Gron KL, et al. - Authors studied 8987 treatment courses thoroughly to analyze the relative risks (RR) of serious infections (SI) in cases with rheumatoid arthritis (RA) initiating treatment with abatacept, rituximab or tocilizumab in routine care and also to estimate the crude and age-and gender-adjusted incidence rates (IRs) of SI in Denmark and Sweden. They observed 456 and 639 SI events during 0–12 and 0–24 months of follow-up. They also noticed the age- and gender-adjusted 12-month IRs for abatacept/rituximab/tocilizumab: 7.1/8.1/6.1 for Denmark and 6.0/6.4/4.7 for Sweden. They observed variations in IR of SI among the drugs with diverse RRs ie, tocilizumab < abatacept < rituximab. They also suggested becoming cautious due to few events and risk of residual confounding.