Chamberlain College of Nursing

NR503: Population Health, Epidemiology, & Statistical Principles

Relative Risk Calculations Worksheet Guidelines & Grading Rubric

Purpose:The purpose of this assignment is to help you understand and apply important counts, ratios, and statistics used in healthcare and epidemiological research. Use the formulas provided and carefully consider each calculation’s purpose and interpretation.

Course Outcomes:

• CO #3: Identify appropriate outcome measures and study designs applicable to various epidemiological subfields.
• CO #4: Apply commonly used measures of health risk.
• CO #6: Identify important sources of epidemiological data.

Due Date: Sunday, 11:59 p.m. (MT) at the end of Week 3 Total Points Possible: 50

Requirements:

1. Complete the Risk Calculation Worksheet located in Course Resources.
2. For each question, identify the correct answer.
3. Submit the worksheet to the DropBox by 11:59 p.m. MT Sunday of Week 3.

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Epidemiological Formulas and Statistics

Relative Risk Calculation

Parameter Definitions and Formulas:

1. Incidence=Number of New CasesPopulation at Risk\text{Incidence} = \frac{\text{Number of New Cases}}{\text{Population at Risk}}Incidence=Population at RiskNumber of New Cases​
2. RR=Incidence Rate in Exposed GroupIncidence Rate in Unexposed Group\text{RR} = \frac{\text{Incidence Rate in Exposed Group}}{\text{Incidence Rate in Unexposed Group}}RR=Incidence Rate in Unexposed GroupIncidence Rate in Exposed Group​
3. OR=(Odds of Disease in Exposed Group)(Odds of Disease in Unexposed Group)\text{OR} = \frac{\text{(Odds of Disease in Exposed Group)}}{\text{(Odds of Disease in Unexposed Group)}}OR=(Odds of Disease in Unexposed Group)(Odds of Disease in Exposed Group)​
4. Prevalence=Number of Existing CasesTotal Population\text{Prevalence} = \frac{\text{Number of Existing Cases}}{\text{Total Population}}Prevalence=Total PopulationNumber of Existing Cases​
5. AR=Incidence in Exposed Group−Incidence in Unexposed Group\text{AR} = \text{Incidence in Exposed Group} - \text{Incidence in Unexposed Group}AR=Incidence in Exposed Group−Incidence in Unexposed Group
6. PAR=Incidence in Total Population−Incidence in Unexposed GroupIncidence in Total Population\text{PAR} = \frac{\text{Incidence in Total Population} - \text{Incidence in Unexposed Group}}{\text{Incidence in Total Population}}PAR=Incidence in Total PopulationIncidence in Total Population−Incidence in Unexposed Group​
7. SD=∑(Xi−Xˉ)2N−1\text{SD} = \sqrt{\frac{\sum (X_i - \bar{X})^2}{N - 1}}SD=N−1∑(Xi​−Xˉ)2​​where XiX_iXi​ represents each value, Xˉ\bar{X}Xˉ is the mean of the values, and NNN is the number of values.
8. CI=Estimate±(Critical Value)×Standard Error\text{CI} = \text{Estimate} \pm \text{(Critical Value)} \times \text{Standard Error}CI=Estimate±(Critical Value)×Standard Error
9. P-value Definition: The probability of obtaining a result at least as extreme as the one observed, under the null hypothesis. Formula: Calculated through statistical tests (e.g., t-tests, chi-square tests).

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Guidelines for Completing the Worksheet:

• Read each question carefully. Identify which epidemiological measure or statistic is required.
• Apply the appropriate formula. Make sure to use the correct data for each calculation.
• Interpret the results. Consider what the calculated value means in the context of the question.
• Submit your completed worksheet. Ensure it is submitted to the DropBox by the deadline.

Grading Rubric:

• Accuracy of Calculations (20 points): Correct use of formulas and accurate results.
• Interpretation and Explanation (15 points): Clear and accurate interpretation of results.
• Presentation and Organization (10 points): Well-organized worksheet with clear calculations and explanations.
• Timeliness (5 points): Submission by the specified deadline.