This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Statistical Errors, p-value, Subject name: Social & Preventive Medicine
[{'content': 'All are true about P-value except: \nSelect and explain. \nA. Is the probability of committing Type -I error, B. Is equal to 1-beta, C. Is the chance that the presence of difference is concluded when actually there is none, D. When P- value is less than a, the result is statistically significant', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Type I error is usually fixed in advance by the choice of level of significant employed in the test Type I error is more serious than Type II error Power of a test: 1-b -Is probability of rejecting a Null hypothesis when a predetermined clinically significant difference is indeed present -Power can be increased by increasing the no. of subjects in a trial There is no mathematical relationship between a and b.', 'role': 'assistant'}]