The use of epidemiological tools in conflict-affected populations: open-access educational resources for policy-makers

Table of Contents

1. Welcome
2. Introduction: Epidemiology in crises
3. Ethical issues in data collection
4. Need for epidemiologic competence
5. Surveys - Introduction
6. Surveys - Description of sampling methods
7. Surveys - Sampling error, bias, accuracy, precision, & sample size
8. Surveys - Resources required for surveys
9. Surveys - Critiquing survey reports
10. Surveillance - When to do surveillance
11. Surveillance - Methods
12. Surveillance - Common problems
13. Programme data
14. Rapid assessment
15. Mortality - Indicators and their measurement
    1. Why measure mortality
    2. Parts of mortality rate
    3. Formats for mortality rate
    4. Types of mortality rates
    5. Mortality rates for children
    6. Number of excess deaths
    7. Measurement of causes of death in surveys
16. Mortality - Data sources
17. Mortality - Interpretation and action
18. Nutrition - Introduction and background
19. Nutrition - Indicators and their measurement
20. Nutrition - Data sources
21. Nutrition - Interpretation and action
22. Health services
23. Vaccination programmes
24. Water supply, sanitation, and shelter
25. Violence
26. Presentation of results
27. Formulating conclusions and recommendations
28. Dissemination and action

Measurement of causes of death in surveys

(go to Outline)

In developed countries, the health worker who cared for the patient just before death or attended the death completes a death certificate on which the cause of death is recorded. This mechanism is not present in populations in which a large proportion of deaths are unattended or in which death registration is very incomplete. In such populations, one way to determine cause of death is to use verbal autopsy.

Verbal autopsy consists of a lengthy questionnaire which asks surviving family members about the signs and symptoms experienced by the deceased person just before death. Physicians reviewing these questionnaire responses can then make a judgement regarding the cause of death.

Completion of verbal autopsy questionnaires requires lengthy interviews, up to 1.5 hours, and their evaluation requires a detailed review by a team of physicians. This is not practical for survey assessments in emergency-affected populations. Nonetheless, some emergency assessment surveys ask only one or a few questions to distinguish between violent and non-violent deaths. Although not yet validated, such questions may be able to distinguish between those deaths from violence and those not from violence.

In addition, some childhood illnesses, such as measles and neonatal tetanus, have relatively distinctive presentations which mothers may recognize. There may even be a specific word in the local language for such illnesses. Again, although not validated, surveys may be able to gather accurate data on these diseases by using this local term.

There are several studies of the validity of various verbal autopsy algorithms. One of the larger studies of verbal autopsy for children is "A Standard Verbal Autopsy Method for Investigating Causes of Death in Infants and Children" (click here to open the document), published by the World Health Organization.

New efforts to standardize verbal autopsy methods may result in greater validity and comparability of studies using verbal autopsy (click here to open Verbal Autopsy Standards: Ascertaining and Attributing Cause of Death.)