Hello,
I’d like to create a new binary variable that is derived from a continuous one, conditional on a third (also continuous) variable. Specifically, I’d like to create a variable sga
that is derived from birth_weight
: sga
is small for gestational age, so the conditional variable is ga
(gestational age of the subject).
I was initially trying with the “standard” datashield but then realised it was possible to install dsBetaTest
on the node so was able to look at using some of the new fuctions  specifically, I tried using ds.make.o()
. However, I still cannot figure it out.
The logic I am trying to implement is as follows:

generated expected (
bw50c
) birth weight for the subject (ofga = X
whereX
is a continuous variable from 22 to 40) using a formula based on the known median birth weight at 40 weeks gestation 
generate
sga
indicator variable as follows:sga == 1 if birth_weight < (bw50c  3*sd)
sga == 0 if birth_weight >= (bw50c  3*sd)
nb:
sd
is a known standard deviation.
Is anyone able to advise if this is possible using available (including beta) datashield functions and, if so, how I might solve this? I am sure I am probably just being a bit dumb and overlooking something…
Thanks in advance!
Andrei