ABSTRACT
Se han creado pruebas sencillas pero útiles para el tamizaje de personas con visión disminuida en países en desarrollo. Estas pruebas, que miden la visión de lejos y de cerca y que se basan en el uso de una figura en E, fueron evaluadas y respaldadas mediante ensayos en que participaron personas de 4 a 90 años de edad, y se han puesto a prueba en los servicios de salud, educación y rehabilitación de 32 países en desarrollo. Se han calculado su sensibilidad y especificidad como instrumentos para la detección de la visión disminuída: en la prueba de visión a distancia, la sensibilidad es de 85 por ciento y la especificidad, de 96 por ciento; en la prueba de visión cercana, la sensibilidad es de 100 por ciento y la especificidad, de 84 por ciento. Se ha demostrado que el contenido y el formato de las pruebas son adecuados para países en desarrollo y se ha comprobado la utilidad de las mismas para el tamizaje de la visión disminuida
Subject(s)
Case-Control Studies , Mass Screening , Vision, Low , Developing CountriesABSTRACT
A population-based prevalence survey of ocular disease was conducted in the Lower Shire Valley of Malawi in 1983. A total of 5;436 children less than 6 years of age and 1;664 persons greater than or equal to 6 years were examined. The prevalence of inflammatory trachoma peaked in the 1-2-year-old age group at 48.7 percent and declined rapidly with age to less than 5 percent by age 15. The prevalence of cicatricial trachoma was low in young children and climbed gradually with age to greater than 40 percent among those greater than or equal to 50 years. Risk factors for infLammatory disease in young children included low socioeconomic status of the family; long walking distance to the household's primary source of water; absence of a latrine in the family compound; and presence of trachoma among siblings. Indices of crowding practices were not associated with inflammatory disease. An apparent inverse association of facewashing and inflammatory trachoma in children did not hold up when adjusted for other risk factors
Subject(s)
Socioeconomic FactorsABSTRACT
A variety of grading schemes have been proposed for the clinical classification of inflammatory trachoma. During a population based study of ocular disease conducted in southern Malawi we tested a simplified version of the current WHO grading scheme. Intraobserver agreement statistics were less than satisfactory for three of four graders. Interobserver agreement when compared against either a well experienced standard ophthalmologist or a consensus grade improved over time for two of the three graders. However; initial agreement for all three graders was only fair to moderate. Previous studies of trachoma grading schemes support these unsatisfactory results. A new system of classification is needed that is both accurate and reliable in a field setting