Skip to main content
Advertisement
  • Loading metrics

Predictors of change in early child development among children with stunting: Secondary analysis of a randomized trial in Uganda

  • Joseph Mbabazi ,

    Roles Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Project administration, Software, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing

    mjosef2000@gmail.com

    Affiliations Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark, Department of Paediatrics and Child Health, Makerere University, Kampala, Uganda

  • Hannah Pesu,

    Roles Conceptualization, Data curation, Investigation, Methodology, Project administration, Software, Supervision, Writing – review & editing

    Affiliation Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark

  • Rolland Mutumba,

    Roles Conceptualization, Data curation, Investigation, Methodology, Project administration, Supervision, Writing – review & editing

    Affiliations Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark, Department of Paediatrics and Child Health, Makerere University, Kampala, Uganda

  • Gareth McCray,

    Roles Formal analysis, Methodology, Software, Writing – review & editing

    Affiliation School of Medicine, Keele University, Keele, Staffordshire, United Kingdom

  • Christian Ritz,

    Roles Data curation, Formal analysis, Methodology, Software, Validation, Writing – review & editing

    Affiliation The National Institute of Public Health, University of Southern Denmark, Odense, Denmark

  • Suzanne Filteau,

    Roles Formal analysis, Visualization, Writing – review & editing

    Affiliation Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom

  • André Briend,

    Roles Formal analysis, Visualization, Writing – review & editing

    Affiliations Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark, Faculty of Medicine and Health Technology, Tampere Center for Child, Adolescent and Maternal Health Research, Tampere University and Tampere University Hospital, Tampere, Finland

  • Ezekiel Mupere,

    Roles Conceptualization, Formal analysis, Investigation, Methodology, Project administration, Supervision, Visualization, Writing – review & editing

    Affiliation Department of Paediatrics and Child Health, Makerere University, Kampala, Uganda

  • Benedikte Grenov,

    Roles Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Project administration, Resources, Supervision, Visualization, Writing – review & editing

    Affiliation Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark

  • Henrik Friis,

    Roles Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Resources, Software, Validation, Visualization, Writing – review & editing

    Affiliation Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark

  • Mette F. Olsen

    Roles Data curation, Formal analysis, Methodology, Validation, Visualization, Writing – review & editing

    Affiliations Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark, Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark

Abstract

Millions of children under 5 years in low- and middle-income countries fail to attain their development potential with accruing short- and long-term consequences. Low length/height for age (stunting) is known to be a key factor, but there is little data on how child characteristics are linked with developmental changes among children with stunting. We assessed the socioeconomic, household, anthropometric, and clinical predictors of change in early child development (ECD) among 1–5-year-old children with stunting. This was a prospective cohort study nested in a randomized trial testing effects of lipid-based nutrient supplementation among children with stunting in Uganda. Development was assessed using the Malawi Development Assessment Tool (MDAT). Multiple linear regression analysis was used to assess for predictors of change. We included 750 children with mean ±SD age of 30.2 ±11.7 months 45% of whom were female. After 12 weeks, total MDAT z-score increased by 0.40 (95%CI: 0.32; 0.48). Moderate vs severe stunting, higher fat-free mass, negative malaria test and no inflammation (serum α-1-acid glycoprotein <1 g/l) at baseline predicted greater increase in ECD scores. Older age and fat mass gain predicted a lesser increase in ECD. Our findings reinforce the link between stunting and development with more severely stunted children having a lesser increase in ECD scores over time. Younger age, freedom from malaria and inflammation, and higher fat-free mass at baseline, as well as less gain of fat mass during follow-up predicted a higher increase in developmental scores in this study. Thus, supporting fat-free mass accretion, focusing on younger children, and infection prevention may improve development among children with stunting.

Introduction

Over 250 million children under 5 years of age in low- and middle-income country settings (LMICs) are unable to reach their full development potential in physical, cognitive, and socioemotional domains [1]. This has both short- and long-term implications including on their educational attainment and executive functioning in adult life which, in turn, affects productivity and consequently propagates the poverty cycle [2]. Notable risk factors include, poor home stimulation, child stunting, and micronutrient deficiencies especially in iron and iodine [3]. With the prevailing conditions including likely global economic recessions, climate change, and the post-corona pandemic context, the number of affected children is likely to increase [4]. Various stakeholders have thus called for interventions integrating health, nutrition, and stimulation to promote early child development (ECD). However, there is limited evidence on feasible approaches to alleviate delayed child development.

Child stunting, defined by a height-for-age z-score (HAZ) below -2 [5], is a form of chronic undernutrition, and has been associated with poor ECD [6]. Stunting is the most prevalent form of undernutrition with over 149 million children under 5 years affected globally [7] and is a key target for reduction (at least by 40%) by 2025 [8]. Since children tend to acquire skills by interacting with people and their surroundings [9], malnourished children including those with stunting and/or micronutrient deficiencies are more likely to be disadvantaged as they tend to be passive with limited exploration of their environment [10,11] compared to children without stunting. Furthermore, nutrient deficiencies are likely to impair brain development and cognition [12]. Factors associated with development among children with stunting are not well documented, although among well-nourished children, socioeconomic status, father’s involvement in child rearing, head circumference, and home stimulation have been associated with improved ECD [13,14].

We previously conducted a randomized community-based 2x2 factorial trial where we found no effect of milk protein (MP) vs soy, or whey permeate (WP) vs maltodextrin in large-quantity lipid nutrient supplement (LNS), or of LNS vs no LNS on ECD among 1–5-year-old stunted Ugandan children [15]. Stunting has been associated with poor cognitive development although the causal relationship is unknown [16]. We sought to assess the factors associated with change in ECD over the 12-weeks’ follow-up period. Our findings may inform ECD programs and other relevant key stakeholders about methods to alleviate developmental delay among stunted children and its likely consequences.

Materials and methods

Study design

We conducted a prospective cohort study using data collected in stunted children enrolled as part of the MAGNUS trial (ISRCTN13093195) from 7th February to 17th September 2020. Village-level screening was temporarily halted between 26th March to 14th June due to global corona virus pandemic. The study protocol [17] and main trial outcome [18] have already been described elsewhere. The current study considered all 750 children with stunting who were enrolled and followed-up regardless of study arm.

Study participants

The study was conducted in Jinja district in East Central Uganda at two public health facilities of Walukuba division (Jinja city) and Buwenge Town Council (Jinja rural). Study participants were recruited from the surrounding villages with the help of village health teams. Children with HAZ <-2 and weight-for-height z-score (WHZ) ≥-3, were referred to the nearby study clinic for eligibility screening. Those with severe acute malnutrition (SAM) marked by WHZ <-3, mid-upper-arm circumference (MUAC) <115 mm, or bilateral pitting oedema were referred for appropriate treatment.

Children were enrolled at the study clinics if i) they lived within the catchment area, ii) had caregivers willing to return for follow-up visits, and iii) agreed to phone-follow-up plus home visit. Children were excluded if they had i) SAM, ii) medical complications requiring hospitalization, iii) peanut or milk allergy history, iv) obvious disability impeding eating or measurement of anthropometric outcomes, v) were participating in another study, vi) the family planned to relocate in the subsequent six months or, vii) the family had another participating child from the same household.

Study visits

Participants returned fortnightly to refill supplement (intervention group) or laundry soap (reference group) until the 12th week, as described in detail elsewhere [17,18]. At baseline, data was collected on demography, dietary intake including breastfeeding, food insecurity, household income, and anthropometry. Blood samples were collected for assessment of haemoglobin, malaria infection, and acute-phase proteins. Child development assessment and scoring of the child’s participation level during tests were done at baseline and endline. The child was assessed on how happy, engaged, cooperative, and anxious they were during majority of the tests based on an adapted version of the Behaviour Observation Inventory from the Bayley Scales of Infant and Toddler Development [19] as previously used to support MDAT assessment [20,21]. Additionally, caregivers were asked about the child’s developmental stimulation at home using an African-validated family care indicators (FCI) questionnaire [22] at baseline. These were asked about the home stimulation level in four subscales of (i) availability of any child reading materials, (ii) sources of play materials, (iii) variety of play materials, and (iv) engagement with any adult member (15+ years old) in various interactive activities at home. The interactive activities included reading books, telling stories, singing songs, taking the child out, playing with the child, and counting or drawing for the child. The FCI scale has been validated and adapted for use including in such settings [22,23].

Outcomes

Change in child development was determined as the difference between the endline and baseline developmental score. Development was measured using the Malawi Development Assessment Tool (MDAT) version 6 [24] translated into Lusoga and Luganda. This tool was developed in an African setting and is adapted and validated for use in LMICs including Uganda. It focuses on four domains gross motor, fine motor, language, and social skills development with 39, 42, 40 and 36 milestones in each domain, respectively. The MDAT is primarily an observation-based tool with standardized items assessed by a trained research assistant referred to as a child development officer (CDO).

During assessments, most of the milestones are observed while some, mainly in the social domain, are assessed based on caregiver report. Normal age-specific reference values for each domain are used as a starting point while testing each child. The CDO first performed a forward test until the child failed six consecutive items thereby marking the rest of the items above as failed. If the child passed six consecutive items in the forward test, all items below were marked passed; otherwise, a backward test was performed until six consecutive items were passed. After every twenty assessments, per CDO, a quality check was performed. Specifically, another CDO performed a concurrent assessment and results were compared. In case of any discrepancy, consensus was arrived at in consultations with the respective standard operating procedure and views from other CDOs. The child and caregiver’s participation during the MDAT assessment was observed by the CDO.

Potential predictors of change in child development

Questionnaires were used at baseline to collect sociodemographic and socioeconomic data. Breastfeeding status was assessed by asking the mother if the child was still breastfeeding. Dietary intake was based on 24-hour recall. Food security was calculated using the USAID household food insecurity access scale [25] while dietary diversity was calculated based on the WHO global nutrition monitoring framework operational guidance [26]. All caregivers received nutrition counselling using the national guidelines on infant and young child feeding [27]. Household wealth index was determined using a 3-stage principal components analysis as used in the demographic and health survey program [28,29].

Anthropometric measurements were done in triplicate and the median used. Participant’s weight, height/length, and head circumference at baseline were all measured as described elsewhere [18]. Body composition was measured in duplicate by bioelectrical impedance using Bodystat 500 machine at 50 kHz (Bodystat, Isle of Man, United Kingdom) as described in detail in the main trial paper [18] and in the methodology paper [30]. We used both the baseline, and change in body composition level over the follow-up period.

Venous blood was drawn from each child, transported to the field laboratory, processed, and temporarily stored at -20°C before being transported to Kampala for storage at -80°C. Processed samples were later transferred to Germany on dry ice for analysis of the acute phase proteins using sandwich enzyme-linked immunosorbent assay (Vitmin Lab, Willstaett, Germany). Before processing, whole blood was used to diagnose malaria (rapid diagnostic test RDT, SD bioline malaria Ag Pf, Abbott, USA) and to measure haemoglobin concentration (Hb201+, HemoCue, Sweden).

Data management and statistical analyses

Data were collected using paper case report forms (CRF) and double entered in EpiData (Epidata Association, Odense, Denmark) with inbuilt range checks before periodic submission to a secure server using REDCap (Open-Source Vanderbilt University). Statistical analysis was done using Stata SE14 (StataCorp LP, College Station, TX, USA). Descriptive statistics are reported as mean ±SD, median [interquartile range] and frequency, %(n).

We generated MDAT developmental age-adjusted z-scores via a procedure similar to that used in the recent GSED tool [31] (code available on request). The DAZ values were normed on the study sample rather than on an external sample as the study sample was sufficiently large to allow accurate parameter estimation. The advantage of norming within study is that the Scores and the DAZ values do not rely on an external standard that might not generalize well to the data in this study. To calculate DAZ values, first, an item response theory (IRT) analysis was conducted using unidimensional 2-parameter-logistic (2PL) [32] models in the R package ‘mirt’ [33] to create both overall (total) and domain specific scores for each child at each timepoint. Thereafter, a GAMLSS was utilized, using the R package ‘gamlss’ [34] to generate age contingent z-score measures of ability based upon the development scores from IRT model. See S1 Fig for plots of an example of GAMLSS model fit.

Multiple linear regression analysis was used to assess predictors of change in gross motor, fine motor, language development, social skills and the total MDAT z-scores. Potential predictors included sociodemographic status (age, sex, urban residence, household size, and LNS intervention), and socioeconomic factors (multiple income earners, maternal schooling, female-headed households [FHH], food expenditure, food security, dietary diversity, breastfeeding and wealth index).

Family care indicators, as proxies for household stimulation, were also assessed for their prediction. These included having any children’s book at home, >2 sources of play materials, >3 varieties of play materials, interaction with older family members (15+ years old) in > 3 interactive activities at home, and a combination of all the four as described elsewhere including choice of cutoffs [15,35].

We also assessed anthropometric factors for association with change in development including HAZ, WHZ, and head circumference (mm). Additionally, we assessed prediction by body composition data: fat mass (FM), and fat-free mass (FFM) in kilograms, and fat mass index (FMI) and fat-free mass index (FFMI) in kg/m2 which are independent of height. Changes in these variables over the follow-up period were referred to as ΔFM, ΔFFM, ΔFMI, and ΔFFMI.

Clinical factors including malaria (positive RDT), anaemia (Hb <110 g/l), inflammatory markers C-reactive protein (CRP, ≥10 mg/l) and α-1-acid glycoprotein (AGP, ≥1 g/l) were assessed for association with change in development. In all our analysis, we adjusted for age, sex, and intervention with LNS irrespective of dairy. A significance level of 0.05 was applied.

Ethical statement

The study was approved by the School of Medicine Research and Ethics Committee of Makerere University, Kampala (#REC REF 2019–013) and the Uganda National Council of Science and Technology (SS 4927). A consultative approval was obtained from the Danish National Committee on Biomedical Research Ethics (1906848). The study was conducted in accordance with the principles of the Helsinki Declaration [36] and followed local guidelines for human research. All study staff undertook a course in Good Clinical Practice (GCP) and Human Subject Protection (HSP). Oral and written information was provided in Lusoga, Luganda or English. Before caregivers gave written informed consent, their understanding of the information was checked by a different staff member, using a questionnaire.

Results

A total of 750 children with stunting aged 12–59 months were enrolled in this study. After 12 weeks, 736 children (98%) completed the follow-up study as reported in detail elsewhere [15,18].

The mean ±SD age was 32.0 ±11.74 months, 45% were female and 55% resided in rural areas (Table 1). Only a quarter of the households spent <50% of their income on food and 4.4% had secure food access. A minority (12.7%) of children were currently breastfed (Table 1). Household average combined wealth index score was 0.30 ±1.11. A third of families had at least one children’s book and 31% had more than three varieties of play materials at home, but only 9.5% had a stimulative home environment. The average HAZ at inclusion was -3.02 ±0.74, with a weight of 10.59 ±1.98 kg of which 1.80 ±0.87 kg was fat mass. Around 40% tested positive for malaria while over two-thirds had anaemia.

thumbnail
Table 1. Baseline characteristics of 750 children with stunting1.

https://doi.org/10.1371/journal.pgph.0003456.t001

There was significant (p<0.001) change across all MDAT domains at the end of 12-week follow-up. The mean changes in developmental z-scores were: gross motor: 0.37 (95%CI: 0.28; 0.45); fine motor: 0.26 (95%CI: 0.17; 0.35); language: 0.31 (95%CI: 0.22; 0.39); social skills: 0.28 (95%CI: 0.19; 0.36); and total score: 0.40 (95%CI: 0.32; 0.48) (Table 2).

thumbnail
Table 2. Change in MDAT z-scores among stunted children during the 12 weeks follow up1.

https://doi.org/10.1371/journal.pgph.0003456.t002

After age, sex, and adjustment for intervention with LNS regardless of milk ingredients, older children had 0.08 (95%CI: 0.01; 0.15) lesser increase in total MDAT z-score (Table 3A). This was driven by 0.07 (95%CI: 0.002; 0.14) and 0.08 (95%CI: 0.01; 0.15) lower change in gross motor and language z-scores respectively. Conversely, for each 1 kg fat gain, there was a corresponding 0.23 (95%CI: -0.08; -0.39) lesser increase in the total MDAT z-score and this was driven by lesser increase in all the four MDAT domains (Table 3B).

thumbnail
Table 3. a. Sociodemographic, socioeconomic and household predictors of change in child development among 736 children with stunting1.

b. Anthropometric predictors of change in child development among 736 children with stunting. c. Clinical predictors of change in child development among children with stunting1.

https://doi.org/10.1371/journal.pgph.0003456.t003

For every unit higher HAZ at baseline, there was a corresponding 0.16 (95%CI: 0.07; 0.25) higher increase in total MDAT z-score (Table 3B). This was as a result of 0.15 (95%CI: 0.05; 0.24), 0.12 (95%CI: 0.03; 0.21), and 0.16 (95%CI: 0.07; 0.25), greater difference in gross motor, fine motor, and language z-scores, respectively. Baseline higher fat-free mass composition was associated with 0.17 (95%CI: 0.05; 0.29) greater increase in total MDAT z-score driven by higher changes in gross motor and language z-scores (Table 3B). Children without malaria or inflammation at baseline had 0.24 (95%CI: 0.11; 0.37) and 0.22 (95%CI: 0.09; 0.36) greater increase in total MDAT z-scores, respectively (Table 3C). This was driven by greater changes in gross, fine motor, and language z-scores.

Currently breastfed children at baseline had 0.23 (95%CI: 0.002; 0.45) lesser increase in fine motor z-scores, but no differences from non-breastfed in other domains (Table 3A). Children from households with a stimulative home environment were associated with 0.52 (95%CI: 0.14; 0.91) and 0.39 (95%CI: 0.02; 0.77) higher increase in gross motor and social skills z-scores respectively (Table 3A). This was partly driven by possession of greater than three varieties of play material and having any children’s books which were associated with 0.15 (95%CI: 0.001; 0.30) higher increase in gross motor and 0.16 (95%CI: 0.02; 0.30) higher increase in language z-scores. Wealth quintile was not associated with changes in development. Each 1 cm higher head circumference at baseline was associated with 0.06 (95%CI: 0.01; 0.11) higher increase in fine motor z-score, but no notable increase in z-scores across other developmental domains (Table 3B).

At endline, children were overall more engaged, cooperative and not anxious than at baseline (S1 Table).

Discussion

As in children without stunting, our findings derived from the summative total score reveal that improved development is attainable with higher HAZ scores, at early ages, with fat-free but not fat mass accretion, and being free of infections indicated by inflammation and malaria rapid test. Whereas head circumference was associated with higher increase in fine motor, the reverse was true for prolonged breastfeeding. Coming from a stimulative home was associated with greater increases especially in gross motor and social skill scores.

Our findings on HAZ and head circumference association concur with results from the MAL-ED study [14] from various LMICs. In their study, head circumference was a stronger predictor of ECD at 24 months especially on cognitive development with over ~0.7 cognitive score increases at 24 months per unit z-score increase in head circumference. Conversely, each unit increase in length-for-age z-score resulted in ~0.2 increase in cognitive score [14]. In our study, our point estimates are lower than what was registered in the MAL-ED study that is 0.06 vs 0.7 and 0.12 vs 0.2 for head circumference and HAZ change in fine motor score respectively. Of note, we had much older children (1–5 years vs 0–24 months), who were already stunted followed up for only 3 vs 24 months. The associations between stunting level and head circumference with ECD has already been described elsewhere [6,14], including in our analysis of baseline developmental scores among these children [35].

A study among pre- and full-term children followed up from infancy through preschool age revealed that higher 4-month corrected age to 4-year FFM gain was associated with higher full scale intelligence quotient (IQ) [37]. Among the full-term group, higher 4-month to 4-year fat mass gains were associated with lower full-scale IQ. Although their study was from a high-income setting with a longer follow-up period (48 months), our findings are similar with respect to FFM and fat mass gain. This is also in line with an Ethiopian study where FFM at birth, but not FM, was associated positively with global developmental score (2.48, 95%CI: 0.17; 4.79) at 2 years, mainly attributable to language skills development [38]. There has also been evidence suggesting that lean tissue growth optimizes competing cognitive and metabolic consequences [39]. We are likely to have a similar trend even among stunted children augmented by the fact that, compared to those that were supplemented, unsupplemented children in this study gained mainly fat mass at the expense of FFM [18].

Low acute phase proteins and negative malaria RDT were associated with greater increase in developmental scores, similar to findings from other cohort studies [40]. Healthy children without malaria or inflammation may be more active with lesser toll on their immunity and nutrients hence greater increase in ECD scores. This is also aligned with our baseline findings where those children with elevated serum AGP and positive malaria RDT had lower ECD scores [35].

The early pre- and postnatal period is characterized by rapid maturation of metabolic, endocrine, neural, and immune pathways, which all have a strong bearing on child growth and development [41]. These pathways develop in tandem with a complex assembly program reliant on both internal and external factors which are susceptible to such adversities like infections and suboptimal feeding [41].

Similar to our baseline findings [35], prolonged breastfeeding was associated with lower change but only in fine motor. Contrary to the expected and well documented evidence that breastfeeding is associated with better development [42], it has been noted in recent literature that this relationship is prone to confounding. Further adjustments for socioeconomic status and maternal cognition tend to reduce the association, especially at older ages [43]. Reverse-causality may also contribute because mothers may have preferred to support children with poor anthropometry and/or other complications by prolonging breastfeeding. Indeed, stunted children in this study that were still breastfed had worse anthropometric indices, more cases of anaemia and cobalamin deficiency [35]. Prolonged breastfeeding may be a counter measure for various disruptions which could be partly why we saw lower change in their fine motor scores.

A stimulative home environment marked especially by availability of children’s books, and >3 varieties of play materials was associated with greater increase in gross motor and social skills in agreement with findings from a path analysis of the iLiNs trials [44]. Having books and more varied play materials is likely to promote caregiver activities with children to a greater extent hence more stimulation promoting development. This and other established associations, moreover among impoverished stunted children in Uganda could guide implementation of the ECD policy which is now a focus of full adoption by the government.

Key strengths of our study include a large sample of children with stunting, assessment of a variety of probable predictors, and use of a contextually appropriate tool for assessment of child development (MDAT). Key limitations include inability to establish causal relationships given the observational nature of the reported associations. In addition, we were unable to measure how much change in developmental scores was attributable to the ‘learning effect’ of the MDAT as acknowledged elsewhere [21]. Our finding that children were more cooperative, engaged with enthusiasm, unfearful and not anxious during endline, compared to baseline MDAT assessments suggests that perhaps there was a notable attributable change due to the learning effect of the tool.

Conclusions and recommendations

Findings from our study reinforce existing ECD management program core objectives such as stunting alleviation to foster good ECD. However, to be effective, these should be timely, focusing on younger children, and should be supported by nutrition interventions supporting fat-free, rather than fat mass accretion. Continued efforts to reduce malaria and inflammation and to promote stimulating home environments may also promote higher ECD changes even among stunted children in LMICs like Uganda.

Supporting information

S1 Table. Mother and Child cooperativeness during MDAT assessments among 736 children with stunting.

https://doi.org/10.1371/journal.pgph.0003456.s001

(XLSX)

S1 Fig. Plots of the scaled and Z-scores (DAZ) for total MDAT score.

https://doi.org/10.1371/journal.pgph.0003456.s002

(TIFF)

References

  1. 1. Black MM, Walker SP, Fernald LC, Andersen CT, DiGirolamo AM, Lu C, et al. Early childhood development coming of age: science through the life course. The Lancet. 2017;389(10064):77–90. pmid:27717614
  2. 2. Engle PL, Black MM, Behrman JR, De Mello MC, Gertler PJ, Kapiriri L, et al. Strategies to avoid the loss of developmental potential in more than 200 million children in the developing world. The lancet. 2007;369(9557):229–42. pmid:17240290
  3. 3. Walker SP, Wachs TD, Grantham-McGregor S, Black MM, Nelson CA, Huffman SL, et al. Inequality in early childhood: risk and protective factors for early child development. The Lancet. 2011;378(9799):1325–38. pmid:21944375
  4. 4. Sheffield PE, Landrigan PJ. Global climate change and children’s health: threats and strategies for prevention. Environmental health perspectives. 2011;119(3):291–8. pmid:20947468
  5. 5. WHO. WHO Child Growth Standards based on length/height, weight and age. Acta paediatrica. 2006;95:76–85. pmid:16817681
  6. 6. Perkins JM, Kim R, Krishna A, McGovern M, Aguayo VM, Subramanian S. Understanding the association between stunting and child development in low-and middle-income countries: Next steps for research and intervention. Social Science & Medicine. 2017;193:101–9.
  7. 7. UNICEF W, World Bank. Joint child malnutrition estimates inter-agency group regular updates. The global health observatory: WHO; 2021.
  8. 8. WHO. Global Targets 2025: To improve maternal, infant and young child nutrition. Geneva Switzerland: World Health Organization; 2012.
  9. 9. Biglan A, Flay BR, Embry DD, Sandler IN. The critical role of nurturing environments for promoting human well-being. American Psychologist. 2012;67(4):257. pmid:22583340
  10. 10. Gardner JMM, Grantham‐McGregor SM, Chang SM, Himes JH, Powell CA. Activity and behavioral development in stunted and nonstunted children and response to nutritional supplementation. Child development. 1995;66(6):1785–97. pmid:8556899
  11. 11. Lozoff B, Klein NK, Nelson EC, McClish DK, Manuel M, Chacon ME. Behavior of infants with iron‐deficiency anemia. Child development. 1998;69(1):24–36. pmid:9499554
  12. 12. Georgieff MK, Ramel SE, Cusick SE. Nutritional influences on brain development. Acta Paediatrica. 2018;107(8):1310–21. pmid:29468731
  13. 13. Hoff E, Laursen B. Socioeconomic status and parenting. Handbook of parenting: Routledge; 2019. p. 421–47.
  14. 14. Scharf RJ, Rogawski ET, Murray‐Kolb LE, Maphula A, Svensen E, Tofail F, et al. Early childhood growth and cognitive outcomes: Findings from the MAL‐ED study. Maternal & child nutrition. 2018;14(3):e12584. pmid:29392824
  15. 15. Mbabazi J, Pesu H, Mutumba R, McCray G, Michaelsen KF, Ritz C, et al. Effect of Milk Protein and Whey Permeate in Large-Quantity Lipid-Based Nutrient Supplement on Early Child Development among Children with Stunting: A Randomized 2× 2 Factorial Trial in Uganda. Nutrients. 2023;15(12):2659.
  16. 16. Leroy JL, Frongillo EA. Perspective: what does stunting really mean? A critical review of the evidence. Advances in Nutrition. 2019;10(2):196–204. pmid:30801614
  17. 17. Pesu H, Mutumba R, Mbabazi J, Olsen MF, Mølgaard C, Michaelsen KF, et al. The role of milk protein and whey permeate in lipid-based nutrient supplements on the growth and development of stunted children in Uganda: A randomized trial protocol (MAGNUS). Current developments in nutrition. 2021;5(5):nzab067. pmid:34027295
  18. 18. Mbabazi J, Pesu H, Mutumba R, Filteau S, Lewis JI, Wells JC, et al. Effect of milk protein and whey permeate in large quantity lipid-based nutrient supplement on linear growth and body composition among stunted children: A randomized 2× 2 factorial trial in Uganda. Plos Medicine. 2023;20(5):e1004227.
  19. 19. Bayley N. Bayley scales of infant and toddler development: PsychCorp, Pearson; 2006.
  20. 20. van den Heuvel M, Voskuijl W, Chidzalo K, Kerac M, Reijneveld SA, Bandsma R, et al. Developmental and behavioural problems in children with severe acute malnutrition in Malawi: A cross–sectional study. Journal of global health. 2017;7(2). pmid:29302321
  21. 21. Olsen MF, Iuel-Brockdorff A-S, Yaméogo CW, Cichon B, Fabiansen C, Filteau S, et al. Impact of food supplements on early child development in children with moderate acute malnutrition: A randomised 2 x 2 x 3 factorial trial in Burkina Faso. PLoS medicine. 2020;17(12):e1003442. pmid:33362221
  22. 22. Hamadani JD, Tofail F, Hilaly A, Huda SN, Engle P, Grantham-McGregor SM. Use of family care indicators and their relationship with child development in Bangladesh. Journal of health, population, and nutrition. 2010;28(1):23. pmid:20214083
  23. 23. Kariger P, Frongillo EA, Engle P, Britto PMR, Sywulka SM, Menon P. Indicators of family care for development for use in multicountry surveys. Journal of health, population, and nutrition. 2012;30(4):472. pmid:23304914
  24. 24. Gladstone M, Lancaster GA, Umar E, Nyirenda M, Kayira E, van den Broek NR, et al. The Malawi Developmental Assessment Tool (MDAT): the creation, validation, and reliability of a tool to assess child development in rural African settings. PLoS medicine. 2010;7(5):e1000273. pmid:20520849
  25. 25. Coates J, Swindale A, Bilinsky P. Household food insecurity access scale (HFIAS) for measurement of household food access: Indicator guide (v. 3). Washington, DC: food and nutrition technical assistance project, academy for educational Development. 2007:1–36.
  26. 26. Framework GNM. operational guidance for tracking progress in meeting targets for 2025. Geneva: World Health Organization. 2017.
  27. 27. MOH. Policy Guidelines on Infant and Young Child Feeding. January 2009. In: Ministry of Health U, editor. Kampala, Uganda2009.
  28. 28. Rutstein SO. Steps to constructing the new DHS Wealth Index. Rockville, MD: ICF International. 2015.
  29. 29. ICF UBoSUa. 2016 Uganda Demographic and Health Survey Key Findings. Uganda, and Rockville, Maryland, USA: UBOS and ICF; 2017.
  30. 30. Lewis JI, Friis H, Mupere E, Wells JC, Grenov B. Calibration of bioelectrical impedance analysis against deuterium dilution for body composition assessment in stunted Ugandan children. The Journal of Nutrition. 2023;153(2):426–34. pmid:36894235
  31. 31. Cavallera V, Lancaster G, Gladstone M, Black MM, McCray G, Nizar A, et al. Protocol for validation of the Global Scales for Early Development (GSED) for children under 3 years of age in seven countries. BMJ open. 2023;13(1):e062562. pmid:36693690
  32. 32. van der Linden WJ, Hambleton RK. Handbook of modern item response theory: Springer Science & Business Media; 2013.
  33. 33. Chalmers RP. mirt: A multidimensional item response theory package for the R environment. Journal of statistical Software. 2012;48:1–29.
  34. 34. Stasinopoulos M, Rigby B, Voudouris V, Akantziliotou C, Enea M, Kiose D. Package ‘gamlss’. Dist’2020Available online: http://wwwgamlssorg (accessed on 16 July 2021). 2023.
  35. 35. Joseph Mbabazi HP, Mutumba Rolland, Bromley Kieran, Mølgaard Christian, Michaelsen Kim F., Ritz Christian, et al. Correlates of early child development among children with stunting: a cross-sectional study in Uganda. Maternal & child nutrition 2023.
  36. 36. World Medical Association Declaration of Helsinki: ethical principles for medical research involving human subjects. J Am Coll Dent. 2014;81(3):14–8. pmid:25951678
  37. 37. Scheurer JM, Zhang L, Plummer EA, Hultgren SA, Demerath EW, Ramel SE. Body composition changes from infancy to 4 years and associations with early childhood cognition in preterm and full-term children. Neonatology. 2018;114(2):169–76. pmid:29898453
  38. 38. Abera M, Tesfaye M, Girma T, Hanlon C, Andersen GS, Wells JC, et al. Relation between body composition at birth and child development at 2 years of age: a prospective cohort study among Ethiopian children. European Journal of Clinical Nutrition. 2017;71(12):1411–7. pmid:28952606
  39. 39. Belfort MB, Gillman MW, Buka SL, Casey PH, McCormick MC. Preterm infant linear growth and adiposity gain: trade-offs for later weight status and intelligence quotient. The Journal of pediatrics. 2013;163(6):1564–9. e2. pmid:23910982
  40. 40. Olsen MF, Iuel‐Brockdorff AS, Yaméogo CW, Cichon B, Fabiansen C, Filteau S, et al. Early development in children with moderate acute malnutrition: A cross‐sectional study in Burkina Faso. Maternal & child nutrition. 2020;16(2):e12928. pmid:31823490
  41. 41. Robertson RC, Manges AR, Finlay BB, Prendergast AJ. The human microbiome and child growth–first 1000 days and beyond. Trends in microbiology. 2019;27(2):131–47. pmid:30529020
  42. 42. Horta BL, Loret de Mola C, Victora CG. Breastfeeding and intelligence: a systematic review and meta‐analysis. Acta paediatrica. 2015;104:14–9. pmid:26211556
  43. 43. Pereyra-Elías R, Quigley MA, Carson C. To what extent does confounding explain the association between breastfeeding duration and cognitive development up to age 14? Findings from the UK Millennium Cohort Study. PloS one. 2022;17(5):e0267326. pmid:35613097
  44. 44. Prado EL, Abbeddou S, Adu‐Afarwuah S, Arimond M, Ashorn P, Ashorn U, et al. Predictors and pathways of language and motor development in four prospective cohorts of young children in Ghana, Malawi, and Burkina Faso. Journal of Child Psychology and Psychiatry. 2017;58(11):1264–75. pmid:28543426