Reviewer's report
Title:Retrospective Observation of Mental Disorders during Pregnancy and
Postpartum Period: Results from the Singapore Mental Health Study
Version:1Date:17 July 2015
Reviewer: Louise Michele Howard
Reviewer's report:
This article looks at prevalence of mental disorders in relation to the perinatal
period and associated risk factors using the Singapore Mental Health Study. It
has a relatively large sample size and the study is well written but there are a
number of methodological problems.
Major Compulsory Revisions
Methods
1. Further information would be useful about the validity of the measure used for
assessment of mental disorder – i.e. has this tool been validated in different
ethnic groups or the perinatal period? Appetite for example, is not a reliable
symptom marker for depression in pregnancy.
2. The onset of pregnancy is estimated and as authors acknowledge the method
used is not accurate. In addition, not all pregnancies last 9 months which will also
impact on assumptions regarding timing. Could the authors examine the
inferences made in more detail and potentially do some sensitivity analyses to
explore the assumptions made regarding timing and impact on reported results.
3. The life table estimation method used needs to be more clearly described in
order to establish if the most appropriate statistical method is used.
4. As sampling was disproportionately stratified the prevalence of mental
disorders shuld either be weighted or stratified by ethnicity.
5. More detail on how the multivariable analysis was carried out is needed – e.g.
were all covariates added at the same time?
Discussion
6. Most of the covariates measured were potentially time dependent - chronic
medical conditions, marital status and employment status. Therefore reverse
causality is an issue for all of the associations and must be discussed as a
limitation.
Minor Essential Revisions
1. The background is relevant though could have emphasised in particular the
evidence gaps in this population ie in Singapore (as readers won’t be familiar
with data from Singapore)
2. The first sentence of the introduction reads a little awkwardly – lines 58-60. A
clause could be removed, for example “physiological, hormonal, psychological
and social role changes make pregnancy and the postpartum a time of potential
vulnerability for various disorders” might read better.
3. Second sentence in the first paragraph of the introduction also reads a little
awkwardly and a native English speaker could be consulted to determine the
correct tense. The word ‘was’ could be changed to ‘have been reported at’ and
the fact that it’s talking about two different studies needs to be clarified I think.
4. The introduction justifies and leads nicely into the research question, covering
the relevant material. The research question is well defined regarding the
temporality of disorders but the objective regarding risk factors needs to be
added to the last paragraph of the introduction.
5. Line 66, 2nd paragraph – add the word ‘may’ between disorders and have
6. Line 67 – instead of the ‘mother is concerned’, change to ‘mother may be
concerned’.
7. Line 76 – can remove clause in brackets (e.g. unresponsive to the needs of
the infant)
8. Line 86 – remove ‘pertaining to these’
9. Last sentence of introduction – line 94-97 may be more suited to being in the
methods section
10. Please add units on figures
11. A table describing the women in the sample would be helpful – i.e.
demographics
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: Yes, and I have assessed the statistics in my report.
Declaration of competing interests:
I declare that I have no competing interests