Random assignment of subjects to experimental and control groups has which of these effects?
A) Minimizes mortality within groups
B) Maximizes variance between groups
C) Decreases systematic bias
D) Increases selection bias

Question

Quizplus · Accepted Answer

Random assignment of subjects to experimental and control groups ensures that any systematic differences between the groups are distributed randomly. This reduces the likelihood of systematic bias, which is a potential source of error in experiments. Random assignment helps to ensure that any observed differences between the groups are due to the intervention being tested rather than preexisting differences between the groups. Random assignment does not necessarily minimize mortality within groups, maximize variance between groups, or increase selection bias.

Random Assignment of Subjects to Experimental and Control Groups Has