Identifying areas with vitamin A deficiency: the validity of a semiquantitative food frequency method.
OBJECTIVE
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%).
Sloan
N L
NL
Population Council, New York, NY 10017, USA.
Rosen
D
D
de la Paz
T
T
Arita
M
M
Temalilwa
C
C
Solomons
N W
NW
D002675:Child, Preschool; D004034:Diet Surveys; D005069:Evaluation Studies as Topic; D005260:Female; D006166:Guatemala / Q000453:epidemiology; D006801:Humans; D007223:Infant; D008297:Male; D009752:Nutritional Status; D010679:Philippines / Q000453:epidemiology; D015203:Reproducibility of Results; D013636:Tanzania / Q000453:epidemiology; D014801:Vitamin A / Q000008:administration & dosage / Q000097:blood; D014802:Vitamin A Deficiency / Q000453:epidemiology*
D014801:Vitamin A