Defining natural history: assessment of the ability of college students to aid in characterizing clinical progression of Niemann-Pick disease, type C.

Niemann-Pick Disease, type C (NPC) is a fatal, neurodegenerative, lysosomal storage disorder. It is a rare disease with broad phenotypic spectrum and variable age of onset. These issues make it difficult to develop a universally accepted clinical outcome measure to assess urgently needed therapies.