Forty-seven studies with 5,391 participants were included in the review.
Acute low-back pain:
There was no significant difference in short- or long-term pain relief or function when exercise was compared to treatment/placebo/sham (four studies: two high quality and two low quality; studies had significant heterogeneity).
No significant benefit of spinal manipulation for pain relief was observed in the short-term (three studies: one medium and two low quality; studies had no significant heterogeneity.
There was a significant increase in pain relief with NSAIDs in the short term (three studies: one high quality and two moderate quality; SMD 0.51, 95% CI: 0.16 to 0.86; significant heterogeneity between the studies).
There was a significant increase in short-term pain relief with non-benzodiazepines (four studies: two high quality and two moderate quality; SMD 0.52, 95% CI: 0.42 to 0.65; no significant heterogeneity between the studies, I2=0%).
Chronic low-back pain:
There was no significant difference in short- or long-term pain relief or function when exercise therapy was compared to treatment/placebo/sham (six studies: one medium quality and five low quality; significant heterogeneity between the studies).
There was a significant benefit in pain relief in the short term with behaviour therapy (seven studies: one high quality, four medium quality, and two low quality; SMD 0.57, 95% CI: 0.33 to 0.81, I2=0%), but not for function.
There was no significant pain relief with spinal manipulation in the short-term (five studies: four medium quality and one low quality; significant heterogeneity between the studies).
There was no significant pain relief with Transcutaneous Electrical Nerve Stimulation (TENS) in the short term (two studies: one high quality and one medium quality; no heterogeneity).
There was a significant increase in pain relief with acupuncture in the short term (seven studies: three high quality, three moderate quality and one low quality; SMD 0.61, 95% CI: 0.41 to 0.81, I2=0%).
There were also significant positive effects on pain relief in the short-term of benzodiazepines (three studies of medium quality; RR 0.82, 95% CI: 0.72, 0.94, I2=0%) and NSAIDs (three studies; RR 0.61, 95% CI: 0.50 to 0.74).