Epidemiologic studies of behavioral health following the Deepwater Horizon oil spill: limited impact or limited ability to measure?

Two large-scale epidemiologic federal surveys conducted in the Gulf Coast following the Deepwater Horizon oil spill and intended to measure its impact on mental disorders and substance use found less dramatic results than had been anticipated. However, several smaller-scale studies conducted shortly after the spill did find increases in the prevalence of certain psychological problems among individuals surveyed. Previous federal studies conducted following two disasters-the destruction of the World Trade Center (WTC) and Hurricanes Katrina and Rita-found few statistically significant changes in behavioral disorders in the wake of those events, except for individuals displaced from their homes by Katrina for 2 weeks or more. In this commentary, the authors discuss questions raised by these mixed results regarding the limitations of such studies, the behavioral health impact of the Deepwater Horizon spill compared to disasters causing more widespread loss of life and destruction of property, and the ways in which data collection following disasters might be improved to benefit public health planners.