Reviewer's report
Title:Endoscopic diagnosis of early gastric cancer and precancerous lesion
Version: 1Date:7 October 2011
Reviewer: Philip Le Page
Reviewer's report:
Major Comulsory revisions:
- The Method does not address the Aim of the study. The Aim is stated to
"compare the accuracy and sensitivity of magnifying chromoendoscopy, NBI with
conventional endoscopy for diagnosis of precancerous lesions and early gastric
cancer". The Method is for the observers the subjectively score the image
qualities. A Poor or a Good Image quality does not mean the "accuracy or
sensitivity is different". In fact no Data is given on these 2 findings. In this study it
appears all methods, included conventioanl endoscopy, had 100% sensitivity! (as
only those with confirmed lesions on histo were included). So the Method does
not address the Aim and hence detracts from the validity of the Results.
- The only conclusions of the results from the utilised method are that the image
quality is superior for the 2 new technologies. Yet Observer bias in the discussion
is not noted, and should be discussed as a source of bias....One may extrapolate
that these new technologies may improve sensitivity and accuracy, but there is
no evidence in their scientific data for that here.
- The numbers are also inconsistent. The abstract states 142 patients but the
Body states 122 patients.
- A flow chart would be useful here to show what actually happened. It appears
Included patients were those that already had conventional then NBI/Mag
imaging and HAD Histo confirming a lesion. But were there patients that had a
lesion on conventional endoscopy but not on the other 2 methods and no lesion
found on histo??? If so this would address accuracy issues. Also, categorically
did these patients not have any biospies after their inital endoscopy finding a
lesion?
Minor Essential Revisions:
- Labelling on figure 1 - Photos not marked A/B/C/D
- Abstract states is retropective study but main body states is prospective study
(again in Background of main body states is retrospective). This needs to be
clarified.
Discretionary Revisions:
- They could talk about potential problems of over sensitivity (Reduced
specificity)
Level of interest: An article of importance in its field
Quality of written English: Needs some language corrections before being
published
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:Endoscopic diagnosis of early gastric cancer and precancerous lesion
Version: 1Date:7 October 2011
Reviewer: Philip Le Page
Reviewer's report:
Major Comulsory revisions:
- The Method does not address the Aim of the study. The Aim is stated to
"compare the accuracy and sensitivity of magnifying chromoendoscopy, NBI with
conventional endoscopy for diagnosis of precancerous lesions and early gastric
cancer". The Method is for the observers the subjectively score the image
qualities. A Poor or a Good Image quality does not mean the "accuracy or
sensitivity is different". In fact no Data is given on these 2 findings. In this study it
appears all methods, included conventioanl endoscopy, had 100% sensitivity! (as
only those with confirmed lesions on histo were included). So the Method does
not address the Aim and hence detracts from the validity of the Results.
- The only conclusions of the results from the utilised method are that the image
quality is superior for the 2 new technologies. Yet Observer bias in the discussion
is not noted, and should be discussed as a source of bias....One may extrapolate
that these new technologies may improve sensitivity and accuracy, but there is
no evidence in their scientific data for that here.
- The numbers are also inconsistent. The abstract states 142 patients but the
Body states 122 patients.
- A flow chart would be useful here to show what actually happened. It appears
Included patients were those that already had conventional then NBI/Mag
imaging and HAD Histo confirming a lesion. But were there patients that had a
lesion on conventional endoscopy but not on the other 2 methods and no lesion
found on histo??? If so this would address accuracy issues. Also, categorically
did these patients not have any biospies after their inital endoscopy finding a
lesion?
Minor Essential Revisions:
- Labelling on figure 1 - Photos not marked A/B/C/D
- Abstract states is retropective study but main body states is prospective study
(again in Background of main body states is retrospective). This needs to be
clarified.
Discretionary Revisions:
- They could talk about potential problems of over sensitivity (Reduced
specificity)
Level of interest: An article of importance in its field
Quality of written English: Needs some language corrections before being
published
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:Endoscopic diagnosis of early gastric cancer and precancerous lesion
Version: 1Date:7 October 2011
Reviewer: Philip Le Page
Reviewer's report:
Major Comulsory revisions:
- The Method does not address the Aim of the study. The Aim is stated to
"compare the accuracy and sensitivity of magnifying chromoendoscopy, NBI with
conventional endoscopy for diagnosis of precancerous lesions and early gastric
cancer". The Method is for the observers the subjectively score the image
qualities. A Poor or a Good Image quality does not mean the "accuracy or
sensitivity is different". In fact no Data is given on these 2 findings. In this study it
appears all methods, included conventioanl endoscopy, had 100% sensitivity! (as
only those with confirmed lesions on histo were included). So the Method does
not address the Aim and hence detracts from the validity of the Results.
- The only conclusions of the results from the utilised method are that the image
quality is superior for the 2 new technologies. Yet Observer bias in the discussion
is not noted, and should be discussed as a source of bias....One may extrapolate
that these new technologies may improve sensitivity and accuracy, but there is
no evidence in their scientific data for that here.
- The numbers are also inconsistent. The abstract states 142 patients but the
Body states 122 patients.
- A flow chart would be useful here to show what actually happened. It appears
Included patients were those that already had conventional then NBI/Mag
imaging and HAD Histo confirming a lesion. But were there patients that had a
lesion on conventional endoscopy but not on the other 2 methods and no lesion
found on histo??? If so this would address accuracy issues. Also, categorically
did these patients not have any biospies after their inital endoscopy finding a
lesion?
Minor Essential Revisions:
- Labelling on figure 1 - Photos not marked A/B/C/D
- Abstract states is retropective study but main body states is prospective study
(again in Background of main body states is retrospective). This needs to be
clarified.
Discretionary Revisions:
- They could talk about potential problems of over sensitivity (Reduced
specificity)
Level of interest: An article of importance in its field
Quality of written English: Needs some language corrections before being
published
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