What are the benefits of a quasi-experimental design?

• A. When it is not ethical to manipulate the independent variable; Naturalistic — increases external validity
• B. It is randomized and controlled
• C. It has high internal validity
• D. It always has low external validity

Answer: (A)

Quasi-experimental designs are used when you can’t randomly assign participants or manipulate the independent variable because it would be unethical or impractical. In these designs you study real-world groups or events, often in natural settings. The main benefit is external validity: the findings tend to generalize better to everyday contexts because the research occurs in real conditions rather than in a tightly controlled laboratory.

However, the trade-off is internal validity. Without random assignment, there’s a greater risk of confounds and selection differences that could influence the outcome. That’s why these designs aren’t as strong for proving causality as true experiments.

So, when manipulation is unethical and you want results that reflect real-life situations, quasi-experimental designs are appropriate and offer better external validity.