ecological validity

Meaning: Ecological validity is the degree to which a study's setting, tasks, and procedures resemble real-life conditions, so its results can be expected to hold outside the research setting. It is a kind of external validity (generalizability). Tightly controlled laboratory tasks, such as memorizing word lists, tend to have lower ecological validity; field studies and naturalistic observation tend to have higher.

On the MCAT: A passage describes a lab experiment on something like bystander behavior or eyewitness memory, then asks for a limitation or a way to improve the design. A common answer is that the artificial setting may not reflect real behavior, so a field study would raise ecological validity. Expect a tradeoff: more realism usually means less control over confounding variables, which can weaken internal validity.

Common confusion: Students confuse it with internal validity or with sample representativeness. Internal validity asks whether the independent variable caused the outcome; ecological validity asks whether the situation is realistic enough to generalize. A study can be high in one and low in the other, and a random, representative sample does not fix an unrealistic setting.