Open Access Research article

Computational classifiers for predicting the short-term course of Multiple sclerosis

Bartolome Bejarano1, Mariangela Bianco2, Dolores Gonzalez-Moron1, Jorge Sepulcre1, Joaquin Goñi1, Juan Arcocha1, Oscar Soto1, Ubaldo Del Carro2, Giancarlo Comi2, Letizia Leocani2 and Pablo Villoslada13*

Author Affiliations

1 Department of Neuroscience, CIMA-University of Navarra, Pamplona, Spain

2 Department of Neurology, Clinical Neurophysiology and Neurorehabilitation, University Vita-Salute, Scientific Institute Hospital San Raffaele, Milan, Italy

3 Center for Neuroimmunology, IDIBAPS-Hospital Clinic, Barcelona, Spain

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BMC Neurology 2011, 11:67  doi:10.1186/1471-2377-11-67

Published: 7 June 2011

Abstract

Background

The aim of this study was to assess the diagnostic accuracy (sensitivity and specificity) of clinical, imaging and motor evoked potentials (MEP) for predicting the short-term prognosis of multiple sclerosis (MS).

Methods

We obtained clinical data, MRI and MEP from a prospective cohort of 51 patients and 20 matched controls followed for two years. Clinical end-points recorded were: 1) expanded disability status scale (EDSS), 2) disability progression, and 3) new relapses. We constructed computational classifiers (Bayesian, random decision-trees, simple logistic-linear regression-and neural networks) and calculated their accuracy by means of a 10-fold cross-validation method. We also validated our findings with a second cohort of 96 MS patients from a second center.

Results

We found that disability at baseline, grey matter volume and MEP were the variables that better correlated with clinical end-points, although their diagnostic accuracy was low. However, classifiers combining the most informative variables, namely baseline disability (EDSS), MRI lesion load and central motor conduction time (CMCT), were much more accurate in predicting future disability. Using the most informative variables (especially EDSS and CMCT) we developed a neural network (NNet) that attained a good performance for predicting the EDSS change. The predictive ability of the neural network was validated in an independent cohort obtaining similar accuracy (80%) for predicting the change in the EDSS two years later.

Conclusions

The usefulness of clinical variables for predicting the course of MS on an individual basis is limited, despite being associated with the disease course. By training a NNet with the most informative variables we achieved a good accuracy for predicting short-term disability.