Article

Prediction of periventricular leukomalacia. Part II: Selection of hemodynamic features using computational intelligence.

Department of Mechanical Engineering, Villanova University, PA 19085, USA.
Artificial intelligence in medicine (impact factor: 1.65). 02/2009; 46(3):217-31. DOI:10.1016/j.artmed.2008.12.004
Source: PubMed

ABSTRACT The objective of Part II is to analyze the dataset of extracted hemodynamic features (Case 3 of Part I) through computational intelligence (CI) techniques for identification of potential prognostic factors for periventricular leukomalacia (PVL) occurrence in neonates with congenital heart disease.
The extracted features (Case 3 dataset of Part I) were used as inputs to CI based classifiers, namely, multi-layer perceptron (MLP) and probabilistic neural network (PNN) in combination with genetic algorithms (GA) for selection of the most suitable features predicting the occurrence of PVL. The selected features were next used as inputs to a decision tree (DT) algorithm for generating easily interpretable rules of PVL prediction.
Prediction performance for two CI based classifiers, MLP and PNN coupled with GA are presented for different number of selected features. The best prediction performances were achieved with 6 and 7 selected features. The prediction success was 100% in training and the best ranges of sensitivity (SN), specificity (SP) and accuracy (AC) in test were 60-73%, 74-84% and 71-74%, respectively. The identified features when used with the DT algorithm gave best SN, SP and AC in the ranges of 87-90% in training and 80-87%, 74-79% and 79-82% in test. Among the variables selected in CI, systolic and diastolic blood pressures, and pCO(2) figured prominently similar to Part I. Decision tree based rules for prediction of PVL occurrence were obtained using the CI selected features.
The proposed approach combines the generalization capability of CI based feature selection approach and generation of easily interpretable classification rules of the decision tree. The combination of CI techniques with DT gave substantially better test prediction performance than using CI and DT separately.

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Keywords

Case 3
 
Case 3 dataset
 
CI techniques
 
congenital heart disease
 
decision tree
 
diastolic blood pressures
 
feature selection approach
 
genetic algorithms
 
Part I. Decision tree
 
Part II
 
periventricular leukomalacia
 
potential prognostic factors
 
Prediction performance
 
prediction performances
 
prediction success
 
probabilistic neural network
 
proposed approach
 
PVL occurrence
 
PVL prediction
 
specificity