title: Introduction. Special Issue Overview: Optimizing Mixed Methods for Implementation Research in Large Systems.
authors.affiliation: New York University Langone Medical Center, New York, NY, USA, Kimberly.Hoagwood@nyumc.org.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Hoagwood
authors.forename: Serene
authors.initials: S
authors.lastname: Olin
authors.forename: Sarah
authors.initials: S
authors.lastname: Horwitz
mesh_terms: D003695:Delivery of Health Care; D004059:Diffusion of Innovation; D055317:Evidence-Based Practice; D006302:Health Services Research; D006801:Humans; D012107:Research Design