What research design should I choose if I want to explain or understand the causes of behavior or create change in the "real world"?

• Quasi-experimental designs

We’ve seen that control is an essential aspect of experimental research designs. Sometimes, however, researchers cannot control all aspects of a situation, for example, when they conduct research in the "real world" rather than a lab. When researchers seek to control some aspects of an experimental situation, but cannot control all important aspects, they may conduct a quasi-experiment. Quasi means "almost"; therefore, quasi-experiments are "almost-experiments."

How do quasi-experiments differ from "true" experiments?

How do I conduct a quasi-experiment?