title: [Classification of dengue hemorrhagic fever using decision trees in the early phase of the disease].
abstract: BACKGROUND
  dengue is a viral disease with endemic behavior. At the beginning of the illness it is not possible to know which patients will have an unfavorable evolution and develop a severe form of dengue. However, some warning symptoms and signs may be present.
  
  
  OBJECTIVE
  to apply decision tree techniques to the exploration of signs of severity in the early phase of the illness.
  
  
  METHODS
  the study sample was made up of 230 patients admitted with dengue to "Pedro Kouri" Institute of Tropical Medicine in 2001. The variables considered for the classification were the signs, symptoms and laboratory exams on the third day of evolution of the illness. The algorithm of classification and regression trees using the Gini's index was applied. Different loss matrices to improve the sensitivity were considered.
  
  
  RESULTS
  the algorithm CART, corresponding to the best loss, had a sensitivity of 98,68% and global error of 0,36. Without considering loss, it obtained its sensitivity reached 74% with an error of 0,25. In both cases, the most important variables were platelets and hemoglobin.
  
  
  CONCLUSIONS
  the study submitted rules of decision with high sensitivity and negative predictive value of utility in the clinical practice. The laboratory variables resulted more important from the informational viewpoint than the clinical ones to discriminate clinical forms of dengue.
authors: Instituto de Medicina Tropical Pedro Kouri, La Habana, Cuba. beatrizv@ipk.sld.cu
authors: Beatriz
authors: B
authors: Vega Riverón
authors: C Lizet
authors: CL
authors: Sánchez Valdés
authors: C José
authors: CJ
authors: Cortiñas Abrahantes
authors: Osvaldo
authors: O
authors: Castro Peraza
authors: C Daniel
authors: CD
authors: González Rubio
authors: Marta
authors: M
authors: Castro Peraza
mesh_terms: D003663:Decision Trees; D018450:Disease Progression; D042241:Early Diagnosis; D006801:Humans; D019595:Severe Dengue / Q000145:classification*