Table 3. Comparison between the standing and supine groups ($\overline{x}\pm s$).

Measurement	PI (°)	PT (°)	SS (°)	LL (°)
Standing	58.22±12.369	20.64±9.079	37.61±10.157	50.20±12.791
Supine	55.67±11.694	14.03±7.489	41.65±9.168	50.44±11.658
t value	7.718	12.516	−6.381	−0.340
P value	<0.001	<0.001	<0.001	0.734
Cohen d value	0.212	0.794	0.418	0.020

Paired t-test, P<0.05. The Cohen d value is the result of post hoc power analysis: 0.2≤ small effect <0.5, 0.5≤ medium effect <0.8, large effect ≥0.8. LL, lumbar lordosis; PI, pelvic incidence; PT, pelvic tilt; SS, sacral slope.