Validity - Zimbardo et al study

• The study has high internal validity as the researchers had a degree of control over how the roles were assigned and gave the participants uniforms to help them adopt their social roles.
• The study is criticised for it's lack of ecological validity. Banuazizi & Movahedi (1975) argued participants were play-acting in the mock prison, not adopting a social role.
• McDermott (2019) argues the study has high ecological validity as the setting was very realistic for the participants.
• Reicher & Haslam (2006) replicated the study for the BBC and found that participants did not adopt the social roles of prisoner and guard. This suggests the study lacks temporal validity.
• The study lacks population validity as only male students from the USA were used. This does not represent the wider population.