Multivariate relationships between self-reported speeding, self-

For exploratory purposes, it was decided to conduct an additional logistic regression analyses to identify what factors distinguished between those participants who reported never engaging in either drink driving or speeding, compared to those who reported engaging in both behaviours, thus representing a high-risk group, see Table 4.28. In order to conduct this analysis it was necessary to identify two groups of participants based on their responses to questions regarding their drink driving and speeding behaviour. The first group (n = 339, 72.7%) were those who responded that they ‘never’ drove when they may have been over the legal BAC limit and did not exceed the posted speed limit by 10 kilometres per hour or more. It should be noted that this group includes those who indicated that they may have exceeded the posted speed limit by up to 10 kilometres per hour. However, as discussed in section 2.2.1, many drivers believe that there is an enforcement tolerance with regard to speed limits and therefore exceeding the posted speed limit by this amount does not

constitute non-compliance with law. The second group (n = 127, 27.3%) were those who indicated that they may have driven when they were over the legal BAC limit and engaged in any level of speeding behaviour. The categorisation of participants into these groups was undertaken to contrast the factors contributing to more deviant road use (i.e., both drink driving and speeding), compared with more compliant driving behaviour. Please note that expanded deterrence theory and social learning theory were operationalised for both speeding and drink driving behaviour, thus both sets of predictors were utilised in this analysis.

The first block encompassed sociodemographic and legal factors, as operationalised by expanded deterrence theory. It was found that this group of

variables significantly predicted higher levels of deviant self-reported speeding and drink driving behaviour, χ² (25) = 125.77, p <.001, Nagelkerke R² = .34. The second block entered both the person-related factors, and psychosocial factors, as captured by Akers’ Social Learning Theory. The second block of variables was found to be significant, χ² (50) = 73.69, p< .001. In addition the Nagelkerke R² was significantly higher for the full model encompassing person, legal, and social factors than the sociodemographic and legal factors model (51 percent versus 34 percent), indicating a stronger association between the full model and higher levels of deviant self-reported speeding and drink driving behaviour.

Within the final model there were several predictors that were found to

significantly predict higher levels of deviant self-reported speeding and drink driving behaviour. For instance, the experience of direct punishment avoidance for both speeding and drink driving was found to be significant. However it was noted that direct punishment avoidance for speeding was associated with a decreased likelihood [O.R. = .95, 95% C.I. = .90 to 1.00] of being categorised into the more deviant speeding and drink driving group. In the case of drink driving, direct punishment avoidance was associated with an increased likelihood [O.R. = 1.10, 95% C.I. = 1.06 to 1.15] of being categorised into the more deviant speeding and drink driving group.

It was also found that having a family member convicted of drink driving was associated with an increased likelihood [O.R. = 2.32, 95% C.I. = 1.13 to 4.75] of being categorised into the more deviant speeding and drink driving group.

Of the three person-related factors entered into the model, only the Bortner Type-A Behaviour Patter scale and the AUDIT scale were found to be significant predictors of higher levels of deviant self-reported speeding and drink driving behaviour. Specifically, on the Bortner Type-A Behaviour Pattern scale, increased

scores were associated with an increased likelihood [1.03 times, 95% C.I. = 1.01 to 1.05]; and on the AUDIT scale, it was similarly found that increased scores were associated with an increased likelihood [1.12 times, 95% C.I. = 1.05 to 1.19] of being categorised into the more deviant speeding and drink driving group. Among the social learning factors, it was found that favourable personal definitions held by the individual toward speeding [1.04 times, 95% C.I. = 1.00 to 1.08] and drink driving behaviour [1.06 times, 95% C.I. = 1.02 to 1.11] both increased the likelihood of being categorised into the more deviant speeding and drink driving group.

Table 4.28

Sequential logistic regression analysis of self-reported frequency of speeding and drink driving as a function of sociodemographic, deterrence theory, social learning theory, and person related factors (N=466)

B S.E. Wald O.R. 95% C.I. O.R.

Legal Factors – Drink driving

Direct exposure to punishment -1.10 0.72 2.33 0.33 0.08 1.37

Exposure to enforcement 0.00 0.12 0.00 1.00 0.79 1.26

Personal knowledge of sanctions 0.00 0.05 0.00 1.00 0.91 1.09

B S.E. Wald O.R. 95% C.I. O.R. Diff Assoc – non-compliance beh

friend

-0.12 0.16 0.64 0.88 0.65 1.20

Diff Assoc – non-compliance beh family Diff Assoc – non-compliance beh

friend

-0.02 0.12 0.03 0.98 0.78 1.23

Diff Assoc – non-compliance beh family

4.9 Chapter summary

This chapter has presented a quantitative examination of a broad range of factors contributing to self-reported frequency of speeding and self-reported frequency of drink driving. Included within the theoretical framework were psychological, legal, and social factors associated with these two behaviours. The aim of the research was to determine the relationship between the two behaviours and whether there were any similarities or differences in the factors that contribute to a driver’s decision to engage in either speeding or drink driving.

The chapter has examined both the bivariate relationship between the theoretical constructs and the behaviours under review. Further, it has also

documented a series of regression analyses investigating the factors that predict self-reported speeding, self-self-reported drink driving, and those who are willing to engage in both behaviours. In relation to self-reported speeding, three separate multiple

regressions were undertaken to look at the predictors associated with speeding up to 10 kilometres per hour, speeding 10 kilometres per hour or more, and for a measure of global self-reported frequency of speeding. A full discussion of these results will follow in Chapter Five.

Chapter Five: Discussion 5.1 Introduction

The findings discussed in this thesis represent a comprehensive examination of the wide range of factors that may influence a driver’s decision to exceed the posted speed limit and to drive while over the legal BAC limit in Queensland. This section provides a review of the findings and the level of support for the individual

hypotheses and research questions.