Table 3.

GRADE assessment: supervised exercise compared to advice

Supervised exercise compared to advice for patients after surgery for lumbar disk herniation Patient or population: patients after surgery for lumbar disk herniation Setting: Hospital Intervention: supervised exercise Comparison: advice
Outcomes	№ of participants studies) Follow-up	Certainty of the evidence (GRADE)	Relative effect (95% CI)	Anticipated absolute effects
				Risk with advised	Risk difference with Supervised exercise
Pain follow up: mean 4 months	341 (5 RCTs)	⨁⨁◯◯◯ Very lowa,b,c	-	-	SMD 0.91 SD lower (1.61 lower to 0.21 lower)
Disability follow-up: mean 4 months	261 (4 RCTs)	⨁◯◯◯ Very lowb,c,d	-	-	SMD 0.8 SD lower (1.59 lower to 0.01 lower)

CI confidence interval, MD mean difference, SMD standardised mean difference

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.

^*The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

Explanations

^a2 studies at high risk and 2 studies with some concerns

^bhigh heterogeneity

^cn<400

^d2 studies at high risk, 1 study with some concerns