title: Carrier detection in hemophilia A: a cooperative international study. II. The efficacy of a universal discriminant.
abstract: Factor VIII (F.VIII) and von Willebrand factor (VWF):Ag data collected by eight laboratories on a total of 336 obligatory carriers of hemophilia A and 137 normal women were used to answer several questions concerning the construction of linear discriminants for carrier detection. It was found: that a "universal" linear discriminant can be constructed which is suitable for use in all laboratories and is nearly as effective as laboratory-specific discriminants; that inclusion of age and ABO blood type data improved the efficacy of these discriminants; that substitution of alternative assays for F.VIII and VWF:Ag did not generally improve the efficacy of the discriminants over that obtained using the bioassay for F.VIII:C and Laurell's immunoassay for VWF:Ag; that linear discriminants were far more effective than discriminants based on the F.VIII:C/VWF:Ag ratio. A step-wise procedure is given which any laboratory may follow in using the universal discriminant for carrier detection.
mesh_terms: D000017:ABO Blood-Group System; D000328:Adult; D000941:Antigens / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005169:Factor VIII / Q000032:analysis; D005260:Female; D006580:Genetic Carrier Screening / Q000379:methods*; D006467:Hemophilia A / Q000235:genetics*; D006801:Humans; D007124:Immunoenzyme Techniques; D007391:International Cooperation; D010641:Phenotype; D014841:von Willebrand Factor / Q000032:analysis
chemical_list: D000017:ABO Blood-Group System; D000941:Antigens; C029417:Von Willebrand antigen; D014841:von Willebrand Factor; D005169:Factor VIII