If a researcher wants to use an interrupted time series design to examine whether lowering the legal limit of blood alcohol level (BAL) for driving under the influence affects the frequency of arrests, the researcher would:
A)compare a state with a higher BAL to one with a lower BAL.
B)measure the number of arrests just before and immediately after a law lowering BAL.
C)measure an extended period of time before and after a law lowering BAL.
D)correlate the amount of alcohol consumed by an individual and the number of times they have been arrested.

Question

Quizplus · Accepted Answer

The interrupted time series design involves collecting data over an extended period of time both before and after the implementation of a policy or intervention. In this case, the researcher would measure the frequency of arrests for driving under the influence both before and after the legal limit of blood alcohol level is lowered. This design would allow the researcher to assess whether there was a significant change in the frequency of arrests immediately following the change in policy, and whether any changes persisted over time. Comparing states with different legal limits (A) may introduce confounding variables that could invalidate any conclusions, while measuring individual alcohol consumption and arrest frequency (D) may not be feasible or realistic.

If a Researcher Wants to Use an Interrupted Time Series