title: Classification techniques on computerized systems to predict and/or to detect Apnea: A systematic review.
abstract: OBJECTIVE
  Sleep apnea syndrome (SAS), which can significantly decrease the quality of life is associated with a major risk factor of health implications such as increased cardiovascular disease, sudden death, depression, irritability, hypertension, and learning difficulties. Thus, it is relevant and timely to present a systematic review describing significant applications in the framework of computational intelligence-based SAS, including its performance, beneficial and challenging effects, and modeling for the decision-making on multiple scenarios.
  
  
  METHODS
  This study aims to systematically review the literature on systems for the detection and/or prediction of apnea events using a classification model.
  
  
  RESULTS
  Forty-five included studies revealed a combination of classification techniques for the diagnosis of apnea, such as threshold-based (14.75%) and machine learning (ML) models (85.25%). In addition, the ML models, were clustered in a mind map, include neural networks (44.26%), regression (4.91%), instance-based (11.47%), Bayesian algorithms (1.63%), reinforcement learning (4.91%), dimensionality reduction (8.19%), ensemble learning (6.55%), and decision trees (3.27%).
  
  
  CONCLUSIONS
  A classification model should provide an auto-adaptive and no external-human action dependency. In addition, the accuracy of the classification models is related with the effective features selection. New high-quality studies based on randomized controlled trials and validation of models using a large and multiple sample of data are recommended.
authors.affiliation: Research Units: Instituto de Telecomunicações and ALLab Assisted Living Computing and Telecommunications Laboratory, Department of Informatics, Universidade da Beira Interior, Covilhã, Portugal and Universidade Lusófona de Humanidades e Tecnologias, Lisbon, Portugal. Electronic address: ngpombo@ubi.pt.
authors.forename: Nuno
authors.initials: N
authors.lastname: Pombo
authors.affiliation: Research Units: Instituto de Telecomunicações and ALLab Assisted Living Computing and Telecommunications Laboratory, Department of Informatics, Universidade da Beira Interior, Covilhã, Portugal and Universidade Lusófona de Humanidades e Tecnologias, Lisbon, Portugal. Electronic address: ngarcia@di.ubi.pt.
authors.forename: Nuno
authors.initials: N
authors.lastname: Garcia
authors.affiliation: Research Unit: LAETA/UBI-AEROG, Department of Aerospace Sciences, Universidade da Beira Interior, Covilhã, Portugal. Electronic address: bousson@ubi.pt.
authors.forename: Kouamana
authors.initials: K
authors.lastname: Bousson
mesh_terms: D000465:Algorithms; D003936:Diagnosis, Computer-Assisted; D006801:Humans; D017286:Polysomnography; D012891:Sleep Apnea Syndromes / Q000145:classification / Q000175:diagnosis*
keywords: Classification; Machine learning; Sleep apnea; Systematic review; Threshold-based classification