Assignment
The governor of your state approached you and your team in the state's Public Health Department to assess the two screening tools used to detect the presence of a new sexually transmitted disease (D). You and your team are tasked to figure out which screening tool the state needs to purchase to identify those who have the disease D, and to prevent rapid spread of the disease. The researchers who discovered D state that ongoing investigation points to several factors that appear to magnify the spread of this disease. What type of information or data do you need to start your own investigation? (Hint: Please make any assumptions you need about the sample, population, two screening tests, and the disease - but you need to clearly state what these assumptions are.) How would you and your team go about assessing the two screening tools? Are there any interactions and/or confounders associated with this disease? How would you measure and/or control for them? What statistical procedures would you employ to figure out which statistical test would be better?
Please feel free to use the Open Source Epidemiological Statistics for Public Health tool for your screening tool assessment, available at http://www.openepi.com/DiagnosticTest/DiagnosticTest.htm
In your response posts, consider and address the following questions:
1. What do you think about the assumptions that your classmates made about the sample, population, screening tests, and disease?
2. How would you asses their logic on their decision of the screening tool?
3. Do you have specific reasons to agree or disagree with your classmates' assessments about confounders and/or interactions in this scenario?
Competencies:
1. Derive the tools to assess, develop, implement, and evaluate public health programs, systems, and partnerships.
7. Collect, assess, analyze, and construct definitions, data sources, principles, and limitations related to the epidemiology of public health.
8. Calculate, synthesize, and communicate epidemiological information to a variety of audiences.
Learning Objectives:
1. Decide on a screening tool to address a public health problem.
2. Interpret prevalence, incidence, odds ratio, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of a screening tool.
3. Describe 2x2 contingency tables.
4. Identify confounders and effect modifiers.
5. Define and interpret prevalence, incidence, and odds ratio.