PMID- 24001924 OWN - NLM STAT- MEDLINE DCOM- 20140611 LR - 20131018 IS - 1872-7565 (Electronic) IS - 0169-2607 (Linking) VI - 112 IP - 3 DP - 2013 Dec TI - An improved method of early diagnosis of smoking-induced respiratory changes using machine learning algorithms. PG - 441-54 LID - S0169-2607(13)00280-0 [pii] LID - 10.1016/j.cmpb.2013.08.004 [doi] AB - The purpose of this study was to develop an automatic classifier to increase the accuracy of the forced oscillation technique (FOT) for diagnosing early respiratory abnormalities in smoking patients. The data consisted of FOT parameters obtained from 56 volunteers, 28 healthy and 28 smokers with low tobacco consumption. Many supervised learning techniques were investigated, including logistic linear classifiers, k nearest neighbor (KNN), neural networks and support vector machines (SVM). To evaluate performance, the ROC curve of the most accurate parameter was established as baseline. To determine the best input features and classifier parameters, we used genetic algorithms and a 10-fold cross-validation using the average area under the ROC curve (AUC). In the first experiment, the original FOT parameters were used as input. We observed a significant improvement in accuracy (KNN=0.89 and SVM=0.87) compared with the baseline (0.77). The second experiment performed a feature selection on the original FOT parameters. This selection did not cause any significant improvement in accuracy, but it was useful in identifying more adequate FOT parameters. In the third experiment, we performed a feature selection on the cross products of the FOT parameters. This selection resulted in a further increase in AUC (KNN=SVM=0.91), which allows for high diagnostic accuracy. In conclusion, machine learning classifiers can help identify early smoking-induced respiratory alterations. The use of FOT cross products and the search for the best features and classifier parameters can markedly improve the performance of machine learning classifiers. CI - Copyright (c) 2013 Elsevier Ireland Ltd. All rights reserved. FAU - Amaral, Jorge L M AU - Amaral JL AD - Department of Electronics and Telecommunications Engineering, State University of Rio de Janeiro, Rio de Janeiro, Brazil. FAU - Lopes, Agnaldo J AU - Lopes AJ FAU - Jansen, Jose M AU - Jansen JM FAU - Faria, Alvaro C D AU - Faria AC FAU - Melo, Pedro L AU - Melo PL LA - eng PT - Journal Article DEP - 20130817 PL - Ireland TA - Comput Methods Programs Biomed JT - Computer methods and programs in biomedicine JID - 8506513 SB - IM MH - *Algorithms MH - *Artificial Intelligence MH - *Early Diagnosis MH - Humans MH - ROC Curve MH - Respiratory System/*physiopathology MH - Smoking/*physiopathology OTO - NOTNLM OT - Artificial intelligence OT - Chronic obstructive pulmonary disease OT - Clinical decision support OT - Early diagnosis OT - Forced oscillation technique OT - Smoking EDAT- 2013/09/05 06:00 MHDA- 2014/06/12 06:00 CRDT- 2013/09/05 06:00 PHST- 2013/01/17 00:00 [received] PHST- 2013/07/23 00:00 [revised] PHST- 2013/08/07 00:00 [accepted] PHST- 2013/09/05 06:00 [entrez] PHST- 2013/09/05 06:00 [pubmed] PHST- 2014/06/12 06:00 [medline] AID - S0169-2607(13)00280-0 [pii] AID - 10.1016/j.cmpb.2013.08.004 [doi] PST - ppublish SO - Comput Methods Programs Biomed. 2013 Dec;112(3):441-54. doi: 10.1016/j.cmpb.2013.08.004. Epub 2013 Aug 17.