ABSTRACT
The dominant approach to personality assessment in sport psychology is through self-report measures. However, this is despite a consensus that multi-method assessments benefit the reliability and validity of personality measurement. The contributions on personality in the encyclopedia provide an outstanding overview of where the research literature is, and much more is known about the influence of individual differences in personality in relation to sport and exercise behaviour. Informant reports of personality are typically provided by well-known acquaintances and can be aggregated across observers to increase their reliability. A researcher interested in studying the effect of personality traits on the performance of elite soccer players is unlikely to have the necessary access to these players to administer a detailed self-report personality questionnaire. A clearer picture of how individual difference factors can affect sport and exercise performance is also likely to be gained through greater understanding of the biological basis of personality traits.
