******************************************************************
*STATA syntax code for the computation of index*
*values with the Singaporean value set (TTO)*
******************************************************************;

gen disut_mo = .
replace disut_mo = 0 if missing(disut_mo) & mobility == 1
replace disut_mo = 0.1678 if missing(disut_mo) & mobility == 2
replace disut_mo = 0.304 if missing(disut_mo) & mobility == 3

gen disut_sc = .
replace disut_sc = 0 if missing(disut_sc) & selfcare == 1
replace disut_sc = 0.1615 if missing(disut_sc) & selfcare == 2
replace disut_sc = 0.3465 if missing(disut_sc) & selfcare == 3

gen disut_ua = .
replace disut_ua = 0 if missing(disut_ua) & activity == 1
replace disut_ua = 0.2555 if missing(disut_ua) & activity == 2
replace disut_ua = 0.3209 if missing(disut_ua) & activity == 3

gen disut_pd = .
replace disut_pd = 0 if missing(disut_pd) & pain == 1
replace disut_pd = 0.1462 if missing(disut_pd) & pain == 2
replace disut_pd = 0.2291 if missing(disut_pd) & pain == 3

gen disut_ad = .
replace disut_ad = 0 if missing(disut_ad) & anxiety == 1
replace disut_ad = 0.1501 if missing(disut_ad) & anxiety == 2
replace disut_ad = 0.2784 if missing(disut_ad) & anxiety == 3

gen disut_n3 = 0
replace disut_n3 = 0.2905  if mobility == 3 | selfcare == 3 | activity == 3 | pain == 3 | anxiety == 3

gen disut_total = disut_mo + disut_sc + disut_ua + disut_pd + disut_ad + disut_n3

gen EQ_index = . 
replace EQ_index = 1- disut_total
replace EQ_index = 1 if mobility == 1 & selfcare == 1 & activity == 1 & pain == 1 & anxiety == 1 
replace EQ_index = round(EQ_index, .001)