This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
[{'content': 'ECG was performed on a total of 700 subjects with complaints of acute chest pain. Of these, 520 patients had myocardial infarction. Calculate the positive predictive value of ECG is:\\r\\n\\r\\n \\r\\n\\r\\n\\r\\n\\r\\nMYOCARDIAL INFARCTION\\r\\n\\r\\n \\r\\n \\r\\n \\r\\n\\r\\n\\r\\n\\r\\nECG\\r\\n\\r\\n\\r\\nPRESENT\\r\\n\\r\\n\\r\\nABSENT\\r\\n\\r\\n\\r\\nTOTAL\\r\\n\\r\\n\\r\\n\\r\\n\\r\\nPOSITIVE\\r\\n\\r\\n\\r\\n416\\r\\n\\r\\n\\r\\n9\\r\\n\\r\\n\\r\\n425\\r\\n\\r\\n\\r\\n\\r\\n\\r\\nNEGATIVE\\r\\n\\r\\n\\r\\n104\\r\\n\\r\\n\\r\\n171\\r\\n\\r\\n\\r\\n275\\r\\n\\r\\n\\r\\n\\r\\n\\r\\nTOTAL\\r\\n\\r\\n\\r\\n520\\r\\n\\r\\n\\r\\n180\\r\\n\\r\\n\\r\\n700\\r\\n\\r\\n\\r\\n\\r\\n\\r\\n\\r\\n \nSelect and explain. \nA. 40%, B. 55%, C. 95%, D. 98%', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Positive predictive value=true positive/(true positive+ false positive) 416/425 x 100= 98% Ref: Medical biostatistics, 1st edition pg: 201', 'role': 'assistant'}]