Sociocultural environmental factors and childhood stunting: qualitative studies - a protocol for the Shared Values theme of the UKRI GCRF Action Against Stunting Hub.

INTRODUCTION: Stunting is a significant and growing global problem that is resisting scientific attempts to understand it in terms of direct nutrition-related determinants. In recent years, research included more complex, indirect and multifactorial determinants and expanded to include multisectoral and lifestyle-related approaches. The United Kingdom Research Initiative Global Challenges Research Fund's (UKRI GCRF) Action Against Stunting Hub starts on the premise that dominant factors of stunting may vary between contexts and life phases of the child. Thus, the construction of a typology of clustered factors will be more useful to design effective programmes to alleviate it.The Shared Values theme seeks to build a bottom-up holistic picture of interlinked cultural contextual factors that might contribute to child stunting locally, by first eliciting shared values of the groups closest to the problem and then enquiring about details of their relevant daily activities and practices, to reveal links between the two. We define shared values as what groups consider 'valuable, worthwhile and meaningful' to them. METHODS AND ANALYSIS: We will recruit 12-25 local stakeholder groups in each site (in India, Indonesia and Senegal) involved in children's food and early learning environments, such as mothers, fathers, grandmothers, teachers, market vendors and health workers. The WeValue InSitu process will be used to assist them to collectively elicit, negotiate and self-articulate their own shared values through exploration of shared tacit knowledge. Focus group discussions held immediately subsequently will ask about daily activities relevant to the children's environment. These contain many examples of cultural contextual factors potentially influencing stunting locally, and intrinsically linked to shared values articulated in the previous session.

Anthropometric, biochemical, dietary, morbidity and well-being assessments in women and children in Indonesia, India and Senegal: a UKRI GCRF Action Against Stunting Hub protocol paper.

INTRODUCTION: Child stunting has a complex aetiology, especially in the first 1000 days of life. Nutrition interventions alone have not produced expected impacts in reducing/preventing child stunting, indicating the importance of understanding the complex interplay between environmental, physiological and psychological factors influencing child nutritional status. This study will investigate maternal and child nutrition, health and well-being status and associated factors through the assessment of: (1) anthropometry, (2) biomarkers of nutrition and health status, (3) dietary intakes, (4) fetal growth and development, (5) infant morbidity, (6) infant and young child feeding (IYCF) and (7) perinatal maternal stress, depression and social support. METHODS: This study will be conducted in a prospective pregnancy cohort in India, Indonesia and Senegal. Pregnant women will be recruited in the second (Indonesia, Senegal) and third (India) trimester of pregnancy, and the mother and infant dyads followed until the infant is 24 months of age. During pregnancy, anthropometric measures will be taken, venous blood samples will be collected for biochemical assessment of nutrition and health status, dietary intakes will be assessed using a 4-pass-24-hour dietary recall method (MP24HR), fetal ultrasound for assessment of fetal growth. After birth, anthropometry measurements will be taken, venous blood samples will be collected, MP24HR will be conducted, infant morbidity and IYCF practices will be assessed and a sample of breastmilk will be collected for nutrient composition analyses. Perinatal maternal stress, depression, social support and hair cortisol levels (stress) will be measured. The results from this study will be integrated in an interdisciplinary analysis to examine factors influencing infant growth and inform global efforts in reducing child stunting. ETHICS AND DISSEMINATION: Ethical approval was granted by the Ethics Committee of the London School of Hygiene and Tropical Medicine (17915/RR/17513); National Institute of Nutrition (ICMR)-Ministry of Health and Family Welfare, Government of India (CR/04/I/2021); Health Research Ethics Committee, University of Indonesia and Cipto Mangunkusumo Hospital (KET-887/UN2.F1/ETIK/PPM.00.02/2019); and the Comité National d'Ethique pour la Recherche en Santé, Senegal (Protocole SEN19/78); the Royal Veterinary College (URN SR2020-0197) and the International Livestock Research Institute Institutional Research Ethics Committee (ILRI-IREC2020-33). Results will be published in peer-reviewed journals and disseminated to policy-makers and participating communities.

Eggs for Improving Nutrition, cognitive development and reducing linear growth retardation among Infants and young Children (ENRICH): protocol of an egg supplementation trial among children aged 9-18 months in Hyderabad, India.

INTRODUCTION: Evidence on the impact of nutrient-rich animal source foods such as eggs for improving child growth and cognition is inconsistent. This study aims to examine the impact of an egg intervention in children, along with behaviour change communication (BCC) to the mother, on linear growth and cognition, and nutritional status in children aged 9-18 months. METHODS AND ANALYSIS: A 9-month open-labelled randomised controlled trial will be conducted in three urban slums in Hyderabad, India, as a substudy of an observational cohort study (n=350) following pregnant women and their children until 18 months of age in a population at risk of stunting. The children born to women enrolled during the third trimester of pregnancy will be block randomised in a 1:4 ratio into the intervention (n=70) and control (n=280) groups. Children in the intervention group will be supplemented with one egg per day starting from 9 months until 18 months of age. BCC designed to enhance adherence to the intervention will be used. The control group will be a part of the observational cohort and will not receive any intervention from the study team. The primary outcome will be length-for-age z-scores, and the secondary outcomes will include cognition, blood biomarkers of nutritional status including fatty acid profile and epigenetic signatures linked with linear growth and cognition. Multivariate intention-to-treat analyses will be conducted to assess the effect of the intervention. ETHICS AND DISSEMINATION: The study is approved by the Institutional ethics committees of ICMR-National Institute of Nutrition, Hyderabad, India and London School of Hygiene and Tropical Medicine, UK. The results will be published in peer-reviewed journals and disseminated to policy-makers. Findings will also be shared with study participants and community leaders. TRIAL REGISTRATION NUMBER: CTRI/2021/11/038208.

Measurement of cognition and profiling early learning environments in India, Indonesia and Senegal: a UKRI GCRF Action Against Stunting Hub protocol paper.

INTRODUCTION: Childhood stunting is associated with poorer child health, growth and development including diminished cognitive abilities. Mapping out the links between child stunting and Early Childhood Education and Development is critical to increasing understanding of the causes and effects of childhood stunting, and for programme and policy development. The aim of this study is to investigate and compare the development and educational environments across India, Indonesia and Senegal, and to identify the multifactorial drivers and impacts of childhood stunting to inform a new typology. METHODS AND ANALYSIS: This current study is part of an interdisciplinary observational research study, where women are recruited during pregnancy and mother-infant pairs followed prospectively, up to 24 months after birth. Eight measures will be used to profile children's early development and learning environments in two sample cohorts: (A) children aged 12 and 24 months born to the women recruited during pregnancy (ie, 500 pregnant mothers per country) and (B) a preschool case-control cohort of siblings from the main cohort aged between 3:6 and 5:6 years of age where anthropomorphic measures will be collected to assess degrees of stunting. Profiling of the development and learning environments in the countries will include both parent/caregiver self-reported and local staff (enumerators) direct assessments of children and settings. ETHICS AND DISSEMINATION: This study was approved by the institutional ethics committees of all partner institutions. In India, Indian Council of Medical Research-National Institute of Nutrition, Hyderabad; In Indonesia, Ethics Committee of the Faculty of Medicine, University of Indonesia; and in Senegal, National Ethics Committee for Scientific Research in Senegal.The findings of the study will be disseminated in national and international meetings, seminars, conferences and peer-reviewed journals.

A Randomized Multiple Micronutrient Powder Point-of-Use Fortification Trial Implemented in Indian Preschools Increases Expressive Language and Reduces Anemia and Iron Deficiency.

BACKGROUND: Anemia is a global public health problem that undermines childhood development. India provides government-sponsored integrated nutrition/child development preschools. OBJECTIVES: This double-masked, cluster-randomized controlled trial examines whether point-of-use multiple micronutrient powder (MNP) compared with placebo fortification of preschool meals impacts child development and whether effects vary by preschool quality (primary outcome) and biomarkers of anemia and micronutrients (secondary outcomes). We also measured growth and morbidity. METHODS: We randomly assigned 22 preschools in rural India to receive MNP/placebo fortification. We administered baseline and endline blood sampling and measures of childhood development (Mullen Scales of Early Learning, inhibitory control, social-emotional), anthropometry, and morbidity to preschoolers (aged 29-49 mo). Preschools added MNP/placebo to meals 6 d/wk for 8 mo. We conducted linear mixed-effects regression models accounting for preschool clustering and repeated measures. We evaluated child development, examining effects in high- compared with low-quality preschools using the Early Childhood Environment Rating Scale-Revised and the Home Observation for the Measurement of the Environment Inventory, modified for preschools. RESULTS: At baseline, mean age ± SD was 36.6 ± 5.7 mo, with 47.8% anemic, 41.9% stunted, and 20.0% wasted. Baseline expressive/receptive language scores were higher in high-quality compared with low-quality preschools (P = 0.02 and P = 0.03, respectively). At endline (91% retention, n = 293/321), we found MNP compared with placebo effects in expressive language (Cohen's standardized effect d = 0.4), inhibitory control (d = 0.2), and social-emotional (d = 0.3) in low-quality, not high-quality, preschools. MNP had significantly greater reduction of anemia and iron deficiency compared with placebo (37% compared with 13.5% and 41% compared with 1.2%, respectively). There were no effects on growth or morbidity. CONCLUSIONS: Providing multiple micronutrient-fortified meals in government-sponsored preschools is feasible; reduced anemia and iron deficiency; and, in low-quality preschools, increased preschoolers' expressive language and inhibitory control and reduced developmental disparities. Improving overall preschool quality by incorporating multiple components of nurturing care (responsive care, learning, and nutrition) may be necessary to enhance preschoolers' development. This trial was registered at clinicaltrials.gov as NCT01660958.

Guava with an institutional supplementary meal improves iron status of preschoolers: a cluster-randomized controlled trial.

The Integrated Child Development Services of India provides Supplementary Nutrition Program (SNP) to preschoolers. Using this platform, the current study examined the impact of diversifying a cereal/pulse-based SNP-meal with guava on iron status and cognitive development among 24-48 months old children. A three-arm, nonblinded, cluster-randomized controlled trial (CTRI/2014/09/004983) included 399 beneficiaries from 28 preschools in 16 villages in Telangana state, India. The villages were randomly assigned to receive 25 g of guava (guava group (GG)), banana (banana group (BG)), or cucumber (cucumber group (CG)) along with a SNP meal for 140 days. Nutrient biomarkers (iron status, plasma vitamin C, vitamin B12 , and folate), cognitive development, anthropometric indicators (WAZ, HAZ, and WHZ), and morbidity were assessed at baseline and endline. A linear mixed model and a generalized estimating equation were applied to compare changes in outcomes across the groups. All outcome variables were comparable across groups at baseline. The iron to vitamin C molar ratio improved in the GG from 1:1.4 to 1:12 but remained unaltered in control groups. Higher hemoglobin (P = 0.002), serum ferritin (SF; P < 0.001), vitamin C (P = 0.047), and lower soluble transferrin receptor (sTfR; P < 0.001) causing decreased prevalence of iron deficiency (ID) (P = 0.003) were observed in the GG compared with BG and CG. Prevalence of acute respiratory infection (ARI) was lower in the GG (P = 0.035) versus controls. No impact was observed on cognitive development or growth. Thus, diversifying a cereal/pulse-based meal with guava increased meal vitamin C content, thereby reducing ID and ARI-related morbidity. This approach represents a valid and scalable strategy to address ID among young children.

A complementary feeding and play intervention improves the home environment and mental development among toddlers in rural India.

A cluster randomized trial design was used to test the efficacy of a behaviour change communication intervention on the quality of the home environment and infant development at 15 months of age. Children (n = 600) in rural South India were followed from 3 through 15 months of age. The control group (C group) received the standard of care, the complementary feeding group (CF group) received recommendations on complementary foods and the responsive complementary feeding and play group (RCF&P group) received recommendations on complementary foods plus skills on responsive feeding and play. The intervention was delivered in biweekly home visits to caregivers using flip charts. At postintervention, infants (n = 521) were assessed for development (Bayley-II scales) and their home environment was assessed (Home Observation for Measurement of the Environment [HOME] scale). Cluster adjusted analysis of variance showed no significant differences at baseline. The HOME score at 15 months differed by group, F(2, 38) = 6.41, P = 0.004; the CF and RCF&P groups had higher scores than the C group. Scores on subscales 'Opportunities for Variety in Daily Stimulation' and 'Caregiver Promotion of Child Development' (CPCD) were higher for the RCF&P group than for the C and CF groups. Mental development index (MDI) scores differed by group, F(2, 37) = 3.31, P = 0.04, with the RCF&P group showing higher scores than the C group (P < 0.04); no differences were noted in psychomotor development index (PDI) scores (P = 0.48). The subscales of HOME associated with MDI at 15 months were 'CPCD' and 'Cleanliness of Child' (R2 = 0.076). 'CPCD' was also associated with PDI (R2 = 0.039). A responsive complementary feeding and play intervention delivered through home visits benefitted children's mental development and caregiving environment at 15 months.

Mechanisms linking height to early child development among infants and preschoolers in rural India.

Stunting has been negatively associated with children's development. We examined the range of height by testing hypotheses: (a) height is positively associated with children's development, with associations moderated by inflammation and (b) home environments characterized by nurturance and early learning opportunities is positively associated with children's development over time and attenuate associations with height. Data included 513 infants (mean age 8.6 months) and 316 preschoolers (mean age 36.6 months) in rural India from a randomized controlled trial of multiple micronutrient powders (MNPs). Measures included height (height-for-age z-scores based on WHO standards), inflammation (C-reactive protein concentration >5 mg/L), nurturance (HOME Inventory), child development (Mullens Scales of Early Learning), and inhibitory control (preschoolers). Linear mixed effects models accounting for repeated measures, clustering, and confounders were used to assess associations between height and child development over time (infants: enrollment, 6 and 12 months; preschoolers: enrollment and 8 months). Moderating effects of inflammation and nurturance were tested with interaction terms. Among infants and preschoolers, height and nurturance were positively associated with all domains of child development over time, with the exception of inhibitory control. Among preschoolers, in the presence of inflammation, height was not associated with child development. Among infants, but not preschoolers, a nurturant home environment attenuated significant associations between height with fine motor and receptive language development. The mechanisms associated with children's development over time are multifactorial and include direct and indirect associations among nutrition, health, and the home environment, as supported by the Nurturing Care Framework.

A food synergy approach in a national program to improve the micronutrient status of preschoolers: a randomized control trial protocol.

Iron deficiency anemia (IDA) is a significant public health issue in India affecting nearly all vulnerable segments of the population. Causes of IDA include low consumption of iron-rich foods combined with poor iron bioavailability of nonheme iron sources. To date, interventions aimed at correcting IDA focus on increasing iron intake through iron supplementation or fortification strategies. In contrast, dietary diversification is a long-term sustainable approach to improve bioavailable iron intake. In this context, the inclusion of vitamin C-rich fruits in the regular diet has proven to improve iron absorption, but the effect on iron status is inconclusive. Considering the ongoing national program for preschoolers in India, we designed a cluster randomized controlled trial (RCT) to test the hypothesis that inclusion of vitamin C-rich fruit in a regular meal would improve iron absorption and lead to better child iron and micronutrient status, cognitive development, gut health, and growth while reducing morbidity. This paper illustrates a context-specific framework and activities to design and functionalize an open-label, three-arm cluster RCT to test a specific hypothesis. The results of this designed trial should generate evidence to inform policy on the effect of a food-based intervention on iron status.

Do socio-economic inequalities in infant growth in rural India operate through maternal size and birth weight?

BACKGROUND: In total, 3.1 million young children die every year from under-nutrition. Greater understanding of associations between socio-economic status (SES) and the biological factors that shape under-nutrition are required to target interventions. AIM: To establish whether SES inequalities in under-nutrition, proxied by infant size at 12 months, operate through maternal and early infant size measures. SUBJECTS AND METHODS: The sample comprised 347 Indian infants born in 60 villages in rural Andhra Pradesh 2005-2007. Structural equation path models were applied to decompose the total relationship between SES (standard of living index) and length and weight for age Z-scores (LAZ/WAZ) at 12 months into direct and indirect (operating through maternal BMI and height, birthweight Z-score and LAZ/WAZ at 6 months) paths. RESULTS: SES had a direct positive association with LAZ (Standardised coefficient = 0.08, 95% CI = 0.02-0.13) and WAZ at age 12 months (Standardised coefficient = 0.08, 95% CI = 0.02-0.15). It also had additional indirect positive associations through increased maternal height and subsequently increased birthweight and WAZ/LAZ at 6 months, accounting for 35% and 53% of the total effect for WAZ and LAZ, respectively. CONCLUSION: Findings support targeting evidence based growth interventions towards infants from the poorest families with the shortest mothers. Increasing SES can improve growth for two generations.

Characterisation of anaemia and associated factors among infants and pre-schoolers from rural India.

OBJECTIVE: In India, national databases indicate anaemia prevalence of 80 % among 6-35-month-old children and 58 % among 36-59-month-old children. The present study aimed to characterise anaemia and the associated factors among infants and pre-schoolers living in rural India. DESIGN: Multivariate logistic regression analysis of data collected prior to an intervention trial. Fe-deficiency with anaemia (IDA), Fe deficiency with no anaemia (IDNA) and anaemia without Fe deficiency were defined. Serum ferritin, soluble transferrin receptor (sTfR) and sTfR/log ferritin index were used to indicate Fe status. SETTING: Twenty-six villages of Nalgonda district, Telangana, India. Data were collected in community sites. Participants Four hundred and seventy-six infants (aged 6-12 months), 316 pre-schoolers (aged 29-56 months) and their mothers. RESULTS: Prevalence of anaemia among infants and pre-schoolers was 66·4 and 47·8 %, prevalence of IDA was 52·2 and 42·1 %, prevalence of IDNA was 22·2 and 29·8 %, prevalence of anaemia without Fe deficiency was 14·2 and 5·7 %. Among infants, anaemia was positively associated with maternal anaemia (OR=3·31; 95 % CI 2·10, 5·23; P<0·001), and sTfR/log ferritin index (OR=2·21; 95 % CI 1·39, 3·54; P=0·001). Among pre-schoolers, anaemia was positively associated with maternal anaemia (OR=3·77; 95 % CI 1·94, 7·30; P<0·001), sTfR/log ferritin index (OR=5·29; 95 % CI 2·67, 10·50; P<0·001), high C-reactive protein (OR=4·39; 95 % CI 1·91, 10·06, P<0·001) and young age (29-35 months: OR=1·92; 05 % CI 1·18, 3·13, P=0·009). CONCLUSIONS: Anaemia prevalence continues to be high among infants and pre-schoolers in rural India. Based on sTfR/ferritin index, Fe deficiency is a major factor associated with anaemia. Anaemia is also associated with inflammation among pre-schoolers and with maternal anaemia among infants and pre-schoolers, illustrating the importance of understanding the aetiology of anaemia in designing effective control strategies.

Formative research methods for designing culturally appropriate, integrated child nutrition and development interventions: an overview.

Nutritional and developmental insults in the first few years of life have profound public health implications, including substantial contributions to neonatal, infant, and early childhood morbidity and mortality, as well as longer term effects on cognitive development, school achievement, and worker productivity. Optimal development that can lead to the attainment of an individual's fullest potential, therefore, requires a combination of genetic capacity, adequate nutrition, psychosocial stimulation, and safe, clean physical environments. Researchers and policymakers have called for integrated child nutrition and development interventions for more than 20 years, yet there are only a handful of efficacy trials and even fewer examples of integrated interventions that have been taken to scale. While a critical component in the design of such interventions is formative research, there is a dearth of information in both the literature and policy arenas to guide this phase of the process. To move the field forward, this paper first provides an overview of formative research methods with a focus on qualitative inquiry, a description of the critical domains to be assessed (infant and young child feeding, responsive feeding, and child development), and currently available resources. Application of these methods is provided through a real-world case study--the design of an integrated nutrition and child development efficacy trial in Andhra Pradesh, India. Recommendations for next steps are discussed, the most important of which is the need for a comprehensive set of formative guidelines for designing locally tailored, culturally appropriate, integrated interventions.

Integrating nutrition and early child-development interventions among infants and preschoolers in rural India.

This article describes the development, design, and implementation of an integrated randomized double-masked placebo-controlled trial (Project Grow Smart) that examines how home/preschool fortification with multiple micronutrient powder (MNP) combined with an early child-development intervention affects child development, growth, and micronutrient status among infants and preschoolers in rural India. The 1-year trial has an infant phase (enrollment age: 6-12 months) and a preschool phase (enrollment age: 36-48 months). Infants are individually randomized into one of four groups: placebo, placebo plus early learning, MNP alone, and MNP plus early learning (integrated intervention), conducted through home visits. The preschool phase is a cluster-randomized trial conducted in Anganwadi centers (AWCs), government-run preschools sponsored by the Integrated Child Development System of India. AWCs are randomized into MNP or placebo, with the MNP or placebo mixed into the children's food. The evaluation examines whether the effects of the MNP intervention vary by the quality of the early learning opportunities and communication within the AWCs. Study outcomes include child development, growth, and micronutrient status. Lessons learned during the development, design, and implementation of the integrated trial can be used to guide large-scale policy and programs designed to promote the developmental, educational, and economic potential of children in developing countries.

Cluster-randomized trial on complementary and responsive feeding education to caregivers found improved dietary intake, growth and development among rural Indian toddlers.

Inadequate feeding and care may contribute to high rates of stunting and underweight among children in rural families in India. This cluster-randomized trial tested the hypothesis that teaching caregivers appropriate complementary feeding and strategies for how to feed and play responsively through home-visits would increase children's dietary intake, growth and development compared with home-visit-complementary feeding education alone or routine care. Sixty villages in Andhra Pradesh were randomized into three groups of 20 villages with 200 mother-infant dyads in each group. The control group (CG) received routine Integrated Child Development Services (ICDS); the complementary feeding group (CFG) received the ICDS plus the World Health Organization recommendations on breastfeeding and complementary foods; and the responsive complementary feeding and play group (RCF&PG) received the same intervention as the CFG plus skills for responsive feeding and psychosocial stimulation. Both intervention groups received bi-weekly visits by trained village women. The groups did not differ at 3 months on socioeconomic status, maternal and child nutritional indices, and maternal depression. After controlling for potential confounding factors using the mixed models approach, the 12-month intervention to the CFG and RCF&PG significantly (P < 0.05) increased median intakes of energy, protein, Vitamin A, calcium (CFG), iron and zinc, reduced stunting [0.19, confidence interval (CI): 0.0-0.4] in the CFG (but not RCF&PG) and increased (P < 0.01) Bayley Mental Development scores (mean = 3.1, CI: 0.8-5.3) in the RCF&PG (but not CFG) compared with CG. Community-based educational interventions can improve dietary intake, length (CFG) and mental development (RCF&PG) for children under 2 years in food-secure rural Indian families.

Using the WHO 2006 child growth standard to assess the growth and nutritional status of rural south Indian infants.

BACKGROUND: The WHO 2006 child growth standard is advocated in India, although the conformity of the growth of Indian infants to the WHO standard has only been assessed at cross-sectional points. AIM: To assess the implications of using the WHO standard in rural India and to investigate the factors responsible for any departure from optimal growth, as shown in the WHO standard. SUBJECTS AND METHODS: Mixed-effects models were applied to serial weight and length data from 384 rural south Indian infants. Unadjusted and adjusted (for, among other things, breastfeeding and maternal education) estimates were converted to Z-scores and the risks of underweight, wasting and stunting using the WHO standard compared to the NCHS 1977 child growth reference were calculated. RESULTS: Weight growth was more similar to the WHO standard than the NCHS reference and in late infancy the WHO standard was less likely to classify underweight (RR at 15 months = 0.45; 95% CI = 0.31-0.65). Adjusting the serial data shifted the curves 0.25 Z-scores closer to the median of either chart; variations in household socioeconomic status and morbidity were largely responsible for this shift. CONCLUSION: In late infancy, the WHO standard will allow a more focused intervention effort and use of resources for targeting programmes at infants most at risk of malnutrition.

Psychometric validation of a knowledge questionnaire on micronutrients among adolescents and its relationship to micronutrient status of 15-19-year-old adolescent boys, Hyderabad, India.

OBJECTIVE: To develop a psychometrically valid questionnaire for testing knowledge on micronutrients and to assess the relationship between knowledge and biomarkers of micronutrient status among adolescents. DESIGN: Cross-sectional, institution-based, validity and reliability study. SETTING: Seven higher secondary schools were covered in the limits of Greater Hyderabad Municipal Corporation, Hyderabad, India. SUBJECTS: Students aged 15-19 years, n 92 for the pre-test, n 108 for test-retest and n 109 for studying the relationship between knowledge and biomarkers of Fe, retinol, ascorbic acid, α-tocopherol, folic acid and vitamin B12 status. RESULTS: From an item pool of 106, thirty-one items were selected based on content validity. Statistical tools to obtain a valid and reliable questionnaire among adolescent boys and girls resulted in eighteen items with a difficulty index of 0·11-0·86, discrimination index of 0·20-0·72 and validity index (point bi-serial correlation) of 0·10-0·62. Reliability as measured by Cronbach's α was 0·71 and the intra-class correlation coefficient was 0·80. A Bland-Altman plot showed good agreement between test and retest scores. The mean response score to the eighteen-item questionnaire was 5·2 (sd 2·68). The mean values of serum retinol were significantly different (P = 0·022) between groups below (24·8 (sd 6·64) µg/dl) and above (28·0 (sd 7·67) µg/dl) the 50th percentile of knowledge score. The relationship persisted after controlling for economic status as a covariate using analysis of covariance (P = 0·018). Other micronutrients did not show any significant relationship. CONCLUSIONS: A valid and reliable eighteen-item knowledge questionnaire was constructed and found to have a significant positive relationship with plasma retinol status alone.