A comparison of the National Center for Health Statistics and new World Health Organization growth references for school-age children and adolescents with the use of data from 11 low-income countries.

BACKGROUND: In 2007 new World Health Organization (WHO) growth references for children aged 5-19 y were introduced to replace the National Center for Health Statistics (NCHS) references. OBJECTIVE: This study aimed to compare the prevalence of stunting, wasting, and thinness estimated by the NCHS and WHO growth references. DESIGN: NCHS and WHO height-for-age z scores were calculated with the use of cross-sectional data from 20,605 schoolchildren aged 5-17 y in 11 low-income countries. The differences in the percentage of stunted children were estimated for each year of age and sex. The z scores of body mass index-for-age and weight-for-height were calculated with the use of the WHO and NCHS references, respectively, to compare differences in the prevalence of thinness and wasting. RESULTS: No systematic differences in mean z scores of height-for-age were observed between the WHO and NCHS growth references. However, z scores of height-for-age varied by sex and age, particularly during early adolescence. In children for whom weight-for-height could be calculated, the estimated prevalence of thinness (WHO reference) was consistently higher than the prevalence of wasting (NCHS reference) by as much as 9% in girls and 18% in boys. CONCLUSIONS: In undernourished populations, the application of the WHO (2007) references may result in differences in the prevalence of stunting for each sex compared with results shown when the NCHS references are used as well as a higher estimated prevalence of thinness than of wasting. An awareness of these differences is important for comparative studies or the evaluation of programs. For school-age children and adolescents across all ranges of anthropometric status, the same growth references should be applied when such studies are undertaken.

Determinants of high vitamin A supplementation coverage among pre-school children in Mali: the National Nutrition Weeks experience.

OBJECTIVES: To assess vitamin A supplementation (VAS) coverage of children aged 6-59 months and the factors that favour or limit this coverage during the National Nutrition Weeks in Mali. DESIGN: Cross-sectional study. Interviews about demographic factors and children's adherence to the vitamin A capsule distribution programme were conducted. Professionals' knowledge of vitamin A and various aspects related to the supplementation strategy were assessed. SETTING: Five regions out of the eight regions in the country, in addition to Bamako District. Three rural communes were selected in three regions to represent rural areas. SUBJECTS: Parents or caregivers of children under 5 years of age, health agents who participated in the weeks, and community and administrative leaders. RESULTS: At least 80% of the children received the supplement. More 'traditional' communication channels (town criers, friends and family members) appeared to be more effective in reaching the target groups than modern methods, i.e. radio and television. Mothers' possession of a radio (Pearson chi2 = 5.03; P = 0.025) and fathers' education (Pearson chi2 = 19.02; P < 0.001), possession of a radio (Pearson chi2 = 8.93; P = 0.003) and listening to it (Pearson chi2 = 7.62; P = 0.006) all appeared to be statistically and significantly associated with children's coverage. In multivariate logistic regression analysis, only the study site (urban/rural) (P = 0.004), 'traditional channels' (P = 0.02) and fathers' education (P = 0.04) were significantly associated with children's coverage. Knowledge about VAS was high among community and administrative leaders, and health professionals. The planning and implementation of activities at the district level were found to be good in general. CONCLUSION: National Nutrition Weeks provide a successful example of a periodic VAS strategy with high coverage among children aged 6-59 months in Mali. Campaigns aimed at informing and sensitising populations during the Nutrition Weeks should also target children's fathers.

Validation of the second version of a quantitative food-frequency questionnaire for use in Western Mali.

OBJECTIVE: To assess the relative validity of the second version of a quantitative food-frequency questionnaire (QFFQ), designed to measure the habitual food and nutrient intake in one season in rural populations in Western Mali, West Africa. DESIGN: The dietary intake during the previous week was assessed with the 164-item QFFQ administered by interview. This was compared with the intake from a 2-day weighed record (WR) with weighed recipes. SETTING: The village of Ouassala in the Kayes region, Western Mali. SUBJECTS: Thirty-four women and 36 men aged 15-45 years, from 29 households. RESULTS: The QFFQ gave a lower intake of lunch and dinner and a higher intake of snacks than the WR. The discrepancies were larger for women than for men. The median proportion of subjects classified in the same quartile of intake was 29% for food groups and 36% for energy and nutrients. For classification into extreme opposite quartiles, the median proportion was 6% for food groups and 7% for energy and nutrients. Spearman's rank correlation for energy and nutrients ranged from 0.16 (% energy from protein) to 0.62 (retinol equivalents). CONCLUSIONS: The second version of the QFFQ tends to underestimate total food weight. The methods used for estimating food portion size should therefore be applied with caution. The changes made from the first version had little effect. The ability to rank subjects according to dietary intake is similar with both versions. The improved layout of the new QFFQ makes it a more user-friendly tool for comparing dietary intake between population groups and for measuring changes over time.

A randomised trial in Mali of the effectiveness of weekly iron supplements given by teachers on the haemoglobin concentrations of schoolchildren.

OBJECTIVE: To assess the effect on the haemoglobin concentrations of schoolchildren of weekly iron tablets administered by teachers. DESIGN: Sixty schools were randomly assigned to two groups: in 30 schools children were given weekly for 10 weeks a tablet providing 65 mg of iron and 0.25 mg of folic acid; in the other 30 schools no iron tablets were given. All children were dewormed and given vitamin A before the study began. The haemoglobin concentration of up to 20 randomly selected children in each school was estimated before and 2 weeks after the end of treatment. SETTING: Rural community schools in Kolondieba district of Mali. SUBJECTS: Some 1113 schoolchildren aged 6-19 years with a mean of 11.4 years. RESULTS: The haemoglobin concentration of treated children rose on average by 1.8 g l(-1) and the prevalence of anaemia fell by 8.2%; in untreated children the haemoglobin concentration fell by an average of -2.7 g l(-1) and the prevalence of anaemia rose by 9.4%. The fall in haemoglobin concentration among untreated girls of -4.0 g l(-1) was greater than in untreated boys (-0.3 g l(-1) ). CONCLUSIONS: Weekly iron tablets given by teachers prevented a general fall in the haemoglobin concentrations of untreated children, and led to a small but statistically significant rise among treated children. Young children benefited more than children aged >or=12 years, and girls benefited more than boys.