Final answer:
A peripheral blood smear collected by a phlebotomist is typically used for a WBC differential test, which helps diagnose conditions related to white blood cells.
Step-by-step explanation:
The collection technique of a peripheral blood smear by a phlebotomist is typically used for a WBC differential test. This involves creating a smear of blood on a slide, which is then stained with a special dye and examined under a microscope to differentiate and count the types of white blood cells. Information from this test can be vital for diagnosing a variety of conditions, including infections, anemia, and blood disorders. Performing a peripheral blood smear is not typically associated with erythrocyte sedimentation rate (ESR) testing, blood cultures, or arterial blood gas analysis.