Optimizing Reliability of Digital Inclinometer and Flexicurve Ruler Measures of Spine Curvatures in Postmenopausal Women with Osteoporosis of the Spine: An Illustration of the Use of Generalizability Theory

Table 5

Reliability of spine curvature measures acquired in triplicate by 2 raters in 9 postmenopausal women with osteoporosis of the spine estimated using generalizability theory (G-Theory) and classical test theory (CTT).

Measures of spine curvature	Inter-trial reliability		Inter-rater reliability
	G-theory	CTT	G-theory	CTT
Cervicothoracic angle
Reliability coefficient	0.960	0.960	0.566	0.601
SEM (degrees)	2.281	2.040	7.505	7.091
Thoracolumbar angle
Reliability coefficient	0.958	0.964	0.726	0.722
SEM (degrees)	3.090	2.703	7.868	7.786
Lumbosacral angle
Reliability coefficient	0.942	0.946	0.637	0.630
SEM (degrees)	2.498	2.367	6.223	6.213
Kyphotic index
Reliability coefficient	0.956	0.959	0.921	0.920
SEM	1.097	1.040	1.474	1.461
Lordotic index
Reliability coefficient	0.840	0.837	0.746	0.768
SEM	1.427	1.390	1.794	1.701

SEM: standard error of the measurement provides an estimate of absolute reliability and is expressed in the same units as the measure.