225179 Is off-premise alcohol outlet density really a risk for gonorrhea and crime? Comparing results of analyses with and without propensity score matching

Sunday, November 7, 2010

Katherine Theall, PhD , Global Community Health and Behavioral Sciences, Tulane University School of Public Health, New Orleans, LA
Richard Scribner, MD, MPH , Epidemiology, LSU School of Public Health, New Orleans, LA
William T. Robinson, PhD , Louisiana State University Health Sciences Center, School of Public Health, New Orleans, LA
Background: A number of studies indicate a geographic association between off-premise alcohol outlet density and gonorrhea risk and crime. However the association might be confounded by a tendency of high-risk individuals to reside in neighborhoods with high densities of off-premise alcohol density (e.g., liquor stores), independent of risk (selection bias or endogeneity). Analyses limited to neighborhoods matched on their propensity for high off-premise density (e.g. high poverty neighborhoods) is one method for addressing this type of structural confounding.

Methods: Multilevel ecologic analysis examining a three-year prevalence of age- and sex-adjusted gonorrhea rate across 445 Los Angeles County, California neighborhoods and total violent crime rate across 290 Los Angeles City neighborhoods was conducted using all neighborhoods and only neighborhoods matched based on their off-premise alcohol density propensity score.

Results: Without propensity score matching but with an adjusted model, one unit decrease in the number of off-premise alcohol outlets per mile of roadway was associated with 4 fewer gonorrhea cases per 100,000 (p<0.05) and 16 fewer violent crimes per 1,000 (p < 0.0001). After matching neighborhoods on off-premise density propensity, however, outlets per mile of roadway was not associated with gonorrhea rate while the association between density and crime remained (14 fewer violent crimes per 1000, p < 0.0001).

Conclusion: Structural confounding may be at play in the geographic association between off-premise density and gonorrhea rates in our sample, while the association between off-premise density and crime rate remains.

Learning Areas:
Public health or related research
Social and behavioral sciences

Learning Objectives:
1. Explain structural confounding and its role in multilevel contextual studies. 2. Define and differentiate between different methods for propensity score analysis. 3. Describe the direct and indirect roles of off-premise outlet density on health outcomes.

Keywords: Alcohol, Community

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I conduct research on neighborhood influences on health outcomes and other social epidemiogy topics.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.