Safe child feces disposal practices and its association with reported diarrhea in low-income and middle-income countries: A systematic review and meta-analysis protocol

Introduction: In household environments, the improper handling of children's feces can be a signicant contaminant, raising a high risk of baby exposure. Several studies done on the magnitude of safe disposal of child feces and its association with reported childhood diarrhea have varied outcomes and no tries have been made to systematically review this. Therefore, a systematic review is necessary to provide an exhaustive summary of the current evidence. Thus, the objective of this a systematic review and meta-analysis will be to pool out the available evidence on the magnitude of safe child feces disposal practices and its association with reported childhood diarrhea in low-income and middle-income countries. Methods: In order to nd applicable literature for this study, PubMed, Science Direct, the Cochrane Library collection and Ovid Medline will be searched. In addition, it can search for Google Search Engine, Google Scholar, and references from other studies.The primary outcome of interest will be the magnitude of safe child feces disposal practices and the secondary outcome will be its association with reported diarrhea. Observational studies (cross-sectional studies, case-control studies, and cohort studies) written in English, from January 2000 onwards will be included. The selected studies will be critically appraised by two independent reviewers using an appropriate tool. The pooled magnitude of safe child feces disposal practices and its association with reported childhood diarrhea will be analyzed using Stata version 16. Heterogeneity will be assessed using the chi-square test (Q-test) statistics and inverse variance index (I 2 ). Forest plots will be used to present the combined estimate with 95% CI. A funnel plot and Egger’s test of small study bias will be used to assess publication bias. Discussion: This systematic review will identify the evidence available on the magnitude of safe child feces disposal practices and its association with reported diarrhea. The ndings from this study will be made publicly available in a repository and published in a peer-reviewed journal. The ndings from this study will also provide directions for future research and public health professionals with an understanding of the importance of safe child feces disposal practices to preventing childhood diarrhea in the community.

child feces disposal practices and the secondary outcome will be its association with reported diarrhea. Observational studies (cross-sectional studies, case-control studies, and cohort studies) written in English, from January 2000 onwards will be included. The selected studies will be critically appraised by two independent reviewers using an appropriate tool. The pooled magnitude of safe child feces disposal practices and its association with reported childhood diarrhea will be analyzed using Stata version 16.
Heterogeneity will be assessed using the chi-square test (Q-test) statistics and inverse variance index (I 2 ).
Forest plots will be used to present the combined estimate with 95% CI. A funnel plot and Egger's test of small study bias will be used to assess publication bias.
Discussion: This systematic review will identify the evidence available on the magnitude of safe child feces disposal practices and its association with reported diarrhea. The ndings from this study will be made publicly available in a repository and published in a peer-reviewed journal. The ndings from this study will also provide directions for future research and public health professionals with an understanding of the importance of safe child feces disposal practices to preventing childhood diarrhea in the community. Systematic review registration number: PROSPERO CRD42020189034 Background Lack of sanitation services and poor hygiene habits lead millions of the poorest people in the world to die each year from preventable diseases [1]. Many countries are challenged in providing adequate sanitation for their entire population and leaving people at risk [2]. It is estimated that insu cient sanitation causes 432,000 annual diarrhea deaths and is a major factor in many neglected tropical diseases, including intestinal worms, schistosomiasis, and trachoma, as well as contributing to malnutrition [3]. The study revealed about 2 billion people living in rural areas are adversely affected by the lack of adequate water supply and by open defecation [4]. A study done by Prüss-Üstünet al. showed that 5.48% of all deaths and 7.67% of the disability-adjusted life years (DALYs) lost in low-income and middle-income countries are due to poor WASH-related diarrheal diseases and parasite infestations [5].
There are now nearly 2.0 billion people without basic sanitation services, such as toilets or latrines. Of those, 673 million still defecate outdoors, for instance in street gutters, behind bushes, or in open bodies of water [3]. In Ethiopia, access to improved sanitation facilities is also very limited in rural areas where the majority of households defecate in the bush or open elds [6]. Without proper sanitation facilities, waste from infected individuals can contaminate a community's land and water, increasing the risk of infection for other individuals [3]. Studies conducted in an urban slum of Nairobi, Kenya, and rural Odisha, India, found that fecal contamination from young children was pervasive in the domestic environment both inside and outside the household, with young children's feces being a more common source of human fecal contamination in households than older children/adults feces [7,8].
The unsafe disposal of children's feces may be an important contaminant in household environments, posing a high risk of exposure to infants. Poor sanitation can result in substantial health impacts in children, including a higher prevalence of diarrhea, intestinal worms, enteropathy, malnutrition, stunting, and death. A study reported from Indonesia showed that the odds of diarrhea are signi cantly greater in households practicing unsafe disposal of child feces than those practicing safe disposal [9]. Similarly, another study nding reported that unsafe disposal of feces increased the risk of diarrhea by 23%. It is also a risk factor for soil-transmitted helminthes infections, e.g., hookworm, ascariasis, and trichuriasis, which cause environmental diseases that are characterized by poor nutrient absorption in the gut [6,10].
Previously conducted studies done on the association between unsafe disposal of child feces and reported diarrhea to have inconsistent outcomes and no tries have been made to systematically review this. Considering this, the present study aims to attract more attention to the necessity of safe child feces disposal practices and to generate evidence that can reassure changes in public policy that can encourage to address public health problems of diarrhea.

Objective
The objective of this systematic review and meta-analysis will be to pool out the available evidence on the magnitude of safe child feces disposal practices and its association with reported childhood diarrhea in low-income and middle-income countries. The research question of this review are: What is the magnitude of safe child feces disposal practices in low-and middle-income countries?
Is there an association between safe child feces disposal practices and reported diarrhea in low-and middle-income countries?

Study design and Protocol
The present study protocol is being reported following the reporting guidance provided in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) statement [11] (Additional le 1) and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline will be followed during the systematic review [12]. The four phases that were drawn from the PRISMA ow chart will be documented in the results to show the study selection process from initially identi ed records to nally included studies [13]. The present protocol has been registered within the PROSPERO database (registration ID: CRD42020189034). Any amendments made to this protocol will be outlined and reported in the nal manuscript.

Inclusion criteria
Participants: Our population of interest will be children aged less than 5 years old. So, the systematic review will also consider studies that include participants below the age of 5 years to examined child feces disposal practices and its association with reported diarrhea, regardless of sex, ethnicity and socio-economic status.
Outcome: magnitude of safe child feces disposal practices and/or its association with reported diarrhea.
Study design and setting: We will include published observational studies (cross-sectional studies, case-control studies, and cohort studies) that examined child feces disposal practices and its association with reported diarrhea. We will include studies conducted in low-and middle-income countries.
Language and years of publication: Only studies published in English, from January 2000 onwards will be included.

Exclusion criteria
We will not consider previously published systematic reviews and qualitative studies. Articles which were not able to be accessed for full article text after at least two email contact attempts with the primary authors were also excluded due to inability to assess the quality of articles in the absence of full text Information sources and search strategy Electronic databases such as PubMed, Science Direct, Cochrane Library databases, and Ovid Medline will be searched to identify relevant literature for this review. Additionally, we will hand search Google search engine, Google Scholar, and references of other studies. The literature search will be carried out by the rst author in October 2020. The search strategy will be limited to studies published in English language literature. We will apply Medical Subject Headings terms from PubMed, and combined keywords to identify studies in the databases. We will use keywords terms and combinations with MESH terms as described below. A full search strategy for PubMed is detailed in Table 1.

Study selection process
The searched results will be export to Mendeley Desktop reference management software version 1.19.5 (Mendeley Ltd., Elsevier, Netherlands) and then duplicate excluded. The screening of studies will be conducted by two independent review authors. The articles found by searches in databases will be evaluated for inclusion at three levels, i.e., by title, then by abstract, and nally by full-text. The full-text of selected studies will be retrieved and assessed in detail against the inclusion criteria. Discrepancies will be discussed between reviewers and re ne inclusion criteria. For the screening of articles at the full-text level, rejection of an article will be decided by the review team upon the suggestion of the rst reader. The details regarding the nal decision of the inclusion of articles will be clari ed and archived in a database. In case of uncertainty in the decision to include or exclude an article, the reviewer will include this article for the next level of screening. The documents without abstracts will be screened at the full-text level. A list of articles excluded at the full-text level will be provided in the systematic review, accompanied by reasons for exclusion.

Data extraction
The adapted JBI data extraction form will be used to extract the characteristics of the studies and status of child feces disposal practices and the odds ratios that showed the association of unsafe disposal of child feces and reported diarrhea. A standardized excel sheet will be created and information from the standardized review forms will be transferred to be readily available for the systematic review. For each study, authors' name and year of publication, country of origin and set of included studies, type of study included, sample size, description of child feces disposal practices, and results of included studies will be extracted by two reviewers. Any disagreements that arise between the reviewers will be resolved through discussion or with a third reviewer.

Outcome of interest
The primary outcome of this review will be pooled magnitude of safe disposal of child feces and the secondary outcome of this study will be the estimate of the association of safe child feces disposal practices and reported diarrhea. Child feces disposal was de ned based on the WHO/ UNICEF JMP for water supply & Sanitation de nition [14] as safe disposal if households responded by saying collected and disposed of in a latrine or buried it, and as unsafe disposal, if they said put into a drain or ditch, thrown into the garbage or left in the open. Whereas diarrhea de ned as three or more loose or watery stools during 24 hours or any loose stool that contained blood or mucus.

Evaluation of study quality
The methodological quality of all studies that meet the selection criteria will be evaluated independently by two authors using the Joanna Briggs Institute (JBI) Critical Appraisal tools [15]. Each study will be assessed individually and independently by the two reviewers, both at the outcome and study level to generate an overall risk of bias score. The reviewers will assign each study as critical, serious, moderate, or low risk of bias via the judgment of the gathered information. If there is limited information, then the risk of bias will be categorized as "no information" or we will contact the corresponding authors for complete information and clarity of primary studies. The rating for each bias criterion of the two authors will then compare. Disagreements between the two authors on individual bias criteria will be identi ed and discussed in an attempt to reach a consensus.

Data synthesis and statistical analysis
The individual studies will be concisely described using a summary table. The summary table particularly describes the characteristics of the included studies and the main ndings. Based on the summary table, we will conduct a narrative synthesis rst to describe the characteristics of the included studies and the main ndings. Then, meta-analysis will be conducted using a random effect or xed effect when at least three studies are comparable in design and protocol using Stata version 16 (College Station, TX 77845, USA). The overall magnitude of child feces disposal practices and its 95% CI will be calculated from standard error (SE) and magnitude of child feces disposal practices of each included study. For studies that did not present a SE, it will be calculated using the formula; SE = √ (p× (1−p)/n). The calculated SE and magnitude of each study will then be entered into Stata software to calculate the overall prevalence and its 95% CI. Similarly, the association between child feces disposal practices and reported diarrhea will be summarized using statistical estimates of effect size, odds ratio (OR), and 95% CI of the study factors. We will perform subgroup analyses according to the possible characteristics of the studies and the quality of the study included. A sensitivity analysis will be repeated after excluding one study to observe the impact of the individual study on the pooled estimate.
Heterogeneity will be assessed statistically using a chi-square test (Q-test) for statistics and inverse variance index (I 2 ) [16]. I 2 values will be classi ed as follows: no relevant heterogeneity (0-25%), moderate heterogeneity (25-50%), and signi cant heterogeneity. The data will be considered homogeneous if I 2 ≤50%. Fixed effects models will be used to produce summary ORs and 95% CIs where heterogeneity did not exist. If statistical heterogeneity did exist, then random-effects models will be applied. Forest plots will be generated to present the pooled estimates with 95% CI. A funnel plot and Egger's test of publication bias will be used to assess publication bias. Symmetrical funnel plot as well as insigni cant Egger's test will be taken as evidence for no serious publication bias. Trim and ll techniques will be considered for substantial publication bias.

Discussion
This systematic review and meta-analysis would thoroughly analyze and incorporate the existing data on the extent of the safe disposal practices of child feces and its association with reported diarrhea.
Information on the magnitude and association between the safe disposal practices of child feces and reported diarrhea will be compiled and outlined in this study. The review will be reported according to the PRISMA guidelines [13] and will be made publicly available in a repository and published in a peerreviewed journal. The results of this analysis will provide recommendations on the signi cance of safe child feces disposal practices in reducing childhood diarrhea in the population for potential research and public health practitioners to consider. The limitation of this study is that only quantitative observational research conducted in the English language will be considered. Availability of data and material: All the data relevant to the study are included in the article or uploaded as supplementary information Competing interests: None declared.
Funding: This research received no speci c grant from any funding agency in the public, commercial, or not-for-pro t sectors.
Authors' contributions: NES contributed to developing and drafted the protocol. NES, BKO, and DBG contributed to the supervised the development of the protocol and revise the protocol. All the authors have approved the current protocol version.