Table 1.

RSEI trend classification.

	Z	RSEI trend
≥ 0.0005	≥ 1.96	Significant rise (SR)
≥ 0.0005	−1.96 ≤ Z < 1.96	No significant rise (NSR)
-0.005 ~ 0.005	−1.96 ≤ Z < 1.96	Relatively stable (RS)
≤−0.0005	−1.96 ≤ Z < 1.96	No significant decrease (NSD)
≤−0.0005	≤−1.96	Significant decrease(SD)