blandAltmanPlot (X, Y) draws, for each subject measured by both methods, the difference X - Y against the mean of the two measurements, with a solid line at the bias, the mean difference, dashed lines at the limits of agreement, and dotted lines at the bounds of the confidence interval of each. limitsOfAgreement computes them, and the options it takes, 'Multiplier' and 'Alpha', are passed on to it, as are X and Y, whose requirements it states. A pattern in the points, the differences growing with the mean for instance, is a sign that the limits, which assume one spread of differences throughout, do not describe the methods well.

blandAltmanPlot (ax, …) draws into the axes ax rather than the current axes.

H = blandAltmanPlot (…) returns the graphics objects drawn, in a row vector: the points, the lines at the bias, the lower limit and the upper limit, and the dotted pairs of lines of the intervals of the bias, the lower limit and the upper limit, each pair one line object. Each carries a DisplayName, so legend labels them.

See also: limitsOfAgreement, gardnerAltmanPlot

Source Code: blandAltmanPlot