Electrocardiogram Reference Ranges Derived from a Standardized Clinical Trial Population

Accurate assessment of electrocardiographic intervals is crucial for routine patient care and clinical research. This assessment requires well-characterized reference ranges. This article provides a complete set of reference ranges for numerical electrocardiogram (ECG) parameters (PR, QRS, QTc intervals, and heart rate). The reference ranges are derived from a large clinical trial patient population using a standardized ECG acquisition and analysis system (N = 15,039). The reference ranges are stratified by important prognostic factors: age, sex, and overall ECG evaluation at baseline (normal or abnormal). The proposed reference ranges may be useful for patient management and data analyses in clinical drug development. In addition, the article provides a QT correction formula to correct the QT interval for heart rate. This QT correction formula was shown to be superior to the Bazett and Fridericia corrections in a clinical trial population in the ability to minimize the correlation between QT and RR.