12-lead ECG Manual Measurement 12-lead ECG Computer Measurement 7-lead Derived ECG Telemetry Lead II
Rate (beats/min) 85.49 ±22.35 86.03 ± 22.72 85.45 ±19.74 85.86 ± 20.62
RR (msec) 756.30 ± 231.27 741.36 ± 184.50 741.06 ± 193.52
QRS duration (msec) 95.45 ± 21.08 93.76 ± 21.12 96.97 ± 20.23 95.45 ± 21.37
PR duration (msec) 166.45 ± 26.02 158.40 ± 33.44 170.97 ± 24.68 167.00 ± 24.52
QT interval (msec) 401.21 ± 66.09 398.60 ± 64.80 388.18 ± 64.64 382.12 ± 60.71
Dispersion of QT (msec) 37.88 ± 16.73 25.45 ± 16.41
QTc (Bazett) (msec) 467.49 ± 50.91 464.15 ± 39.42 454.05 ± 49.41 447.87 ± 47.33
QTc (Fredericia) (msec) 442.82 ± 47.88 429.80 ± 49.93 423.60 ± 46.34
QTc (Hodges) (msec) 445.82 ± 48.52 432.74 ± 47.57 427.37 ± 44.38
QTc (Framingham) (msec) 438.74 ± 44.01 428.01 ± 46.73 422.00 ± 42.53