Towards principled adequacy for purpose in choosing evaluation methods

Abandoning gold-standard approaches to evaluation methodology renews the challenge of methodological choice and justification. We address this challenge by developing a novel account of methodological assessment we term ‘Principled Adequacy for Purpose’. We develop this account by considering recent work centring both the role of questions and values for methodological choice. While we argue that both approaches make important improvements over traditional evidence hierarchies, these frameworks by themselves also face significant limitations. We consider that combining these frameworks, while giving greater consideration to the notion of evaluative purpose, affords better guidance for methodological decision-making in evaluation. For this, we in particularly draw on recent work on Adequacy for Purpose in model evaluation, before combining these approaches under the ‘Principled Adequacy for Purpose’ umbrella.