Sexual Health | Public health | Introduction to Epidemiological Measures

Introduction to Epidemiological Measures
Session Overview
Description
This session will introduce you to the fundamental concepts of epidemiology that are used to measure the health of the population (rather than of individuals) and to assess the effectiveness of public health interventions.

Learning Objectives
By the end of this session you will be able to:

• Describe the importance of clearly defining cases in epidemiological studies
• Explain the need for denominators in epidemiological studies and why (and how) this should be calculated as 'person-time at risk' for cohort (longitudinal) studies
• Explain the difference between different measures of disease frequency (incidence and prevalence), how to calculate them and when to use them
• Explain the difference between different measures of exposure effect (including risk ratio and risk difference), how to calculate them and when to use them
• Describe the problem of confounding

Prerequisites
This session accompanies Module 16/Introduction to Epidemiological Study Design (260-0172)

Epidemiological studies seek to measure the occurrence of a health-related outcome of interest in populations, such as the frequency of a disease or death.

As such, it is important that a case, (in other words, an individual in the population who has the health-related outcome of interest) is clearly defined.

This session introduces commonly-used measures of disease frequency and measures of exposure effect that can be used to answer the questions of where, when and how much.

Worked examples illustrate how these measures can be calculated and notes are provided as to the appropriate use of these measures.