A classification of delirium assessment tools

Something that I had initially found confusing in the field of delirium was the sheer number of tools that have been developed. A huge variety. And it was not always clear what each one was for and how it should be used.

So recently I thought I would try to find all the tools that had been published, aiming to include only those tools specifically designed for delirium assessment. I included tools that had a specific delirium subscale. I did not include general cognitive tests that have been used to assess delirium.

To start, here is a timeline of all published delirium tools, by first publication date. The references for these tools are not available from a single source. The reviews, book chapter and websites below together provide all the references.


A timeline of all published delirium assessment tools

1973 Delirium Scale (D-Scale)

1985 Global Accessibility Rating Scale (GARS)

1987 Organic Brain Syndome Scale (OBS)

1988 Delirium Rating Scale (DRS); Saskatoon Delirium Checklist (SDC)

1990 Confusion Assessment Method (CAM); Clinical Assessment of Confusion-A & -B (CAC-A, CAC-B)

1991 Confusion Rating Scale (CRS), MCV Nursing Delirium Rating Scale (MCV-NDRS)

1992 Delirium Symptom Interview (DSI)

1993 Delirium Rating Scale - Revised - 98 (DRS-R98);

1994 Delirium Assessment Scale (DAS)

1996 Cognitive Test for Delirium (CTD); NEECHAM Confusion Scale (NCS)

1997 Confusional State Evaluation (CSE); Memorial Delirium Assessment Scale (MDAS); Global Attentiveness Rating

1998 Delirium Index (DI); Delirium Severity Scale (DSS)

2001 Confusion Assessment Method for the ICU (CAM-ICU); Intensive Care Delirium Screening Checklist (ICDSC); Delirium Rating Scale - Revised - 98 (DRS-R98); Communication Capacity Scale & Agitation Distress Scale (CCS & ADS)

2002 Delirium Experience Questionnaire (DEQ)

2003 Delirium Observation Scale (DOS)

2004 Pediatric Anesthesia Emergence Delirium Scale (PAED)

2005 Nursing Delirium Screening Scale (Nu-DESC); Delirium-O-Meter; Delirium Detection Score

2008 Delirium Motor Subtype Scale (DMSS)

2010 Single Question in Delirium (SQiD); Delirium Diagnostic Tool-provisional (DDT-Pro); Delirium Box (Delbox)

2011 4 ‘A’s Test (4AT); Pediatric Confusion Assessment Method for the Intensive Care Unit (pCAM-ICU)

2012 Modified Richmond Agitation Sedation Scale (mRASS): Family Confusion Assessment Method (FAM-CAM)

2013 Brief CAM (bCAM); Delirium Triage Screen (DTS); Informant Assessment of Geriatric Delirium (I-AGeD); Observational Scale for Level of Alertness (OSLA)

2014 3D-Confusion Assessment Method (3D-CAM); Modified Confusion Assessment Method for the Emergency Department (mCAM-ED); Abbreviated version of the Delirium Motor Subtyping Scale (DMSS-4); Confusion Assessment Method – Severity Scale (CAM-S); Cornell Assessment of Pediatric Delirium (CAPD)

2015 Recognizing Acute Delirium As part of your Routine (RADAR); Simple Question for Easy Evaluation of Consciousness (SQEEC); Ultra-Brief 2-item Screener (UB-2); Single Screening Question Delirium (SSQ–Delirium); DelApp

2016 Preschool Confusion Assessment Method—Intensive Care Unit (psCAM-ICU); Sour Seven; Delirium Early Monitoring System (DEMS)

2017 Confusion Assessment Method for the ICU - 7 (CAM-ICU-7); National Early Warning Score - 2 (NEWS2);

2018 Stanford Proxy Test for Delirium (S-PTD); Sophia Observation Withdrawal Symptoms – Pediatric Delirium (SOS-PD)

2020 Ultra-Brief Confusion Assessment Method (UB-CAM)


With 60 (!) tools dating back from 1973 it is difficult to grasp how all these tools might be used. So I thought that I would like to classify the available tools. This could help in narrowing down the options according to what the reader might be looking for.

One important distinction in tools used in clinical practice is between tools used episodically, and tools used for inpatient monitoring for new delirium. I covered this topic in another blog.

It is also important to note that some tools have more than use. Some are used both in detection and severity rating, for example.


Categories of delirium assessment tools

  • Use at first presentation or at any other times when delirium is suspected (episodic testing)

  • Monitoring for new onset delirium in inpatients, usually carried out daily or more

  • Use in intensive care units

  • Ultra-brief bedside tools

  • Detailed phenomenological and/or neuropsychological assessment

  • Informant tools

  • Measurement of delirium severity

  • Motor symptoms assessment

  • Cognitive tests designed for delirium

  • Assessment of delirium in children


Classification of delirium assessment tools: table


Episodic use: at the front door or at any other times when delirium is suspected

Confusion Assessment Method (CAM)

4 'A's Test (4AT)

Brief Confusion Assessment Method (bCAM)

Modified CAM for the Emergency Department (mCAM-ED)

3D-Confusion Assessment Method (3D-CAM)

Delirium Diagnostic Tool-provisional (DDT-Pro)


Monitoring for new onset delirium in inpatients, usually carried out daily or more

Single Question in Delirium (SQiD)

Nursing Delirium Screening Scale (Nu-DESC)

Delirium Observation Scale (DOS)

National Early Warning Score - 2 (NEWS2)

Recognising Delirium As part of your Routine (RADAR)

Neecham Confusion Scale (NCS)

Confusion Rating Scale (CRS)

Stanford Proxy Test for Delirium (S-PTD)

Delirium Early Monitoring System (DEMS)

Use in intensive care units (ICU)

Confusion Assessment Method for the ICU (CAM-ICU)

Intensive Care Delirium Screening Checklist (ICDSC)

Delirium Detection Score (DDS)

MCV Nursing Delirium Rating Scale (MCV-NDRS)

Ultra-brief bedside tools

Ultra-brief 2-item screener (UB-2)

Ultra-Brief Confusion Assessment Method (UB-CAM)

Delirium Triage Screen (DTS)

Modified Richmond Agitation Sedation Scale (mRASS)

Simple Question for Easy Evaluation of Consciousness (SQEEC)

Observational Scale for Level of Alertness (OSLA)

Global Accessibility Rating Scale (GARS)

Detailed research assessment

Delirium Rating Scale (DRS)

Delirium Rating Scale - Revised - 98 (DRS-R98)

Cognitive Test for Delirium (CTD)

Delirium Symptom Interview (DSI)

Saskatoon Delirium Checklist (SDC)

Organic Brain Syndrome scale (OBS)

Delirium Scale (D-Scale)

Clinical Assessment of Confusion A & B (CAC-A, CAC-B)

Informant tools

Single Question in Delirium (SQiD)

Single Screening Question Delirium (SSQ–Delirium)

Family Confusion Assessment Method (FAM-CAM)

Informant Assessment of Geriatric Delirium (I-AGeD)

Sour Seven

Measurement of delirium severity

Delirium Rating Scale (DRS)

Delirium Rating Scale - Revised - 98 (DRS-R98)

Confusion Assessment Method - Severity (CAM-S)

Confusion Assessment Method for the - ICU - 7 (CAM-ICU-7)

3D-Confusion Assessment Method (3D-CAM)

Memorial Delirium Assessment Scale (MDAS)

Delirium Detection Score (DDS)

Confusional State Evaluation (CSE)

Delirium Index (DI)

Delirium Severity Scale (DSS)

Delirium Assessment Scale (DAS)

Delirium-O-Meter (DOM)

Delirium Observation Scale (DOS)

Communication Capacity Scale & Agitation Distress Scale (CCS & ADS)

Motor symptoms assessment

Delirium Motor Symptom Scale (DMSS)

Delirium Motor Symptom Scale - 4 (DMSS-4)

Cognitive tests designed for delirium

Delbox

DelApp

Assessment of delirium in children

Cornell Assessment of Pediatric Delirium (CAPD)

Pediatric Anesthesia Emergence Delirium Scale (PAED)

Pediatric Confusion Assessment Method-Intensive Care Unit (pCAM-ICU)

Preschool Confusion Assessment Method-Intensive Care Unit (psCAM-ICU)

Sophia Observation Withdrawal Symptoms-Pediatric Delirium (SOS-PD)


References

De J, Wand AP. Delirium Screening: A Systematic Review of Delirium Screening Tools in Hospitalized Patients. Gerontologist. 2015;55(6):1079-1099. doi:10.1093/geront/gnv100

Grover S, Kate N. Assessment scales for delirium: A review. World J Psychiatry. 2012;2(4):58-70. doi:10.5498/wjp.v2.i4.58

NIDUS Measurement Info Cards: https://deliriumnetwork.org/measurement/delirium-info-cards/ Accessed 14 July 2020.

Robertsson, B. The instrumentation of delirium. In: Lindesay J, Rockwood K, Macdonald A. Delirium in Old Age. Oxford 2002.

Trzepacz PT. A review of delirium assessment instruments. Gen Hosp Psychiatry. 1994;16(6):397-405. doi:10.1016/0163-8343(94)90115-5

van Velthuijsen EL, Zwakhalen SM, Warnier RM, Mulder WJ, Verhey FR, Kempen GI. Psychometric properties and feasibility of instruments for the detection of delirium in older hospitalized patients: a systematic review. Int J Geriatr Psychiatry. 2016;31(9):974-989. doi:10.1002/gps.4441