True Experiments vs. Quasi-Experimental Designs What Qualities

¶ … True" Experiments vs. Quasi-Experimental Designs

What qualities of the quasi-experimental design are evident in this study?

This study was specifically designed to test the efficacy of a new program designed to improve police responses to cases involving domestic violence. Through the Second Responders Program, trained social workers would follow police after domestic violence-related calls and provide victims with counseling and information about social support services if the victims wished to leave their abusive partners. To evaluate the program, "field researchers contacted eligible subjects and attempted to interview them within 1 week of the domestic violence incident to which police were called; the second interview took place 6 months later" (Lane et al. 2004: 4).

Because the city of Richmond implemented the Second Responders Program in only two of its four police precincts, the researchers chose to use as a control group the precincts where the program was not implemented. The experimental group consisted of the precincts were the program was implemented; the control group consisted of the precincts where the program was not implemented. Because the different precincts were within a relatively similar geographic range, they were deemed to be similar enough to warrant a comparison. The same criteria for domestic violence was used when comparing the results of the interviews of both groups and "only cases that occurred during the Second Responders' working hours -- 6 p.m. To 9 a.m. -- were included to ensure experimental and control group comparability" (Lane et al. 2004: 4). Additionally, only female subjects over the age of 18 were compared in both groupings, to ensure demographic homogeneity. Thus although the groups were not part of a randomized control experiment, considered the 'gold standard' of clinical validity in experimental design, the similarities between the two groups were designed to ensure that the control group was relatively representational.

Q2. Why didn't the researchers choose to use a "true" experimental design?

A true, perfectly controlled experimental design would have been logistically impossible. The program being studied was a 'real world' program specific to an area of the country -- it would have been impossible to randomly assign different domestic violence complaints to the Second Response team. The program was concentrated in a specific geographic area. Thus the quasi-experimental design of using a neighboring area as a control group was the only option.