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

gen L2 = 0.176
gen P = 0.423

gen disut_mo = .
replace disut_mo = 0 if missing(disut_mo) & mobility == 1
replace disut_mo = 0.424*L2 if missing(disut_mo) & mobility == 2
replace disut_mo = 0.424 if missing(disut_mo) & mobility == 3

gen disut_sc = .
replace disut_sc = 0 if missing(disut_sc) & selfcare == 1
replace disut_sc = 0.105*L2 if missing(disut_sc) & selfcare == 2
replace disut_sc = 0.105 if missing(disut_sc) & selfcare == 3

gen disut_ua = .
replace disut_ua = 0 if missing(disut_ua) & activity == 1
replace disut_ua = 0.103*L2 if missing(disut_ua) & activity == 2
replace disut_ua = 0.103 if missing(disut_ua) & activity == 3

gen disut_pd = .
replace disut_pd = 0 if missing(disut_pd) & pain == 1
replace disut_pd = 0.180*L2 if missing(disut_pd) & pain == 2
replace disut_pd = 0.180 if missing(disut_pd) & pain == 3

gen disut_ad = .
replace disut_ad = 0 if missing(disut_ad) & anxiety == 1
replace disut_ad = 0.137*L2 if missing(disut_ad) & anxiety == 2
replace disut_ad = 0.137 if missing(disut_ad) & anxiety == 3

gen EQ_index = . 
replace EQ_index = 1-(disut_mo + disut_sc + disut_ua + disut_pd + disut_ad)^P
replace EQ_index = 1 if mobility == 1 & selfcare == 1 & activity == 1 & pain == 1 & anxiety == 1 
replace EQ_index = round(EQ_index, .001)