Notes
Variable créée à partir des variables a7m, a7a, a7nm et a7na
Programme Stata :
gen date1= mdy(a7m,1,a7a)
replace date1= mdy(7,1,a7a) if a7m==.
gen s1 = dateinter - date1
gen s2 = a7nm*30.4
gen s3 = a7na*365.25
capture drop a7_r
egen a7_r= rowtotal(s1 s2 s3)
replace a7_r = 15 if a7_r<0 // deux cas
replace a7_r=15 if a7==6
replace a7_r=. if inlist(a7,7,8)
replace a7_r=. if samplea5==0
replace a7_r= a7_r/365.25