Reviewer ’s report  
 
Title: Pattern and correlates of out -of-pocket payment (OOP) on female ster ilization in India, 
1990 -2014.  
 
Version: 0 Date: 19 Nov 2018  
 
Reviewer: Antoinette D.I. Van Asselt  
 
Reviewer's report:  
The authors of this manuscript have analyzed a large amoun t of data to investigate the situation 
with regard to OOPE and incentives for sterilization services in India. Although this has led to 
some interesting findings, the lack of focus is a problem. The English language also needs 
extensive editing (especially  the discussion section). More specifically, I have the following 
concerns:  
 
- Why use the regression model to estimate the predicted OOPE? Is this truly the outcome of 
interest given the aim of the paper, which is stated as 'to examine trends in incentive s and 
OOPE'? The hypothesis is that OOPE has increased over time, so how does this regression 
analysis fit in there, since it does not prove anything on OOPE over time. I do not mind that a 
regression is performed, but aims, hypothesis, methods and conclus ion should follow the same 
line. Given that it is government policy to promote sterilization, and the incentives to decrease 
OOPE are an instrument to attain this, one would be more interested in predictors for accepting 
sterilization, in the end. It may n ot be possible to do that with the data available but I do think it 
needs more explanation why OOPE is chosen as the dependent variable, and the aims may need 
rephrasing.   
- The methodology for the regression is a bit unclear as well: on p10 (line 21/22) says that the 
analyses were performed the significant predictors of 'incentives and OOPE' and then in line 24 it 
says that a two -part regression is done to obtain the 'predicted mean cost of sterilization'. This 
leaves some confusion as to what is the inde pendent variable in these analyses, is it just the 
OOPE , or something broader?  
- In the interpretation of the regression analyses results in table 5, the reader is unclear on 
whether the logit or OLS betas should be interpreted. Since only the significant  variables for the 
OLS are discussed in the results (p19) I assumed it is the OLS, but further in the paper, also the 
quality of care is referred to as a significant predictor (p22 line 14 -16). 
- What to think of the highly significant and positive beta fo r quality of care 'not good'  - does 
this imply that people pay more for bad quality?  
- After the huge amount of information on per -state OOPE and incentives and trends etc, the 
conclusion that quality of services should be improved comes as a bit of a su rprise. I rather 
expected something like that apparently people do not appreciate or do not know how to obtain 
free sterilization or incentives, and better information to the public, or better access to services is 
necessary. If the authors still think the ir conclusion is the most obvious, they should have 
prepared the way in their interpretation of results.  
 
Please also consider the following suggestions:  
- have a native speaker edit the text  
- reduce the number of tables and figures. In my opinion, table 2 can better be turned into a 
graph, table 3 can be removed (could add percentages of public/private to table 1), and figure 3 
can also be removed. Please add a row/bar for the whole country t o table 1 and figure 2. Tables 
and figures removed from main text can go to suppl material of course - also please explain how 
in table 3, a negative OOPE makes a positive percentage in the same manner as the positive 
OOPE - this is slightly misleading  
- page 8 lines 21 -36 - this is too much detail, should be reduced to essentials, i.e. that data 
cleaning was performed  
- page 9 lines 40 -41 - for the international audience could the authors please expand a bit on the 
exact meaning of the caste variable used in the analyses - I do not know the differences between 
the castes mentioned nor which one is better. Also, why are caste and religion not shown in 
tables 4 and 5?  
- page 21 last line: could the authors explain why high fertility is associated with cost o f 
sterilization? Is that the per patient cost or the total per state cost?  
 
 
 
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
No 
 
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.  
 
No 
 
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 am able to assess the statistics  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Not suitable for publication unless extensively edited  
 
Decl aration 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 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 organisation 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 reimbursements, 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 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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