Methods to measure the frequency of diseases in a population.
Incidence: The frequency of new cases of a disease that develop within a specified time period within a population.
Prevalence: The total number of cases of a disease present in a population at a given time.
Attack rate: The incidence of an infectious disease in a population over a short period of time.
Case fatality rate: The proportion of individuals with a disease who die from it.
Mortality rate: The frequency of death due to a specific disease or all-cause mortality within a population over a specified time period.
Standardization: Methods for adjusting disease rates for differences in population age, sex or other factors.
Risk: The probability of an individual developing a disease or condition over a specified time period.
Risk factors: Characteristics or factors that increase an individual’s probability of developing a disease or condition.
Protective factors: Characteristics or factors that decrease an individual’s probability of developing a disease or condition.
Outbreak Investigation: The process of investigating and managing outbreaks of infectious diseases.
Surveillance systems: Systems for tracking communicable and non-communicable diseases to enable detection and monitoring of trends, vaccination coverage, disease severity, and geographic distribution.
Case definitions: A standardized set of criteria used to identify cases of a particular disease.
Direct and Indirect measures of disease frequency: Methods for measuring disease frequency directly (e.g., through survey data, medical records) versus indirectly (e.g., through proxies such as death certificates or insurance records).
Age-specific, Sex-specific and Age-sex-specific Rates: Rates that are calculated separately for males and females or for specific age groups or both.
Global burden of disease: The quantification of morbidity and mortality from major diseases, injuries, and risk factors around the world.
Descriptive epidemiology: The study of patterns of disease distribution and frequency in populations.
Experimental studies: Studies that involve the manipulation of one or more factors to determine their effects on health outcomes.
Observational studies: Studies that observe and compare the relationship between exposure to a risk factor and the occurrence of disease.
Health disparities/inequities: Differences in health outcomes between different populations due to factors such as socio-economic status, race/ethnicity or geographical location.
Primary, secondary and tertiary prevention: Strategies and interventions aimed at preventing the onset or progression of disease at various stages.
Public Health: The science and practice of promoting and protecting the health of populations.
Prevalence: This measure represents the percentage of people in a specific population who have a disease at a given point in time. It is calculated by dividing the number of people with the disease by the total population.
Incidence: This measure represents the number of new cases of a disease that occur in a population over a specified period. It is typically expressed as a rate, such as the number of cases per 100,000 people.
Cumulative incidence: This measure represents the risk of developing a disease over a specific period. It is calculated by dividing the number of new cases by the total number of people at risk.
Attack rate: This measure represents the proportion of people in a population who develop a disease during an outbreak. It is calculated by dividing the number of new cases by the total number of people at risk during the outbreak.
Case-fatality rate: This measure represents the proportion of people with the disease who die from it. It is calculated by dividing the number of deaths from the disease by the total number of people with the disease.
Cause-specific mortality rate: This measure represents the number of deaths in a population due to a specific disease. It is typically expressed as a rate, such as the number of deaths per 100,000 people.
Age-specific rates: These measures represent disease frequency in specific age groups. They are calculated by dividing the number of cases or deaths in a specific age group by the total population in that age group.
Standardized rates: These measures represent the disease frequency in a population after adjusting for differences in age, sex, or other factors that may affect disease risk. They are typically expressed as a rate per 100,000 people.
Relative risk: This measure represents the likelihood of developing a disease in one group compared to another. It is calculated by dividing the incidence rate in one group by the incidence rate in another group.
Odds ratio: This measure represents the odds of developing a disease in one group compared to another. It is calculated by dividing the odds of developing the disease in one group by the odds in another group.