What must be checked in Box 1 of the CMS-1500 before submission?

Box 1 of the CMS-1500 form is designated for indicating whether the patient has insurance coverage. This box is crucial because it directly impacts the claims processing; the health insurance company needs to confirm the patient's coverage before proceeding with any payments for services rendered. Ensuring that this box is checked and accurately reflects the patient's insurance status allows the claims to be processed efficiently. Other elements such as procedure codes, the doctor's signature, and place of service are important for the overall claim but are not the focus of Box 1. This box serves as the first step in determining if the claim can be accepted based on the patient's insurance eligibility, making it essential to verify.