therwise “go under the radar”. However, we found that lack of awareness of the model, time to implement its outputs and some concerns are barriers to usage for secondary school practitioners. Among primary and SEND school practitioners, low usage was mainly due to a perceived lack of relevance of the model, as well as constraints on time to embed the model in operational processes. For all risk models, we were unable to understand which variables the models use or how they were built, and as such could not perform a statistical assessment of their accuracy, as was our initial intention. The need for detailed documentation of how risk models are developed, the variables they use, as well as other aspects of the TFD build, are acknowledged as key recommendations for Bristol and other projects in this work area. Social Finance Limited +44 (0) 20 7770 6836 87 Vauxhall Walk, London SE11 5HJ socialfinance.org.uk 6 Our assessment of outcomes also included a cost-benefit analysis, which incorporated all development and maintenance costs, weighed against a calculation of time-saved as a monetised figure. This was calculated on an annualised basis and adjusted for inflation to give an overall financial total of benefits since the TFD’s inception. The contribution of the TFD to service users’ positive outcomes wasn’t included, due to the complexity of calculating this. Our analysis showed that for every £1 spent, the TFD has driven £1.30 of time-saved value. This should be seen as a proxy indicator of value rather than representative of bankable savings, and comes with a range of caveats, which are outlined in Section 5.5. Implementation In Section 6, we outline the findings from our process evaluation of how the TFD was developed and implemented, which offers valuable insight aro