Table 2.

Reproducibility of the step‐wedge method by repeated analysis on same dataset (10 times) and trending behavior of our two Hi•Art II machines (averaged) during a three‐year period (August 2007 to October 2010). Number of measurements in this period was 65 per machine.

Item	Reproducibility (1SD)	Trending Data (1SD)
Couch speed overall dev (%)	0.03	0.1 (mean 0.4)
Couch speed level dev (%)	0.14	0.2
Energy D20/D10 (%)	$<0.1$	1.0
Laser transverse (mm)	0.03	0.4
Laser sagittal (mm)	$<0.01$	0.6
Field width (mm)	0.04	0.15
Abutment mismatch (mm)	0.1	0.2 (mean $-0.4$)