Development of screening indicators for ranking areas at risk of vitamin A deficiency in Thailand.

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 of 3 provinces who were previously identified to have various degrees of vitamin A deficiency were randomly selected to participate in the study. These villages were located in Songkhla, Yala and Narathiwat provinces. Data collection included anthropometric measurements, serum retinol analysis, data on dietary intake, illness, and socioeconomic status. Subsamples of 120 children were taken for Modified Relative Dose Response. 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 at > or = 15 per cent of children with serum retinol < 0.70 micromol/l. Findings revealed that the screening indicators could identify areas at risk of vitamin A deficiency with 83.3 per cent 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.

Optimized nuclear techniques and thyroid function studies in the newborn in iodine-deficient areas of Thailand.

Cord blood samples, as sera (n=4,753) and dried blood spots (n=855) obtained from subjects in iodinedeficient districts in northern Thailand, were studied for T4 and TSH. The methodology was optimized by the used of NETRIA bilk reagents and in-house methods were developed to adapt them for cost reduction, convenience and precision/accuracy. The biochemical findings with cut-off values at < 3 µg/dl for T4 and >50 mIU/L for TSH as confirmed by <1ng/dl for FT47 showed 16 cases (0.34%) of neonatal chemical hypothyroidism (NCH) varying from 0.18 to 1.59 percent of 4,753 cases. Out of the total 4,753 cases, 1.45 percent (n=96) could benefit from thyroxine administration. In this research project, the screening indicated a mild to moderate degree of IDD severity. The findings are useful for epidemiological monitoring and for advocacy of the IDD prevention and control programme.