Scores on social identification scales supported observational data in revealing a significant statistical interaction between group and phase. Further analysis showed that social identification among the Prisoners increased significantly over time. On the other hand, social identification among the Guards declined as the study progressed, but not significantly.
- Source: Reicher, S. D., & Haslam, S. A. (2006). Rethinking the psychology of tyranny: The BBC Prison Study. British Journal of Social Psychology, 45, 1-40.