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
    1. Inherent problems
    2. Incomplete reporting
    3. Biases from the health system
    4. Changes in the surveillance system
    5. Denominator problems
    6. Assessing quality of data
13. Programme data
14. Rapid assessment
15. Mortality - Indicators and their measurement
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

Inherent problems

(go to Outline)

Surveillance, even if done very well, is NOT very good at doing some things:

• Providing the data necessary to calculate the population prevalence of some health condition

Remember, prevalence is the number of people with the disease divided by the total number of people. Surveillance often gives you only information about cases of disease because the data reporters are those who take care of sick people. As a result, you do not have the population denominator with which to calculate a incidence or prevalence rate.

• Providing health information where few people have access to or seek health care services

If data reporters are health care providers and most people don't come for health care, you will never hear about most cases of disease.

• Gathering detailed data on many health conditions

The health care workers who act as data reporters are often very busy and cannot write down a lot of data on each patient. As a result, you should only ask them to collect only the most essential data for you.