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Osteoarthritis - Evidence
WMD (weighted mean difference)
The weighted mean difference is used in meta-analysis to combine results from a number of different studies, while giving more weight to studies that give us more information.
- A number of methods are used to calculate the weighted mean difference. The simplest method uses the number of participants. More complex methods also take into account the number of events, for example by using the variance to give more weight to more precise results.
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