Compare methods

	Bystander Intervention Paradigm	Cover Story Deception
Field	Social Psychology	Social Psychology
Family	Process / pipeline	Process / pipeline
Year of origin	1968	1959
Originator	Bibb Latane & John Darley	Classic experimental social psychology
Type	Experimental paradigm for emergency helping	Methodological design controlling participant expectations
Seminal source	Latane, B., & Darley, J. M. (1968). Group inhibition of bystander intervention in emergencies. Journal of Personality and Social Psychology, 10(3), 215-221.	Festinger, L., & Carlsmith, J. M. (1959). Cognitive consequences of forced compliance. Journal of Abnormal and Social Psychology, 58(2), 203-210.
Aliases	Bystander Effect Experiment, Diffusion of Responsibility Paradigm, Emergency Helping Paradigm	Deception Design, Cover Story Method, Experimental Deception
Related	3	3
Summary	The bystander intervention paradigm, pioneered by Latane and Darley in 1968, experimentally demonstrates the bystander effect: the counterintuitive finding that individuals are less likely to help in an emergency when other people are present. In their classic studies a participant encounters a staged emergency -- smoke filling a room, a person apparently having a seizure, or a fall -- either alone or in the company of others (sometimes passive confederates). The dependent measures are whether and how quickly the participant intervenes. Helping reliably declines, and slows, as the number of bystanders increases, an effect Latane and Darley explained through diffusion of responsibility, pluralistic ignorance, and audience inhibition. They formalized the path to helping as a sequence of decisions, each of which the presence of others can derail. The paradigm reshaped understanding of prosocial behavior and emergency response.	Cover story and deception design is the methodological practice of concealing a study's true purpose behind a plausible false rationale so that participants behave spontaneously rather than in line with what they think the experimenter wants. Because people who guess a study's hypothesis may consciously or unconsciously alter their behavior -- the problem of demand characteristics -- social psychologists often present a cover story that misdirects attention, embed the real dependent measure within an apparently unrelated task, and, when necessary, use additional deceptions such as confederates or false feedback. This approach made possible many of the field's classic findings on conformity, obedience, helping, and dissonance, where awareness of the true question would have destroyed the phenomenon. Deception carries serious ethical obligations, requiring justification, minimization of harm, suspicion probing, and thorough debriefing, which contemporary practice and ethics codes strictly govern.