Long-term stability of relationships between reference materials for thromboplastins

Summary

Reference materials for thromboplastins are available from the World Health Organization (WHO) and the European Commission (EC). The long-term stability of the reference materials is an essential requirement and must be monitored. The relationship between two reference materials for rabbit thromboplastin, i. e. ERM-AD149 (EC) and RBT/90 (WHO), has been monitored in the period 1996–2002. No significant trend with time was detected. In addition,the relationship between ERM-AD149 and the reference material for bovine thromboplastin (i. e. OBT/79) has been determined in 1994 and in 2005 in multicentre studies (n = 11 and n = 9, respectively). No significant changes were observed in the relationships between these reference materials when all results were included (5% significance level).

Keywords

Thromboplastin - reference material - stability - calibration

• References

• 1 WHO Expert Committee on Biological Standardization. Guidelines for thromboplastins and plasma used to control oral anticoagulant therapy. WHO technical Report Series no. 889, 1999; 64-93.
• 2 Hermans J. et al. A collaborative calibration study of reference materials for thromboplastins. Thromb Haemost 1983; 50: 712-7.
• 3 European Commission, Community Bureau of Reference. The certification of the third reference material for rabbit thromboplastin CRM 149S. EUR 15958 EN. Office for Official Publications of the European Communities. Luxembourg. 1994
• 4 Van den Besselaar AMHP. Multi-center calibration of the third BCR reference material for thromboplastin, rabbit, plain, coded CRM 149S. Thromb Haemost 1995; 74: 1465-7.
• 5 ISO Guide 34 “General requirements for the competence of reference material producers”, ISO. Geneva: 2000
• 6 ICH Harmonised tripartite guideline, Q1A(R2): Stability Testing of New Drug Substances and Products (Second Revision). ICH, 6. 2. 2003
• 7 Van den Besselaar AMHP. Multi-center study of replacement of the international reference preparation for thromboplastin, rabbit, plain. Thromb Haemost 1993; 70: 794-9.
• 8 Tripodi A. et al. International collaborative study for the calibration of a proposed reference preparation for thromboplastin, human recombinant, plain. Thromb Haemost 1998; 79: 439-43.
• 9 Van den Besselaar AMHP. et al. Long-term stability of international reference preparations for thromboplastins. Br J Haematol 1988; 68: 321-8.
• 10 Poller L. et al. Long-term stability studies on the WHO IRP for thromboplastin (Human Plain BCT/253). Thromb Haemost 1994; 72: 682-4.
• 11 Van den Besselaar AMHP, Tripodi A. A reassessment of the relationship between international reference preparations for human and rabbit thromboplastins. Thromb Haemost 2002; 88: 459-61.
• 12 Poller L. et al. European Concerted Action on Anticoagulation. A multicentre calibration study of WHO international reference preparations for thromboplastin, rabbit (RBT/90) and human (rTF/95). J Clin Pathol 2005; 58: 667-9.
• 13 Quick AJ. Standardization of the one-stage prothrombin time. Thromb Diath Haemorrh 1972; 27: 179-80.
• 14 Stevenson KJ. et al. No deterioration after 13 years in a stability study of a rabbit brain, plain, thromboplastin, RBT 1010, in rubber-stoppered ampoules. Br J Haematol 2004; 125: 240-2.