		Pain level^a at V2, N (%)
V1, V2	Pain level^a at V1	0 - 1	2 - 3	p-value
7, 15	0 - 1	28 (100)	0	0.008
7, 15	2 - 3	7 (70.0)	3 (30.0)	0.008
15, 30	0 - 1	34 (100)	0	0.16
15, 30	2 - 3	2 (66.7)	1 (33.3)	0.16
30, 60	0 - 1	34 (100)	0	-
30, 60	2 - 3	1 (100)	0	-
60, 90	0 - 1	28 (100)	0	-
60, 90	2 - 3	0	0	-
90, 120	0 - 1	23 (100)	0	-
90, 120	2 - 3	0	0	-