Table 2

Unadjusted secondary outcomes at baseline, 8-week follow-up and 12-week follow-up, and estimated group difference adjusted for baseline measures and age

	Control	Intervention	β†	95% CI	p Value
	Mean (SD)‡	Mean (SD)‡	β†	95% CI	p Value
Patient Specific Functional Scale
Baseline	18.0 (5.8)	15.5 (5.9)
8-week	22.0 (4.3)	25.0 (4.0)	4.1	0.9 to 7.3	0.013*
12-week	23.1 (4.9)	26.1 (3.5)	4.0	0.8 to 7.2	0.014*
Roland Morris Disability Questionnaire
Baseline	3.4 (5.8)	4.1 (5.9)
8-week	2.6 (4.3)	1.2 (4.0)	−1.7	−2.8 to −0.6	0.003*
12-week	2.0 (4.9)	0.9 (3.5)	−1.4	−2.6 to −0.3	0.013*
Muscle endurance tests (s)
Back endurance test
Baseline	95.5 (21.1)	104.2 (41.3)
8-week	92.0 (34.6)	122.5 (33.9)	28.2	−0.5 to 56.9	0.054
Lower limb endurance
Baseline	38.1 (21.8)	45.6 (34.1)
8-week	47.2 (25.0)	65.8 (39.5)	20.9	2.0 to 39.7	0.031*
Static sitting kinematics (^o)
Lower lumbar angle
Baseline	4.9 (9.5)	0.0 (11.0)
8-week	7.1 (7.1)	−2.6 (6.9)	−9.6	−16.4 to −2.9	0.007*
Upper lumbar angle
Baseline	1.5 (9.2)	3.5 (6.8)
8-week	3.7 (6.4)	1.1 (8.7)	−3.0	−10.6 to 4.5	0.417
Ergometer kinematics (^o)
Lower lumbar angle excursion over drive phase§
Baseline	12.2 (7.8)	17.3 (15.0)
8-week	11.3 (7.3)	14.2 (12.7)	4.3	−3.2 to 11.8	0.261
Lower lumbar angle¶
Baseline	1.4 (15.1)	−2.8 (24.7)
8-week	−3.6 (16.7)	1.3 (11.4)	2.1	−6.7 to 11.0	0.635
Upper lumbar angle excursion over drive phase§
Baseline	12.0 (9.4)	12.8 (9.0)
8-week	8.0 (4.2)	11.4 (8.5)	−0.5	−5.2 to 4.2	0.834
Lower lumbar angle¶
Baseline	3.6 (10.3)	5.7 (9.6)
8-week	6.8 (8.9)	3.4 (15.5)	−1.5	−11.7 to 8.8	0.775

†Difference in means adjusted for age and baseline level of measure.
‡Unadjusted means.
§Adjusted for minute.
¶Adjusted for phase and minute.