Which of the following is least likely to be a threat to validity in a single-group before-after design?

Question

Quizplus · Accepted Answer

Selection is least likely to be a threat in a single-group before-after design because there is no comparison group from which participants are selected differently. This design involves observing the same group of participants before and after an intervention, so selection bias related to forming comparison groups does not apply.

Which of the Following Is Least Likely to Be a Threat