fct_infreq does not work when strata are present

[alexflaris]

Hello,

I am trying to use fct_infreq with strata for tableby and the output is not correct.

Example with mtcars:

library(arsenal)

Table <- tableby( ~ fct_infreq(as.factor(gear)), strata = as.factor(cyl), data = mtcars)

summary(Table)

And the output is:

|as.factor(cyl) |                                | Overall (N=32) |
|:--------------|:-------------------------------|:--------------:|
|4              |**fct_infreq(as.factor(gear))** |                |
|               |   3             |    1 (9.1%)    |
|               |   4             |   8 (72.7%)    |
|               |   5             |   2 (18.2%)    |
|6              |**fct_infreq(as.factor(gear))** |                |
|               |   3             |   2 (28.6%)    |
|               |   4             |   4 (57.1%)    |
|               |   5             |   1 (14.3%)    |
|8              |**fct_infreq(as.factor(gear))** |                |
|               |   3             |   12 (85.7%)   |
|               |   4             |    0 (0.0%)    |
|               |   5             |   2 (14.3%)    |

I would have guessed that the factors would be sorted by frequency within each stratum, so that the final output would have been something like:

stratum 4: 4, 5, 3
stratum 6: 4, 3, 5
stratum 8: 3, 5, 4

Is there something different that needs to be done so that factor levels are sorted within each stratum?

Thank you,
Alex