create_object_inmb: Create an object INMB

In EBASS: Sample Size Calculation Method for Cost-Effectiveness Studies Based on Expected Value of Perfect Information

Description

The net monetary benefit (NMB) of an intervention is given by E x Lambda - C, where E and C are the effectiveness and cost of this intervention, and Lambda is the threshold value for a unit of effectiveness, the ceiling incremental cost-effectiveness ratio. When the NMB is positive, the value of the intervention's effectiveness overpasses its cost. When evaluating the cost-effectiveness of a new intervention in comparison with the reference, one can estimate the difference between the net monetary benefit of the new or experimental intervention (NMBn) and the net monetary benefit of the reference (NMBr). This difference is known as the incremental net monetary benefit (INMB), which is given by: INMB = NMBn - NMBr = de x lambda - dc. The new intervention is cost-effective if INMB is positive.

Usage

create_object_inmb(de, dc, object_lambda)

Arguments

de	: Expected point estimate of the difference in mean effectiveness (effectiveness in the experimental group minus effectiveness in the reference group)
dc	: Expected point estimate of the difference in mean cost (cost in the experimental group minus cost in the reference group)
object_lambda	: object containing the ceiling cost-effectiveness ratio or maximum acceptable cost of a unit of effectiveness. See create_object_lambda

Value

create_object_inmb returns an object of class INMB which inherits from the class INMB_DIRECT

See Also

create_object_inmb_direct for INMB directly defined

Examples

## First, create a lambda object
object_lambda <- create_object_lambda (20000)
## Then, create an inmb object
object_inmb <- create_object_inmb(de = 0.04, dc=-168, object_lambda = object_lambda)
## inmb is calculated by methods inside the object. Retrieve the inmb :
object_inmb$get_inmb()

Example output

[1] 968

EBASS documentation built on May 1, 2019, 6:54 p.m.