the nutritional status of - Health Systems Trust

A direct comparison of the results from the SALDRU/World Bank and the 1994 National Survey (SAVACG, 1995; Table
8) with the compilation (calculated means) of the smaller studies done from 1976 to 1996 is not possible. Changing
circumstances over 20 years such as droughts, economic recession, improved health services, changed political
structures, as well as an absence of proper randomisation or selection bias in the smaller studies, could be
responsible for observed differences. However, looking at calculated means, the same overall pattern of low prevalence
of underweight, moderate to high prevalences of stunting in the absence of wasting, emerged. The wide range of
percentages of children under a specific cutpoint for all three indices (W-a, H-a and W-H) as summarised in Table
8 further emphasises that there are areas with high prevalences of malnutrition.
3.1.5 PRIMARY SCHOOL CHILDREN
Tables 9 to 14 give information on the anthropometric indices of primary school children, as well as percentages of
children under the 3rd or 5th percentile of these indices. Most children were between 6 and 12 years old, but some
studies included slightly older children. The data were collected from 1975 to 1996 and 34 374 children were
weighed and measured. For this analysis, the children were divided into 111 subgroups based on age, gender,
ethnicity and geographical area. The data include 20 000 children aged 6 to 9 years who were measured in the
1980 National Survey (Kotzé et al., 1982). Without this group, the anthropometry of only 14 374 primary school
children were studied by individual researchers over a period of 20 years. However, Table 15 gives data on the 1994
National Survey (Department of Health, 1994). This study included 97 790 children or 4.9 % of all school entrants
in the Republic of South Africa. These children were randomly selected from 3 300 schools using 10 schools per
magisterial district in the four Education Departments (Houses of Assembly, Representatives, Delegates and Education
and Training) of the previous Government to represent children from all four population groups. For the purpose of
this analysis, the assumption was made that these would represent the white, coloured, Indian and black children
respectively.
Table 16 summarises some of the data contained in Tables 9-15. For comparison, the mean figures obtained in the
1994 National Survey for each ethnic group are also given in this table. The mean percentages were calculated
from all studies except the 1994 National Survey. No corrections for the number or distribution of subjects in the
smaller studies were done. The data should therefore be interpreted with care. Nevertheless, the prevalences of
underweight and stunting in all population groups seemed to be higher in the smaller studies than in the 1994
National Survey. Both sets of data indicate that wasting (low W-H) is not a serious problem on a national basis,
although the wide range in prevalence reported in different studies, indicates that it is a serious problem in several
areas and in particular groups of children.
One reason for the differences in prevalences of underweight and stunting is probably that in the smaller studies
some groups of children were examined because it was suspected that they were malnourished, leading to selection
bias. For example, the Indian children studied by Van Rensburg et al. (1977) were from a socio-economically
deprived area in Durban and they were selected on a basis of scoring during aptitude tests. This study showed that
the majority of children were growth retarded and that they could be classified as “slow learners”. These authors
remarked that despite the low weights and heights of the Indian children, their skinfold thickness was close to
normal, as judged by conventional standards. The normal or “thicker” skinfolds of Indian children were also
observed in other studies (Kotzé et al., 1986; Vorster et al., 1994).
Comparing weights and heights and weight and height increases in the 6, 7, 8 and 9 year old children of the 1980
National Survey, Kotzé et al. (1982) observed that white children had the highest growth rate. Indian boys initially
had the lowest weight, and put on weight later than the coloured and black boys. But they grew faster in height
than the boys of the other two ethnic groups. Black children weighed more than the Indian and coloured children
but they had the slowest growth rate (in weight and height) over this age period.
In Table 17, the prevalences of stunting (low H-a) obtained in the three recent National Surveys on preschool
(SALDRU/World Bank 1993/1994; SAVACG 1995) and primary school children (Department of Health, 1994) are given.
On a national level, the percentages of stunted preschool children were 25.4 and 22.9, while the percentage of
stunted school entrants was 13.2. This 10 % difference is difficult to explain. It is possible that undernourished
children are kept at home and sent to school later, but both studies on preschool children had an age cutpoint (60
and 72 months). All three studies were randomised and included children from the previous Homelands. However,
differences in the provinces that did not have Homelands, such as the Western Cape, Northern Cape and Gauteng,
were smaller than the provinces that included the Transkei (Eastern Cape), Bophutatswana (Free State and North
West Province) and Venda (Northern Province). Therefore, it seems that insufficient randomisation of subjects could
be a possible reason. The prevalences of stunting obtained in the SALDRU/World Bank study for the different
provinces are generally higher than those of the SAVACG study. Due to measurement error, the body weights of
children in the SALDRU/World Bank study could not be used (Harrison, 1995). The possibility that heights and ages
were not accurate cannot, therefore, be ruled out.
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