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Table 1 Definitions of the outcome measures

From: Transfer of mode switching performance: from training to upper-limb prosthesis use

Outcome measure Category Representation in Fig. 4 Calculated for Description
Attempts Clinically relevant performance measures A1–A5 Pre- and post-test, training sessions Successful attempts, attempts resulting in a correct switch
Unsuccessful attempts, attempts not resulting in a switch
Number of attempts, number of attempts within a block. This measure was calculated for both successful and unsuccessful blocks
Time needed to switch Clinically relevant performance measures B Pre- and post-test The time needed to perform a correct switch. Calculated from the start of block till the moment a correct switch was detected. A shorter time needed to switch indicated better performance
Accuracy of switching Clinically relevant performance measures Computed from A1–A5 Pre- and post-test Percentage of the attempts that resulted in a correct switch, calculated per block. The higher the accuracy of switching, the better the performance
Amplitude Myosignal features C1, C2 Training sessions The height of the sEMG signal during a switch attempt. This measure was calculated for both sEMG signals separately and was averaged across the two (Amplitude = (C1 + C2) / 2)
Phasing Myosignal features D Training sessions The time difference between the peak amplitudes of both sEMG signals. Since ideally the peaks occur simultaneously, a smaller Phasing represents better performance
Width Myosignal features E Training sessions The duration between the start and end of a trigger command. The duration needed to remain below a 300 ms threshold in order for the algorithm to recognize it as a trigger. A shorter trigger duration reduces the likelihood for the algorithm to interpret the signal as an opening or closing command of the hand and thus reduces the chances of unintentional movement of the hand. Width was calculated based on the time between the myosignal that first reached the amplitude threshold (0.3) and the myosignal that last fell below this threshold. A smaller Width reflects better performance