Presented at the 30th Annual Alcohol Epidemiology Symposium of the Kettil Bruun Society for Social and Epidemiological Research on Alcohol in Helsinki, Finland, 31 May – 4 June, 2004

Tsunami or ripple? Studying the effects of current Nordic alcohol policy changesRobin Room

Centre for Social Research on Alcohol and Drugs (SoRAD)Stockholm University

AbstractUnder pressure from the single-market rules of the European Union, Nordic countries have embarked on one of the biggest changes in policy on alcohol availability in 50 years. The changes include a 45% reduction in Denmark and a 44% reduction in Finland in spirits taxes, along with reductions in taxes for other alcoholic beverages in Finland, and substantial increases in cross-border traveler’s allowances borders within the EU, which encourages cross-border purchases in low-tax countries such as Germany, Estonia and now Denmark. These changes are expected to have effects not only in Denmark and Finland, but also in southern Sweden, given its easy access to Denmark. On the other hand, northern Sweden is expected to be little affected, and thus can serve as a control site for studying the results of the changes. The paper described the design and research questions of a collaborative Nordic study to measure the short- and medium-term effects of the changes, both on drinking amounts and patterns and on alcohol-related problems. The design includes annual reinterviews of panels of respondents to examine the question: Whose drinking is affected by such changes, and by how much and under what circumstances? In particular, how is the behaviour of heavier drinkers affected? Hypotheses from three theories of patterns of change in drinking will also be tested: (1) Norström’s application of the gravity model of decrease in effects with the square of the increase in distance from the border; (2) Skog’s theory of the collectivity of drinking cultures; and (3) some predictions from the Becker theory of rational addiction.

Key words: alcohol availability, traveler’s allowance, alcohol taxes, gravity model, rational addiction, collectivity of drinking

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Tsunami or ripple? Studying the effects of current Nordic alcohol policy changes1

Robin RoomCentre for Social Research on Alcohol and Drugs (SoRAD)

Stockholm University

General backgroundIt is well recognized that the availability of alcohol substantially affects levels and

patterns of drinking, and rates of alcohol-related problems (Edwards et al., 1994; Babor et al., 2003). A major dimension of alcohol availability is its price, which can be substantially affected by the level of taxation (Österberg, 2001), and a substantial economic literature considers the effects of taxes on alcohol consumption and problem levels (Cook & Moore, 1999; Chaloupka et al., 2002). High taxes, particularly on distilled spirits, have been a major element of alcohol policy in all Nordic countries since the first decades of the 20th century. All except Denmark have also substantially restricted alcohol availability in other ways, for instance by requiring bottles or cans of alcoholic beverages to be purchased in a limited number of government-owned stores.

The general effects of alcohol taxation and prices on alcohol consumption and problems have been widely studied at the population level, with a number of such studies carried out in the last half-century in the Nordic countries (see Mäkelä et al., 2002; Holder, 2000). Whether in the Nordic countries or elsewhere, there has been much less study of the differential effects on different segments of the population. Little direct information is available on whose drinking changes by how much and in what circumstances when there is a change in alcohol taxes or availability. The study described in this paper is designed to study precisely these questions, with individual-level data. In this, the study will complement the aggregate-level time-series and other analyses of the same historical experience which can also be expected to be conducted in the next few years.

Studying the effects of a general policy change on consumption in different segments of the population also offers a chance for direct testing of major theories of change in drinking, as described below, including the theory of the collectivity of drinking cultures (Skog, 1985). This theory is an important component of what is variously called the “new public health approach” or the “distribution of consumption” model of the relation between alcohol policies, alcohol consumption levels and patterns, and drinking-related problems (Room, 2002a).

The changes to be studiedIn recent months, substantial changes have occurred in Nordic alcohol policies, both in

terms of levels of taxation and in terms of the amounts of alcohol which travelers can legally bring across national borders (see Table 1).

This paper describes a coordinated study which aims to study the effects of these changes. The primary changes to be studied are: (1) the effects in Denmark and southern Sweden of a large reduction in Danish spirits taxes, and in Finland of a large reduction in alcohol taxes, (2) the effects of substantial increases in traveler’s allowances for alcohol imports in southern Sweden (primarily imports from Germany and Denmark) and in Finland (primarily imports from Estonia).1 Prepared for presentation at the 30th Annual Alcohol Epidemiology Symposium of the Kettil Bruun Society for Social and Epidemiological Research on Alcohol in Helsinki, Finland, 31 May – 4 June, 2004. Håkan Leifman serves as study director of the Swedish arm of the project, Kim Bloomfield for the Danish arm, and Pia Mäkelä for the Finnish arm. Involved in the project as consultants or collaborators are: Philip Cook, Gerhard Gmel, Heli Mustonen, Esa Österberg, Jürgen Rehm and Ole-Jørgen Skog. This paper draws on and reflects the collaborative work of these colleagues on different aspects of the project.

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Table 1. Major tax and availability changes studiedDate of implementation

Nature and place of change

Mainly affects:

Oct. 1, 2003 Danish spirits tax reduction

Denmark, southern Sweden

Jan. 1, 2004 Finnish, Swedish, Danish increase in traveler’s allowances

Denmark, Finland, southern Sweden

May 1, 2004 Finnish change in traveler’s allowance from Estonia

Finland

March 1, 2004 Finnish tax reduction Finland

The effects of these changes in different segments of the population will be studied in Denmark, Finland and southern Sweden with panel (longitudinal) as well as repeated cross-sectional population surveys, using northern Sweden as a control site.

The Danish spirits tax decrease and cross-border shopping. Danish taxes on spirits were lowered on October 1, 2003 by 45%, to 43.75 DKK per bottle (70 cl. of 40% ethanol). (http://www.skm.dk/slutfil.php3?SlutFilId=2911) The price of cheaper brands of spirits in Denmark dropped by about 25%. Danish spirits taxes are already considerably lower than in other Nordic countries, and the reduction further increased the discrepancy.

With the Öresund bridge linking Copenhagen with Malmö, Sweden’s third-largest city, there had already been substantial cross-border importing of alcohol, particularly in southern Sweden. Only 30% of the alcohol consumed in the Skåne (southernmost) region of Sweden was purchased from the Swedish government alcohol stores, with much of the remainder accounted for by spirits purchased in Germany and Denmark (Leifman & Gustafsson, 2003, Table 5.5). A discussion has started in Sweden of whether and when Sweden will feel compelled to lower its spirits taxes, also. The Swedish Prime Minister has stated that the government will wait until it sees what happens after the Danish change before deciding on any decrease of its own. In January 2004 a member of Parliament was named to lead an investigation of the alcohol situation in southern Sweden lasting at least 6 months and to recommend policy responses. Håkan Leifman, on leave from his position at SoRAD, is serving as the secretary of this investigation. In this circumstance, it is unlikely that any Swedish alcohol tax change would take effect before the beginning of 2005.

While spirits taxes are lower in Denmark than in other Nordic countries, they are higher than elsewhere in the European Union (Karlsson & Österberg, 2001), and higher particularly than in Denmark’s only land neighbor, Germany. The Nordic countries in general, along with Britain and Ireland, have been under pressure from the rest of the European Union to harmonize their alcohol taxes downward. Formal negotiations over harmonization have largely failed to bring tax rates closer, due in part to resistance to imposing any taxes on wine in 6 EU countries. The most recent discussion of the harmonization of alcohol taxes, on 18 September, 2002, again failed to reach resolution of the issue (http://europa.eu.int/comm/secretariat_general/meeting/doc/pvcomm_20020911_1580_fin_en.pdf). In the absence of harmonization by intergovernmental agreement, the European Commission has relied on mechanisms such as large cross-border traveler’s allowances to create pressure to bring tax levels down in the high-tax jurisdictions (Nordlund & Österberg, 2000). The Danish reduction in

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spirits taxes, to a level much closer to the German tax level, and the Finnish reduction ahead of Estonia’s accession to the EU, may be seen as in part successes for this implicit policy.

There is no doubt that, for consumers living near the border, cross-border shopping becomes popular when there are substantial differences in alcohol taxes and a relatively open border. This has been documented for the Danish-German border (e.g., Bygvrå, 1990), and has become a substantial factor, as mentioned, in the part of Sweden nearest to Denmark. An analysis of Swedish data by Norström (2000b), however, suggests that willingness to travel to purchase alcohol started falling off at about 100 km. from the border, and disappeared entirely at between 250 and 300 km. (See the discussion of “The gravity model of distance effects” below.)

The Finnish tax decreases on spirits and other alcoholic beverages. Estonia enters the European Union in May, 2004, at which point within-EU traveler’s allowances on import of spirits come into effect for travelers to Finland. Taxes on alcoholic beverages, including spirits, are low in Estonia, and the trip by fast ferry between Helsinki and Tallinn takes only about an hour.

In this circumstance, the Finnish government decided to reduce the tax on spirits by 44%, on fortified wine by 40%, on table wine by 10%, and on beer by 32%, effective 1 March, 2004. (Helsingin Sanomat, international edition, 21 Aug. 2003)

Increases in traveler’s allowances. On 1 January, 2004, the traveler’s allowances for those entering Denmark, Finland and Sweden from other EU countries increased to the general EU levels, and in May 2004 these levels will come into effect, also, between Estonia and Finland. Table 2 shows the relevant allowances for tax-free imports for Denmark, Sweden and Finland prior to the changes, and the general EU “guidance” on

Table 2. Traveler’s allowances for alcohol imports, in liters of each beverage

Within-EU to Denmark<1/2004

Within-EU to Sweden <1/2004

Within-EU to Finland<1/2004

Estonia to Finland <5/2004

General within-EU “guidance”: imports for own use

Spirits & 1.5* 5 1 1* 10Fortified wine &

20* 6 3 2* 20

Table wine & 90 52 5 2 90Beer no limit 64 64 16 110

*either spirits or fortified wine. Source: http://europa.eu.int/abc/travel/shop/index_en.htm

imports that are assumed to be for the traveler’s own use and thus not subject to duty on entry. Except as noted, the amounts are cumulative, not alternatives to each other. These general EU guidelines came into effect for the three countries at the beginning of 2004. It should be noted that in April, 2004 the EU Commission has proposed an amendment to the directive on General arrangements for products subject to excise duty, which would end any “guidelines” on traveler’s allowances altogether and require cross-border sales of alcoholic beverages and through carriers be allowed (http://europa.eu.int/comm/taxation_customs/taxation/rep_dir12_en.pdf). The British and Swedish finance ministers have announced their opposition to this amendment.

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Previous experience of the effects of changes in taxes and traveler’s allowancesStudies of the aggregate effects of tax changes. The relatively high spirits-tax regime in

Denmark has been in effect since 1917, when, in wartime conditions of food shortages, the spirits taxes were raised to over 12 times their former value. The results were large decreases in per-capita alcohol consumption and in acute and chronic health consequences of drinking, and an overnight change from Denmark being a mainly spirits-drinking to being a mainly beer-drinking culture (Bruun et al., 1975:73). With differential tax rates and availability disfavoring spirits in all the Nordic countries, the other Nordic countries have gradually also turned from “spirits-drinking” to “beer-drinking” societies, although the predominance of beer has come to them much later than to Denmark (Leifman, 2001b).

As the Danish experience in 1917 vividly demonstrated, tax rates affect the level of alcohol consumption and the rates of alcohol-related problems in a population. High taxes on alcoholic beverages are viewed in the alcohol policy literature as one of the most effective measures to hold down levels of alcohol consumption and drinking problems (e.g., Edwards et al., 1994). These conclusions are in considerable part based on studies of the effects on the level of alcohol consumption of alcohol taxes or prices, which are common in the literature, including in the Nordic countries (Österberg, 1995).

There have been a number of studies of price elasticity in Nordic countries (Österberg, 1995). For Sweden, the price elasticity estimates commonly given are –1.3 for beer, -0.9 for wine and -0.9 for spirits (Assarsson, 1991), while for Finland they are –0.6, -1.3 and –1.0, respectively (Salo, 1990; Österberg, 1995). The estimates by Leppänen et al. (2001) of price elasticity for alcoholic beverages as a whole in EU countries find slightly less elasticity in Denmark (-0.57) and Finland (-0.68) than in Sweden (-0.86). These price elasticity estimates for Nordic countries do not differ greatly, for instance, from estimates of elasticities in the United States, although the Nordic demand for beer seems to be somewhat more price elastic than the U.S. demand. (For the U.S., the approximate values usually given are -0.3 for beer, -1.0 for wine and –1.5 for spirits (Chaloupka et al., 2002), values that derive originally from estimates by Ornstein and Levy (1983).)

Drawing on the literature on price elasticity, an international working group in 1995 estimated the effects on consumption in Sweden, Norway and Finland if prices there fell to the existing Danish level and to the existing German level (Holder et al., 1995). Their estimates were that the Finnish consumption would rise by 23% and 46%, respectively. The forthcoming changes in Finland will offer a direct test of the predictive model used in those estimates.

Studies of differential effects of tax changes on different population subgroups. Most studies of price elasticity are based on analyses at aggregate, population levels. They therefore contribute no direct evidence on whose drinking changes or by how much when taxes and prices change, a question which holds important implications for alcohol policy. One possibility would be that the change is concentrated among lighter drinkers. Arguments along this line are commonly backed up by the idea that addicted drinkers would not be influenced by such contextual influences as the price of a drink. A 1995 study (Manning et al., 1995) found evidence that heavy drinkers were less influenced by price than moderate drinkers. This study has been influential in the literature, although it is based on an analysis of cross-sectional data, rather than directly measuring the effects of change. A more recent cross-sectional study in which Manning was also involved (Farrell et al., 2003) found evidence in the opposite direction, concluding that there was substantial price elasticity for heavy drinkers with symptoms of alcohol abuse or dependence. This conclusion is in accord with other findings in the literature, such as the conclusion of Laixuthai and Chaloupka (1993) that beer tax rates had a greater effect among American youth on frequent or heavy drinking than on less frequent or lighter drinking.

Reviewing the current econometric literature on the effects of price on alcohol consumption and problems, Chaloupka et al. (2002) note critically that the literature is “not based

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on natural experiments. For example, no data are available comparing the amounts of alcohol consumed by individuals or groups at different prices, with all other variables held constant. Instead, researchers use cross-sectional data … or time series of such cross-sectional analyses”. The present study is an answer to this criticism.

Indirect evidence on the effects of price or tax changes on different groups of drinkers can be gained from studies of the effects of the changes on alcohol-related problems. If alcohol tax increases affect rates of cirrhosis deaths, of drinking-driving casualties, or of violent crimes, this is not only an important policy finding in its own right, but also implies that the drinking patterns of those prone to these outcomes are affected. Such effects have been found in U.S. studies (Cook, 1981; Cook & Moore, 1993).

The most direct way to measure whose drinking changes and by how much when there is a change in policy is with cohort or follow-up data from individual drinkers, interviewed before and after a significant policy change. A quasi-experimental design with interviews also in a control population increases confidence that the changes in drinking and alcohol-related problems are due to the change in policy.

There have been relatively few such studies of the effects of changes in alcohol taxes, and none that has included a control population. Citing three literature reviews, Kuo et al. (2003) remark that “the critical lack of recent research on price effects at the individual level has been widely observed”. Kendell et al. (1983) used longitudinal data to study the effects of a rise in alcohol taxes in Scotland, finding that heavy drinkers reduced their drinking at least as much as light drinkers. However, with the exclusion of abstainers from the follow-up, the study’s design was not optimal.

A study of the effects of a substantial reduction in the tax on foreign spirits in Switzerland has been carried out by Gerhard Gmel, Jürgen Rehm and colleagues (Kuo et al., 2003). Hypotheses to be tested in the study included: that the proportion of spirits in total consumption would increase after the tax change; that heavy drinkers would be more responsive than others to the change; that alcohol-related harm indicators would increase; that the effect of the change would be greater on respondents living nearer the border, and lesser on those in regions with more socially integrated drinking of spirits; and that the change would result in an increase in alcohol consumption in risky situations. An initial sample of 4007 completed interviews interviewed in spring 1999 was followed up, with 2923 (73%) reinterviewed 2½ years later in autumn 2001. Between these two main datapoints, two follow-ups of a subsample of the original sample were also conducted in autumn 1999 and spring 2000. Three reports on the study have been published or are in press (Kuo et al., 2003; in press; Heeb et al., 2003), and analysis and publication on the study continues.

Foreign spirits, which accounted for 53% of the Swiss spirits market before the change, dropped in price by 30-50%, while prices of domestic spirits stayed much the same. An analysis comparing the “before” data with follow-up data at 28 months (Kuo et al., 2003) found an increased consumption of spirits in all subgroups studied: in men and women, in different age groups, and at different levels of consumption. The study found that the increase in consumption was relatively higher in moderate than in heavier drinkers, though regression to the mean effects may not have been sufficiently controlled for.

In the Swiss study, younger age groups were generally more affected by price than older age groups, although one analysis found this to be specific to young males (Heeb et al., 2003). The general results in the econometric literature suggest a higher elasticity among youthful than among older drinkers (Kenkel, 1993; Chaloupka et al, 2002).

Studies of the effects of price and availability differentials on cross-border alcohol sales and consumption. It has long been recognized that where alcohol is more available or cheaper across an easily-crossed border, a substantial cross-border trade tends to build up. This has been studied in terms of cross-border purchasing between U.S. states (Beard et al., 1997), as well as

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across international borders in North America (Macdonald et al., 1999; Lange et al., 2002) and in northern Europe (Milhoj, 1993; Lund et al., 2000; Norström, 2000b; Trolldal, 2000). Typically, studies find that while cross-border purchases often account for only a few percent of all alcohol consumption in a whole country or state, the effects can be quite substantial in areas close to the border. Among the very few studies of what happens when border differentials change, Milhoj (1993) found that tax reductions on wine in Denmark in 1991 and 1992 reduced the proportion of wine consumed in Denmark which had been bought abroad (primarily in Germany) from 26% to 14%. Studies on the U.S.-Mexican border have found that decreased availability on the side of the border with higher availability (Mexico) does reduce the border drinking traffic (Baker et al, 2000; Voas et al., 2002).

Studies of the differential effects of availability changes on consumption and problems. Studies of the differential effects of other dimensions of alcohol availability besides taxation have been somewhat more common. In particular, a number of longitudinal studies with individual-level data have been carried out in Nordic countries. The 50-year tradition of Nordic studies of the effects of alcohol controls was recently reviewed in a project including many participants in the present proposal (Room, 2002b; Mäkelä et al, 2002), with special attention to what the studies found on differential effects in different population groups. The project included several reanalyses of longitudinal data from the big Finnish liberalization of availability in 1969, after which alcohol consumption rose by about one-half from one year to the next (Mäkelä, 2002a; 2002b; Mustonen & Sund, 2002). The general finding has been that policy changes often have differential effects by population segment and pattern of drinking, and for different types of alcohol problems, with effects often concentrated particularly among heavier drinkers (Room et al., 2002). Again, some studies show a differential effect of changes in availability, with a stronger effect in younger age groups (e.g., Mäkelä, 2002b; Ramstedt, 2002).

Theoretical models which can be tested by data on the effects of the changesThe gravity model of distance effects. The idea that retail trade diminishes in proportion

to the square of the geographic distance away was put forward as a summary of U.S. experience already in 1931 (Reilly, 1931). This “gravity model”, as it became known, was subsequently applied to a variety of phenomena including migration (e.g., Stewart, 1941; Ziph, 1949). Norström (2000b) has applied the model in rough form in examining the effects of an earlier increase in the traveler’s allowance between Denmark and Sweden, the 1995 change from 1 to 5 liters of table wine and from 2 to 15 liters of strong beer (Trolldal, 2000). Using aggregate data from 9 areas in southern Sweden, and taking as the distance from the border the kilometers from the largest town in the area to Helsingborg, the quickest crossing-point to Denmark prior to the Öresund bridge, Norström showed the effects of the 1995 change on the monthly sales in Swedish government liquor stores varied as the square of the distance from the Danish crossing. He also found that the effects of the change was greater two years afterward than one year afterward: for the closest areas, from about 17% to about 27%; for the most distant, from 0% to about 5%. Norström’s study was of the disappearance of sales in Sweden at the aggregate level, and does not speak to what happened to consumption at the individual level. The changes he found were presumably the net result of substitution of Danish purchases for Swedish purchases, and would not capture any increase in consumption as a result of the cheaper prices. Nor, of course, do his findings tell us anything about variations between different population groups and classes of drinkers in the effects of the change. In the present study, it is proposed to test the hypothesis that the gravity model of distance effects applies to changes in alcohol consumption Sweden, Finland, and Denmark, with the effects of the changes in traveler’s allowances diminishing in proportion to the square of the respondent’s distance from the nearest point of access – the German border in Denmark, Helsinki (as the ferry port for Estonia) in Finland, and the Danish

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bridge and ferry ports in Sweden. It should be noted that the general strength of the effect in Denmark and Finland is expected to be muted by the domestic tax changes occurring in the same year.

The collectivity of drinking cultures. Collecting longitudinal data on drinking in the general population under changing circumstances also allows a contribution to testing a major theoretical proposition in the field: the proposition that, when consumption levels change in the population, the members of a culture tend to change their drinking proportionately, in concert with one another (Skog, 1985). The recent review by Gmel and Rehm (2000) has pointed to the need for further empirical testing of this proposition. Although they note that “‘moving in concert up and down the consumption scale’ is about change”, so that “empirical testing requires at least two time-points”, Gmel and Rehm found only three studies which “used follow-up methodology to test whether subgroups were moving in concert”. The results from these studies were inconclusive, although the reviewers noted the need for future studies “to test empirically for regression dilution bias” (i.e., regression to the mean), as a possible explanation of the pattern of results. In a further exchange, Skog (2001) asserted that “the theory of collectivity makes predictions about marginal distributions, but not about the bivariate distributions of repeated measurements”, while Gmel and Rehm (2003) used simulations to show that very similar results could be obtained at the level of marginal distributions from very different distributions of change between heavier and lighter drinkers. While agreeing with Skog (2001) that longitudinal social network data would be optimal for “an empirical testing of the social mechanism underlying collectivity at the level of individual drinkers”, we contend that follow-up data on changes in individual behavior, under substantially changing circumstances for the population as a whole (e.g., a change in alcohol taxes), offers a substantial step forward in testing and refining a theory of the collectivity of drinking cultures.

Rational addiction. Becker and Murphy (1988) have put forward a “theory of rational addiction” which has received much discussion (e.g., Skog, 1999), but somewhat less empirical testing. Becker and Murphy’s theory takes as one of its postulates that “a person’s consumption decisions will respond to changes in the expected future costs of consumption, such as an anticipated increase in price” (Chaloupka et al., 2002). As Chaloupka and associates go on to note, “although this assumption may appear to be counterintuitive, it generates a prediction that can be tested using data on alcohol consumption by the same person in 3 or more years”. Knowledge beforehand that there will be a drop in price (which has been measured in the Swedish and Danish data with an item on whether the price of spirits next year will have increased, decreased, or stayed the same), if it produces an anticipatory rise in consumption, should therefore produce less change in drinking one year later. The changes in effective price from the tax reductions and increases in traveler’s allowances to be studied in the present project, together with the project’s longitudinal design, offer an unusual opportunity to test this and other predictions of the Becker and Murphy theory, previously tested primarily on youth samples (Grossman et al., 1998), in a general adult population.

Research traditions and materials drawn on in the study

Monitoring unrecorded consumption: The Swedish Alcohol Monitoring Survey. Nordic countries have excellent and longstanding traditions of collecting economic, social and health statistics. These include detailed information and tabulations on alcoholic beverage sales through regular channels. However, as elsewhere, alcoholic beverages are also made, distributed or imported in both legal and illegal ways outside the regular channels. Since the size of this unrecorded and informal trade and consumption has often been an issue in policy discussions (Nordlund & Österberg, 2000), considerable energy has been devoted in the Nordic countries to estimating and monitoring trends in the various types of unrecorded alcohol consumption

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(Österberg, 2000; Kühlhorn et al., 1999; see Leifman, 2001a). Since July, 2000, a monthly survey of 1500 adult inhabitants of Sweden has been funded by the Ministry of Social Affairs and Health and conducted under the direction of Håkan Leifman of SoRAD, to estimate the size of traveler’s imports and other categories of unrecorded alcohol consumption in Sweden (Leifman & Gustafsson, 2003). This survey, along with the previous Swedish work (Kühlhorn et al., 1999), thus represents a well-established tradition and survey technology of measurement of traveler’s imports and other unrecorded aspects of alcohol consumption. It also provides a base for added questions in connection with other studies, including the present study.

Analyzing individual longitudinal data on the effects of policy change: dealing with regression to the mean. An important question for alcohol policy, as mentioned above, is whose drinking is affected how much by a policy change; in particular, are heavy or risky drinkers affected by the change and, if so, are they affected more or less than lighter drinkers? It would be a powerful policy argument against an alcohol policy which applies to all drinkers -- whether or not they are heavy or risky drinkers – if only the lighter drinkers were to be affected by it.

Analysis of such a question with individual-level longitudinal data must deal with the issue of regression to the mean. Such regression arises from two sources: from measurement error, and from unsystematic fluctuations in individual behavior over time. As an example of the latter, the drinking patterns of many heavy drinkers in the general population vary considerably over time, with periods of heavier drinking interspersed with periods of much less drinking (e.g., Kerr et al., 2002). The result of the fluctuations from both sources is that there is a high likelihood that, without any policy change or external intervention, a substantial proportion of those measured as heavy drinkers in a first interview will be measured as drinking less in a second interview. The challenge for an analysis of the effects of a policy intervention is to control out the effects of such regression to the mean arising from unsystematic fluctuations.

One simple method of doing this is to compare changes in similarly-defined population subgroups between a control population and the intervention population. This method has been

used by Pia Mäkelä in her longitudinal reanalyses of the effects of the 1969 Finnish change in availability. While the original data collection lacked a formal control group, Mäkelä (2002a; 2002b) was able to identify longitudinal samples in Norway and the U.S. with the same period between interviews (one year), but without any policy change occurring during the period. While Finnish Time-1 frequent drinkers showed less increase in frequency of drinking than Finnish Time-1 infrequent drinkers, the difference in frequency at Time 2 between Finns and Norwegians or Americans who drank at equal frequency at Time 1 was much greater for Time-1 frequent drinkers than for Time-1 infrequent drinkers. Controlling in this straightforward way for regression to the mean, Mäkelä concluded that “changes in drinking frequency and volume of drinking were most often greatest in those groups which initially had the highest level of consumption, i.e., that the changes in a group were often approximately proportionate to the level of consumption in the group” (Mäkelä, 2002b).

In as yet unpublished work, Skog has pointed out that this method is problematic if the mean values at Time 1 or the regression coefficients differ in the control sample and the intervention sample, and has proposed an alternative method involving statistical comparison of regression curves. It is intended that this method will be developed and used in the course of the present project.

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An advance in the present project, also, is the use of a control population, in which the same data will be collected at the same time.

The “before” data samples. The present study can only be carried out because nationally-financed data have been collected in each of Denmark, Sweden and Finland in the period July – December 2003, serving as the “before” data in the present study.

i. Sweden. As noted above, a monthly Monitoring Survey of a representative sample of 1500 persons aged 16-80, financed by the Ministry for Social Affairs and Health, is directed by Håkan Leifman and carried out for SoRAD by TEMO, an established Swedish population survey firm (Leifman & Gustafsson, 2003). Each month’s sample is independent, and is generated by random digit dialing (RDD), with interviewing conducted by a Computer-Assisted Telephone Interviewing (CATI) system. The response rate for the survey, conservatively estimated, is about 60%. The questions for the purchasing monitoring survey take between 5 and 10 minutes, allowing additional questions to be added without compromising the response rate or other aspects of the study.

Interviews in the 3 months July – September 2003 will be used for the “before” sample for the study of the combined effect in southern Sweden of the change in Danish spirits taxes and traveler’s allowances. Interviews in the 3 months October – December 2003 will be used for the “before” study of the effects in southern Sweden of the changes in the traveler’s allowances for those returning to Sweden. Comparison of the results on changes between 3rd quarters and changes between 4th quarters will yield an estimate of the effects of the spirits tax changes. Interviews in northern Sweden from the two 3-month periods will be used for the control sample from a district minimally affected by the changes.

For purposes of the study, Sweden has been divided into three regions (see map), with the “southern region” comprising the areas nearest to Denmark: the counties of Skåne, Blekinge and Halland, and the city of Gothenburg. These areas are all close to Denmark, with a bridge to Copenhagen a little northwest of Sweden’s southernmost point, and ferries to Denmark elsewhere. The “northern region” will consist of northern parts of Sweden: the counties of Norbotten, Västerbotten, Jämtland, Västernorrland, Gävleborg, Dalarna, Örebro and Varmland. Five districts 100 km. or less from the Finnish border at the extreme north of Sweden (Haparanda, Kalix, Pajala, Övertorneå and Överkalix) are also excluded, in view of the tax changes in Finland. This “northern region” does not include the Stockholm metropolitan area (the bulge on the east coast); Stockholm is somewhat more likely to be affected by changes in traveler’s allowances, because of ferry and air traffic to the area.

About 1000 interviews were to be completed in each of these designated northern and southern regions in each 3-month period. This sample was supplemented with 500 extra cases, selected and interviewed probabilistically, in each of the two regions in each of the two 3-month periods. In total, 1527 persons were interviewed in the 3rd quarter in the southern region, and 1541 in the 4th quarter. Corresponding figures for the northern region are 1553 and 1545.

ii. Denmark. A sample of 2030 residents of Denmark aged 16-80 has been interviewed using random digit dialing (RDD) and computer-assisted telephone interviewing (CATI) in the 3rd

quarter of 2003, with financing from the Danish Forskningsråd (Research Council). The study is directed by Kim Bloomfield of the University of Southern Denmark, with the fieldwork performed in July-September 2003 by Vilstrup, an established Danish survey research fieldwork agency. Using a conservative estimation procedure, the response rate is 40% (an unfortunately low rate which is in line with other current Danish experience). In addition to functioning as the Danish “before” sample for the present project, the sample constitutes the Danish participation in the Gender, Alcohol and Culture International Study (GENACIS).

iii. Finland. A postal survey of persons aged 16-69 has been conducted by the Finnish Statistical Bureau in September and October 2003. The study is directed by Pia Mäkelä of the Alcohol and Drug Research Group (ADRG) of the National Research and Development Centre

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for Welfare and Health (STAKES), Helsinki. A sample of 4000 persons was drawn from the population register, resulting in about 2400 completed questionnaires (60% response rate). This method of interviewing is well established in Finland. The survey is the latest in a series of Finnish national surveys on drinking patterns and problems and related issues conducted since 1968, approximately every four years since 1976 (see, for example, Mustonen et al., 1999).

At a meeting of the study team on 19 and 20 May, 2003, agreement was reached on a common set of items to be used in the “before” studies for the sake of the present project (see Table 4), as a part of wider agreements on the design of and analysis plans for the study.

Research design. The full design of the study is for four waves of data collection in the population aged 16 and above in Denmark, in Finland, and in two regions of Sweden (see the chart, “Overview of Fieldwork”). The first wave of data has been collected in Denmark prior to the Danish tax change; in Sweden (1) before the Danish tax change and also (2) after it but before the change in traveler’s allowance; and in Finland before the changes in traveler’s allowances and in taxes.

The double data collection (3rd quarter and 4th quarter of each year) in Sweden reflects that two separate policy changes are expected to affect Swedish alcohol purchasing and consumption during the study period. One is the change in Danish taxes on October 1, 2003, and the other is the increase in traveler’s allowances on January 1, 2004. Comparison of the 4 th-quarter samples will test for the effects in south Sweden of the increase in traveler’s allowance, with the Danish tax decrease already in effect, while comparison of the 3rd quarter samples will test for the effects of the tax change and the increase in traveler’s allowances together. The difference in effects is then attributable to the tax decrease.

The second wave in each country, consisting in part of a follow-up of cases from the first wave and in part of a new sample, will be interviewed at the same season one year later. The third and the fourth waves, similarly, will be composed in part of a follow-up of cases from the first wave and in part of a new sample, and will be interviewed at the same season two years and three years later than the first wave.

The one-year period between waves of reinterviews and new samples was chosen because alcohol consumption in Nordic countries is heavily seasonal (for Sweden, see Leifman & Gustafsson, 2003), and there is considerable variation, also, in foreign travel patterns by season. A one-year period between the sampling points controls out this seasonal variation.

The full design of the study provides for three annual waves of interviewing after the changes in order to measure medium-term as well as short-term effects. Studies of the effects of alcohol policy changes have usually found an immediate effect. In the case of the effects of alcohol taxes, this would correspond to a negative short-run price elasticity. The effect over a longer term – the long-run price elasticity -- may be different, and in fact has often been found empirically to be different (e.g., Grossman et al., 1998; Johnson et al., 1992). The effects of social policy interventions often decay over time (e.g., Ross, 1984), and some econometric studies accordingly find greater short-run than long-run price elasticities for alcohol (e.g., Johnson et al., 1992). But the study of the effects of the Swiss spirits tax decrease found an effect persisting after 2½ years, and some econometric studies have found greater long-run than short-run elasticities (e.g., Grossman et al., 1998), interpreted by the authors in terms of economic theories of rational addiction (see Skog, 1999). Similarly, Norström (2000b) found a consistently greater effect of a change in availability on cross-border shopping after 2 years than after 1 year. Collecting cohort and repeated cross-section data for each of three years after the changes will allow an analysis that examines the decay, persistence or strengthening of effects over time, at least in the medium term.

In each of the 3 reinterview waves, efforts will be made to reinterview all those interviewed in the “before” wave, whether or not they were previously reinterviewed. Rates of reinterview of those designated for reinterview from the 2003 samples are estimated at 70% for 2004, 60% for 2005, and 50% for 2006. On the basis of the estimates, in the 2004 wave, there

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will be 1400 reinterviews in Denmark and 1680 in Finland, and 1050 reinterviews in each of the four Swedish samples. The corresponding numbers for the 2005 wave will be 1200, 1440 and 900, and for the 2006 wave 1000, 1200 and 750.

In addition to these panel data, data will be collected from new samples of the population aged 16-80 at the time of the 2004, 2005 and 2006 waves, by RDD telephone interviews in Denmark and Sweden, and by postal survey in Finland, using the same fieldwork agencies. The sample size will be 1000 completed cases in each of Finland and Denmark. In Sweden, the

additional questions for the study will be asked of the ongoing Monitoring Project samples, with 1000 cases available in each of the specially-defined northern and southern regions and in each of the 3rd and 4th quarters of each year. The new independent samples in 2004, 2005 and 2006 allow testing for the effects of sample attrition and for response effects in the cohort samples.

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Together with the reinterviewed cases, they will strengthen the power and population representativeness of

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Table 3. Questionnaire Concordance Sweden Denmark Finland

Alcohol purchases on last trip abroadLast trip out of the country: brought alcohol yourself or together with another,

e.g. a partner?X X §

Can you decide how much you brought in? How many adults brought it in? X X §Which country did you buy drinks in when you bought from a store? X X §Which type of alcoholic drinks did you bring the last time you came home

from another country?X X §

How much strong beer? table wine? strong wine? spirits? X X §How many times travelled out of the country in the last 12 months? X X XDrinking amounts and patternsHow often in the last 12 months: light beer*, strong beer, table wine, strong

wine**, strong cider, spirits?X X X

When you drink [each beverage type], about how much do you drink? X X XHow often in the last 12 months did you drink at least a glass of something

that contains alcohol?X X #

How often in the last 12 months have you drunk at least a bottle of wine [or equivalent] on an occasion?

X X #

How often in the last 12 months have you drunk alcohol: in a restaurant with a meal#; in a bar/pub/disco#; at your own house; at someone else’s house; at a party or other celebration**; with an ordinary meal at home#?

X X X

Problems in connection with drinking in last 12 months: happened more than once; once; no, didn’t happen#

Felt ill, had a headache, or felt physically bad the day after you had been drinking

X X

Quarrel in connection with drinking; fight; caused an accident; rode with someone driving while affected by alc.**; driven while affected by alcohol

X X X

Harmed your work or studies; your family or relationship; injured relations with other family members, including children; harmed your friendships or social life; had a negative effect on your finances

X X

Regretted something you did while drinking X XProblems in connection with drinking in last 12 months: never, <monthly,

monthly, weekly, daily or nearly every dayCouldn’t stop drinking after you began; neglected to do things you should

have because you were drinking; needed a drink in the morning to get going; had guilt feelings or a reproachful conscience because of your drinking; a relative or friend was disturbed about your drinking or suggested you cut down#; a doctor or other health worker…#; impossible to remember what happened the night before because you had been drinking; you or someone was injured because of your drinking¤

X X X

Attitudes about alcohol salesHow old should someone be to buy a bottle of spirits; how old should a youth

be to be offered a spirits drink by his/her parents; do you think that the price of spirits will have increased or decreased in a year; taxes on spirits should be raised, lowered, kept generally the same

X X

Wine should be sold in corner stores X XDemographicsYear of birth; work status; household composition & marital/partner status;

education; geographic location ( urbanization, region); income; gender X X X

How many in household X XX question(s) asked as stated # variant wording in Finland* only significant in Sweden, asked only there ** not asked in Finland§ asked for last 12 months: how often purchased alcohol out of ¤ whether in last 12 months

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country, which countries bought in, how much of each beverage?

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analyses comparing patterns in the population over time (i.e., trend rather than longitudinal analyses).

In addition to the funding from national sources which has supported the “before” studies, support has been received from the Joint Committee of Nordic Research Councils for the Humanities and the Social Sciences (NOS-HS) for data collection in Denmark and Sweden in 2004 and 2005. Further support, to carry out the full design, is being sought from the U.S. National Institute on Alcohol Abuse and Alcoholism.

Content areas and items in the questionnaires. Table 3 shows the items which were asked in the “before” studies in the three countries. The general time period covered is the last 12 months, with questions also when possible about the last 30 days. The intention is that most of the questions will be repeated in the later waves of the study.

ConclusionThe effects of alcohol policies are best studied by studying what happens when the

policies change. Effects in the population at large can often be measured with aggregate statistics. But to study the differential effects of policies in different segments of the population, including segments defined by level and pattern of drinking, individual-level data is needed. Follow-up studies, with the same individuals interviewed before and after the change, are an especially strong test of the differential effects of a policy in different parts of the population. But, within the range of resources normally available for such research, the size of study samples is necessarily limited. This means that it is desirable to focus such studies on policy changes which can be expected to have a relatively strong effect.

The changes in taxation and alcohol availability occurring in late 2003 and 2004 are the most dramatic which have occurred in the Nordic countries in a generation, and are arguably larger than any other sudden changes which have occurred in north America or western Europe in the same period. Their occurrence, then, offers a unique opportunity for a study which can contribute substantial knowledge both at the practical level, in terms of the differential effects of taxes and other availability changes across the population, and at the theoretical level, in terms of testing the gravity model of distance effects and rational addiction theory and testing and developing the theory of the collectivity of drinking cultures.

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