********************************************************************
* File			    HALCyon wellbeing syntax_NSHD.do
* BY				Rachel Cooper, MRC Unit for Lifelong Health and Ageing at UCL
* FOR				HALCyon cross-cohort collaboration (funded by the New Dynamics of Ageing (RES-353-25-0001))
* DATASET			MRC National Survey of Health and Development
* Date Created 		25/07/2011
* last modified	    26/02/2013

* PURPOSE			Derives Warwick Edinburgh Mental Wellbeing Score (WEMWBS) for use in cross-cohort analyses
*************************************************************************************

#delimit ;
set more off ;

tab1 wemwba09-wemwbn09 ;

/*Individual coding changes required to variables where people gave 2 response items*/
replace wemwbk09=3.5 if serno==10125 ;
replace wemwbd09=3 if serno==11024 ;
replace wemwbl09=4.5 if serno==22178 ;
replace wemwbj09=3.5 if serno==24073 ;
replace wemwbc09=3.5 if serno==51021 ;
replace wemwbl09=4 if serno==73057 ;
replace wemwbm09=3.5 if serno==78023 ;
replace wemwbl09=4 if serno==103031 ;
replace wemwbe09=3.5 if serno==104006 ;
replace wemwbk09=4.5 if serno==125294 ;
replace wemwbf09=2.5 if serno==127010 ;
replace wemwba09=3.5 if serno==139071 ;
replace wemwbd09=1.5 if serno==148053 ;
replace wemwbg09=4.5 if serno==185035 ;
replace wemwbb09=3.5 if serno==208007 ;
replace wemwbb09=4 if serno==456002 ;

tab1 wemwba09-wemwbn09 ;

/*Code out people with missing values */
replace wemwba09=. if wemwba09>5 ;
replace wemwbb09=. if wemwbb09>5 ;
replace wemwbc09=. if wemwbc09>5 ;
replace wemwbd09=. if wemwbd09>5 ;
replace wemwbe09=. if wemwbe09>5 ;
replace wemwbf09=. if wemwbf09>5 ;
replace wemwbg09=. if wemwbg09>5 ;
replace wemwbh09=. if wemwbh09>5 ;
replace wemwbi09=. if wemwbi09>5 ;
replace wemwbj09=. if wemwbj09>5 ;
replace wemwbk09=. if wemwbk09>5 ;
replace wemwbl09=. if wemwbl09>5 ;
replace wemwbm09=. if wemwbm09>5 ;
replace wemwbn09=. if wemwbn09>5 ;



/*Generating variable to indicate number of items missing */
egen wemwbs09m=rmiss(wemwba09-wemwbn09) ;
egen scorepreimp=rsum( wemwba09- wemwbn09) if  wemwbs09m>=0 &  wemwbs09m<=3 ;
gen  wemwbstot= scorepreimp ;
replace wemwbstot=(scorepreimp+(scorepreimp/13)) if  wemwbs09m==1 ;
replace wemwbstot=(scorepreimp+((scorepreimp/12)*2)) if  wemwbs09m==2 ;
replace wemwbstot=(scorepreimp+((scorepreimp/11)*3)) if  wemwbs09m==3 ;

label variable wemwbs09m "No. of items missing - WEMWBS" ;
label variable wemwbstot "Total WEMWBS score" ;

drop scorepreimp ;