<prompt> Formula for calculating positive predictive value PPV:aabdcdaacdbd  <response>: Ans: a aabRef: Park, 24th edition, Page 149Basic measures used in evaluation of a diagnostic test are:a. Sensitivity and specificityb. Predictive values - positive predictive value and negative predictive valueSensitivityAbility of the test to identify true positivesSpecificityAbility of the test to identify true negativesPositive predictive valueProbability that a patient with positive test result truly has the diseaseNegative predictive valueProbability that a patient with negative test result truly does not have the disease Screening testDia 