Derivation
variable: intdate [interview date] (table[s]: tb_tbx, tb_tbxto2007, tbold_tbpart1/2, tb_tbo, tb_tboto2007, tbold_control)
variable: firsthivposdate [first HIV positive test date] (table[s]: hivart_kps_known_all)
variable: neg_date* [HIV negative date(s)] (table[s]: hivart_kps_known_all)
<Create using HIV test dates: assign someone as negative if any neg report was up to 3 years before and 1 month after interview date and as positive if first pos report was any time before and up to a year after interview>
gen datehiv=intdate
replace datehiv=starteps if starteps~=.
merge m:1 ident using ${hivdata}\hivart_kps_known_all, keep(master match) keepusing(firsthivposdate lastneverart_date firstart_date lastonart_date lastartstop_date neg_date*) nogen
gen hivstatus=.
gen nearesthivnegdate=.
lookfor neg_date
foreach neg_date in `r(varlist)' {
replace nearesthivnegdate=`neg_date' if datehiv-`neg_date'<=(365.25*3) & datehiv-`neg_date'>=-31 & `neg_date'~=.
replace hivstatus=0 if datehiv-`neg_date'<=(365.25*3) & datehiv-`neg_date'>=-31 & `neg_date'~=.
}
replace hivstatus=1 if datehiv>=firsthivposdate-365.25
la val hivstatus np
