BCEA (version 1.0)

contour2: Specialised contour plot for objects in the class "bcea"

Description

Produces a scatterplot of the cost-effectiveness plane, with a contour-plot of the bivariate density of the differentials of cost (y-axis) and effectiveness (x-axis). Also adds the sustainability area (ie below the selected value of the willingness-to-pay threshold).

Usage

contour2(he, wtp=25000, xl=NULL, yl=NULL)

Arguments

he

A "bcea" object containing the results of the Bayesian modelling and the economic evaluation

wtp

The selected value of the willingness-to-pay. Default is 25000

xl

Limits on the x-axis (default=NULL, so that R will select appropriate limits)

yl

Limits on the y-axis (default=NULL, so that R will select appropriate limits)

Value

• Plots the cost-effectiveness plane with a scatterplot of all the simulated values from the (posterior) bivariate distribution of (Delta_e,Delta_c), the differentials of effectiveness and costs; superimposes a contour of the distribution and prints the value of the ICER, together with the sustainability area

References

Baio, G., Dawid, A. P. (2011). Probabilistic Sensitivity Analysis in Health Economics. Statistical Methods in Medical Research doi:10.1177/0962280211419832.

Baio G. (2012). Bayesian Methods in Health Economics. CRC/Chapman Hall, London

See Also

bcea ceplane.plot

Examples

# See Baio G., Dawid A.P. (2011) for a detailed description of the 
# Bayesian model and economic problem
#
# Load the processed results of the MCMC simulation model
data(Vaccine)
# 
# Runs the health economic evaluation using BCEA
m <- bcea(e=e,c=c,          # defines the variables of 
                            #  effectiveness and cost
      ref=2,                # selects the 2nd row of (e,c) 
                            #  as containing the reference intervention
      interventions=treats, # defines the labels to be associated 
                            #  with each intervention
      Kmax=50000            # maximum value possible for the willingness 
                            #  to pay threshold; implies that k is chosen 
                            #  in a grid from the interval (0,Kmax)
)
#
# Plots the contour and scatterplot of the bivariate 
#   distribution of (Delta_e,Delta_c)
contour2(m,       # uses the results of the economic evalaution 
                  #  (a "bcea" object)
      wtp=25000,  # selects the willingness-to-pay threshold
      xl=NULL,    # assumes default values
      yl=NULL     # assumes default values
)