Methotrexate is a commonly prescribed drug for patients diagnosed with rheumatoid arthritis (RA). Though it can positively impact disease activity, some patients experience side effects and intolerance. Salt et al. developed a scale to measure methotrexate intolerance for use in adult rheumatoid arthritis (RA) patients with an additional objective to describe its psychometric properties. This is the first known scale with favorable measurement properties to evaluate methotrexate intolerance using a patient-centered perspective.