Which block on the CMS-1500 claim form indicates a workers' compensation claim?

The correct block that indicates a workers' compensation claim on the CMS-1500 claim form is block 10a. This block is specifically designated for indicating the other insurance information, and more importantly, it includes the designation for whether the care was for a work-related injury.

When a patient is receiving treatment as a result of a workers' compensation claim, it is crucial for the billing and coding staff to identify this on the claim to ensure the appropriate payer is billed. Block 10a provides the necessary information that delineates workers' compensation as the primary source of payment, ensuring that the claim is processed correctly according to workers' compensation regulations.

The other blocks mentioned, such as Block 10 and Block 12, do not have the specific indication for workers' compensation. Block 10 is used for the other insurance policy number, and Block 12 is to indicate the insured's or patient's date of birth. Block 13 is reserved for the patient's signature or the signature of their representative and doesn’t pertain to workers' compensation claims either.