Two survey exercises are distributed each financial year. Each survey includes a minimum of one sample for Factor XIII assay - participants are invited to perform their routine FXIII assays, to reflect their clinical practice.
All samples are of lyophilised plasma, from donors screened for hepatitis B surface antigen (HBsAg) and for antibodies to hepatitis C virus and human immunodeficiency virus types 1 and 2 (anti HIV-1+2).
Individual survey reports for each survey are made available within two weeks of the closing date for the respective survey. Reports are made available as paper copies, and email alerts are sent out about availability.