Review for 10.1186/s12876-019-1128-4 (2019)

Reviewer ’s report  
 
Title: Evaluation of Clinical Risk Factors for Developing Ple ural Empyema Secondary to Liver 
Abscess  
 
Version: 0 Date: 04 Sep 2019  
 
Reviewer: Kittiyod Poovorawan  
 
Reviewer's report:  
 
Reviewer's report: The manuscript entitled "Evaluation of Clinical Risk Factors for Developing 
Pleural Empyema Secondary to Liver Abscess" This study aims to investigate the clinical 
manifestation and predi ctive risk factors of pleural empyema among pyogenic liver abscess 
patients. The article reveals spectrum of clinical manifestations and some associated factors of 
pleural effusion and empyema.  
 
 
Reviewer's Comments  
 
1. Amoebic liver abscess is one importan t causes of liver abscess and sometime associated 
with pleural complications. In this study, why this type of liver abscess was excluded.  
 
2. In case example in Figure1 and 2, authors should demonstrate the relevant with the study 
objective, there is no sp ecific link into article text. In figure2, if there are some specific 
clinical characteristics of liver abscess associated pleural empyema that is different from 
usual empyema thoracis, authors should describe and discuss. If not, this figure seems to 
be unnecessary.  
 
3. This results part "Among patients who developed pleural effusions, presences of mixed 
microorganisms on culture (HR=10.62, p=0.044), bilateral pleural effusion (HR=46.72, 
p=0.012) and biliary disease (HR=21.05, p=0.040) were significantly a ssociated with the 
need for invasive intervention including surgery on effusion." These factors sometimes 
develop after invasive procedure, eg. mixed microorganisms on culture some time can be 
found after drainage, how can authors confirm that these are le ading cause, not a 
complication.  
 
Declaration of competing interests: I declare that I have no competing interests.  
 
Are the methods appropriate 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 drawn 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:  
 
Accep table  
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
 
1.  Have you in the past five years received reimbursements, f ees, funding, or salary 
from an organisation that may in any wa y 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 organisation t hat may in any way gain or 
lose financially from the publication of this manuscript, either now or in t he 
future?  
 
3.  Do you hold or are you currently applying for any patents  relating to the content 
of the manuscript?  
 
4.  Have you received reimbursements, fees, funding, or salary from an organization 
that holds or has applied for patents relating to the cont ent of the manuscript?  
 
5.  Do you have any other financial competing interests?  
 
6.  Do you have any non -financial competing interests in relation to this 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 declare that I have no competing interests  
 
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