Watch the following clip to introduce Rosenhan’s (1973) famous study and get the ball rolling on the link between deviance from statistical norms, deviance from social norms and the validity and reliability of diagnosis: https://vimeo.com/112905501
Two of the main tools for diagnosis are “the DSM and the ICD” both of which have been revised many times. You need to know about about both of these systems before you can get to grips with whether they are valid or reliable.
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