REPORTED ATTITUDES, PRACTICES AND KNOWLEDGE IN RELATION TO DRINK-DRIVING: THE EFFECTS OF THE INTRODUCTION OF RANDOM BREATH TESTING IN NEW SOUTH WALES

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1 REPORTED ATTITUDES, PRACTICES AND KNOWLEDGE IN RELATION TO DRINK-DRIVING: THE EFFECTS OF THE INTRODUCTION OF RANDOM BREATH TESTING IN NEW SOUTH WALES * R. F. S. Job, B.A. SYNOPSIS Random breath testing (RBT) was introduced in New South Wales in December 1982 and caused a substantial reduction in fatal and injury crashes. Similar results have been achieved elsewhere. However, little is known of the mechanism(s) by which this change in driver (and motor cycle rider) behavior is achieved. To examine the effects of RBT and associated publicity campaigns 2 door-to-door surveys of 1,000 Sydney licensed rider/drivers were conducted: the month before the introduction of RBT and 5 months after its introduction. The results are discussed in terms of social approval and morality in relation to drink-driving, acceptance of the law and RBT, knowledge of the law, knowledge of alcohol, and drink-driving practices. INTRODUCTION Drink-driving has been recognized as a major contributor to road trauma in New South Wales (Herbert, 1980). Australia is, in general, a high realcohol-consumption country: it ranks in the 10 highest per capita consumption countries in the world, and is highest of the world's English speaking countries (Moon, 1975). To combat the drink-driving problem, random breath testing (RBT) was introduced on a trial basis by the Government of the State of New South Wales on December 17, A major publicity campaign based on the theme, J'How will you go when you sit for the test? Will you be under.05 or under arrest? accompanied the introduction of RBT, and is regarded as parte of RBT, for this report. Goldsmith (1983) presented strong evidence to indicate that RBT caused a statistically significant reduction in fatal road accidents from December 1982 to February The reduction appears to have continued. Based on the preliminary figures of fatalities from December 17, 1982 to September 30, 1983, there were 746 road accident deaths in New South Wales. Assuming a continuation of pre-rbt trends, * Traffic Authority of New South Wales, P.O. Box 110, Rosebery, N.S.W. 2018, AUSTRALIA. 707

2 the estimated number of deaths, based on the last 6 years, was 1,020 for the period. This represents a saving of 274 lives and a reduction in fatalities of 26.9%. However, experience in other countries (especially France) indicates that the effect of similar measures has been relatively short lived (Ross, 1981). Ross speculated that with experience the motorist learns that the actual risk of being detected for drink-driving is not as high as first expected under RBT. Thus the effect dissipates. Homel (1983) predicted that this would also be the case with RBT in New South Wales (N.S.W.). However, the operation of RBT in N.S.W. has emphasized high visibility to the motoring public via the sheer visual impact of the large buses and flashing blue lights used at metropolitan RBT roadside stations. The associated media campaign was also carefully designed to provide a more effective low-level threat appeal (Kohn et al., 1982). In other words, rather than attempting to present the high fear-arousing consequences of drink-driving, such as a fatal or serious crash or even the maximum penalties for drink-driving, the campaign simply concentrated on the consequence of actually being apprehended and arrested by the police. The specific penalties were only a minor part of the campaign. The second campaign, conducted in April 1983, presented the same message. Homel (1983) presented data on attitudes to RBT and drink-driving based on a survey in February However, Homel's sample included only 254 license holders who drank at least once a year. Further, no direct before/after measurements were possible in Homel's study; rather, respondents were asked a particular question and then asked how they thought they would have answered that question if asked on the day RBT was introduced. Such a procedure is subject to criticism since the results rely on the accuracy of the subject's memory and the procedure may contain experimenter demand to make the 2 answers different (Orne, 1962; Patty & Page, 1973; Rosenthal, 1966). Nonetheless, this was perhaps the best procedure available given that Homel had not been able to make measurements prior to RBT. The study being reported here was conceived before it was certain that RBT was to be introduced. When the proposed date of introduction of RBT was announced, plans were accelerated to allow a first survey to be held in November 1982 before RBT actually began. Hence a pre-rbt baseline was established against which future survey results could be compared. 708

3 The study examined drivers' (including motorcyclists') attitudes, knowledge, and behavior in relation to drink-driving. One aim was to determine the nature of any change in people's attitudes and behavior which might have led to the dramatic reduction in crashes following the introduction of RBT. The other major aim was to determine whether the effect of RBT was associated with an increase in the perceived risk of detection while drink driving. METHODS Interviews with a total of 1,981 drivers who had consumed alcohol in the last year, were included in the study: 993 in the sample prior to RBT (henceforth called "the pre-rbt survey") and 988 in the sample surveyed after the introduction of RBT (henceforth, "the post-rbt survey"). A further 298 interviews were begun but terminated because the respondent was either not a driver or had not consumed alcohol within the last year. Respondents were contacted in their homes; they were selected on a random basis at the home within the criteria that equal numbers of respondents be male and female and that in the total sample equal numbers were obtained from the following 7 age groups (in years at their last birthday): 17 to 19; 20 to 24; 25 to 29; 30 to 39; 40 to 49; 50 to 59; and 60 to 69. If no-one was at home, or if the selected respondent for the household was not home, interviewers were instructed to call back once before abandoning that respondent. The samples for the 2 surveys were selected from the same 100 start points within the Sidney metropolitan region. (Sydney is the largest city in N.S.W. Of the total reported crashes in the state, 58% occur in Sidney, as do 32% of road deaths and over 50% of injuries.) The interviewers moved to the left of the start point in one survey and to the right in the other survey. Thus, the same households were not visited in both surveys, yet the same areas were surveyed. The pre-rbt survey was conducted in November 1982 and the post-rbt survey was conducted in May Respondents in the first survey were asked 40 questions on their attitudes to and knowledge of the law, and their knowledge of alcohol and its effects. Respondents in the second survey were asked the same 40 questions, with the exception that the question on RBT was changed from future to past tense. An additional 9 questions on the operation and penetration of RBT were added at the end of the second survey. 709

4 In the pre-rbt survey the 6 male and 17 female interviewers' ages ranged from 21 to 60 years. In the post-rbt survey 10 male and 22 female interviewers were employed, with an age range of 24 to 60 years. Twelve interviewers employed in the pre-rbt survey were also used in the post-rbt survey. Further details of the survey methodology have been provided by Job (1983 a). STATISTICAL ANALYSIS Differences between the pre-and post-rbt survey results were tested using the Chi-squared statistic. The alpha rate was set at.05. Due to the sampling technique used, which required equal numbers of interviewers with respondents in. the 7 specified age ranges, weightings were necessary to obtain an estimate of the opinions of the general population of drivers. For example, approximately 7.14% of the sample was obtained from each age group in each sex, yet males aged 30 to 39 accounted for 14.4% of the population holding driving and/or riding licenses in N.S.W. within the total age range sampled (17 to 69). Therefore, the responses of 30-to-39 year-old males were weighted so that their relative importance was increased by a factor of approximately 2 in order to calculate the response of the licensed population. In presenting the results the actual percentage of the sample giving a particular reply is given, with the calculated percentage of the licensed population for that reply given in parentheses immediately after the sample percentage. (Note that with this weighting we assume that similar proportions of license holders were rejected from the sample in all age and sex categories because they drank alcohol less than once per year.) Penetration of RBT RESULTS AND DISCUSSION In May 1983, 62.6% of drivers reported having seen an RBT station in operation. More males reported having seen a station than females (12.6 percentage points difference; Chi-squared = 10.9, degrees of freedom [df] = 1, jd less than.001). Although some interviewers may have mistaken other police operations for RBT or were exagerating, this high level of visual penetration indicates that the highvisibility strategy adopted in the operation of RBT had been successful. Furthermore, 18.6% of the post-rbt sample reported having been in a car stopped at an RBT station. 710

5 There was a marked increase in the number of respondents reporting that they knew someone (including themselves) who had been breath tested. In the pre-rbt survey 52.8% reported knowing someone who had been tested, compared with 70.3% in the post-rbt survey. This increase was statistically significant (Chi-squared = 64.6, df = 1, less than.001). There was also an increase in the number of people reporting that they had themselves been breath-tested. In the pre-rbt survey 13.3% reported having been tested, compared with 19.3% in the post-rbt survey (Chi-squared = 13.3, df = 1, p is less than.001). Allowing for some drivers being tested previously and some drivers being tested more than once at RBT stations, the increase of 7.8 percentage points in the licensed population claiming to have been tested is consistent with police reports of having tested 195,239 drivers in the Metropolitan area from December 17, 1982 up until May 28, 1983). This would represent 11.2% of the licensed drivers; however, a very small number of those tested were not licensed to drive. Deterrence of Drink-Driving by RBT Most people felt that the chances of being charged for drink-driving had risen with the introduction of RBT: 26.5% felt the chances were much higher; another 50% felt they were higher; 17.6% felt they were about the same; and 5.9% felt the chances had dropped. This question was only asked in the post-rbt survey. Respondents in both surveys were asked whether they were more deterred from drink-driving by the possibility of an accident or by the possibility of being stopped by the police. Consistent with the above result, there was a marked increase in those reporting that they were more deterred by possible police action. The percentage rose from 33.6% to 47.1% with a commensurate drop in those more deterred by possible accidents, and a very small number (less than 1%) reporting that they were not deterred by either possibility. The change from pre-rbt to post-rbt was significant (Chi-squared = 42.85, df = 2, less than.001). It remains to be seen whether this deterrent effect will be maintained. The deterrent effect of RBT is perhaps slightly weakened by the perceived possibility of avoiding being stopped. In the post-rbt survey, 33.0% of interviewers believed that there was action they could take, while driving, to decrease their chances of being stopped at an RBT station. Further questioning of these drivers 711

6 revealed that the most common avoidance methods suggested were (a) use of back streets for the journey, with 34.8% suggesting this method, and (b) use of side streets to avoid the RBT station, with 22.5% suggesting thus action. Other suggestions included stopping, changing lanes, making a U-turn, changing drivers, and avoiding frequently-used locations. No answers were offered by the interviewers; the question was open-ended. Drink-Driving Behavior In reply to the question, "How often have you driven after drinking more than a safe amount of alcohol?", many people admitted to drink-driving (see Table 1). The actual percentages in the sample were similar, to the weighted percentages.) Analysis revealed that a significant decrease in drink-driving was reported (Chi-squared = 7.44, df = 2, less than.05). This is consistent with the increase in deterrence by police action since the introduction of RBT. Table 1; Weighted Driving Population Percentage Reporting How Often They Drove After Drinking An Unsafe Amount Pre-RBT Post-RBT (n = 993) (n = 988) Never Less than or about once a month More than once a month Not known 0 0 Respondents were also asked what they would do about transport after a wedding at which they knew beforehand there would be plenty of alcohol. Eight alternative behaviors were offered. One alternative was to make arrangements beforehand to avoid having to drive home. As 712

7 this alternative requires that action be taken before the wedding it indicates responsible behavior. Other alternatives indicated less responsible behavior such as: drink then drive home carefully; decide at the end of the evening if you can drive; and limit your drinks then drive home. The alternative, "someone else always drive," was regarded as neutral and was not included in the statistical treatment. Chi-square analysis revealed a significant shift away from the less responsible behaviors towards making prior arrangements for transport (Chi-squared = 13.0, df = 1, less than.001). (See Table 2). Table 2: Percentages of Reported Behaviors Regarding Transport After a Wedding Pre-RBT Post-RBT (n = 993) (n = 988) Prior planning to avoid driving Less responsible behaviors Neutral responses No response 0 0 Knowledge of the Law and Drink-Driving The request to state the legal limit for blood alcohol concentration for driving in N.S.W. revealed that a substantial increase in the number of people able to identify the.05% limit had occurred with the introduction of RBT. In the pre-rbt survey 62.6% were correct, whereas in the post-rbt survey 75.4% ((80.2) were correct (Chi-squared = 69.83, df = 1, less than.001). Overall, male drivers were slightly superior to females in their knowledge of the limit (14.9 percentage points difference in the pre-rbt survey, and 9.6 in the post-rbt survey). 713

8 The survey also included questions on the number of drinks which the average person could consume without reaching the legal limit. (See Table 3. The actual sample results were quite similar to the estimates presented.) The statistical analysis revealed that for all 3 drinks (beer, wine, and spirits) there was a significant decrease in the estimated number of drinks before reaching the legal limit (Chi-squared were, respectively, 45.7, 16.6, and 13.1, df = 2, less than.005 in all cases). Table 3: Weighted Population Estimates of Drivers Estimates of How Many Drinks Beer Pre-RBT (n = 993) Post-RBT (n = 988) Number of Middies (230 m l ) Male Female Total Male Female Total greater than don't know Wine Glasses (115 ml) Pre-RBT (n = 993) Post-RBT (n = 988) Male Female Total Male Female Total greater than : don't know

9 Spirits Nips (29 ml) Pre-RBT (n = 993) Post-RBT rn = 988) Male Female Total Male Female Total greater than don't know However, knowledge of alcohol in relation to the legal limit was often poor; many people believed that a middy of beer or a glass of wine is not as intoxicating as a nip of spirits, as reflected in the more.liberal estimates given for wine and beer, compared to spirits. In fact, the 3 drinks in the quantities mentioned, contain approximately the same amount of alcohol. Furthermore, the most common answer for beer and wine was 3 drinks before reaching the limit. This is inconsistent with advertising campaign advice on the matter, which suggests that by consuming 3 drinks in 1 hour you could exceed the limit. Estimates of the number of drinks were still quite excessive in some cases, with some people believing that the average person could consume 10 middies of beer or 6 nips of spirits or 7 glasses of wine and remain below the legal limit. Attitudes to Breath Analysis and RBT The introduction of RBT was associated with a significant increase in the number of people who regarded the breathanalyzer as a good test of blood alcohol concentration. In the pre-rbt survey 68.6% answered that it was a good test, compared with 75.4% in the post-rbt survey (Chi-squared = 14.39, df = 2, less than.001). A different result occurred when interviewers were asked whether they thought the breathanalyzer was a good test of a person's fitness to drive after drinking. Fewer people were satisfied with the breathanalyzer on this criterion, and no significant change occurred with the introduction of RBT. In the pre-rbt 715

10 survey 58.1% felt that the breathanalyzer was a good test of fitness to drive, compared with 58.9% in the post-rbt survey (Chi-squared = 0.21, df = 1, greater than.05). Approval of RBT itself rose from already high levels before its introduction % of drivers in favor - to 85.3% in favor in the post-rbt survey (Chi-squared = 120.4, df = 1, less than.001). A clear majority agreed with the introduction of RBT in each age group in both sexes; in the post-rbt survey the lowest agreement rate was in the 50 to 59 year-old males of whom 72.1% agreed with the introduction of RBT. Moral Values Regarding Drink-Driving One question related to a driver who often drove after drinking too much and who had a serious accident while drink-driving. Respondents were asked to classify this driver as "unlucky," "stupid," "irresponsible," "criminal," or a "potential murderer." Most respondents in both surveys classified the driver as irresponsible or worse. The overall results indicated no significant change with the introduction of RBT (Kruskal-Wallis Test - [see Seigel, 1956]: H=0.09, df = 1, greater than.05), and no reduction occurred in the number of respondents describing the driver as unlucky (Chi-squared = 0.94, df = 1, greater than.05). In another question a driver was again described as often driving after drinking too much, and was on such an occasion stopped for an offense and found to be over the legal limit. Respondents were again asked to classify the driver on the same categories as before. For half the respondents this question occurred immediately after the other similar question, whereas for the other half the order was reversed. In both the pre-and post-surveys the majority of respondents again classified the driver as irresponsible or worse. The results again indicated no significant overall trend towards more disapproving descriptions of the drink driver with the introduction of RBT (Kruskal-Wallis Test: H=0.84, df = 1, greater than 0.05). These results in themselves did not indicate a shift to greater moral disapproval of drink driving. Note, however, that not all the response categories (Table 4) are of the same nature. The category "unlucky" in particular can be contrasted with the other categories: all of the categories other than unlucky designate socially undesirable characteristics, but unlucky is not normally taken as a characteristic of the person at all: that is, a shift from 716

11 unlucky to some other category implies, to this extent, greater blame of the individual. In accordance with these considerations, an analysis was made of the extent to which responses had moved from "unlucky" to some other category and found, indeed, a significant decrease in the number of respondents describing the driver as unlucky (Chi-squared = 5.73, df = 1, less than 0.02). Table 4: Disapproval of a Drink-Driver Involved in a Serious Crash and a Drink-Driver not Involved in a Crash in Weighted Percentages for Each Description Crash- -Involved Pre-RBT (n=993) Post-RBT (n=988) Not Crash i-involved Pre-RBT (n=993 Post-RBT (n=988) Unlucky Stupid Irresponsible Criminal Potential Murderer No valid Response Traffic Law in General To assess the possibility that the introduction of RBT had significant effects on attitudes and behavior in relation to other aspects of traffic safety, questions were asked on seat belts and radar speed checks. When asked how often they wore their seat belt, 88.3% replied "always," 6.8% agreed to "mostly," with the remainder reporting "occassionally," "rarely," or "never." These results did not change significantly with the introduction of RBT: in the after survey 88.5% reported "always" and 7.3% reported "mostly." Although self-reported seat belt usage has been 717

12 shown to be unreliable (Job, 1983), these reported usage rates are only slightly higher than the 87% use by drivers recorded in roadside surveys in Sydney in 1982 (Schnerring & Norrish, in preparation). Note that seat-belt use is compulsory in Australia. The number of people in favor of the use of radar speed checks increased significantly after the introduction of RBT. Before RBT 63.0% favored their use, whereas after RBT's introduction 75.2% were in favor (Chi-squared = 6.94, df = 1, less than.01). The increase in popularity of radar was similar in male and female drivers. It is striking that approval of this police activity increased with the introduction of RBT. CONCLUSIONS The RBT has had a, substantial impact on drivers in N.S.W. and has been accompanied by a dramatic reduction in the road toll. Most drivers report having seen RBT in operation, and many thousands have been tested. A decrease in reported drink-driving and an increase in planning of transport alternatives to driving have also occurred since the introduction of RBT. The results of the presently-reported surveys indicate that the reduction in drink-driving has been due, at least in part, to the perceived increase in probability of being stopped by the police. This deterrent effect could perhaps be further increased by decreasing the belief held by many that there are certain actions a driver can perform to lessen his or her chances of being stopped at an RBT station. Disapproval of the drinking driver also appears to have increased, with a shift away from regarding the driver as unlucky if caught by police, and a commensurate increase in those regarding such a driver as stupid or worse. The RBT and the associated media campaigns have also led to an improved knowledge of the.05% limit. In addition, it has caused a more conservative attitude towards alcohol. Overall, estimates of the number of drinks the average person can consume before reaching the legal limit has decreased. However, the large proportions of drivers who still believe that 3 drinks, particularly 3 beers, can safely be consumed before driving, strongly indicates that publicity and education on this subject has not been as effective as was hoped. 718

13 The RBT is now a very popular road safety measure but the cornerstone of RBT, the breathanalyzer machine, has a relatively poor image, particularly as a means of testing for fitness to drive. It is not clear, however, whether this detracts from the popularity of RBT or, more importantly, from the effectiveness of RBT legislation as a deterrent to drink-driving. A somewhat more surprising effect of RBT has been to cause an increase in the popularity of radar speed checks. This may reflect a generally improved attitude to road safety and/or to the police. The fact that there was no change in the reported wearing rate of seat belts lends mild support to the view that the main change has been in relation to attitudes to the police. The possibly improved attitude to the police may reflect the public's increased exposure to the police under the circumstances of not being in breach of the law. Previously, many drivers' only contact with the police was when they received a fine for a traffic offence. That pairing of events could not be expected to create a positive attitude to the police. The media campaign, which was designed with the public-image of the police in mind, may also have helped to improve community support for police enforcement efforts. ACKNOWLEDGEMENTS This report is based on research conducted while the author was a Behavioral Scientist in the Traffic Authority of New South Wales. The author gratefully acknowledges the assistance of the Traffic Accident Research Unit of the Traffic Authority, and in particular Ms. H. Goldsmith, Mr. A. Graham, and Ms. H. Papatheodorou for help with data collation and statistical analysis, Dr. H. Papatheodorou for help with data collation and statistical analysis, and Dr. R. Arthurson and Mr. B. Vazey for helpful comments on the manuscript. Any views expressed in the report are those of the author and are not necessarily endorsed by the Traffic Authority. REFERENCES Goldsmith, H. (1983). Evaluation of Random Testing; Preliminary Analysis of Fatality Data. Report WAR 83/1. Sydney; Traffic Authority of New South Wales. Job, R.F.S. (1983 a). The effects of Random Breath Testing on attitudes knowledge and behavior. Paper presented at the Behavioral Medicine Conference, Cumberland College of Health Sciences, Sydney. (Proceedings in Press.) 719

14 Job, R.F.S. (1983 b). The Use of Seat Belts and Child Restraints; Survey Methodology. Report RN 3/83. Sydney: Traffic Authority of New South Wales. Herbert, D.C. (1980). Road Safety in the Seventies: Lessons for the Eighties. Traffic Accident Research Unit Report RR 4/80, N.S.W. Sydney: Department of Motor Transport. Homel, R. (1983). The impact of random breath testing in New South Wales, December 1982 to February Medical Journal of Australia, _1, Kohn, P.M., Goodstadt, M.S., Cook, G.M., Sheppard, M., and Chan, G. (1982). Ineffectiveness of threat appeals about drinking and driving. Accident Analysis & Prevention, ^4: Moon, J.R. (1976). Alcoholism in Australia in Annals New York Academy of Sciences, 273: Orne, M.T. (1962). On the social psychology of the psychological experiment: With particular reference to demand characteristics and their implications. American Psychologist, 17: Patty, R. A., and Page, M.M. (1973). Manipulations of a verbal conditioning situation based upon demand characteristics theory. Journal of Experimental Research in Personality, 6^: Rosenthal, R (1966). Experimenter Effects in Behavioral Research. New York: Appleton-Century-Crofts. Ross, H.L. (1981). Deterring the Drink-Driver: Legal Policy and Social Control. Lexington, Massachusetts: Lexington Books. Scherring, F.W., and Norrish, J.K. (in preparation). The Use of Occupant Restraints in Sydney, 1982 and 1983, Traffic Authority of New South Wales Research Note. Siegel, S. (1956). Non-parametric Statistics for the Behavioral Sciences. New York: McGraw-Hill. 720