Title: Time to First Birth and Its Determinants among Married Female Youths in Ethiopia, 2020:
Survival analysis based on EDHS 2016.
Version: 3 Date: 30 Mar 2021
Reviewer's report:
1. Abstract
a. Methods
Rearrange the sentences in order like how you get the data, how many samples you take from
the data, the models you used to analyze the datasets, etc.
b. Conclusion
This is basically a repetition of the results part. Rephrase by stating what the results mean
in terms of significance. Similarly, you said “The time to first birth in Ethiopia is mainly
influenced by sociodemographic and reproductive related factors. Therefore, the government of
Ethiopia in collaboration with ministry of health and ministry of education should work on these
determinants” but in Ethiopia they work collaboratively and they increase the median time to
give first birth especially in areas(Gojjam, Gondar) in which early marriage and early birth.
2. Introduction
Clear and well stated.
From the sentence “Therefore, the major objective of this research project was to determine time
to first birth and to identify its determinants among married youth females” remove the word
“Major”.
3. Methods
a. Study design and setting
-This part needs some structural changes
- Better to move area information and data source together with the paragraph on the study
population and rename it (might be study setting, data source, and population or simply data
source and population). So here you have to clearly state how you accessed the data from the
DHS program (write the website you used to access it).
-the first sentence “Survival analysis was used to identify the determinants of age at first birth”
is about the model you used rather than the study setting. Therefore remove it.
-What is the study period? Rewrite it clearly, please!
- “The median age at first marriage and first sexual intercourse 17.1 years and 16.6 years
respectively. In this survey the maternal mortality ratio was 412 per 100,000 live births, skilled
delivery coverage was 28%, the contraceptive prevalence among married women and a fertility
rate was 36% and 4.46 respectively. What is this? Is it your finding or reports of the country?
b. Rationale for use of survival analysis
-Take the paragraph and move to the introduction section accordingly.
-What does mean traditional regression? Is there any regression type called traditional?
c. Operational definitions
Event:  simply say it “giving first birth”
Censored: not giving first birth
Survival time: The time is taken in years (age) from her birth to give her first birth.
And remove this sentence “The beginning of the follow up: it started from birth”
d. Sample size and sampling methods
-Since there is no sample size calculation presented I would not call it sample size determination.
I would rather call it sampling.
- "The details of the DHS sampling techniques are available at    https://www.dhsprogram.com.
The data were extracted for all married youth females (15– 24 years) except those who were
declared as infecund (Figure 1)”. Rephrase it and move to data source and population part. Rather
than saying the details of sampling techniques are available at https://www.dhsprogram.com it
is better to say we obtain the data from this website and all sampling procedures are available
at the EDHS reports of each year.
e. Data Processing and Analysis
-Before any statistical analysis, the data should be weighted using sampling weight for
probability sampling and non-response to restore the representativeness of the survey and get
reliable statistical estimates.
- have you weighted data by sampling weight? I didn’t see anything which talks about it.
- The EDHS data were collected from 645 enumeration areas and there might be a variation
between and within-cluster or enumeration areas. Therefore frailty model is a random-effects
model which has an unobserved multiplicative effect on the hazard rate for all the individual
in the same group. But you didn’t fit the frailty model. Did you fit?  If no, how you controlled
the random effect in your model?
-and in this part, you have to write only about data processing and analysis. Therefore, rephrase
it and remove sentences that talk about extra.
4. Result
Table title could be more specific (the time should be 2016)
5. Strength and Limitation of the research
- write only your strengths and limitations when you conducted your study.
-not write the limitations of the study designs as a limitation.
6.  Conclusion
- Why do you express this finding in such a dry and cryptic way?
-rephrase what the median survival time means and list the factors associated with first birth
without repeating the way you report results.
- And also revise your recommendations based on your findings.