Inferring signs from purposeful samples: The role of context in competency assessment.

When determining what types of ratings to use to evaluate medical student competence, medical education has shown too little nuance in considering the degree to which particular characteristics are likely to be generalisable, approaching the issue in an all-or-none manner. Smith's distinction between universals, occupationals and relationals offers a promising way forward that has implications for assessment, student selection and career choice.