Table 9.2 Selected Types of Group Research Designs Commonly Used in Program Evaluation Studies

±±±±±±±±±±±±

Name of Design Notation Pre-experimental Designs 1. One-group posttest-only X O 2. One-group pretest–posttest O X O Quasi-experimental Designs 3. Nonequivalent control group O O

X O O

4. Interrupted time series OOOO X OOOO 5. Multiple time series O O

O O

O O

O O

X O O

O O

O O

O O

Experimental Designs