The definitions published from the QUERI Glossary in Implementation Science do not include a foundational definition for Intervention.
However, Rabin and colleagues define clinical intervention as:
The form in which an innovation is intended to be introduced into an organization. Interventions can include programs, practices, policies, technologies, and guidelines 
The QUERI Glossary defines Clinical Best Practice Intervention: 
The specific, evidence-based clinical/therapeutic practice or delivery system/organizational arrangement to be implemented to improve clinical outcomes, and for which current adherence and quality/ performance are inadequate.
Examples are a new drug, behavioral intervention or a new clinical role or delivery system arrangement such as case management or the chronic care model.
- Rabin BA, Brownson RC, Haire-Joshu D, Kreuter MW, Weaver NL: A glossary for dissemination and implementation research in health. J Public Health Manag Pract 2008, 14:117-123.
- Stetler, C., Mittman, B. S., & Francis, J. Overview of the VA Quality Enhancement Research Initiative (QUERI) and QUERI theme articles: QUERI Series. Implement Sci 2008, 3(1), 8.