nexus_head_ct_rule: NEXUS Head CT Decision Instrument

In cliot: Clinical Indices and Outcomes Tools

NEXUS Head CT Decision Instrument

Description

Calculates the NEXUS Head CT result to determine the need for head CT imaging in blunt head trauma patients. If any one of the eight criteria is present, the patient is not considered low risk, and imaging is indicated.

Usage

nexus_head_ct_rule(age_ge_65, skull_fracture_evidence, scalp_hematoma,
                   neurologic_deficit, altered_alertness, abnormal_behavior,
                   coagulopathy, persistent_vomiting)

Arguments

age_ge_65	Numeric (0 or 1). Is the patient 65 years of age or older? (1 = Yes).
skull_fracture_evidence	Numeric (0 or 1). Evidence of significant skull fracture? (1 = Yes).
scalp_hematoma	Numeric (0 or 1). Scalp hematoma present? (1 = Yes).
neurologic_deficit	Numeric (0 or 1). Neurologic deficit present? (1 = Yes).
altered_alertness	Numeric (0 or 1). Altered level of alertness? (1 = Yes).
abnormal_behavior	Numeric (0 or 1). Abnormal behavior present? (1 = Yes).
coagulopathy	Numeric (0 or 1). Coagulopathy present? (1 = Yes).
persistent_vomiting	Numeric (0 or 1). Persistent vomiting? (1 = Yes).

Value

A list containing:

Result	Recommendation regarding the need for Head CT ("Indicated" or "Not Indicated").
Inputs	A summary of the criteria evaluated.

References

Mower WR, Hoffman JR, Herbert M, et al. Developing a decision instrument to guide computed tomographic imaging of blunt head injury patients. J Trauma. 2005;59(4):954-959. doi:10.1097/01.ta.0000187813.79047.42

Examples

# Example 1: Low Risk
# No criteria present
nexus_head_ct_rule(0, 0, 0, 0, 0, 0, 0, 0)

# Example 2: Indicated (Age)
# 70yo, no other findings
nexus_head_ct_rule(1, 0, 0, 0, 0, 0, 0, 0)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.