RT Journal Article SR Electronic T1 Laboratory Monitoring of Factor VIII and Factor IX in Hemophilia Patients JF American Society for Clinical Laboratory Science JO Clin Lab Sci FD American Society of Chemistry and Laboratory Science SP 27 OP 35 DO 10.29074/ascls.2018001305 VO 32 IS 1 A1 Nardi, Michael A. YR 2019 UL http://hwmaint.clsjournal.ascls.org/content/32/1/27.abstract AB This review describes and discusses the different types of factor assays used in the clinical laboratory for the diagnosis, as well as during therapeutic management, of hemophilia patients. After diagnosis, infusion of factor replacement concentrates is the standard of treatment for patients with hemophilia to prevent or treat bleeding episodes. Monitoring of the factor activity is necessary to assure proper treatment. Several assays are used to assess the factor activity at the time of diagnosis and during therapeutic management. The pros and cons of each assay are discussed in detail. With the introduction of many new replacement products, it is important the clinical laboratory understands the advantages and disadvantages of each assay with respect to each of the replacement products available.