sex with boy and girl

Oleh elonmisk Maret 10, 2021 Posting Komentar

Young amateur boy and girl take bed sex seriously - Pornjam.comInformation for Open AccessHelp and information Stay up to dateRegistered in England & Wales No. 3099067 5 Howick Place Silencio London SW1P 1WGWe use cookies to improve your web site experience. To know our use of cookies and how you can manage the cookie settings, see our To close this message, you are accepting our use of cookies.

Log in using your username and password Main menu Log in using your username and password You are hereArticle Text Summary Background Excessive male morbidity and mortality are well recognized in neonatal medicine and child health. In contrast, in the context of global nutrition, girls are often at greater risk of undernutrition. We advocate to explore evidence of any difference between men and women in child malnutrition using anthropometric definitions of cases and the reasons for the differences observed. Methods We search: Medline, Embase, Global Health, Popline and Cochrane databases without time limits applied. Eligible studies focused on children from 0 to 59 months affected by malnutrition where sex was reported. In meta-analysis, specific estimates of undernutrition were examined separately to waste, nurture and underweight using a model of random effects. Results 74 studies were identified: 44/74 studies were included in meta-analysis. In 20 cases where waste was examined, boys were more likely to be wasted than girls (with OR 1,26, 95% CI, 1.13-1, 40). 38 examined the stunt: boys were more likely to be stunned than girls (with OR 1,29 CI 95% 1.22 to 1.37). 23 explored under weight: boys were more likely to be underweight than girls (with an RW 1.14, 95% CI 1,02 to 1.26). There were limited evidence that the female advantage, indicated by a lower risk of stunting and low-weight, was weaker in South Asia than in other parts of the world. 43/74 (58%) studies discussed possible reasons for differences between boys and girls; 10/74 (14%) cited studies with similar results without further discussion; 21/74 (28%) did not have a gender difference. 6/43 studies (14 per cent) postulated biological causes, 21/43 (49%) social causes and 16/43 (37%) to a combination. Conclusion Our review indicates that malnutrition in children under 5 is more likely to affect boys than girls, although the magnitude of these differences varies and is more pronounced in some contexts than others. Future research should continue to explore the reasons for such differences and implications for nutrition policy and practice. This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0), which allows others to copy, redistribute, remix, transform and build on this work for any purpose, provided that the original work is correctly cited, a link to the license is given, and an indication of whether changes were made. See: .Altmetric.com Statisticians Key Issues What is already known? Malnutrition (waste, lightheadedness and low weight) is a public health problem that affects millions of children under 5 years of age worldwide. While neonatal morbidity and mortality and the highest infant mortality for children are well described, little attention has been paid to sexual differences in the area of malnutrition because girls are very often disadvantaged by children. What are the new findings? In most of the studied environments, malnutrition is more common among boys than girls, although the scope of these differences varies and is invested in some contexts. It has been proposed that both biological and social mechanisms be responsible for the observed differences, as well as a combination of both. Key issues What do new findings imply? Increased awareness of actual sexual differences in the field of nutrition is needed. While gender-specific data are routinely analysed and reported in nutrition studies, it should be used in nutrition programming to better identify and understand existing differences. The analysis should assess whether the gender balance in programme admissions reflects the burden of malnutrition among the population. It is necessary to continue to investigate both the mechanisms behind it and the reasons for it lead to gender and gender differences in malnutrition and its implications for nutrition policy and practice. Better epidemiological understanding is a priority, as is the work to explore its consequent effects on morbidity and mortality. IntroductionDisintrition is a serious public health problem that affects millions of children around the world. Recent estimates indicate that stunt (low age) affects approximately 149 million children, with consequences for growth and cognitive development. Waste (low weight per length), a consequence that threatens the lives of acute nutrient deficits and/or diseases affects more than 49 million children worldwide; 17 million of them are severely wasted. However, these numbers are based on prevalence estimates that mean that real numbers can be considerably higher when the incidence is taken into account. Sex (refer to biological attributes) and gender (refer to socially constructed roles, behaviours and identities) are important considerations in the field of public health and are given different importance in different academic and professional fields. Despite considerable research on the differences in child sex in neonatal and child health, different disciplines often have surprisingly contrary views on the relative vulnerability of boys and women. In the neonatal and child health communities, the excess of male morbidity and mortality is almost universal and is widely recognized. Children are known to be more vulnerable than girls, from the point of view of conception. Common conditions in childhood, such as lower respiratory infections, diarrhoeal diseases, malaria and premature childbirth, are more common in boys than in girls, except measles, cough and tuberculosis. They are not only causes of death, but also of weight loss, growth falterization or severe malnutrition among young children. The differences between boys and girls have not been explored in detail in the field of nutrition, but girls are often considered more disadvantaged and vulnerable from a gender perspective. The way in which the underlying biological mechanisms related to gender-related sexual and social differences are translated into the risk of anthropometric deficits and related morbidity and mortality in the field of nutrition remains under study. The practical implications of these differences are also to be determined. In terms of growth and nutritional status, sexual differences have long been recognized and have been reflected through growth charts targeting individual sexes. On average, children are slightly heavier and longer at birth and throughout childhood compared to girls, and more detailed studies have shown that the extra average weight of children is mainly lean mass, while fat mass is more similar among sexes. To assess growth and nutritional status, gross anthropometric data are conventionally converted into indexes (e.g. weight by age; weight by length, length by age) and expressed in comparison with reference populations as z cores (DSD points, for which +1 and −1 z-scores are one of the SDs above and below the population's medium of reference, respectively). The data published by WHO in 2006 represent a 'golden standard' of how children should grow and develop from a globally representative reference population of healthy and breast-feeding children. In the construction of growth standards, data for boys and girls were analyzed separately and, therefore, the resulting growth lists should already take into account sexual differences. What has received little attention to date is whether gender differences reappear when the z-scores of the healthy reference range are moved, which would indicate gender differences in susceptibility to malnutrition. The objectives of this review were to systematically review gender differences in undernutrition of children under 5 years of age, review evidence of differences between men and women in child malnutrition and document the reasons for the observed differences. MethodsThis systematic review was carried out following the guidelines Preferent of Reporting Items for Systematic reviews and Meta-Analyses (PRISMA). A protocol for the review, including inclusion and exclusion criteria, was defined and shared among the authors for consensus. The protocol was then registered with (CRD42018094818). The scope of this initial protocol was broad, but as the examination and heterogeneity of the identified studies progressed, we made it increasingly clear, we made the decision to divide our work into two parts: the first (this study) focuses on the prevalence and recognition of gender-related differences; and the second, which will focus on the physiological and sociological mechanisms that can take into account the identified differences. Search strategy Our search strategy captured the concepts of malnutrition, sex and gender. (5708) sickness (39279) in the case of malnutrition/fetal disease (in English)) Studies were identified by searching the Medline database using the terms mentioned above that were then adapted to the Embase, Global Health, Popline and Cochrane databases. No limits were applied for the year of publication in order to capture historical publications on the subject. The studies were limited to those that included terms for children, men, women, sexes or sexes in the title or abstract, with the objective of filtering through the large body of literature that exists for studies of malnutrition and capture that focus directly on sex and/or gender in the context of malnutrition or those that were disaggregated and reported on the main results. According to PRISMA's recommendations, the search strategy was revised by a librarian. Eligibility criteriaThe studies were included in the review if they met the following criteria: human studies, age range from 0 to 59 months, male and female participants, results related to the prevalence or determinants of malnutrition, and related morbidity and mortality. Studies could be included in meta-analysis if they presented sex-disaggregated data for both the general sample and the result of interest (wasting, lightning, low weight) or relevant RWs. Studies of children over 59 months, non-English, animal studies and studies on overweight/obesity and micronutrient deficiencies were excluded. Both peer-reviewed and gray literature were selected. In studies that included data for children under 59 months and older, when possible, we extract data for children Data extraction All records identified through search were imported into EndNote (EndNote V.X8, Clarivate Analytics). The duplicates were identified and eliminated. The initial projection was made by reading titles and summaries to identify and eliminate studies that clearly did not fit into our field. A detailed review of the full text of all remaining results was undertaken to determine the inclusion and exclusion criteria. When it was unclear how to classify an article, this was resolved through discussion and consensus with two or more authors. Prior to completion, a data extraction template was tested on a small number of items. Data on study characteristics and interest results were extracted. These included objectives and types of studies, sample size, prevalence, and male/female RW for malnutrition, and explanations offered for any identified difference. Analysis Due to variations in the type of paper and study design, the analysis was performed in two parts: a systematic qualitative review followed by a meta-analysis. We perform random effects metaanalysis to group estimates of studies that included a measurement of the prevalence of malnutrition, or that assessed risks and determinants of malnutrition, and sex-strateged results. Lost counts, denominators and effects estimates such as RW, relative risk and associated CIs were calculated from other information provided when possible. Studies that presented only adjusted RWs or risk ratios were excluded, as studies would likely fit different factors and that those adjusted effects estimates were not directly comparable. The specific estimates of malnutrition were kept separately to waste, nurture and sub-weight using a random effect model. The analysis was also stratified by age and country. The effects are presented as ORs and 95% CI. A meta-regression was carried out to determine whether the specific factors in the study could explain the heterogeneity of the impact estimates in the studies. Statistical analysis was performed using Stata V.15.1 (StataCorp 2017, Stata Statistical Software, College Station, Texas, USA). In all studies conducted prior to 2006, references had been made to the growth of the National Health Statistics Centre (NCHS). In all post--2006 studies that were included, the WHO growth standards (2006) were used for waste, eaguide and low weight, measured through the SD of the z-score averages. The waste was defined by weight at height z-score Risk of the bias assessment We adapted the quality evaluation tools of the study of the National Heart, Pulmon and Blood for observational cohort and cross-sectional studies to evaluate the quality of the studies, and applied it to studies identified for metaanalysis. Using this tool, we evaluate data sources, the presentation of objectives and target populations of a study, the suitability of anthropometric methods and the presentation of results. We adapted the tool to assess whether studies recognized sexual differences in the outcome debate. Participation of the patient and the public The design of this review meant that it was not appropriate or possible to involve patients or the public in the design, or to perform, or report, or to disclose plans of our research. ResultsSelection of studies The study flow diagram summarizes our study identification process. The final search for Embase, Global Health, Popline and Cochrane databases conducted in March 2020 identified 34,270 studies, including both peer-reviewed and gray literature. In addition, 21 studies were found from other sources. After the elimination of duplicates, 22 357 studies remained. The initial projection excluded 21 925 studies, as they were not related to our review questions. The full texts of the remaining 432 studies were reviewed in detail to assess admissibility. At this stage, 358 other studies were discarded, as they did not meet the inclusion criteria, mainly because sex or gender were not mentioned in relation to malnutrition. As a result, seventy-four studies were included in qualitative synthesis. Finally, we reviewed the 74 studies for inclusion in meta-analysis and excluded 30 on the insufficiently disaggregated database (which prevented the calculation of RWs). Thus, 44 studies were included in meta-analysis. PRISMA Flow Diagram. PICO, Population, Intervention, Comparison, Result; PRISMA, Preferential Information Systemic Review and Meta-Analyses. Characteristics of the study shows the characteristics of each of the studies included in the examination. The studies selected for the review varied widely in terms of objectives and study design. Many were observational, evaluated the prevalence of malnutrition and associated risk factors, and many of them included secondary data analysis. Results, both primary and secondary, also varied widely. Studies took place in more than 30 countries (some covered several countries). The surveys were distributed in Central Africa (3/74) East Africa (33/74), East Asia (1/74), North Africa (1/74), Oceania (1/74), South America (2/74), South Asia (10/74), South-East Asia (9/74), South-West Pacific (1/74), West Africa (8/74) and several countries (5/74). Study characteristics When the sample size was clearly indicated, the studies included involved 361 736 participants. No distribution of boys and girls was provided for all studies, but, where they were, the results showed a total of 1 489 586 (44.3 per cent) girls and 1 531 859 (45.6 per cent) boys. Age inclusion criteria involved a combination of studies covering all children from 0 to 59 months, with others focusing on subsets of these children. Meta-analysis We identified 74 studies that had measured malnutrition in the form of waste, light and low weight and reviewed them for inclusion in meta-analysis. Among the 44 studies were extractable data, totally sex-disaggregated and therefore entitled to inclusion, 41 of them were cross-cutting and 3 were longitudinal (in which case the most recent prevalence data were used). The results of the analysis are presented on the forest plots in .Experience tests that show the probability rates of waste, lightning and low weight in boys compared to girls. Combined analysis by result Twenty studies were included in the combined waste analysis. In 17 of the 20 studies, waste was more common in boys than girls, with evidence of difference in 11/17 of the studies. In the remaining three studies, waste was more frequent in girls than in boys, with a significant difference in 1/3 of the studies. The combined results of individual studies to waste showed that children were 26 per cent more likely to be wasted than girls (with OR 1.26, 95% CI 1.13-1.40, three studies were included in the combined analysis of stunting. In 32 of the 38 studies, stunt was more frequent in boys than in girls, with evidence of difference in 28/32 of the studies. In the remaining six studies, the stunt was more frequent in girls than in boys, with a significant difference in 3/6 of the studies. The combined results for the stunt showed that boys were 29% more likely to be stunned than girls (with a RW 1,29 BCI board of 95% 1.22 to 1.37, pTwenty-three studies were included in the combined low-weight analysis. In 18 of the 23 studies, the lower weight was more common in boys than in girls, with evidence of difference in 10/18 of the studies. In the remaining five studies, girls were more likely to be underweight than boys, with a significant difference in 4/5 of the studies. The results of the pool for the low weight showed that children were 14% more likely to be underweight than girls (OR 1.14, 95% CI 1.02 to 1.26, pPooled analysis by regionWhen organized by region, the chances of children being undernourished were almost always higher than girls for waste, delay and low weight. To waste, the odds were higher for boys than for girls in all regions. For stunting, the odds were greater for boys than for girls in all regions except in South Asia (around OR 0.88, 95% CI 0.62 to 1.26, p=0.492), where there was no difference by sex. For children underweight, the probabilities were higher for boys than for girls in all regions except in Central America (OR 0.53, 95% CI 0.40 to 0.72 children undernourished compared to girls by regions and age groups Group Analysis by ageWhen organized by age groups, the probabilities to waste, nurture or lose weight are higher for girls than boys. The results of the analysis are presented in . We repeat the relative risk analysis and find that the results were consistent with the results for ORs. There was strong evidence of heterogeneity of effect between studies (awakening I2=81.6%, pRisk bias within studies The quality assessment can be seen in . All the studies presented seem to be of acceptable quality. It should be noted, however, that several studies were excluded prior to this process due to the absence of adequate data. The main differences in quality were in the area that assessed whether sexual differences were recognized and explored (see the qualitative synthesis section). Sesgo Assessment RiskQualified summary Setenta and four studies reported on results related to malnutrition, waste and low weight. As a result, 38/74 studies reported waste as a result of 31/38 (81%) reporting higher prevalence of waste in children, 6/38 (16 per cent) reporting higher prevalence of waste in girls, 1/38 (3 per cent) without reporting a difference in the prevalence of waste among boys and girls. Sixty-seven out of 74 studies reported the delay in the process as a result. Fifty-four out of 67 (81%) reported a higher prevalence of children ' s delays and 13/67 (19%) reported a higher prevalence of girls ' delays. Thirty-five out of 74 studies reported the low weight as a result. Twenty-five (80%) reported a higher prevalence of low weight in boys, 7/35 (20%) reported a higher prevalence of low weight in girls. We review the discussion sections of the reports to see whether those conclusions were explicitly recognized and whether explanations were provided. Forty-three of 74 (58%) of the studies discussed the findings, 10/74 (14%) studies cited articles with similar findings but did not speculate on the causes of these differences and 21/74 (28%) of the studies did not discuss the findings related to sexual differences at all. Among the study reports that provided explanations for sexual differences, the reasons varied widely and were often conjectureal. We codify explanations as biological (6/43; 14%), social (21/43; 49%) or a combination of the two (16/43; 37%). Biological reasons vary from a simple declaration of biological differences to a more detailed exploration of sexual differences in the immune and endocrine system between children. The social reasons given vary widely and are almost entirely conjectureal, with exceptions identified by the regression analysis related to the preference of children and related to the order of brother and sex. Other social reasons include gender dynamics, preferential feeding practices for boys and girls, child feeding practices and young children, such as early weaning for child and child behaviors, whereby girls can stay closer to the home and have more access to cooked food, while boys play outside and in turn eat less while spending more energy. Discussion This review offers a systematic look at sexual differences in a wide geographical area. Studies included in meta-analysis show that children from 0 to 59 months are much more likely to be wasted, stunned and underweight using anthropometric definitions of cases than girls. This indicates sexual differences in susceptibility to malnutrition. The reasons currently envisaged for these differences vary and are often speculative rather than being informed by direct evidence. When stratified by region, the results also showed that children are more likely to be wasted, stunned or underweight than girls. However, there were some exceptions in which RWs were reduced or reversed for children with regard to malnutrition, in East Africa, Central America, South and South-East Asia. The differences in Central America were based only on a study, with a limited sample size and therefore should be interpreted with caution. Our analysis potentially masks some of the complexities of regional variations in sexual differences, particularly in South and South-East Asia, as many studies in these regions did not qualify for inclusion in meta-analysis due to insufficient data. These differences may be underestimated or overestimated. By reviewing individual studies identified in the main search, the results of this region are inconsistent and often conflictive compared to those from other regions of the world, such as Africa, which show a more consistent pattern of male disadvantage, a resonant finding with other studies. However, inconsistencies in the conclusions of some parts of South and South-East Asia may be explained in part by well-described social preferences for men and justify further investigation. These differences have also been described in relation to the mortality of children under 5 years of age, with an excess of female infant mortality due to certain diseases, and according to the socio-economic situation, birth order and family composition. These results challenge the assumptions that girls are often considered more likely to be affected by malnutrition in the nutritional community. Recent studies focused on the relationship between waste and lightning have also highlighted similar results that show that children are more likely to be wasted and stunned than girls and have identified this as an unexpected finding. We find that even when sexual differences are reported, they are not always recognized or explored. A little more than a quarter of studies (28%) did not provide any discussion of the reported differences and 14% cited similar findings but did not consider causes. When explanations were provided on sexual differences in the prevalence of malnutrition, almost half (49%) of the studies examined offered explanations related to social reasons or based on speculation or preconceived assumption rather than evidence. The search criteria used (which filtered articles to those who use terms related to sex or gender in abstract) could have introduced some prejudices here with a possible overestimation of studies that report and explore the issue of sexual differences. When stratified by age, meta-analysis also shows that children are at greater risk in all age groups, although again, our analysis can mask some of the complexities of age as a detailed analysis of different age groups was not possible. While the results for age show that boys are more likely to be stunned than girls, RWs are lower in the older age group compared to the younger group. Limited data in the 24 to 59 months category, especially for waste and low weight, however, average results should be interpreted with caution. These interim results may indicate that any risk specific to sex differs in different ages: a more in-depth study is justified. Two studies that explore simultaneous waste and stunt found that it was a condition that affects children under 30 months more than older children, and found that sexual intercourse in malnourished children changes with age, with greater susceptibility for children up to 30 months who later disappeared. In addition to other studies, they suggest that sexual hormones, specifically testosterone, luteinizing hormones and follicle-stimulating hormones could play a role in this. The selection effects can also contribute to this, so if children are more likely to die than girls, the group of children who still remain would represent healthy survivors. Adair and Guilkey studied children in the Philippines and found that men were more likely to be stunned in the first year of life (using the reference of the NCHS), but women were more likely than men to be stunned in the second year. They suggest that differences in parental care behaviors may take part in this finding, but were not measured in the study. Bork and Diallo also found evidence of interaction between age and sex in which the deficit of boys compared to that of girls increased between the first and second years of life, regardless of the indicator used. However, differences in height status were sensitive to the chosen growth reference; they were higher when evaluated using WHO growth standards in 2006 than when the CNS growth reference was used. Gender differences in malnutrition can vary not only by geographical area but also over time. When diseases that cause malnutrition are more severe among girls, such as measles, cough and tuberculosis, they disappear due to vaccination, lower transmission and better feeding, the disadvantage of children could increase. On the contrary, if efficient nutrition programmes were implemented, the disadvantage of children could be reduced over the years. The interpretation of these conclusions on the consequences for practice and politics is limited at this stage, but it does deserve consideration and some degree of change. At the very least, systematic collection and reporting of age- and sex-disaggregated data should be included in the design of programmes and assessments in all settings. Where differences are observed, particularly in programme admissions, they should be interpreted taking into account gender differences in the population ' s burden, in order to draw conclusions on whether programmes are demonstrating equal access for boys and girls, and then the possible causes of such differences should be considered or investigated. At present, the vulnerability of children to malnutrition is seldom a consideration in the design of nutritional programming, or in the formulation of policies. In addition, some high-level international nutrition policies explicitly focus on the vulnerability of women and girls (e.g., the Nutrition Movement for Development Road Map 2016–2020) Khara et al. ). Furthermore, the recent guidance of the Inter-Agency Standing Committee on Gender in Humanitarian Activities recognizes the inequality in food intake that can be faced by women and girls in crisis, but does not refer to higher levels of malnutrition among children. The lack of reflection on gender or misuse of the term to highlight only the health of women and girls is likely to involuntarily reinforce health inequalities. At the summit () and beyond Growth Nutrition 2020, it will focus on inequalities in malnutrition and how they affect different groups in different places. The emerging results of this review are important to ensure that these sexual differences are examined through a goal of equity. Strength and Limitations One of the strengths of this study lies in the systematic approach that was chosen and its main objective of examining gender differences in malnutrition in a wide geographical area. However, there are areas where prejudice has been introduced. First, only one of the authors performed a study test to include them in this study. While we use systems to ensure that contentious articles are discussed between two or more authors, we recognize that not using double detection is a limitation. Second, the search strategy for explicit sex or gender mention in the summary could have been biased to studies reporting on sex and gender in the summary, or to studies that found a significant difference, and therefore sexual differences could be unreported or over-reported in this study. Also, the search may have limited the analysis as there are potentially lost studies that include sex as an analysis variable, but not focusing on mentioning sex in the abstracts of the study. There may also be some degree of bias in the publication by which sexual differences are simply not considered or communicated. The search criteria also covered a large number of studies with different objectives that mean a limited degree of homogeneity. Few studies directly assessed the true relationship between sex and malnutrition. Therefore, this analysis is potentially biased by healthy survivors—those children who have survived to be included in studies. We do not believe, however, that our results would be significantly different considering the evidence presented on male vulnerability. We also recognize the possibility of overlapping data used by sources such as Demographic and Health Surveys (DHS). By comparing the dates and places of the studies included, we have been unable to establish any overlap. Therefore, it is likely that the unidentified overlap will be minimal in our examination and may not affect the general conclusions. When there are multiple studies available in the same country, we have established that they are from different regions and times, therefore their inclusion as independent studies is justified. We hope that our review will encourage future work to explore not only differences between countries but also intranational/regional differences, as this will help to understand the biological and social reasons of any difference in male/female risks. While this analysis included some secondary data from DHS, the topic concerned could benefit from a systematic analysis of DHS, multiple indicator surveys and nutrition survey data. Although the result of RWs of sexual differences is not believed to be different, further analysis could help improve understanding of some of the complexities of age, context, double burdens of malnutrition and sexual differences and the consequences for programmers. This could also help explain some of the heterogeneities between studies we identified but could not explain with our analysis. The rigor of the findings of the analysis is limited in relation to age, as the grouping and degree of available data potentially mask some of the differences in the different stages of the life cycle, in a similar way, the geographical differences could be biased towards the studies included through the search. The absence of data on other anthropometric measures, such as the Mid-term Arms Circumference (MUAC), is also a potential limitation. In considering the implications of the differences highlighted here, in addition to biological and social explanations, it is necessary to consider how we measure and define malnutrition and whether sexual differences are an artifact of the use indices. WHO growth standards describe physiological growth in optimal environmental conditions and are separated by sex. These well-nourished healthy population reference data resolve gender differences to zero by expressing data as calculated z-scores using the appropriate male and female subset of the reference population. However, it is not clear whether we expect the gender differences in malnutrition expressed in this way to be zero, when the weight and height distribution in both sexes has been removed from the healthy reference range. It is also unclear whether the loss of the same amount of body weight in a child would have the same physiological effect. If children are facing worse than girls when exposed to food shortages or illnesses and infections, this may highlight a greater vulnerability to what has already been explained in the rules. In comparison, MUAC cuts are not adjusted and are not differentiated by sex or age (between 6 months and 5 years). This lack of adjustment can result in a preferential inclusion of girls in programmes compared to what would be achieved if specific sex standards were used, as girls tend to have less MUAC than boys. Although it has been shown to be a good predictor of mortality, sexual differences in the use of MUAC to define malnutrition have not been widely studied. Finally, the number of studies identified in the general search that he described for metaanalysis was low. This was mainly due to the lack of disaggregated data. A recent Lancet series on gender equality, standards and health highlighted the need for accurate disaggregated data. Consequences for future research This study is a step towards a better understanding of gender differences in malnutrition and emphasizes the need to consider possible implications for policy and practice. Future research should be aimed at getting rid of complexities related to age, biological and social risks (including gender norms) and context. In particular, we note that the current documents are conjectures on the reasons for the observed differences. Any hypothesis should be more directly tested in future studies to improve our understanding of sexual differences in the context of malnutrition and subregional variations in order to determine the impact of such differences on programme staff and policymakers. Future research will focus on a more detailed analysis of factors affecting the results of children, such as epidemiological, demographic and social differences, exploring the consequences of sex, age and behavioural differences in nutritional results and mortality. The impact of using different anthropometric indices and measurements should also be studied to better understand how the different methods detect the most vulnerable children and explore how substantial sexual differences are. Conclusion This review demonstrates that malnutrition defined by anthropometric case definitions is usually greater among boys than among girls. While further research is needed to understand the implications of policies and the programming of these differences, lessons can already be drawn from this research. We call on nutrition actors to improve data collection in programmes, surveys and research through comprehensive gender and age breakdown and analysis, in order to identify the most vulnerable children in specific contexts, and to allow comparison of programme data with population-level burdens. It is important to understand that the message of this study is not that children are prioritized on girls, but rather seek to support all children at risk, through a better understanding of sexual differences in malnutrition. Ultimately, we believe that all children under the age of 5 and their caregivers should be considered a high-priority group for specific nutrition interventions, and resources and interventions should be targeted as needed. Acknowledgements We would like to acknowledge and thank Zoe Thomas at the London School of Hygiene and Tropical Medicine Library for reviewing the search terms used in this study. ReferencesFootnotes Handling editor Seye AbimbolaTwitter @charlesopondo, @GlobalHealthNutContributors The review was designed and performed by ST with MK and RS supervision. Metaanalysis was led by ST supported by CO. ST led the manuscript writing for publication with contributions from all authors. Financing This document is possible thanks to the funding of Irish Aid (number of HQPU/2020/ENN) and the generous support of the American people through the United States Agency for International Development (USAID). Competing interests None declared. Consent of the patient for publication It is not necessary. Provenance and peer review It has not been commissioned; it has been externally examined among counterparts. Data availability statement The data used were published studies available in a public open access repository. Datasets generated for the current study are available by the corresponding author at reasonable request. Supplementary material This content has been supplied by the author or the authors. It has not been investigated by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. The views or recommendations examined are only those of the author or the authors and are not supported by BMJ. BMJ rejects any liability and liability arising from any unit that has been deposited in the content. When the content includes any translated material, BMJ does not guarantee the accuracy and reliability of translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug doses), and is not responsible for any errors and/or omissions resulting from translation and adaptation or otherwise. Request for permissions If you wish to reuse any or all of this article, please use the link below that will take you to the RightsLink Service of the Copyright Settlement Center. You will be able to get a quick price and instant permission to reuse the content in many different ways. Copyright Information: Read the full text or download the PDF: Sign in using your username and passwordOnline: ISSN 2059-7908 Copyright © 2021 BMJ Publishing Group Ltd. All rights reserved. 4.00ICP sponsors15042040 forwarded-3