| Ordering Code | 113 |
|---|---|
| Test Name | Factor VIII Assay |
| Alias | Factor VIII, Functional Factor VIII Activity Coagulation Factor VIII Factor 8 |
| Preferred Specimen | Plasma |
| Preferred Container | Citrate, 3.2% (Lt Blue) |
| Other Specimen/Container | Whole Blood in Citrate, 3.2% (Lt Blue) if testing is done within 4 hours. |
| Optimum Volume | Plasma: 1.2 mL Whole Blood: Entire tube |
| Collection Instructions | Draw full tube Mix tube well. |
| Handling Instructions | Double centrifuge to produce platelet-poor plasma, avoid the WBC/platelet buffy layer, separate and freeze at -20 deg C immediately. Do NOT thaw once specimen is frozen. |
| Transport Requirements | Preferred method of transport is frozen plasma. |
| Specimen Stability | Ambient: 4 Hours Whole Blood Ambient: 4 Hours Plasma (Aliquoted) Frozen: 2 Weeks Plasma |
| Rejection Criteria | Clotted, Contaminated, Hemolyzed, Improperly filled or underfilled tube, Collected in the wrong anticoagulant, Mislabeled, Specimen older than stability limits |
| Avail. Stat | NO |
| Analytic Time | Up to 3 Days |
| Methodology | Clot Detection |
Reference range(s)
The reference ranges listed below are valid on this date of October 8, 2025.
| Component | Age | Male Norm | Male Critical Low | Male Critical High | Female Norm | Female Critical High | Female Critical Low | Units | Add'l info |
|---|---|---|---|---|---|---|---|---|---|
| Factor VIII Assay | ALL | 50-150 | 50-150 | % | This assay is... Note1 |
Note1:
This assay is a one-stage Factor VIII activity assay
This assay may not be suitable for monitoring all types of
Factor VIII clotting factor replacement therapy. Refer to drug manufacturer instructions for appropriate assay type for factor activity monitoring
.
