Evaluating the testing and treatment scale-up should include the assessment of both processes and outcomes.

Process evaluations assess what was implemented and how well it was implemented, whereas outcome evaluations examine whether a program has the intended effects for the target population. The evaluation for the SToP-C study included qualitative and quantitative assessments of the processes and outcomes, as well as mathematical modelling of the epidemiological impact, cost-effectiveness and budget impact of prisons-based DAA treatment scale-up within the prisons and on the wider community.