Reviewer's report 
 Effect of oral lactulose on clinical and immunohistochemical parameters in patients with inflammatory Title: 
bowel disease: a prospective, randomised and controlled pilot study. 
 2  16 May 2007 Version: Date: 
 Elias Zintzaras Reviewer: 
Reviewer's report: 
I have major concerns about the study quality and statistical analysis/results. 
Some of my comments are the following: 
Although the authors reported a pilot study of 31 patients, based on the performed analysis actually we 
have a study of 14 patients with UC and a study of 17 CD. These numbers are really very small for testing 
clinical efficacy and claiming significance. 
The study was designed as a prospective randomized parallel study, however, the loss in follow-up was 
31/52=40%, a very large number questioning the quality of the study. 
Furthermore, it not clear how many of the 31 patients completed the 4 months follow-up. 
The authors do not report and do not compare disease severity for groups L and C at baseline. It is not valid 
to compare the groups when disease severity is different at baseline. 
Summary statistics, and comparisons, of age, gender, follow-up at baseline and at end of follow-up are not 
provided. 
There are too many comparisons and the chance of false positive results is quite high. 
The statistical analysis is not clear: how the difference between L and C is tested for IBDQ and other 
responses? What is the "multivariate tests"? How an adjustment was performed? What are the unadjusted and adjusted resulst? In addition, t-test is not valid for small samples. 
 Reject because scientifically unsound What next?: 
 An article of limited interest Level of interest: 
 Acceptable Quality of written English: 
 No, the manuscript does not need to be seen by a statistician. Statistical review: 
Declaration of competing interests: 
'I declare that I have no competing interests' 
Reviewer's report 
 Effect of oral lactulose on clinical and immunohistochemical parameters in patients with inflammatory Title: 
bowel disease: a prospective, randomised and controlled pilot study. 
 2  16 May 2007 Version: Date: 
 Elias Zintzaras Reviewer: 
Reviewer's report: 
I have major concerns about the study quality and statistical analysis/results. 
Some of my comments are the following: 
Although the authors reported a pilot study of 31 patients, based on the performed analysis actually we 
have a study of 14 patients with UC and a study of 17 CD. These numbers are really very small for testing 
clinical efficacy and claiming significance. 
The study was designed as a prospective randomized parallel study, however, the loss in follow-up was 
31/52=40%, a very large number questioning the quality of the study. 
Furthermore, it not clear how many of the 31 patients completed the 4 months follow-up. 
The authors do not report and do not compare disease severity for groups L and C at baseline. It is not valid 
to compare the groups when disease severity is different at baseline. 
Summary statistics, and comparisons, of age, gender, follow-up at baseline and at end of follow-up are not 
provided. 
There are too many comparisons and the chance of false positive results is quite high. 
The statistical analysis is not clear: how the difference between L and C is tested for IBDQ and other 
responses? What is the "multivariate tests"? How an adjustment was performed? What are the unadjusted and adjusted resulst? In addition, t-test is not valid for small samples. 
 Reject because scientifically unsound What next?: 
 An article of limited interest Level of interest: 
 Acceptable Quality of written English: 
 No, the manuscript does not need to be seen by a statistician. Statistical review: 
Declaration of competing interests: 
'I declare that I have no competing interests' 
Please review this paper.
user
Reviewer's report 
 Effect of oral lactulose on clinical and immunohistochemical parameters in patients with inflammatory Title: 
bowel disease: a prospective, randomised and controlled pilot study. 
 2  16 May 2007 Version: Date: 
 Elias Zintzaras Reviewer: 
Reviewer's report: 
I have major concerns about the study quality and statistical analysis/results. 
Some of my comments are the following: 
Although the authors reported a pilot study of 31 patients, based on the performed analysis actually we 
have a study of 14 patients with UC and a study of 17 CD. These numbers are really very small for testing 
clinical efficacy and claiming significance. 
The study was designed as a prospective randomized parallel study, however, the loss in follow-up was 
31/52=40%, a very large number questioning the quality of the study. 
Furthermore, it not clear how many of the 31 patients completed the 4 months follow-up. 
The authors do not report and do not compare disease severity for groups L and C at baseline. It is not valid 
to compare the groups when disease severity is different at baseline. 
Summary statistics, and comparisons, of age, gender, follow-up at baseline and at end of follow-up are not 
provided. 
There are too many comparisons and the chance of false positive results is quite high. 
The statistical analysis is not clear: how the difference between L and C is tested for IBDQ and other 
responses? What is the "multivariate tests"? How an adjustment was performed? What are the unadjusted and adjusted resulst? In addition, t-test is not valid for small samples. 
 Reject because scientifically unsound What next?: 
 An article of limited interest Level of interest: 
 Acceptable Quality of written English: 
 No, the manuscript does not need to be seen by a statistician. Statistical review: 
Declaration of competing interests: 
'I declare that I have no competing interests' 
assistant