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Dear LimeSurvey friends, 

I would really appreciate if you could help me doing a randomization by gender. 
It is important for my experiment to have more or less the same amount of men and women on the control and intervention groups. I have thought that the best way might be to have four clusters... Cluster 1: woman control group. Cluster 2: men control group. Cluster 3: women intervention group. Cluster 4: men intervention group. 

How could I do this with LimeSurvey?

Thank you very much. 

Ignacio

Hi, Ignacio,
the only difference to the simple randomization by a random number is the second condition (gender)
So, create a random number ("randnum") (1-2) the usual way
{if(is_empty(randnum),rand(1,2),randnum)}
and you have the "relevance equation" or "condition" (because you didn't answer the initial questions I do not know how it is called in your version)
1. men control: randnum==1 AND QSex==1
2. men intervention: randnum==2 AND QSex==1
3. women control: randnum==1 AND QSex==2
4. women intervention: randnum==2 AND QSex==2
with question QSex coded "1=men, 2=women"

Joffm