Question

Define the role of descriptive epidemiology.

Analyze specific host and environmental factors that may increase risk of disease susceptibility.

Distinguish between disease (outcome) status and exposure status variables

Describe the strengths of controlled clinic trials.

Distinguish between disease (outcome) status and exposure status variables.

Answer 1

1. Descriptive epidemiology provides a way of organizing and analyzing data on health and disease in order to understand variations in disease frequency geographically and over time and how disease varies among people based on a host of personal characteristics

2. Environmental factors are also potentially modified by genetics, and may act to increase or decrease risk of disease. The age is the greatest risk factor for AD and dementia. Because the incidence of AD and dementia increase essentially exponentially with age, the increase is likely not due to age itself, but to the cellular effects of aging coupled with the age-related penetrance of genetic factors.

3. Disease (outcome) status

Some participants have cancer (cases) and some do not (controls). The disease status is used to select the sample. Those with the disease are cases and controls are sampled from a population of disease-free individuals.

Exposure status variables

The exposure that varies among both cases and controls, i.e. the exposure status variable that is being tested to see if there is a link between it and the outcome of interest (Pancreatic Cancer), is a lifestyle variable like consumption of alcohol, tea, or coffee. Exposure to each life style variable is measured against outcome.

4.

A well designed controlled trial provides the strongest epidemiological evidence of any study design about the effectiveness and safety of a given intervention.

Clear temporal sequence - exposure clearly precedes outcome.

Can measure disease incidence and multiple outcomes.

Enables blinding and therefore minimizes bias.