Teacher and Student Perceptions of Jump Quality: Deriving Objective Thresholds and Examining Rating Agreement in...

Background: Jumping is fundamental to vocational ballet training, yet physiological metrics are rarely assessed, leaving teachers and students reliant on subjective appraisals of jump quality. The accuracy of these perceptual judgements and their relationship to objective performance remain largely unexplored in young dancers. Purpose: To establish teacher-referenced countermovement jump (CMJ) thresholds corresponding to 1-5 ordinal ratings of jump quality in adolescent ballet dancers, and to examine student-teacher agreement patterns across sex and developmental stages. Methods: In a cross-sectional study of 133 vocational ballet students (84 females, 49 males; aged 11-19 years), teachers rated jump quality (1-5 scale) during standardized ballet sequences while students self-rated their abilities. CMJ height was assessed via Optojump. Receiver operating characteristic analysis with Youden's J optimization derived sex- and age-specific thresholds mapping teacher ratings to CMJ cut-points (cm). Student-teacher agreement was evaluated using quadratically weighted Cohen's k, confusion matrices, and McNemar tests. Analyses were stratified by sex and year-group (Y7-9, Y10-11, Y12-14). Results: Teacher-anchored thresholds increased with age and were higher in males (M Y10-11: 31.5-37.6 cm across rating categories; F Y10-11: 25.6 cm for ratings ≥4). CMJ demonstrated moderate discriminative ability (AUCs 0.41-0.88), indicating meaningful but incomplete correspondence with teacher ratings. Student-teacher agreement was partial (k_w = 0.05-0.55), with no directional bias in females but systematic patterns in males: teachers rated older males approximately one category higher than self-ratings (median difference = 1, P < .01). DeLong tests confirmed consistent discriminative ability across groups (P > .05). Sensitivity analyses verified robustness to leg-length adjustment, teacher clustering, and outlier exclusion. Conclusions: Sex- and age-specific CMJ thresholds provide practical benchmarks for calibrating subjective judgements in ballet pedagogy. Moderate AUCs reflect the multi-dimensional nature of jump quality, encompassing aesthetic and technical elements beyond vertical displacement. Systematic student under-rating relative to teacher assessment, particularly among older males, highlights the need for pedagogical strategies supporting realistic self-appraisal alongside technical development.