Twenty years of bogus pipeline research: A critical review and meta-analysis.

The bogus pipeline (BPL), a procedure intended to improve the truthfulness of self-reports, was examined in terms of the validity of its effects, its optimal procedural format, and its appropriate domain of use. Social psychological research that has used the BPL is reviewed and meta-analyzed. Thirty-one studies were coded for effect size and relevant procedural characteristics. A significant mean BPL versus control condition effect was evident across these studies, indicating that the BPL engendered reliable effects consistent with a reduction in socially desirable responding. The BPL produced larger effects when task instructions required Ss to guess the BPLs output. These findings, coupled with previous indirect validation, provide reasonable documentation that the BPL shifts self-reports toward veracity. Past criticisms of the BPL are considered, and recommendations for its future use are made.