Planning and execution time
The non-parametric Mann–Whitney U analysis for time to plan indicated a statistical group trend for task 2 (U = 50; p= 0.08). Children in the DS group took more time to make their first manual contact with the toys during task 2 compared to TD children (Figure 4). There were no other group differences for time to plan for task 1 and task 3.
For the execution time, we first compared the percentage of children in the DS and TD group with ‘execution time’ data, and it was not different for task 1 (DS = 76.92%, TD = 100%, ꭓ2 = 0.39,p = 0.53), task 2 (DS = 61.54%, TD = 92.31%, ꭓ2 = 0.8, p = 0.37), and task 3 (DS = 69.23%, TD = 69.23%, ꭓ2 = 0, p = 1). Execution data was not calculated for children who ended the task earlier (< 60 seconds) due to non-engagement or non-compliance. The non-parametric Mann–Whitney U analysis indicated a statistical group trend for the total execution time (U = 53; p = 0.1), such that children in the DS group (38.11 ± 8.1 seconds) took longer to complete the task compared to TD group (20.15 ± 2.27 seconds).