Why has the
primary aim been changed? ClincicalTrials.gov refers to IBS QoL as a secondary
aim. The protocol and the paper refer to several secondary aims, none of them
have been mentioned in ClinicalTrials.gov.
• My main objection is the conclusion of the paper both in the abstract and the
paper. The correct conclusion is that none of the interventions had a significant
effect. I prefer a presentation of the differences in IBS-SSS (the primary aim)
between the treatment modalities with confidence intervals. Could a clinically
significant difference have been missed (type II error)?
• The discussion should focus on the fact that no significant effect was shown,
and in addition mention the finding related to the secondary aims which are
usable primarily for generating new hypotheses. Is it worth performing a new trial
to show an effect on SGA (dichotomized – see below) when IBS SSS and IBS
QoL remained unchanged?
• Some questions about the statistics. SGA is a 5 point scale, why was it
dichtomized? HAD anxiety and HAD depression were handled differently. Why
was HAD anxiety used as a continuous scale (with mean values) and HAD
depression (and Enablement score) as grouped (ordered) variable? According to
the paper ITT analyses were performed, but there is no information about the
method used to handle missing data. Was “last observation carried forward” or
“imputation of missing data etc… used”
• The trial is mentioned as an explorative study. Was it an explorative study when
the aim was to test a specified hypothesis?
• The main finding according to the discussion was that it was feasible to recruit
patients and perform this trial (not very interesting). If screening of 5700 patients
was necessary to include 135 patients, the external validity of the study is
questionable.
• I have not mentioned my minor concerns.
Level of interest: An article of importance in its field
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:Management of Irritable Bowel Syndrome in Primary Care: An Exploratory
Randomised Controlled Trial of Mebeverine, Methylcellulose, Placebo and a
Self-management website.
Version: 2Date:21 December 2012
Reviewer: Per G Farup
Reviewer's report:
The paper reports the results of a placebo controlled RCT with factorial design
comparing common drug therapies and web-based self-management treatment.
The idea and the design (factorial design) are brilliant for testing independent
treatment alternatives. The paper has some major weaknesses:
• What were the aims? According to the protocol (published in BMC
Gastroenterology 2010; 10: 136) and the paper, there were two primary aims
(IBS SSS and IBS QoL). I prefer one primary aim. According to the registration in
ClinicalTrials.gov there was only one primary aim (IBS SSS). Why has the
primary aim been changed? ClincicalTrials.gov refers to IBS QoL as a secondary
aim. The protocol and the paper refer to several secondary aims, none of them
have been mentioned in ClinicalTrials.gov.
• My main objection is the conclusion of the paper both in the abstract and the
paper. The correct conclusion is that none of the interventions had a significant
effect. I prefer a presentation of the differences in IBS-SSS (the primary aim)
between the treatment modalities with confidence intervals. Could a clinically
significant difference have been missed (type II error)?
• The discussion should focus on the fact that no significant effect was shown,
and in addition mention the finding related to the secondary aims which are
usable primarily for generating new hypotheses. Is it worth performing a new trial
to show an effect on SGA (dichotomized – see below) when IBS SSS and IBS
QoL remained unchanged?
• Some questions about the statistics. SGA is a 5 point scale, why was it
dichtomized? HAD anxiety and HAD depression were handled differently. Why
was HAD anxiety used as a continuous scale (with mean values) and HAD
depression (and Enablement score) as grouped (ordered) variable? According to
the paper ITT analyses were performed, but there is no information about the
method used to handle missing data. Was “last observation carried forward” or
“imputation of missing data etc… used”
• The trial is mentioned as an explorative study. Was it an explorative study when
the aim was to test a specified hypothesis?
• The main finding according to the discussion was that it was feasible to recruit
patients and perform this trial (not very interesting). If screening of 5700 patients
was necessary to include 135 patients, the external validity of the study is
questionable.
• I have not mentioned my minor concerns.
Level of interest: An article of importance in its field
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:Management of Irritable Bowel Syndrome in Primary Care: An Exploratory
Randomised Controlled Trial of Mebeverine, Methylcellulose, Placebo and a
Self-management website.
Version: 2Date:21 December 2012
Reviewer: Per G Farup
Reviewer's report:
The paper reports the results of a placebo controlled RCT with factorial design
comparing common drug therapies and web-based self-management treatment.
The idea and the design (factorial design) are brilliant for testing independent
treatment alternatives. The paper has some major weaknesses:
• What were the aims? According to the protocol (published in BMC
Gastroenterology 2010; 10: 136) and the paper, there were two primary aims
(IBS SSS and IBS QoL). I prefer one primary aim. According to the registration in
ClinicalTrials.gov there was only one primary aim (IBS SSS). Why has the
primary aim been changed? ClincicalTrials.gov refers to IBS QoL as a secondary
aim. The protocol and the paper refer to several secondary aims, none of them
have been mentioned in ClinicalTrials.gov.
• My main objection is the conclusion of the paper both in the abstract and the
paper. The correct conclusion is that none of the interventions had a significant
effect. I prefer a presentation of the differences in IBS-SSS (the primary aim)
between the treatment modalities with confidence intervals. Could a clinically
significant difference have been missed (type II error)?
• The discussion should focus on the fact that no significant effect was shown,
and in addition mention the finding related to the secondary aims which are
usable primarily for generating new hypotheses. Is it worth performing a new trial
to show an effect on SGA (dichotomized – see below) when IBS SSS and IBS
QoL remained unchanged?
• Some questions about the statistics. SGA is a 5 point scale, why was it
dichtomized? HAD anxiety and HAD depression were handled differently. Why
was HAD anxiety used as a continuous scale (with mean values) and HAD
depression (and Enablement score) as grouped (ordered) variable? According to
the paper ITT analyses were performed, but there is no information about the
method used to handle missing data. Was “last observation carried forward” or
“imputation of missing data etc… used”
• The trial is mentioned as an explorative study. Was it an explorative study when
the aim was to test a specified hypothesis?
• The main finding according to the discussion was that it was feasible to recruit
patients and perform this trial (not very interesting). If screening of 5700 patients
was necessary to include 135 patients, the external validity of the study is
questionable.
• I have not mentioned my minor concerns.
Level of interest: An article of importance in its field
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
assistant