The same cohort of learners is studied in Grades 6, 7 and 8 to examine change in academic self-concept. This is a:

Correct answer: longitudinal study Studying the same cohort repeatedly over Grades 6, 7 and 8 is a longitudinal study.

• cross-sectional study A cross-sectional study collects data at one time, often from different groups.
• case-control study A case-control study compares people with and without an outcome.
• post-test-only study A post-test-only study measures once after treatment.