Macro- and Micro-Validation: Beyond the ‘Five Sources’ Framework for Classifying Validation Evidence and Analysis

Abstract

This paper argues that the dominant framework for conceptualizing validation evidence and analysis "“ the 'five sources' framework from the 1999 Standards "“ is seriously limited. Its limitation raises a significant barrier to understanding the nature of comprehensive validation, and this presents a significant threat to effective validation practice. Motivated by a belief that 'validity by design' ought to be substantiated through 'validation of design' this paper demonstrates the importance of adopting a broader conceptual framework. It introduces a new framework, based upon the metaphor of different validation lenses through which to scrutinize assessment procedures at differing levels of detail, with micro-validation lenses at one end of a continuum and macro-validation lenses at the other. The evolution of validation theory can be seen as a very gradual, if somewhat reluctant, acknowledgement of the importance of micro-validation. This paper recommends micro-validation as the natural foundation for any comprehensive validation program.