******************************************************************
*STATA syntax code for the computation of index*
*values with the Chinese value set (DCE and TTO hybrid)*
******************************************************************;

gen disut_mo = .
replace disut_mo = 0 if missing(disut_mo) & mobility == 1
replace disut_mo = 0.05 if missing(disut_mo) & mobility == 2
replace disut_mo = 0.183 if missing(disut_mo) & mobility == 3

gen disut_sc = .
replace disut_sc = 0 if missing(disut_sc) & selfcare == 1
replace disut_sc = 0.011 if missing(disut_sc) & selfcare == 2
replace disut_sc = 0.127 if missing(disut_sc) & selfcare == 3

gen disut_ua = .
replace disut_ua = 0 if missing(disut_ua) & activity == 1
replace disut_ua = 0.046 if missing(disut_ua) & activity == 2
replace disut_ua = 0.17 if missing(disut_ua) & activity == 3

gen disut_pd = .
replace disut_pd = 0 if missing(disut_pd) & pain == 1
replace disut_pd = 0.078 if missing(disut_pd) & pain == 2
replace disut_pd = 0.267 if missing(disut_pd) & pain == 3

gen disut_ad = .
replace disut_ad = 0 if missing(disut_ad) & anxiety == 1
replace disut_ad = 0.061 if missing(disut_ad) & anxiety == 2
replace disut_ad = 0.172 if missing(disut_ad) & anxiety == 3

gen disut_a3 = 0
replace disut_a3 = 0.158 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_a3

gen EQ_index = . 
replace EQ_index = 1 - 0.012 - disut_total
replace EQ_index = 1 if mobility == 1 & selfcare == 1 & activity == 1 & pain == 1 & anxiety == 1 
replace EQ_index = round(EQ_index, .001)