Which type of codes are designated with the 1 symbol and are found in Appendix D of the CPT code book?

The correct response identifies add-on codes, which are designated with the + symbol in the Current Procedural Terminology (CPT) code book and can be found in Appendix D. Add-on codes are used to report additional procedures that are typically performed alongside a primary procedure. These codes cannot stand alone; they must be billed in conjunction with their associated primary codes.

Understanding the structure of CPT codes helps medical administrative assistants accurately code procedures and services. The inclusion of add-on codes in Appendix D highlights their specific guidelines and usage in billing processes, ensuring proper reimbursement and compliance in medical coding practices. Add-on codes enhance the specificity of the coding system by providing a means to capture the full scope of care provided, especially when multiple related services are delivered during a single patient encounter.

Therefore, the answer highlights the crucial role add-on codes play in accurately reflecting the complexity and extent of a patient's treatment in the healthcare system.