certain aspects of the study. Deception may include false cover stories, false participants (known as confederates or stooges), false feedback given to the participants, and other techniques that help remove potential obstacles to participation. The practice of deception has been challenged by psychologists who maintain that deception under any circumstances is unethical and that other research strategies (e.g., role-playing) should be used instead. Unfortunately, research has shown that role-playing studies do not produce the same results as deception studies, and this has cast doubt on their validity. In addition to deception, experimenters have at times put people in potentially uncomfortable or embarrassing situations (e.g., the Milgram experiment and Stanford prison experiment), and this has also been criticized for ethical reasons. Virtually all social psychology research in the modern day must pass an ethical review. At most colleges and universities, this is conducted by an ethics committee or institutional review board, which examines the proposed research to make sure that no harm is likely to come to the participants, and that the study's benefits outweigh any possible risks or discomforts to people participating. Furthermore, a process of informed consent is often used to make sure that volunteers know what will be asked of them in the experiment and understand that they are allowed to quit the experiment at any time. A debriefing is typically done at the experiment's conclusion in order to reveal any deceptions used and generally make sure that the participants are unharmed by the procedures. Today, most research in social psychology involves minimal risk, or no greater risk of harm than can be expected from normal daily activities or routine psychological testing. Replication crisis Many social psychological research findings have proven difficult to replicate, leading some to argue that social psychology is undergoing a replication crisis. A 2014 special edition of Social Psychology focused on replication studies, finding that a number of previously held social psychological beliefs were difficult to replicate. Likewise, a 2012 special edition of Perspectives on Psychological Science focused on issues ranging from publication bias to null-aversion which have contributed to the replication crisis. Some factors have been identified in social psychological research as contributing to the crisis. For one, questionable research practices have been identified as common. Such practices, while not necessarily intentionally fraudulent, often involve converting undesired statistical outcomes into desired outcomes via the manipulation of statistical analyses, sample sizes, or data management