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: MYOCARDIAL INFARCTION ECG PRESENT ABSENT TOTAL POSITIVE 416 9 425 NEGATIVE 104 171 275 TOTAL 520 180 700 \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'}]