When individuals' performance on a posttest differs from their initial testing not because of a treatment but because of familiarity with the measure,a __________ threat to internal validity is likely.
A)regression
B)instrumentation
C)testing
D)contamination

Question

Quizplus · Accepted Answer

The testing threat to internal validity occurs when individuals' performance on a posttest is influenced by their familiarity with the measure due to initial testing. This is not caused by the treatment itself, but rather by the experience of taking the measure at two different points in time. Regression refers to the phenomenon where individuals' extreme scores on a pretest regress towards the mean on a posttest, and is not relevant in this scenario. Instrumentation refers to changes in the measurement instrument or procedures over time, which could also impact posttest scores but is not mentioned as a factor in the scenario. Contamination refers to the spread of treatment effects from the treatment group to the control group, which also does not apply here.

When Individuals' Performance on a Posttest Differs from Their Initial