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Oxford University Hospitals NHS Foundation Trust
Clinical Biochemistry

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Also known as: A4, ∆4

Specimen requirements

Sample type: Serum (Serum)

Collection requirements: No special requirements


Price on application

Turnaround time

Please see Turnaround times

Analytical method


Analysis undertaken at these site(s)

John Radcliffe Hospital

Reference intervals


< 10 years: 0.0 - 1.0 nmol/L
> 10 years: 3.0 - 8.0 nmol/L


< 10 years: 0.0 - 1.0 nmol/L
> 10 years: 3.0 - 8.0 nmol/L