4AT
The 4 'A's Test (4AT) is a bedside medical scale used to help determine if a person has positive signs for delirium.[1] The test is designed to be used as a detection tool in the general clinical settings, inpatient hospital setting outside of the Intensive Care Unit (ICU), or in the community. The 4AT is intended to be used by healthcare practitioners without the need for special training, and it takes around two minutes to complete.[2] The test was first published online in 2011.[2]
The 4AT has been evaluated in multiple diagnostic test accuracy studies[3] and it is used in both clinical practice[4][5][6][7][8][9] and research.[10][11][12][13] It has been included in clinical guidelines and policy documents.[14][15][16]
Summary of the test
Full 4AT scale | ||
---|---|---|
Parameters and scoring | Points | |
[1] Alertness
This includes patients who may be markedly drowsy (eg. difficult to rouse and/or obviously sleepy during assessment) or agitated/hyperactive. Observe the patient. If asleep, attempt to wake with speech or a gentle touch on the shoulder. Ask the patient to state their name and address to assist rating. | ||
Normal (fully alert, but not agitated, throughout assessment)
Mild sleepiness for <10 seconds after waking, then normal Clearly abnormal |
0
0 4 | |
[2] AMT4
Age, date of birth, place (name of the hospital or building), current year. | ||
No mistakes
1 mistake 2 or more mistakes/untestable |
0
1 2 | |
[3] Attention
Ask the patient: “Please tell me the months of the year in backwards order, starting at December.”To assist initial understanding one prompt of “what is the month before December?” is permitted. | ||
Achieves 7 months or more correctly
Starts but scores <7 months / refuses to start Untestable (cannot start because unwell, drowsy, inattentive) |
0
1 2 | |
[4] Acute change or fluctuating course
Evidence of significant change or fluctuation in alertness, cognition, other mental function (eg. paranoia, hallucinations) arising over the last 2 weeks and still evident in the last 24hrs | ||
No
Yes |
0
4 | |
4AT TOTAL SCORE | ||
SCORING KEY
4 or above: possible delirium +/- cognitive impairment 1-3: possible cognitive impairment 0: delirium or severe cognitive impairment unlikely (Delirium still possible if [4] information incomplete) |
The 4AT has 4 parameters: [1] Alertness, [2] Abbreviated Mental Test-4 (AMT4), [3] Attention (Months Backwards test), and [4] Acute Change or Fluctuating Course (see table). The score range is 0–12, with scores of 4 or more suggesting possible delirium. Scores of 1-3 suggest possible cognitive impairment.
There are several indications of a positive score of 4 or more. Parameters [1] and [4] can each individually trigger a positive score. The rationale is that both altered arousal and acute change in mental functioning are highly specific indicators of delirium.[17][18][19][20]
Parameters [2] and [3] provide embedded cognitive testing. These parameters can also yield an overall positive score for the 4AT: if [2] scores as 2 or more mistakes or if the patient is untestable, and with [3] the patient is untestable, then the combined score is 4, suggesting possible delirium. The rationale for allowing untestability to trigger an outcome of possible delirium is that many people with delirium are too drowsy or inattentive to undergo cognitive testing or interview.[21][20] These scoring options additionally allow the 4AT to be completed in patients who are unable to provide verbal responses.
Psychometric properties
A systematic review and meta-analysis of data to 21 December 2019 involving 17 studies with a total of 3701 observations reported a pooled sensitivity of 88% and a pooled specificity of 88% for delirium diagnosis.[3] The current range of studies spans emergency department, medical, surgical and community settings.
Recommended use in clinical practice
The 4AT is intended to be used to assess for delirium on initial presentation with the patient, in transitions of care, and when delirium is suspected.[22]It is not intended to be routinely performed multiple times per day. The orientation and attention cognitive tests are not designed to be used repeatedly because of the burden on staff and patients, and because of practice effects.
Shorter tests such as the National Early Warning Score - 2 (NEWS2),[23] RADAR,[24] the Delirium Observation Scale (DOS),[25] the (Single Question in Delirium (SQiD),[26] or the Nursing Delirium Screening Scale (Nu-DESC)[27] are more suitable for ongoing routine monitoring for new delirium after admission to hospital (or in long-term care settings). A positive score in those tests generally then requires a more detailed assessment with a tool like the 4AT. This is an area of delirium practice which requires additional research.
The 4AT is one of several other delirium assessment tools in the literature. Each varies in its intended use (research, severity grading, very brief screening, etc.), completion time, need for training, and psychometric characteristics.[28][29][30][31]
Languages
The 4AT has to date been translated into German, French, Italian, Spanish, Danish, Finnish, Turkish, Arabic, Norwegian, Thai, Cantonese, Putonghua, Russian, Korean and Icelandic.[22]
References
- Delirium, Symptom Finder online.
- "4AT – RAPID CLINICAL TEST FOR DELIRIUM". Retrieved 14 May 2020.
- Tieges, Zoë; MacLullich, Alasdair M. J.; Anand, Atul; Brookes, Claire; Cassarino, Marica; O'Connor, Margaret; Ryan, Damien; Saller, Thomas; Arora, Rakesh C.; Chang, Yue; Agarwal, Kathryn (2020-06-12). "Diagnostic Accuracy of the 4AT for delirium detection: systematic review and meta-analysis". medRxiv: 2020.06.11.20128280. doi:10.1101/2020.06.11.20128280. S2CID 219602662.
- "National Audit of Dementia Reports and Resources". RC PSYCH ROYAL COLLEGE OF PSYCHIATRISTS. Retrieved 14 May 2020.
- "National Hip Fracture Database: Annual Report 2019" (PDF). National Hip Fracture Database. Retrieved 14 May 2020.
- MacLullich, AM; Shenkin, SD; Goodacre, S; Godfrey, M; Hanley, J; Stíobhairt, A; Lavender, E; Boyd, J; Stephen, J; Weir, C; MacRaild, A; Steven, J; Black, P; Diernberger, K; Hall, P; Tieges, Z; Fox, C; Anand, A; Young, J; Siddiqi, N; Gray, A (August 2019). "The 4 'A's test for detecting delirium in acute medical patients: a diagnostic accuracy study". Health Technology Assessment (Winchester, England). 23 (40): 1–194. doi:10.3310/hta23400. PMC 6709509. PMID 31397263.
- Dormandy, L; Mufti, S; Higgins, E; Bailey, C; Dixon, M (October 2019). "Shifting the focus: A QI project to improve the management of delirium in patients with hip fracture". Future Healthcare Journal. 6 (3): 215–219. doi:10.7861/fhj.2019-0006. PMC 6798014. PMID 31660529.
- Bearn, A; Lea, W; Kusznir, J (29 November 2018). "Improving the identification of patients with delirium using the 4AT assessment". Nursing Older People. 30 (7): 18–27. doi:10.7748/nop.2018.e1060. PMID 30426731.
- E, Vardy; N, Collins; U, Grover; R, Thompson; A, Bagnall; G, Clarke; S, Heywood; B, Thompson; L, Wintle (2020-05-16). "Use of a Digital Delirium Pathway and Quality Improvement to Improve Delirium Detection in the Emergency Department and Outcomes in an Acute Hospital". Age and Ageing. 49 (4): 672–678. doi:10.1093/ageing/afaa069. PMID 32417926.
- Casey, P; Cross, W; Mart, MW; Baldwin, C; Riddell, K; Dārziņš, P (March 2019). "Hospital discharge data under-reports delirium occurrence: results from a point prevalence survey of delirium in a major Australian health service". Internal Medicine Journal. 49 (3): 338–344. doi:10.1111/imj.14066. PMID 30091294. S2CID 205209486.
- Bellelli, PG; Biotto, M; Morandi, A; Meagher, D; Cesari, M; Mazzola, P; Annoni, G; Zambon, A (December 2019). "The relationship among frailty, delirium and attentional tests to detect delirium: a cohort study". European Journal of Internal Medicine. 70: 33–38. doi:10.1016/j.ejim.2019.09.008. PMID 31761505.
- Bellelli, G; Morandi, A; Di Santo, SG; Mazzone, A; Cherubini, A; Mossello, E; Bo, M; Bianchetti, A; Rozzini, R; Zanetti, E; Musicco, M; Ferrari, A; Ferrara, N; Trabucchi, M; Italian Study Group on Delirium, (ISGoD). (18 July 2016). ""Delirium Day": a nationwide point prevalence study of delirium in older hospitalized patients using an easy standardized diagnostic tool". BMC Medicine. 14: 106. doi:10.1186/s12916-016-0649-8. PMC 4950237. PMID 27430902.
- Davis, D; Richardson, S; Hornby, J; Bowden, H; Hoffmann, K; Weston-Clarke, M; Green, F; Chaturvedi, N; Hughes, A; Kuh, D; Sampson, E; Mizoguchi, R; Cheah, KL; Romain, M; Sinha, A; Jenkin, R; Brayne, C; MacLullich, A (9 February 2018). "The delirium and population health informatics cohort study protocol: ascertaining the determinants and outcomes from delirium in a whole population". BMC Geriatrics. 18 (1): 45. doi:10.1186/s12877-018-0742-2. PMC 5807842. PMID 29426299.
- "SIGN 157 Delirium: Risk reduction and management of delirium". www.sign.ac.uk. Retrieved 14 May 2020.
- "Delirium Clinical Care Standard" (PDF). Australian Commission on Safety and Quality in Health Care. Retrieved 14 May 2020.
- "National Early Warning Score (NEWS) 2. Standardising the assessment of acute-illness severity in the NHS. Additional Implemenation Guidance March 2020". Retrieved 2 June 2020.
- Inouye, S. K.; van Dyck, C. H.; Alessi, C. A.; Balkin, S.; Siegal, A. P.; Horwitz, R. I. (1990-12-15). "Clarifying confusion: the confusion assessment method. A new method for detection of delirium". Annals of Internal Medicine. 113 (12): 941–948. doi:10.7326/0003-4819-113-12-941. ISSN 0003-4819. PMID 2240918.
- Tieges, Zoë; McGrath, Aisling; Hall, Roanna J.; Maclullich, Alasdair M. J. (December 2013). "Abnormal level of arousal as a predictor of delirium and inattention: an exploratory study". The American Journal of Geriatric Psychiatry. 21 (12): 1244–1253. doi:10.1016/j.jagp.2013.05.003. ISSN 1545-7214. PMID 24080383.
- Chester, Jennifer G.; Beth Harrington, Mary; Rudolph, James L.; VA Delirium Working Group (May 2012). "Serial administration of a modified Richmond Agitation and Sedation Scale for delirium screening". Journal of Hospital Medicine. 7 (5): 450–453. doi:10.1002/jhm.1003. ISSN 1553-5606. PMC 4880479. PMID 22173963.
- European Delirium Association; American Delirium Society (2014-10-08). "The DSM-5 criteria, level of arousal and delirium diagnosis: inclusiveness is safer". BMC Medicine. 12: 141. doi:10.1186/s12916-014-0141-2. ISSN 1741-7015. PMC 4177077. PMID 25300023.
- Yates, Catherine; Stanley, Neil; Cerejeira, Joaquim M.; Jay, Roger; Mukaetova-Ladinska, Elizabeta B. (March 2009). "Screening instruments for delirium in older people with an acute medical illness". Age and Ageing. 38 (2): 235–237. doi:10.1093/ageing/afn285. ISSN 1468-2834. PMID 19110484.
- "4AT – RAPID CLINICAL TEST FOR DELIRIUM". Retrieved 2020-05-14.
- "NEWS2: Additional implementation guidance". RCP London. 2020-04-06. Retrieved 2020-06-18.
- Voyer, Philippe; Champoux, Nathalie; Desrosiers, Johanne; Landreville, Philippe; McCusker, Jane; Monette, Johanne; Savoie, Maryse; Richard, Sylvie; Carmichael, Pierre-Hugues (2015). "Recognizing acute delirium as part of your routine [RADAR]: a validation study". BMC Nursing. 14: 19. doi:10.1186/s12912-015-0070-1. ISSN 1472-6955. PMC 4384313. PMID 25844067.
- Schuurmans, Marieke J.; Shortridge-Baggett, Lillie M.; Duursma, Sijmen A. (2003). "The Delirium Observation Screening Scale: a screening instrument for delirium". Research and Theory for Nursing Practice. 17 (1): 31–50. doi:10.1891/rtnp.17.1.31.53169. ISSN 1541-6577. PMID 12751884. S2CID 219203272.
- Sands, M. B.; Dantoc, B. P.; Hartshorn, A.; Ryan, C. J.; Lujic, S. (September 2010). "Single Question in Delirium (SQiD): testing its efficacy against psychiatrist interview, the Confusion Assessment Method and the Memorial Delirium Assessment Scale". Palliative Medicine. 24 (6): 561–565. doi:10.1177/0269216310371556. ISSN 1477-030X. PMID 20837733. S2CID 40306973.
- Hargrave, Anita; Bastiaens, Jesse; Bourgeois, James A.; Neuhaus, John; Josephson, S. Andrew; Chinn, Julia; Lee, Melissa; Leung, Jacqueline; Douglas, Vanja (November 2017). "Validation of a Nurse-Based Delirium-Screening Tool for Hospitalized Patients". Psychosomatics. 58 (6): 594–603. doi:10.1016/j.psym.2017.05.005. ISSN 1545-7206. PMC 5798858. PMID 28750835.
- De, J; Wand, AP (December 2015). "Delirium Screening: A Systematic Review of Delirium Screening Tools in Hospitalized Patients". The Gerontologist. 55 (6): 1079–99. doi:10.1093/geront/gnv100. PMID 26543179.
- Pérez-Ros, P; Martínez-Arnau, FM (30 January 2019). "Delirium Assessment in Older People in Emergency Departments. A Literature Review". Diseases. 7 (1): 14. doi:10.3390/diseases7010014. PMC 6473718. PMID 30704024.
- Rieck, KM; Pagali, S; Miller, DM (March 2020). "Delirium in hospitalized older adults". Hospital Practice (1995). 48 (sup1): 3–16. doi:10.1080/21548331.2019.1709359. PMID 31874064.
- "Adult Delirium Measurement Info Cards – NIDUS". Retrieved 14 May 2020.