Commonwealth of Massachusetts MassHealth Provider Manual Series Subchapter Number and Title Table of Contents Page vi Mental Health Center Manual Transmittal Letter MHC-43 Date 04/15/11 6. Service Codes and Descriptions Service Codes and Descriptions 6-1 Appendix A. Directory A-1 Appendix B. Enrollment Centers B-1 Appendix C. Third-Party-Liability Codes C-1 Appendix D. Supplemental Instructions for TPL Exceptions D-1 Appendix W. EPSDT Services Medical and Dental Protocols and Periodicity Schedules W-1 Appendix X. Family Assistance Copayment and Deductibles X-1 Appendix Y. EVS Codes/Messages Y-1 Appendix Z. EPSDT/PPHSD Screening Services Codes Z-1