Chapter 8 Flashcards
Epidemiology would be a primary tool used by the nurse scientist for researching which topic?
a. Experiences of cancer care services
b. Contributing factors to childhood obesity
c. Morbidity statistics
d. Social characteristics and traits of healthy older persons
b. Contributing factors to childhood obesity
Epidemiology is exactly the field that looks at contributing factors—the elements that influence, increase, or relate to the occurrence of disease or poor health outcomes in a population.
In which of the following activities does the community health nurse (CHN) act in the role
of a nurse epidemiologist?
a. Eliciting the health history of a client presenting with an illness
b. Performing a physical assessment of an ill client
c. Providing treatment and health education to a client with a disease
d. Evaluating the number of clients presenting with similar diseases
d. Evaluating the number of clients presenting with similar diseases
Blue
Blue
Which model best explains the reasons why homeless individuals are at increased risk of disease as a result of multiple agent, host, and environmental factors?
a. The web of causality
b. The epidemiological triangle
c. The levels of prevention
d. The Health Promotion Model
a. The web of causality
The Web of Causality (or Web of Causation) is a conceptual model used in public health and epidemiology to explain how multiple interacting factors contribute to disease or health outcomes. Instead of a single cause leading to a disease, this model acknowledges that multiple interconnected factors (biological, social, economic, and environmental) influence health.
Why is it called a “Web”?
• Imagine a spider web where multiple strands are connected.
• If you pull one strand, it affects the others—this represents how different risk factors are interconnected.
• Similarly, diseases (like homelessness-related illnesses) result from multiple factors interacting, rather than a single direct cause.
Why is this Relevant to Homelessness?
Homeless individuals are at increased risk of disease due to multiple interwoven factors, such as:
• Social determinants of health (poverty, lack of healthcare access).
• Environmental exposures (poor sanitation, harsh weather conditions).
• Behavioral risks (substance use, lack of nutrition).
• Psychological stress (mental illness, trauma).
• Infectious disease risks (higher exposure to communicable diseases due to crowded shelters or unsanitary living conditions).
Why Not the Other Models?
• (b) Epidemiological Triangle – Explains disease causation through Agent, Host, and Environment, but is more applicable to infectious diseases rather than complex social health issues.
• (c) Levels of Prevention – Refers to primary, secondary, and tertiary prevention strategies, not causal relationships.
• (d) Health Promotion Model – Focuses on personal health behaviors rather than complex multi-factorial causes.
Key Takeaway:
The Web of Causality helps explain why homelessness leads to poorer health outcomes, showing that it’s not just one cause (e.g., lack of housing) but a complex interplay of multiple factors that create health risks.
Which actions could be taken by the community health nurse (CHN) who wishes to
provide secondary prevention to decrease the incidence of obesity in elementary school
children?
a. Giving a presentation on the importance of exercise and physical fitness
b. Designing a game in which students need to make healthy food choices
c. Weighing students to identify those who are overweight
d. Putting students on a diet if they weigh more than 20% of their ideal weight
c. Weighing students to identify those who are overweight
What is a community health nurse (CHN) implementing when advising a client with
osteoporosis to have three servings of milk or dairy products daily?
a. Primary prevention
b. Secondary prevention
c. Tertiary prevention
d. Treatment, but not prevention
c. Tertiary prevention
What would be the best choice for the nurse researcher who wishes to identify the long-term benefits and risks of a treatment for hyperlipidemia?
a. A cross-sectional study
b. An ecological study
c. A clinical trial
d. A retrospective analysis
c. A clinical trial
Clinical trials are your bestie when it comes to testing treatments over time. You control what happens, you assign groups, and you get to say cool things like “statistically significant” without lying.
Which action proposed to prevent problems related to coronary artery disease (CAD) in a region with a high prevalence is most likely to have positive outcomes?
a. Introducing heart health information in the curriculum as early as Grade 1, presentations on diet and exercise for the community at large, and special
education sessions for high-risk populations
b. Providing online activities related to the prevention of cardiac disease, smoking cessation programs, and blood pressure screenings
c. Distributing handouts about age-appropriate games, self-assessments, and educational materials on heart-healthy lifestyles, availability of community
screenings for hyperlipidemia in persons age 35 years and older, and walking programs for those affected by CAD
d. Enrolling clients with CAD into cardiac rehabilitation programs, routinely evaluating the effectiveness of CAD treatment regimens, and participating in clinical trials that evaluate interventions for those diagnosed with CAD
c. Distributing handouts about age-appropriate games, self-assessments, and educational materials on heart-healthy lifestyles, availability of community
screenings for hyperlipidemia in persons age 35 years and older, and walking programs for those affected by CAD.
People with immune deficiencies may have a negative tuberculosis (TB) skin test (Mantoux), even though they are infected. Which of the following measurements will the CHN conclude to be low when the TB skin test is given to persons with acquired immune deficiency syndrome (AIDS)?
a. Positive predictive value
b. Reliability
c. Sensitivity
d. Specificity
c. Sensitivity
That’s right, it’s sensitivity.
Here’s the rundown:
• Sensitivity = the ability of a test to correctly identify those who have the disease. So if sensitivity is low, the test misses people who are sick and gives them false negatives.
• Specificity = the ability to correctly identify those who do not have the disease. So it’s about avoiding false positives. Not the issue here.
• Reliability = how consistently the test gives the same result over time. Cool, but also not relevant here.
• Positive Predictive Value = the chance that someone who tests positive actually has the disease. Again, interesting, but not the culprit when false negatives are the problem.
So in people with AIDS, their immune systems are like, “Test? I don’t know her,” and the TB skin test fails to react—leading to low sensitivity
The CHN can enhance the sensitivity and specificity of a test by using its predictive value. Which one of the following best defines positive predictive value?
a. The proportion of persons with a negative test who are actually disease-free
b. The variation inherent in the trait being measured
c. Any inconsistency in the testing instrument
d. The proportion of persons with a positive test who actually have the disease
d. The proportion of persons with a positive test who actually have the disease
Positive Predictive Value (PPV)
= Of all the people who tested POSITIVE, how many actually HAVE the disease?
That’s it.
That’s the whole thing.
It’s like asking: How trustworthy is a positive result?
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In your question:
• d. “The proportion of persons with a positive test who actually have the disease”
= Exactly the definition of PPV. This one is correct. Gold star. No notes.
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Let’s slap down the wrong options:
• a. “…with a negative test who are actually disease-free”
→ That’s Negative Predictive Value (NPV). Wrong party.
• b. “Variation in the trait being measured”
→ That’s just biological chaos. It has nothing to do with PPV. That’s like blaming the thermometer because you’re weirdly warm.
• c. “Inconsistency in the testing instrument”
→ That’s reliability or lack thereof. If the test is flaky. We’re not judging its mood here, we’re judging its accuracy in calling people sick
A community health nurse (CHN) determines that out of 8,000 women screened for breast cancer, 35 have previously been diagnosed with a cancer event and 20 are newly diagnosed with a cancer event. What is the prevalence rate in this group?
a. 55
b. 0.7
c. 70%
d. 55/8,000
d. 55/8,000
Step 1: Know what prevalence means.
Prevalence = total number of existing cases (old + new)
in a population at a given time.
It doesn’t care if it’s new or old—it’s just counting how many people have it.
It’s the party guest list, not who just walked in.
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Step 2: Pull the numbers from the question.
• 35 women had previous cancer (old cases)
• 20 women were newly diagnosed (new cases)
• Total population screened = 8,000 women
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Step 3: Add your cases.
35 (existing) + 20 (new) = 55 total cases
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Step 4: Divide by the population.
Prevalence = 55 / 8,000
Boom. That’s why the correct answer is:
d. 55/8,000
(If you actually wanted a decimal: 0.006875, or 0.6875%)
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Quick Comparison:
• Prevalence = ALL current cases (old + new)
• Incidence = Only the new cases (so 20/8000 in this example)
The community health nurse (CHN) knows that a regular-sized blood pressure (BP) cuff will provide readings that are falsely high if used to measure BP in an obese person and will provide readings that are falsely low if used to measure BP in a small or very thin person. Which of the following does a regular-sized BP cuff lack when used to measure BP in all individuals?
a. Reliability
b. Sensitivity
c. Specificity
d. Validity
d. Validity
Which of the following is an example of primary prevention?
a. Papanicolaou (Pap) tests to detect cervical cancer
b. Screening of pregnant women for gestational diabetes
c. COVID-19 immunization clinics
d. Mammography to detect breast cancer
c. COVID-19 immunization clinics
