🧠 Master the FOUR Score

🔍 What is the FOUR Score?

The FOUR Score (Full Outline of UnResponsiveness) is a clinical grading scale used to assess the depth of consciousness in patients with altered mental status. It was developed in 2005 by Dr. Eelco F.M. Wijdicks and colleagues at the Mayo Clinic to overcome the limitations of the Glasgow Coma Scale (GCS), especially in intubated patients.

Unlike the GCS, the FOUR Score does not rely on verbal response, making it reliable for intubated, aphasic, or sedated patients. It also evaluates brainstem function, which is critical for detecting herniation or brain death.

📚 Scientific Foundations

The FOUR Score was validated in a landmark study published in Neurocritical Care (2005) by Wijdicks et al. The study involved 120 critically ill patients and demonstrated excellent inter‑rater reliability (κ = 0.86) and superior prognostic value for mortality compared to the GCS.

The scale is now recommended by the Neurocritical Care Society and is widely used in clinical trials, stroke units, and trauma centers. Its main advantages over the GCS are:

• No verbal component – usable in intubated patients.
• Brainstem reflexes – early detection of midbrain or pontine dysfunction.
• Respiration patterns – differentiates Cheyne‑Stokes from irregular breathing.
• Better discrimination at the lower end of the scale (GCS 3 can be FOUR 1–8).

🧩 The 4 Components

Each of the four components is scored from 0 to 4, with specific clinical criteria. Here are the criteria presented as stacked cards for easy memorisation.

👁️ Eye Response (E)

💪 Motor Response (M)

🧠 Brainstem Reflexes (BS)

🫁 Respiration (R)

⚙️ Formula & Calculation

The FOUR Score is calculated by simple addition of the four component scores:

There is no weighted coefficient – each component contributes equally. The total score is a direct reflection of the patient’s neurological status. A higher score indicates better function.

📊 Interpretation & Thresholds

The FOUR Score is interpreted using five clinical categories, based on the original thresholds defined by Wijdicks et al. (2005).

Clinical relevance: The FOUR Score has been shown to correlate with 30‑day mortality and functional outcome after cardiac arrest, traumatic brain injury, and stroke. A score ≤ 8 indicates poor prognosis and warrants aggressive neuroprotective measures.

🖥️ How to Use the Application

Our interactive FOUR Score application is designed for rapid clinical use in emergency and ICU settings. Follow these steps:

Detailed Walkthrough

1. Tab 1 – Eye & Motor: Click on the card that best matches the patient’s eye opening and motor response. The card will highlight in blue. Both sections must be completed to proceed.
2. Tab 2 – Brainstem & Respiration: Similarly, select the appropriate reflexes and breathing pattern. The application will guide you with validation alerts.
3. Tab 3 – Context & Calculation: Select the mechanism (e.g., trauma, stroke) from the dropdown — this is mandatory. You may also add optional notes on confounding factors or associated neurological signs.
4. Calculate: Press the “Calculate Score FOUR” button. The result card will appear with:
   • Total score (0–16) in large type.
   • Colour‑coded background (green → red) matching severity.
   • Interpretation text (e.g., “Severe coma”).
   • Sub‑scores for E, M, BS, and R.
5. History & PDF: Each calculation is saved in the history table. You can delete individual entries or clear the entire history. Once a result is displayed, the “Export PDF” button generates a comprehensive clinical report.
6. New Evaluation: The “New Evaluation” button resets all scores and context without erasing the history, allowing you to start a new patient assessment quickly.

⚠️ Clinical Tips & Pitfalls

✅ Best Practices

• Standardise the examination: Always test pupillary light reflex with a bright light, corneal reflex with a cotton wisp, and cough reflex via tracheal suctioning.
• Document sedation: If the patient is sedated or curarised, note this in the “Confounding factors” field — the score may not reflect the true neurological state.
• Use with other tools: The FOUR Score is not a replacement for a full neurological examination; combine it with pupilometry, imaging, and EEG.
• Repeat frequently: In dynamic conditions (e.g., intracranial haemorrhage), repeated scoring helps track deterioration or improvement.

❌ Common Mistakes

• Confusing motor localisation with flexion: Localisation requires the hand to cross the chin; flexion is a stereotyped limb movement.
• Misinterpreting myoclonus: Generalised myoclonus after cardiac arrest is scored as 0 (motor) — it is not a purposeful response.
• Overlooking the cough reflex: For BS score 0, the cough reflex must be tested via suctioning — it is frequently omitted.
• Using it as a death certificate: A score of 0 is highly suggestive but not diagnostic of brain death; confirmatory tests are mandatory.

📖 References

• Wijdicks EFM, Bamlet WR, Maramattom BV, Manno EM, McClelland RL. “Validation of a new coma scale: The FOUR Score.” Neurocritical Care. 2005;2(3):252-258. DOI: 10.1385/NCC:2:3:252
• Wijdicks EFM. “The FOUR Score: A new coma scale for the intensive care unit.” Practical Neurology. 2006;6(1):42-47.
• Neurocritical Care Society. “Guidelines for the management of severe traumatic brain injury.” Neurocritical Care. 2017;27(Suppl 1):1-10.