Review for 10.1186/s12876-019-1057-2 (2019)

Reviewer ’s report  
 
Title: Current Diagnosis and Management of Crohn ’s Disease in China: Results from a 
Multicenter Prospective Disease Registry  
 
Version: 0 Date : 03 Apr 2019  
 
Reviewer: Jesse Green  
 
Reviewer's report:  
 
In the Statistical Analysis section (Lines 165 -6): 
- You note sample size was determined by "pragmatic consideration": please define pragmatic 
consideration  
 
In the Surgery History section:  
- Lines 224 -227 need grammatical corrections and some words are missing so the meaning of 
the sentences are not clear to the reader  
- Lines 232 -235 require grammatical corrections; many prepositions are missing  
 
In the Disease behavior and Location Classification sect ion: 
- Line 246 -- should be "according to the Montreal classification..... (missing preposition)  
 
In the Medical Treatment and Disease Activity section:  
- Lines 258 -259 -- should read patients achieved remission (as opposed to "got remission")  
 
Discussion  Section  
- Extensive grammatical correction is necessary -- there are problems with word usage, verb 
conjugation, missing prepositions, and errors pertaining to the use of plural versus singular 
nouns  
- Line 339: please define "conventional therapy"  
 
• This prospective, multicenter disease registry provides important data regarding the 
demographics and clinical manifestations of confirmed Crohn’s disease (CD), by 
geographic region in China, and by anatomic location of Crohn’s disease.  
• The resu lts can be utilized to educate providers regarding earlier diagnosis of CD 
(enabling the initiation of earlier potentially disease modifying therapy) and aid in 
differentiating CD from TB (a key differential diagnostic consideration in China).  
• Data  was collected from a relatively small sample size of 500 patients from 14 centers 
representing all regions of China (see my recent comment regarding how “pragmatic 
considerations” can be defined as applied to sample size selection – possible selection 
bias) 
• The data was assessed through a validated clinical disease activity scoring system 
(CDAI) and a validated scoring system for disease location and behavior (The 
Montreal Classification).  
• Logistic regression and stepwise multivariate regression analyses were employed to 
calculate ORs and 95% Cis; the statistical analyses were appropriate.  
• The finding that the mean (SD) duration from disease onset to initial definitive 
diagno sis decreased significantly from 2010 to 2015.  
• The proportion of patients who had undergone CD -related surgery (48.5%) comports 
with experience in other countries.  
• Disease location (ileocolic, L3), phenotype (penetrating, B3), liver disease ,  male 
gender, fam hx of diabetes, and current smoking status all  correlated with a higher 
likelihood of having had CD -related surgery; these observations might serve as simple, 
inexpensive predictors for patients in China and elsewhere who warrant early  initiation 
of potentially disease modifying therapy.  
• This study also noted that increased duration from disease onset or definitive diagnosis 
of CD to enrollment in the database is associated with a higher risk of B2/structuring 
disease – this sug gests that progression to fibrostenotic disease parallels what has been 
demonstrated in published Western studies – again providing rationale for education, 
earlier diagnosis and implementing earlier effective CD therapy.  
• A significant variance fro m what we be expected is that less than 50% of patients were 
receiving immunomodulators and only 1/5 were on 5ASAs (not effective for CD) or 
steroids; there is no mention of biologic or small molecule therapy.  
• The discussion mentions differences in  gender distribution and the absence of a 
bimodal age distribution in Asian versus Western populations that was observed in this 
study; also, 50% of CD patients in this and prior Chinese and Asian studies had B1 
disease compared to 80% in Western populatio ns – the authors plausibly note this may 
due to: 1) their patients were not newly diagnosed so the disease progressed, 2) 
increased smoking rate in their patients  
• The authors postulate that the lower prevalence of EIMs in Asian v Western (11% v 
25-40%) may be associated with relatively better prognoses – I am unsure if this is 
correct  
• I agree with the authors’ concern for selection bias as noted in their discussion (see my 
comment above).  
• As I mentioned in my initial review, the auth ors describe “conventional therapy” in the 
discussion, but should define this so readers across the globe can understand the current 
medical approaches in China – this might imply that their lower proportion of B1 
patients could be related to the use of bi ologics in China as second -line therapy – and 
may support the generally held belief that earlier biologic Rx can, indeed, delay 
progression to more advanced disease (B2, B3). Table 1 CD treatment information 
section lists the percentages of CD treatments i n their sample, but additional discussion 
would inform the reader with respect to current CD treatment approaches in China.  
• Although usage of anti TNFs in China (approx. 33% in this study) appears higher when 
compared to other Asian countries (suc h as 11% in Hong Kong) – the current findings 
of a higher proportion of B2 and B3 disease in China compared to Western countries 
may prompt China’s IBD specialists to re -consider their CD treatment algorithms.  
• In conclusion, this is a scientificall y valid study using appropriate statistical analyses. It 
provides important information that can improve the diagnosis and management of CD 
patients in Asian and Western countries. In China, these study findings may guide IBD 
care resource allocation by re gion and lead to earlier CD diagnosis through clinical 
education; they may also facilitate the differentiation of CD from TB.  
 
Prior to acceptance, the grammar and syntax should be corrected, and definitions provided, for 
“pragmatic considerations” and “co nventional therapies  
 
Are the methods appropri ate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
Yes 
 
Are the conclusions d rawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
 
Yes 
 
Are you able to assess any statistics in the manus cript or would you recommend an 
additional statistical review?  
If an additional statistical review is recommended, please speci fy what aspects require further 
assessment in your comments to the editors.  
 
I recommend additional statistical review  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Not suitable for publication unless extensively edited  
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
1. Have you in t he past five years received reimbursements, f ees, funding, or salary from an 
organisation that may in any way gain or lose financial ly from the publication of this 
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisat ion t hat may in any way gain or lose 
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents  relating to the content of the 
manuscript?  
 
4. Have you received reimbursemen ts, fees, funding, or salary from an organization that holds 
or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing interests in relation to t his paper?  
 
If you can answer no to all of the above, write 'I declare that I have  no competing interests' 
below. If your reply is yes to any, please give details below.  
 
I will be serving on a Pfizer advisory board in April 2018.  
 
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