title: Who is serving drug abuse clients: treatment delivery by professionals versus paraprofessionals, by paid staff versus volunteers.
mesh_terms: D000488:Allied Health Personnel; D001291:Attitude of Health Personnel; D003131:Combined Modality Therapy; D003376:Counseling; D005500:Follow-Up Studies; D006801:Humans; D008691:Methadone / Q000627:therapeutic use; D011369:Professional-Patient Relations; D012718:Set, Psychology; D019966:Substance-Related Disorders / Q000523:psychology / Q000628:therapy*; D014838:Volunteers; D000078329:Workforce
chemical_list: D008691:Methadone