sample_size: Function to calculate the estimated sample size based on the...

In EBASS: Expected Value of Information Based Sample Size Calculation

Function to calculate the estimated sample size based on the Expected Value of Perfect Information (EVPI)

Description

This function calculates the optimal total sample size for a planned cost-effectiveness study. The optimal sample size is reached when the marginal EVPI gain is less than or equal to the marginal cost of inclusion: (step_ref + step_exp) * cost_indiv.

Usage

sample_size(object_evpi_decrease, cost_indiv)

Arguments

object_evpi_decrease	An evpi_decrease object. See create_object_evpi_decrease
cost_indiv	cost of an additional inclusion in your planned cost-effectiveness study.

Value

A dataframe containing three columns :

N	Total sample size of the planned cost-effectiveness study
N_exp	Sample size in the experimental group
N_ref	Sample size in the reference group

EBASS documentation built on Sept. 4, 2026, 5:07 p.m.