FAQ

The 4AT is a brief bedside assessment tool used for the rapid initial detection of delirium and cognitive impairment in clinical settings. It takes less than 2 minutes to administer and consists of 4 items: Alertness, AMT4 (Abbreviated Mental Test - 4), Attention (Months Backwards test), and Acute change or fluctuating course. A key feature is that it does not require special training to use.

The 4AT was developed in 2011 to address challenges associated with existing delirium screening tools. At that time, implementing the recommended tools in routine clinical practice proved difficult due to several factors:​

• Training Requirements: Existing tools necessitated formal training, which was resource-intensive and time-consuming, hindering widespread adoption.​

• Low Detection Rates: In practice, these tools often failed to identify delirium effectively, with issues such as incomplete assessments, false negatives, or frequent 'Unable to Assess' (UTA) ratings, especially in patients unable to participate in cognitive testing.​

To overcome these limitations, the 4AT was designed with the following objectives:​

• Simplicity and Speed: A brief assessment (typically under two minutes) that could be easily integrated into routine care without the need for special training.​

• Assessment of Core DSM Diagnostic Features: Incorporation of key clinical features of delirium, including alertness, cognitive function, attention, and acute changes or fluctuations in mental status.​
  

• Inclusivity: Ability to assess patients who are uncooperative or unable to engage in traditional cognitive testing, ensuring that no patient is categorized as 'UTA' solely due to their condition.​

The development of the 4AT involved iterative testing and refinement based on real-world clinical feedback, leading to a tool that balances diagnostic accuracy with practical applicability in diverse healthcare settings.

The 4AT was originally designed in 2011 by Prof Alasdair MacLullich (Edinburgh Delirium Research Group, University of Edinburgh, Scotland), and Dr Tracy Ryan and Dr Helen Cash (NHS Lothian, Scotland). Updates since then have been carried out by and are the responsibility of Alasdair MacLullich.

The primary purpose of the 4AT is the rapid clinical detection of delirium. Identifying delirium early is crucial as it prompts the search for underlying causes, allows initiation of appropriate management strategies (like delirium care bundles), helps prevent complications (e.g., falls, pressure sores), and ultimately aims to improve patient outcomes. The tool can also help identify previously unrecognized cognitive impairment.

○ Rapid: Administration typically takes less than 2 minutes.

○ Simple to Use: Designed for use by any healthcare professional without requiring specific training courses.

○ Inclusive Assessment: Includes a method for scoring patients who are 'untestable' (e.g., too drowsy or agitated to participate in cognitive testing), ensuring all patients can be assessed and avoiding 'Unable to Assess' outcomes.

○ Evidence-Based: Extensively validated in over 33 studies involving more than 6,000 patients across diverse clinical settings.

○ Widely Recommended: Included as a recommended delirium assessment tool in major international clinical guidelines (e.g., UK NICE and SIGN guidelines; USA American Psychiatric Association guidelines)

○ Free Access: The 4AT is free for all uses (clinical, quality improvement, research, education) and can be downloaded and integrated into Electronic Health Records (EHR/EMR) without permission or registration.

The 4AT is designed for assessing adults in various clinical settings. It has been most extensively validated in older adults (typically aged 65 and over) and is suitable for use in patients with dementia.

Yes, the 4AT is completely free. No permission or registration is required for downloading, using, reproducing, or integrating the 4AT into local protocols or electronic health record systems (EHR/EMR).

The 4AT is included in multiple guidelines, good practice statements and clinical pathways across the world.

These include NICE guidelines (UK), SIGN guidelines (Scotland), American Psychiatric Association guidelines (USA).

See here for a list of prominent examples.

The 4AT yields a total score ranging from 0 to 12. The score is calculated by summing the points from the four individual items. A score of 4 or more suggests possible delirium and triggers further clinical assessment.

This item is scored based on observing the patient's level of alertness during the assessment.

○ Score 0: Patient is normally alert throughout the assessment (calm and interacts appropriately) OR shows only mild sleepiness for less than 10 seconds after being woken, then returns to normal alertness.

○ Score 4: Patient shows clearly abnormal alertness. This can be either marked drowsiness (e.g., difficult to rouse, falling asleep repeatedly during assessment) OR agitation/hyperactivity.

○ Guidance: Altered alertness (scoring 4) is a very strong indicator of delirium in general hospital patients.

The Abbreviated Mental Test - 4 assesses orientation. Ask the patient their: Age, Date of Birth, Place (name of the hospital or building), and the Current Year.

○ Score 0: Correctly answers all four questions.

○ Score 1: Makes one error.

○ Score 2: Makes two or more errors OR is 'untestable' (cannot provide meaningful answers due to drowsiness, severe inattention, communication barriers etc.).

This assesses attention using the Months of the Year Backwards test. Ask the patient: "Please tell me the months of the year in backwards order, starting at December." (Allow one prompt: "What is the month before December?").

○ Score 0: Correctly recites months backwards to June (i.e., 7 or more months correct).

○ Score 1: Starts the test but gets fewer than 7 months correct OR refuses to start the test.

○ Score 2: Is 'untestable' (cannot start the test because they are too unwell, drowsy, or inattentive).

This assesses if there is evidence of an acute change OR fluctuation in the patient's alertness, cognition (e.g., new confusion), or other mental function (e.g., new paranoia, hallucinations). The change must have occurred over the last 2 weeks and still be evident in the last 24 hours. This information often comes from collateral sources (staff, family, notes) or your own knowledge.

○ Score 0: No evidence of acute change or fluctuation.

○ Score 4: Clear evidence of acute change or fluctuation is present.

○ Guidance: Ask staff or family "Has there been a recent change in their confusion/alertness?". Acute change is highly suggestive of delirium.

If a patient cannot meaningfully attempt Item 2 (AMT4) or Item 3 (Attention) due to severe drowsiness, inattention, illness, or communication barriers, they are scored as 'untestable' for that specific item, receiving 2 points for each item they are untestable on.10

○ Rationale: This is a crucial feature. Severe impairment in arousal or attention that prevents cognitive testing is, itself, a key indicator of possible delirium (particularly hypoactive delirium). By assigning points for 'untestability', the 4AT ensures these vulnerable patients are not simply labelled 'Unable to Assess' (as might happen with other tools) and still flags them for potential delirium if the total score reaches 4 or more. This improves the tool's sensitivity in real-world practice.

It also avoids the very serious problem of missing delirium because of tool failure.

The total score provides an indication of the likelihood of delirium or cognitive impairment:

○ Score 0: Suggests that delirium or moderate-to-severe cognitive impairment is unlikely. However, delirium is still possible if Item 4 information was incomplete, or in cases of very mild/resolving delirium. Routine clinical care is usually appropriate, but monitoring may be needed for high-risk patients.

○ Score 1-3: Suggests possible cognitive impairment (e.g., dementia). Delirium is less likely than with higher scores but cannot be ruled out. Consider further cognitive assessment, gather informant history, and monitor for development of delirium.

○ Score 4 or more: Suggests possible delirium. This score should trigger an urgent clinical assessment to confirm the diagnosis, identify and treat underlying causes, and initiate appropriate delirium management protocols or care bundles. This score may also reflect underlying severe cognitive impairment (see question on dementia).

○ Clinical Judgement: Remember, though a score of 4+ on the 4AT strongly suggests delirium as per the large and supportive body of formal diagnostic test accuracy studies, clinical judgement is always required for diagnosis and management decisions. This of course applies to all delirium tools.

Local guidelines should always be followed. General recommendations based on the score are summarised in this table.

Yes, the 4AT is rigorously validated. Its diagnostic accuracy has been assessed in 33 published studies, encompassing more than 6,000 patients across diverse international clinical settings. The 4AT in fact has the largest body of formal diagnostic test accuracy studies of any delirium assessment tool.

The evidence base includes the initial validation study in geriatric inpatients, numerous subsequent studies in settings like emergency departments, acute medical and surgical wards, stroke units, oncology, palliative care, and care homes, and multiple systematic reviews and meta-analyses that pool data from these studies.

The large formal diagnostic test accuracy evidence base on the 4AT shows high sensitivity and specificity. A meta-analysis of 17 studies published in 2020 showed a pooled sensitivity of 88% and a pooled specificity of 88%.

Validation studies that have tested assess the 4AT's performance have used mostly used a 'reference standard' or 'gold standard' diagnosis of delirium. This reference standard is typically made by trained clinical experts (like geriatricians or psychiatrists) using formal diagnostic criteria, such as those from the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV or DSM-5) or the International Classification of Diseases (ICD). The high sensitivity and specificity values found in studies indicate that the 4AT score is closely aligned with these formal expert diagnoses.

• Yes, like any screening tool, the 4AT has limitations:

  • False Positives (Score ≥4 without delirium):

    • Overlap with Dementia: Patients with pre-existing dementia may score points on cognitive items (Items 2 & 3) due to their baseline impairment, potentially reaching a score ≥4 even without acute delirium. Item 4 (Acute Change) helps differentiate, but the numeric score can still be high. Specificity may be lower in those with severe dementia.

    • Communication Barriers: Severe language barriers or deafness, if not adequately addressed, could lead to points on cognitive items due to misunderstanding, not delirium. Always consider these factors.  

    • Severe Anxiety: Rarely, extreme anxiety might impair performance on attention tasks.  

  • False Negatives (Score <4 with delirium):

    • Fluctuating Delirium: Symptoms can fluctuate; a patient tested during a lucid interval might score low. Repeat assessment or collateral history about fluctuation is important.

    • Mild/Prodromal Delirium: Very subtle or early delirium might not be detected by the brief tests.

    • Rater Error: Incorrect administration (e.g., over-prompting) could lead to under-scoring.

    • Lucid Moments: Some delirious patients have brief periods of clarity where they might pass the short tests.

  • Other Limitations:

    • Cultural/Educational Factors: Months Backwards might be difficult for those unfamiliar with the sequence due to cultural or educational background, potentially leading to points without delirium. Days of the week backwards is a possible adaptation.  

  • Mitigation: Always interpret the 4AT in clinical context, use collateral history (especially for Item 4), consider baseline function, be aware of confounding factors (meds, communication issues), and reassess if clinical suspicion remains despite a low score. The benefits of improved detection generally outweigh the risk of occasional false positives.  

The 4AT is designed for rapid assessment and usually takes less than 2 minutes to complete in routine clinical practice.

Any healthcare professional who encounters patients at risk can administer the 4AT, including nurses, doctors, physician assistants, and allied health professionals. No specific training courses or certification are required. It was developed for straightforward application by a wide range of healthcare staff as part of their routine assessment. Familiarity with the items and scoring can be achieved by reviewing the tool and the user guide. A brief orientation session for teams can help ensure consistency.

The user should have knowledge of delirium including its main features.

The 4AT is best used as a test for delirium used at key points rather than multiple times per day to monitor for new onset delirium inpatients. Recommended times for use include:At initial hospital admission or presentation (e.g., in the Emergency Department or admission unit) [cite: 918, 80-82, 597-598].

• Before and after surgery (perioperatively).

• During transitions of care between wards or facilities.  

• Whenever delirium is suspected based on clinical observation or changes in the patient's mental status (e.g., new confusion reported by staff or family).

• Following a positive screen on a brief monitoring tool (e.g., SQiD, NuDESC).  

• Periodically (e.g., once daily) to track recovery from an episode of delirium.  

• Using the 4AT multiple times per day for extended periods solely for monitoring purposes is generally discouraged. However, some units do use the 4AT 1-2 times per day using Days of the Week Backwards in place of Months of the Year Backwards. 

• Settings: Validated and used in Emergency Departments, acute medical and surgical wards, geriatric/rehabilitation units, stroke services, oncology units, palliative care settings, care homes, and potentially outpatient/home visits if acute confusion arises.

Yes, the 4AT is versatile and has been validated and implemented in numerous clinical settings, including: Emergency Departments, acute medical and surgical wards, geriatric and rehabilitation units, stroke services, oncology units, palliative care settings (including hospices), and care homes.

The 4AT was primarily developed and validated for non-ICU settings. For patients in the ICU, especially those who are mechanically ventilated or deeply sedated, tools specifically designed for that environment, such as the CAM-ICU or the ICDSC, are the standard recommended tools. Current guidelines generally recommend CAM-ICU or ICDSC for routine ICU delirium assessment. The 4AT could potentially be used in ICU patients who are awake, extubated, and able to interact.

One recent study examined the 4AT in critically ill patients and found similar performance compared to CAM-ICU.

It's essential to consider communication challenges.

• Ensure optimal conditions: use hearing aids, glasses; ensure good lighting; minimize background noise; use professional interpreters if needed.

• Speak clearly and allow adequate time for responses.  Drowsiness/Unresponsiveness: Score Item 1 (Alertness) as 4. Score Items 2 (AMT4) and 3 (Attention) as 'untestable' (2 points each) if the patient cannot engage. This correctly flags possible delirium.  

• Aphasia/Non-Verbal: Score cognitive items as 'untestable' (2 points each) if verbal answers aren't possible. Observe alertness (Item 1) and seek collateral for acute change (Item 4). Non-verbal communication attempts can be used if appropriate.  

• Refusal/Agitation: Score Alertness as 4 if agitated. Score refused cognitive items as 'untestable' (2 points each). Document any challenges.  

• Language Barrier: Use professional interpreters or translated versions. If unavailable, cognitive items may have to be scored 'untestable' (2 points each). Note the limitation in documentation as the score might be falsely elevated.  

• Hearing Impairment: Use aids, speak clearly, write questions if needed. If understanding is impossible despite efforts, score as 'untestable' and note the potential for a false positive.  

• The 4AT's facility to use observation (Item 1) and collateral history (Item 4), plus its 'untestable' scoring which can lead to a positive score, makes it highly adaptable. Collateral information for Item 4 is particularly imporatnt when direct communication is limited.

Yes, the 4AT is suitable for use in patients with dementia and has been validated in cohorts including individuals with dementia.Yes, the 4AT is suitable for use in patients with dementia and has been validated in cohorts including individuals with pre-existing cognitive impairment.

• Delirium Detection: It helps identify delirium superimposed on dementia, which is common but challenging to diagnose. Good sensitivity is maintained in this group.  

• Specificity Consideration: In patients with severe dementia, specificity might be reduced. This is because profound baseline cognitive impairment could lead them to score points on Items 2 and 3 even without active delirium, potentially resulting in a score of 4.  

• Clinical Approach: A 4AT score of 4+ in someone with dementia warrants assessment for delirium. Differentiating delirium from underlying dementia requires careful clinical evaluation, focusing on acute changes from the patient's baseline mental state (Item 4 is key) and utilizing informant history whenever possible. The diagnosis remains clinical. If Item 4 is negative, a score of 4 might reflect chronic impairment rather than delirium.  

es, the 4AT has been translated into many languages to support its international use. Available translations include Italian, German, Spanish, Portuguese, Danish, French, Icelandic, Norwegian, Arabic, Finnish, Czech, Dutch, Polish, Swedish, Chinese (Mandarin and Cantonese), Turkish, Korean, Thai, Russian, Hebrew, and Japanese. Validated versions exist for several languages. The months backward task is generally adapted using local month names, though days of the week backwards has been used as an alternative in some adaptations.

You can find available translations here.

Yes. The 4AT is free to incorporate into EHR/EMR systems without licensing fees or specific permission. Many hospitals and healthcare systems have successfully embedded the 4AT into their digital platforms to facilitate routine screening, documentation, and data collection for quality improvement and research.

mplementing the 4AT offers several benefits:

• Early Detection: Facilitates prompt identification of delirium, allowing for timely interventions.  

• Improved Outcomes: Early detection and management can lead to reduced hospital stays, lower mortality rates, and better discharge outcomes (e.g., higher likelihood of discharge home).  

• Ease of Use: Simplicity and speed make it practical for routine use by various staff.  

• No Specialized Training Required: Promotes widespread adoption.  

• Risk Identification: Higher scores are associated with adverse outcomes, helping identify high-risk patients.  

Successful implementation involves integration into routines and staff education:

• Incorporate into Assessments: Make it part of admission checks (e.g., for ≥65 years), daily assessments in high-risk patients (e.g. post-operatively), or use whenever a mental status change is noted. Embed it in standard workflows.  

• Educate Staff: Conduct brief orientation sessions explaining delirium importance and how to use/score the 4AT. Use case examples for practice. Provide quick reference guides (pocket cards, posters).

• Clarify Next Steps: Ensure staff know the protocol for positive scores (e.g., ≥4 triggers physician notification, delirium work-up, safety measures).

• Integrate into Documentation: Add 4AT fields to EHR/paper forms. Required documentation improves compliance. Consider EHR alerts for positive scores.  

• Address Barriers: Emphasize speed (<2 mins) to counter time concerns. Use leadership support and champions to reinforce priority. Ensure clear follow-up actions motivate staff. Provide resources for communication barriers (interpreters, etc.).

• Monitor and Feedback: Track compliance rates and delirium detection rates. Share positive results and success stories with staff. Address ongoing issues.  

• Link to Care Pathway: Use 4AT as the first step in a broader delirium care pathway including diagnosis, investigation, and management (non-pharmacological interventions, order sets).

• Sustainability: Make it part of new staff orientation and annual refreshers.

• Studies show implementation is feasible and improves detection rates.

The CAM is a well-established algorithm for identifying delirium based on four key features. The 4AT was developed subsequently, aiming to provide a tool with greater brevity and ease of use for routine screening. Here’s a comparison:

• Training: The 4AT requires no specific training, designed for immediate use by diverse staff. CAM performance is generally enhanced by specific rater training and experience.

• Time: The 4AT typically takes less than 2 minutes. Standard CAM assessments often take around 5 minutes, depending on the cognitive tests used to inform its features.

• Scoring 'Untestable' Patients: The 4AT has a specific mechanism to score patients too drowsy or inattentive for cognitive testing, ensuring an assessment is completed. Standard CAM protocols may result in an 'Unable to Assess' outcome for such patients.

• Structure: The 4AT directly incorporates brief cognitive tests (AMT4, Months Backwards) and yields a score. CAM is an algorithm requiring the assessor to judge the presence of features, often informed by separate cognitive testing.

• Accuracy: Both tools are well-validated. In some comparisons, CAM demonstrates very high specificity, sometimes higher than the 4AT, particularly when used by trained experts. However, in a large direct comparison study, the 4AT showed substantially higher sensitivity than the CAM (76% vs 40% in that study), while CAM had higher specificity (100% vs 94%). The 4AT's extensive validation base (over 33 studies, >6000 patients) is the largest for any delirium tool.

• Practicality: The 4AT's speed, lack of training need, and ability to score all patients are significant practical advantages, facilitating implementation in busy clinical environments. Reflecting this, the 4AT is mentioned in multiple guidelines like NICE (2023), SIGN (2019), and the American Psychiatric Association (2025).

• Summary: While CAM has a long history and can achieve high specificity, the 4AT offers pragmatic advantages in speed, ease of use, and inclusivity, supported by a very large evidence base across diverse settings [cite: 943, 451-452].
  
  Please see this table for a comparison of the CAM and the 4AT.

○ NuDESC (Nursing Delirium Screening Scale): This is an observational monitoring tool, typically completed by nurses based on observations over a shift. It does not involve direct patient cognitive testing. It's useful for ongoing monitoring of inpatients for new delirium onset. The 4AT is designed more to be used at specific time points or when delirium is suspected. NuDESC and 4AT serve different but complementary roles in delirium detection pathways.

The DOSS is primarily an observational screening tool, often used by nurses to monitor patients for delirium symptoms over a shift.

• Focus: DOSS relies on observing behaviours related to delirium features, whereas the 4AT combines observation (Alertness, Acute Change) with direct cognitive testing (AMT4, Attention).

• Use Case: DOSS is generally considered a monitoring tool suitable for ongoing checks, while the 4AT is a tool best used at specific time points (admission, suspected change). A positive DOSS screen might prompt a 4AT assessment.

• Validation: DOSS has shown variable sensitivity (reported range 25%-97%) and good specificity (89%-98%) in reviews. The 4AT demonstrates consistent pooled sensitivity and specificity around 88% across a much larger number of validation studies (>33 vs fewer reported for DOSS).

• Time/Training: Both are relatively brief. 4AT requires no specific training. DOSS, being observational, is also generally used without extensive formal training.

• Summary: DOSS is a useful nursing observation tool for ongoing monitoring. The 4AT provides a more comprehensive episodic assessment combining observation and cognitive testing, backed by a larger validation evidence base.

The bCAM is, as the name suggests, a shortened assessment based on the CAM algorithm, designed for faster use (< 2 minutes).

• Framework: bCAM uses the CAM algorithm (requiring Feature 1: Acute Change/Fluctuation and Feature 2: Inattention, plus either Feature 3: Altered LoC or Feature 4: Disorganized Thinking). It uses specific tests for inattention.

• Time: Both 4AT and bCAM are designed to be rapid (<2 minutes).

• Validation: bCAM has shown good sensitivity (78%-84%) and very high specificity (96%-97%) in ED validation studies. The 4AT has demonstrated sensitivity and specificity around 88% in pooled analyses across many settings, supported by a larger body of evidence (>33 studies).

• Training: 4AT requires no specific training. While bCAM is designed to be brief, effective use of CAM-based tools often benefits from training on assessing the core features.

• Summary: bCAM offers a quick, CAM-based assessment with high specificity. The 4AT provides a similarly rapid assessment with robust validation across more studies and settings.

• Both tools offer built-in cognitive testing, though the 4AT offers a scoring range with three categories of outcomes and the bCAM gives a binary outcome.

The UB-CAM uses a two-step, CAM-based approach using the UB-2 and the 3D-CAM, aimed at cutting down the time taken for a standard CAM.

• Process: It starts with the UB-2 screen (Months Backwards + Day of the Week). If negative, delirium is considered ruled out. If positive, further 3D-CAM items are administered using a skip pattern (total time ~1.5 minutes). The 4AT is a single-step assessment.

• Time: The UB-CAM process varies according to the results of the UB-2 assessment; overall the time taken between the 4AT and UB-CAM is similar.

• Validation: The initial UB-2 screen has high sensitivity (82-88%) but lower specificity. The full two-step UB-CAM protocol showed lower sensitivity (63-65%) but good specificity (>90%) in one implementation study compared to expert assessment. This sensitivity is lower than the 4AT's pooled sensitivity (~88%).

• Training: UB-CAM use requires training. The 4AT requires no specific training.

• Summary: UB-CAM offers a CAM-based protocol that is faster than the standard CAM. The 4AT is a simple, single-step assessment with higher reported sensitivity in pooled analyses, requires no training, and has a much broader validation base.

The 3D-CAM is a structured interview that operationalizes the CAM diagnostic algorithm, with a median completion time of 3 minutes.

• Time: 3D-CAM takes slightly longer than the 4AT (<2 minutes vs 3 minutes).

• Training: 3D-CAM involves specific training for administration. 4AT requires no specific training.

• Framework: 3D-CAM follows the CAM algorithm rigorously using 20 defined items. 4AT uses its 4 items to generate a score indicative of delirium likelihood.

• Validation: 3D-CAM showed excellent sensitivity (95%) and specificity (94%) in its main validation study. A direct comparison in the PACU setting found 3D-CAM had higher sensitivity (100%) than the 4AT (93%), though both performed well. However, the 4AT has been validated in more studies (>33) across a wider range of clinical settings than the 3D-CAM.

• Summary: 3D-CAM is a well-validated, structured CAM-based tool with high accuracy, but it takes longer and requires training. The 4AT offers comparable robust performance with advantages in speed, simplicity (no training needed), and a broader evidence base across diverse settings.

The SQiD ("Is this patient more confused than before?") is a very simple, single-item case-finding question directed to an informant (staff, family).

• Purpose: SQiD serves as an initial rapid alert or component of monitoring, not a standalone delirium assessment. A positive SQiD would typically trigger a more comprehensive assessment, often using the 4AT. The 4AT itself incorporates this concept within Item 4 (Acute change).

• Scope: SQiD relies solely on informant report about change in confusion. The 4AT provides a multi-component assessment including alertness observation and direct cognitive testing, in addition to assessing acute/fluctuating change.

• Use: SQiD is used in some UK settings, often alongside the 4AT. It has very limited validation as a standalone diagnostic test.

• Summary: SQiD is a useful, quick informant question to raise suspicion, but it is not a substitute for a validated, multi-component assessment like the 4AT. The 4AT provides a more thorough and validated assessment of the likelihood of delirium.

The 4AT's main advantages over other tools lie in its pragmatism and feasibility for routine clinical use. Key strengths include:

○ Speed and Simplicity: Quick administration (<2 mins) without needing special training makes it easy to integrate into busy workflows.

○ Inclusivity: The ability to score 'untestable' patients ensures assessment completion for everyone, including drowsy or non-communicative individuals.

○World-Leading Formal Validation Data: The 4AT has the largest body of formal validation data of any delirium tool, spanning the widest range of settings.

○ World-Leading Clinical Implementation Data. In addition to leading validation data, the 4AT also has the largest body of published clinical implemenation data of any delirium tool.

○ Guideline Recommended: Endorsement in major clinical guidelines adds credibility.

○ Free and Accessible: No cost, permission or registration barriers facilitate widespread adoption and EHR integration.