Correction to: Effects of early feeding on growth velocity and overweight/obesity in a cohort of HIV unexposed South African infants and children.

[This corrects the article DOI: 10.1186/s13006-015-0041-x.].

Effects of an exclusive breastfeeding intervention for six months on growth patterns of 4-5 year old children in Uganda: the cluster-randomised PROMISE EBF trial.

BACKGROUND: Breastfeeding promotion is regarded as one of the most effective interventions to improve child health, and could reduce under-5-mortality by 8 % globally. Few studies have assessed the health outcomes beyond infancy of interventions promoting exclusive breastfeeding. METHODS: This study assessed growth in under-five children who participated in a cluster-randomised trial in Eastern Uganda (ClinicalTrials.gov.no.NCT00397150). In the intervention arm, peer counsellors promoted exclusive breastfeeding during the first 6 months of infancy. There were no interventions after 6 months of age. Mother-infant pairs were interviewed at visits scheduled at 3, 6, 12 and 24 weeks after birth and follow-up visits at 2 and 5 years, with 765 included in the analyses. RESULTS: The mean length/height-for-age and weight-for-age-z-score (HAZ, WAZ) decreased with increasing age in both the intervention and control arms. At the three weeks visit, HAZ in the intervention was -0.45 (-0.68;-0.21) and -0.32 (-0.56;-0.07) in the control arm. At the 2 year follow-up, the mean HAZ in the intervention was -1.85 (95 % CI -1.97;-1.73) compared to -1.61 (-1.87;-1.34) in the control. Similarly, at the 5 year follow-up, the mean HAZ in the intervention was -1.78 (-2.08;-1.47) compared to -1.53 (-1.79;-1.28) in the control arm. At the 2 year follow-up visit, 139 (45 %) were stunted (HAZ<-2) in the intervention compared to 109 (37 %) in the control arm, odds ratio (OR) 1.7 (1.1;2.4). Underweight (WAZ<-2) was also more common in the intervention arm than in the control at the five years follow-up (OR 1.7 (1.0;2.8)), with a mean WAZ of -1.28 (-1.47;-1.08) and -1.06 (-1.19;-0.92) in the intervention and control arm, respectively. CONCLUSION: While stunting was widespread at 2 and 5 years of age in both arms, it was more common in the intervention arm. It is questionable whether community-based support from lay people with short training and focussing only on exclusive breastfeeding, is an appropriate strategy to improve child health and development. TRIAL REGISTRATION: ClinicalTrials.gov.no. NCT00397150 . Registered 7th of November 2006.

Objectively Assessed Physical Activity and Associated Factors Among Adults in Peri-Urban and Rural Eastern Uganda: A Population-based Study.

BACKGROUND: Data on physical inactivity, a known risk factor for noncommunicable diseases and its correlates in sub-Saharan Africa are almost absent. We assessed physical activity patterns and associated factors among adults. METHODS: A populationbased study of 1208 adults was conducted in the Iganga-Mayuge Health and Demographic Surveillance Site, Uganda. Physical activity was assessed using a pedometer for 7 days. Physical inactivity was defined as a daily average of < 7500 steps while sedentary behavior was defined as a daily average of < 5000 steps. Logistic regression was conducted to identify factors associated with physical inactivity and sedentary behavior. RESULTS: Of the 1208 participants, 18.8% were sedentary (10.6% of men; 26.9% of women, P < .001), 37.6% were physically inactive (28.5% of men; 46.6% of women, P < .001). Factors associated with sedentary behavior were being female, ≥ 65 years, peri-urban residence, being a domestic worker, formal employment and lower primary education. Factors associated with physical inactivity were being female, 55 to 64 years, ≥ 65 years, peri-urban residence, overweight and obesity. CONCLUSIONS: Sedentary behavior and physical inactivity were prevalent among the adult population. Targeted physical activity promotion interventions are needed.

Using growth velocity to predict child mortality.

BACKGROUND: Growth assessment based on the WHO child growth velocity standards can potentially be used to predict adverse health outcomes. Nevertheless, there are very few studies on growth velocity to predict mortality. OBJECTIVES: We aimed to determine the ability of various growth velocity measures to predict child death within 3 mo and to compare it with those of attained growth measures. DESIGN: Data from 5657 children <5 y old who were enrolled in a cohort study in the Democratic Republic of Congo were used. Children were measured up to 6 times in 3-mo intervals, and 246 (4.3%) children died during the study period. Generalized estimating equation (GEE) models informed the mortality risk within 3 mo for weight and length velocity z scores and 3-mo changes in midupper arm circumference (MUAC). We used receiver operating characteristic (ROC) curves to present balance in sensitivity and specificity to predict child death. RESULTS: GEE models showed that children had an exponential increase in the risk of dying with decreasing growth velocity in all 4 indexes (1.2- to 2.4-fold for every unit decrease). A length and weight velocity z score of <-3 was associated with an 11.8- and a 7.9-fold increase, respectively, in the RR of death in the subsequent 3-mo period (95% CIs: 3.9, 35.5, and 3.9, 16.2, respectively). Weight and length velocity z scores had better predictive abilities [area under the ROC curves (AUCs) of 0.67 and 0.69] than did weight-for-age (AUC: 0.57) and length-for-age (AUC: 0.52) z scores. Among wasted children (weight-for-height z score <-2), the AUC of weight velocity z scores was 0.87. Absolute MUAC performed best among the attained indexes (AUC: 0.63), but longitudinal assessment of MUAC-based indexes did not increase the predictive value. CONCLUSION: Although repeated growth measures are slightly more complex to implement, their superiority in mortality-predictive abilities suggests that these could be used more for identifying children at increased risk of death.

Population-based survey of overweight and obesity and the associated factors in peri-urban and rural Eastern Uganda.

BACKGROUND: In sub-Saharan Africa (SSA), the rising prevalence of overweight, obesity and non-communicable diseases co-exists with the high burden of under-nutrition. The paucity of data on adulthood overweight and obesity, disaggregated by socio-demographic characteristics and in rural settings in SSA calls for research. We determined the prevalence of underweight, overweight/obesity and associated factors among adults in peri-urban and rural Uganda. METHODS: A cross-sectional study of 1210 randomly selected adults aged ≥ 18 years was conducted in Iganga-Mayuge Health and Demographic Surveillance Site in eastern Uganda in 2013. Height, weight and socio-demographic variables were assessed. Overweight was defined as BMI = 25.0-29.99 kg/m(2), obesity ≥ 30 kg/m(2) and overweight/obesity ≥ 25 kg/m(2). Logistic regression was used to identify factors associated with overweight/obesity. RESULTS: Of the participants, 7 % were underweight (8.1 % of men; 5.9 % of women, p = 0.99); 17.8 % were overweight (12.4 % of men; 23.1 % of women, p < 0.001); and 7 % were obese (2.0 % of men; 12.7 % of women, p < 0.001). Overweight prevalence was 15.8 % and 23.8 % among rural and peri-urban adults, respectively (p < 0.001). Obesity prevalence was 3.9 % and 17.8 % among rural and peri-urban adults, respectively (p < 0.001). Factors associated with overweight/obesity were: being female, adjusted odds ratio (AOR) 4.3 (95 % confidence interval (PloS one 8:e75640, 20013) 3.2-5.9); peri-urban residence AOR 2.6 (1.9-3.6); being in age group 35-44, AOR 3.1 (1.8-5.3); 45-54 AOR 4.1 (2.3-7.3); 55-64 AOR 2.6 (1.4-5.0); ≥ 65 years AOR 3.1 (1.6-6.0); and having socio-economic status (SES) in the third AOR 2.8 (1.7-4.6), fourth 2.5 (1.5-4.2) and fifth 2.7 (1.6-4.4) quintile. CONCLUSIONS: Overweight/obesity was prevalent among adults. Overweight/obese was associated with being female, being aged 35 years and older, residing in a peri-urban area and having a higher SES. The time has come to develop interventions to prevent and control overweight/obesity.

Optimal central obesity measurement site for assessing cardiometabolic and type 2 diabetes risk in middle-aged adults.

OBJECTIVES: Despite recommendations that central obesity assessment should be employed as a marker of cardiometabolic health, no consensus exists regarding measurement protocol. This study examined a range of anthropometric variables and their relationships with cardiometabolic features and type 2 diabetes in order to ascertain whether measurement site influences discriminatory accuracy. In particular, we compared waist circumference (WC) measured at two sites: (1) immediately below the lowest rib (WC rib) and (2) between the lowest rib and iliac crest (WC midway), which has been recommended by the World Health Organisation and International Diabetes Federation. MATERIALS AND METHODS: This was a cross-sectional study involving a random sample of 2,002 men and women aged 46-73 years. Metabolic profiles and WC, hip circumference, pelvic width and body mass index (BMI) were determined. Correlation, logistic regression and area under the receiver operating characteristic curve analyses were used to evaluate obesity measurement relationships with metabolic risk phenotypes and type 2 diabetes. RESULTS: WC rib measures displayed the strongest associations with non-optimal lipid and lipoprotein levels, high blood pressure, insulin resistance, impaired fasting glucose, a clustering of metabolic risk features and type 2 diabetes, in both genders. Rib-derived indices improved discrimination of type 2 diabetes by 3-7% compared to BMI and 2-6% compared to WC midway (in men) and 5-7% compared to BMI and 4-6% compared to WC midway (in women). A prediction model including BMI and central obesity displayed a significantly higher area under the curve for WC rib (0.78, P=0.003), Rib/height ratio (0.80, P<0.001), Rib/pelvis ratio (0.79, P<0.001), but not for WC midway (0.75, P=0.127), when compared to one with BMI alone (0.74). CONCLUSIONS: WC rib is easier to assess and our data suggest that it is a better method for determining obesity-related cardiometabolic risk than WC midway. The clinical utility of rib-derived indices, or alternative WC measurements, deserves further investigation.

The social context of severe child malnutrition: a qualitative household case study from a rural area of the Democratic Republic of Congo.

INTRODUCTION: The magnitude of child malnutrition including severe child malnutrition is especially high in the rural areas of the Democratic Republic of Congo (the DRC). The aim of this qualitative study is to describe the social context of malnutrition in a rural part of the DRC and explore how some households succeed in ensuring that their children are well-nourished while others do not. METHODOLOGY: This study is based on participant observation, key informant interviews, group discussions and in-depth interviews with four households with malnourished children and four with well-nourished children. We apply social field theory to link individual child nutritional outcomes to processes at local level and to the wider socio-economic environment. FINDINGS: We identified four social fields that have implications for food security and child nutritional outcomes: 1) household size and composition which determined vulnerability to child malnutrition, 2) inter-household cooperation in the form of 'gbisa work party' which buffered scarcity of labour in peak seasons and facilitated capital accumulation, 3) the village associated with usufruct rights to land, and 4) the local NGO providing access to agricultural support, clean drinking water and health care. CONCLUSIONS: Households that participated in inter-household cooperation were able to improve food and nutrition security. Children living in households with high pressure on productive members were at danger of food insecurity and malnutrition. Nutrition interventions need to involve local institutions for inter-household cooperation and address the problem of social inequalities in service provision. They should have special focus on households with few resources in the form of land, labour and capital.

Effects of early feeding on growth velocity and overweight/obesity in a cohort of HIV unexposed South African infants and children.

BACKGROUND: South Africa has the highest prevalence of overweight/obesity in Sub-Saharan Africa. Assessing the effect of modifiable factors such as early infant feeding on growth velocity and overweight/obesity is therefore important. This paper aimed to assess the effect of infant feeding in the transitional period (12 weeks) on 12-24 week growth velocity amongst HIV unexposed children using WHO growth velocity standards and on the age and sex adjusted body mass index (BMI) Z-score distribution at 2 years. METHODS: Data were from 3 sites in South Africa participating in the PROMISE-EBF trial. We calculated growth velocity Z-scores using the WHO growth standards and assessed feeding practices using 24-hour and 7-day recall data. We used quantile regression to study the associations between 12 week infant feeding and 12-24 week weight velocity (WVZ) with BMI-for-age Z-score at 2 years. We included the internal sample quantiles (70th and 90th centiles) that approximated the reference cut-offs of +2 (corresponding to overweight) and +3 (corresponding to obesity) of the 2 year BMI-for-age Z-scores. RESULTS: At the 2-year visit, 641 children were analysed (median age 22 months, IQR: 17-26 months). Thirty percent were overweight while 8.7% were obese. Children not breastfed at 12 weeks had higher 12-24 week mean WVZ and were more overweight and obese at 2 years. In the quantile regression, children not breastfed at 12 weeks had a 0.37 (95% CI 0.07, 0.66) increment in BMI-for-age Z-score at the 50th sample quantile compared to breast-fed children. This difference in BMI-for-age Z-score increased to 0.46 (95% CI 0.18, 0.74) at the 70th quantile and 0.68 (95% CI 0.41, 0.94) at the 90th quantile . The 12-24 week WVZ had a uniform independent effect across the same quantiles. CONCLUSIONS: This study demonstrates that the first 6 months of life is a critical period in the development of childhood overweight and obesity. Interventions targeted at modifiable factors such as early infant feeding practices may reduce the risks of rapid weight gain and subsequent childhood overweight/obesity.

Diet and kwashiorkor: a prospective study from rural DR Congo.

The etiology of kwashiorkor remains enigmatic and longitudinal studies examining potential causes of kwashiorkor are scarce. Using historical, longitudinal study data from the rural area of Bwamanda, Democratic Republic of Congo, we investigated the potential causal association between diet and the development of kwashiorkor in 5 657 preschool children followed 3-monthly during 15 months. We compared dietary risk factors for kwashiorkor with those of marasmus. Kwashiorkor was diagnosed as pitting oedema of the ankles; marasmus as abnormal visibility of skeletal structures and palpable wasting of the gluteus muscle. A 24-h recall was administered 3-monthly to record the consumption of the 41 locally most frequent food items. We specified Hanley-Miettinen smooth-in-time risk models containing potential causal factors, including food items, special meals prepared for the child, breastfeeding, disease status, nutritional status, birth rank, age, season and number of meals. Bayesian Information Criteria identified the most plausible causal model of why some children developed kwashiorkor. In a descriptive analysis of the diet at the last dietary assessment prior to development of kwashiorkor, the diet of children who developed kwashiorkor was characterized by low consumption of sweet potatoes, papaya and "other vegetables" [0.0% , 2.3% (95% CI [0.4, 12.1]) and 2.3% (95% CI [0.4, 12.1])] in comparison with children who did not develop kwashiorkor [6.8% (95% CI [6.4, 7.2]), 15.5% (95% CI [15, 16.1]) and 15.1% (95% CI [14.6, 15.7])] or children who developed marasmus [4.5% (95% CI [2.6, 7.5]) 11.8% (95% CI [8.5, 16.0]) and 17.6% (95% CI [13.7, 22.5])]. Sweet potatoes and papayas have high ß-carotene content and so may some of "the other vegetables". We found that a risk model containing an age function, length/height-for age Z-score, consumption of sweet potatoes, papaya or other vegetables, duration of this consumption and its interaction term, was the most plausible model. Among children aged 10-42 months, the risk of developing kwashiorkor increased with longer non-consumption of these foods. The analysis was repeated with only children who developed marasmus as the reference series, yielding similar results. Our study supports that ß-carotene may play an important role in the protection against kwashiorkor development.

Incidence and course of child malnutrition according to clinical or anthropometrical assessment: a longitudinal study from rural DR Congo.

BACKGROUND: Longitudinal studies describing incidence and natural course of malnutrition are scarce. Studies defining malnutrition clinically [moderate clinical malnutrition (McM) marasmus, kwashiorkor] rather than anthropometrically are rare. Our aim was to address incidence and course of malnutrition among pre-schoolers and to compare patterns and course of clinically and anthropometrically defined malnutrition. METHODS: Using a historical, longitudinal study from Bwamanda, DR Congo, we studied incidence of clinical versus anthropometrical malnutrition in 5,657 preschool children followed 3-monthly during 15 months. RESULTS: Incidence rates were highest in the rainy season for all indices except McM. Incidence rates of McM and marasmus tended to be higher for boys than for girls in the dry season. Malnutrition rates increased from the 0-5 to the 6 - 11 months age category. McM and marasmus had in general a higher incidence at all ages than their anthropometrical counterparts, moderate and severe wasting. Shifts back to normal nutritional status within 3 months were more frequent for clinical than for anthropometrical malnutrition (62.2-80.3% compared to 3.4-66.4.5%). Only a minority of moderately stunted (30.9%) and severely stunted children (3.4%) shifted back to normal status. Alteration from severe to mild malnutrition was more characteristic for anthropometrically than for clinically defined malnutrition. CONCLUSIONS: Our data on age distribution of incidence and course of malnutrition underline the importance of early life intervention to ward off malnutrition. In principle, looking at incidence may yield different findings from those obtained by looking at prevalence, since incidence and prevalence differ approximately differ by a factor "duration". Our findings show the occurrence dynamics of general malnutrition, demonstrating that patterns can differ according to nutritional assessment method. They suggest the importance of applying a mix of clinical and anthropometric methods for assessing malnutrition instead of just one method. Functional validity of characterization of aspects of individual nutritional status by single anthropometric scores or by simple clinical classification remain issues for further investigation.

HIV infection, viral load, low birth weight, and nevirapine are independent influences on growth velocity in HIV-exposed South African infants.

Data from a prospective multisite cohort study were used to examine the effect of HIV exposure, untreated HIV infection, and single-dose nevirapine on infant growth velocity. The 2009 WHO growth velocity standards constitute a new tool for this type of investigation and are in need of functional validation. In period 1 (3-24 wk), 65 HIV-infected, 502 HIV-exposed uninfected (HEU), and 216 HIV-unexposed infants were included. In period 2 (25-36 wk), 31 infants moved from the HEU group to the HIV-infected group. We compared weight velocity Z-scores (WVZ) and length velocity Z-scores (LVZ) by HIV group and assessed their independent influences. In period 1, mean WVZ (95% CI) was significantly (P < 0.001) lower in infected [-0.87 (-1.77, 0.04)] than HEU [0.81 (0.67, 0.94)] and unexposed [0.55 (0.33, 0.78)] infants. LVZ showed similar associations. In both periods, sick infants and those exposed to higher maternal viral loads had lower WVZ. Higher mean LVZ was associated with low birth weight. Infants that had received nevirapine had higher LVZ. In conclusion, HIV infection and not exposure was associated with low WVZ and LVZ in period 1. Eliminating infant HIV infection is a critical component in averting HIV-related poor growth patterns in infants in the first 6 mo of life.

Cost of childhood diarrhoea in rural South Africa: exploring cost-effectiveness of universal zinc supplementation.

OBJECTIVE: To describe the cost of diarrhoeal illness in children aged 6-24 months in a rural South African community and to determine the threshold prevalence of stunting at which universal Zn plus vitamin A supplementation (VAZ) would be more cost-effective than vitamin A alone (VA) in preventing diarrhoea. DESIGN: We conducted a cost analysis using primary and secondary data sources. Using simulations we examined incremental costs of VAZ relative to VA while varying stunting prevalence. SETTING: Data on efficacy and societal costs were largely from a South African trial. Secondary data were from local and international published sources. SUBJECTS: The trial included children aged 6-24 months. The secondary data sources were a South African health economics survey and the WHO-CHOICE (CHOosing Interventions that are Cost Effective) database. RESULTS: In the trial, stunted children supplemented with VAZ had 2·04 episodes (95 % CI 1·37, 3·05) of diarrhoea per child-year compared with 3·92 episodes (95 % CI 3·02, 5·09) in the VA arm. Average cost of illness was $Int 7·80 per episode (10th, 90th centile: $Int 0·28, $Int 15·63), assuming a minimum standard of care (oral rehydration and 14 d of therapeutic Zn). In simulation scenarios universal VAZ had low incremental costs or became cost-saving relative to VA when the prevalence of stunting was close to 20 %. Incremental cost-effectiveness ratios were sensitive to the cost of intervention and coverage levels. CONCLUSIONS: This simulation suggests that universal VAZ would be cost-effective at current levels of stunting in parts of South Africa. This requires further validation under actual programmatic conditions.

Ready-to-use food-allocation policy to reduce the effects of childhood undernutrition in developing countries.

Several aid groups have proposed strategies for allocating ready-to-use (therapeutic and supplementary) foods to children in developing countries. Analysis is needed to investigate whether there are better alternatives. We use a longitudinal dataset of 5,657 children from Bwamanda to construct a bivariate time-series model that tracks each child's height-for-age z score (HAZ) and weight-for-height z score (WHZ) throughout the first 5 y of life. Our optimization model chooses which individual children should receive ready-to-use therapeutic or supplementary food based on a child's sex, age, HAZ, and WHZ, to minimize the mean number of disability-adjusted life years (DALYs) per child during 6-60 mo of age [which includes childhood mortality calculated from a logistic regression and the lifelong effects of stunting (i.e., low HAZ)] subject to a budget constraint. Compared with the strategies proposed by the aid groups, which do not use HAZ information, the simple strategy arising from our analysis [which prioritizes children according to low values of a linear combination of HAZ, WHZ, and age and allocates the entire budget to therapeutic (i.e., 500 kcal/d) food for the prioritized children] reduces the number of DALYs by 9% (for the same budget) or alternatively incurs the same number of DALYs with a 61% reduction in cost. Whereas our qualitative conclusions appear to be robust, the quantitative results derived from our analysis should be treated with caution because of the lack of reliable data on the impact of supplementary food on HAZ and WHZ, the application of our model to a single cohort of children and the inclusion and exclusion errors related to imperfect food targeting.

Clinical and contextual determinants of anthropometric failure at baseline and longitudinal improvements after starting antiretroviral treatment among South African children.

OBJECTIVES: To describe baseline nutritional anthropometry and its determinants in a cohort of children commencing HAART, and subsequent longitudinal anthropometric trajectories over 2 years. METHODS: Prospective observational study in a prepubertal cohort of children commencing HAART in Durban, South Africa. RESULTS: Among 151 children with a median baseline age of 61.3 months (IQR 29.6, 90.1), prevalence of stunting was 54% (95% CI 46, 62) and of underweight, 37% (95% CI 29, 45). There was high prevalence of preceding respiratory and diarrhoeal comorbidities, which were associated with poorer anthropometry. There were significant improvements in height, weight and mid-upper-arm circumference z-scores after initiation of HAART regardless of preceding comorbidities. Stunted children remained shorter on average after 24 months, but younger children had better catch-up. Children who eventually died had persistently worse anthropometry. Children who were exposed to improved programs for prevention of mother-to-child transmission (PMTCT) were younger and had more severe growth impairments at baseline. CONCLUSION: Anthropometric status of children on HAART is influenced by age, preceding comorbidities, and by programmatic factors. With improved PMTCT programs, infants who would previously have died in infancy are now surviving to commence HAART. Poor outcomes are preceded by persistent anthropometric failure on HAART reaffirming the need for growth velocity monitoring.

Child mortality as predicted by nutritional status and recent weight velocity in children under two in rural Africa.

WHO has released prescriptive child growth standards for, among others, BMI-for-age (BMI-FA), mid-upper arm circumference-for-age, and weight velocity. The ability of these indices to predict child mortality remains understudied, although growth velocity prognostic value underlies current growth monitoring programs. The study aims were first to assess, in children under 2, the independent and combined ability of these indices and of stunting to predict all-cause mortality within 3 mo, and second, the comparative abilities of weight-for-length (WFL) and BMI-FA to predict short-term (<3 mo) mortality. We used anthropometry and survival data from 2402 children aged between 0 and 24 mo in a rural area of the Democratic Republic of Congo with high malnutrition and mortality rates and limited nutritional rehabilitation. Analyses used Cox proportional hazard models and receiver operating characteristic curves. Univariate analysis and age-adjusted analysis showed predictive ability of all indices. Multivariate analysis without age adjustment showed that only very low weight velocity [HR = 3.82 (95%CI = 1.91, 7.63); P < 0.001] was independently predictive. With age adjustment, very low weight velocity [HR = 3.61 (95%CI = 1.80, 7.25); P < 0.001] was again solely retained as an independent predictor. There was no evidence for a difference in predictive ability between WFL and BMI-FA. This paper shows the value of attained BMI-FA, a marker of wasting status, and recent weight velocity, a marker of the wasting process, in predicting child death using the WHO child growth standards. WFL and BMI-FA appear equivalent as predictors.

Target weight gain for moderately wasted children during supplementation interventions--a population-based approach.

OBJECTIVE: In malnourished populations, the weight-for-height Z-score (WHZ) distribution is shifted to the left. The aim of nutrition interventions should be to restore a normal WHZ distribution for the whole population. The present paper examines the WHZ change needed by each individual to achieve this objective. DESIGN: We developed a mathematical model of required individual change in WHZ as a function of characteristics of the initial population to restore a normal distribution. This model was then tested by simulating WHZ change needed to restore a normal WHZ distribution in a test population. SETTING: A rural area of Democratic Republic of the Congo with a high prevalence of undernutrition. SUBJECTS: Children under 5 years of age. RESULTS: To restore a normal distribution for the whole population, the WHZ of all children should be shifted. The desired WHZ change of each individual should be higher when the individual's initial WHZ is low, when the mean WHZ of the whole population is low and, for the most wasted individual, when the variance of WHZ and WHZ change in the population are high. Using the suggested model in a simulation on the test population resulted in a WHZ distribution close to the growth standard. CONCLUSIONS: To restore a normal WHZ distribution in wasted populations, nutritional programmes should cover the whole population with a higher weight gain in areas where mean WHZ is low.

Challenging the role of social norms regarding body weight as an explanation for weight, height, and BMI misreporting biases: development and application of a new approach to examining misreporting and misclassification bias in surveys.

BACKGROUND: Cultural pressures to be thin and tall are postulated to cause people to misreport their body weight and height towards more socially normative (i.e., desirable) values, but a paucity of direct evidence supports this idea. We developed a novel non-linear approach to examining weight, height, and BMI misreporting biases and used this approach to examine the association between socially non-normative weight and misreporting biases in adults. METHODS: The Survey of Lifestyles, Attitudes, and Nutrition 2007 (SLÁN 2007), a nationally representative survey of the Republic of Ireland (N = 1942 analyzed) was used. Self-reported weight (height) was classified as under-reported by ≥ 2.0 kg (2.0 cm), over-reported by ≥ 2.0 kg (2.0 cm), or accurately reported within 2.0 kg (2.0 cm) to account for technical errors of measurement and short-term fluctuations in measured weight (height). A simulation strategy was used to define self-report-based BMI as under-estimated by more than 1.40 kg/m2, over-estimated by more than 1.40 kg/m2, or accurately estimated within 1.40 kg/m2. Patterns of biases in self-reported weight, height, and BMI were explored. Logistic regression was used to identify factors associated with mis-estimated BMI and to calculate adjusted odds ratios (AOR) and 99% confidence intervals (99%CI). RESULTS: The patterns of bias contributing the most to BMI mis-estimation were consistently, in decreasing order of influence, (1) under-reported weight combined with over-reported height, (2) under-reported weight with accurately reported height, and (3) accurately reported weight with over-reported height. Average bias in self-report-based BMI was -1.34 kg/m2 overall and -0.49, -1.33, and -2.66 kg/m2 in normal, overweight, and obese categories, respectively. Despite the increasing degree of bias with progressively higher BMI categories, persons describing themselves as too heavy were, within any given BMI category, less likely to have under-estimated BMI (AOR 0.5, 99%CI: 0.3-0.8, P < 0.001), to be misclassified in a lower BMI category (AOR 0.3, 99%CI: 0.2-0.5, P < 0.001), to under-report weight (AOR 0.5, 99%CI: 0.3-0.7, P < 0.001), and to over-report height (OR 0.7, 99%CI: 0.6-1.0, P = 0.007). CONCLUSIONS: A novel non-linear approach to examining weight, height, and BMI misreporting biases was developed. Perceiving oneself as too heavy appears to reduce rather than exacerbate weight, height, and BMI misreporting biases.

Post-partum weight change patterns in the WHO Multicentre Growth Reference Study.

The interplay of factors that affect post-partum loss or retention of weight gained during pregnancy is not fully understood. The objective of this paper is to describe patterns of weight change in the six sites of the World Health Organization (WHO) Multicentre Growth Reference Study (MGRS) and explore variables that explain variation in weight change within and between sites. Mothers of 1743 breastfed children enrolled in the MGRS had weights measured at days 7, 14, 28 and 42 post-partum, monthly from 2 to 12 months and bimonthly thereafter until 24 months post-partum. Height, maternal age, parity and employment status were recorded and breastfeeding was monitored throughout the follow-up. Weight change patterns varied significantly among sites. Ghanaian and Omani mothers lost little or gained weight post-partum. In Brazil, India, Norway and USA, mothers on average lost weight during the first year followed by stabilization in the second year. Lactation intensity and duration explained little of the variation in weight change patterns. In most sites, obese mothers tended to lose less weight than normal-weight mothers. In Brazil and Oman, primiparous mothers lost about 1 kg more than multiparous mothers in the first 6 months. In India and Ghana, multiparous mothers lost about 0.6 kg more than primiparas in the second 6 months. Culturally defined mother-care practices probably play a role in weight change patterns among lactating women. This hypothesis should stimulate investigation into gestational weight gain and post-partum losses in different ethnocultural contexts.

Sociodemographic, lifestyle, mental health and dietary factors associated with direction of misreporting of energy intake.

OBJECTIVE: To estimate the extent of under- and over-reporting, to examine associations with misreporting and sociodemographic and lifestyle characteristics and mental health status and to identify differential reporting in micro- and macronutrient intake and quality of diet. DESIGN: A health and lifestyle questionnaire and a semi-quantitative FFQ were completed as part of the 2007 Survey of Lifestyle, Attitudes and Nutrition. Energy intake (EI) and intake of micro- and macronutrients were determined by applying locally adapted conversion software. A dietary score was constructed to identify healthier diets. Accuracy of reported EI was estimated using the Goldberg method. ANOVA, χ2 tests and logistic regression were used to examine associations. SETTING: Residential households in Ireland. SUBJECTS: A nationally representative sample of 7521 adults aged 18 years or older. RESULTS: Overall, 33·2 % of participants were under-reporters while 11·9 % were over-reporters. After adjustment, there was an increased odds of under-reporting among obese men (OR = 2·01, 95 % CI 1·46, 2·77) and women (OR = 1·68, 95 % CI 1·23, 2·30) compared to participants with a healthy BMI. Older age, low socio-economic status and overweight/obesity reduced the odds of over-reporting. Among under-reporters, the percentage of EI from fat was lower and overall diet was healthier compared to accurate and over-reporters. The reported usage of salt, fried food consumption and snacking varied significantly by levels of misreporting. CONCLUSIONS: Patterns in differential reporting were evident across sociodemographic, lifestyle and mental health factors and diet quality. Consideration should be given to how misreporting affects nutrient analysis to ensure sound nutritional policy.