Lee Joseph G L, Sun Dennis L, Schleicher Nina M, Ribisl Kurt M, Luke Douglas A, Henriksen Lisa
Department of Health Education and Promotion, College of Health and Human Performance, East Carolina University, Greenville, North Carolina, USA.
Department of Health Behavior, UNC Gillings School of Global Public Health, Chapel Hill, North Carolina, USA.
J Epidemiol Community Health. 2017 May;71(5):487-492. doi: 10.1136/jech-2016-208475. Epub 2017 Mar 1.
Evidence of racial/ethnic inequalities in tobacco outlet density is limited by: (1) reliance on studies from single counties or states, (2) limited attention to spatial dependence, and (3) an unclear theory-based relationship between neighbourhood composition and tobacco outlet density.
In 97 counties from the contiguous USA, we calculated the 2012 density of likely tobacco outlets (N=90 407), defined as tobacco outlets per 1000 population in census tracts (n=17 667). We used 2 spatial regression techniques, (1) a spatial errors approach in GeoDa software and (2) fitting a covariance function to the errors using a distance matrix of all tract centroids. We examined density as a function of race, ethnicity, income and 2 indicators identified from city planning literature to indicate neighbourhood stability (vacant housing, renter-occupied housing).
The average density was 1.3 tobacco outlets per 1000 persons. Both spatial regression approaches yielded similar results. In unadjusted models, tobacco outlet density was positively associated with the proportion of black residents and negatively associated with the proportion of Asian residents, white residents and median household income. There was no association with the proportion of Hispanic residents. Indicators of neighbourhood stability explained the disproportionate density associated with black residential composition, but inequalities by income persisted in multivariable models.
Data from a large sample of US counties and results from 2 techniques to address spatial dependence strengthen evidence of inequalities in tobacco outlet density by race and income. Further research is needed to understand the underlying mechanisms in order to strengthen interventions.
烟草销售点密度方面种族/族裔不平等的证据受到以下因素限制：（1）依赖单一县或州的研究；（2）对空间依赖性关注有限；（3）邻里构成与烟草销售点密度之间基于理论的关系不明确。
在美国毗邻地区的97个县，我们计算了2012年可能的烟草销售点密度（N = 90407），定义为每1000人口中普查区（n = 17667）的烟草销售点数量。我们使用了两种空间回归技术，（1）在GeoDa软件中采用空间误差方法；（2）使用所有普查区中心点的距离矩阵对误差拟合协方差函数。我们将密度作为种族、族裔、收入以及从城市规划文献中确定的两个表明邻里稳定性的指标（空置住房、租户占用住房）的函数进行研究。
平均密度为每1000人有1.3个烟草销售点。两种空间回归方法得出了相似的结果。在未调整的模型中，烟草销售点密度与黑人居民比例呈正相关，与亚洲居民、白人居民比例以及家庭收入中位数呈负相关。与西班牙裔居民比例无关。邻里稳定性指标解释了与黑人居住构成相关的不成比例的密度，但多变量模型中收入不平等仍然存在。
来自美国大量县的样本数据以及两种解决空间依赖性技术的结果，强化了烟草销售点密度在种族和收入方面存在不平等的证据。需要进一步研究以了解潜在机制，从而加强干预措施。
