Psychometric properties of the EURO-D scale of depressive symptomatology: Evidence from SHARE wave 8

Background The EURO-D is a short scale to measure symptoms of depression, very used in large population surveys. Although there are numerous validation studies, its psychometric properties remain unclear. The two-factor structure (Affective Suffering and Lack of Motivation) is replicated in several studies but with different item compositions, and none reported reliability indices for both factors. For that reason, the aim of this study is to examine the factorial validity of the scale, the reliability of the dimensions, the gender differential item functioning (DIF), and the nomological validity. Methods 46,317 participants aged 50 and over (M = 71.33), from which 57.4 % were females, in Wave 8 of the Survey of Health, Aging and Retirement in Europe (SHARE) were included. Instruments: EURO-D, R-UCLA, Self-perceived health index, and indicator of taking drugs for anxiety or depression. Factor Analyses, DIF, Reliability Index and Spearman correlations were estimated. Results Factor analysis identified a bifactor structure: a general factor of Depression and two specific factors of Affective Suffering and Lack of Motivation, which reliabilities were 0.83, 0.83 and 0.79 respectively. No relevant DIF item by gender was found, but higher scores were found in women in all factors. Both factors had positive relations with loneliness, taking drugs and self-perceived health. Limitations this study has a cross-sectional design; future research may consider the longitudinal stability of the scale. Conclusions EURO-D shows adequate psychometric properties when a general factor of depression and two specific factors are considered. Women have higher scores on all dimensions.