Assign treatment

Source: R/group_data.R

Assign treatment

trtAssign(
  dtName,
  nTrt = 2,
  balanced = TRUE,
  strata = NULL,
  grpName = "trtGrp",
  ratio = NULL
)

Arguments

dtName

data table
nTrt

number of treatment groups
balanced

indicator for treatment assignment process
strata

vector of strings representing stratifying variables
grpName

string representing variable name for treatment or exposure group
ratio

vector of values indicating relative proportion of group assignment

Value

An integer (group) ranging from 1 to length of the probability vector

See also

trtObserve

Examples

dt <- genData(15)

dt1 <- trtAssign(dt, nTrt = 3, balanced = TRUE)
dt1[, .N, keyby = trtGrp]

#>    trtGrp N
#> 1:      1 5
#> 2:      2 5
#> 3:      3 5

dt2 <- trtAssign(dt, nTrt = 3, balanced = FALSE)
dt2[, .N, keyby = trtGrp]

#>    trtGrp N
#> 1:      1 4
#> 2:      2 3
#> 3:      3 8

def <- defData(varname = "male", formula = .4, dist = "binary")
dt <- genData(1000, def)
dt

#>         id male
#>    1:    1    0
#>    2:    2    1
#>    3:    3    1
#>    4:    4    1
#>    5:    5    0
#>   ---          
#>  996:  996    1
#>  997:  997    0
#>  998:  998    0
#>  999:  999    1
#> 1000: 1000    0

dt3 <- trtAssign(dt, nTrt = 5, strata = "male", balanced = TRUE, grpName = "Group")
dt3

#>         id male Group
#>    1:    1    0     3
#>    2:    2    1     2
#>    3:    3    1     5
#>    4:    4    1     4
#>    5:    5    0     1
#>   ---                
#>  996:  996    1     1
#>  997:  997    0     3
#>  998:  998    0     3
#>  999:  999    1     2
#> 1000: 1000    0     5
dt3[, .N, keyby = .(male, Group)]

#>     male Group   N
#>  1:    0     1 122
#>  2:    0     2 122
#>  3:    0     3 122
#>  4:    0     4 121
#>  5:    0     5 121
#>  6:    1     1  79
#>  7:    1     2  78
#>  8:    1     3  78
#>  9:    1     4  78
#> 10:    1     5  79
dt3[, .N, keyby = .(Group)]

#>    Group   N
#> 1:     1 201
#> 2:     2 200
#> 3:     3 200
#> 4:     4 199
#> 5:     5 200

dt4 <- trtAssign(dt, nTrt = 5, strata = "male", balanced = FALSE, grpName = "Group")
dt4[, .N, keyby = .(male, Group)]

#>     male Group   N
#>  1:    0     1 119
#>  2:    0     2 125
#>  3:    0     3 117
#>  4:    0     4 124
#>  5:    0     5 123
#>  6:    1     1  70
#>  7:    1     2  91
#>  8:    1     3  66
#>  9:    1     4  84
#> 10:    1     5  81
dt4[, .N, keyby = .(Group)]

#>    Group   N
#> 1:     1 189
#> 2:     2 216
#> 3:     3 183
#> 4:     4 208
#> 5:     5 204

dt5 <- trtAssign(dt, nTrt = 5, balanced = TRUE, grpName = "Group")
dt5[, .N, keyby = .(male, Group)]

#>     male Group   N
#>  1:    0     1 122
#>  2:    0     2 122
#>  3:    0     3 117
#>  4:    0     4 119
#>  5:    0     5 128
#>  6:    1     1  78
#>  7:    1     2  78
#>  8:    1     3  83
#>  9:    1     4  81
#> 10:    1     5  72
dt5[, .N, keyby = .(Group)]

#>    Group   N
#> 1:     1 200
#> 2:     2 200
#> 3:     3 200
#> 4:     4 200
#> 5:     5 200

dt6 <- trtAssign(dt, nTrt = 3, ratio = c(1, 2, 2), grpName = "Group")
dt6[, .N, keyby = .(Group)]

#>    Group   N
#> 1:     1 200
#> 2:     2 400
#> 3:     3 400