This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Definition and Concepts, Examples from NHPs, Subject name: Social & Preventive Medicine
[{'content': 'Diagnostic power of the test is reflected by: \nSelect and explain. \nA. Sensitivity, B. Specificity, C. Predictive value, D. Population attributable risk', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Diagnostic power of a screening test: Predictive accuracy (it tells the actual no. of people having the disease or not having the disease out of those shown positive or negative by a screening test) Diagnostic power of a screening test to correctly identify disease: positive predictive value (PPV) Diagnostic power of a screening test to correctly exclude a disease: negative predictive value (NPV)', 'role': 'assistant'}]