Table 1.

Baseline description of participants by treatment group

	Thrust SM (n=72)		Non-Thrust SM (n=72)		Wait List Control (n=48)
	n	%	n	%	n	%
Demographics
Male	38	53	39	54	26	54
Age (years), mean (SD)	40.5	(10.0)	39.3	(8.8)	40.3	(9.5)
White	63	88	63	88	43	90
Hispanic or Latino	7	10	5	7	1	2
At least some college	49	68	46	64	38	79
Married or living with partner	43	60	44	61	23	48
Employed	60	83	60	83	39	81
Health insurance	46	64	46	64	28	58
Currently smoke cigarettes	30	42	27	38	24	50
Obese (BMI>30)	38	53	25	35	24	50
LBP History
QTF Diagnostic classification
1: Pain without radiation	50	69	44	61	28	58
2: Pain + radiation to proximal extremity	14	19	19	26	12	25
3: Pain + radiation to distal extremity	8	11	9	13	8	17
Duration of LBP episode
4 weeks-3 months	7	10	1	1	3	6
3-12 months	16	22	14	20	13	27
>12 months	49	68	57	79	32	67
History of previous LBP episodes	52	72	57	79	40	83
History of previous spinal manipulation	56	78	62	86	38	79
Baseline Outcomes
Roland Morris Disability Questionnaire, mean (SD)	9.8	(3.6)	9.5	(3.0)	9.7	(3.0)
Average LBP during past week (VAS, mm), mean (SD)	56.5	(22.5)	54.5	(20.3)	56.1	(19.6)
Fear-Avoidance Beliefs Questionnaires
Physical Activity Subscale, mean (SD)	15.4	(4.8)	15.1	(4.8)	17.3	(4.5)
Work Subscale, mean (SD)	13.1	(9.7)	13.5	(9.2)	13.9	(10.9)
Short Form-36 Health Survey
Physical Health Summary Measure, mean (SD)	35.2	(7.7)	36.6	(7.9)	36.5	(7.1)
Mental Health Summary Measure, mean (SD)	45.4	(10.7)	47.4	(10.1)	45.6	(10.2)

BMI – body mass index; QTF – Quebec Task Force Classification for Spinal Disorders; LBP – low back pain; VAS – visual analog scale.