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New Orleans Head CT Rule: the seven findings and how they combine

The New Orleans Head CT Rule checks seven yes/no findings after a minor head injury: headache, vomiting, age over 60, drug or alcohol intoxication, a deficit in short-term memory, physical evidence of trauma above the collarbones, and a seizure. Magent's calculator returns a true/false result that's true when any one of the seven is present and false when none is.

This page doesn't give disposition advice. It shows how the findings combine. What to do with the result depends on the clinical context.

Not a medical device. Not a diagnosis or dosing recommendation.

Use this calculator via API

What is the New Orleans Head CT Rule?

The rule comes from a 2000 paper by Haydel, Preston, Mills and colleagues in the New England Journal of Medicine, titled Indications for computed tomography in patients with minor head injury. It's also called the New Orleans criteria, the Charity Head CT Rule, or the Haydel rule. Magent's record describes the published rule as for minor head injury with a Glasgow Coma Scale (GCS) of 15.

It's a set of yes/no findings, not a points score.

The New Orleans rule logic

result = headache
      OR vomiting
      OR age > 60
      OR drug or alcohol intoxication
      OR short-term memory deficit
      OR trauma above the clavicles
      OR seizure

Exact expression the calculator uses:

ct indicated if any of headache, vomiting, age > 60, drug_or_alcohol_intoxication, short_term_memory_deficit, trauma_above_clavicles, or seizure

What each finding means

FindingWhat counts
HeadacheHeadache, as assigned by the user
VomitingVomiting, as assigned by the user
AgeOlder than 60. Age 60 doesn't count; 61 does.
Drug or alcohol intoxicationIntoxication, as assigned by the user
Short-term memory deficitA deficit in short-term memory (anterograde amnesia)
Trauma above the claviclesPhysical evidence of injury above the collarbones
SeizureA seizure, as assigned by the user

How the rule works

  1. Check the six clinical findings. Headache, vomiting, intoxication, a short-term memory deficit, trauma above the clavicles and a seizure are each true or false.
  2. Check age. Older than 60 counts as a finding.
  3. Combine. If any one finding is present, the result is true. If none is, the result is false.

Inputs come from the user

The record says the person using the calculator assigns each clinical finding. Magent's calculator doesn't examine anyone, and it doesn't take a GCS. It takes age from 18 to 120 and returns the true/false result (in a field named ct_indicated), the age it used and a line for each finding.

Worked examples

These are the worked examples in Magent's record for the calculator.

Example 1: age 40, nothing present

  1. Age 40 isn't over 60.
  2. All six clinical findings are false.
  3. Result: false.

Example 2: age 61, nothing else

  1. Age 61 is over 60. Age 60 wouldn't count.
  2. Result: true.

Example 3: headache alone

  1. Age 40 doesn't meet the age finding.
  2. Headache is present.
  3. Result: true.

Values at the boundaries

All are Magent's expected values for the calculator, starting from age 40 with nothing present.

  • Age 60 → false; age 61 → true.
  • Vomiting, intoxication, a short-term memory deficit, trauma above the clavicles or a seizure on its own → true.

History of the New Orleans Head CT Rule

The rule comes from Haydel MJ, Preston CA, Mills TJ and colleagues, Indications for computed tomography in patients with minor head injury, New England Journal of Medicine, 2000 (volume 343, issue 2, pages 100–105).

When it's used

Magent's record describes the published rule as for minor head injury with a GCS of 15.

Where it's used

Every input is a finding at the bedside or the person's age.

Who uses it

The person using the calculator assigns each finding. The calculator combines them.

Limits of the calculation

  • It combines seven yes/no findings. It doesn't examine anyone and doesn't diagnose a brain injury.
  • It's the Haydel 2000 New Orleans (Charity) Head CT Rule. It isn't the Canadian CT Head Rule, it isn't PECARN, and it isn't a pediatric head-CT rule.
  • It doesn't take a GCS. The published rule is for a GCS of 15.
  • Age must be 18 to 120.
  • This page doesn't say what to do with the result.

Clinical decisions belong to a qualified clinician who knows the patient.

  • Canadian CT Head Rule is a separate head-injury rule with its own findings, split into high-risk and medium-risk groups.
  • NEXUS criteria are about the cervical spine, not the head.

Glossary

  • CT: computed tomography, a cross-sectional X-ray scan.
  • Clavicles: the collarbones.
  • Anterograde amnesia: trouble forming new memories after an event.
  • Glasgow Coma Scale (GCS): a total for eye, verbal and motor responses.

Common mistakes

  • Counting age 60. The age finding is older than 60.
  • Expecting a score. The rule gives a true/false result, not points.
  • Using it for children. The calculator accepts ages 18 to 120.
  • Mixing it up with the Canadian CT Head Rule. They're separate rules with different findings.

Source

Haydel MJ, Preston CA, Mills TJ, Luber S, Blaudeau E, DeBlieux PM. Indications for computed tomography in patients with minor head injury. N Engl J Med. 2000;343(2):100-105. DOI: 10.1056/NEJM200007133430204

Frequently asked questions

What are the New Orleans criteria?

Headache, vomiting, age over 60, drug or alcohol intoxication, a short-term memory deficit, physical evidence of trauma above the clavicles, and a seizure.

Does the New Orleans rule apply to children?

The calculator accepts ages 18 to 120.

Does age 60 count?

No. The age finding is older than 60, so 61 counts and 60 doesn't.

Is the New Orleans rule a score?

No. It's a set of yes/no findings. The result is true if any one is present.

Who developed the New Orleans Head CT Rule?

Haydel and colleagues, in a 2000 paper in the New England Journal of Medicine.