Kandavasee Maleevong. Development of screening indicators for ranking areas at risk of vitamin A deficiency in Thailand . Doctoral Degree(Public Health). Mahidol University. : Mahidol University, 2003.
Development of screening indicators for ranking areas at risk of vitamin A deficiency in Thailand
Abstract:
The objective of this study was to develop community based screening
indicators for identifying areas at risk of vitamin A deficiency. Three hundred
children aged 24-71 months in 12 villages were randomly selected to participate in the
study. These villages were located in Songkhla, Yala and Narathiwat provinces, and
these areas were known to have various degrees of evidence of vitamin A deficiency.
Anthropometric measurements and serum retinol analysis were conducted. Data on
dietary intake, illness, and socioeconomic status were obtained by interview with
mothers. Subsamples of 120 and 97 children were taken for Modified Relative Dose
Response and fecal examination for helminthic infections respectively. Statistics used
for data analysis were factor analysis, discriminant analysis and Receiver Operating
Characteristic curves. Sensitivity and specificity of the screening indicators were
calculated and compared with the rate of vitamin A deficiency classified by ≥ 15% of
children with serum retinol < 0.70 μmol/l.
Results revealed that the screening indicators could identify areas at risk of
vitamin A deficiency with 83.3% efficiency. Data to be used for identifying areas at
risk of vitamin A deficiency included home and land ownership for agriculture, dietary
intake of vitamin A, access to social services (maternal education and antenatal care),
vaccination, infectious diseases (diarrhoea and upper respiratory tract infection with
fever) and nutritional status.