Mapping review of 'proof-of-concept' in mental health implementation research using the TRL framework: a need for a better focus and conceptual clarification.

The TRL was a useful reference framework to improve terminological clarity around the term 'proof-of-concept' in implementation research. To extend the use of TRL in implementation sciences, this framework has now been adapted and validated to a health and social science-related research context accompanied by a health-related glossary of research process terms and definitions to promote a common vocabulary and shared understanding in implementation sciences.