Test-Retest Reliability of the ALFAC Test Battery to Measure Aquatic Motor Skills Among Children Aged 6 to 12 Years

This study aimed to evaluate the test-retest reliability of the isolated aquatic motor tasks included in the newly developed ALFAC test battery for young children. Eighty children (7.7 ± 1.5 years) completed the ALFAC motor skills assessment on two separate days. The battery consisted of isolated aquatic motor tasks, including propulsion on the belly and on the back, submersion, floating, treading water, rotations (vertical [VR], lateral [LR], transversal [TR], forward [FR] and backward [BR]), entry, exit and breathing. Test-retest reliability was assessed using paired comparisons, intraclass correlation coefficients (ICC), Spearman correlations (ρ) and Cohen’s kappa coefficients, along with McNemar’s tests for categorical variables. Differences between test and retest were observed in the duration of propulsion on the belly and on the back, and in treading water tasks. These differences were supported by poor ICC values, particularly for treading water (ICC = 0.40), indicating moderate to poor reliability. In contrast, no differences were found for propulsion on the belly (m) or on the back (m), submersion (m), or floating (s), which demonstrated ICC values ranging from 0.54 to 0.82, reflecting moderate to good reliability. All outcome variables showed moderate to strong test-retest associations (ρ = 0.53–0.76), suggesting stable relative performance across time. For rotations, Cohen’s kappa values ranged from 0.43 to 0.64, indicating substantial agreement for VR and moderate agreement for LR, TR, FR and BR; however, systematic changes were identified for VR and TR. For the categorical ordinal tasks, moderate agreement was observed for entry and breathing, whereas the exit task demonstrated only fair agreement. Overall, the ALFAC battery provides a useful framework for assessing isolated aquatic motor skills, although refinements to specific tasks could increase its reliability.