HOME-STUDY DRIVER EDUCATION
of knowledge. It also serves as a gauge of the overall precision of the exam as a measurement instrument. Coefficients closer to 1 are more desirable and .70 is commonly considered to be a minimum standard. The internal-consistency reliability of the knowledge questions on Form 1 of the exit examination was .49 based on data from 21 novice students in the second pilot study in February 2001. This low reliability coefficient was expected, given that the students did not have prior instruction in the content areas. A Cronbach’s internal-consistency reliability coefficient of .67 was obtained for the students participating in this evaluation, indicating fairly satisfactory reliability. Forms 2 and 3 of the exit examination knowledge items and their accompanying item statistics were archived in case additional versions of the exit examination were needed during the course of the study because of breeches in test security, but it did not become necessary to use these additional forms.
Crash Proneness Internalization (CPI) Attitude Items It was suggested long ago that intrinsic personality factors, such as perceived locus of control, might be a better criterion for evaluating driver education effectiveness than crash rates (Page-Valin et al., 1977). Locus of control refers to the degree to which people believe that the outcomes of life events they experience, such as being involved in crashes or receiving traffic tickets, are under their personal control or primarily due to chance factors (Rotter, 1966). Student attitudes about safe driving were measured using the CPI scale, which was created for use in this study. The CPI consists of 15 items created to measure driver attitudes that were modeled after Montag and Comrey’s (1987) Driving Internality (DI) and Driving Externality (DE) Scales. The DI and DE scales were created to measure the extent to which individuals attribute crash involvement to themselves (DI) or to outside factors (DE). These driving-specific scales were created because researchers in other areas have achieved more success in relating locus of control to their specific areas of research when the items were modified to more specifically target the area (Montag & Comrey, 1987). The DI and DE scales’ authors demonstrated that having more of an internal locus of control (DI) was associated with lower involvement in fatal crashes and having more of an external locus of control (DE) was associated with higher involvement in fatal crashes. A similar measure was successfully used by Gebers (1995) to measure attitude change for traffic violator school attendees, although subsequent correlations with crash and violation rates indicated small, non-significant relationships. Additional evidence for the relationship between crash proneness and locus of control comes from Jones and Wuebker (1985, 1988, 1993), who found that having more of an internal locus of control was associated with lower levels of job-related accidents, including those for bus drivers. Internal locus of control has also been shown to be related to lower crash propensity (Mayer & Treat, 1977), injuries (Sherry et al., 1996), employee accidents (Hansen, 1988, 1989), and injury-prone behavior (Marusic, Musek, & Gudjonsson, 2001).
Each of the 15 CPI items presents a driving-related attitude at one extreme of locus of control, such as “Crashes occur because drivers don’t drive as safely as they should.” Respondents were asked to indicate the extent to which they agree with each item on a 6-point scale ranging from 1 (Strongly Disagree) to 6 (Strongly Agree). Higher numbered responses indicate more of an internal locus of control for Items 1, 2, 4, 5, 7, 10, 12, 13, and 14. Items 3, 6, 8, 9, 11, and 15 are worded so that higher response values indicate a higher external locus of control and therefore needed to be recoded before calculating a total score of the attitude items. Total scores were calculated by summing responses to