no smd (standardized mean differences) shown by tableone::CreateTableOne

Question

In R, I am trying to use tableone::CreateTableOne in order to calculate smd (standardized mean differences) on a dataframe. I used this tutorial (https://cran.r-project.org/web/packages/tableone/vignettes/smd.html) - the code runs and nicely produces the desired output table, including the smd.

However, if I use my own data, e.g. the test data below, I get the table but without smd. Probably I did some stupid mistake, but after trying a lot of things (only numeric, smaller or larger dataset, categorial variables as factor (as in r help) or character (as in tutorial)...) I cannot figure out why I do not get smd.

# package tableone for CreateTableOne
if (!require("tableone"))  install.packages("tableone");  library("tableone") 
# producible test data
set.seed(1234)
d <- data.frame(age = rnorm(n = 200, mean = 50, 9),
                hair = as.factor(sample(x = c("brown", "black", "blond"), 200, replace = T)),
                group = sample(x = c("sick", "healthy"), 200, replace = T))
str(d)
# calculate and print the table
tabUnmatched <- tableone::CreateTableOne(vars = c("age", "hair"), strata = "group", data = d, test = FALSE, smd = TRUE)
print(tabUnmatched)

results in the following table, WITHOUT smd (and no error message):

                 Stratified by group
                  healthy       sick         
  n                  90           110        
  age (mean (SD)) 49.18 (7.97)  49.72 (10.10)
  hair (%)                                   
     black           30 (33.3)     35 (31.8) 
     blond           33 (36.7)     43 (39.1) 
     brown           27 (30.0)     32 (29.1) 

What am I doing wrong, what do I need to do to get smd output?

Answer 1

errr...this?

print(tabUnmatched, smd = TRUE)

                Stratified by group
                  healthy       sick          SMD   
  n                  90           110               
  age (mean (SD)) 49.18 (7.97)  49.72 (10.10)  0.059
  hair (%)                                     0.050
     black           30 (33.3)     35 (31.8)        
     blond           33 (36.7)     43 (39.1)        
     brown           27 (30.0)     32 (29.1)