Proposals and evaluation of different thresholds for defining a clinically meaningful improvement in a relative change in the rheumatoid arthritis impact of disease (RAID) score. a. Proposals of threshold according to different techniques and different times of evaluation. b. Evaluation of external validity (versus DAS28-ESR) of different proposed thresholds. c. Evaluation of external validity (versus patient's global assessment) of different proposed thresholds. * Thresholds, proposal based on the following technique and time of calculation: a, 75th percentile technique at week 4; b, ROC technique at week 4; c, empirical technique; d, correct classification at week 4 and 75th percentile at week 12; e, 75th percentile at week 12; f, ROC technique at week 12; g, correct classification at week 12; h, empirical technique. +Positive likelihood ratio (higher values are indicative of better performing thresholds. See Methods for further information). DAS28-ESR, Disease Activity Score 28-erythrocyte sedimentation rate; ROC, receiver operating characteristic.