Multiple sclerosis and fatigue: understanding the patient's needs.

Fatigue is among the most common and debilitating symptoms of multiple sclerosis (MS), affecting approximately 80% of persons who have the disease. Recently, as part of the National Institutes of Health Patient Reported Outcome Measurement Information System (PROMIS), a bank of items was developed for measuring self-reported fatigue. This article has two purposes. (1) To assess, from the perspective of individuals living with MS, the relevance of a subset of items from the PROMIS fatigue item bank. (2) To identify additional aspects of fatigue that individuals with MS believe are important for clinicians when asking about their fatigue experience.