Fig 3.

Cumulative pooled analysis for knee pain based on large, placebo controlled trials (n=24 trials, 8997 patients randomised). The shaded areas represent the areas of clinical equivalence (darker areas represent the minimal clinically important difference of 0.37, lighter areas represent the more stringent 0.2 margin of equivalence). Results are for random effects model. Over the years, between trial variance estimates (τ²) varied between 0 and 0.02, suggesting low heterogeneity. P values for equivalence are based on two one sided tests. The number of participants analysed might be smaller than the number of randomised participants