
Integration Point: Response - Continuous Outcome
Gabriel Potvin
October 16, 2025
IntegrationPointResponseContinuous.Rmd
Go back to the Integration Point: Response page
Input Variables
When creating a custom R script, you can optionally use specific
variables provided by East Horizon’s engine itself. These variables are
automatically available and do not need to be set by the user, except
for the UserParam
variable. Refer to the table below for
the variables that are available for this integration point and
outcome.
Variable | Type | Description |
---|---|---|
NumSub | Integer | Number of subjects in the trial. |
TreatmentID | Vector of Integer | Vector of length NumSub , indicating the allocation of
subjects to arms. Index 0 represents placebo/control. For
example, [0, 0, 1] indicates three subjects: two in the
control group and one experimental. |
NumArms | Integer | Number of arms in the trials (includes the control arm). Only
applicable when
Study Objective = Multiple Arm Confirmatory . |
Mean | Vector of Numeric | Vector of length equal to the number of arms, indicating the mean of the treatments. |
StdDev | Vector of Numeric | Vector of length equal to the number of arms, indicating the standard deviation of the treatments. |
UserParam | List | Contains all user-defined parameters specified in the East Horizon
interface (refer to the Instructions
section). To access these parameters in your R code, use the syntax:
UserParam$NameOfTheVariable , replacing
NameOfTheVariable with the appropriate parameter name. |
Expected Output Variable
East Horizon expects an output of a specific type. Refer to the table below for the expected output for this integration point:
Type | Description |
---|---|
List | A named list containing Response and
ErrorCode . |
Expected Members of the Output List
Members | Type | Description |
---|---|---|
Response | Vector of Double | Vector of length NumSub , containing the generated
responses for all subjects. |
ErrorCode | Integer | Optional. Can be used to handle errors in your script: – 0 : No error.– Positive Integer : Nonfatal
error, the current simulation will be aborted, but the next simulation
will proceed.– Negative Integer : Fatal error, no
further simulations will be attempted. |
Note: Additional custom variables can be included as members of the
output list. All outputs will automatically be available as input
variables for analysis or treatment selection endpoints in the
SimData
variable as described here: Variables of SimData.
Minimal Template
Your R script could contain a function such as this one, with a name
of your choice. All applicable input variables must be declared, even if
they are not used in the script. Input variables that are not applicable
(depending on the study objective) must not be declared. We recommend
always declaring UserParam
as a default NULL
value in the function arguments, as this will ensure that the same
function will work regardless of whether the user has specified any
custom parameters in East Horizon.
Detailed templates with step-by-step explanations are available here: SimulatePatientOutcome.Continuous.R for 2-Arm and SimulatePatientOutcome.Continuous.MAMS.R for Multiple Arm.
For Study Objective = Two Arm Confirmatory
GenerateResponse <- function( NumSub, TreatmentID, Mean, StdDev, UserParam = NULL )
{
nError <- 0 # Error handling (no error)
vPatientOutcome <- rep( 0, NumSub ) # Initializing response array to 0
# Write the actual code here.
# Store the generated continuous response values in a vector called vPatientOutcome.
return( list( Response = as.double( vPatientOutcome ), ErrorCode = as.integer( nError ) ) )
}
For Study Objective = Multiple Arm Confirmatory
GenerateResponse <- function( NumSub, NumArms, TreatmentID, Mean, StdDev, UserParam = NULL )
{
nError <- 0 # Error handling (no error)
vPatientOutcome <- rep( 0, NumSub ) # Initializing response array to 0
# Write the actual code here.
# Store the generated continuous response values in a vector called vPatientOutcome.
return( list( Response = as.double( vPatientOutcome ), ErrorCode = as.integer( nError ) ) )
}
Examples
Explore the following examples for more context:
- 2-Arm, Continuous Outcome - Patient Simulation
- Childhood Anxiety Trial
- Multiple Arm, Continuous Outcome - Patient Simulation