HEALTH 261 Exam 1 Study Guide Flashcards

A comprehensive set of 40 practice flashcards in question-and-answer format for HEALTH 261 Exam 1, covering epidemiology history, measures of disease occurrence, data sources, and descriptive epidemiology.

What is the official definition of epidemiology?

Epidemiology is the study of the distribution and determinants of health-related states or events in specified populations, and the application of that study to control health problems.

What was Hippocrates' primary contribution to epidemiology?

He connected disease to environmental and lifestyle factors rather than supernatural causes.

What was John Graunt's contribution to early epidemiology?

He used mortality data/statistics, studied births and deaths, and contributed to early quantitative epidemiology.

What primary public health contribution is associated with Edward Jenner?

He developed the smallpox vaccination approach.

How did John Snow investigate cholera, and what source did he identify?

He investigated cholera by tracing an outbreak to contaminated water during his famous Broad Street pump investigation.

What was William Farr's major contribution to epidemiology?

He developed and advanced vital statistics and mortality statistics.

What were Robert Koch's major contributions to public health and epidemiology?

He made major contributions to germ theory and the identification of disease-causing organisms.

What importance did Ignaz Semmelweis demonstrate in disease prevention?

He demonstrated the importance of handwashing in preventing childbed fever.

How did Florence Nightingale advance healthcare and sanitation?

She used statistics and data visualization to improve healthcare and sanitation.

What key medical discovery is attributed to Alexander Fleming?

He discovered penicillin.

What is the main distinction between morbidity and mortality?

Morbidity refers to illness or disease, whereas mortality refers to death.

How are endemic, epidemic, and pandemic diseases distinguished?

Endemic is the constant expected presence of a disease; epidemic is an occurrence greater than expected; pandemic is an epidemic spreading across large geographic areas involving multiple countries or continents.

In epidemiology, what is the difference between distribution and determinants?

Distribution describes who gets the disease, where, and when; determinants explain why and how it occurs by identifying influencing factors.

How do descriptive epidemiology and analytic epidemiology differ?

Descriptive epidemiology describes disease patterns by Person, Place, and Time (what is happening); analytic epidemiology evaluates Exposure to Outcome relationships (why or how it is happening).

What are the three levels of prevention in public health?

Primary prevention prevents disease before it occurs; secondary prevention detects disease early through screening; tertiary prevention reduces complications or disability after disease has occurred.

What distinguishes a count, a proportion, and a rate?

A count is simply the total number of events; a proportion represents a fraction of a population (part divided by whole); a rate incorporates a specific time component to measure frequency.

How is a ratio defined in epidemiologic terms?

A ratio compares two quantities ($\frac{A}{B}$), where the numerator does not necessarily have to be included in the denominator.

Which type of graph is best suited for demonstrating disease trends over time?

A line graph.

What is the visual difference between a bar graph and a histogram?

In a bar graph, bars compare separate categories and do not touch; in a histogram, bars display continuous numerical intervals and touch each other.

What does incidence measure, and what is its basic formula?

Incidence measures NEW cases in a population at risk over a specified period. Formula: $\text{Incidence} = \frac{\text{New cases during period}}{\text{Population at risk during period}} \times k$

What does prevalence measure in a population?

Prevalence measures ALL existing cases (both old and new) at a specific point or period of time.

What is the difference between point prevalence and period prevalence?

Point prevalence measures disease presence at one specific point in time; period prevalence measures individuals who had the disease at any time during a specified time frame.

What is an attack rate and when is it primarily used?

An attack rate is a form of incidence used during an outbreak, calculated as $\text{Attack rate} = \frac{\text{New cases during outbreak}}{\text{Population exposed}} \times 100$.

How is the Case Fatality Rate (CFR) calculated?

$$\text{CFR} = \frac{\text{Deaths from disease}}{\text{People with disease}} \times 100$$

What does proportional mortality express?

It expresses the percentage of total deaths in a population caused by a specific disease: $\text{Proportional mortality} = \frac{\text{Deaths from specific cause}}{\text{Total deaths}} \times 100$.

Why is the U.S. Census essential for epidemiologic calculations?

It provides accurate population counts and demographic information needed as denominators for calculating health rates.

What are examples of vital events tracked by vital registration systems?

Live births, deaths, and fetal deaths.

What is the definition of public health surveillance?

The ongoing, systematic collection, analysis, interpretation, and dissemination of health data for public health action.

What is the main purpose of syndromic surveillance?

To identify potential disease outbreaks early by analyzing symptom patterns before confirmed medical diagnoses are available.

Why do reportable disease surveillance systems suffer from underreporting?

Because not every infected person seeks medical care, gets tested, gets diagnosed, or gets properly reported by healthcare providers.

What is the primary focus of the Behavioral Risk Factor Surveillance System (BRFSS)?

Collecting data on health-related behaviors and risk factors such as smoking, physical activity, and alcohol use.

What population and variables does the YRBSS monitor?

It monitors youth and student populations, focusing on risk behaviors related to injury, substance use, sexual behavior, physical activity, and nutrition.

How does the National Health Interview Survey (NHIS) gather data?

It collects health status, conditions, and healthcare utilization information through personal household interviews.

How does NHANES differ from survey-only data collection systems?

NHANES combines health interviews with physical examinations, direct measurements, and laboratory tests.

What is the function of a disease or case registry?

To collect comprehensive ongoing information about individuals diagnosed with a specific condition (e.g., cancer) to study disease patterns, treatments, and outcomes.

What three core variables frame descriptive epidemiology?

Person (Who?), Place (Where?), and Time (When?).

How do secular trends and seasonal trends differ?

A secular trend represents long-term changes over many years or decades, while a seasonal trend reflects predictable changes matching seasons of the year.

If $250$ out of $5{,}000$ students develop influenza during a semester, what is the incidence per $1{,}000$ students?

$\frac{250}{5000} = 0.05$; $0.05 \times 1000 = 50$ new cases per $1{,}000$ students.

If $5$ patients die out of $200$ diagnosed cases of a disease, what is the Case Fatality Rate?

$$\frac{5}{200} \times 100 = 2.5\%$$

If $20$ out of $80$ attendees at a banquet become ill, what is the attack rate?

$$\frac{20}{80} \times 100 = 25\%$$

Explain the prevalence pool

Cases enter the through incidence and leaves as recovery or death

Increase Prevalence

Increase disease duration

Decrease disease severity

Increase in new cases

Decrease Prevelance

Decrease in duration

Increase disease severity

Decrease in new cases

Proportional Mortality Rate (PMR%)

Mortality due to specific cause during a time period/ Mortality due to all causes during the same time period, multiplied by 100.

Cause specific Mortality Rates

Mortality cause/ population size multiplied by 100

Age Specific Mortality Rate (R)

(R)= Number of deaths among (specific) age/ number of people who are (specific age)

Demographic Characteristics

Race

Age

Sex