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Community Study: Rapid community needs assessment using modified cluster sampling methods


To rapidly obtain population-based estimates of needs in the early aftermath of a mass casualty event, with severe property damage affecting at least one neighborhood. The assessment should be designed to benefit the affected population by providing up-to-date, ongoing assessment information, such as the location and/or availability of sites for medical treatment, counseling services, food and supply distribution, and other services. The findings will be useful in guiding relief efforts.

Who would use the data?

Disaster relief organizations, health departments, local and state governments, law enforcement, utility companies, the news media, and other organizations involved in coordinating early response efforts.


Hlady WG, Quenemoen LE, Armenia-Cope RR, et al. Use of a modified cluster sampling method to perform rapid needs assessment after Hurricane Andrew. Annals of Emergency Medicine 1994;23:719-25.

Centers for Disease Control and Prevention. Community needs assessment of lower Manhattan residents following the World Trade Center attacks–Manhattan, New York City, 2001. MMWR 2002;51(10).

Questions of interest:

  • What are the demographic characteristics of affected households, including the mean number of residents before and after the event, the number of young children, and the number of adults ages 64 years or older?
  • What are the general health and mental health, and medical needs of affected households?
  • What type of damage did homes, businesses, and critical community services sustain?
  • Which services (e.g., electricity) need to be restored most urgently?
  • If assistance has been received, from what sources? Was it effective?


  • Target population: Persons directly affected by the mass casualty event who are living in the community. These would include:
    • Directly exposed individuals who were physically present at the time of the event.
    • Immediate family members of persons directly exposed to the event.
    • Indirectly exposed individuals who were not physically present at the time of the assault, but were indirectly affected physically, emotionally, or socially by the event.
    • Emergency workers/first responders who engaged in evacuation and recovery efforts, patient triage, or onsite medical or first aid treatment.
  • Initial data collection would focus on the geographic areas reported by local officials to be most severely affected.
  • Study design: Cross-sectional survey of households, commercial establishments, and public buildings.
  • Sampling plan: A minimum of 30 clusters would be systematically sampled from the area of interest and from households within each cluster identified using the methods described in Hlady et al., 1994.
  • Interview methods: Interviewer teams visit households, commercial establishments, and/or public buildings, and interview adult members of all such sites selected for inclusion. Interviewers also provide information about the location of medical treatment and supply distribution sites, and pass on preventive health messages including injury prevention.
  • Sample questions: How many and what percentage of surveyed households reported the following?
    • Not enough food
    • No running water
    • No electricity
    • No heat/air conditioning (in temperature extremes)
    • No functioning toilet
    • No telephone
    • No car or truck
    • Injured resident(s)
    • Ill resident(s)
    • Resident(s) in need of medical care
    • Resident(s) unable to obtain needed medications
    • Resident(s) in need of counseling
    • Resident(s) with special needs
    • Displaced from home
  • Time frame for initiating study: After ground transportation is restored, or approximately 3 and 10 days after the event for severely affected areas. Assessments of less severely affected areas would be phased in as possible within this time frame.

Potential partners/collaborators:

  • State and local health departments
  • Local university researchers, especially schools of public health
  • CDC, including NCEH and NCIPC staff
  • Law enforcement
  • American Red Cross
  • FEMA
  • Salvation Army

IRB needed:

N/A (this is not research)

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