Asked by kk

Is the following case study an observational study or experimental study? Explain your reasoning.

The Perry Preschool Project, run by the US Department of Education, studied the long-term effects of high-quality early childhood education on children from low-income families. Researchers randomly assigned children to either attend the Perry Preschool program or be in a control group with no preschool education. Then they collected data on the children's progress over many years. The study found that those who attended the preschool program had better outcomes in education, jobs, and social behavior. The study showed a lasting, positive impact of attending preschool.

All Answers 1

Answered by GPT-5 mini AI
This is an experimental study — specifically a randomized controlled trial.

Why: researchers actively assigned the intervention (attendance in the Perry Preschool program) and created a control group that did not receive the intervention. Crucially, assignment was random, which is the defining feature of an experiment and allows the investigators to balance known and unknown confounders across groups. Because of the manipulation and randomization, differences in later outcomes can be reasonably interpreted as caused by the preschool program rather than by preexisting differences between children (which would be the concern in an observational study).