This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Biostats, Subject name: Social & Preventive Medicine
[{'content': 'A randomized trial comparing the efficacy of two drugs showed a difference between the two (p<0.05). Assume that in reality, however, the two drugs to not differ. This is therefore an example of:- \nSelect and explain. \nA. Type I error, B. Type II error, C. 1 - alpha, D. 1 - beta', 'role': 'user'}, {'content': "Answer: A \nExplanation: STATISTICAL ERRORS & P - VALUE H0 rejected H0 not rejected Null hypothesis (H0) true Null hypothesis (H0) false Type I error No error No error Type II error Type I error: Null hypothesis is true but rejected. Probability of type I error is given by 'P value'. (probability of declaring a significant difference when actually it is not present) Significance (alpha) level: is the maximum tolerable probability of type I error. Alpha is fixed in advance: p - value calculated can be less than, equal to or greater than alpha. Keep type I error to be minimum (P<alpha); Then results are declared statistically significant. Type II error: Null hypothesis is false but not rejected. (or accepted) Probability of Type II error is given by beta. (probability of declaring no significant difference when actually it is present) Type I error is more serious than type II error.", 'role': 'assistant'}]