Table 1.

Demographic and clinical characteristics at baseline

Characteristic	Chinese (N = 312)						International (N = 854)
	Placebo (n = 141)			Pregabalin (n = 171)			Placebo (n = 273)			Pregabalin (n = 581)
	All	Moderate pain	Severe pain	All	Moderate pain	Severe pain	All	Moderate pain	Severe pain	All	Moderate pain	Severe pain
Number of patients, n (%)	141	90	51	171	114	57	273	149	124	581	296	285
	(100)	(63.8)	(36.2)	(100)	(66.7)	(33.3)	(100)	(54.6)	(45.4)	(100)	(50.9)	(49.1)
Male, n (%)	80	49	31	87	56	31	133	71	62	264	128	136
	(56.7)	(54.4)	(60.8)	(50.9)	(49.1)	(54.4)	(48.7)	(47.7)	(50.0)	(45.4)	(43.2)	(47.7)
Age, years, mean (SD)	64.4	64.0	64.9	64.9	64.2	66.3	71.3	70.2	72.7	71.0	70.7	71.2
	(9.1)	(9.3)	(8.8)	(8.5)	(8.7)	(7.8)	(10.7)	(11.1)	(10.2)	(10.5)	(10.9)	(10.1)
Race, n (%)
White	0	0	0	0	0	0	270	147	123	567	289	278
							(98.9)	(98.7)	(99.2)	(97.6)	(97.6)	(97.5)
Black	0	0	0	0	0	0	0	0	0	4	1	3
										(0.7)	(0.3)	(1.1)
Asian	141	90	51	171	114	57	0	0	0	0	0	0
	(100)	(100)	(100)	(100)	(100)	(100)
Other	0	0	0	0	0	0	3	2	1	10	6	4
							(1.1)	(1.3)	(0.8)	(1.7)	(2.0)	(1.4)
Baseline pain score, mean (SD)	6.3	5.5	7.8	6.1	5.2	7.9	6.7	5.6	8.0	6.8	5.6	8.0
	(1.3)	(0.8)	(0.6)	(1.5)	(0.8)	(0.9)	(1.5)	(0.9)	(0.9)	(1.5)	(0.9)	(0.8)
Baseline PRSI	4.7	4.0	5.9	4.1	3.4	5.7	4.6	3.9	5.5	4.8	3.8	5.9
score, mean (SD)	(2.0)	(1.9)	(1.8)	(2.5)	(2.0)	(2.6)	(2.6)	(2.1)	(3.0)	(2.6)	(2.1)	(2.5)

Notes: Mean pain scores were based on an 11-point NRS, where 0 = no pain and 10 = worst possible pain. PRSI scores were based on an 11-point NRS, where 0 = pain does not interfere with sleep, and 10 = pain completely interferes with sleep. Patients categorized as having moderate pain had mean pain scores of ≥4 to <7 at baseline. Patients categorized as having severe pain had mean pain scores ≥7 to 10 at baseline. Patients with mild pain (mean pain score <4) were excluded from the study.

Abbreviations: NRS, numeric rating scale; PRSI, pain-related sleep interference.