Clinical observations and their relationship to laboratory findings in the haemophilias.

Continuous observations in shcool terms have been made on the frequency of spontaneous bleeding episodes in a group of adolescent boys suffereing from haemophilia (39 cases), Christmas disease (9 cases), and von Willebrand's disease (2 cases). The observations suggest that in haemophilia other factors, besides the deficient factor VIII, affect the bleeding frequency. In the two boys with von Willebrand's disease, the lower level of factor VIII was associated with the milder symptoms; whereas in boys with Christmas disease clinical severity and laboratory results seemed to be correlated.