Table 1.

Comparative Reliability of Preoperative Sacral Slope and Postoperative Cup Version Measurements in Different Positions

	Preoperative sacral slope									Postoperative cup version
	Standing			Supine			Lateral decubitus			Standing			Cross-table lateral
	Reading 1	Reading 2		Reading 1	Reading 2		Reading 1	Reading 2		Reading 1	Reading 2		Reading 1	Reading 2
Inter-observer reliability	0.997	0.992		0.991	0993		0.995	0.994		0.995	0.991		0.98	0.976
Intra-observer reliability	0.995, 0.994			0.995, 0.989			0.994, 0.996			0.992, 0.992			0.981, 0.972
P-value	<0.0005	<0.0005		<0.0005	<0.0005		<0.0005	<0.0005		<0.0005	<0.0005		<0.0005	<0.0005