The "efficacy-effectiveness gap" refers to the difference between the treatment efficacy as measured by randomized controlled trials (RCTs) and treatment effectiveness as measured in "real world" clinical settings. Prior studies have documented the existance of this gap in a variety of clinical contexts and attributed its existence to a number of factors, including overly restrictive subject inclusion/exclusion criteria in RCTs and differences in treatment efficacy ascertainment.In this protocol and statistical analysis plan, we document a protocol for a forthcoming study relevant to assessing the efficacy-effectiveness gap of the medication Tofacitinib as used to treat Ulcerative Colitis. Specifically, we detail the following:1) What covariates are needed to compare the real-world effectiveness of Tofacitinib with its efficacy as measured by pivotal clinical trials2) What approach we propose to extract these covariates from the electronic health records at our institution in a relatively reproducible fashion, balancing accuracy with practicality.3) How we propose to analyze the data