Abstract
Recently, ICH-E14 guidelines were published by the Ministry of Health, Labor and Welfare. As a result, an accurate and reliable QT interval measurement method is required in a clinical trial. We investigated the reliability of the computer assisted procedure using the tangent line method in QT interval measurement from the results of a training program for three laboratory technicians. In 12-lead electrocardiogram from 20 healthy volunteers, QT interval was measured twice by three trainee technicians for two beats of each lead (480 measurements). Averaged QT intervals measured by two expert technicians were used as a reference. Inter-observer difference (between each trainee data and the reference data) and intra-observer difference (between the first and the second measurements) were evaluated. The inter-observer differences for the three trainee technicians were 0.8+6.2 msec,0.1+5.7 msec, and 2.1+6.5 msec, and correlation coefficient of their measurement for two times was 0.94-0.97. The present semi-automated QT-interval measurement system, which depends on simple tangent line setting work, showed sufficient reliability and reproducibility in a short technician training program.
