Trachoma grading: observer trials conducted in southern Malawi

ABSTRACT

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: