Exam Questions With Complete
Solution
.accurate assessment of exposure status - Answer-prospective cohort study
.aggregate - Answer-is a defined population.
.analytic study - Answer-consists of observational and experimental. Observational include case control and
cohort. Experimental includes random control trial (typically for new drug testing), field trial (conducted on
those who have a high risk of obtained a disease), and community trial (research is conducted on an entire
community or neighborhood). Test a hypothesis.
.anxiety about stability of exposure status - Answer-prospective cohort study
.Are you able to discuss "surveillance" and its relationship to "causation"? - Answer-is the ongoing systematic
collection, analysis, and interpretation of health data essential to the planning, implementation, and evaluation
of public health practice closely integrated with the timely dissemination of these data to those who need to
know. Passive surveillance involves using data to look at reportable diseases while active involves using
individuals such as project staff interviewing physicians about cases. Using surveillance can help identify the
causation of diseases particularly in a specific population.
.Can you explain what "descriptive epidemiology" means? What is the purpose? How is it used? - Answer-It
covers time place and person.
First, by looking at the data carefully, the epidemiologist becomes very familiar with the data. He or she can see
what the data can or cannot reveal based on the variables available, its limitations (for example, the number of
records with missing information for each important variable), and its eccentricities (for example, all cases
range in age from 2 months to 6 years, plus one 17-year-old.).
Second, the epidemiologist learns the extent and pattern of the public health problem being investigated —
, which months, which neighborhoods, and which groups of people have the most and least cases.
Third, the epidemiologist creates a detailed description of the health of a population that can be easily
communicated with tables, graphs, and maps.
Fourth, the epidemiologist can identify areas or groups within the population that have high rates of disease.
This information in turn provides important clues to the causes of the disease, and these clues can be turned
into testable hypotheses.
.Can you talk about the ways bias shows up in a study design (such as, selection bias) etc? - Answer-Selection
bias occurs when subjects in a sample are not representative of the population of interest. For example,
selecting only males for a study is not representative of the whole population. Informational bias can occur
when information is not complete or may be inaccurate. For example, blood pressure reading taken from cuffs
that are too small.
.Case-control study - Answer-investigates relationship between potential risk factors and disease.
examines the possible relationship of an exposure to getting a certain disease: a group of individuals with the
disease (cases) are compared to a group of people without the disease (controls). This study examines
relationships between potential risks factors where disease X (cases) with a sample without disease (X) controls
are compared with respect to their exposure to risk factors.
example: relationship of smoking to development of coronary heart disease.
1. start with people with Coronary heart disease (case
2. next, people without coronary heart disease (controls)
3. next identify the % of each group that used cigarettes and compare results; analyze the data
.Case-control study - Answer-selection of subjects by status: disease
info collected oh exposure: past
info collected on disease: current
.Case-control study - Answer-Used to study rare diseases. Used to study multiple exposures that may have a
single outcome. Participants are selected based on outcome status. Case- subjects have the outcome of
interest. Control-subjects do not have the outcome of interest. Used when the outcome of interest is rare,
multiple exposures may have a single outcome, and funding or time is limited.