Ecological Validity

Ecological validity is the degree of correspondence between the research conditions and the phenomenon being studied as it occurs naturally or outside of the research setting. For example, if one is studying how students solve simple arithmetic problems, the ecological validity of the study depends on how closely the research design corresponds to the [Page 564]conditions in which students encounter and solve such problems in their own lives. Weak ecological validity in the design and conduct of any research may be the result of overreliance on standardized experimental procedures (such as standardized test procedures), an inadequate definition of the phenomenon being studied, misunderstanding the phenomenon’s natural occurrence outside the research setting, a lack of sufficient resources, or the erroneous assumption that context does not affect behavior. This entry discusses why ecological validity is important in research, the development of the concept of ecological validity, and the conditions that are necessary for a study to be said to have strong ecological validity.

Strong ecological validity is a fundamental requirement for research to be meaningful or applicable to conditions outside of contrived research settings. Regardless of the cause, studies with weak ecological validity cannot be generalized to any actually existing phenomenon regardless of their external or internal validity. While sometimes confused with external validity, ecological validity is an independent criterion for good research. External validity measures usually do not demonstrate correspondence to naturally existing phenomenon because they only test correspondence to other research settings. High external validity and even meta-analyses of research results usually show only consistency within contrived research settings.

As with all other forms of validity, ecological validity cannot be answered with a simple “yes” or “no,” but only in degrees. Although it is a fundamental standard for good research, ecological validity is always a goal we strive to attain and never something a study definitively has or lacks. Instead, we should discuss the ecological validity of research along a spectrum, such as from very strong to very weak.

The standard of ecological validity is generally credited to the work of Kurt Lewin and Egon Brunswik in the 1940s. Both were influential psychologists, Lewin being one of the founders of social psychology. Lewin’s theory of ecological validity is the one closest to how we use the term today, while Brunswik’s concept of ecological validity was particular to visual processing and is generally only used by Brunswikians.

The modern principles of ecological validity were given shape in the 1970s by Urie Bronfenbrenner and Ulric Neisser. Bronfenbrenner was a developmental psychologist with significant influence on research in education and assessment, while Neisser is considered one of the founders of cognitive psychology. Both were dismayed by how the rise in laboratory experiments in psychology had created a disconnect between the conditions under which a phenomenon was studied and how the phenomenon actually occurred outside the laboratory.

Bronfenbrenner laid out 20 propositions that describe how research in developmental psychology and education should be conducted to ensure ecological validity. The first three of his propositions became the foundation for nearly every theory of ecological validity that

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