The road to successful implementation of innovation in radiotherapy: A research-based implementation protocol

Background and purpose: Radiotherapy (RT) is rapidly advancing, yet only 50 % of innovations are implemented promptly. Despite the availability of Implementation Science (ImpSci) theories, models, and frameworks (TMFs), a theory–practice gap persists in effectively applying these insights in RT clinical practice. This study aims to develop a consensus-based implementation protocol for RT innovations using validated ImpSci knowledge. Material and methods: A literature review of TMFs (May–August 2023) and 20 semi-structured interviews with Dutch RT professionals (August–December 2023) identified key RT components for implementation. These insights informed a draft RT implementation protocol, which was refined through a three-round international Delphi study (March–September 2024) involving 11 RT and 5 ImpSci experts. Consensus was determined using a 5-point Likert scale, analysing medians, interquartile ranges (IQRs), and percentage scoring. Results: The Knowledge-to-Action (KTA) Framework and input from expert interviews were used to draft the protocol. Delphi response rates were 100 %, 93.8 %, and 88.9 % across rounds. In round 1, 88.9 % of elements achieved consensus (median = 4.0, IQR = 0.0–1.3); only the application of a prediction model for timely implementation (step 3c) needed revision after rounds 1 and 2. In round 3, also for step 3c consensus was reached (median = 4.0, IQR = 0.3). The protocol includes defining innovation types, stakeholder analysis, tailored implementation strategies, and a phased evaluation plan to ensure sustainability. Conclusion: This is the first consensus-based RT innovation implementation protocol, addressing the theory–practice gap with a structured clinical approach. Future research should validate the protocol and assess the impact of preparation on implementation success.