J Can Chiropr Assoc 2026 (Apr); 70 (1): 27-54

Appendix 6. Certainty of evidence for intervention --
Efficacy of SMT vs comparator for Low back pain

Outcomes No. of participants randomized (Studies) Results favor (SMT, null, comparator) Risk of Bias (low, acceptable, high) Certainty of the evidence Comments (Reasons for downgrade/ upgrade)
Pain Intensity
Scale: VAS, 11-Point Scale, 21-Point box scale		 495(3 RCT) 3 favor null 2 low risk, 1 acceptable risk ⊕⊕○○
Low		 Imprecision
Back-Specific Disability Status
Scale: ODI, MRS		 377 (2 RCT) 1 favors SMT
1 favors null		 2 low risk ⊕⊕○○
Low		 Imprecision
Functional Status
Scale: SF-36 physical function subscale		 377(2 RCT) 2 favors null 2 low risk ⊕⊕○○
Low		 Imprecision
Quality of Life/ Activities of daily living No trials were identified that reported on this outcome. ⊕○○○
Very Low		 No Relevant Studies

Abbreviations:

RCT = randomized controlled trial;
SF = short form;
SMT = spinal manipulative therapy,
VAS = verbal/visual pain scale,
ODI = Oswestry Disability Index,
MRS = Modified Roland Scale