Comparison 1: SMT vs recommended therapies
Time measurement	Difference in effect (95% CI)	# studies	N	Quality of the evidence (and reason for downgrading)
Outcome: Quality of life: Physical Component Scale of SF36 and SF12 combined
1 month	MD -0.6, 95% CI -1.4 to 0.1	4	844	High
3 months	MD -0.2, 95% CI -1.0 to 0.7	3	967	High
6 months	MD -0.3, 95% CI -1.5 to 0.91	4	688	High
12 months	MD 0.1, 95% CI -0.8 to 1.0	4	1055	High
Outcome: Mental Component Scale of SF36 and SF12 combined
1 month	MD 0.4, 95% CI -0.4 to 1.2	4	844	High
3 months	MD 0.8, 95% CI -0.0 to 1.6	3	967	High
6 months	MD -0.1, 95% CI -1.4 to 1.2	4	688	High
12 months	MD 0.5, 95% CI -0.9to 2.0	4	1055	High
Outcome: Recoverya: Yes vs No
1 month	OR 1.3, 95% CI 0.9 to 1.9	2	499	Moderate (inconsistency)
3 months	OR 1.2, 95% CI 0.8 to 1.8	3	538	Moderate (inconsistency)
6 months	OR 1.1, 95% CI 0.8 to 1.6	3	651	Moderate (inconsistency)
12 months	OR 0.8, 95% CI 0.5 to 1.2	2	445	Moderate (inconsistency)
Outcome: Medication Usea: Yes vs No
1 month	OR 0.7, 95% CI 0.5 to 1.0	3	646	Moderate (inconsistency)
3 months	OR 0.7, 95% CI 0.4 to 1.2	3	626	Moderate (inconsistency)
6 months	OR 0.5, 95% CI 0.3 to 0.9	3	593	Moderate (inconsistency)
12 months	OR 0.7, 95% CI 0.3 to 1.3	3	582	Moderate (inconsistency)
Outcome: Return to worka: Yes vs No
1 month	Not enough data
3 months	OR 1.0, 95% CI 0.5 to 1.9	3	190	Low (inconsistency, imprecision)
6 months	OR 0.6, 95% CI 0.3 to 1.3	3	189	Low (inconsistency, imprecision)
12 months	OR 1.3, 95% CI 0.6 to 2.7	3	180	Low (inconsistency, imprecision)
Outcome: Satisfactiona: Yes vs No
1 month	OR 0. 8, 95% CI 0.4 to 1.6)	2	319	Low (inconsistency, imprecision)
3 months	OR 6.6, 95% CI 1.5 to 29.9	2	429	Low (inconsistency, imprecision)
6 months	Not enough data
12 months	Not enough data
Comparison 2: SMT vs non-recommended therapies
Outcome: Quality of life: Physical Component Scale of SF36 and SF12 combined
1 month	MD 0.4, 95% CI -0.8 to 1.6	3	345	Low (inconsistency, imprecision)
3 months	Not enough data
6 months	MD -0.1, 95% CI -2.5 to 2.2	2	202	Low (inconsistency, imprecision)
12 months	Not enough data
Outcome: Quality of life: Mental Component Scale of SF36 and SF12 combined
1 month	MD 1.0, 95% CI -3.1; 5.2	3	345	Low (inconsistency, imprecision)
3 months	Not enough data
6 months	MD 1.7, 95% CI -0.6; 4.0	2	202	Low (inconsistency, imprecision)
12 months	Not enough data
Other outcomes not enough data
Comparison 3: SMT vs sham SMT
No results only data of one study
Comparison 4: SMT + intervention vs intervention alone
Outcome: Quality of life: Physical Component Scale of SF36 and SF12 combined
1 month	MD 0.1, 95% CI -1.1 to 1.5	3	708	Moderate (inconsistency)
3 months	MD 0.3, 95% CI -0.7 to 1.3	2	619	Moderate (inconsistency)
6 months	MD -1.4, 95% CI -2.9 to 0.1	2	221	Low (inconsistency, imprecision)
12 months	MD -2.2, 95% CI -5.9 to 1.4	2	603	Moderate (inconsistency)
Outcome: Quality of life: Mental Component Scale of SF36 and SF12 combined
1 month	MD -0.2, 95% CI -1.6 to 1.2	3	708	Moderate (inconsistency)
3 months	MD 1.9, 95% CI -0.7 to 4.5	2	619	Moderate (inconsistency)
6 months	MD 1.8, 95% CI -0.1 to 3.7	2	221	Low (inconsistency, imprecision)
12 months	MD 1.0, 95% CI -0.3 to 2.2	2	605	Moderate (inconsistency)
Other outcomes not enough data
Comparison 5: Manipulation vs mobilization
All outcomes not enough data

Positive difference in effect indicates higher increased quality of health for SMT group compared to the control.

MD = mean difference.

OR = odds ratio.

a Recovery was classified as ‘recovered’ if the participant scored more than 50% improvement or were (much) better or had no symptoms. Medication use was classified for those using taking any using medication for LBP, while not taking any medication was classified as no medication use. Return to work was classified as participants had returned- to-work or if there were no sick days recorded. Satisfaction was classified as ‘satisfied with care’ if participants were (completely) satisfied or had scores >75%.