Dear Stata users,

I am trying to balance the differences in duration of diabetes within each age of diagnosis group (matching set within each age of diagnosis group by duration of diabetes of 2 yrs) so as to allow for mean comparison (annual change in x variable) of these groups. I have looked at the Stata manuals; but not sure how to construct the analysis. I would really appreciate if anyone may guide/help me.

Data looks as below:
PHP Code:
 [CODE]
* Example generated by -dataex-. To install: ssc install dataex
clear
input long ID float diabetes_duration byte gender double age float(age_ds_gr change_x) byte dup
1 26 0 60.8 1 -1.6655158 0
2 14 1   55 2  .19934218 0
3  1 1 57.3 3          . 2
5  6 0 47.1 2 -.29966295 0
6  5 1 56.7 3  -5.175216 0
7 11 0   60 2   .2080694 0
8  6 0   55 2   -.058939 0
9 15 0 69.9 3 -1.2625084 0
10 22 0 70.4 2 -1.0328121 0
11 14 1 52.7 1  -.7431965 0
12 17 1 72.2 3 -2.0354166 0
13  8 0   61 3  -.3058444 0
18 28 0 59.8 1  2.2740536 0
19 17 1 64.3 2   .9247662 0
26 21 0 56.2 1 -2.9573734 0
27 25 1 74.1 2  -.9741772 0

end
[/CODE] 

Thank you very much

Oyun