In which CPT Appendix would all modifiers be found?

The correct answer is Appendix A, as this appendix is specifically dedicated to listing and providing descriptions for all modifiers that can be used in conjunction with CPT codes. Modifiers are important in coding as they provide additional information about the service performed, indicating that the procedure has been altered in some way but not changed in its definition or code.

Appendix A organizes all the modifiers systematically, making it easy for coders to reference them when needed. This helps ensure accurate coding and billing for procedures, as modifiers can affect reimbursement and procedural reporting.

The other appendices serve different purposes. For instance, Appendix B is typically used for listing changes or revisions to the CPT codes, Appendix C may include supplementary information related to codes, and Appendix D provides a summary of the performance measures. Each appendix has a distinct function, but it is Appendix A that focuses solely on modifiers.