title: Obesity and the decision tree: predictors of sustained weight loss after bariatric surgery.
abstract: OBJECTIVE
  Bariatric surgery is the only long-lasting effective treatment to reduce body weight in morbid obesity. Previous literature in using data mining techniques to predict weight loss in obese patients who have undergone bariatric surgery is limited. This study used initial evaluations before bariatric surgery and data mining techniques to predict weight outcomes in morbidly obese patients seeking surgical treatment.
  
  
  METHODS
  251 morbidly obese patients undergoing laparoscopic mini-gastric bypass (LMGB) or adjustable gastric banding (LAGB) with complete clinical data at baseline and at two years were enrolled for analysis. Decision Tree, Logistic Regression and Discriminant analysis technologies were used to predict weight loss. Overall classification capability of the designed diagnostic models was evaluated by the misclassification costs.
  
  
  RESULTS
  Two hundred fifty-one patients consisting of 68 men and 183 women was studied; with mean age 33 years. Mean +/- SD weight loss at 2 year was 74.5 +/- 16.4 kg. During two years of follow up, two-hundred and five (81.7%) patients had successful weight reduction while 46 (18.3%) were failed to reduce body weight. Operation methods, alanine transaminase (ALT), aspartate transaminase (AST), white blood cell counts (WBC), insulin and hemoglobin A1c (HbA1c) levels were the predictive factors for successful weight reduction.
  
  
  CONCLUSIONS
  Decision tree model was a better classification models than traditional logistic regression and discriminant analysis in view of predictive accuracies.
authors.affiliation: Department of International Business, Ching-Yun University, Zhongli City, Taiwan. lyc6115@ms61.hinet.net
authors.forename: Yi-Chih
authors.initials: YC
authors.lastname: Lee
authors.forename: Wei-Jei
authors.initials: WJ
authors.lastname: Lee
authors.forename: Yang-Chu
authors.initials: YC
authors.lastname: Lin
authors.forename: Phui-Ly
authors.initials: PL
authors.lastname: Liew
authors.forename: Chia Ko
authors.initials: CK
authors.lastname: Lee
authors.forename: Steven C H
authors.initials: SC
authors.lastname: Lin
authors.forename: Tian-Shyung
authors.initials: TS
authors.lastname: Lee
mesh_terms: D000328:Adult; D050110:Bariatric Surgery; D003663:Decision Trees; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007958:Leukocyte Count; D008111:Liver Function Tests; D016015:Logistic Models; D008297:Male; D009765:Obesity / Q000097:blood / Q000601:surgery*; D011446:Prospective Studies; D016896:Treatment Outcome; D015431:Weight Loss
chemical_list: D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human