Measurement equivalence of the CES-D 8 depression-scale among the ageing population in eleven European countries.

Depression is one of the most prevalent mental disorders in later life. However, despite considerable research attention, great confusion remains regarding the association between ageing and depression. There is doubt as to whether a depression scale performs identically for different age groups and countries. Although measurement equivalence is a crucial prerequisite for valid comparisons across age groups and countries, it has not been established for the eight-item version of the Centre for Epidemiological Studies Depression Scale (CES-D8). Using multi-group confirmatory factor analysis, we assess configural, metric, and scalar measurement equivalence across two age groups (50-64 years of age and 65 or older) in eleven European countries, employing data from the Survey of Health, Ageing, and Retirement (SHARE). Results indicate that the construct of depression is comparable across age and country groups, allowing the substantive interpretation of correlates and mean levels of depressive symptoms.