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giabaio / BCEA

Bayesian Cost Effectiveness Analysis. Given the results of a Bayesian model (possibly based on MCMC) in the form of simulations from the posterior distributions of suitable variables of costs and clinical benefits for two or more interventions, produces a health economic evaluation. Compares one of the interventions (the "reference") to the others ("comparators"). Produces many summary and plots to analyse the results
https://gianluca.statistica.it/software/bcea/
GNU General Public License v3.0
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Changing the reference in multiple comparisons #4

Closed joliveiracosta closed 5 years ago

joliveiracosta commented 6 years ago

Hi, I would like to plot a comparison of A, B, C, with A as the reference. Using the standard ceplane.plot, it plots A-B, and A-C. However, I wanted to show B-A and C-A. Is it possible to change it?

giabaio commented 6 years ago

Hi Juliana, In BCEA terminology, the "reference" intervention is the one you're assessing to see if it's more cost-effective than the comparator(s). That's why it produces the plots in terms of A vs B and A vs C, because the analysis is all about A vs the others (assuming A is your "reference" intervention). Why exactly do you want B vs A and C vs A?

In any case, the simplest solution is to use the output to the call to bcea and slightly modify it to get ceplane.plot to do what you want, for example

library(BCEA)
data(Smoking)
m=bcea(e,c,ref=4)
m2=m
m2$delta.e=-m2$delta.e
m2$deltac=-m2$delta.c
m2$ref=m$comp
m2$comp=m$ref
ceplane.plot(m2)

This way, you obtain the plots in the format you want --- the price to pay (eg duplicate the bcea object and then modify some of its elements) seems minimal... I am happy to think about modifying the actual function if you have a strong rationale for wanting the plot the way you mention, though!

HTH Gianluca

joliveiracosta commented 6 years ago

Hi Gianluca, In the perspective I am conducting the CEA, the reference is the standard treatment (sometimes known as the available treatment already offered in the Health Care System), and the other alternatives should be compared against it, as they are newly launched technologies. That is why I wanted to know if the new ones are cost-effective compared to the "reference". I have run the code you provided and it worked perfectly. I just corrected the 6th line, where m2$delta.c was missing the ".". Thank you for your support!
Cheers,