title: Confidence limit calculation for antidotal potency ratio derived from lethal dose 50.
abstract: OBJECTIVE
  To describe confidence interval calculation for antidotal potency ratios using bootstrap method.
  
  
  METHODS
  We can easily adapt the nonparametric bootstrap method which was invented by Efron to construct confidence intervals in such situations like this. The bootstrap method is a resampling method in which the bootstrap samples are obtained by resampling from the original sample.
  
  
  RESULTS
  The described confidence interval calculation using bootstrap method does not require the sampling distribution antidotal potency ratio. This can serve as a substantial help for toxicologists, who are directed to employ the Dixon up-and-down method with the application of lower number of animals to determine lethal dose 50 values for characterizing the investigated toxic molecules and eventually for characterizing the antidotal protections by the test antidotal systems.
  
  
  CONCLUSIONS
  The described method can serve as a useful tool in various other applications. Simplicity of the method makes it easier to do the calculation using most of the programming software packages.
authors.affiliation: Ananda Manage, Department of Mathematics and Statistics, Sam Houston State University, Huntsville, TX 77341, United States.
authors.forename: Ananda
authors.initials: A
authors.lastname: Manage
authors.affiliation: Ananda Manage, Department of Mathematics and Statistics, Sam Houston State University, Huntsville, TX 77341, United States.
authors.forename: Ilona
authors.initials: I
authors.lastname: Petrikovics
keywords: Confidence limit; Potency ratio, Bootstrapping; Up-and-down method