HHSC midterm 1

What is Occam's razor?

The simplest explanation is most likely the right one.

What are some misconceptions debunked regarding medical conspiracies?

Cellular 5G technology does not cause COVID-19, masks reduce the spread of COVID-19, water fluoridation is safe, HIV treatments do not cause AIDS, and pharmaceutical companies are not hiding the cure for cancer.

What is a common trait among people who believe in medical conspiracies?

They are more likely to believe in other medical conspiracies and share similar characteristics with people who distrust vaccines.

How do we counter anti-vaccination movements?

Provide information regarding vaccine-preventable diseases, establish strong patient-provider relationships, encourage dialogue, and build trust.

What are common beliefs of people who support the anti-vaccination movement?

They tend to believe in other conspiracies, feel their personal freedoms are being threatened, and may be disgusted by or fearful of needles, hospitals, or blood.

Who believes in the anti-vaccination movement?

There is no correlation between supporting the anti-vaccination movement and income, education, gender, or age.

Do vaccines cause autism?

No, vaccines do not cause autism.

What is the impact of anti-vaccination movements on social media?

Anti-vaccination movements expanded over social media, spreading misinformation regarding vaccine safety.

What happened to Andrew Wakefield's fraudulent article?

The Lancet retracted the article in 2010, and Wakefield lost his license to practice medicine in the UK.

Who published fraudulent findings linking MMR vaccine to autism?

Andrew Wakefield.

What is the misconception about vaccines and autism?

The misconception is that vaccines cause autism, which has been debunked by multiple studies.

What is the controversy surrounding the HPV vaccine?

There is controversy about the new HPV vaccine regarding its necessity and safety.

What is the herd immunity threshold for measles?

83-94%.

What is the herd immunity threshold for pertussis?

92-94%.

What is the herd immunity threshold for rubella?

83-85%.

What is the herd immunity threshold for smallpox?

80-85%.

What is the herd immunity threshold for polio?

80-86%.

What is the herd immunity threshold for mumps?

75-86%.

What is herd immunity?

Once enough individuals receive the vaccine (the herd immunity threshold), the population is considered to have herd immunity for that pathogen.

What are the benefits of vaccination for populations?

As more individuals receive the vaccine, the chance that unvaccinated individuals are exposed to the pathogen is reduced.

What diseases might we be able to eradicate with vaccines in the future?

Measles, diphtheria, tetanus, yellow fever, and whooping cough.

Which disease is close to being eradicated by vaccines?

Polio.

What is the first and only disease eradicated by vaccines?

Smallpox.

What does the Latin word "vacca" mean?

It means "cow".

What is the historical significance of the cowpox virus in vaccination?

In 1796, the cowpox virus was successfully used to inoculate against the smallpox virus.

What happens when the body is exposed to the infectious form of the pathogen after vaccination?

The body is much more likely to eliminate the pathogen before it causes disease.

What is the purpose of vaccination?

Administering a non-infectious form of the virus or bacteria to build the body's natural immune response against the pathogen.

Why is peer review important in systematic reviews?

Peer review ensures that the methodology and findings of a systematic review are rigorous and credible.

What is a potential issue with the labeling of systematic reviews?

Sometimes authors label their work as a "systematic review" when it is actually a narrative review or lacks proper methodology.

What can cause disagreement in systematic reviews and meta-analyses?

Disagreement can occur when studies with different populations are pooled together, raising questions about the validity of combining results.

What is the biggest weakness of systematic reviews and meta-analyses?

They are only as reliable as the studies they include; bad studies can lead to inaccurate conclusions.

How do systematic reviews and meta-analyses address publication bias?

They are effective at identifying and sometimes correcting biases where positive studies are more likely to be published than negative ones.

What is a major strength of systematic reviews and meta-analyses in healthcare?

They provide a more efficient way to gather evidence, often directly applicable to medical and healthcare practice.

What are the benefits of systematic reviews and meta-analyses?

They save time, provide a reliable synthesis of evidence, and are essential for evidence-based medicine, as they are more applicable to health practice than individual studies.

What is the benefit of meta-analysis in systematic reviews?

It enhances systematic reviews by providing a statistical summary, allowing for a clearer understanding of the overall effect.

How does a meta-analysis work?

Meta-analyses plot results from reviewed studies on a chart and use statistical methods to synthesize the findings into a single result.

What is a meta-analysis?

A meta-analysis is a statistical method often used after conducting a systematic review to combine results from different studies and generate a new result.

How do systematic reviews help understand relationships between exposures and outcomes?

They account for differences in population, treatments, settings, and methods to evaluate the strength of evidence across studies.

How does a systematic review differ from a narrative review?

Unlike narrative reviews, systematic reviews are more structured, with explicit methods and protocols, and they assess study quality.

What is the goal of a systematic review?

The goal is to limit bias in identifying, evaluating, and synthesizing the literature, providing a more reliable conclusion.

How does a systematic review assess the quality of studies?

Systematic reviews use protocols to determine how literature searches are conducted and how the quality of studies is assessed.

What are the strengths of a systematic review?

Systematic reviews minimize bias, use objective analysis, and assess the magnitude of effects, providing a reliable synthesis of research.

What is a systematic review?

A systematic review is a scientific approach to summarizing research literature with well-defined research questions and explicit, replicable methods.

What is the difference between multiple narrative reviews on the same topic?

Different narrative reviews can come to different conclusions about the same topic, as they may not follow a consistent methodology.

What is the "vote tally" system in narrative reviews?

It involves counting the number of studies reporting positive or negative effects without considering how strong those effects were.

What are the strengths of a narrative review?

Narrative reviews provide a broad overview of a topic but may not critically assess the quality of studies or consider the magnitude of effects.

What is a narrative review?

A narrative review is an expert's opinion on a topic, summarizing various studies without a refined research question or transparent literature search methods.

What is the difference between infection and disease?

Infection is the invasion of the body by pathogens; disease occurs when the infection impairs the body's functions.

What is an asymptomatic carrier?

An asymptomatic carrier is a person who is infected by a pathogen but does not show symptoms of the disease.

What is the case fatality rate (CFR)?

CFR refers to the percentage of people who die from a particular disease.

What is the difference between cold and flu onset?

Cold onset is gradual, while flu onset is abrupt with more severe symptoms.

What are the key symptoms of a cold?

Cold symptoms generally include a sore throat, runny nose, and gradual onset without a fever.

What are the key symptoms of the flu?

Flu symptoms typically include fever, chills, fatigue, muscle aches, and abrupt onset.

What is R0?

R0 (basic reproduction number) is a measure of how many people one infected person is likely to infect.

What is contagiousness?

Contagiousness refers to how easily a pathogen spreads from person to person.

What is pathogenicity?

Pathogenicity refers to the ability of a pathogen to cause disease.

What is vertical transmission?

Vertical transmission occurs when pathogens are passed from parent to child during pregnancy or birth (e.g., HIV).

What is indirect transmission?

Indirect transmission happens when the pathogen is spread through contaminated surfaces, air, or water (e.g., touching a doorknob after an infected person has touched it).

What is direct transmission?

Direct transmission occurs when the host comes into direct contact with the pathogen (e.g., eating contaminated food or being bitten by an infected animal).

What are examples of intestinal worms that are pathogens?

Examples include Ascaris, Trichuris trichiura, and Ancylostoma.

What are protozoa pathogens?

Protozoa pathogens include Entamoeba histolytica, Giardia, and Plasmodium (malaria).

What are common fungi pathogens?

Examples of fungi pathogens include Candida albicans, Aspergillus, and Cryptococcus neoformans.

What is the difference between true pathogens and opportunistic pathogens?

True pathogens infect any susceptible host, while opportunistic pathogens infect only those with weakened immune systems.

What are examples of gram-negative bacilli bacteria?

Examples of gram-negative bacilli include Salmonella, Shigella, and Pseudomonas.

What are examples of gram-positive bacilli bacteria?

Examples of gram-positive bacilli include Corynebacteria and Bacillus anthracis.

What are gram-negative cocci bacteria?

Examples of gram-negative cocci include Neisseria gonorrhoeae and Neisseria meningitidis.

What are gram-positive cocci bacteria?

Examples of gram-positive cocci include Staphylococcus aureus and Streptococcus pneumoniae.

What are RNA viruses?

RNA viruses include influenza viruses (flu), coronaviruses (SARS), and retroviruses (HIV).

What are DNA viruses?

DNA viruses include adenoviruses (common cold), herpesviruses (chickenpox), and poxviruses (smallpox).

What are opportunistic pathogens?

Opportunistic pathogens cause infection primarily in hosts with weakened immune systems, such as the elderly, young children, and those with HIV or undergoing chemotherapy.

What are true pathogens?

True pathogens can infect any susceptible host and cause disease.

What is a host?

A host is the person who makes contact with a pathogen and becomes infected.

What are infectious diseases?

Infectious diseases occur when a person makes contact with pathogens (agents that cause diseases), such as bacteria, viruses, fungi, and parasites.

What is the importance of test results in diagnosing diseases?

Just because a test indicates you have a disease does not guarantee you have it. Likewise, just because it says you don't have the disease does not mean you are disease-free. The test's accuracy depends on how well it reduces false positives and false negatives.

What is the trade-off between false positives and false negatives?

Tests have a balance between false positives (incorrectly indicating a disease) and false negatives (incorrectly indicating no disease). The trade-off depends on the importance of the test's accuracy in a given context.

What are the four types of test results?

1. True Positives: The test correctly identifies a disease. 2. False Positives: The test incorrectly identifies a disease. 3. True Negatives: The test correctly indicates no disease. 4. False Negatives: The test incorrectly indicates no disease.

What are the potential issues with risk headlines in the media?

Headlines can be misleading. For example, saying "Exposure Y doubles your risk of Disease X!" could be true but might only mean a small absolute increase in risk.

What is an example of how to calculate relative and absolute risk?

If 1 per 1000 people without exposure gets Disease X, and 2 per 1000 with exposure get it: - Absolute risk increase = 0.2% - 0.1% = 0.1%. - Relative risk = 0.2% / 0.1% = 2.0, indicating a 100% increase in risk.

What is the relationship between absolute and relative risk?

Absolute risk measures the actual difference in risk between exposed and unexposed groups, while relative risk measures the proportional change in risk between these groups.

What is absolute risk?

Absolute risk is the actual risk of an outcome happening in a group. It is calculated by subtracting the baseline risk from the risk after exposure.

What is relative risk?

Relative risk is the proportional increase or decrease in risk between an exposed group and a control group. It is calculated by comparing the risk in the exposed group to the risk in the unexposed group.

What are meta-analyses and systematic reviews?

Meta-analyses and systematic reviews combine data from multiple studies to provide the strongest evidence, helping to summarize and clarify the findings of many individual studies.

What are randomized controlled trials (RCTs)?

RCTs are studies where participants are randomly assigned to a treatment group or a control group. RCTs are considered one of the best forms of evidence for causation.

What are case-control studies?

Case-control studies compare individuals with a disease (cases) to those without the disease (controls) to see if exposure to a factor is more common in one group. They are less definitive than cohort studies but provide useful evidence.

What are cohort studies?

Cohort studies follow a group of people over time to see if they develop a disease based on exposure to a certain factor. They provide stronger evidence for causation but are costly and time-consuming.

What is the problem with confusing correlation with causation?

Correlation does not imply causation. There could be third factors at play, and the relationship between the two factors might not be causal.

Why can't cross-sectional studies prove causation?

Because they can only show correlations, cross-sectional studies cannot demonstrate that one factor causes another; they only show that two factors are related.

What are cross-sectional studies?

Cross-sectional studies observe people at a single point in time. They can identify correlations between exposures and diseases but cannot prove causation.

What is the issue with animal and in vitro studies?

Animal and in vitro studies provide foundational knowledge but cannot be directly applied to humans because what is true in animals may not be true in human models.

Why are case reports considered weak evidence?

Case reports and opinions are considered weak because they involve small sample sizes (sometimes only one person) and may not be easily replicated.

What is the difference between correlation and causation?

Correlation: A statistical association between two factors. It does not imply that one factor causes the other. Causation: One factor leads to the occurrence of the other. Exposure to one factor may directly create the outcome.

What is risk?

Risk refers to the likelihood or chance of something bad happening. It doesn't guarantee that something negative will definitely occur, but it indicates the probability of an event happening.

What are some issues in scientific research?

Funding competition: Researchers compete for limited financial resources. Poor study designs: Can lead to incorrect conclusions. Replication studies: Often underappreciated but necessary for confirming results. Peer review issues: Bad studies may pass through peer review. Poor communication of science: Misinformation may spread without proper context.

What was the 2013-2016 West African Ebola outbreak?

Ebola in West Africa killed 11,310 people, with the virus traced back to a 2-year-old boy in Guinea. Epidemiologists tracked the spread and worked to contain the disease through surveillance and quarantine.

What is the significance of the 2003 Toronto SARS outbreak in epidemiology?

Epidemiologists tracked the spread of SARS, identified the index case, and contained the outbreak through quarantine measures, demonstrating the importance of field epidemiology in disease control.

What was the Framingham Heart Study?

The Framingham Heart Study, started in 1948, identified major cardiovascular disease risk factors, such as smoking, obesity, and high cholesterol, and is ongoing with four generations of participants.

What was John Snow's contribution to epidemiology?

John Snow mapped cholera cases in London and identified the contaminated Broad Street pump as the source, laying the foundation for the study of waterborne diseases.

What was Ignaz Semmelweis' contribution to epidemiology?

Semmelweis discovered that handwashing reduced puerperal fever (childbed fever) mortality after childbirth, leading to improved sanitation practices in hospitals.

What are the objectives of epidemiology?

1. Identify the etiology and risk factors of diseases. 2. Determine the extent of disease in a community. 3. Study the natural history and prognosis of diseases. 4. Evaluate preventative and therapeutic measures. 5. Provide the foundation for public policy development.

What is epidemiology?

Epidemiology is the study of the distribution and determinants of health-related states or events, and the application of this study to control diseases and other health problems.