This article provides evidence from the OMERACT (Outcome Measures in RheumAtology Clinical Trials) consensus conferences on patient-reported pain as a key outcome measure for most rheumatologic diseases, including rheumatoid arthritis, osteoarthritis, osteoporosis, back disorders, ankylosing spondylitis, and lupus. These core sets have been endorsed internationally by the World Health Organization, the International League Against Rheumatism, the US National Osteoporosis Foundation, and the OsteoArthritis Research Society International (OARSI). Future research will assess methods for improving interpretability of pain outcomes for patients and clinicians. These methods include determining minimal clinically important differences and number needed to treat (NNT) for continuous outcomes such as pain.
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