Epidemiology intro Flashcards
Define exposure in epidemiology
Any factor that may influence the outcome
Define outcome
The disease or event or health related state understudy
What is observational epidemiology
Describe patterns of health and disease without intervening to change the factors that influence them.
Used to identify associations but not causation
What is interventional epidemiology
Assess effects of specific interventions at a community or hospital level
Define prevalence
Number of existing cases in a population at a designated time.
How do you calculate prevalence?
No of cases in population/ no of people in population
Prevalence= incidence x average disease duration
What is the benefit of identifying prevalence in a population?
Useful for assessingthe burden of disease in a population
What is point prevalence>
The proportion of people in a defined population that has the outcome understudy at a specific point in time
What type of conditions are best measured by point prevalence?
Long lasting conditions like schizophrenia
What type of conditions are best measured by period prevalence?
Episodic conditions like back pain
What is period prevalence>
Proportion of people in a defined population that has the outcome understudy over a defined period of time
Define incidence
Number of new cases of disease portrayed in two measures risk and rate.
Define incidence risk
The number of new cases in a period/ population INITIALLY at risk
What type of population is incidence risk looking at?
Static populations
Define incidence RATE
The number of new cases of disease in a specific period/ the number of person years at risk
