Reliability and validity of Center for Epidemiological Studies Depression Scale in different rural populations

ObjectiveTo assess the reliability and validity of Center for Epidemiological Studies Depression Scale (CES-D)among the informants of suicides and controls.MethodsTotally 202 suicide informants and 271 control informants were consecutively sampled and investigated with the questionnaire.Cronbach'sα and Pearson's correlation were used to assess the internal consistency reliability.Exploratory factor analysis,criterion validity and discriminant validity were used to test the validity of the scale.Results The Cronbach'sα of CES-D were 0.917 and 0.849 in case and control group,respectively.The corrected item-total correlations in suicides and controls were 0.255-0.815 and 0.168-0.684, respectively(both P<0.01),suggesting the scale had good internal consistency reliability.Three factors were extracted by using exploratory factor analysis from 20 items(including affective and somatic symptoms,positive emotion,and interpersonal problems),which could explain 52.539% of total variance.In addition,69 samples were randomly sampled from the control informants.There were positive correlations between affective and somatic symptoms,positive emotion,CES-D and Beck Hopelessness Scale(BHS).The scale showed good criterion validity.There were 59 depressed subjects and 414 non-depressed subjects among the 473 informants.The scores of affective and somatic symptoms,positive emotion,interpersonal problems and CES-D were 17.44±5.86,9.00±4.51,0.88±1.68,and 27.32±9.05 in depression group,which were all higher than non-depression group(1.73±2.80,1.20±1.97,0.08±0.42,and 3.00±3.92),with significant differences between depression and non-depression group(all P<0.001).The scale was proved having good discriminant validity.ConclusionCES-D has high reliability and validity and is applicable to assess depression in rural residents.