Which of the following threats to internal validity CANNOT occur in just any study?
A)Observer bias
B)History threats
C)Placebo effects
D)Demand characteristics

Question

Quizplus · Accepted Answer

History threats are specific to studies that involve interventions that occur over an extended period of time, such as a treatment program, and cannot occur in studies that do not involve such interventions. Observer bias, placebo effects, and demand characteristics can occur in any study.

Which of the Following Threats to Internal Validity CANNOT Occur