“…The run-in or maintenance period used to identify drug responders typically involves titrating patients to a stable and tolerable dose that provides a mean improvement of 30 per cent or greater. About 30 per cent improvement has been proposed as the cutoff for a "clinically meaningful" response (Farrar et al, 2001;Younger et al, 2009), although this may vary from trial to trial (Farrar et al, 2001;Hewitt et al, 2011;Arthritis Research UK, 2013). So-called 'nonresponders' may include subjects who experience a lack of efficacy, fail to achieve a stabilized dose, or have too many or too serious adverse events, but patients may also be removed from the trial for protocol violation, withdrawal of consent, or other considerations (Hale et al, 2007;Katz et al, 2007;Hewitt et al, 2011).…”