This function displays a two-way sensitivity analysis (TWSA) graph by estimating a linear regression metamodel of a PSA for a given decision-analytic model
twsa(
sa_obj,
param1 = NULL,
param2 = NULL,
ranges = NULL,
nsamp = 100,
outcome = c("eff", "cost", "nhb", "nmb", "nhb_loss", "nmb_loss"),
wtp = NULL,
strategies = NULL,
poly.order = 2
)sensitivity analysis object;
either a probabilistic sensitivity analysis (make_psa_obj) or
a deterministic sensitivity analysis object (run_owsa_det)
String with the name of the first parameter of interest
String with the name of the second parameter of interest
a named list of the form c("param" = c(0, 1), ...)
that gives the ranges for the parameter of interest. If NULL,
parameter values from the middle 95
from this range is determined by nsamp.
number of samples from ranges
either effectiveness ("eff"), cost ("cost"), net health benefit ("nhb"), net monetary benefit ("nmb"), or the opportunity loss in terms of NHB or NMB ("nhb_loss" and "nmb_loss", respectively). "nmb_loss_voi" and "nhb_loss_voi" are only used in internal function calls of metamodel within other VOI functions.
if outcome is NHB or NMB (or the associated loss), must provide the willingness-to-pay threshold
vector of strategies to consider. The default (NULL) is that all strategies are considered.
order of polynomial for the linear regression metamodel. Default: 2
twsa A ggplot2 object with the TWSA graph of param1 and
param2 on the outcome of interest.