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
16. Mortality - Data sources
    1. Introduction
    2. Surveillance - Prospective death reporting
    3. Surveys (retrospective data collection)
    4. Recall period
    5. Determining the length of the recall period
    6. Data collection and the questionnaire
    7. Surveys - Quiz
    8. Surveys measuring mortality - Summary
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

Recall period

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1

In the diagram above, which deaths would be counted in the numerator of the crude mortality rate? a) John b) Maria c) Ahmed d) Lars e) Tatiana Correct. Only Ahmed, Lars, and Tatiana died during the recall period. The deaths of John and Maria occurred before the recall period began and therefore should not be included in the mortality rate calculated from the survey data. Incorrect. Ahmed, Lars, and Tatiana died during the recall period. Their deaths should be included in the numerator of the crude mortality rate. The deaths of John and Maria occurred before the recall period began and therefore should not be included in the mortality rate calculated from the survey data. Your answer has been saved.

Keep in mind that the survey respondent will have to accurately place in time a household death relative to the beginning of the recall period. Therefore, the recall period should be an easily remembered point in time, such as a large festival or holiday or a date on which something memorable occurred. Do not use arbitrary time periods, such as 3 months or 6 months. Most populations are not oriented enough to a western calendar to easily think of a date 3 or 6 months ago. Surveys using such recall periods risk overestimating mortality rates because people generally tend to remember traumatic events as having occurred more recently than they really did. This is called "telescoping."

The end of the recall period is usually the date of the interview.