Which of the following is a threat to internal validity?
A) failing to use a representative sample of subjects
B) misinterpreting subject's behavior
C) failing to debrief subjects
D) failing to make the treatment and no-treatment groups equivalent prior to the introduction of the treatment

Question

Quizplus · Accepted Answer

Failing to make the treatment and no-treatment groups equivalent prior to the introduction of the treatment is a threat to internal validity because it can lead to confounding variables affecting the outcome, making it unclear if the treatment itself caused any observed effects.

Which of the Following Is a Threat to Internal Validity