Code of Federal Regulations Title 45. Public Welfare § 45.1330.5 Stages of development

(a) Proof of concept means the stage of development where key technical challenges are resolved. Stage activities may include recruiting study participants, verifying product requirements;  implementing and testing (typically in controlled contexts) key concepts, components, or systems, and resolving technical challenges. A technology transfer plan is typically developed and transfer partner(s) identified;  and plan implementation may have started. Stage results establish that a product concept is feasible.

(b) Proof of product means the stage of development where a fully-integrated and working prototype, meeting critical technical requirements is created. Stage activities may include recruiting study participants, implementing and iteratively refining the prototype, testing the prototype in natural or less-controlled contexts, and verifying that all technical requirements are met. A technology transfer plan is typically ongoing in collaboration with the transfer partner(s). Stage results establish that a product embodiment is realizable.

(c) Proof of adoption means the stage of development where a product is substantially adopted by its target population and used for its intended purpose. Stage activities typically include completing product refinements;  and continued implementation of the technology transfer plan in collaboration with the transfer partner(s). Other activities include measuring users' awareness of the product, opinion of the product, decisions to adopt, use, and retain products;  and identifying barriers and facilitators impacting product adoption. Stage results establish that a product is beneficial.