24- if you want to compare groups over time , then your design is :
A- within groups
24- a
لان
:Between Groups Designs
Compare it to another group (two groups)
:Within Group Designs
Can compare one group to itself over time
Cross-sectional method
- Same group of people are observed at one point in time
Longitudinal method
- Same group of people are observed at different points in time as they grow older
اعتقد ان الخطأ في السؤال لان ما حدد عدد groups :/