Electrophysiological testing aids the diagnosis of tremor and myoclonus in clinically challenging patients

•Polymyography contributes to a change in diagnosis in 37% of patients.•EPT, ET, FT and cortical myoclonus were most commonly confused clinically, and these diagnoses were rectified by neurophysiological testing.•The stepwise approach proposed includes assessment of contraction pattern, rhythm regularity, burst duration and evidence for cortical drive.