Research-based knowledge in psychology: what, if anything, is its incremental value to the practitioner?

This essay reflects an ongoing dialogue between a clinician versed in mainstream psychological research and theory, and a social psychologist with experience both as a researcher and contributor to applied undertakings in various domains about the "incremental value" of research-based knowledge-that is, its value beyond that provided by the other sources of knowledge available to the practitioner. These sources include knowledge about the needs and coping strategies of all human beings, as well as knowledge both about the specific life circumstances of those one is seeking to help, and knowledge about language and culture. Examples from the clinical practice of the first author are offered, coupled with in-principle arguments about the underspecified and contingent nature of research-based generalizations. By way of rebuttal, examples of arguably useful findings are provided by the second author-especially findings that serve as correctives to biases in lay psychology (notably unwarranted "dispositionism") and to widespread shortcomings in judgment and decision-making (particularly, Kahneman and Tversky's work on "prospect theory" ). Both authors agree on the value of a "bricoleur" treatment strategy that relies on careful attention to the specifics of the case at hand and avoids one-size-fits-all applications of theory and prior research, and both agree that research-based findings are more useful in predicting behavior and designing intervention strategies that apply to groups and large samples of individuals rather than single actors. A concluding discussion focuses on necessary criteria and strategies for increasing the usefulness of laboratory and field research for the practitioner.