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dot Using Statistical Measures
dot Frequency Distributions
 - Ratios
 - Proportions
 - Rates
dot  - Incidence Rates
 - Rate Ratios
 - Prevalence Rates
dot  - Crude Rate
 - Cause-Specific Rate
 - Other Specific Rates
dot  - Relative Risk
 - Odds Ratio
dot Outbreak Exercises
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Statistical Measures

Morbidity Frequency Measures

  • Several standard measures are used to measure and describe the frequency of disease. Person with rash
  • Each measure has its appropriate uses, depending on the situation and the information available to the epidemiologist.
  • The two main types of rates are:
    • incidence
    • prevalence

Incidence Rates

  • Incidence rates are the most common way of measuring and comparing the frequency of disease in populations.
  • Incidence is a measure of risk.
  • When Population A has a higher incidence of a disease than Population B, we can say that Population A has a higher risk of developing the disease than Population B. If it is a lot higher, we could say that Population A is a high-risk group for that disease.