Fig. 2From: Factors associated with ASDAS remission in a long-term study of ankylosing spondylitis patients under tumor necrosis factor inhibitorsRetention to therapy (Kaplan-Meier analysis); log-rank test: non-switchers vs switchers - second anti-TNF (P = 0.007) and non-switchers vs switchers - third anti-TNF (P = 0.02)Back to article page