Table 2.
Discriminative validity for the assessment of absolute (cm) and relative (% leg length) Lower Quarter Y Balance Test performance between trained (i.e., soccer players) and age-matched untrained (i.e., controls) youth
| Participants (N = 138) | Statistics | |||
|---|---|---|---|---|
| Soccer players (n = 69) | Controls (n = 69) | p-value (d) | AUC-value | |
| Right leg reach | ||||
| AT (cm) | 70.9 ± 7.6 | 67.2 ± 7.4 | .004 (0.49) | .63 |
| PM (cm) | 107.6 ± 8.5 | 101.1 ± 11.4 | <.001 (0.64) | .67 |
| PL (cm) | 103.9 ± 7.8 | 97.7 ± 10.2 | <.001 (0.69) | .69 |
| Left leg reach | ||||
| AT (cm) | 69.6 ± 7.5 | 66.0 ± 8.2 | .009 (0.45) | .64 |
| PM (cm) | 106.5 ± 8.2 | 99.5 ± 13.1 | <.001 (0.64) | .66 |
| PL (cm) | 103.7 ± 9.1 | 96.8 ± 12.2 | <.001 (0.65) | .68 |
| Right leg reach | ||||
| AT (% LL) | 78.9 ± 9.5 | 71.5 ± 7.3 | <.001 (0.87) | .74 |
| PM (% LL) | 119.5 ± 8.8 | 107.8 ± 12.1 | <.001 (1.11) | .78 |
| PL (% LL) | 115.6 ± 9.1 | 104.2 ± 11.5 | <.001 (1.10) | .78 |
| CS (% LL) | 104.6 ± 8.1 | 94.5 ± 9.4 | <.001 (1.16) | .80 |
| Left leg reach | ||||
| AT (% LL) | 77.5 ± 9.2 | 70.3 ± 7.3 | <.001 (0.86) | .74 |
| PM (% LL) | 118.5 ± 8.7 | 106.0 ± 12.3 | <.001 (1.17) | .79 |
| PL (% LL) | 115.5 ± 10.6 | 103.2 ± 12.3 | <.001 (1.08) | .77 |
| CS (% LL) | 103.8 ± 8.1 | 93.2 ± 9.6 | <.001 (1.21) | .81 |
Data are mean ± standard deviation. Absolute values (cm) are shown first followed by relative values (% LL). Cohen’s d [18] can be classified as being small (0 ≤ d ≤ 0.49), medium (0.50 ≤ d ≤ 0.79), or large (d ≥ 0.80). In accordance with Deyo and Centor [23], the AUC-value can lie between 0.5 (“no” discriminative validity) and 1.0 (“perfect” discriminative validity)
AT anterior, AUC area under the receiver operator characteristic (ROC) curve, CS composite score, LL leg length, PL posterolateral, PM posteromedial