A New Measure of Alcohol Density

Introduction: Alcohol density is normally measured as the number of retail establishments selling alcohol. However, the quantity of alcohol available should be measured in both a locational context (number of establishments) and by concentration (amount of alcohol within each retail establishment). Food metrics, for example, assess both the number and type of outlet (supermarkets versus fast food). This implies that a simple numbers measure is intrinsically flawed and incomplete.

Methods: This study measures alcohol concentrations (AC) within 4 distinct types of retail outlets – Supermarkets, Liquor, Convenience, and Drug stores. We construct an alcohol concentration index by dividing the linear feet of shelf space within each type of establishment by the total square footage with additional subdivisions by the type of alcohol beverage – beer, wine, and spirits. Data was collected by graduate students and faculty from Touro University in the summer of 2007 for a total of 100 retail establishments in 4 California cities – Vallejo, Modesto, San Francisco, and Danville including the socio-economic characteristics of each city. Analysis was multiple regressions using SPSS.

Results: Surprisingly, cities with higher income have higher ACs than poorer cities. Beer has the AC, but not the highest per ethanol ounce. Liquor stores have the AC but some drug stores had substantially higher indexes.

Conclusion: When public policies are implemented for restricting the quantity of alcohol in order to limit the damage from alcohol abuse, the concentration of alcohol within each outlet should be an important part of the regulatory debate.