Abstract:
Sport psychological training and coaching has become increasingly relevant in the context of youth promotion programs in soccer. Likewise, numerous sport psychologists are integrated into support frameworks at clubs and associations. Scientifically sound diagnostics of personality characteristics can be regarded as an important foundation for the optimization of such sport psychological work. The present dissertation examined the relevance of psychological personality characteristics in talented soccer players in order to provide an empirical basis for the application of psychological diagnostics. For this purpose diagnostics of personality characteristics were implemented in the talent development program of the German Soccer Association. In accordance with previous research in sport science and psychology, a stepwise procedure was used to examine the prognostic value of personality characteristics. Taking into consideration a multidimensional, domain-specific, dynamic, and prospective understanding of talent, this procedure comprised four steps, which were addressed in three empirical studies as part of this dissertation. For the purpose of selecting potentially relevant predictors of soccer talent (Step 1), an analysis of the literature on psychological characteristics in talent research was conducted. Subsequently, the characteristics were presented to experts in science and soccer, whose task was to evaluate their importance for soccer performance. On this basis, psychological personality characteristics were selected that could be assigned to the areas of motivation, volition, self-referential cognition, and emotion. Regarding the personality characteristics’ assessment (Step 2), established sport-specific questionnaires were identified and the individual scales were modified in terms of soccer-specific and age-appropriate adaptations. Study 1 examined whether the personality characteristics of U12 soccer players could be assessed based on scientifically sound diagnostics. This study demonstrated that the modified questionnaires show satisfactory psychometric properties in terms of reliability and validity. Furthermore, these findings revealed small effects of socially desirable responding that should be further considered. With respect to development over time (Step 3), Study 2 provided useful insights into the stabilities and changes of psychological personality characteristics across the U12 to U14 age classes. Moderate differential stabilities imply that, to a certain degree, the relative ordering of individuals within such characteristics changes over time. Small mean- and individual-level changes indicate that no major developmental effects seem to occur in such personality characteristics during early adolescence. An analysis of structural stability provided empirical evidence concerning the complex interplay between various personality characteristics over time. Finally, Study 3 examined the relationship of U12 players’ personality characteristics with current and future performance criteria (Step 4). Cross-sectional analyses demonstrated that these characteristics – except for self-referential cognition – were empirically unrelated to motor performance. Furthermore, these analyses revealed small but relevant associations with the players’ overall performance as subjectively rated by their coaches. Prospective analyses indicated that U12 players’ personality characteristics explained significant proportions of the players’ performance level four years later in the U16 age class. Against the backdrop of a stepwise procedure in talent research, the present dissertation provided new insights into the relevance of psychological personality characteristics in talented soccer players. Building on these findings, this work identified avenues for future research and highlighted conclusions for sport psychological work in the context of talent identification and development.