A Support Vectors Classifier Approach to Predicting the Risk of Progression of Adolescent Idiopathic Scoliosis
A support vector classifier (SVC) approach was employed in predicting the risk of progression of adolescent idiopathic scoliosis (AIS), a condition that causes visible trunk asymmetries. As the aetiology of AIS is unknown, its risk of progression can only be predicted from measured indicators. Previous studies suggest that individual indicators of AIS do not reliably predict its risk of progression. Complex indicators with better predictive values have been developed but are unsuitable for clinical use as obtaining their values is often onerous, involving much skill and repeated measurements taken over time. Based on the hypothesis that combining common indicators of AIS using an SVC approach would produce better prediction results more quickly, we conducted a study using three datasets comprising a total of 44 moderate AIS patients (30 observed, 14 treated with brace). Of the 44 patients, 13 progressed less than 5° and 31 progressed more than 5°. One dataset comprised all the patients. A second dataset comprised all the observed patients and a third comprised all the brace-treated patients. Twenty-one radiographic and clinical indicators were obtained for each patient. The result of testing on the three datasets showed that the system achieved 100% accuracy in training and 65%-80% accuracy in testing. It outperformed a "statistically equivalent" logistic regression model and a stepwise linear regression model on the said datasets. It took less than 20 min per patient to measure the indicators, input their values into the system, and produce the needed results, making the system viable for use in a clinical environment.
Available from: Christophoros Nikou
- "In the last decade, SVM learning has found a wide range of applications , including image segmentation  and classification , object recognition , image fusion , and stereo correspondence . More recently, SVMs have been employed in several applications in biomedicine: gait degeneration due to age , EEG signal classification , brain computer interfacing (BCI) , , analysis and prediction of scoliosis , , electrogastrogram analysis , and color Doppler echocardiography . Relevant studies involving SVM and heart rate time series are the Hermite characterization of QRS complex , where a heartbeat is characterized as normal or abnormal and the detection of risky situations for fetal assessment . "
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