Abstract
Studying age-related change in psychosocial behavior is difficult because manifestation differs with development. While the use of age-appropriate measurement instruments addresses developmental differences, changes in measurement also challenge researchers' ability to study developmental trajectories. Leveraging 8-occasion data from 262 girls (baseline ages 11 and 17 years) participating in a cross-sequential study spanning childhood to adulthood, this paper (1) highlights the needs of developmental researchers seeking to measure change across large swaths of development, (2) forwards an initial formula to convert Beck Depression Inventory-II scores into Children's Depression Inventory scores and facilitate longitudinal analysis and understanding of how depression develops across adolescence, and (3) suggests collection and analysis of new data that would better facilitate researcher's linking of child-, adolescent-, and adult-oriented measurement instruments.