OBJECTIVES: NICE has suggested that patient preference plays a role in physician selection of some Multiple Sclerosis (MS) treatments, but existing patient preference surveys are developed using literature rather than patient input.  Aims of this study were: combine existing literature with patient interviews to develop a discrete choice experiment (DCE) to assess patient preference for MS treatments and compare and contrast this information to critically appraise the mixed methods approach.  METHODS: A literature review was conducted to understand patient preference for attributes of existing MS treatments and inform development of a DCE. 12 one-to-one telephone interviews were conducted with MS patients. Interviews comprised two parts; understanding treatment attributes of importance to patients, and detailed cognitive appraisal of the DCE. Team-based framework analysis was conducted using interview audio files. RESULTS: Literature and patients interviewed generally agreed on key treatment attributes. Although brain lesions were identified from literature as a clinical marker, only one patient expressed this as important and others either did not understand it or the information was not shared by their clinician. In agreement with literature, patients shared that side effects impacting their quality of life were most important, for example fatigue and infection. Feedback on the DCE highlighted the importance of consistency between the wording length of the attribute level descriptions; patients considered longer descriptions correlated with a ‘worse’ level. Interviews also identified questions where language refinement was required to improve comprehensiveness. Patients had little knowledge of disease severity scores contrary to suggestions in the literature, but as disease severity was an important concept, this definition was changed.  CONCLUSIONS: Combining patient interviews and existing literature to develop a DCE can have advantages over using literature alone: greater confidence that attributes are important to patients, early refinement of language and an understanding of patients’ thought processes during DCE completion.