% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/cea.R
\name{mb_icer}
\alias{mb_icer}
\title{Incremental cost-effectiveness ratio with dominance handling}
\usage{
mb_icer(cost_a, effect_a, cost_b, effect_b, label_a = "A", label_b = "B")
}
\arguments{
\item{cost_a, effect_a}{Numeric scalars. Cost and effect of
option A.}

\item{cost_b, effect_b}{Numeric scalars. Cost and effect of
option B.}

\item{label_a, label_b}{Character scalars. Labels for the two
options.}
}
\value{
An \code{mb_icer} object: a list with \code{delta_cost},
\code{delta_effect}, \code{icer}, \code{dominance} (one of \code{"a_dominates"},
\code{"b_dominates"}, \code{"b_more_costly_more_effective"},
\code{"b_less_costly_less_effective"}), and labels.
}
\description{
Computes the ICER comparing option B to option A, with explicit
handling of the four dominance regions:
\itemize{
\item \strong{A dominates} B (B costs more, delivers less): no ICER.
\item \strong{B dominates} A (B costs less, delivers more): no ICER; B is
the obvious choice.
\item \strong{B more costly, more effective}: standard ICER positive.
\item \strong{B less costly, less effective}: ICER negative — B saves
money at the expense of effect.
}
}
\details{
The ICER is the cost per additional unit of outcome from
switching from A to B:
\deqn{\text{ICER} = (C_B - C_A) / (E_B - E_A)}

If \code{delta_effect} is zero, the ICER is reported as \code{Inf}
(when costs differ) or \code{NaN} (when costs are equal).
}
\examples{
mb_icer(cost_a = 1e6, effect_a = 200, cost_b = 1.5e6, effect_b = 300,
        label_a = "Status quo", label_b = "Enhanced")
}
\references{
HM Treasury (2020). The Magenta Book, Annex A on cost-effectiveness.

Drummond, M. F., Sculpher, M. J., Claxton, K., Stoddart, G. L.,
Torrance, G. W. (2015). Methods for the Economic Evaluation of
Health Care Programmes (4th ed.). Oxford University Press.
}
\seealso{
\code{\link[=mb_cea]{mb_cea()}}, \code{\link[=mb_ceac]{mb_ceac()}}, \code{\link[=mb_inb]{mb_inb()}}.

Other cost-effectiveness: 
\code{\link{mb_cea}()},
\code{\link{mb_ceac}()},
\code{\link{mb_daly}()},
\code{\link{mb_inb}()},
\code{\link{mb_qaly}()}
}
\concept{cost-effectiveness}
