K. L. Hyrich, M. Lunt, K. D. Watson, and D. P. Symmons, Silman AJBritish Society for Rheumatology Biologics Register. Outcomes after switching from one anti-tumor necrosis factor alpha agent to a second anti-tumor necrosis factor alpha agent in patients with rheumatoid arthritis: results from a large UK national cohort study, Arthritis Rheum, vol.56, pp.13-20, 2007.

S. B. Cohen, P. Emery, and M. W. Greenwald, Rituximab for rheumatoid arthritis refractory to anti-tumor necrosis factor therapy: Results of a multicenter, randomized, double-blind, placebo-controlled, phase III trial evaluating primary efficacy and safety at twenty-four weeks, Arthritis Rheum, vol.54, pp.2793-806, 2006.

P. Emery, E. Keystone, and H. P. Tony, IL-6 receptor inhibition with tocilizumab improves treatment outcomes in patients with rheumatoid arthritis refractory to anti-tumour necrosis factor biologicals: results from a 24-week multicentre randomised placebocontrolled trial, Ann Rheum Dis, vol.67, pp.1516-1539, 2008.

M. C. Genovese, J. C. Becker, and M. Schiff, Abatacept for rheumatoid arthritis refractory to tumor necrosis factor alpha inhibition, N Engl J Med, vol.353, pp.1114-1137, 2005.

C. Salliot, A. Finckh, and W. Katchamart, Indirect comparisons of the efficacy of biological antirheumatic agents in rheumatoid arthritis in patients with an inadequate response to conventional disease-modifying antirheumatic drugs or to an anti-tumour necrosis factor agent: a meta-analysis, Ann Rheum Dis, vol.70, pp.266-71, 2011.

M. Schoels, D. Aletaha, J. S. Smolen, and J. B. Wong, Comparative effectiveness and safety of biological treatment options after tumour necrosis factor ? inhibitor failure in rheumatoid arthritis: systematic review and indirect pairwise meta-analysis, Ann Rheum Dis, vol.71, pp.1303-1311, 2012.

G. J. Bergman, M. C. Hochberg, M. Boers, N. Wintfeld, A. Kielhorn et al., Indirect comparison of tocilizumab and other biologic agents in patients with rheumatoid arthritis and inadequate response to disease-modifying antirheumatic drugs, Semin Arthritis Rheum, vol.39, pp.425-466, 2010.

M. L. Hetland, I. J. Christensen, and U. Tarp, Direct comparison of treatment responses, remission rates, and drug adherence in patients with rheumatoid arthritis treated with adalimumab, etanercept, or infliximab: results from eight years of surveillance of clinical practice in the nationwide Danish DANBIO registry, Arthritis Rheum, vol.62, pp.22-32, 2010.

X. Mariette, J. E. Gottenberg, P. Ravaud, and B. Combe, Registries in rheumatoid arthritis and autoimmune diseases: data from the French registries, Rheumatology (Oxford), vol.50, pp.222-231, 2011.

M. A. Hernán and J. M. Robins, Using Big Data to Emulate a Target Trial When a Randomized Trial Is Not Available, Am J Epidemiol, vol.183, pp.758-64, 2016.

P. R. Rosenbaum, Model-based direct adjustment, J Am Stat Assoc, vol.82, pp.387-94, 1987.

J. M. Robins, M. A. Hernán, and B. Brumback, Marginal structural models and causal inference in epidemiology, Epidemiology, vol.11, pp.550-60, 2000.

P. C. Austin and E. A. Stuart, Moving towards best practice when using inverse probability of treatment weighting (IPTW) using the propensity score to estimate causal treatment effects in observational studies, Stat Med, vol.34, pp.3661-79, 2015.

P. M. Grambsch and T. M. Therneau, Proportional hazards tests and diagnostics based on weighted residuals, Biometrika, vol.81, pp.515-541, 1994.

P. Royston and M. K. Parmar, The use of restricted mean survival time to estimate the treatment effect in randomized clinical trials when the proportional hazards assumption is in doubt, Stat Med, vol.30, pp.2409-2430, 2011.

H. M. Dehbi, P. Royston, and A. Hackshaw, Life expectancy difference and life expectancy ratio: two measures of treatment effects in randomised trials with non-proportional hazards, BMJ, vol.357, p.2250, 2017.

T. Pascart, P. Philippe, and E. Drumez, Comparative efficacy of tocilizumab, abatacept and rituximab after non-TNF inhibitor failure: results from a multicentre study, Int J Rheum Dis, vol.19, pp.1093-102, 2016.

H. C. Leffers, M. Ostergaard, and B. Glintborg, all departments of rheumatology in Denmark. Efficacy of abatacept and tocilizumab in patients with rheumatoid arthritis treated in clinical practice: results from the nationwide Danish DANBIO registry, Ann Rheum Dis, vol.70, pp.1216-1238, 2011.

S. Das, E. M. Vital, and S. Horton, Abatacept or tocilizumab after rituximab in rheumatoid arthritis? An exploratory study suggests non-response to rituximab is associated with persistently high IL-6 and better clinical response to IL-6 blocking therapy, Ann Rheum Dis, vol.73, pp.909-921, 2014.

U. A. Walker, V. K. Jaeger, and K. Chatzidionysiou, Rituximab done: what's next in rheumatoid arthritis? A European observational longitudinal study assessing the effectiveness of biologics after rituximab treatment in rheumatoid arthritis, See rights and reprints, vol.55, pp.230-236, 2016.

L. R. Harrold, G. W. Reed, and D. H. Solomon, Comparative effectiveness of abatacept versus tocilizumab in rheumatoid arthritis patients with prior TNFi exposure in the US Corrona registry, Arthritis Res Ther, vol.18, p.280, 2016.

J. E. Gottenberg, D. S. Courvoisier, and M. V. Hernandez, Brief Report: Association of Rheumatoid Factor and Anti-Citrullinated Protein Antibody Positivity With Better Effectiveness of Abatacept: Results From the Pan-European Registry Analysis, Arthritis Rheumatol, vol.68, pp.1346-52, 2016.

C. Gabay, P. Emery, and R. Van-vollenhoven, ADACTA Study Investigators. Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial, Lancet, vol.381, issue.13, pp.60250-60250, 2013.

M. Schiff, M. E. Weinblatt, and R. Valente, Head-to-head comparison of subcutaneous abatacept versus adalimumab for rheumatoid arthritis: two-year efficacy and safety findings from AMPLE trial, Ann Rheum Dis, vol.73, pp.86-94, 2014.

M. A. Hernán and . The-c-word, Scientific Euphemisms Do Not Improve Causal Inference From Observational Data, Am J Public Health, vol.108, pp.616-625, 2018.

J. E. Gottenberg, P. Ravaud, and A. Cantagrel, Positivity for anticyclic citrullinated peptide is associated with a better response to abatacept: data from the 'Orencia and Rheumatoid Arthritis' registry, Ann Rheum Dis, vol.71, pp.1815-1824, 2012.

J. E. Gottenberg, P. Ravaud, and T. Bardin, AutoImmunity and Rituximab registry and French Society of Rheumatology. Risk factors for severe infections in patients with rheumatoid arthritis treated with rituximab in the autoimmunity and rituximab registry, Arthritis Rheum, vol.62, pp.2625-2657, 2010.