Answer:
longitudinal
Step-by-step explanation:
Longitudinal design: The term longitudinal study is also referred to as a panel study or longitudinal survey. This is a type of research design that encompasses repeated observation of specific variables for long and short-periods, for example, people. A longitudinal study is purely qualitative.
Example: A person being examined based on certain characteristics of different age in his or her life.
Types:
1. Panel study.
2. Cohort study.