Abstract

The history of the Apgar score, an index of overall infant wellbeing just after birth, can help philosophers understand why instrument validation often seems to come short in practice and why clinicians continue to ‘misuse’ standardized instruments. I propose extending concerns about measurement realization (as being an integral part of epistemology of measurement) to constructs – that is, construct realizations. This involves including a new domain for operational coherence – clinical judgments – which themselves have a scale which may differ from the property we believe ourselves to be measuring. When the main purpose of a measuring practice is to arrive at this kind of clinical judgment, the scale of possible judgments (or courses of care) becomes how we experience the outcome of the measuring process itself. From the scale of possible judgments which results from measurement outcomes, we can deduce the construct as it is actually experienced by those involved. To understand measurement validation practices of the past or present, we must concern ourselves with construct realization; that is, what the construct actually turns out to be as it is experienced by patients, providers, and health systems.