Delirium Care Pathways

Delirium Diagnostic Tools

Page last updated: 07 November 2011

Brief description of diagnostic tools for delirium

Confusion Assessment Method (CAM)

The CAM is a valid and reliable diagnostic tool for delirium. It was specifically designed for use with the hospitalised older person, to improve delirium identification and recognition. It provides a standardised method to enable non-psychiatric clinicians to detect delirium quickly. The CAM was developed by Inouye et al in 1988-1990 and its performance attributes have been assessed in a number of studies.


Confusion Assessment Method – Intensive Care Unit (CAM-ICU)

The CAM-ICU is a modified version of the CAM intended for use in intensive care units. CAM-ICU is a delirium assessment instrument for use by nurses and physicians, and comprises standardised non-verbal assessments for mechanically ventilated and non-ventilated ICU patients. It was developed by Ely et al in 1999 and its performance attributes have been assessed by its developers in two studies.


Delirium Symptom Interview (DSI)

The DSI is an interview protocol for assessing the seven symptom domains delineated by the DSM-III criteria for delirium. It was developed by Albert et al in 1990-1992 and was designed to be administered (on a daily basis) to hospitalised older people by non-clinicians. The DSI is meant to be used in combination with other data to define cases of delirium and as an alternative to the DSM-III or DSM-III-R diagnostic criteria. Only one study has assessed its performance attributes.


Delirium Rating Scale (DRS)

Although the DRS was originally developed to ‘rate the symptoms’ of delirium, not as a diagnostic instrument, the study by Rosen et al (1994) assessed the DRS for its ability to accurately diagnose delirium when administered by research clinicians. A number of studies have assessed the performance attributes of this instrument when used as originally intended.




Adapted from: Clinical Epidemiology and Health Services Evaluation Unit 2006, Clinical Practice Guidelines for the Management of Delirium in Older People, Victorian Government Department of Human Services, Melbourne, Victoria