impact_head_injury_prognosis: IMPACT Score for Head Injury Outcomes

In cliot: Clinical Indices and Outcomes Tools

IMPACT Score for Head Injury Outcomes

Description

Calculates the predicted 6-month probability of mortality and unfavorable outcome (Death, Vegetative State, or Severe Disability) in patients with moderate to severe Traumatic Brain Injury (TBI). This function implements the Extended Model (Clinical + CT findings) and optionally the Lab Model if glucose and hemoglobin are provided.

Usage

impact_head_injury_prognosis(age, motor_score, pupils_reactive, ct_marshall_class,
                             tsah_present, epidural_mass_present,
                             glucose_mg_dl = NULL, hemoglobin_g_dl = NULL)

Arguments

age	Numeric. Patient age in years.
motor_score	Numeric (1-6). Glasgow Coma Scale Motor Score. 1: None. 2: Extension. 3: Flexion (Abnormal). 4: Withdrawal. 5: Localizes. 6: Obeys.
pupils_reactive	Numeric (0, 1, or 2). Number of pupils reactive to light.
ct_marshall_class	Numeric (1-6). Marshall CT Classification. 1: Diffuse Injury I (No visible pathology). 2: Diffuse Injury II (Cisterns present, shift < 5mm, no high density > 25cc). 3: Diffuse Injury III (Cisterns compressed/absent, shift < 5mm, no high density > 25cc). 4: Diffuse Injury IV (Midline shift > 5mm, no high density > 25cc). 5: Evacuated Mass Lesion V. 6: Non-Evacuated Mass Lesion VI (> 25cc, not evacuated).
tsah_present	Numeric (0 or 1). Traumatic Subarachnoid Hemorrhage on CT? (1 = Yes).
epidural_mass_present	Numeric (0 or 1). Epidural Hematoma on CT? (1 = Yes). Note: Epidural hematomas are often associated with better outcomes compared to other lesions in this model.
glucose_mg_dl	Numeric (Optional). Admission serum glucose in mg/dL.
hemoglobin_g_dl	Numeric (Optional). Admission hemoglobin in g/dL.

Value

A list containing:

Predicted_6mo_Mortality	The estimated probability of death at 6 months.
Predicted_6mo_Unfavorable_Outcome	The estimated probability of an unfavorable outcome (GOSE 1-4) at 6 months.
Definitions	Definitions of outcomes.

References

Steyerberg EW, Mushkudiani N, Perel P, et al. Predicting outcome after traumatic brain injury: development and international validation of prognostic scores based on admission characteristics. PLoS Med. 2008;5(8):e165. doi:10.1371/journal.pmed.0050165

Examples

# Example 1: Poor Prognosis
# 70yo, Motor 2, 0 Pupils, Marshall VI (Non-evac mass), tSAH, No Epidural
impact_head_injury_prognosis(70, 2, 0, 6, 1, 0)

# Example 2: Better Prognosis
# 25yo, Motor 5, 2 Pupils, Marshall II, No tSAH, Epidural present
impact_head_injury_prognosis(25, 5, 2, 2, 0, 1)

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