Vitamin A relative dose response
(RDR)

Sample type: -

Serum.

Uses: -

Estimation of total body stores of vitamin A.

Precautions: -

Test is done after 5 hours from intravenous injection of 1000 micrograms of retinyl palmitate.

Interfered factors: -

Vitamin A concentration is greater than 20 micrograms/g

Pre-analytical errors: -

• Misidentification of patient’s sample.

• Unproper storage of sample.

Corrective actions: -

• Correct labelling of the sample.

• Proper storage for the specimens.

Post-analytical errors: -

• Delay time in delivery.

• Miscalculations in the results.

Corrective actions: -

• Delivering the results on time.

• Correct labelling of samples.

Reference range: -

• Children age <16 (0.66-2.65 μmol/L).

• Adults age >16 (1.40-3.84 μmol/L).