This study was conducted from March through May, 2007. The sampling and observation method for the present study is designed to be generally comparable to the 1995 study while incorporating some adjustments. The general approach to the design is to sample from every county in the state, to distribute observation sites across counties according to their population, to select locations where traffic must come to a complete stop in order to allow observation of both front-seat and rear-seat child restraint details, and to select a mix of signalized (RGA) intersections and stop-sign-controlled intersections according to their traffic volume. This probability-based sampling method was utilized to select 86 intersections for observation, including 62 signalized intersections and 24 stop-sign intersections. As in the earlier studies, visual observations were made to determine the extent of use.
Leighton, Al BA and Dodge, Jen, "Child Safety Restraint Use in Maine 2007" (2007). Children, Youth, & Families. 44.