Magellan Medical Necessity Criteria Here you will find information regarding Magellan’s Medical Necessity Criteria (MNC). PDF Inpatient Hospitalization Click to download URL Outpatient Substance Abuse: ASAM/DMAS ARTS Manual Click to visit URL Psychiatric Residential Treatment Facilities: DMAS Residential Treatment Services Manual Click to visit URL Therapeutic Group Home: DMAS Residential Treatment Services Manual Click to visit The Adobe Reader is required to view PDF files.