Define a dynamic intervention rule — dyn

Captures an R expression for a dynamic (rule-based) exposure intervention. The expression is evaluated at each time step inside the simulated data.table, so any column in the current Monte Carlo dataset can be referenced by name (including the exposure itself, which holds its natural-course draw at the time of evaluation).

Usage

dyn_int(expr)

Arguments

expr: An R expression that returns a numeric (or logical coerced to numeric) vector with one value per row. Column names from the current simulated dataset are in scope (e.g. L1, A).

Value

An object of class "causalMed_dynint".

Examples

# Treat only if the natural-course value of A exceeds 0:
dyn_int(as.numeric(A > 0))
#> [[1]]
#> as.numeric(A > 0)
#> 
#> attr(,"class")
#> [1] "causalMed_dynint"

# Treat if L1 > 0 or L2 equals 1:
dyn_int(as.numeric(L1 > 0 | L2 == 1))
#> [[1]]
#> as.numeric(L1 > 0 | L2 == 1)
#> 
#> attr(,"class")
#> [1] "causalMed_dynint"