Associations of locomotor task performance with static and dynamic balance in pre-school children aged 3-6 years: an age-adjusted cross-sectional study.

Objective: To examine the cross-sectional associations between field-based locomotor task performance and static and dynamic balance in preschool children aged 3-6 years, and to assess how alternative approaches to accounting for age affect the estimated correlations. Methods: We analyzed pre-intervention baseline data from a motor intervention project involving 60 children (30 boys and 30 girls) aged 3.4-5.7 years at a kindergarten in Yancheng, Jiangsu Province, China. Locomotor tasks comprised the 10-m shuttle run, standing long jump, consecutive two-footed jumps, and lateral movement; balance was assessed using the eyes-closed single-leg stance and balance-beam walk. Pearson correlations and 95% confidence intervals (CIs) were calculated. Sensitivity analyses included Spearman rank correlations, leave-one-out analyses, and within-age-group analyses. Model A adjusted for exact age and sex, whereas Model B adjusted for age group and sex. The Benjamini-Hochberg procedure was applied to nine primary comparisons. Results: In unadjusted analyses, all nine pairs of measures were exceptionally strongly correlated (|r| = 0.967-0.998). In Model A, eight associations remained statistically significant after correction, with the exception of the association between balance-beam time and 10-m shuttle-run time. All nine associations were significant in Model B. After further adjustment for exact age and sex within each age group, several correlations weakened or reversed direction.