A Department of Homeland Security Center of Excellence led by the University of Maryland

Quantitative Index of the Public Health Impacts of Terrorism

Quantitative Index of the Public Health Impacts of Terrorism


Project Details


This project conducted time series analyses of health data beginning five years (by month, when possible) before high profile terrorist attacks in New York (World Trade Center, 2001) and  Madrid (Madrid commuter trains, 2004) and ending two or more years after, depending on the timing of the event. The results sought to show which of the various indicators are most consistently sensitive to the impact of terrorism. These indicators can then be combined into a summary quantitative index that can be used to monitor the likely impact of future (or other past) events.

Primary Findings: 

Past research provides evidence for trajectories of health and wellness among individuals following disasters that follow specific pathways of resilience, resistance, recovery, or continued dysfunction. These individual responses are influenced by event type and pre-event capacities. The investigators identified terrorist attacks that could potentially impact population health rather than only selected individuals within the areas of the attacks. They chose to examine a time series of population birth outcomes before and after the terrorist events of the New York City (NYC) World Trade Center (WTC) attacks of 2001 and the Madrid, Spain train bombings of 2004 to determine if the events affected maternal-child health of those cities and, if so, for how long. For percentages of low birth weight (LBW) and preterm births, research found no significant effects from the WTC attacks in NYC and transient effects on rates of LBW and preterm births following the bombings in Madrid.

Researchers did find a significant positive and sustained effect on the infant mortality rate in NYC following the WTC attacks. There were no effects on any of the indicator variables in the comparison regions of New York State and the remainder of Spain. Population maternal-health in New York and Madrid was affected by the terrorist attacks in those cities. Short-term effects on LBW and preterm birth rates in Madrid and long-term effects on infant mortality rates in NYC were found when quarterly data were analyzed from 1990 through 2008/9. These findings raise questions about chronic changes in the population's quality of life following catastrophic terrorist attacks. Public health should be monitored and interventions designed to address chronic stress, as well as environmental and socioeconomic threats beyond the acute aftermath of events.


Investigators studied two terrorist events -- the 9/11/01 World Trade Center attacks in New York City and the 2004 train bombings in Madrid, Spain. The study was designed to utilize the trajectories of health model to determine if it translates to population health. Researchers used quarterly incident birth outcome data (rates of low birth weight, preterm births and infant mortality) from 1990 through 2008/2009 and conducted interrupted time series analyses with the event as the independent variable to determine if there were short- or long-term changes in the rates as a result of the event. They also collected similar rates for the remainders of New York state and Spain to use as comparison groups in the study.


Project Period: 
June 2008 to October 2011