The amount of a pro-neuregulin-3, membrane-bound isoform (human) when measured in cerebrospinal fluid. The trait is level of pro-neuregulin-3, membrane-bound isoform (human) in cerebrospinal fluid (Ontology of Biological Attributes term OBA_2058205). Also known as: cerebrospinal fluid pro-neuregulin-3, membrane-bound isoform (human) amount.