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Osteoarthritis - Evidence
ES (effect size)
Effect size is the mean change in an outcome measure divided by the standard deviation of the change.
- A positive effect size means that the intervention is more effective than the comparison.
- A negative effect size means that the intervention is less effective than the comparison.
- Interpretation of effect size is difficult because it is not clear what effect size is clinically meaningful — effect size is a dimensionless ratio. Effect size is used because it allows different outcome measures from different studies to be pooled for meta-analysis.
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