Search

espanolObjetivo: Analisis de la variabilidad interobservador de la biomicroscopia utilizada para el diagnostico de retinopatia diabetica. Metodos: Diseno: Observacional descriptivo. Valoracion en paralelo, de forma ciega para los observadores, del grado de retinopatia diabetica mediante biomicroscopia en pacientes diabeticos tipo 2. Muestra: Para la evaluacion del indice Kappa, con una estimacion de una proporcion de desacuerdo del 15%, (precision del 5% intervalo de confianza del 95%) muestra n=196, (siendo «n» el numero de ojos). Variables a medir: grado de retinopatia diabetica, segun la clasificacion del ETDRS modificada. Resultados: La edad media de los pacientes fotografiados fue de 65,42 anos (DE= 9,91). De las 217 biomicroscopias realizadas, en 191 se encontro concordancia total. En 24 la discordancia fue tan solo en un grado de la clasificacion del ETDRS y en 2 la discordancia fue en dos grados. En ningun caso fue mayor. Kappa ponderado cuadratico = 0,876, IC95%: 0,655-0,952 y Kappa ponderado lineal = 0,804, IC95%: 0,729-0,878. Conclusiones: El indice Kappa ponderado demuestra un grado de acuerdo «muy bueno». Las discrepancias producidas ademas de escasas no tienen trascendencia clinica, ya que no afectan a la decision de tratamiento. La biomicroscopia leida por un solo oftalmologo es un instrumento fiable como patron de referencia para el diagnostico de la retinopatia diabetica. EnglishObjective: Analysis of the inter-observer variability of biomicroscopy used for the diagnosis of Diabetic Retinopathy. Methods: This was a descriptive study. Parallel observer-blind evaluations of the degree of retinopathy in type 2 diabetic patients, as defined on biomicroscopic photographs, were performed by two ophthalmologists. The sample size required for the Kappa index among ophthalmologists with a disagreement ratio of 15%, precision ratio of 5% and confidence level of 95% is n=196 («n» being the number of eyes). The only variable measured was the degree of Diabetic Retinopathy, according to the modified Early Treatment Diabetic Research Study (ETDRS) classification. Results: The average age of the 217 patients photographed was of 65.42 years (SE= 9.91). In 191 instances there was total agreement between the 2 ophthalmologists. In 24 instances the discrepancy was only of one degree of the classification of the ETDRS, and in 2 the discrepancy was of two degrees. In no case was it greater than this. (Quadratic weighed Kappa = 0.876, IC95%: 0.655-0.952 and linear weighed Kappa = 0.804, IC95%: 0.729-0.878). Conclusions: The Weighed Kappa index demonstrated a «very good» agreement of the degree of diabetic retinopathy. The discrepancies were slight, were of no clinical importance, and would not have affected treatment decisions. The results indicate that this examination, performed by a single ophthalmologist, can be utilised as a reference standard in Diabetic Retinopathy diagnosis.