Fei Gao|Nan Luo|Julian Thumboo|Calvin Fones|Shu?Chuen Li|Yin?Bun Cheung
Does the 12-item General Health Questionnaire contain multiple factors and do we need them?
National Cancer Centre Singapore|Institute of Health Economics|Singapore General Hospital|National University of Singapore|National University of Singapore|London School of Hygiene & Tropical Medicine
12item general health questionnaire ghq12 widely used unidimensional instrument factor analyses tended suggest contains two three factors much known usefulness ghq12 factors exist revealing betweenpatient differences clinical states healthrelated quality lifewe addressed issue crosssectional survey outpatients psychological disorders singapore participants n 120 completed ghq12 beck anxiety inventory shortform 36 health survey confirmatory factor analysis used compare six previously proposed factor structures ghq12 factor scores bestfitting model well overall ghq12 score assessed relation clinical healthrelated quality life variablesthe 3factor model proposed graetz fitted data better unidimensional model two 2factor models two 3factor models however three factors strongly correlated values varied similar fashion relation clinical healthrelated quality life variablesthe 12item general health questionnaire contains three factors namely anxiety depression social dysfunction loss confidence nevertheless using separately offer many practical advantages differentiating clinical groups identifying association clinical healthrelated quality life variables