Figure 2. Pain Relief on a 10-cm Visual Analog Scale Among Patients With Chronic Noncancer Pain Who Received Opioids vs Placebo in 42 High-Quality Randomized Clinical Trials.

The blue line represents the minimally important difference of 1 cm on the 10-cm visual analog scale for pain. The dashed vertical line represents the overall pooled measure of association.

^aWithin-group change from baseline data.

^bBetween-group differences in change from baseline data.

^cWeights are from random-effects analyses.

^dArticle reported results from 2 randomized clinical trials.

^eArticle only reported between-group mean difference and 95% CI.