A small town decides to ban cell phone texting while driving. Before putting the law into effect, officials measure the amount of cell phone use among drivers by placing observers at a busy intersection and recording the percentage of drivers using phones. They do this over 6 consecutive one-week intervals, each week being the middle week of a month i.e., six months of pretesting). Right after the law is passed, officials repeat the observational study for another six months. Which of the following is true about the design of this study?
A) it is an interrupted time series design
B) it is an example of a nonequivalent control group design
C) without a control group, there is no way to evaluate trends with this design
D) because there are multiple observations this would qualify as a regression discontinuity design

Question

Quizplus · Accepted Answer

This study is an example of an interrupted time series design because it involves repeated observations over time before and after an intervention (the law banning cell phone texting while driving).

A Small Town Decides to Ban Cell Phone Texting While