A comprehensive instrument for evaluating advanced volleyball techniques in sport science students: design, reliability, and validity

Background: The enhancement of sports performance, particularly in volleyball, relies on the use of valid and well-developed measurement tests. Numerous studies have thus developed tests tailored to different skill levels to accurately assess athletes' abilities. However, the existing instruments for measuring volleyball techniques have yet to fully address the needs of advanced levels, especially in assessing technical skills among sports science students at the advanced stage. Purpose: This study aims to develop a comprehensive volleyball skill assessment instrument for advanced-level sports students, focusing on four key techniques: serving, underhand passing, overhand passing, and spiking. The instrument underwent rigorous testing to ensure its validity and reliability, with particular attention to construct validity across different phases and indicators. Methods: The study used a development research design based on the Plomp model, involving 51 male students from the Advanced Volleyball Course at Universitas Negeri Padang. Five expert judges assessed the instrument's feasibility before implementation. The research process included preliminary research, prototyping, and assessment phases. Expert opinions were collected using a Likert scale questionnaire via the Delphi technique. Validity and reliability were analyzed using SPSS version 25, focusing on internal and external validity coefficients and Cronbach's Alpha. Results: The instrument showed high reliability, with Cronbach's Alpha values consistently above 0.87. Construct validity tests confirmed the assessment's validity, with scores indicating a strong correlation between evaluated indicators and overall skill proficiency. Conclusion: The developed instrument is a reliable and valid tool for assessing advanced volleyball skills, offering a standardized method for educators and coaches to evaluate and enhance sports science students' performance. The study highlights the importance of phase-by-phase analysis in skill assessment for more effective volleyball training programs.