NASH is a potentially progressive form of NAFLD characterized by hepatocyte injury and liver inflammation which can cause fibrosis. Currently, there are limited data on the patient experience of NASH. Our aim was to use both literature review and patient interviews to understand the signs/symptoms and life impacts of NASH fibrosis stages F1-F4 that are important to patients, as well as begin to investigate the applicability of an instrument (ie, questionnaire) that may be used to capture patients' experiences. The literature review identified concepts (signs/symptoms and impacts) related to NASH fibrosis stages F1-F4 and the NASH-specific patient-reported outcome instrument (NASH-CHECK) for reporting patient experience of NASH. Interviews with 22 patients from Canada and the USA with NASH fibrosis stages F1-F4 revealed 27 signs/symptoms and 32 impacts that they felt were important, including fatigue, pain in the abdomen, worry, and frustration. Three concepts reported during patient interviews were not identified in the literature review. No concepts appeared to be exclusive to a specific fibrosis stage or presence/absence of obesity and no linear trends were identified between fibrosis stage or presence/absence of obesity and level of disturbance reported for concepts. The patient interviews supported the concepts included in the NASH-CHECK overall, demonstrating that it could be used to report the patient experience of NASH fibrosis stages F1-F4. Interviews with patients with NASH fibrosis stages F1-F4 revealed patients can self-report and elaborate on signs/symptoms and impacts related to the disease regardless of fibrosis stage. The NASH-CHECK was identified as a suitable instrument that could be used by patients with fibrosis stages F1-F4.