Reviewer's report
Title:The value of serum pepsinogen levels for the diagnosis of gastric diseases
in Chinese Han people in midsouth China
Version:2Date:6 December 2013
Reviewer: Nayoung Kim
Reviewer's report:
Thanks for your kind answer to my comments. I have more comment as follow;
Major comments:
1. As I commented previously, serum pepsinogen levels are affected by many
factors such as age, gender and so on. I understand the author’s opinion that
due to the small sample size, the authors could not analyzed the other factors. If
so, how about adding mean ages and gender distribution of non-GC group, GC
group and healthy control group in tables? How about adding correlation
(correlation coefficient) between pepsinogen values and age?
2. The statistical methods are incorrect.
1) The author said “analyze the differences in patients with gastric disease and
healthy controls by using paired t-test” Paired t-test is estimating the difference
between two matched population means. In this case, Student’s t-test is correct
method.
2) In statistical method section, “P < 0.05 was considered statistically significant”
and “two-sided P value of less than 0.05 was considered statistically significant”
are overlapping sentences.
3) In statistical method section, the authors said “continuous variables were
shown as mean ± SD and non-normal distribution variables were shown as
median and interval.” However, in table 1, all values are presented as mean ±
SD. Which one is non-parametric data?
3. In page 7, “As shown in Table 5, serum PG I level in the patients with gastric
ulcer and those with duodenal ulcer were 147.58 ± 57.81 µg/L (n = 36) and
217.43 ± 51.12 µg/L (n = 31), respectively, significantly higher than in the
subjects with endoscopically normal mucosa (118.39 ± 47.8 µg/L).” This
sentence is more related with ‘Table 1.’ And I think ‘Table 5’ is meaningless data
because the same result already described in ‘Table 1.’ It would better to delete
the ‘Table 5.’
4. In method section, the authors identified the H. pylori status by RUT and
anti-H. pylori IgG test. Please clarify the definition of current H. pylori infection. Is
the author use both of these methods or one of these method?
Minor comments:
1. In abstract, line 3, serum PG levels instead of serum levels.
2. In introduction, page 4, line 3-4, suggest appropriate references, please.
3. In page 5, line 12, correct P as small letter.
4. Please correct all signs of inequality (#, >) in page 7.
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, and I have assessed the statistics in my report.
Declaration of competing interests:
I declare that I have no competing interests
Reviewer's report
Title:The value of serum pepsinogen levels for the diagnosis of gastric diseases
in Chinese Han people in midsouth China
Version:2Date:6 December 2013
Reviewer: Nayoung Kim
Reviewer's report:
Thanks for your kind answer to my comments. I have more comment as follow;
Major comments:
1. As I commented previously, serum pepsinogen levels are affected by many
factors such as age, gender and so on. I understand the author’s opinion that
due to the small sample size, the authors could not analyzed the other factors. If
so, how about adding mean ages and gender distribution of non-GC group, GC
group and healthy control group in tables? How about adding correlation
(correlation coefficient) between pepsinogen values and age?
2. The statistical methods are incorrect.
1) The author said “analyze the differences in patients with gastric disease and
healthy controls by using paired t-test” Paired t-test is estimating the difference
between two matched population means. In this case, Student’s t-test is correct
method.
2) In statistical method section, “P < 0.05 was considered statistically significant”
and “two-sided P value of less than 0.05 was considered statistically significant”
are overlapping sentences.
3) In statistical method section, the authors said “continuous variables were
shown as mean ± SD and non-normal distribution variables were shown as
median and interval.” However, in table 1, all values are presented as mean ±
SD. Which one is non-parametric data?
3. In page 7, “As shown in Table 5, serum PG I level in the patients with gastric
ulcer and those with duodenal ulcer were 147.58 ± 57.81 µg/L (n = 36) and
217.43 ± 51.12 µg/L (n = 31), respectively, significantly higher than in the
subjects with endoscopically normal mucosa (118.39 ± 47.8 µg/L).” This
sentence is more related with ‘Table 1.’ And I think ‘Table 5’ is meaningless data
because the same result already described in ‘Table 1.’ It would better to delete
the ‘Table 5.’
4. In method section, the authors identified the H. pylori status by RUT and
anti-H. pylori IgG test. Please clarify the definition of current H. pylori infection. Is
the author use both of these methods or one of these method?
Minor comments:
1. In abstract, line 3, serum PG levels instead of serum levels.
2. In introduction, page 4, line 3-4, suggest appropriate references, please.
3. In page 5, line 12, correct P as small letter.
4. Please correct all signs of inequality (#, >) in page 7.
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, and I have assessed the statistics in my report.
Declaration of competing interests:
I declare that I have no competing interests
Please review this paper.
user
Reviewer's report
Title:The value of serum pepsinogen levels for the diagnosis of gastric diseases
in Chinese Han people in midsouth China
Version:2Date:6 December 2013
Reviewer: Nayoung Kim
Reviewer's report:
Thanks for your kind answer to my comments. I have more comment as follow;
Major comments:
1. As I commented previously, serum pepsinogen levels are affected by many
factors such as age, gender and so on. I understand the author’s opinion that
due to the small sample size, the authors could not analyzed the other factors. If
so, how about adding mean ages and gender distribution of non-GC group, GC
group and healthy control group in tables? How about adding correlation
(correlation coefficient) between pepsinogen values and age?
2. The statistical methods are incorrect.
1) The author said “analyze the differences in patients with gastric disease and
healthy controls by using paired t-test” Paired t-test is estimating the difference
between two matched population means. In this case, Student’s t-test is correct
method.
2) In statistical method section, “P < 0.05 was considered statistically significant”
and “two-sided P value of less than 0.05 was considered statistically significant”
are overlapping sentences.
3) In statistical method section, the authors said “continuous variables were
shown as mean ± SD and non-normal distribution variables were shown as
median and interval.” However, in table 1, all values are presented as mean ±
SD. Which one is non-parametric data?
3. In page 7, “As shown in Table 5, serum PG I level in the patients with gastric
ulcer and those with duodenal ulcer were 147.58 ± 57.81 µg/L (n = 36) and
217.43 ± 51.12 µg/L (n = 31), respectively, significantly higher than in the
subjects with endoscopically normal mucosa (118.39 ± 47.8 µg/L).” This
sentence is more related with ‘Table 1.’ And I think ‘Table 5’ is meaningless data
because the same result already described in ‘Table 1.’ It would better to delete
the ‘Table 5.’
4. In method section, the authors identified the H. pylori status by RUT and
anti-H. pylori IgG test. Please clarify the definition of current H. pylori infection. Is
the author use both of these methods or one of these method?
Minor comments:
1. In abstract, line 3, serum PG levels instead of serum levels.
2. In introduction, page 4, line 3-4, suggest appropriate references, please.
3. In page 5, line 12, correct P as small letter.
4. Please correct all signs of inequality (#, >) in page 7.
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, and I have assessed the statistics in my report.
Declaration of competing interests:
I declare that I have no competing interests
assistant