There was a gradual increase in number of new-starts per year, from 161 in 2006 to 278 in 2015 (p value 0.0036), but there were no statistically significant calendar trends in age, disease duration, BASDAI (Bath Ankylosing Spondylitis Disease Activity Index) or ASDAS at start of the first TNFi, although there was a significant trend for decreasing CRP over time, as described in detail in Additional file 1. The gene discussed is CRP; the disease is ankylosing spondylitis.