The amount of a ectonucleoside triphosphate diphosphohydrolase 3 (human) when measured in cerebrospinal fluid. The trait is level of ectonucleoside triphosphate diphosphohydrolase 3 (human) in cerebrospinal fluid (Ontology of Biological Attributes id OBA_2056342). Also known as: cerebrospinal fluid ectonucleoside triphosphate diphosphohydrolase 3 (human) amount.