Module 3

Question 1

Disease

Answer 1

Any disruption in the function and structure of the body

An abnormal state in which the body is not capable of responding to or carrying on it’s normally required functions

Question 2

Morbidity

Answer 2

Any departure from a state of physiological and psychological well-being

Measured by incidence and prevalence
Described by ICD-9 and ICD-10 coding systems

Question 3

Natural history of disease

Answer 3

Normal course of disease from onset to resolution without treatment or intervention

Question 4

Epidemiologic surveillance

Answer 4

The ongoing systematic collection, analysis, and interpretation of health data essential to the planning implementation and evaluation of public health practice

Includes timely reporting of data to important agencies

Question 5

Applications of epidemiologic surveillance

Answer 5

1. Monitor changes in disease frequency
2. Monitor changes in levels of risk factors
   * *Commonly used for infectious diseases

Question 6

Reportable/notifiable diseases

Answer 6

Reporting mandated by federal and state statutes

Conditions deemed significant to public health
Ex: STDs, measles, foodborne illness, outbreaks, injuries

Question 7

Advantages of reportable disease data

Answer 7

Standardized case definitions
Availability of lab/clinical data
Comparability of data between jurisdictions

Question 8

Disadvantages of reportable disease data

Answer 8

Incompleteness of population coverage (ex: asymptomatic case)
Failure of physician to report
Unwillingness to report cases with social stigma

Question 9

Privacy Act of 1974

Answer 9

Prohibits release of confidential data without consent of individual

Question 10

Freedom of Information Act

Answer 10

Mandates release of government information to the public except personal and medical files

Question 11

HIPAA

Answer 11

Restricts access to protected health information

*PHI can be disclosed without patient authorization for public health purposes

Question 12

Sources of morbidity data

Answer 12

Disease reporting
Medical records
Insurance claims
Population-based morbidity surveys 
Absenteeism records

Question 13

Criteria for epidemiologic data

Answer 13

1. Nature (source)
2. Availability/access
3. Completeness of population coverage
4. Value and limitations

Question 14

Syndromic surveillance

Answer 14

Prospective surveillance of nonspecific health indicators (syndromes)

Use existing electronic health related data coded into nonspecific disease syndromes and analyzed in near real-time to monitor trends

Question 15

Objectives syndromic surveillance

Answer 15

To identify illness clusters early before diagnoses are confirmed and reported to public health agencies

To mobilize a rapid response thereby reducing morbidity and mortality

Question 16

Use of Syndromic surveillance by public health agencies

Answer 16

1. Situational awareness
2. Emergency response management
3. Outbreak recognition/characterization

Question 17

Traditional vs. Syndromic surveillance

Answer 17

Traditional: diagnosis-based
Syndromic: prediagnostic (helps with early detection)

*syndromic surveillance does not replace traditional public health surveillance

Question 18

Measures of disease frequency

Answer 18

1. Count
2. Ratio
3. Proportion
4. Rate

*Used to quantify health events in a population (morbidity, mortality)

Question 19

Count

Answer 19

The number of cases of a disease or other health phenomenon being studied (simplest most frequently performed quantitative measure)

*significant for rare diseases (Ebola)

Question 20

Ratio

Answer 20

Value obtained by dividing one quantity by another

*relationship between two numbers

No specified relationship between numerator and denominator

Question 21

Proportion

Answer 21

States a count relative to the size of the group

Ratio in which the numerator is part of the denominator

*can demonstrate the magnitude of the problem

Question 22

Rate

Answer 22

A ratio in which time forms part of the denominator

Includes:

• Disease frequency
• Unit size of population
• Time period during which an event occurs

Question 23

Incidence

Answer 23

The number of new cases of a disease that occur in a group during a certain time period

Useful for:

• research on the etiology of disease
• estimating risk of developing disease
• estimating effects of exposure to a factor of interest

Question 24

Prevalence

Answer 24

Number of existing cases of a disease in a population at some designated time

• indication of the extent of the problem
• estimating frequency of an exposure
• determining allocation of Heath resources such as facilities and personnel

Question 25

Relationship between Prevalence and incidence

Answer 25

Prevalence = Incidence x Duration

Question 26

Morbidity frequency measures

Answer 26

Incidence and prevalence

Question 27

Incidence rate

Answer 27

The rate of development of a disease in a group over a certain time period

(New cases/population at risk) during time period

Question 28

Incidence density

Answer 28

Used when members of a population or study group are under observation for different lengths of time

Number of new cases during time period/total person-time of observation

Question 29

Attack rate

Answer 29

Alternative form of incidence used for diseases observed any population for short time period

*not a true rate because time dimension is often uncertain

Question 30

Point prevalence

Answer 30

(Number of people ill/total number in the group) at a point in time

Question 31

Period Prevalence

Answer 31

(Number of persons ill/average population) during a time period

Question 32

Crude rates

Answer 32

Nonspecific rates

*Differences crude rates may be the result of systematic factors within the population rather than true variation in rates; use with caution when comparing between populations

Question 33

Specific rates

Answer 33

Refer to a particular subgroup of the population

Can be defined in terms of race, age, sex, or single cause of death or illness