Published research findings are sometimes refuted by subsequent evidence, says Ioannidis, with ensuing confusion and disappointment.

Mediating variables are prominent in psychological theory and research. A mediating variable transmits the effect of an independent variable on a dependent variable. Differences between mediating variables and confounders, moderators, and covariates are outlined. Statistical methods to assess mediation and modern comprehensive approaches are described. Future directions for mediation analysis are discussed.

A controversy has arisen over the "interpersonal simulations" used by Bern to support his contention that his self-perception theory accounts for cognitive dissonance phenomena. Specifically, the critics challenge the implication of his analysis that the premanipulation attitudes of subjects in dissonance experiments are not salient in their postmanipulation phenomenology. The present investigation answers this challenge by demonstrating that subjects in a typical forced-compliance experiment are not only unable to recall their premanipulation attitudes correctly, but they actually perceive their postmanipulation attitudes (...) to be identical to their premanipulation attitudes. Accordingly, they do not perceive any attitude "change." The epistemological aspects of the interpersonal simulation methodology are also discussed. (shrink)