A filter approach for feature selection in classification: application to automatic atrial fibrillation detection in electrocardiogram recordings

Pierre Michel (1) , Nicolas Ngo (2) , Jean-François Pons (3) , Stéphane Delliaux (4) , Roch Giorgi (2)

1 AMSE - Aix-Marseille Sciences Economiques
2 SESSTIM - U1252 INSERM - Aix Marseille Univ - UMR 259 IRD - Sciences Economiques et Sociales de la Santé & Traitement de l'Information Médicale
3 WitMonki
4 C2VN - Centre recherche en CardioVasculaire et Nutrition = Center for CardioVascular and Nutrition research

Background: In high-dimensional data analysis, the complexity of predictive models can be reduced by selecting the most relevant features, which is crucial to reduce data noise and increase model accuracy and interpretability. Thus, in the field of clinical decision making, only the most relevant features from a set of medical descriptors should be considered when determining whether a patient is healthy or not. This statistical approach known as feature selection can be performed through regression or classification, in a supervised or unsupervised manner. Several feature selection approaches using different mathematical concepts have been described in the literature. In the field of classification, a new approach has recently been proposed that uses the γ-metric, an index measuring separability between different classes in heart rhythm characterization. The present study proposes a filter approach for feature selection in classification using this γ-metric, and evaluates its application to automatic atrial fibrillation detection. Methods: The stability and prediction performance of the γ-metric feature selection approach was evaluated using the support vector machine model on two heart rhythm datasets, one extracted from the PhysioNet database and the other from the database of Marseille University Hospital Center, France (Timone Hospital). Both datasets contained electrocardiogram recordings grouped into two classes: normal sinus rhythm and atrial fibrillation. The performance of this feature selection approach was compared to that of three other approaches, with the first two based on the Random Forest technique and the other on receiver operating characteristic curve analysis. Results: The γ-metric approach showed satisfactory results, especially for models with a smaller number of features. For the training dataset, all prediction indicators were higher for our approach (accuracy greater than 99% for models with 5 to 17 features), as was stability (greater than 0.925 regardless of the number of features included in the model). For the validation dataset, the features selected with the y-metric approach differed from those selected with the other approaches; sensitivity was higher for our approach, but other indicators were similar. Conclusion: This filter approach for feature selection in classification opens up new methodological avenues for atrial fibrillation detection using short electrocardiogram recordings.

Mots clés: y-metric; atrial fibrillation detection; classification; clinical decision making; feature selection; machine learning; γ-metric; Machine learning; Feature selection; Classification; Clinical decision making; Atrial fibrillation detection

Domaines: Economies et finances

Pierre Michel, Nicolas Ngo, Jean-François Pons, Stéphane Delliaux, Roch Giorgi. A filter approach for feature selection in classification: application to automatic atrial fibrillation detection in electrocardiogram recordings. BMC Medical Informatics and Decision Making, 2021, 21 (S4), ⟨10.1186/s12911-021-01427-8⟩. ⟨hal-03222439⟩