Title: Group-based physical activity interventions for postpartum women with children aged
0-5 years old: A systematic review of randomized controlled trials
Version: 1 Date: 10 Jul 2021
Reviewer's report:
The topic of this systematic review is very relevant with the increasing campaigns to encourage
physical activity among postpartum women worldwide. It is timely to synthesize evidence
regarding the effectiveness of group-based physical activity interventions for postpartum women
with children aged 0-5 years old. Building upon previous reviews, the authors examined the
impact of group-based PA interventions on postpartum women’s PA levels or other behavioural
outcomes.
A total of 6 trials was included for synthesis. The authors reported that group-based PA
interventions were moderately successful in enhancing postpartum women’ self-reported PA
levels and psychological wellbeing in the first two years of their offspring’s life while it may
not be successful in changing or increasing postpartum women’ PA levels when measured
objectively. I agree with the authors’ decision not to merge the data using meta-analysis due to
the clinical heterogeneity of the trials. Good choice. However, I have several major concerns: 1)
the thoroughness of the electronic search; 2) software used for reference management; 3) Lack
of clarity in the narrative synthesis; 4) aim of the study. My detailed comments are as follows.
In general
• This manuscript will benefit substantially from thorough English editing. Also, the punctuation
structure of sentences is not very coherent, thereby explaining the lack of clarity throughout the
manuscript. Eg, in the abstract “Worldwide it is estimated…”
Abstract
• Recommend defining all abbreviation when it is introduced in the first time. E.g. Physical
activity (A) in line 3
• Page 2, line 7: What do you mean by inactive women? Please be more explicit.
• Page 2, line 15: Typo error for indentifed?
• Results: I thought your objective is on health behaviour outcomes? why do you report the
psychological wellbeing instead? I assume that health behavior outcomes = psychological
wellbeing?
Introduction
• Generally, the literature review has very good information, but your team needs to tighten
it to critically synthesize the evidence. Some of the paragraphs can be summarize into one.
More focus should be on evidence on group-based interventions (one paragraph) and why is it
important among postpartum women with children (one paragraph)
• Page 7, line 2-3: rephrase of the sentence for “if members… accomplishing goals” as lack
clarity
• Page 7, line 4-5: You mentioned high-risk populations and those most in need, but your
subsequence sentences didn’t seem to substantiate that points. E.g. a) male and females? [Are
they high-risk? most in need?], b) disparate health statuses [quite generic, need to be more
explicit]
• Page 7, line 11: What are the competing demands?
• Page 7, line 12-14: This is a good point, and you should expand on this. What are other
mechanisms in group-based interventions? This will highlight the novelty of your review.
• Page 7, line 16-24: More work needs to be done to address the current review gaps
and critically synthesize the gaps I agree that ref 34 and 35 are classical similar reviews
highlighting personalised exercise. But I am also looking forward to other reviews that highlight
psychological wellbeing/ mental health/ health behavioral outcomes which are your secondary
outcomes:
You can explore the following reviews:
https://www.sciencedirect.com/science/article/abs/pii/S0165032718318779
https://www.sciencedirect.com/science/article/abs/pii/S0301211519301277
https://link.springer.com/article/10.1007/s00737-017-0750-9
Methods
• Page 8, line 8-9: Why do your team only search 4 databases? Since your team focus on rct,
why not search through Cochrane library? and why was medline chosen over pubmed? Your
team could potentially miss out some trials, hence I doubt the thoroughness of the search.
• Secondly, is there a particular reason for restricting to past 20 years? You need to have a good
justification for these restrictions. I believe group-based exercise have been around for more
than a couple of decades.
• Thirdly, why did your team included the search terms for design (i.e., rct) as you may filter
away a lot of potential trials. I suggest your team to consult university library for a more
robust search terms and present the different search strategies for individuals’ databases in
the supplementary materials. There is a need to combine index (MeSH for Pubmed/Cochrane,
Emtree for EMBASE) and keywords in all your search. I am also concern why “leadership” is
part of setting?
• Page 9, line 6—9: Resequencing the sentence is suggested as it is confusing. Reported PA
measured objectively…and/or subjective, and other health behavioral outcomes (…). Why
is BMI part of health behavioral outcomes? Isn’t this clinical outcomes? How about your
other outcomes listed in the protocol? QoL, cardiovascular outcomes, incontinence and milk
production, etc. ?
• Any referencing software used for duplication of references? Eg. Endnote, Mendely, etc.
• Page 9, line 20-21: “Meta-analytic approach…. methodological framework.” It was repeatedly
mentioned in Page 10, line 11-12. Suggest combining.
Results
• Page 10: Please provide the lists of excluded studies (N=87) in the appendix and removed
“show/hide” in the Figure 1 before you export as picture.
• Description of studies: Suggest revising the Table 2 critically to enhance clarity. Probably you
can split into 2 tables.
1) Characteristics of selected trials
2) Description of interventions
• Page 11, line 6: I think the earliest one was 2006 while the latest was 2017
• Page 14, line 8-9: Good to have your new Table 1 to include the design of the trial, comparator,
attrition rate, ITT/missing data management, protocol publication/ registration?
• Summary of intervention effect: Need to work on this paragraph extensively. You need
synthesize the data that you have and not narratively describe the interventions and designs.
Currently, you mentioned about the outcomes, then you mentioned about the intervention details.
If you are focusing on the impact on outcomes, just synthesize all available trials that talk about
the same outcomes and any conflicting findings?
• Subthemes for psychological wellbeing: Need to clarify if health behavioral outcomes =
psychological wellbeing. Psychological wellbeing is a broad term, you need to define and
introduce this term if you are using it.
• Page 16, line 3-4: “to postpartum women’s daily caloric intake, self-reported PA, TV hours/
day or body weight.” Are these psychological well-being outcomes?
• Narrative synthesis: This section seems like the description of the interventions in details
(suggested table 2) and not really synthesizing.  You need to refer to your review objectives.
You are looking at the outcomes? unless you have a secondary objective that explore the optimal
designs/ contents/ delivery mode of the group-based PA interventions. Currently, your review
aims to explore the impact of group-based PA interventions on postpartum womens’ PA levels
or other behavioural outcomes.
• Page 16, line 14: Your team infer the narrative synthesis from quality assessment?
Discussion:
• This section require major revision after the issues are addressed as mentioned above.
• Please reorganize your paragraph. Consider beginning with summary of key findings, Quality
assessment findings, specific outcomes findings (If similar to previous review, why? If different,
why?), strengths and limitations, followed by conclusion.
Figure 1:
• Why you report the outcomes under the last box? Please follow the guidelines stipulated in the
PRISMA manual and cite PRISMA in your results section.