Relations of psychological characteristics and team performance level in female volleyball players aged 12 to 15 years (U15)

Aim: To validate the Psychological Skills Inventory for Sport – Youth (PSIS-Y) questionnaire on a sample of youth Croatian female volleyball players, and to determine psychological characteristics of players aged 12 to 15 years, as well as possible differences according to team (competitive) performance level in variables: motivation, self-confidence, anxiety control, mental preparation, team emphasis, and concentration. Methods: The sample included 328 participants from 28 clubs competing at the national volleyball championship. We used the PSIS-Y questionnaire consisting of 44 items in 6 dimensions. Data analysis included validation of the questionnaire, descriptive parameters, and ANOVA to determine the differences in psychological dimensions between players at different performance levels, with the significance level set at P≤0.05. To determine the common effect of all the measured variables in differentiating the performance level between the groups of players, a multivariate procedure of discriminant analysis was used. Results: The participants showed a high level of motivation, medium levels of concentration, self-confidence, anxiety control, and a low level of mental preparation. According to team performance level, significant differences were found in concentration (P=0.001), anxiety control (P=0.002), mental preparation (P=0.002), and motivation (P=0.034). The applied discriminant analysis yielded two statistically significant discriminant functions: the first function (χ2=27.54; P=0.002) differentiated the group of players with the highest index of team performance level from the groups with lower indices, whereas the second function (χ2=10.39; P=0.034) differentiated the group of players with the lowest index from the three more successful groups due to higher levels of motivation and anxiety control. Conclusion: In comparison to previous findings, a decline in correlation between most psychological skills of youth female volleyball players and different levels of competitive team performance is noticed. This negative trend may be influenced by the increased importance of competition and an increased pressure put on youth players by their environment