Abstract
BACKGROUND: With innovation in service delivery increasingly viewed as crucial to the long-term sustainability of health systems, NHS England launched an ambitious new model of care (Vanguard) programme in 2015. Supported by a £350 million transformation fund, 50 Vanguard sites were to act as pilots for innovation in service delivery, to move quickly to change the way that services were delivered, breaking down barriers between sectors and improving the coordination and delivery of care. METHODS: As part of a national evaluation of the Vanguard programme, we conducted an evidence synthesis to assess the nature and quality of locally commissioned evaluations. With access to a secure, online hub used by the Vanguard and other integrated care initiatives, two researchers retrieved any documents from a locally commissioned evaluation for inclusion. All identified documents were downloaded and logged, and details of the evaluators, questions, methodological approaches and limitations in design and/or reporting were extracted. As included evaluations varied in nature and type, a narrative synthesis was undertaken. RESULTS: We identified a total of 115 separate reports relating to the locally commissioned evaluations. Five prominent issues relating to evaluation conduct were identified across included reports: use of logic models, number and type of evaluation questions posed, data sharing and information governance, methodological challenges and evaluation reporting in general. A combination of resource, data and time constraints means that evaluations often attempted to but did not fully address the wide range of questions posed by individual Vanguards. CONCLUSIONS: Significant investment was made in independent local evaluations of the Vanguard programme by NHS England. This synthesis represents the only comprehensive attempt to capture methodological learning and may serve as a key resource for researchers and policy-makers seeking to understand investigating large-scale system change, both within the NHS and internationally. PROSPERO (Registration number: CRD42017069282).