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
17. Mortality - Interpretation and action
18. Nutrition - Introduction and background
19. Nutrition - Indicators and their measurement
    1. Introduction to anthropometry
    2. Anthropometric indices
    3. Reference populations
    4. Calculation of percent of median
    5. Oedema
    6. Calculation of z-scores
    7. Adults and body mass index (BMI)
    8. Micronutrients - Clinical indicators
    9. Micronutrients - Biochemical indicators
    10. Calculating prevalence
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

Oedema

(go to Outline)

Oedema is fluid collection in the tissue. In some severely malnourished people, fluid leaks out of the blood vessels into the tissues causing a particular kind of swelling, called pitting oedema. Examination for pitting oedema consists of applying pressure with the thumb to the back of the foot or front of the lower leg for 3 seconds, then releasing. If a dent is seen or felt, pitting oedema is present. The examiner must press for at least 3 seconds and clearly see or feel a dent remaining after the pressure is released. Pitting oedema must be present on BOTH feet to be caused by malnutrition. There are many other causes of pitting oedema in only one foot. Pitting oedema if very often over-diagnosed by survey team examiners which leads to spurious conclusions about the prevalence of severe acute protein-energy malnutrition.

The photo on the left shows a child's foot with pitting oedema; on the right is an adult's foot with pitting oedema.