Reviewer's report
Title:Upper Gastrointestinal Bleeding due to Peptic Ulcer Disease is Not
Associated with Air Pollution: A Case-Crossover Study
Version:1Date:17 July 2015
Reviewer: Ilva Daugule
Reviewer's report:
The idea about the association between gastrointestinl bleeding and air pollution
is interesting and original, therefore also negative results (observed in the study)
could be of importance.
The design is original, although complicated for individuals not involved in
environmental research. The main conclusion – no association between air
pollution and upper GI bleeding – is clear. The study could be improved by
analysis of other factors that could influence gastrointestinal bleeding.
Major Compulsory Revisions
Multiple regression analysis could be performed to evaluate the impact of other
factors (age, comorbidities, season, possibly – H.pylori infection).
Minor Essential Revisions
• Conclusions – no need to repeat hypothesis.
• Add references in the following sentences:
Despite advances in management, the risk for mortality among patients with this
condition ranges from 2.2% upward to 14% .
The primary risk factors for PUD are non- steroidal anti-inflammatory drugs
(NSAIDs) and Helicobacter pylori. However, a significant proportion of PUD is not
explained by these risk factors.
Discretionary Revisions
• The author could add some ideas in discussion part, how air pollution could
promote ulcer bleeding.
• The role of comorbidities, seasonality, age and complications could be more
analysed in respect to air pollution.
If possible, data about H.pylori infection could also be extrapolated from the
databases – this could help to differentiate H.pylori related ulcers and other
ulcers. May be there is an association between air pollution and only non-H.pylori
ulcers.
The level of air pollution differs in both cities – how this could affect differences in
discovery and replication cohort.
• The following sentence in discussion part is misleading – it seems that the
authors suggests that acute exposure actually triggers an UGIB. Try to change
the sentence.
Our discovery and replication cohorts did not demonstrate any statistically
significant associations suggesting that acute exposure triggers an UGIB
secondary to PUD.
Level of interest: An article whose findings are important to those with closely
related research interests
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:Upper Gastrointestinal Bleeding due to Peptic Ulcer Disease is Not
Associated with Air Pollution: A Case-Crossover Study
Version:1Date:17 July 2015
Reviewer: Ilva Daugule
Reviewer's report:
The idea about the association between gastrointestinl bleeding and air pollution
is interesting and original, therefore also negative results (observed in the study)
could be of importance.
The design is original, although complicated for individuals not involved in
environmental research. The main conclusion – no association between air
pollution and upper GI bleeding – is clear. The study could be improved by
analysis of other factors that could influence gastrointestinal bleeding.
Major Compulsory Revisions
Multiple regression analysis could be performed to evaluate the impact of other
factors (age, comorbidities, season, possibly – H.pylori infection).
Minor Essential Revisions
• Conclusions – no need to repeat hypothesis.
• Add references in the following sentences:
Despite advances in management, the risk for mortality among patients with this
condition ranges from 2.2% upward to 14% .
The primary risk factors for PUD are non- steroidal anti-inflammatory drugs
(NSAIDs) and Helicobacter pylori. However, a significant proportion of PUD is not
explained by these risk factors.
Discretionary Revisions
• The author could add some ideas in discussion part, how air pollution could
promote ulcer bleeding.
• The role of comorbidities, seasonality, age and complications could be more
analysed in respect to air pollution.
If possible, data about H.pylori infection could also be extrapolated from the
databases – this could help to differentiate H.pylori related ulcers and other
ulcers. May be there is an association between air pollution and only non-H.pylori
ulcers.
The level of air pollution differs in both cities – how this could affect differences in
discovery and replication cohort.
• The following sentence in discussion part is misleading – it seems that the
authors suggests that acute exposure actually triggers an UGIB. Try to change
the sentence.
Our discovery and replication cohorts did not demonstrate any statistically
significant associations suggesting that acute exposure triggers an UGIB
secondary to PUD.
Level of interest: An article whose findings are important to those with closely
related research interests
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:Upper Gastrointestinal Bleeding due to Peptic Ulcer Disease is Not
Associated with Air Pollution: A Case-Crossover Study
Version:1Date:17 July 2015
Reviewer: Ilva Daugule
Reviewer's report:
The idea about the association between gastrointestinl bleeding and air pollution
is interesting and original, therefore also negative results (observed in the study)
could be of importance.
The design is original, although complicated for individuals not involved in
environmental research. The main conclusion – no association between air
pollution and upper GI bleeding – is clear. The study could be improved by
analysis of other factors that could influence gastrointestinal bleeding.
Major Compulsory Revisions
Multiple regression analysis could be performed to evaluate the impact of other
factors (age, comorbidities, season, possibly – H.pylori infection).
Minor Essential Revisions
• Conclusions – no need to repeat hypothesis.
• Add references in the following sentences:
Despite advances in management, the risk for mortality among patients with this
condition ranges from 2.2% upward to 14% .
The primary risk factors for PUD are non- steroidal anti-inflammatory drugs
(NSAIDs) and Helicobacter pylori. However, a significant proportion of PUD is not
explained by these risk factors.
Discretionary Revisions
• The author could add some ideas in discussion part, how air pollution could
promote ulcer bleeding.
• The role of comorbidities, seasonality, age and complications could be more
analysed in respect to air pollution.
If possible, data about H.pylori infection could also be extrapolated from the
databases – this could help to differentiate H.pylori related ulcers and other
ulcers. May be there is an association between air pollution and only non-H.pylori
ulcers.
The level of air pollution differs in both cities – how this could affect differences in
discovery and replication cohort.
• The following sentence in discussion part is misleading – it seems that the
authors suggests that acute exposure actually triggers an UGIB. Try to change
the sentence.
Our discovery and replication cohorts did not demonstrate any statistically
significant associations suggesting that acute exposure triggers an UGIB
secondary to PUD.
Level of interest: An article whose findings are important to those with closely
related research interests
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