Dear all,

I would like to ask handling missing data in case control data-set (1:2) matched on age and sex factor. Let's say there are 1000 cases and 2000 controls.

1) I would like to remove the whole matched group which contained missing values in education .
For example, 100 cases had no information about education. So I want to remove all cases and as well their respective controls (200 controls). I have group variables for each case-control set.

2) As shown in below table, sex information are missing for all controls. So how can I replace sex information for each controls which will be same as respective cases?
ID case group education age Sex
1 1 1 . 25 Male
2 0 1 1 25 .
3 0 1 2 25 .
4 1 2 . 30 Female
5 0 2 2 30 .
6 0 2 1 30 .
7 1 3 . 40 Male
8 0 3 1 40 .
9 0 3 1 40 .
2998 1 1000 1 35 Male
2999 0 1000 2 35 .
3000 0 1000 1 35 .
Thanks in advance,

Kind Regards,
Moon Lu