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Listening practice
/ Section PM25
Listen to an Academic Talk
Listen to part of a talk in a medical statistics class.
Listen
46. Why does the speaker mention a third arm?
A
To describe the design needed to isolate the effect of belief
B
To explain why placebo trials are expensive to run
C
To argue that two-arm trials produce unreliable drug results
D
To show how patients are allocated to groups at random