Mialon Hugo M, Nesson Erik T, Samuel Michael C
Department of Economics, Emory University, Atlanta, GA, USA.
Department of Economics, Ball State University, Muncie, IN, USA.
Health Econ. 2016 Mar;25(3):292-313. doi: 10.1002/hec.3140. Epub 2014 Dec 29.
Public health officials have cited methamphetamine control as a tool with which to decrease HIV and other sexually transmitted infections, based on previous research that finds a strong positive correlation between methamphetamine use and risky sexual behavior. However, the observed correlation may not be causal, as both methamphetamine use and risky sexual behavior could be driven by a third factor, such as a preference for risky behavior. We estimate the effect of methamphetamine use on risky sexual behavior using monthly data on syphilis diagnoses in California and quarterly data on syphilis, gonorrhea, and chlamydia diagnoses across all states. To circumvent possible endogeneity, we use a large exogenous supply shock in the US methamphetamine market that occurred in May 1995 and a later shock stemming from the Methamphetamine Control Act, which went into effect in October 1997. While the supply shocks had large negative effects on methamphetamine use, we find no evidence that they decreased syphilis, gonorrhea, or chlamydia rates. Our results have broad implications for public policies designed to decrease sexually transmitted infection rates.
公共卫生官员将甲基苯丙胺管控视为降低艾滋病毒及其他性传播感染的一种手段，这是基于之前的研究发现，即甲基苯丙胺使用与危险性行为之间存在很强的正相关。然而，观察到的这种相关性可能并非因果关系，因为甲基苯丙胺使用和危险性行为可能都由第三个因素驱动，比如对危险行为的偏好。我们利用加利福尼亚州梅毒诊断的月度数据以及所有州梅毒、淋病和衣原体诊断的季度数据，来估计甲基苯丙胺使用对危险性行为的影响。为规避可能的内生性问题，我们利用了1995年5月美国甲基苯丙胺市场出现的一次重大外部供应冲击，以及1997年10月生效的《甲基苯丙胺管制法》引发的后续冲击。虽然供应冲击对甲基苯丙胺使用产生了很大的负面影响，但我们没有发现它们降低梅毒、淋病或衣原体感染率的证据。我们的研究结果对旨在降低性传播感染率的公共政策具有广泛影响。
