It's good to feel better but it's better to feel good and even better to feel good as soon as possible for as long as possible. Response criteria and the importance of change at OMERACT 10.

The OMERACT patient reported outcomes (PRO) working group evaluated the methodologies for measuring responsiveness to change at the Outcome Measures in Rheumatology (OMERACT) 10 meeting. The outcome measures used in PRO studies are often expressed as continuous data at the group level (e.g., mean change in pain on a 0-100 visual analog scale). This is difficult to interpret and cannot easily be translated to the individual level of response. When interpreting scores at the individual level, it is important to take into account the following 4 main concepts: (1) improvement; (2) status of well-being; (3) onset of action; and (4) sustainability. Information from clinical trials on how many patients showed a response, what the level of response was, and how many patients are doing well, would be extremely useful for physicians. The objective of this article is to outline how continuous data may be reported in a clinically relevant manner. We will describe 5 techniques of reporting continuous variables in clinical studies and discuss the relevance of each.