Narayan's logistic model uses multivariate analysis to predict the probability of poor or good outcome in patients with coma.
Predictor |
Value |
Coefficient |
age in years |
same |
0.061 |
Glasgow Coma Score |
same |
(-0.469) |
pupillary reaction to light |
0 (normal or unilaterally absent) or 1 (bilaterally absent) |
1.545 |
oculocephalic or oculovestibular responses eye movements |
0 (normal) or 1 (impaired or absent on either or both sides) |
0.611 |
surgical mass |
0 (absent) or 1 (present) |
0.765 |
probability of poor outcome=
= (1 / (1 + (e ^ ((-1)*((sums of (value * coefficient)) - 0.674)))))
probability of good outcome = 1 - (probability of poor outcome)
where:
• 0.674 is the line intercept
• Poor outcome indicates severe disability, vegetative state or death.
• Good outcome indicates good recovery or moderate disability.
Limitations:
• Prediction is most accurate for patients at the extremes
• Prediction is least accurate for patients in the mid-range
• Patients with gunshot wounds to the head were excluded
Purpose: To predict the probability of outcome in a patient with coma using the Narayan model.
Specialty: Sports Medicine & Rehabilitation, Neurology
Objective: severity, prognosis, stage
ICD-10: R40.2,