Ch. 9

Question 1

Experimental study

Answer 1

Manipulates the independent variable to measure changes in the dependent.

Test cause and effect relationships.

Cochran’s level 2 (RCT’s) and 3 (quasi)

Question 2

Quasi study

Answer 2

Test cause and effect by manipulating the independent.

Randomization may not be possible and may not be a control group (less convincing).

Provides cochrane level 3

Question 3

Non-experimental design

Answer 3

Examines factors involved in a phenomenon.

Explore events, people, or situations as they normally occur.

Does not manipulate variables.

Tests relationships and differences between variables.

Level 4

Question 4

What is the purpose of random assignment?

Answer 4

Tries to balance any intervening variables that may come about in a study