PHC 6001 Exam 1

Incidence rate =

# new cases / total person-time of observation

Standardized mortality ratio =

# observed deaths / # expected deaths

Core functions of public health

-Assessment -Policy development -Assurance

Modes of disease transmission

-Direct -Indirect

Two major indicators of public health

-Infant mortality -Life expectancy

The two ways that public health research differs from clinical research:

-PH focuses on disease prevention rather than disease treatment. -In PH, the units of concern are groups of people rather than individuals

The two measures of frequency are:

-Prevalence -Incidence

Tools of public health

-Surveillance systems -Implementation of research findings -Dissemination of guidelines -Development of effective public health interventions -Public policy

Epidemiologic tools are used to identify....

-frequency -distribution -determinants -control

Individual determinants of disease consist of:

-genetic makeup -gender -age -immunity level -diet -behaviors -existing diseases

Prevalence is affected by:

-number of new cases -duration of health-related state -rate of recovery and death

The two additive measures of association are:

-risk difference (RD) -incidence rate difference (IRD)

The four multiplicative measures of association:

-risk ratio (RR) -incidence rate ratio (IRR) -prevalence ratio (PR) -odds ratio (OR)

According to the book, the objectives of epidemiology are:

-to study the natural course of a disease from onset to resolution -to determine the extent of a disease in a population -to identify patterns and trends in disease occurrence -to identify the causes of disease -to evaluate the effectiveness of measures that prevent and treat disease

Prevalence values range from _____________.

0 to 1

The common sequence of etiology is...

1) clinical observations 2) Descriptive studies 3) Analytic studies

_____________ is the difference between absolute risk in placebo or standard therapy group and treatment group.

Absolute risk reduction (ARR)

______________ is the hypothetical event rate that would have occurred had the observed rates prevailed in a population with a distribution of that of the standard population.

Adjusted/standardized rate

_____________ test specific hypotheses with the goal of identifying causal links.

Analytic studies

____________ is the incidence proportion of becoming afflicted with a condition during an epidemic period.

Attack rate

Formula for the relationship between cumulative incidence and incidence rate

CI = IR x t t = time

_____________ is the number of deaths per number of cases of disease.

Case fatality rate

______________ is the proportion of people, among those who develop a disease, who then proceed to die from the disease.

Case fatality rate

________________ is the recognition of a new or increased pattern of morbidity or mortality.

Clinical observation

Definition of public health

Combination of sciences, skills, and beliefs directed to the maintenance and improvement of the health of all the people through collective or societal actions

___________ is the comparison of people to themselves in both the exposed and unexposed states with regard to a particular outcome.

Counterfactual ideal

___________ is the proportion of a fixed population experiencing a new event during a specified time period.

Cumulative incidence

______________ measures risk.

Cumulative incidence

_________ and ____________ are the two measures of incidence.

Cumulative incidence and incidence density

____________ describe new patterns in distribution and attributes of health-related states, and generates hypotheses about exposures and outcomes.

Descriptive studies

_________ is the usual or constant presence of a disease in a geographic area or population.

Endemic

__________ is occurrence in a population of an illness clearly in excess of normal expectancy

Epidemic

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

Epidemiology

______________ is the resistance of a group of people to an attack by a disease to which a large proportion of the members of the group are immune.

Herd immunity

___________ asks, How do you do it?

Implementation

________ is the number of new events occurring in a specified period in a defined population.

Incidence

___________ is most useful for evaluating the effectiveness of programs that try to prevent disease from occurring.

Incidence

____________ is useful to assess etiological association, and determining intervention/treatment efficacy/effectiveness.

Incidence

_____________ is also known as an incidence rate.

Incidence density

________________ is the number of new events in a specified period divided (most properly) by the accumulated person-time of observation.

Incidence density

_____________ is the absolute difference in the incidence density between the exposed and unexposed groups.

Incidence rate difference (IRD)

____________ is the ratio of the incidence density among the exposed to the incidence density among the unexposed.

Incidence rate ratio (IRR)

William Farr designed a classification system that was the precursor for the _____________________.

International Classification of Diseases (ICD)

___________ asks, What works?

Intervention and evaluation

__________ used an experimental study to to discover the cause and prevention of scurvy.

James Lind

___________ summarized the pattern of mortality in 17th-century London.

John Graunt

__________ showed that cholera was transmitted by fecal contamination of drinking water.

John Snow

___________ is the reciprocal of ARR

NNT

___________ is the number of persons needed to prevent one outcome.

Number needed to treat (NNT)

Underlying population and time period are critical to measures of ________.

Occurrence

________ is a ratio of the probability of an event occurrence to the probability of non-occurrence

Odds

____________ is the ratio of the odds of exposure among those with the outcome to the odds of exposure among those without the outcome.

Odds ratio (OR)

Formula for the relationship between incidence and prevalence:

P / (1 - P) = ID

What does each variable represent in P / (1 - P) = ID?

P = prevalence I = incidence D = mean duration of disease

Formula for population rate difference

PRD = Rt - Ru = RD x Pe Rt = rate for total pop'n Ru = rate for unexposed group RD = risk difference Pe = proportion of pop'n exposed

_________ is an epidemic which affects a large proportion of the population, usually involving several continents.

Pandemic

______________ is the number of cases of a disease or other outcome during a specified period of time, divided by (usually) the total specified population at the mid-point of the time period.

Period prevalence

________________ is the number of cases of the outcome of interest at a given time, divided by the total specified population at the time of outcome ascertainment.

Point prevalence

__________ is useful to describe population burden of a disease; set priorities for medical, public health policy interventions; and resource allocation.

Prevalence

The ____________ is the proportion of a specified population that is affected by the outcome of interest at a given time.

Prevalence proportion

_________ is the ratio of the prevalence among the exposed to the prevalence among the unexposed.

Prevalence ratio (PR)

_________ prevention is preventing the transfer of injury from occurring at all or at rates sustainable without causing damage to the body.

Primary

__________ is a ratio in which the numerator is included in the denominator

Proportion

_________ is a measure of the frequency of occurrence of a phenomenon in a defined population, expressed in change per unit time.

Rate

____________ is the % reduction in risk in the exposed group compared to the unexposed group.

Relative risk reduction (RRR)

___________ and _____________ conducted early research on smoking and lung cancer.

Richard Doll and A. Bradford Hill

__________ is the absolute difference in the incidence proportion between the exposed and unexposed groups.

Risk difference (RD)

____________ asks, What is the cause?

Risk factor evaluation

_______ is the ratio of the incidence proportion among the exposed to the incidence proportion among the unexposed.

Risk ratio (RR)

_________ prevention is mitigating the transfer of energy such that the amount of energy transferred causes less severe damage to the body.

Secondary

___________ asks, What is the problem?

Surveillance

____________ is the ongoing systematic collection, analysis, interpretation, and dissemination of outcome-specific data for use in the planning, implementation, and evaluation of public health practice.

Surveillance

_________ prevention is treating and rehabilitating injury to lessen long-term negative outcomes.

Tertiary

Goals of public health

To protect, promote, and restore the health of the population

_______________ pioneered a wide range of activities in the mid-19th century that are still being used by modern epidemiologists.

William Farr

Doll and Hill performed a _________ study to examine the relationship between smoking and lung cancer.

case-control

Population ____________ is individuals at a point in time.

cross-section

A person contributes time to the ___________ of an incidence rate only up until they are diagnosed with the disease of interest.

denominator

Population _____________ is individuals moving through time.

experience

Active surveillance

involves regular outreach to potential reporters

Crude rate =

number of events / population at risk

Passive surveillance

relies on others to choose to report

Etiology identifies __________.

the causes of health-related states