Predicted number of joint bleeds according to factor activity level and age group for patients with hemophilia A or B based on a regression model. Predicted number of joint bleeds according to factor activity level and age group for patients with hemophilia A or B based on a regression model. Comparison of predicted number of joint bleeds per 6-month period according to FA level for a hypothetical white patient with commercial insurance, normal BMI, and HIV negativity with either hemophilia A (dashed line) or hemophilia B (solid line). J. Michael Soucie et al. Blood Adv 2018;2:2136-2144 ©2018 by American Society of Hematology