Final answer:
A finger stick, or capillary blood test, should not be performed on patients who are less than one year old due to the risk of tissue damage and infection.
Step-by-step explanation:
A finger stick should never be performed on a patient less than one year old. This procedure, also known as a capillary blood test, is typically unsuitable for infants due to their skin's characteristics and the potential for tissue damage. Additionally, infants have a higher risk of infection and may not have enough blood volume to safely provide a sample without causing harm.