“…This study has the following limitations: (1) a sensitivity analysis was not performed on the model, (2) the cost savings model assumes that clinicians will change management of the patient when the patient does not respond to a medication within 6 months; however, retrospective data reveal that many inadequate responders to medications are kept on the same drug for longer periods of time, up to 18 months [ 52 ], (3) the model assumes that clinicians will prescribe with full adherence to the PrismRA test results, diverting patients who are not likely to respond to anti-TNF therapies to another MOA therapy, even though rheumatologists may be limited in doing so based on patient preference or payer formularies, and (4) the cost of PrismRA was not included in the model. Additionally, reported cost savings will depend on the price difference between the anti-TNF therapies and alternative MOA therapies used, which will differ based on formulary policies and use of biosimilars [ 53 – 55 ].…”