In a previous correlational study, Dr. Lafayette has found that owning dogs is associated with lower levels of daily stress in a sample of returning war veterans. Which of the following would constitute a shift from theory-testing mode to generalization mode? A. Conducting a study on the same sample of war veterans, this time using a different measure of stress.
B. Conducting a study examining the stress reduction in dogs.
C. Conducting an experimental study in which he assigns people to own a dog or not.
D. Conducting a study on dog ownership using a sample of elderly participants from a local retirement home.

D). Conducting a study on dog ownership using a sample of elderly participants from a local retirement home.

Explanation:

Theory-testing mode aims to assess the association and causal claims in order to look for support for a theory. Hence, it lays more emphasis on external validity instead of internal rationality. While the generalization mode focuses on generalizing the findings discovered from distinct samples and procedures of the study to a wider context or population.

As per the question, the 'conductance of a study on dog ownership through a sample of elderly participants from a local retirement home' exemplifies that the theory-testing model is being shifted to generalization mode as it is trying to generalize the findings(from samples) by associating it to a wider context(population). Thus, option D is the correct answer.