“…12,16,17,26 We found that PhrenAmp and the corresponding lower limit of normal were overall lower than in previous studies (0.38 mV versus 0.66 m, 0.70 mV, and 0.65 mV). 20,21,27 We found a slightly lower value of mean CMAP duration than in the studies of Chen, Resman-Gaspersc, and Podnar (16.05 versus 19.4 and 21 ms respectively). 20,21 These differences may be explained by the larger number of participants in our study.…”