Observed exposure or treatment

trtObserve(dt, formulas, logit.link = FALSE, grpName = "trtGrp")

Arguments

dt

data table

formulas

collection of formulas that determine probabilities

logit.link

indicator that specifies link. If TRUE, then logit link is used. If FALSE, the identity link is used.

grpName

character string representing name of treatment/exposure group variable

Value

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

See also

Examples

def <- defData(varname = "male", dist = "binary", formula = .5, id = "cid") def <- defData(def, varname = "over65", dist = "binary", formula = "-1.7 + .8*male", link = "logit") def <- defData(def, varname = "baseDBP", dist = "normal", formula = 70, variance = 40) dtstudy <- genData(1000, def) dtstudy
#> cid male over65 baseDBP #> 1: 1 0 0 75.16916 #> 2: 2 0 0 76.26197 #> 3: 3 1 1 66.78133 #> 4: 4 0 0 71.67887 #> 5: 5 1 0 64.18112 #> --- #> 996: 996 0 1 69.86304 #> 997: 997 1 0 63.88180 #> 998: 998 0 0 72.93428 #> 999: 999 0 0 79.72073 #> 1000: 1000 1 0 81.65354
formula1 <- c("-2 + 2*male - .5*over65", "-1 + 2*male + .5*over65") dtObs <- trtObserve(dtstudy, formulas = formula1, logit.link = TRUE, grpName = "exposure") dtObs
#> cid exposure male over65 baseDBP #> 1: 1 1 0 0 75.16916 #> 2: 2 3 0 0 76.26197 #> 3: 3 2 1 1 66.78133 #> 4: 4 2 0 0 71.67887 #> 5: 5 3 1 0 64.18112 #> --- #> 996: 996 3 0 1 69.86304 #> 997: 997 2 1 0 63.88180 #> 998: 998 1 0 0 72.93428 #> 999: 999 3 0 0 79.72073 #> 1000: 1000 2 1 0 81.65354
# Check actual distributions dtObs[, .(pctMale = round(mean(male), 2)), keyby = exposure]
#> exposure pctMale #> 1: 1 0.61 #> 2: 2 0.71 #> 3: 3 0.24
dtObs[, .(pctMale = round(mean(over65), 2)), keyby = exposure]
#> exposure pctMale #> 1: 1 0.15 #> 2: 2 0.27 #> 3: 3 0.15
dtSum <- dtObs[, .N, keyby = .(male, over65, exposure)] dtSum[, grpPct := round(N / sum(N), 2), keyby = .(male, over65)]
#> male over65 exposure N grpPct #> 1: 0 0 1 52 0.12 #> 2: 0 0 2 110 0.25 #> 3: 0 0 3 280 0.63 #> 4: 0 1 1 3 0.05 #> 5: 0 1 2 18 0.29 #> 6: 0 1 3 41 0.66 #> 7: 1 0 1 69 0.20 #> 8: 1 0 2 207 0.59 #> 9: 1 0 3 77 0.22 #> 10: 1 1 1 18 0.13 #> 11: 1 1 2 101 0.71 #> 12: 1 1 3 24 0.17
dtSum
#> male over65 exposure N grpPct #> 1: 0 0 1 52 0.12 #> 2: 0 0 2 110 0.25 #> 3: 0 0 3 280 0.63 #> 4: 0 1 1 3 0.05 #> 5: 0 1 2 18 0.29 #> 6: 0 1 3 41 0.66 #> 7: 1 0 1 69 0.20 #> 8: 1 0 2 207 0.59 #> 9: 1 0 3 77 0.22 #> 10: 1 1 1 18 0.13 #> 11: 1 1 2 101 0.71 #> 12: 1 1 3 24 0.17