Evidence-based public health practices: challenges for health needs assessments in disasters.

Media coverage and the outpouring of public generosity in response to disasters often pressure institutions or organisations to act immediately without clear evidence. While it is critical to respond quickly to save lives and prevent suffering, obtaining valid information on which to make evidence-based, appropriate, and relevant relief decisions is just as important. Developed countries have better technology and equipment to assist with postdisaster data collection, with satellite surveillance providing information on population density, crop growth, and even troop movement in conflict areas. On the other hand, in low-income societies technology is not as accessible. Instead, post-disaster health needs assessments are based on quick, on-site manual surveys, which provide simple descriptions of the population profile and the health consequences of disaster/displacement.