Reviewer ’s report  
 
Title: The prevalence  of primary ovarian insufficiency in Sweden; a national register study.  
 
Version: 0 Date: 01 Dec 2017  
 
Reviewer: Aleksandar Rajkovic  
 
Reviewer's report:  
 
Major comments: The manuscript is an important epidemiologic addition to the prevalence of 
POI. POI is associated with a number of adverse health outcomes, and knowing its prevalence is 
important for public health measures, counseling and intervention. The  manuscript concludes 
that close to 2% of individuals in the Swedish registries appear to carry the diagnosis of POI. 
Below are my concerns:  
 
1. The data was obtained from two registries. The denominator of each registry is unclear. Is 
1.9% prevalence same  in both registries? If not, this needs to be discussed.  
2. In the drug registry, was diagnosis attached to the prescription for HRT?  
3. What was the purpose of the Birth registry?  
4. What percent of the individuals in the registry reached aged 40, 45, 50 ? Were individuals 
younger than age 40 excluded? What is the incidence of POI per age groups, <20, 20 -30, 
30-40, 40 -50? 
5. The authors need to discuss gynecologic indications for HRT in individuals under 50 and 
presumably with intact uterus. Was HRT taken short term or long term? Could it have 
been used to improve sexual drive, bladder problems, or other indications among 
Swedish women? the pattern of HRT prescription varies between countries and among 
physicians.  
6. What was the age distribution of indivi duals that received HRT only treatment?  
7. Oophorectomy was considered as iatrogenic POI. How about hysterectomy? 
Hysterectomy can cause POI by altering ovarian blood supplies.  
8. the authors state "two or more dispensations" of HRT. how frequently were these 
dispensations?  
 
  
General comments on the writing/execution of the manuscript that should be addressed before 
publication:  
- The background section of the abstract needs to be completely rephrased.  
- The oxford comma should be utilized, and compoun d sentences should have a comma 
before their conjuncture.  
Example (Lines 48 -50) "The causes of spontaneous POI remain unknown in 90% of the cases, 
but may be caused by chromosomal abnormalities, gene mutations, autoimmunity disorders, and 
infections."  
- Some numbers are missing commas designating the thousandth place.  
Example (Line 55) "…total of 1,858 women …"  
- Line 80, remove comma before "with".  
- Results section Line 119 - 126 utilizes "i.e." phrasing way too often and it is distracting to 
the reade r.  
- Line 170, is this a subheading? An incomplete sentence? It is unclear.  
- Table 1 is written in the text, but the Table is labeled as Table I. Both tables (1 and 2) are 
missing commas, and could be formatted nicer.  
- In general, the discussion felt repetitive/redundant. Time should be taken by the writers to 
make the discussion more concise and address above major concerns.  
 
 
 
 
 
 
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.  
 
Unable to assess  
 
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 manuscript or would you recommend an  
additional statistical review?  
If an addition al statistical review is recommended, please specify 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:  
 
Needs some language corrections before being published  
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, fees, funding, or salary from an  
organisation that may in any way gai n or lose financially from the publication of this  
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose  
financially from the publication of this manuscript, either now or in the fu ture?  
 
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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