Including EMG signals and historical information in the real-time control system resulted in significantly lower classification error ( mean , @ % -LSB- @ % CI , @ % -@ % -RSB- ) across a mean of @ steps ( range , @-@ steps ) compared with using mechanical sensor data only ( mean , @ % -LSB- @ % CI , @ % -@ % -RSB- ) across a mean of @ steps ( range , @-@ steps ) , with a mean difference between groups of @ % ( @ % CI , @ % -@ % -RSB- ( P = @ ) .