Capturing the ghost in the machine: a process for development and validation of measures of phenomenal consciousness in delirium.
Age and ageing July 2, 2024 Eamonn Eeles, David Duc Tran, Sarah Ward et al.
A set of candidate measures for assessing phenomenal consciousness in delirium has been developed and validated. Delirium is traditionally considered a disorder of consciousness, but clinical assessments of alertness and arousal are insufficient for a dimensional evaluation. A narrative review of 814 articles identified 14 existing tools across three domains of phenomenal consciousness—prereflective consciousness, phenomenal-sensed experience, and reflective thought—but only one met eligibility criteria for delirium assessment. Fifty-seven new tests were generated using the silent generation technique, later reduced to 26 and then 22 after content validity evaluation. The scale average content validity index was 0.89, inter-rater agreement ranged from 80% to 97%, and face validity was 100% positive. The Flesch Reading Ease Score was 91.6, indicating very easy readability. Early validation results are promising.