This lesson introduces how epidemiologists describe the amount of disease in a community and how ratios and proportions summarize population data. These concepts help public health teams recognize unusual patterns and plan interventions.
A disease’s frequency is interpreted in relation to what is normally expected in a population and place.
These classifications help officials compare observed cases with the expected pattern and choose a suitable public health response.
All flashcards
Endemic disease level
The continual, usual presence of a disease in a defined area; it represents baseline occurrence.
Proportion
A ratio in which the numerator is included in the denominator, describing a part of a whole.
Prevalence
The proportion of a population with a condition at a specified point or during a defined period.
Case-fatality rate
The proportion of people with a particular disease who die from it; it indicates disease severity.
Confounding
Distortion of an exposure-outcome association by a factor related to both exposure and outcome.
Quiz questions
In a case-control study, what does the odds ratio compare?Answer: Exposure odds among cases with exposure odds among controls.
What is the denominator used to calculate the infant mortality rate?Answer: Live births during the same period as the deaths.
What does a 95% confidence interval mean under its statistical assumptions?Answer: The method would capture the target parameter in about 95% of repeated intervals.
Which Bradford Hill consideration is essential for a causal relationship?Answer: The exposure must precede the disease.
What does attributable risk estimate among exposed people?Answer: The proportion of disease associated with the exposure, under stated assumptions.
Based on Population Health for Nurses by Jessica Ochs, Sherry L. Roper, Susan M. Schwartz (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.