OBJECTIVES: The prevalence of vitamin A deficiency has traditionally been assessed through xerophthalmia or biochemical surveys. The cost and complexity of implementing these methods limits the ability of nonresearch organizations to identify vitamin A deficiency. This study examined the validity of a simple, inexpensive food frequency method to identify areas with a high prevalence of vitamin A deficiency. METHODS: The validity of the method was tested in 15 communities, 5 each from the Philippines, Guatemala, and Tanzania. Serum retinol concentrations of less than 20 micrograms/dL defined vitamin A deficiency. RESULTS: Weighted measures of vitamin A intake six or fewer times per week and unweighted measures of consumption of animal sources of vitamin A four or fewer times per week correctly classified seven of eight communities as having a high prevalence of vitamin A deficiency (i.e., 15% or more preschool-aged children in the community had the deficiency) (sensitivity = 87.5%) and four of seven communities as having a low prevalence (specificity = 57.1%). CONCLUSIONS: This method correctly classified the vitamin A deficiency status of 73.3% of the communities but demonstrated a high false-positive rate (42.9%).
OBJECTIVES: The prevalence of vitamin A deficiency has traditionally been assessed through xerophthalmia or biochemical surveys. The cost and complexity of implementing these methods limits the ability of nonresearch organizations to identify vitamin A deficiency. This study examined the validity of a simple, inexpensive food frequency method to identify areas with a high prevalence of vitamin A deficiency. METHODS: The validity of the method was tested in 15 communities, 5 each from the Philippines, Guatemala, and Tanzania. Serum retinol concentrations of less than 20 micrograms/dL defined vitamin A deficiency. RESULTS: Weighted measures of vitamin A intake six or fewer times per week and unweighted measures of consumption of animal sources of vitamin A four or fewer times per week correctly classified seven of eight communities as having a high prevalence of vitamin A deficiency (i.e., 15% or more preschool-aged children in the community had the deficiency) (sensitivity = 87.5%) and four of seven communities as having a low prevalence (specificity = 57.1%). CONCLUSIONS: This method correctly classified the vitamin A deficiency status of 73.3% of the communities but demonstrated a high false-positive rate (42.9%).
Authors: K P West; R P Pokhrel; J Katz; S C LeClerq; S K Khatry; S R Shrestha; E K Pradhan; J M Tielsch; M R Pandey; A Sommer Journal: Lancet Date: 1991-07-13 Impact factor: 79.321
Authors: G H Beaton; J Milner; P Corey; V McGuire; M Cousins; E Stewart; M de Ramos; D Hewitt; P V Grambsch; N Kassim; J A Little Journal: Am J Clin Nutr Date: 1979-12 Impact factor: 7.045
Authors: L Rahmathullah; B A Underwood; R D Thulasiraj; R C Milton; K Ramaswamy; R Rahmathullah; G Babu Journal: N Engl J Med Date: 1990-10-04 Impact factor: 91.245