title: VALORATE: fast and accurate log-rank test in balanced and unbalanced comparisons of survival curves and cancer genomics.
abstract: CONCLUSIONS
  The association of genomic alterations to outcomes in cancer is affected by a problem of unbalanced groups generated by the low frequency of alterations. For this, an R package (VALORATE) that estimates the null distribution and the P -value of the log-rank based on a recent reformulation is presented. For a given number of alterations that define the size of survival groups, the log-rank density is estimated by a weighted sum of conditional distributions depending on a co-occurrence term of mutations and events. The estimations are accurately accelerated by sampling across co-occurrences allowing the analysis of large genomic datasets in few minutes. In conclusion, the proposed VALORATE R package is a valuable tool for survival analysis.
  
  
  METHODS
  The R package is available in CRAN at https://cran.r-project.org and in http://bioinformatica.mty.itesm.mx/valorateR .
  
  
  BACKGROUND
  vtrevino@itesm.mx.
  
  
  BACKGROUND
  Supplementary data are available at Bioinformatics online.
authors.affiliation: Cátedra de Bioinformática, Escuela de Medicina, Tecnológico de Monterrey, Monterrey N.L., México.
authors.forename: Victor
authors.initials: V
authors.lastname: Treviño
authors.affiliation: Cátedra de Bioinformática, Escuela de Medicina, Tecnológico de Monterrey, Monterrey N.L., México.
authors.forename: Jose
authors.initials: J
authors.lastname: Tamez-Pena
mesh_terms: D023281:Genomics / Q000379:methods*; D006801:Humans; D009154:Mutation; D009369:Neoplasms / Q000235:genetics*; D012984:Software; D016019:Survival Analysis