One main strength of Milgram's (1963) study was the high level of control used in this study. All participants experienced the same procedure and used the same equipment. The experimenter followed a script when explaining the task to the participants, and he also used the same standardised verbal prompts to encourage the participant to continue with the experiment, for example "the experiment requires that you continue." This means that the results are highly likely due to the effect of the independent variable (the pressure to obey), as opposed to studies with low control where results may often be due to extraneous variables. Ultimately, this means that the results could be generalised to a wider population, as we expect others to behave the same when put in situations where they must obey an authority figure.However, one weakness of this study is the lack of ethical consideration, particularly with regards to the participants' well-being. The participants in this study were told that they were going to be inflicting increasing levels of pain on another individual, and they could hear the sounds that the other individual made when receiving the shocks. Although they were not really inflicting pain, the participants reported feeling guilty and disturbed about, many of them at point in the experiment asking if they really had to continue this. There were also physical signs of stress shown by the participants, many of them shaking and sweating and one even crying at the knowledge that he was being forced to harm another. The immediate psychological effects that this experiment had could make the participants question what kind of person they are for inflicting such pain on another, which could be damaging for them and could even develop into a form of PTSD.