Validity and reliability of the Simple Motor Competence-check for Kids (SMC-Kids).

Objectives: To examine the validity and reliability of the Simple Motor Competence-check for Kids (SMC-Kids), which was developed to assess motor development in preschool children.

Design: A cross-sectional and repeated-measures design.

Methods: To assess validity, 71 children aged 4-6 years completed the Test of Gross Motor Development-3 (TGMD-3) and SMC-Kids (10 m shuttle run and paper ball throw). For inter-rater reliability, 91 children aged 3-6 years performed the SMC-Kids test, twice, by two different raters. To evaluate intra-rater reliability and quantify improvements beyond measurement error, 53 participants were reassessed by the same rater 7-10 days later.

Results: Spearman's rho between the 10 m shuttle run and the TGMD-3 locomotor score was -0.51 (95 % CI: -0.31, -0.66), and between the paper ball throw and TGMD-3 ball skill score was 0.80 (95 % CI: 0.70, 0.87). Confirmatory factor analysis showed strong associations of the 10 m shuttle run and paper ball throw with latent variables of locomotor and object control skills, with factor loadings of -0.97 and 0.88, respectively. Both tests showed good-to-excellent inter-rater (ICC = 0.898-0.96) and intra-rater reliabilities (ICC = 0.882-0.974). The smallest worthwhile changes were 0.25 s for the 10 m shuttle run and 0.42 m for the paper ball throw, with double coefficients of variation of 0.46 s and 0.99 m, and MDC 95 of 0.82 s and 1.52 m, respectively.

Conclusions: SMC-Kids is a simple tool to quickly measure preschooler locomotor and object control skills without the need for special equipment or large spaces.