Summary of findings 1. Exercise therapy compared to sham/placebo treatment for acute non‐specific low back pain.

Exercise therapy compared to sham treatment for acute non‐specific LBP
Patient or population: acute non‐specific LBP Setting: primary or secondary care Intervention: exercise therapy Comparison: sham/placebo treatment
Outcomes	Anticipated absolute effects (95% CI)		Relative effect (95% CI)	No. of participants (studies)	Certainty of the evidence (GRADE)	Comments
	Assumed risk (sham treatment)	Corresponding risk (exercise therapy)
Pain Assessed with VAS (0–100, higher is worse) Follow‐up: short term	The mean pain score was 20.9 (SD 23).a	The mean pain score in the intervention group was 0.80 lower (5.79 lower to 4.19 higher).	MD −0.80 (−5.79 to 4.19)	299 (1 RCT)	⊕⊕⊝⊝ Verylowb	The difference did not meet the predefined criterion for clinically relevant change. The evidence is very uncertain about the effect of exercise therapy on pain compared to sham treatment. Absolute difference: 1% less pain (95% CI 4% more to 6% less) in the exercise group.a Relative difference: 4% less pain (95% CI 20% less to 28% more) in the exercise group.a
Functional status Assessed with Nottingham Health Profile Questionnaire (0–100, higher is worse) Follow‐up: short term	The mean functional status score was 13.3 (SD 18).a	The mean functional status score in the intervention group was 2.00 higher (2.20 lower to 6.20 higher).	MD 2.00 (−2.20 to 6.20)	299 (1 RCT)	⊕⊕⊝⊝ Verylowb	The difference did not meet the predefined criterion for clinically relevant change. The evidence is very uncertain about the effect of exercise therapy on functional status compared to sham treatment. Absolute difference: 2% worse functional status (95% CI 2% better to 6% worse) in the exercise group.a Relative difference: 15% worse functional status (95% CI 17% better to 47% worse) in the exercise group.a
Perceived recovery	—		—	—	—	No studies reported whether participants recovered.
Adverse events	—		—	—	—	No studies reported whether any adverse events occurred.
CI: confidence interval; LBP: low back pain; MD: mean difference; SD: standard deviation; VAS: visual analogue scale.
GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate; the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited; the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate; the true effect is likely to be substantially different from the estimate of effect.

^a The mean scores, mean differences, absolute differences, and the relative percentage changes are based on data from one study (Faas 1993).
^b Downgraded one level for risk of bias and two levels for imprecision (only one study with fewer than 400 participants).