Abstract
Abstract: :
Purpose:To evaluate the reliability and validity of the Bedside Retinal Exam in detecting and grading Age–Related Macular Degeneration (AMD). Methods:In a prospective reliability and validity study, patients over fifty years of age were examined with the Bedside Retinal Exam that consisted of only direct ophthalmoscopy and indirect ophthalmoscopy with a 20–diopter lens. All 56 patients were examined by both one trained and untrained investigator. Both investigators, a retina specialist and a senior ophthalmology resident, were masked to all clinical data. Patients were first graded as to whether AMD was present. Those deemed to have AMD were then graded according to the Clinical Age–Related Maculopathy Classification System (Table 1). Clinical fundus photos were taken on all patients and subsequently graded one month later by the retina specialist in a masked fashion. The reliability of this bedside technique was determined by measuring the interobserver agreement between the two investigators. Intraclass correlation was then measured to determine agreement with the gold standard of grading clinical fundus photos.The validity of this examination technique as a diagnostic test in detecting AMD was measured by determining the sensitivity, specificity and Odds Ratio. Results:The interobserver agreement of the Bedside Retinal Exam in detecting and grading AMD was very good with a kappa of 0.964 (p<0.05) and weighted kappa of 0.943 (p<0.05) respectively. The overall agreement of this technique to the gold standard of grading photographs was also strong with a weighted Alpha 0.978 (p<0.05).This technique also proved to be a good diagnostic tool with a sensitivity of 0.963 (95% CI, 0.845–0.998), specificity of 0.913 (95% CI, 0.774–0.954) and an Odds Ratio of 273.0 (95% CI, 18.7–10,288.5). Conclusions: The Bedside Retinal Exam is a technique that is reproducible in detecting and grading AMD changes. It is also a valid diagnostic tool in the detection and grading of AMD compared to gold standard of examing clinical photos. Therefore, the bedside exam may be a feasible alternative if biomicroscopic slit–lamp examination or fundus photography is not physically possible. Clinical Age–Related Maculopathy Classification System (Table 1)
Keywords: age–related macular degeneration • detection • macula/fovea