Measuring + Describing Disease Flashcards
(31 cards)
What is epidemiology?
How often diseases occur in different groups of people + why
(Study of the distribution + determinants of health related states or events in specified populations + application of this study to the control of health problems)
What is endemic disease ?
Disease that resides in a population
What is epidemic disease ?
Disease that befalls a population
Who is known as the father of epidemiology? Why?
John Snow - prevented prevented spread of cholera in 1854
What are the 3 types of disease prevention?
→ primary
→ secondary
→ tertiary
What is primary prevention of disease?
→ before onset of disease
→ control of exposure to risk factors
What is secondary prevention of disease?
→ slows progression of disease
→ application of available measures to detect early departures from health and to introduce appropriate treatment and interventions
What is tertiary prevention of disease?
→ enables return to functioning after insult
→
What prevention does our health care service focus on?
→ secondary
→ tertiary
What is “exposure” in epidemiology terminology?
→ variable that we are trying to associate with a change in health status
→ independent variable
→ e.g. a drug, behaviour or demographic characteristic
What is “outcome” in epidemiology terminology?
→ the hypothetical result of being exposed to a particular variable
→ dependent variable
→ e.g. survival, mortality rates, hospitalisation, etc.
What is a demographic transition model?
measures birth rate, death rate and total population over time, or 5 stages
What is a epidemiologic transition model?
measures birth + death rates over 4 stages of demographic transition
What was the first stage of epidemiologic transition?
pestilence + famine (pre-industrial revolution, up to 1800s) → urbanisation → constraints on food supply → high birth + mortality rate → low life expectancy at birth
What was the second stage of epidemiologic transition?
receding pandemics (1800s-1900s)
→ agricultural development = improves nutrition
→ life expectancy increases
→ water, sanitation, hygiene
→ vaccination emerges
→ natural population increase as mortality rates decline
What was the third stage of epidemiologic transition?
degenerative + man-made diseases (1950s - 2010s)
→ crude birth rate
→ lifestyle factors + NCDs predominate
→ environmental + global determinants drive obesity + other risk factors
→ tech = less physical labour
→ addiction + violence emerge
What was the fourth stage of epidemiologic transition?
delayed degenerative diseases + emerging infections (2010s onwards)
→ health technology defer morbidity but increases financial cost
→ emerging zoonotic diseases
→ inequalities within + between countries
What are the measures of frequency?
→ odds
→ prevalence
→ cumulative incidence
→ incidence rate
What is the definition of odds?
the probability of an event to its complement
e.g. ratio of no. who have disease to no. who don’t
How are odds calculated?
odds = no. of people with disease/no. of people without disease
What is the definition of prevalence?
proportion of individuals in a population who have the disease or attribute of interest at a specific timepoint
How is prevalence calculated?
prevalence = no. of ppl with disease / total no. of people in population
What is cumulative incidence?
proportion of the population with a new event during a given time period
How is cumulative incidence calculated?
no. new cases during period of interest / no. of disease-free individuals at start of time period
