What is the week-to-week, inter- and intraobserver variability of left ventricular dimensions measured by M-mode echocardiography in normal subjects and patients with valvular heart disease?
M-mode echocardiography provides highly reproducible measurements of left ventricular dimensions with minimal week-to-week, interobserver, and intraobserver variability.
The week-to-week, inter- and intraobserver variation in left ventricular echocardiographic measurements has been studied in 10 normal male volunteers and in five patients with stable valvular disease. A two-way analysis of variance showed no statistically significant variation either from week to week or between observers. Furthermore the within observer variation was minimal. Calculation of the coefficient of variation allowed confidence limits to be applied to each of the six ventricular measurements, thus providing ranges of variation in follow-up studies using M-mode echocardiography.
Ladipo et al. (1980) studied this question.