title: Methodological variation in systolic time intervals.
abstract: Systolic time intervals (STI) were recorded six times in 12 male students. All 72 recordings were measured twice by a physician and once by two nurses. By comparing these measurements an intra- and interobserver (= methodological) variation was obtained. For measured parameters (QS2- interval and LVET) variation was less than 2%. For calculated parameters the variation was larger, but did not reach the level of statistical significance. Methodological variation was smaller than physiologic variation. The internal consistency was almost perfect for measured parameters and only slightly worse for calculated parameters.
mesh_terms: D000328:Adult; D002302:Cardiac Output; D006334:Heart Function Tests / Q000379:methods; D006801:Humans; D008297:Male; D009200:Myocardial Contraction; D013318:Stroke Volume; D013599:Systole