Unit 4: Kinds of study time points

• - 2 or more time points
• - can establish time sequences
• - can establish causality (if design is experimental)
• - can describe change
• - can describe current conditions

-It examines age changes in one group of subjects at more than one point in time.

Adv: Allows study of development over extended period of time, same people studied so they act as own control (has own background, genetic, ethnic)

Disadv: Very expensive, staff costs increase from yr to yr., and people dropout

• - 1 measurement time point, sequential age groups (mulitple group)
• - cannot establish time sequences & causality
• - can weakly describe change

• - 1 measurement time point, one age group (snap shot)
• - cannot establish time sequences, causality, or describe change
• - can describe current conditions

-Examines several groups and their age differences not changes

Adv: less expensive and dropouts minimized because of short time period

Disadv: lack of comparability, gives no idea of direction of change group may take, and reveals nothing about continuity of development

Can help answer developmental questions with less time and expense than a traditional study.

- Has descriptive value but not explanatory value

- Can tell us what is happening but not why

6: Evaluation    2+

5: Intervention  2+

4: Prediction     2+

3: Explanation   1+

2: Description   1+

1: Exploration   1