DOMS: Delirium Measures & Tools

Delirium is a rapid but reversible change in cognitive functioning characterised by confusion, hallucinations, misinterpretation of events and sleep disturbance, which usually results from an acute but potentially treatable physiological condition such as drug intoxication, fever or cardiovascular disorder.

The accurate detection and discrimination of delirium from dementia is an important task particularly in acute hospital settings.

The following measures are covered by DOMS:

Authors: Inouye et al., 1990
Quality Rating: Very good
Time Required: 5 min

The CAM is a structured questionnaire developed as a brief screen for delirium. It is designed for use in older persons at high risk of developing delirium (e.g., older medical and surgical inpatients). Scores on the CAM agree favourably with a diagnosis of delirium based on DSM-IV criteria. It can also distinguish persons with delirium-only from those with delirium superimposed on dementia, an clinically important distinction since the latter strongly predicts a worse medical outcome. When the CAM is used alongside cognitive testing the differential diagnosis of dementia from delirium can be enhanced.

The CAM is very widely utilised and has been translated into several languages. A 3 minute diagnostic version (3D-CAM) has been validated, the CAM has also been adapted to intensive care settings (CAM-ICU), and is appropriate in emergency department settings. The DRS-R-98 is recommended if more detailed testing is required.

The Confusion Assessment Method (CAM) is administered by a healthcare professional or clinical staff who complete a brief structured questionnaire. Formal psychiatric training is not required to administer the CAM, however, a number of factors are essential to attaining high diagnostic sensitivity:
i) training in the use of the scale,
ii) using it with concurrent cognitive testing and
iii) when the patient shows positive CAM results a proper diagnostic investigation of delirium should be conducted.

Permissions & Cost:
The CAM is available free of charge for non profit clinical and academic uses, and can be downloaded after agreeing to the terms of the disclaimer. Permission for other purposes can be obtained via the Aging Brain Center.

Downloads & Tools:

  • Test form
  • Manual

  • Inouye, S. K., Vandyck, C. H., Alessi, C. A., Balkin, S., Siegal, A. P., & Horwitz, R. I. (1990). Clarifying confusion: The Confusion Assessment Method: A new method for detection of delirium. Annals of Internal Medicine, 113(12), 941–948.
  • González, M. (2004). Instrument for Detection of Delirium in General Hospitals: Adaptation of the Confusion Assessment Method. Psychosomatics, 45(5), 426.
  • Marcantonio, E. R., Ngo, L. H., O’Connor, M., Jones, R. N., Crane, P. K., Metzger, E. D., & Inouye, S. K. (2014). 3D-CAM: derivation and validation of a 3-minute diagnostic interview for CAM-defined delirium: a cross-sectional diagnostic test study. Annals of Internal Medicine, 161(8), 554–561.
  • Monette, J., Galbaud du Fort, G., Fung, S. H., Massoud, F., Moride, Y., Arsenault, L., & Afilalo, M. (2001). Evaluation of the confusion assessment method (CAM) as a screening tool for delirium in the emergency room. General Hospital Psychiatry, 23(1), 20–25.
  • Authors: Trzepacz et al., 1998
    Quality Rating: Good
    Time Required: 15–20 mins

    The DRS-R-98 is a comprehensive scale designed to measure delirium and its severity. It is a revised version of the original DRS scale and be applied to persons with or without dementia. It has excellent inter-rater reliability and can distinguish persons with delirium versus illness due to other causes (e.g., schizophrenia, dementia, depression). The DRS-R-98 can also distinguish persons with delirium-only from those with delirium superimposed on dementia, an extremely important distinction since the latter strongly predicts a more adverse medical outcome.

    The DRS-R-98 has been translated into several languages. For more rapid testing by non-specialists the CAM may be more appropriate.

    The Delirium Rating Scale, Revised-98 (DRS-R-98) is administered by healthcare professional or clinical staff who complete a brief structured questionnaire.

    Permissions & Cost:
    Free of charge to healthcare professionals for non-commercial clinical or research purposes. For other uses, please contact the original authors to seek permission.

    Downloads & Tools:

  • Test form
  • Instructions
  • Answer sheet

  • Trzepacz, P.T., Baker, R.W., & Greenhouse, J. (1988). A symptom rating scale for delirium. Psychiatry Research, 23(1), 89–97.
  • Trzepacz, P. T., Mittal, D., Torres, R., Kanary, K., Norton, J., & Jimerson, N. (2001). Validation of the Delirium Rating Scale-revised-98: Comparison with the Delirium Rating Scale and the Cognitive Test for Delirium. Journal of Neuropsychiatry and Clinical Neurosciences, 13(2), 229–242.