Which statement best describes quasi-experiments in comparison to true experiments?

Which statement best describes quasi-experiments in comparison to true experiments?

• A. They examine cause-and-effect relationships without random assignment.
• B. They always use random assignment.
• C. They do not involve any control groups.
• D. They disregard independent variables.

Answer: (A)

Quasi-experiments pursue cause-and-effect questions but don’t use random assignment to put participants into groups. Instead, they rely on pre-existing groups or a natural event that creates a comparison, which means the groups may differ in ways other than the treatment. This is why they can suggest causal relationships, but the evidence isn’t as airtight as in true experiments where randomization helps balance those differences. Rigorous quasi-experimental designs (like nonequivalent groups, interrupted time series, or regression discontinuity when applicable) try to strengthen causal inferences, but they still hinge on the lack of random assignment. The other statements miss this key point: true experiments rely on random assignment; quasi-experiments may have comparison groups but not randomized ones; and independent variables are still studied, just without randomization.

Quasi-experiments pursue cause-and-effect questions but don’t use random assignment to put participants into groups. Instead, they rely on pre-existing groups or a natural event that creates a comparison, which means the groups may differ in ways other than the treatment. This is why they can suggest causal relationships, but the evidence isn’t as airtight as in true experiments where randomization helps balance those differences. Rigorous quasi-experimental designs (like nonequivalent groups, interrupted time series, or regression discontinuity when applicable) try to strengthen causal inferences, but they still hinge on the lack of random assignment. The other statements miss this key point: true experiments rely on random assignment; quasi-experiments may have comparison groups but not randomized ones; and independent variables are still studied, just without randomization.