Bioethics Blogs

Could PhD students solve the replication crisis in psychology?


As many readers of this blog may know, in the last few years a “replication crisis” has caused intense soul searching in psychology – and particularly in social psychology. This crisis was sparked when several widely cited findings in psychology subsequently failed to replicate when tested by independent researchers (for some background see Earp and Trafimow’s paper here). This is – of course – a substantial problem because it severely limits the confidence we can have in psychological findings. For social psychological research this problem may be even graver, given that many of the topics studied – e.g. attitudes, prejudice, political voting – have direct implications for policy making. If we cannot have confidence in our findings, social psychology is in very hot water indeed.

To take an example from my own research field of social/moral psychology, in a highly influential study published in Science, Zhong and Liljenquist (2006) reported evidence of a “Macbeth Effect” whereby a threat to people’s moral purity leads them to seek, literally, to cleanse themselves. Seeking to expand upon these findings and explore whether they would be observed in different domains, my colleagues Brian Earp, Elizabeth Madva, and Kiley Hamlin attempted to replicate and extend this work. To their surprise, they were unable to replicate the original results. They then turned to me, and together we conducted a series of direct replications of Study 2 from Z&L’s seminal report. We used Z&L’s original materials and methods, investigated samples that were more representative of the general population, investigated samples from different countries and cultures, and substantially increased the power of our statistical tests.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.