EVALUATION OF A DRINK DRIVING PUBLICITY CAMPAIGN. * * * C. J. Boughton, M.D. ; and D. R. South, B.A. SYNOPSIS

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1 EVALUATION OF A DRINK DRIVING PUBLICITY CAMPAIGN * * * C. J. Boughton, M.D. ; and D. R. South, B.A. SYNOPSIS A publicity campaign against drink-driving with the theme "What sort of friend are you? Would you let a friend drive if he's had to much to drink?" was pilot tested in Tasmania and Australia using a 2-city cross-over experimental design. Results indicate that the campaign was successful in changing peoples knowledge, attitudes, and behavior in respect of drinking and drink-driving. In 1980/81, the Office of Road Safety of the Australian Government conducted an experimental evaluation of a drink driving campaign (the pilot campaign) that had been developed for use throughout the country. The results of the evaluation were sufficiently encouraging to warrant proceeding to a national campaign, which occurred, approximately 2 years later, in 1982/83. Summary results of the pilot campaign's effectiveness will be discussed here together with the effects of the national campaign. A full report of the development and evaluation of the pilot campaign is being published separately (Elliott & South, 1983). INTRODUCTION Reviews of the research literature and of drink driving campaigns throughout the world reveal a large number of campaigns that have never been evaluated, a small number of campaigns where some attempt at evaluation has been made, and a very few where an evaluation has been conducted and reported finding sound evidence of effectiveness. The key campaigns in the last category were reported by Farmer (1975), Pierce et al. (1975), and Croke (1977). In 1972 a campaign was developed and run for 1 month pre-christmas in Edmonton, Canada using Calgary (some 200 miles away) as a control. A classic pre-test/post-test control group design was used to evaluate the effects. * * * Federal Office of Road Safety, P.O. Box 111, Dickson, ACT 2602, AUSTRALIA. Road Traffic Authority, Victoria, AUSTRALIA. 199

2 Farmer (1975) reported that the criterion of assessment was the distribution of blood alcohol concentrations (BAC's) in randomly selected sample of drivers stopped in roadside surveys. At the same time, drivers were interviewed to assess their knowledge about various aspects of the campaign along with the drivers' attitudes to drink driving laws. The campaign theme was "if you drive after drinking..." and was aimed at giving factual information relating to the problem and suggestions as to how to avoid alcohol-related accidents. The control city, Calgary, ran its usual annual pre-christmas campaigns. Compared to the control city, roadside surveys of knowledge and BAC's showed a drop from 3% to 1.4% in the population of drivers over the legal limit (.08%) and significant improvements in knowledge and attitude accompanying this behavioral change. Farmer (1975, p. 838) concluded that "the Edmonton campaign was effective in reducing the number of impaired drivers (BAC greater than.08%) on the road." He also demonstrated that knowledge and attitudes were changed and public praise for the campaign was outstanding. Pierce et al. (1975) reported on a study in Ontario, Canada which used a before-after design with 9 cities in each of the experimental and control groups. The method of collecting data was a telephone survey of licensed drivers. The authors pointed out that "while it would have been desirable to directly monitor drink driving behavior this was impossible due to severe time constraints" (Piece et al. 1975; p. 872). The content of the campaign, which ran in December 1973 for 4 weeks, was: 1) Positive approach encouraging the use of alternative transportation; 2) Positive approach suggesting limitations for those who will continue to drive after drinking; and 3) Information about the laws, penalties, and consequences of drink-driving. Demographic, exposure, and drinking behavior comparisons were made between control and experimental groups since randomization was not feasible. The telephone survey questionnaire measured exposure, opinion changes, 200

3 knowledge, awareness, and changes in reported behavior. To encourage cooperation each driver selected to participate was sent an advance letter advising about the interview. Of people contacted 95% completed the questionnaire. The campaign was reported as being effective in increasing the number of people who reported not driving home when they were drunk; in informing people of the maximum legal blood alcohol levels and that "jail" was a possible penalty of driving and drinking; and in increasing the number of conversations about drinking and driving (Pierce et al. 1975; p. 879). The National Highway Traffic Safety Administration in the U.S.A. in 1975 and in 1976 released radio and television commercials using the theme "Friends don't let friends drive drunk" for use with the 10 Alcohol Safety Action Projects (ASAP's) extended to 1975/76. Croke (1977) reviewed the evidence, largely derived from extensive and standardized telephone surveys (at 6 and 18 months after the campaign start), on the effectiveness of the 1975/76 extended ASAP's. The conclusion was that people became more knowledgeable about alcohol and its effects and that this knowledge was influenced by ASAP advertising. The order of magnitude of the change was typically around 5%. For example, the proportion of respondents with high total knowledge scores rose from 30% at baseline to 36% in the second following year. In addition to being more knowledgeable, those persons who saw the advertisements were better able to recognize potential drink-driving situations. On attitude change, findings were not clear cut, but some 85% of viewers who saw the advertisements agreed with statements regarding personal responsibility for friends and the need to intervene to prevent drink-driving. This compares with 80% for those who did not see the advertisement. Intervention behavior appeared less easily influenced by advertising. However, when respondents were grouped according to whether they had been exposed to advertising, 72% of advertisement recognizers versus 65% of non-recognizers reported taking intervention actions in the first follow-up survey. Since this difference was gone by the subsequent second follow-up survey, any benefit is likely to have only been in the short term. Reports on extended ASAP's (such as Miller, 1976, for the Los Angeles project and Miles and Clay, 1977, for the Phoenix ASAP) indicate the level of impact of mass media campaigns. In these campaigns the theme concerned the 201

4 responsibility towards friends and possible intervention behavior. From telephone surveys in Los Angeles in 1974 (pre-advertising) and 1975 (post-advertising) there was an increase from 65% to 76% of respondents who felt they could prevent someone from driving after drinking and an increase of 12% in the number of respondents who had actually intervened in such a situation (from 53% to 65%). These results occurred after 14 months of advertising exposure (Miller, 1976). In the 1975/76 Phoenix mass media campaign the proportion of respondents reporting a drink driving situation dropped from 42% to 37% and after the campaign some 10% more respondents indicated they would take steps to prevent drink driving (Miles & Clay, 1977). All of these campaigns involved some positive suggestions relating to alternatives to drink driving. The mass media activities were sometimes only part of a wide range of related countermeasures and in some cases exposure was over a relatively long period of time. However, may such campaigns have small but significant effects on drink driving behavior. THE CAMPAIGN With this background, an Australian campaign was developed following a similar approach based on responsibility towards friends and possible intervention behavior. The campaign used the theme: "What sort of friend are you? Would you let a friend drive if he's had too much to drink?" Four 60-second television commercials featured a popular television actor, Paul Cronin, modeling specific behavior which associates of potential drink drivers were urged to adopt. Prior to the national campaign which occurred in 1982/83, a pilot of the proposed campaign was undertaken in Tasmania, using the 4 television commercials plus radio commercials, press advertisements, bus posters, and a good deal of promotional work by Paul Cronin and a firm of public relations consultants contracted specifically for that purpose. Evaluation of the Pilot Campaign in Tasmania Tasmania, the state chosen for the pilot campaign, is relatively well situated for an experimental approach to measuring the effectiveness of a campaign principally using television. There are 2 major population centers: the 202

5 cities of Launceston and Hobart. These 2 cities are well separated geographically and are served by different mass media due to a natural barrier to transmissions. However, the 2 cities are not well matched: Hobart has a population of 48,000 compared to Launceston's 32,000 or, if using statistical districts, Hobart Statistical District is 172,500 and Launceston Statistical District is 87,000. Hobart has a lower proportion of blue collar workers than Launceston and a higher educational level. For these reasons a classic pre-test/cross-over experimental design was used for the evaluation. The campaign was run for 7 weeks in Hobart but not Launceston, and at a later time run for 7 weeks in Launceston and not Hobart. In any event, the campaign in Hobart went from September 14 to November 3, 1980 and in Launceston from March 29 to May 17, In both cases the campaign comprised 2 bursts of 2 weeks of extensive advertising with a 1-week break in between. Evaluation Criteria The ultimate goal of any drink-driving campaign is a reduction in the number and/or severity of road accidents mediated through the action of drivers who were driving under the influence of alcohol. But accidents, especially serious ones, are relatively rare events. In Tasmania about 100 people are killed on the roads each year and in about 50 of these alcohol is a factor. During the campaign lasting 6 weeks only 6 people would be expected to be killed in the whole of Tasmania in accidents involving alcohol. Changes in alcohol involvement in fatal accidents is, therefore, not a viable criterion measure for the campaign's effectiveness. Given that the campaign objective is to change behavior one could argue that a valid measure of effect is the BAC's of drink drivers obtained from roadside surveys in a pre-test/post-test control design. While in theory roadside surveys represent the most valid and reliable measure of drink driving behavior, in practice they could prove to be obtrusive and create undersirable effects. Roadside testing which involves the presence of police, road blocks, and traffic cues would have an effect in itself in both control and experimental cities. This would be tolerable in cities of reasonable population, as used in the Edmonton study (Farmer, 1975), but the populations of Hobart and Launceston are very small and roadside tests would be extremely visible. Word-of-mouth effects would be likely to also be substantial. 203

6 Accordingly, self-reporting via questionnaires became the criterion measure. Such self-reporting may suffer in terms of both validity and reliability but since the main task is to measure change, problems such as over- and under-stating drink-driving behavior do not invalidate results because they apply to all measures taken. Telephone interviews were used since they permitted good sampling control and had a constant respondent selection process. Further, the data could be collected in an identical way from survey to survey. A total of 4 measures were taken in each city, with telephone surveys being conducted in the campaign (experimental) and control cities before and after each phase of the campain. RESULTS Table 1 gives the number of subjects surveyed on each occasion. Excluding the ineligible groups, 68% of attempts yielded a complete interview. Table 1: Sample Sizes Hobart Launceston Pre 1 Post 1 Post 2 Post 3 Aug 80 Dec 80 Mar 81 June Pre 1 Pre 2 Pre 3 Post 1 Aug 80 Dec 80 Mar 81 Dec Those who in the last month consumed 3 or more drinks away from home were asked how they had traveled home on the most recent such occasion (Table 2) and whether they had driven a car or motorcycle after more than 3 drinks in the past month (Table 3). Tables 2 and 3 show that the incidence of self-reported driving after drinking did go up in Launceston (control city) in the December survey but did not significantly rise in Hobart (experimental city). These differences are statistically significant is less than 0.05). Maybe this can be interpreted as the effects of the campaign; however, no effect was evident when the campaign was run in Launceston. 204

7 Table 2: Means of Transport Home* Hobart Launceston Pre 1 Post 1 Post 2 Post 3 Pre 1 Pre 2 Pre 3 Post 1 Aug 80 Dec 80 Mar 80 June 81 Aug 80 Dec 80 Mar 81 Jun 81 No. asked No. who drove home % who drove home * From most recent drinking occasion in last month. Table 3: Interviewees Driving After More Than 3 Drinks Hobart Launceston Pre 1 Post 1 Post 2 Post 3 Pre 1 Pre 2 Pre 3 Post 1 Aug 80 Dec 80 Mar 81 June 81 Aug 80 Dec 80 Mar 81 Jun 81 No. asked No. who drove % who drove A primary objective of the campaign was to encourage individuals to accept responsibility for the safety of associates who consumed an excess amount of alcohol and intended to drive. Table 4 shows the number of respondents who believe that they could so something to prevent someone else from driving. Table 5 indicates the number of respondents who in the last month claimed to have tried to do something to prevent someone from driving after drinking. 205

8 Table 4: Interviewees Believing Intervention is Possible Hobart Launceston Pre 1 Post 1 Aug 80 Dec 80 Post 2 Post 3 Pre 1 Mar 80 June 81 Aug 80 Pre 2 Pre 3 Post 1 Dec 80 Mar 81 Jun 81 No. asked* No. who believe intervention is possible % who believe * Excludes "dont't know" and "situation would never occur". Table 5: Intervention Behavior Hobart Launceston Pre 1 Post 1 Post 2 Post 3 Pre 1 Pre 2 Pre 3 Post 1 Aug 80 Dec 80 Mar 80 June 81 Aug 80 Dec 80 Mar 81 Jun 81 No. asked No. of tiers % trying

9 DISCUSSION A major problem in interpreting the results is that alcohol consumption, and the involvement of alcohol in accidents, is much higher in the December quarter than in the rest of the year. The estimated value of retail sales of beer, wine, and spirits in Tasmania, given in Table 6 by quarter of the year, illustrates the significant increase in alcohol sales (a proxy variable for consumption) in the December quarter each year. Fatalities identified as alcohol-related in Tasmania in the 3 years, 1979 to 1981, when compared by quarter as in Table 7 show the significant increase in the involvement of alcohol in accidents in the December quarter. Table 6: Alcohol Sales, Tasmania 1978 to 1981 Year and Quarter Sales ($ x 1,000,000) 1978 March 23.0 June 23.2 September 22.7 December March 26.0 June 25.1 September 25.6 December March 26.5 June 26.1 September 26.9 December March 28.9 Table 7: Road Accident Fatalities: Tasmaniai, 1979 to 1981 March June September December All fatalities No. alcohol-involved % alcohol

10 The surveys of self-reported behavior were administered in August 1980, December 1980, March 1981, and June On the basis of Tables 6 and 7, the incidence of drink driving would be expected to have been higher in the second survey, in December 1980, than in the other surveys. Table 4 shows that the respondent's belief that intervention is possible increased in both Hobart and Luanceston following exposure to the campaign, with both increases being statistically significant _( is less than 0.05). However, there was no effect detected on actual intervention behavior (Table 5). If the results are interpreted as indicating that the campaign was effective in Hobart, then the reason for the lack of effect in Launceston is difficult to explain. One hypothesis is that this type of campaign is effective in reducing the sort of drink driving behavior that occurs particularly just before Christmas (when perhaps people who do not normally drive after drinking are likely to do so) but has little effect on drink driving at other times. The 2 Canadian campaigns which gave positive benefits were also of short duration and were run in the pre-christmas period. The effect on intervention would seem to suggest that intervention is widely accepted as desirable, but that practical difficulties mean that it is not attempted often. In addition to the results presented here, the campaign has been shown (Elliott & South, 1983) to have had other positive effects. At the most basic level, a campaign's effects can be measured in terms of its presence, that is, the extent to which people are conscious of the advertising. After the campaign was completed in each city, 96% of the respondents were aware of the television commercials. Croke (1977) indicated that only 75% were aware of the NHTSA campaign using an indirect approach. The unprompted recall of the theme of the campaign was also high at just over 40%. This compares with product advertising where 20% is the norm and a 40% figure regarded as outstanding given such a short period of exposure. (Elliott & South, 1983). While these positive effects are important in that they support the approach used, they are not valid measures of the campaign's effectiveness. THE NATIONAL CAMPAIGN On the basis that the results of the evaluation of the pilot showed that the campaign could be effective in reducing driving after drinking, at least in the pre-christmas period, a national campaign was recommended. 208

11 A national campaign comprising only television advertising using the Paul Cronin commercials was funded for 15 weeks during the period December 12, 1982 to March 26, An indication of the extent of advertising and the associated Target Audience Reach Points (TARP's) is given in Table 8 for the mainland State capital cities. Table 8: Extent of Advertising* by State Capital Cities Capital City State Total Spots* Paid Spots* Bonus Spots* TARP's Sydney NSW ,684 Melbourne VIC Brisbane QLD ,792 Perth WA ,871 Adelaide SA ,907 * All 60-second television commercials. An experimental evaluation of the national campaign was not planned; however, 2 Australia-wide "omnibus" surveys, undertaken on the weekends immediately preceding and following the campaign, were used to gain some information. Two simple questions were asked: 1) How many days, weeks or months is it since you've been to a hotel, club, party of other gathering where someone seemed to have drunk too much to drive a car or other vehicle safely? 2) Did you or someone else try to help that person? Based on the responses to Question 1 (see Table 9), we have identified, again, the relative importance of the time of year when an alcohol related survey is undertaken. Between December and April there is a relative shift of responses from within the immediate month to the period 2-6 months. This is also evident in the results for individual states. 209

12 Table 9: Time Since Attending Function Where Someone Too Drunk to Drive December 1982 April days days days days months months months year year Can't say Never ST1 HJ070 T U O " Sample size A m e a s u r e o f i n t e r v e n t i o n b e h a v i o r is t h e p r o p o r t i o n o f r e s p o n d e n t s w h o h a d b e e n to a f u n c t i o n in the la st y e a r w h e r e s o m e o n e w a s t o o d r u n k to d r i v e a n d t h e y o r s o m e o n e e l s e t r i e d to help. However, i n t e r p r e t a t i o n o f t h e r e s u l t s (Table 10) is d i f f i c u l t g i v e n t h a t o n t h e b a s i s o f the p i l o t c a m p a i g n an i n c r e a s e in i n t e r v e n t i o n w o u l d n o t h a v e b e e n e x p e c t e d (see T a b l e 5). Table 10: Proportion of Respondents Who Identified an Intervention Occasion (Percent) December April Significance State Difference Level NSW VIC NS** QLD WA SA 70.4* 48.2* NS TAS 52.1* 47.8* -4.3 NS Australia Sample size *** * Sample size 50 or less ** NS = not statistically significant *** Respondents who had been to a party in last 12 months 210

13 Comparing probably Table 10 with the extent of advertising identified in Table 8, we note that the significant changes recorded were not a function of extent of advertising, measured in terms of number of spots or TARP's. The pre-campaign values appear to vary significantly; however, they do correlate remarkably well with other drink driving advertising. Both Victoria and Tasmania have utilized material with an intervention theme over lengthy periods whereas in South Australia a highly contentious drink driving campaign was run for a short period straddling the weekend of the pre-campaign survey. With respect to the interpretation of post-campaign results, we point out that those states registering a statistically significant increase in intervention behavior all implemented legislative changes and/or a marked increase in drink driving enforcement. Random breath testing was introduced in New South Wales on December 17, 1982 in association with enforcement and advertising having the theme, "Will you be under.05 or under arrest?" Queensland, on January 1, 1983, lowered the legal blood alcohol level from 0.08 g/100 ml to 0.05 g/100 ml and increased drink driving enforcement, in December Western Australia increased drink driving enforcement via road blocks. In addition, both Victoria and South Australia had random breath testing for some years piror to the campaign. On January 5, 1983, Tasmania introduced random breath testing and lowered the legal blood alcohol level from 0.08 to 0.05 g/100 ml. The effect of all these changes combined with the national campaign has lead to a remarkable consistency in the post-campaign results. Unfortunately, the role which the campaign played cannot be identified. SUMMARY Experimental evaluation of a campaign with the theme "What sort of friend are you? Would you let a friend drive if he's had to much to drink?" has shown that the campaign was effective in reducing driving after drinking, at least in the pre-christmas period. Extension to a national campaign appeared to be associated with an increase in intervention behavior but because of other road safety activities which occurred at the same time the significance of the campaign cannot be quantified. 211

14 ACKNOWLEDGEMENTS The authors would like to express their appreciation to their respective organizations for permission to publish the paper. However, the views expressed in the paper are those of the authors and do not necessarily represent those of the Federal Office of Road Safety or the Victorian Road Traffic Authority. REFERENCES Croke, J. A. (1977). ASAP P.I. & E: Countermeasures: Summary of activities and effectiveness. Washington, D.C.: U.S. Department of Transportation. Elliott, B. J., and South, D.R. (1983). The Development and Assessment of a Drink Driving Campaign: A Case Study. Canberra: Office of Road Safety. Farmer, J. J. (1975). The Edmonton Study: A pilot project to demonstrate the effectiveness of a public information campaign on the subject of drinking and driving. In Israelstam, S., and Lambert, S. (eds.), Alcohol, Drugs, and Traffic Safety. Toronto: Addiction Research Foundation. Miles, D. D., and Clay, T. R. (1977). An analysis of Public Information and Education Activity: City of Phoenix. Washington, D.C.: U.S. Department of Transportation. Miller, E.G. (1976). An analysis of the Post Advertising Telephone Survey 1975, Los Angeles. Washington, D.C.: U.S. Department of Transportation. Pierce, J., Hieatt, D., Goodstadt, L., Lonero, A., Cunliffe, A., and Pang, H. (1975). Experimental evaluation of a community based campaign against drinking and driving. In Israelstam, S., and Lambert, S. (eds.). Alcohol, Drugs, and Traffic Safety. Toronto: Addiction Research Foundation. 212