Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis

Yitayish Damtie; Bereket Kefale; Melaku Yalew; Mastewal Arefaynie; Bezawit Adane

doi:10.1371/journal.pone.0246348

. 2021 Feb 3;16(2):e0246348. doi: 10.1371/journal.pone.0246348

Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis

Yitayish Damtie ^1,^*, Bereket Kefale ^1,^#, Melaku Yalew ^1,^#, Mastewal Arefaynie ^1,^‡, Bezawit Adane ^2,^‡

Editor: Mohammad Rifat Haider³

PMCID: PMC7857626 PMID: 33534830

Abstract

Background

Closely spaced birth increases the risk of adverse maternal and child health outcomes. In Ethiopia, the prevalence of short birth spacing was highly variable across studies. Besides, contraceptive use, educational status, and duration of breastfeeding were frequently mentioned factors affecting short birth spacing. Therefore, this meta-analysis aimed to estimate the pooled prevalence of short birth spacing and its association with contraceptive use, educational status, and duration of breastfeeding among reproductive-age women in Ethiopia.

Methods

International databases: Google Scholar, PubMed, CINAHL, Cochrane library, HINARI, and Global Health were searched systematically to identify articles reporting the prevalence of short birth spacing and its association with contraceptive use, educational status, and duration of breastfeeding among reproductive-age women in Ethiopia. The data were analyzed by STATA/SE version-14 statistical software. The random-effect model was used to estimate the pooled prevalence of short birth spacing and the log odds ratio was used to determine the association. Moreover, egger’s test and I-squared statistics were used to assess publication bias and heterogeneity respectively.

Results

After reviewing 511 research articles, a total of nine articles with 5,682 study participants were included in this meta-analysis. The pooled prevalence of short birth spacing in Ethiopia was 46.9% [95% CI: (34.7, 59.1)]. Significant heterogeneity was observed between studies (I² = 98.4, p <0.001). Not using contraceptives [OR = 3.87, 95% CI: (2.29, 6.53)] and duration of breastfeeding < 24 months [OR = 16.9, 95%CI: (2.69, 106.47)] had a significant association with short birth spacing.

Conclusions

Although a minimum inter-pregnancy interval of two years was recommended by the World Health Organization (WHO), significant numbers of women still practiced short birth spacing in Ethiopia. Duration of breastfeeding and non-use of contraceptives were factors significantly associated with short birth spacing. So, efforts should be made to improve breastfeeding practice and contraceptive utilization among women in Ethiopia.

Introduction

Maternal mortality remains the major public health challenge to the global population. Reports indicated that an estimated 303,000 maternal deaths occurred worldwide and among this, 99% of deaths were from developing countries [1]. The scenario is worst in sub-Saharan Africa (SSA) in which 546 deaths per 100,000 live births were documented as compared to 216 maternal deaths per 100,000 live births worldwide [2, 3]. The recent national health survey data showed that an estimated 412 maternal deaths per 100,000 live births occurred in Ethiopia [4].

Birth spacing, also known as the birth interval is the duration of time between two successive live births [5–7]. World Health Organization (WHO) recommends a minimum inter-pregnancy interval of two years or an inter-birth interval of thirty-three months or more to ensure the maximum health benefits for the mothers and the newborns [8, 9]. Spacing the child for a minimum of two years reduces infant mortality by 50% [10]. There is a significant variation in the practice of birth spacing across developing and developed countries [11]. Women from developing regions usually have short birth spacing than their actual preference [12]. Data from 52 developing countries indicated that over two-thirds of births happened within 30 months since the preceding live birth [13]. Like many other developing countries, short birth spacing is also the problem of Ethiopian in which 41.5% of women practiced short birth spacing [14].

Short birth spacing has been linked with different adverse pregnancy and childbirth outcomes such as low birth weight [15–18], preterm birth [15–20], congenital anomalies [21, 22], autism [23–27], small size for gestational age [15, 20], and neonatal, infant and child mortality [5, 15, 20, 28–31]. Moreover, women with short birth spacing are at high risk of developing hypertensive disorders of pregnancy, anemia, third-trimester bleeding, premature rupture of membranes, and puerperal endometritis [9, 10, 32, 33]. Beyond the maternal and child health implications, closely spaced birth increases population growth, decelerates one’s country economic development, decreases women's productivity, and increases the demand for natural resources [9].

Reducing maternal and neonatal mortality is one of the key targets of Sustainable Development Goals (SDGs) particularly SDG 3 which aimed to reduce the global Maternal Mortality Ratio (MMR) to less than 70 per 100,000 live births and to decrease neonatal mortality below 12 per 1000 live births by the year 2030 [34]. The Ethiopian government is also implementing Health Sector Transformation Plan (HSTP) IV which aimed to reduce MMR from 420 to 199 per 100,000 live births and under five-year, infant and neonatal mortality rates from 64, 44 and 28 to 30, 20 and 10 per 1,000 live births respectively [35]. Optimal birth spacing is an important concept largely used for maternal and child health advocacy, designing family planning policies, and monitoring and evaluation of policies, strategies, and programs related to maternal and child health.

In Ethiopia, different studies were conducted on childbirth spacing [36–44] and a wide range of maternal and service-related factors like maternal educational status [39, 42, 43], contraceptive use [38, 39, 41–44], duration of breastfeeding [39, 42, 43] residence [38, 41], sex of the index child [39, 42], survival status of the index child [38], religion [40], and unwanted pregnancy [40] were identified. However, the prevalence of short birth spacing varies from region to region ranging from 23.3% to 59.9% [39, 40]. In addition to this, there is no country-level study assessing short birth spacing and associated factors among women of childbearing age in Ethiopia. Moreover, maternal educational status, contraceptive use, and duration of breastfeeding are frequently mentioned and clinically important factors affecting short birth spacing even though they have controversial findings across the included articles. Therefore, this meta-analysis aimed to estimate the pooled prevalence of short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding among reproductive-age women in Ethiopia.

The result of this study will serve as an input for program designers and policymakers to design evidence-based interventions related to child spacing. It will also have paramount importance for future researchers interested in related topics.

Materials and methods

Search strategy

A systematic search was conducted on Google Scholar, PubMed, CINAHL, Cochrane library, HINARI, and Global Health to find both published and unpublished research articles. Besides, Addis Ababa Digital Library was also searched to identify unpublished papers. Grey literatures were identified through the input of content experts and the review of reference lists. The searching was carried out from April 1 up to May 30, 2020, and articles published from 1990 up to May 30, 2020, were included in the review. The Endnote software was used for managing articles and removing duplicates identified by our search strategy. The search strategy includes the following keywords: "proportion", "magnitude", "prevalence", "incidence", "Birth spacing", "child spacing", "birth interval", "suboptimal birth intervals", "short birth spacing", "suboptimal child spacing", "optimal birth spacing", "inter-birth interval", "risk factors", "predictors", "factors", "determinants", "associated factors", "married women", "women", "women of childbearing age", "Ethiopia" independently and in combination using “OR” or “AND” Boolean operators (see S1 File). This systematic review and meta-analysis was organized according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA-2009) checklist [45] (see S1 Table). The protocol of this systematic review and meta-analysis was registered in the international prospective register of systematic reviews (PROSPERO) with a specific registration number: CRD42020160922.

Inclusion and exclusion criteria

Studies conducted in Ethiopia, studies involving women of childbearing age, all types of observational studies (Cross-sectional, case-control, and cohort), published and unpublished articles, full-text articles, articles published from 1990 up to May 30, 2020, and articles written in the English language were included in this study. Whereas relevant articles with full texts of which unavailable after two email contacts of the corresponding authors were excluded.

Outcome measurement

This review measured two main outcomes. The first outcome was the overall pooled prevalence of short birth spacing which was computed by dividing the number of women with short birth spacing to the total sample size multiplied by 100. The second outcome was the association between the duration of breastfeeding, contraceptive use, maternal educational status, and short birth spacing.

Data extraction

Three authors (YD, BK, and MY) independently extracted all the necessary data using a standardized data extraction format. The remaining two authors (MA and BA) solved the disagreement raised at the time of data extraction. The corresponding author of the research article was also contacted for clarification and additional information. Data extraction form includes author name, region, study area, publication year, study design, study setting, sample size, response rate, and the number of women with short birth spacing. For the associated factors, frequencies in the form of two by two tables were extracted, and the log odds ratio for each factor was calculated accordingly.

Quality assessment

BK and MY independently assessed the quality of each research article using the Newcastle-Ottawa quality assessment scale (NOS) [46]. The mean score was taken to solve the disagreements between the two authors.

The quality assessment tool has three subdivisions. The first segment deals with the methodological quality, the second subdivision mainly focuses on the comparability of the study, and the third section deals with the statistical analysis and the outcome of the research article. Finally, studies scoring ≥6 out of 10 scales were considered as high-quality research articles.

Data analysis

The relevant data were extracted using a Microsoft Excel spreadsheet and exported into STATA/SE version-14 statistical software for analysis. The heterogeneity between the included articles was assessed by using a p-value for the I² test [47]. The random-effect model was used to estimate the Der Simonian and Laird’s pooled effect as a result of significant heterogeneity between the studies. Besides, subgroup analysis by residence, sample size, and the cutoff point used to measure the outcome variable was done to decrease the random variations among the point estimates of original articles.

Univariate meta-regression analysis was also done by taking sample size, publication year, and response rate as covariates. Moreover, the presence of publication bias was assessed using both the funnel plot and Egger’s test at a 5% significant level [48].

The point estimates with their 95% confidence interval were presented using the forest plot and the log odds ratio was used to determine the association between short birth spacing and maternal educational status, contraceptive use, and duration of breastfeeding.

Results

Study selection

A total of five hundred eleven (511) published and unpublished studies were identified through electronic databases (Google Scholar, PubMed, CINAHL, Cochrane library, Hinari, and Global Health) and digital library search. Of these identified articles, 502 of them were dropped as a result of duplication, by the titles and abstracts, due to the absence of full texts, and as a result of not fulfilling the eligibility criteria. Finally, 9 eligible articles were included for analysis (Fig 1).

Characteristics of the included studies

A total of 9 research articles published from 2011 up to 2019 were included in this meta-analysis. Among the 9 articles, 6 of them were cross-sectional [36–41], 2 of them were case-control [42, 43] and the remaining 1 study was a retrospective follow-up study [44]. This meta-analysis included 4 studies from Oromia region [36, 38, 39, 43], 2 studies from Amhara region [37, 44], 2 studies from SNNP region [41, 42] and 1study from Tigray region [40] with a sample size ranged from 314 [39] to 811 [38, 41]. From the 9 articles, 6 studies with a total of 3,797 women of childbearing age were included to estimate the pooled prevalence of short birth spacing in Ethiopia. The lowest prevalence of short birth spacing (23.3%) was reported from a study done in the Tselemti district, Tigray region [40] whereas the highest prevalence of short birth spacing (59.9%) was observed from a study done in Serbo town, Oromia region [39]. (Table 1).

Table 1. Descriptive summary of nine studies included in the meta-analysis of short birth spacing and associated factors among women of childbearing age in Ethiopia, 2020.

Authors	Publication year	Region	Study Area	Study Design	Sample size	Response rate	Prevalence (%)	Quality score
Shallo and Gobena [36]	2019	Oromia	Dodota woreda	cross-sectional	647	98	49.1	7
Ejigu et al. [37]	2019	Amhara	Debre Markos	cross-sectional	411	98.3	40.9	6
Tsegaye et al. [38]	2017	Oromia	Illubabor zone	cross-sectional	811	98.2	51.2	8
Ayane et al [39]	2019	Oromia	Serbo town	cross-sectional	314	100	59.9	6
Gebrehiwot et al [40]	2019	Tigray	Tselemti	cross-sectional	803	99.6	23.3	7
Yohannes et al [41]	2011	SNNP	Lemo district	cross-sectional	811	96.1	57	8
Hailu et al [42]	2016	SNNP	Arba Minch	Case-control	636	100	--	7
Begna et al [43]	2013	Oromia	Yaballo Woreda	Case-control	636	97.5	--	8
Tessema et al. [44]	2013	Amhara	Dabat district	Retrospective follow up	613	99.5	--	6

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SSNP; Southern Nations, Nationalities, and Peoples.

Prevalence of short birth spacing in Ethiopia

The pooled prevalence of short birth spacing from the six included studies [36–41] in Ethiopia was 46.9%, [95% CI: (34.7, 59.1)]. A random-effect meta-analysis model was used to estimate the pooled prevalence as a result of substantial heterogeneity among the included studies (I² = 98.4, p <0.001) (Fig 2).

To identify the possible source of heterogeneity, univariate meta-regression was conducted using sample size, publication year, and response rate as a factor, but neither of them were not a significant source of heterogeneity (Table 2).

Table 2. Univariate meta-regression analysis to determine factors related to the heterogeneity of the prevalence of short birth spacing in Ethiopia, 2020.

Variables	Coefficient	P-value
Sample size	-0.0412	0.357
Response rate	-1.3660	0.890
Year of publication	-2.7533	0.546

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Besides, the funnel plot was visually inspected for symmetry and there was an asymmetrical distribution of the effect estimates (Fig 3). To confirm this, egger’s test was used and the test statistic showed the absence of significant publication bias (p = 0.606).

Subgroup analysis

Subgroup analysis by residence, sample size, and the cutoff point used to measure the outcome variable was carry out to identify the possible source variation between studies. The analysis showed that residence (both rural and urban) was one of the sources of severe heterogeneity (I² = 98.4, P = 0.000) (Fig 4). However, severe heterogeneity still existed in the subgroup analysis of studies by sample size and the cutoff point used to measure the outcome variable.

The highest prevalence of short birth spacing (58.2%) was observed among studies conducted in rural settings (58.2%) as compared to both (41.1%) (Table 3).

Table 3. Subgroup prevalence of short birth spacing in Ethiopia, 2020 (n = 6).

Variables	Characteristics	Included studies	Sample size	Prevalence (95% CI)
Residence	Rural and urban	4	2,672	41.1 (26.7,55.5)
	Rural	2	1,125	58.2 (55.3,61.1)
Sample size	≤700	3	1,372	49.9 (40.1, 59.7)
	>700	3	2,425	44 (22.4,65.6)
Short birth spacing cut off point	<33 months	3	1,861	37.7 (20.9,54.5)
	<36 months	3	1,936	56 (50.8, 61.1)

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Factors associated with short birth spacing

The association between contraceptive non-utilization and short birth spacing was determined based on the result of six studies [38, 39, 41–44]. The result indicated women who had never used contraception before the conception of the last child were 3.87 times more likely to have short birth spacing as compared to women who utilized contraceptive methods [OR = 3.87, 95%, CI: (2.29, 6.53)]. The random effect meta-analysis model was used to examine the association due to the presence of significant heterogeneity (I² = 90.4%, p<0.001) (Fig 5).

The effect estimates were distributed symmetrically on the funnel plot indicating the absence of publication bias (Fig 6). The result of Egger’s tests also revealed the absence of publication bias (p-value = 0.684).

A total of three studies [39, 42, 43] were included to identify the association between the duration of breastfeeding and short birth spacing. The result of the random-effect meta-analysis showed the odds of practicing short birth spacing was 16.9 higher among women who breastfeed their child less than 24 months as compared to women who breastfeed ≥ 24 months [OR = 16.9, 95%CI: (2.69, 106.47)]. High heterogeneity was observed between the included studies (I² = 93.9%, p<0.001) (Fig 7).

The results of Egger’s tests showed the absence of publication bias (P = 0.748) even though a slight asymmetrical distribution of the effect estimates was observed on the funnel plot (Fig 8).

The association between the educational status of the mother and short birth spacing was also assessed based on the results of three studies [39, 42, 43]. But, pooled estimate showed non-significant association [OR = 1.60, 95%CI: (0.59, 4.31)]. The included articles showed significant heterogeneity (I² = 94.9%, p<0.001) (Fig 9).

The presence of publication bias was assessed using both funnel plots and Egger’s test. The effect estimates were distributed asymmetrically on the funnel plot indicating the presence of publication bias (Fig 10). But Egger’s test objectively confirmed the absence of publication bias (p = 0.876).

Discussion

Although WHO recommended optimal birth spacing to ensure the health of the mother and the newborn [8], 46.9%, [95% CI: (34.7, 59.1)] of reproductive age women practiced short birth spacing in Ethiopia. The finding of this study is in line with the Ethiopian Demographic and Health Survey (EDHS) report (41.5%) [14] and a study done in Tanzania (48.4%) [49]. But, the pooled prevalence of short birth spacing was higher than the studies conducted in Nepal (23%) [50], Bangladesh (24.6%) [18], and Iran (28.5%) [6]. This discrepancy could be due to variation in maternal socio-demographic characteristics, methodological variation (data analysis, study design, and sampling of study participants), the difference in economic status, lifestyle difference, and the difference in the health service utilization. Furthermore, varied study settings (urban and rural) and the difference in the methods applied to measure the outcome variable may have paramount importance for the variation of the findings.

Even if the increasing birth interval was the primary intervention area of the national government, practically, short birth spacing among reproductive-age women was still quite common. Babies delivered from those mothers who practice short birth spacing might experience low birth weight, small for gestational age, preterm birth, and congenital anomalies. Mothers are also at high risk of developing different adverse pregnancy outcomes [15–33]. So, the clinician needs to be aware of different risk factors and should give special emphasis to them in addition to increasing family planning utilization and duration of breastfeeding among women of reproductive age women.

In this study, the result of subgroup analysis by residence (both urban and rural versus rural) indicated, the practice of short birth spacing was significantly higher in rural settings (58.2%) as compared to both (41.1%). This finding is in agreement with the recent EDHS report which indicated that rural women had a high prevalence of short birth spacing than urban women [4]. Access to the health facility, educational, and employment opportunities among women living in urban areas could be responsible for the variation by residence.

Contraceptive non-utilization had a significant association with short birth spacing. This is consistent with studies conducted in Jordan, Manipur, Egypt, Southeastern Nigeria, and Mbarara Hospital [51–55]. The objective of the family planning program is not only to limit the family size but also adequately space the children by delaying pregnancy. Whenever women use contraceptive methods, they are deliberately avoiding short birth spacing and unwanted pregnancy [9].

The duration of breastfeeding also had a significant association with short birth spacing. The finding is in line with studies conducted in Jordan and Southeastern Nigeria [51, 52]. During breastfeeding, a high amount of prolactin hormone is produced as a result of nipple stimulation. The prolactin hormone inhibits ovulation by reducing the release of the gonadotrophic hormone and resulted in post-partum amenorrhea and thereby lengthen the interval between births. On the other hand, a woman with a short duration of breastfeeding might experience short birth spacing as a result of a decreased level of prolactin concentration in the body [56].

Limitations of the study

This systematic review and meta-analysis considered only articles written in English language. Besides, most of the articles included in the analysis were cross-sectional studies and had a small sample size, these might affect the pooled estimates. Conducting meta-analysis with low numbers of studies is another potential limitation of this study which decreases statistical power, permits large standard errors, and leads to publication bias. Moreover, regions may be under-represented since the included studies were from only four regions of Ethiopia.

Conclusions

A significant number of Ethiopian women practiced short birth spacing though a minimum inter-pregnancy interval of two years was recommended by WHO. Duration of breastfeeding and non-use of contraceptives were factors affecting short birth spacing. Based on the finding, Health care providers should counsel women about the importance of optimal birth spacing, breastfeeding, and contraceptive utilization during their antenatal care, delivery, and postnatal care follow-up. Health extension workers should provide house to house education to improve contraceptive utilization and breastfeeding practice in the community.

Supporting information

S1 File. Search strategy used to estimate the pooled prevalence of short birth spacing and its association with contraceptive use, educational status, and duration of breastfeeding among reproductive-age women in Ethiopia.

(DOCX)

Click here for additional data file.^{(12.5KB, docx)}

S1 Table. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist.

(DOC)

Click here for additional data file.^{(64KB, doc)}

S1 Dataset. The data set used to estimate the pooled prevalence of short birth spacing and its association with contraceptive use, educational status, and duration of breastfeeding among reproductive-age women in Ethiopia.

(XLSX)

Click here for additional data file.^{(9.8KB, xlsx)}

Acknowledgments

The authors would like to acknowledge Wollo and Addis Ababa University Library for providing an available online database.

List of abbreviations

EDHS: Ethiopia Demographic and Health Survey
HSTP: Health Sector Transformation Plan
NOS: Newcastle-Ottawa quality assessment Scale
PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analysis
SSA: Sub-Saharan Africa
SDG: Sustainable Development Goals
WHO: World Health Organization

Data Availability

All relevant data are within the manuscript and its Supporting Information files.

Funding Statement

The authors received no specific funding for this work.

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PLoS One. doi: 10.1371/journal.pone.0246348.r001

Decision Letter 0

Mohammad Rifat Haider

2 Oct 2020

PONE-D-20-19678

Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis:

PLOS ONE

Dear Dr. Damtie,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

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We look forward to receiving your revised manuscript.

Kind regards,

Mohammad Rifat Haider, MBBS, MHE, MPS, PhD

Academic Editor

PLOS ONE

Additional Editor Comments:

Take care of the reviewers' comments. Put special emphasis on the English language and grammar.

Journal Requirements:

When submitting your revision, we need you to address these additional requirements.

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

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https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

2. Thank you for including the statement that "The database search was conducted on 'The searching of research articles was carried out from April 1 up to May 30, 2020, and articles published until May 30, 2020, were included in the review.' Please revise this statement to clarify whether all databases were searched from inception, or if there were any limits placed on the publication dates in your search.

3. At this time, we ask that you please provide the full search strategy and search terms for at least one database used as Supplementary Information.

4. Please provide the results of the assessment of publication bias conducted in the meta-analyses. Please provide the funnel plots of the Egger's regression test as a separate Figure in your manuscript.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Yes

**********

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: No

Reviewer #2: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: I thank the editors for the opportunity to review this manuscript. Short birth spacing is a major cause of morbidity among children and women from low- and middle-income countries, and it has a large impact in Sub-Saharan countries. Although the topic is highly relevant, major changes to the manuscript are required.

A significant limitation of the manuscript in its current form is the English. There are many mistakes and inconsistencies that require an urgent revision by a professional copyeditor. The mistakes make the manuscript challenging to read and understand.

Abstract

- in methods: “and determinants of birth spacing in Ethiopia...” is not true. The researchers prespecified the factors they explored. Please clarify.

- results: please describe the number of articles included in the review and in the meta-analyses.

- conclusion: "The practice of short birth spacing in Ethiopia was higher." Please elaborate on this phrase.

Introduction

- Given the considerable number of factors associated with short birth spacing, it is not clear why the authors chose to explore only maternal education, contraceptive use, and duration of breastfeeding. Please clarify what criteria were used to choose the aforementioned factors.

Methods

- Line 95: “Grey literature was identified through the input of content experts.” It is not clear who these experts were and how they were selected and/or approached. Moreover, it is not clear how many studies the experts included and what criteria was used to select the studies.

- Lines 99 to 105: the authors should include the exact search they used in the different databases. A list of terms is not enough. Moreover, please consider uploading the search as an additional file as this will save space.

- Line 105: “This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist.” The PRISMA checklist is preferred for systematic reviews and meta-analysis of experimental studies. The MOOSE guideline is preferred for Meta-Analysis of Observational Studies in Epidemiology (doi:10.1001/jama.283.15.2008). Please refer to the MOOSE reporting guidelines and use them to report the findings of your article.

- Inclusion criteria: the review is supposed to be focused only on studies exploring maternal education, contraceptive use, and duration of breastfeeding. However, this is not reflected in the inclusion criteria. Please clarify.

- Study setting: I suggest the authors to move this information to the introduction.

- Outcome measurement: There will be many different definitions or cut-off points among the three factors that the authors wanted to explore in their systematic review. For example, the authors will find studies exploring duration of breastfeeding with cut-off points of 6, 8, 12, 18, and 24 months. It is not clear why the authors pre-specified their cut-off point to be 24 months. Moreover, it is not clear why the authors pre-specified their education contrast to be formal education vs no formal education, or contraceptive use yes vs no. Pre-specifying these contrasts would exclude many articles. This should be explained in the limitations section. Additionally, this information is not explained in the inclusion criteria. Please clarify.

Results

- The authors reported high heterogeneity among the included studies. Why did the authors decide to conduct meta-analysis instead of providing a narrative synthesis of the results? Please clarify this sensitive issue.

- From the first paragraph of Results, it seems that the authors conducted a two-step screening phase. First, they screened the titles, and second, they screened the abstracts of the publications. In systematic reviews, however, titles and abstracts are evaluated together. I believe that screening the references in the way the authors did could introduce major biases in the review results. Please explain the rationale behind the two-step screening process.

- First paragraph of Results: the authors overexplain the flow diagram of the articles screened/included. This information could be easily summarized in Figure 1.

- In lines 181 to 184, the authors say that they included 7 studies in the meta-analysis. It is not clear why the authors included only these 7 studies from the original 9 included studies. More concerning, in lines 189 and 190 the authors mention that they included 6 articles, not 7. This issue needs clarification.

- The authors included only three studies in the meta-analysis related to breastfeeding. In the limitations, please explain the limitations of conducting meta-analysis with low numbers of studies.

Discussion

- Lines 228 & 229, and 247 & 248: there is no need to repeat the objective of the study.

- Line 241: “a subgroup analysis was done by residence (both urban and rural versus rural)” It is not clear to me why the authors decided to explore this contrast. Why not to simply explore urban vs rural? Please clarify.

- Lines 249 to 251 and 265 to 258: there is no need to repeat the results of the study.

Conclusion

- “Based on the finding, the Ethiopian government should improve the existing family planning program for all women of childbearing age.” Given the considerable limitations of this meta-analysis, I believe the authors are overstating their conclusion. Please adjust in light of the limitations of the study.

Reviewer #2: General comments: This is an important review aimed at estimating the pooled prevalence of short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in. However, a number of issues need attention before acceptable for publication.

ABSTRACT:

Objectives: This is Ok.

Methodology: The authors should include the key words used in the search.

The authors should state the selection criteria.

The authors should state the outcome measures assessed.

The authors should state the subjects of the studies they included in the meta-analysis.

The authors should state which outcomes were analysed.

Main results: The authors should state the number of studies assessed, identified and how many were included in the meta-analysis. What were the results of heterogeneity across studies?

CONCLUSION

Why did the authors state that: “The practice of short birth spacing in Ethiopia was higher.?’

The authors should rephrase their conclusion because the practice of short birth spacing in Ethiopia cannot he said to be higher.

The authors should avoid 'slangs' in their writing like ‘didn’t’.

INTRODUCTION:

Although, this is well written; however, the introduction needs brushing up of language and beefing up the justification for the study.

MATERIALS AND METHODS

Why did the authors exclude relevant articles with full texts of which unavailable after two email contacts of the corresponding authors?

RESULTS

In table 1, why was the prevalence of the last three publications not included?

DISCUSSION

The authors must correct the typo errors and other errors in the manuscript. The authors need English language editor.

The authors should discuss the clinical implications of their study findings.

The authors should also discuss the strengths of their study.

**********

6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

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Reviewer #1: No

Reviewer #2: Yes: George Eleje

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

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PLoS One. 2021 Feb 3;16(2):e0246348. doi: 10.1371/journal.pone.0246348.r002

Author response to Decision Letter 0

30 Nov 2020

Mohammad Rifat Haider (MBBS, MHE, MPS, PhD)

Academic Editor, PLOS ONE

RE: Manuscript ID: PONE-D-20-19678 (Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis).

Dear Dr. Mohammad,

Thank you very much for your email and the comments/suggestions of the reviewers and academic editor. We have looked at the comments and have revised our paper accordingly. We hope our paper improved as a result of incorporating reviewer’s and academic editor’s comments and suggestions.

Please find for your kind consideration the following:

� A rebuttal letter that responds to each point raised by the academic editor and reviewer. The point by points responses are written in italic font style.

� A revised manuscript with track changes.

� A revised paper without tracked changes

� The point by points responses are written in italic font style.

While hoping that these changes would meet with your favourable consideration, we are happy to hear if there are more comments and suggestions. Please do not hesitate to let us know if you have any questions.

Yours Sincerely,

Yitayish Damtie

School of Public Health, Wollo University

Dessie, Ethiopia

Tel:+251943517982

E-mail: yitutile@gmail.com

Point by point response

Additional Editor Comments

Take care of the reviewers' comments. Put special emphasis on the English language and grammar.

� We have tried our best to improve it accordingly.

Journal Requirements:

When submitting your revision, we need you to address these additional requirements.

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and

https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

� We have tried to revise our manuscript according to PLOSONE formatting style.

� Thank you for remembering an important issue. As it is stated above, database search was carried out from April 1 up to May 30, 2020, and articles published from the 1990 to May 30, 2020 were included in the review but we have missed to write it in the manuscript.

3. At this time, we ask that you please provide the full search strategy and search terms for at least one database used as Supplementary Information.

� We have tried to attach the full search strategy as supplementary information.

� We have taken in to consideration and provide the funnel plots as a separate Figure in our

Manuscript.

Reviewer Comments to the Author

Reviewer#1:

� We have tried to improve it accordingly.

Abstract

methods: “and determinants of birth spacing in Ethiopia...” is not true. The researchers pre-specified the factors they explored. Please clarify.

� We acknowledged the problem and tried to correct it accordingly in the abstract.

Results: please describe the number of articles included in the review and in the meta-analyses.

� We have tried to describe it accordingly in the main document.

Conclusion: "The practice of short birth spacing in Ethiopia was higher." Please elaborate on this phrase.

� We have taken in to consideration and tried to improve it accordingly.

Introduction

Given the considerable number of factors associated with short birth spacing, it is not clear why the authors chose to explore only maternal education, contraceptive use, and duration of breastfeeding. Please clarify what criteria were used to choose the aforementioned factors.

� Thank you for your comment. As we have tried to justify it in the introduction, a wide range of maternal and service-related factors that affect short birth spacing were identified from the included studies. But, we only examine the association between short birth spacing and maternal education, contraceptive use, and duration of breast feeding since they were the most frequently mentioned factors and have controversial finding among the included studies. In addition to this, these three factors are clinically significant factors affecting short birth spacing. As a result, we have interested to test their statistical significance and settle the controversial finding they have across the included articles.

Methods

Line 95: “Grey literature was identified through the input of content experts.” It is not clear who these experts were and how they were selected and/or approached. Moreover, it is not clear how many studies the experts included and what criteria was used to select the studies.

� Thank you for your comment. Only one study with a case-control study design reporting determinants of birth spacing among women of reproductive age was identified from the input of the two content experts who are currently working in our organization and specialized in different areas of maternal and child health issues. They were selected based on their area of specialization and approached after explaining the objective of our study. The pre-set inclusion criteria’s were used to select the grey literature.

Lines 99 to 105: the authors should include the exact search they used in the different databases. A list of terms is not enough. Moreover, please consider uploading the search as an additional file as this will save space.

� We have tried to upload the exact search as an additional file accordingly.

Line 105: “This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist.” The PRISMA checklist is preferred for systematic reviews and meta-analysis of experimental studies. The MOOSE guideline is preferred for Meta-Analysis of Observational Studies in Epidemiology (doi:10.1001/jama.283.15.2008). Please refer to the MOOSE reporting guidelines and use them to report the findings of your article.

� The comment is accepted and addressed accordingly.

Inclusion criteria: the review is supposed to be focused only on studies exploring maternal education, contraceptive use, and duration of breastfeeding. However, this is not reflected in the inclusion criteria. Please clarify.

� Yes, definitely. The review focuses only on studies exploring maternal education, contraceptive use, and duration of breastfeeding. However, explaining it as an inclusion criteria would exclude many articles exploring only the prevalence of short birth spacing but not the factors that we have mentioned above.

Study setting: I suggest the authors to move this information to the introduction.

� The comment is accepted and addressed accordingly.

Outcome measurement: There will be many different definitions or cut-off points among the three factors that the authors wanted to explore in their systematic review. For example, the authors will find studies exploring duration of breastfeeding with cut-off points of 6, 8, 12, 18, and 24 months. It is not clear why the authors pre-specified their cut-off point to be 24 months. Moreover, it is not clear why the authors pre-specified their education contrast to be formal education vs no formal education, or contraceptive use yes vs no. Pre-specifying these contrasts would exclude many articles. This should be explained in the limitations section. Additionally, this information is not explained in the inclusion criteria. Please clarify.

� Yes, different cut-off points were used to define or categorize the three factors. But in our case, the cut-off points are not pre specified from the inception. Rather they are determined to be 24 months for the duration of breastfeeding, formal vs no formal education for maternal educational status and contraceptive use vs not use for contraceptive utilization after the review process since the majority of the included articles used these cut-off points to define the these factors. There is no need to explain the cut of points as an inclusion criteria as it exclude many articles.

Results

The authors reported high heterogeneity among the included studies. Why did the authors decide to conduct meta-analysis instead of providing a narrative synthesis of the results? Please clarify this sensitive issue.

� Thank you for raising an important issue. Yes it is undeniable that sever heterogeneity was reported among the included studies. The reason behind conducting meta-analysis instead of providing a narrative synthesis of the results in the presence of high heterogeneity is to achieve the ultimate aim of our study since the objective of our study is to determine the pooled prevalence of short birth spacing and its association with contraceptive use, educational status and duration of breastfeeding among reproductive age women. But, efforts like using random effect model, conducting subgroup analysis and meta-regression were considered to minimize the variation and to identify the source of heterogeneity among the included studies.

From the first paragraph of Results, it seems that the authors conducted a two-step screening phase. First, they screened the titles, and second, they screened the abstracts of the publications. In systematic reviews, however, titles and abstracts are evaluated together. I believe that screening the references in the way the authors did could introduce major biases in the review results. Please explain the rationale behind the two-step screening process.

� In the actual screening process, the title and the abstract of the articles were screened and evaluated together. You can confirm this by observing the PRISMA flow diagram (Fig1). But, to be specific, the number of articles excluded by the title and the abstract were narrated separately in the result section of the main document. We acknowledge the problem since it introduce wrong understanding for the readers and tried to revise it accordingly.

First paragraph of Results: the authors over explain the flow diagram of the articles screened/included. This information could be easily summarized in Figure 1.

� We have tried to minimize the narration accordingly.

In lines 181 to 184, the authors say that they included 7 studies in the meta-analysis. It is not clear why the authors included only these 7 studies from the original 9 included studies. More concerning, in lines 189 and 190 the authors mention that they included 6 articles, not 7. This issue needs clarification.

� No, we have not said that we included 7 studies in the meta-analysis. Rather we said, a total of 9 studies (Shallo and Gobena, Ejigu et al, Tsegaye et al, Ayane et al, Gebrehiwot et al, Yohannes et al, Hailu et al, Begna et al and Tessema et al) were included in this meta-analysis. Among these studies, 6 of them (Shallo and Gobena, Ejigu et al, Tsegaye et al, Ayane et al, Gebrehiwot et al and Yohannes et al) were included to estimate the pooled prevalence of short birth spacing and 6 among the 9 studies (Tsegaye et al, Ayane et al, Yohannes et al, Hailu et al, Begna et al and Tessema et al) were included to exam the association between maternal education, contraceptive use, and duration of breast feeding and short birth spacing.

The authors included only three studies in the meta-analysis related to breastfeeding. In the limitations, please explain the limitations of conducting meta-analysis with low numbers of studies.

� We acknowledge the problem and tried to explain the limitation in the main document.

Discussion

Lines 228 & 229, and 247 & 248: there is no need to repeat the objective of the study.

� We have tried to correct it accordingly in the main document.

Line 241: “a subgroup analysis was done by residence (both urban and rural versus rural)”. It is not clear to me why the authors decided to explore this contrast. Why not to simply explore urban vs rural? Please clarify.

� Thank you for your comment. This is based on the setting in which the studies were conducted. As we have stated it in the main document, six studies were included to estimate the pooled prevalence of short birth spacing. Among these studies, four of them considered both rural and urban women, two studies considered only rural women and no study considered only urban women. Due to this reason, subgroup analysis by residence was explored as both urban and rural vs rural.

Lines 249 to 251 and 265 to 258: there is no need to repeat the results of the study.

� We have tried to avoid the repetition accordingly

Conclusion

“Based on the finding, the Ethiopian government should improve the existing family planning program for all women of childbearing age.” Given the considerable limitations of this meta-analysis, I believe the authors are overstating their conclusion. Please adjust in light of the limitations of the study.

� We have tried to adjust it accordingly.

Reviewer#2:

ABSTRACT:

Objectives: This is ok.

� Thank you

Methodology: The authors should include the key words used in the search, should state the selection criteria, outcome measures assessed, the subjects of the studies they included in the meta-analysis and which outcomes were analyzed.

� Yes, all the things that you have mentioned above are very important and must be included in the methodology part. However, PLOSONE formatting style (300 words in the abstract section) limit us to incorporate all the aforementioned comments under the abstract section. As much as possible, we have tried our best to include some of them.

Main results: The authors should state the number of studies assessed, identified and how many were included in the meta-analysis.

� We have tried to address it accordingly.

What were the results of heterogeneity across studies?

� We have tried to include the result of heterogeneity as per your comment.

CONCLUSION: why did the authors state that: “the practice of short birth spacing in Ethiopia was higher.’ The authors should rephrase their conclusion because the practice of short birth spacing in Ethiopia cannot he said to be higher. The authors should avoid 'slangs' in their writing like ‘didn’t’.

� We acknowledge the problem and we have taken in to consideration.

INTRODUCTION

although, this is well written; however, the introduction needs brushing up of language and beefing up the justification for the study.

� We have tried to improve it accordingly.

MATERIALS AND METHODS

Why did the authors exclude relevant articles with full texts of which unavailable after two email contacts of the corresponding authors?

� We exclude articles with full texts of which unavailable after two email contacts of the corresponding authors because we couldn’t find relevant variables on the abstract section to achieve the prime objective of our study like sample size and the number of women with short birth spacing.

RESULTS

In table 1, why was the prevalence of the last three publications not included?

� Yes, definitely. The prevalence of the last three publications was not included in the table. Because, prevalence of short birth spacing could not be calculated the in the case of studies with a case-control and retrospective follow up study design. But, we include these three studies to examine the association between short birth spacing with maternal educational status, contraceptive use, and duration of breastfeeding.

DISCUSSION

The authors must correct the type errors and other errors in the manuscript. The authors need English language editor.

� We have tried to improve the type and grammatical errors accordingly.

The authors should discuss the clinical implications of their study findings.

� We have accepted the comment and tried to discuss the clinical implication of our finding in the discussion section of the main document.

The authors should also discuss the strengths of their study.

� Thank you for your comment. Discussing the strengths of this study is not as such important since our study shared all the strengths of the systematic review and meta-analysis.

Attachment

Submitted filename: Response to Reviewers.docx

Click here for additional data file.^{(33KB, docx)}

PLoS One. doi: 10.1371/journal.pone.0246348.r003

Decision Letter 1

Mohammad Rifat Haider

9 Dec 2020

PONE-D-20-19678R1

Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis:

PLOS ONE

Dear Dr. Damtie,

Please take care of the reviewer's comment.

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2. Is the manuscript technically sound, and do the data support the conclusions?

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Reviewer #2: Yes

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Reviewer #1: Yes

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Reviewer #2: No

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6. Review Comments to the Author

Reviewer #1: The authors have addressed all my comments. There are still a few English mistakes. For example, "Short birth spacing had been linked" (line 63) -> has been linked. "Data source and searching strategies" (line 107) -> search strategy. I suggest the authors use a professional editing service to fine tune the manuscript.

Reviewer #2: The authors have addressed the issues adequately. This is a systematic review aimed at estimating the pooled prevalence of short birth spacing and its association with contraceptive use, educational status, and duration of breastfeeding among

reproductive-age women in Ethiopia.

Title: This is OK.

Regarding the English language, the authors have endeavored to work on it.

**********

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Reviewer #1: Yes: Juan Pimentel

Reviewer #2: Yes: George Eleje

PLoS One. 2021 Feb 3;16(2):e0246348. doi: 10.1371/journal.pone.0246348.r004

Author response to Decision Letter 1

22 Dec 2020

Mohammad Rifat Haider (MBBS, MHE, MPS, PhD)

Academic Editor, PLOS ONE

RE-2: Manuscript ID: PONE-D-20-19678R1 (Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis).

Dear Dr. Mohammad,

Please find for your kind consideration the following:

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Yours Sincerely,

Yitayish Damtie

School of Public Health, Wollo University

Dessie, Ethiopia

Tel:+251943517982

E-mail: yitutile@gmail.com

Point by point response

Additional Editor Comments

Please take care of the reviewer's comment.

� Thank you for your comment and suggestion, we have tried to incorporate all the reviewers comment in our revised manuscript.

Reviewer’s comments

Reviewer #1:

The authors have addressed all my comments. There are still a few English mistakes. For example, "Short birth spacing had been linked" (line 63) -> has been linked. "Data source and searching strategies" (line 107) -> search strategy. I suggest the authors use a professional editing service to fine tune the manuscript.

� Thank you for your constructive comments. We acknowledge the problem and we have tried to change “Short birth spacing had been linked" to has been linked and Data source and searching strategies" to search strategy on line number 66 and 102 of our revised manuscript respectively.

� We have tried our best to address the English mistakes in our manuscript

Reviewer #2:

The authors have addressed the issues adequately. This is a systematic review aimed at estimating the pooled prevalence of short birth spacing and its association with contraceptive use educational status and duration of breastfeeding among reproductive-age women in Ethiopia.

Title: This is ok

� Thank you in advance.

Regarding the English language, the authors have endeavored to work on it.

� Thank you for your comment. Efforts were made to address all the English mistakes and grammatical errors in our revised manuscript.

Attachment

Submitted filename: Response to Reviewers.docx

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PLoS One. doi: 10.1371/journal.pone.0246348.r005

Decision Letter 2

Mohammad Rifat Haider

18 Jan 2021

Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis:

PONE-D-20-19678R2

Dear Dr. Damtie,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

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Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #2: Yes

**********

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Reviewer #2: Yes

**********

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**********

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PLoS One. doi: 10.1371/journal.pone.0246348.r006

Acceptance letter

Mohammad Rifat Haider

21 Jan 2021

PONE-D-20-19678R2

Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. a systematic review and meta-analysis

Dear Dr. Damtie:

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Kind regards,

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on behalf of

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Data Availability Statement

All relevant data are within the manuscript and its Supporting Information files.

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PERMALINK

Short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia. A systematic review and meta-analysis

Yitayish Damtie

Bereket Kefale

Melaku Yalew

Mastewal Arefaynie

Bezawit Adane

Roles

Abstract

Background

Methods

Results

Conclusions

Introduction

Materials and methods

Search strategy

Inclusion and exclusion criteria

Outcome measurement

Data extraction

Quality assessment

Data analysis

Results

Study selection

Fig 1. PRISMA flow diagram describes the selection of studies for a systematic review and meta-analysis of short birth spacing and its association with maternal educational status, contraceptive use, and duration of breastfeeding in Ethiopia, 2020.

Characteristics of the included studies

Table 1. Descriptive summary of nine studies included in the meta-analysis of short birth spacing and associated factors among women of childbearing age in Ethiopia, 2020.

Prevalence of short birth spacing in Ethiopia

Fig 2. Forest plot of the pooled prevalence of short birth spacing among reproductive-age women in Ethiopia, 2020.

Table 2. Univariate meta-regression analysis to determine factors related to the heterogeneity of the prevalence of short birth spacing in Ethiopia, 2020.

Fig 3. Funnel plot with 95% confidence limits of the pooled prevalence of short birth spacing among reproductive-age women in Ethiopia, 2020.

Subgroup analysis

Fig 4. Forest plot of the pooled prevalence of short birth spacing by the area of residence (rural versus both urban and rural) in Ethiopia, 2020.

Table 3. Subgroup prevalence of short birth spacing in Ethiopia, 2020 (n = 6).

Factors associated with short birth spacing

Fig 5. The pooled odds ratio of the association between contraceptive use and short birth spacing in Ethiopia, 2020.

Fig 6. Funnel plot with 95% confidence limits of the pooled odds ratio of contraceptive use among women in Ethiopia, 2020.

Fig 7. The pooled odds ratio of the association between the duration of breastfeeding and short birth spacing in Ethiopia, 2020.

Fig 8. Funnel plot with 95% confidence limits of the pooled odds ratio of the duration of breastfeeding among women in Ethiopia, 2020.

Fig 9. The pooled odds ratio of the association between maternal educational status and short birth spacing in Ethiopia, 2020.

Fig 10. Funnel plot with 95% confidence limits of the pooled odds ratio of maternal educational status in Ethiopia, 2020.

Discussion

Limitations of the study

Conclusions

Supporting information

Acknowledgments

List of abbreviations

Data Availability

Funding Statement

References

Decision Letter 0

Mohammad Rifat Haider

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Author response to Decision Letter 0

Decision Letter 1

Mohammad Rifat Haider

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Author response to Decision Letter 1

Decision Letter 2

Mohammad Rifat Haider

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Acceptance letter

Mohammad Rifat Haider

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Associated Data

Supplementary Materials

Data Availability Statement

ACTIONS

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