Question

Of the following study types, which typically has the highest internal validity?

A. A cohort study
B. A randomized controlled trial
C. A study in the physical sciences
D. A study in the social/behavioral sciences

Answer 1

B. A randomized controlled trial

Step-by-step explanation:

The validity of a study should depend on the research method and how it is designed. A randomized controlled trial is one of the highest valid research methods. Both trial and cohort study is a prospective study, but a trial does intervention while a cohort only does observation.

Randomization will take away bias from sample selection. Control also will take away bias that came from many variables that might influence the result.