OSAC Validation
Definition
The framework for forensic assay validation published by the US Organisation of Scientific Area Committees, requiring demonstrations of sensitivity, specificity, mixture performance, and interference before a method is used operationally.
- Publishing body
- US Organisation of Scientific Area Committees
- Core requirements
- Sensitivity, specificity, mixture performance, interference testing
- Applies to
- Forensic assay methods before operational use
- Referenced in
- mRNA profiling for body fluid identification
Common questions
What happens if a lab skips full OSAC validation before using an assay?+
The method's results become vulnerable to a Daubert or Frye-style admissibility challenge, since opposing counsel can argue the assay's error rate and reliability were never independently demonstrated for casework conditions.
Does OSAC validation replace internal laboratory validation studies?+
No, it sets the minimum framework and criteria; each laboratory still runs its own internal validation study against that framework using its specific instruments, reagents, and staff before implementing the method.
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