Are there differences in depression across biological sex and developmental phases? Examining the structure and measurement invariance of depressive symptoms in males and females from childhood through adolescence.

Depressive symptoms increase markedly in adolescence, especially among females. It remains unclear whether this reflects age- and sex-related changes in levels of the same construct or differences in the nature or expression of depression. We examined whether depression is structurally equivalent across age and sex. A community sample of 481 youth was assessed from age 9 to 18 at 3-year intervals. At each wave, participants completed the Children's Depression Inventory. We evaluated the Children's Depression Inventory factor structure and tested measurement invariance (MI) across development and sex. A unidimensional structure was supported at all waves. Developmental MI analyses indicated configural, metric, and partial scalar invariance. Sex-based MI analyses within the longitudinal framework showed similar results. Depression appears largely structurally consistent across development and sex, although its expression may vary slightly as a function of changing contexts and socioemotional development. (PsycInfo Database Record (c) 2026 APA, all rights reserved).