Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2017 Nov 22;14(11):1420.
doi: 10.3390/ijerph14111420.

Prediction of Mortality in Patients With Isolated Traumatic Subarachnoid Hemorrhage Using a Decision Tree Classifier: A Retrospective Analysis Based on a Trauma Registry System

Free PMC article

Prediction of Mortality in Patients With Isolated Traumatic Subarachnoid Hemorrhage Using a Decision Tree Classifier: A Retrospective Analysis Based on a Trauma Registry System

Cheng-Shyuan Rau et al. Int J Environ Res Public Health. .
Free PMC article


Background: In contrast to patients with traumatic subarachnoid hemorrhage (tSAH) in the presence of other types of intracranial hemorrhage, the prognosis of patients with isolated tSAH is good. The incidence of mortality in these patients ranges from 0-2.5%. However, few data or predictive models are available for the identification of patients with a high mortality risk. In this study, we aimed to construct a model for mortality prediction using a decision tree (DT) algorithm, along with data obtained from a population-based trauma registry, in a Level 1 trauma center. Methods: Five hundred and forty-five patients with isolated tSAH, including 533 patients who survived and 12 who died, between January 2009 and December 2016, were allocated to training (n = 377) or test (n = 168) sets. Using the data on demographics and injury characteristics, as well as laboratory data of the patients, classification and regression tree (CART) analysis was performed based on the Gini impurity index, using the rpart function in the rpart package in R. Results: In this established DT model, three nodes (head Abbreviated Injury Scale (AIS) score ≤4, creatinine (Cr) <1.4 mg/dL, and age <76 years) were identified as important determinative variables in the prediction of mortality. Of the patients with isolated tSAH, 60% of those with a head AIS >4 died, as did the 57% of those with an AIS score ≤4, but Cr ≥1.4 and age ≥76 years. All patients who did not meet the above-mentioned criteria survived. With all the variables in the model, the DT achieved an accuracy of 97.9% (sensitivity of 90.9% and specificity of 98.1%) and 97.7% (sensitivity of 100% and specificity of 97.7%), for the training set and test set, respectively. Conclusions: The study established a DT model with three nodes (head AIS score ≤4, Cr <1.4, and age <76 years) to predict fatal outcomes in patients with isolated tSAH. The proposed decision-making algorithm may help identify patients with a high risk of mortality.

Keywords: decision tree; mortality; subarachnoid hemorrhage; traumatic brain injury; traumatic subarachnoid hemorrhage.

Conflict of interest statement

The authors declare no conflict of interest.


Figure 1
Figure 1
Illustration of the decision tree (DT) model for mortality of patients with isolated traumatic subarachnoid hemorrhage. The boxes denote the percentage of patients with discriminating variables from classification and regression tree (CART) analysis. Those who died and survived are indicated with the fractional number inside the right and left sides of the boxes, respectively.

Similar articles

See all similar articles

Cited by 4 articles


    1. Servadei F., Murray G.D., Teasdale G.M., Dearden M., Iannotti F., Lapierre F., Maas A.J., Karimi A., Ohman J., Persson L., et al. Traumatic subarachnoid hemorrhage: Demographic and clinical study of 750 patients from the European brain injury consortium survey of head injuries. Neurosurgery. 2002;50:261–267. - PubMed
    1. Holmes J.F., Hendey G.W., Oman J.A., Norton V.C., Lazarenko G., Ross S.E., Hoffman J.R., Mower W.R. Epidemiology of blunt head injury victims undergoing ED cranial computed tomographic scanning. Am. J. Emerg. Med. 2006;24:167–173. doi: 10.1016/j.ajem.2005.08.009. - DOI - PubMed
    1. Choi J.H., Jakob M., Stapf C., Marshall R.S., Hartmann A., Mast H. Multimodal early rehabilitation and predictors of outcome in survivors of severe traumatic brain injury. J. Trauma. 2008;65:1028–1035. doi: 10.1097/TA.0b013e31815eba9b. - DOI - PubMed
    1. Compagnone C., d’Avella D., Servadei F., Angileri F.F., Brambilla G., Conti C., Cristofori L., Delfini R., Denaro L., Ducati A., et al. Patients with moderate head injury: A prospective multicenter study of 315 patients. Neurosurgery. 2009;64:690–696. doi: 10.1227/01.NEU.0000340796.18738.F7. - DOI - PubMed
    1. Armin S.S., Colohan A.R., Zhang J.H. Traumatic subarachnoid hemorrhage: Our current understanding and its evolution over the past half century. Neurol. Res. 2006;28:445–452. doi: 10.1179/016164106X115053. - DOI - PubMed