Visibility of the segments in the short axis view of the LV. The images
were separated by B-mode image quality (good, medium, poor). The number of
segments with each visibility score (1=clearly seen, 2=poorly seen, 3=not
visible) is expressed as a percentage of the total number of segments in each
image quality category. The height of the bars represent the median of the three
independent observers and the error bars show the interquartile range for each
score category in each image quality category in sytole and diastole. The
p-values were (a) 1 in systole and diastole in good quality
images, (b) 0.45 and 0.64 in systole and diastole, respectively, in medium
quality images, and (c) 0.047 and 0.0078 in systole and diastole, respectively,
in poor quality images. The kappa statistics indicate fair agreement among the
reviewers (κ = 0.30).