HSA 535 Discussion Board WK 6 – DB2
A DISTINGUISHED POST INCLUDES: Student’s post indicates thoughtful analysis and provides valuable insight into the topic. Student thoroughly addresses all elements of the discussion prompt, and demonstrates an advanced knowledge of the topic. Student makes strong and precise connections to previous and/or current course content, or to real-life situations, in initial post.

Step #1: Write a post regarding the topic below:
“Study Designs in Epidemiology” Please respond to the following:

**After reviewing this week’s reading material, analyze the various study designs, and recommend the optimum design for studying an outbreak of seasonal flu in your home state. Provide support for your rationale.

**Analyze the pros and cons of using a case-control study design. Based on your analysis, suggest a way in which one might primarily use the case-control design to reduce bias in an outbreak study.

Step #2: PLEASE WRITE A SEPARATE RESPONSE TO EACH CLASSMATE. The response should be positive and not negative. Student responds with thorough and constructive analysis to the required number of peers, relating the response to relevant course concepts.

Classmates Response:
Professor Godson: respond to student’s post regarding same topic
Case-control studies are relatively simple to conduct. and are hence much cheaper. This design is especially useful for rare diseases It is also very suitable for diseases with a long latent period, such as cancer. However, case-control studies are less adept at showing a causal relationship. They are more prone to bias. Clinical data may be inadequate of incomplete, clinical cases are selective survivors. Case group may not be homogenous, criteria for diagnosis may differ.
What do you think ?
Godson

N D: respond to student’s post regarding same topic
After reviewing this week’s reading material, analyze the various study designs, and recommend the optimum design for studying an outbreak of seasonal flu in your home state. Provide support for your rationale.
Epidemiological studies can be classified as either observational or experimental. In experimental studies it is the studies in which all of the risk factors are controlled by the investigator while in observational studies is the studies in which the distribution or determinants of an outcome are examined without any attempt by the investigator to influence them. In experimental studies is the Randomized Controlled Trial (RCT) in which people are randomly allocated to receive one of several clinical interventions. One of these interventions is a standard of comparison or control. In observational study it consist of cohort study, case control, cross sectional and ecological (population based).
In a cohort study is a subsets of a defined population that can be identified that are, have been, or may in the future be exposed, or not exposed, to a factor that is thought to influence the probability of occurrence of a given disease or other outcome. A case control starts with the identification of individuals with the disease (or other outcome variable) of interest, and a suitable control group of individuals without the disease. The diseased group is called cases and the non-diseased group is called controls. Cases and controls are compared with respect to the occurrence of the exposure of interest. Cross sectional is the frequency of a particular exposure(s) and / or outcome(s) in a defined population is measured at a particular point in time. Ecological compares the exposure and outcome status of groups rather than individuals.

Case–control designs (also called ‘cumulative’ or ’classic’ case–control) offer an efficient alternative when the source population (i.e. the population from which cases arose) is large and/or the outcome rare. Exposures in cases are compared to exposures in a sample of the non-cases (i.e. the controls) drawn from the same at-risk population and the most common measure of association is the odds ratio (OR).
Analyze the pros and cons of using a case-control study design. Based on your analysis, suggest a way in which one might primarily use the case-control design to reduce bias in an outbreak study.
The advantage of case-control studies are quick and cheap and are particularly suited to the study of rare diseases as the diseased are selected at the outset of the study.
The disadvantages of case-control studies include
Difficulties in overcoming potential bias and confounding
• The successful selection of both cases and controls who are representative of their respective populations is often difficult.