Which data element is required in Form Locator 3a?

• A. Patient Control Number
• B. Medical Record Number
• C. Type of Bill
• D. Admission date

Answer: (A)

Form Locator 3a is the space for the Patient Control Number. This hospital-assigned identifier is used to uniquely mark this specific admission or encounter and travels with the claim to help line up the billing data with the correct clinical record across systems and payers. It’s tied to this particular visit and is distinct from the Medical Record Number, which identifies the patient within the hospital’s broader records. Type of Bill is determined in a different locator and describes the overall billing class of the claim (inpatient vs. outpatient), not the encounter identifier. Admission date belongs to the admission details captured in other locators. Because Form Locator 3a must carry a unique patient control number for each admission to ensure accurate tracking and matching of the claim, it is the correct element for this locator.