Table 5.

Means, standard deviations (SDs) of pain scores and pain score changes in the 3 studied groups, Wilcoxon signed-rank (within-group differences) and Mann–Whitney U (between-group differences) standardized test statistics, and P values in the 3 studied groups

	One hour after insertion of interventional AW (T1)	24 h after insertion of interventional AW (T2)	48 h after insertion of interventional AW (T3)	One week after insertion of interventional AW (T4)
	Mean (SD)	Mean (SD)	Mean (SD)	Mean (SD)
Group 1	3.10 (1.89)	4.65 (1.84)	4.55 (2.12)	2.40 (1.31)
Group 2	3.47 (1.90)	6.16 (1.57)	4.05 (1.65)	2.16 (1.30)
Group 3	3.84 (2.24)	5.63 (2.34)	4.53 (2.14)	2.05 (1.39)
Within-group differences in mean pain score changes at different time points (related samples Wilcoxon signed-rank test)
	Pain changes T1–T2 (standardized test statistics, P value)	Pain changes T2–T3 (standardized test statistics, P value)	Pain changes T3–T4 (standardized test statistics, P value)	Pain changes T1–T4 (standardized test statistics, P value)
Group 1	(2.80, P = 0.005)	(− 0.39, P = 0.700)	(− 3.40, P < 0.000)	(− 1.51, P = 0.132)
Group 2	(3.38, P < 0.000)	(− 3.76, P < 0.000)	(− 3.64, P < 0.000)	(− 2.57, P = 0.010)
Group 3	(3.21, P = 0.001)	(− 1.83, P = 0.067)	(− 3.65, P < 0.000)	(− 2.50, P = 0.012)
Between-group differences (Mann–Whitney U test)
	Pain changes T1–T2 (standardized test statistics, P value)	Pain changes T2–T3 (standardized test statistics, P value)	Pain changes T3–T4 (standardized test statistics, P value)	Pain changes T1–T4 (standardized test statistics, P value)
Groups 1 and 2	(− 2.20, P = 0.030)	(− 3.09, P = 0.002)	(− 0.36, P = 0.728)	(− 1.22, P = 0.235)
Groups 1 and 3	(− 0.54, P = 0.607)	(− 1.12, P = 0.270)	(− 0.61, P = 0.550)	(− 1.48, P = 0.149)
Groups 2 and 3	(− 1.80, P = 0.080)	(− 1.65, P = 0.109)	(− 1.22, P = 0.246)	(− 0.737, P = 0.470)

T1, 1 h; T2, 24 h; T3, 48 h; T4, 1 week after insertion of interventional AW