Regression to the mean using the disease activity score in eligibility and response criteria for prescribing TNF- inhibitors in adults with rheumatoid arthritis

Abstract

Objectives. When patients with rheumatoid arthritis (RA) are selected to start TNF-α inhibitors on the basis of high disease activity scores (DAS), some of the fall in DAS will be due to regression to the mean (RTM). We have assessed the extent to which such RTM explains DAS improvements on TNF-α inhibitors in routine clinical practice.