Ans. is 'a' i.e., Prevalence is 5%; 'b' i.e., Sensitivity is 70% & 'c' i.e., Specificity is 80% In this question : Total patients = 500 (diabetic patients) True positive patients = 350 Thus remaining 150 (500-350) are false negative. 350 So, sensitivity of test = 350+150 70% Similarly, Total non-diseased are = 9500 (10000-500) Among these false positive are = 1900 Thus remaining 7600 are ture negative (9500-1900) 7600 So, specificity of test = = 80% 9500 500 o Prevalance of disease = x 100 = 5% 10000