Full blood count, examination of blood film, measurement of mean platelet volume |
Tests of liver and renal function |
Prothrombin time |
Activated partial thromboplastin time |
Thrombin time and Clauss fibrinogen concentration |
Factor VIII and factor IX assays* |
von Willebrand factor antigen, ristocetin cofactor and blood group* |
Factor XIII assay, platelet membrane glycoproteins (in certain situations – see text)* Platelet function analyser-100 (if available)* |
↵* Not included in initial investigations suggested in the Royal College of Paediatrics and Child Health Child Protection Companion.16