Quiz 4

Question 1

Public Health Surveillance

Where does the word surveillance come from?

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Answer 1

french!

sur (over)

veiller (to watch)

Question 2

Public Health Surveillance

What is the definition of surveillance?

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Answer 2

close and continuous observation of one or more persons for the purpose of direction, supervision, or control

Question 3

Public Health Surveillance

What is active surveillance?

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Answer 3

epidemiologist initiated (health department initiated)

Question 4

Public Health Surveillance

What is passive surveillance?

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Answer 4

physician initiated (health provider initiated)

Question 5

Public Health Surveillance

What do you do when conducting surveillance?

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Answer 5

1. identify, define, and measure the health problem of interest
2. collect and compile data about the problem
3. analyze and interpret these results
4. provide data and interpretation to those responsible for controlling the health problem
5. monitor and periodically evaluate the usefulness and quality of surveillance to improve it for future use

Question 6

Public Health Surveillance

What are the characteristics of surveillance?

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Answer 6

• timeliness: to implement effective control measure
• representation: provide an accurate picture of the temporal trend of the disease
• sensitivity: indentification of individuals with disease
• specificity: exclude those without the disease

Question 7

Public Health Surveillance

What questions should be considered when selecting a health problem for surveillance?

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Answer 7

• What factors might prompt an investigation into a disease?
• Why would we prioritize one disease over another?
• What characteristics of a disease would warrant action?

Question 8

Public Health Surveillance

What factors are included when selecting a health problem for surveillance?

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Answer 8

• incidence and prevalence
• severity
• mortality caused by the problem
• socioeconomic impact
• communicability
• potential for an outbreak
• public perception and concern
• international requirements
• preventability, control measures and treatment
• capacity of the health system to implement control measures

Question 9

Public Health Surveillance

How can you define the health problem?

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Answer 9

by utilizing the case definition for surveillance

Question 10

Public Health Surveillance

What does the term constellation of signs refer to in disease surveillance?

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Answer 10

situations where a disease is identified based on a group of signs, symptoms, chief complaints, or presumptive diagnoses—rather than specific clinical or lab diagnostic criteria.

ALSO KNOWN AS SYNDROMIC SURVEILLANCE

Question 11

Public Health Surveillance

What is the goal of syndromic surveillance?

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Answer 11

to provide an earlier indication of an unusual increase in illness

to facilitate early intervention

Question 12

Public Health Surveillance

Does syndromic surveillance rely on a clinician testing or thinking of a specific disease?

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Answer 12

NO

it is less specific and focuses on syndromes instead of diagnoses

Question 13

Public Health Surveillance

Once a disease is identified, what data sources must be identified for surveillance?

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Answer 13

• individual persons
• health care providers, facilities and records
• environmental conditions
• administrative actions
• financial transactions (ex: sales of cigs)
• legal actions
• laws and regulations

Question 14

Public Health Surveillance

What methods can be used to collect majority of health-related data?

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Answer 14

• surveys
• notifications
• registries
• reanalysis

Question 15

Public Health Surveillance

Define survey

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Answer 15

an investigation that uses a “structured and systematic gather of information” from a sample of “a population of interest to describe the population in quantiative terms”

• most common method for gathering information about populations
• can be conducted once or on a periodic basis

Question 16

Public Health Surveillance

What must a survey entail?

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Answer 16

• representative sample –> so results can be generalized to the entire population

Question 17

Public Health Surveillance

Define notification

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Answer 17

the reporting of certain diseases or other health related conditions by a specific group, as specified by law, regulation, or agreement

Question 18

Public Health Surveillance

What does a notification entail?

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Answer 18

• typically made to the state or local health agency
• when required by law, the diseases are known as notifiable
• initiated by passive surveillance –> providers send reports to a health department

Question 19

Public Health Surveillance

Define registry

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Answer 19

method for documenting or tracking events or persons over time

they are specifc compared to notifications
because they are intended to be a permanent record of persons or events

Question 20

Public Health Surveillance

What does a disease registry entail?

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Answer 20

tracks a person with disease over time and usually includes:
- diagnostic
- treatments
- outcome information

Question 21

Public Health Surveillance

Define reanalysis / secondary use of data

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Answer 21

surveillance for a health problem can use data originally collected for other purposes

Question 22

Public Health Surveillance

What are some things to keep in mind with reanalysis?

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Answer 22

can lack timeliness or sufficient detail pertinent to current outbreak

however:
primary collection of data is time-consuming and resource-intensive so this may be beneficial when the health problem is of high priority if there are no adequate sources of data

Question 23

Displaying Public Health Data

What is a table?

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Answer 23

a set of data arranged in rows and columns

Question 24

Displaying Public Health Data

Why are tables used?

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Answer 24

serve as the basis for preparing additional visual displays of data

simplistic version of recording raw data

Question 25

# Displaying Public Health Data What is a **contingency table**? ## Footnote lecture 10

Answer 25

a table that consists of two variables and each of those variables have two categories

Question 26

# Displaying Public Health Data What are **composite** **tables**? ## Footnote lecture 10

Answer 26

several tables that are combined into one for space conservation on a report **these tables *do NOT* indicate interrelationship between the variables displayed**

Question 27

# Displaying Public Health Data What are **table** **shells**? ## Footnote lecture 10

Answer 27

epidemiologists may ***anticipate*** and design their analyses in advance to prepare for data collection and expedite data analysis **table can be modified after data collection**

Question 28

# Displaying Public Health Data How can table shells be used? ## Footnote lecture 10

Answer 28

to help prepare and makes the data analysis quicker ***very important during the planning phase of a study***

Question 29

# Displaying Public Health Data What are **class intervals** and what are they used for? ## Footnote lecture 10

Answer 29

when some variables have broad range of possibility, thus class intervals are created example: - 0 drinks / week - 1-3 drinks / week - 4-7 drinks / week - greather than 8 drinks / week

Question 30

# Displaying Public Health Data What must class intervals entail? ## Footnote lecture 10

Answer 30

must be: - mutually **exclusive** (each individual falls into one interval) - **exhaustive** (ALL individuals can fit into a class interval; some surverys have an option for "other") - must have a natural baseline to include those who **have not** had an exposure (example: for non smokers = 0 cigarettes per day)

Question 31

# Displaying Public Health Data Define graphs / what do they do? ## Footnote lecture 10

Answer 31

**display numeric data in visual form** - clearly indentify variables portrayed with legends or keys - ensure scales for each axis are appropriate for data presented **x-axis = independent variable** **y-axis = dependent variable**

Question 32

# Displaying Public Health Data arithmetic-scale line graph ## Footnote lecture 10

Answer 32

**why use them:** to show patterns or trends over some variable (often time) **when to use:** need to show long series of data (ex: rates over time)

Question 33

# Displaying Public Health Data semilogarithmic-scale line graph ## Footnote lecture 10

Answer 33

**why use them:** when the data set is so large **when to use:** proper construction of an arithmetic-scale graph is problematic

Question 34

# Displaying Public Health Data histograms ## Footnote lecture 10

Answer 34

**why use them:** to graph the frequency distribution of a continuous variable

Question 35

# Displaying Public Health Data population pyramid ## Footnote lecture 10

Answer 35

**when to use / why use:** display the count or percentage of a *population* by age and sex

Question 36

# Displaying Public Health Data frequency polygon ## Footnote lecture 10

Answer 36

**when to use / why use:** to graph a frequency distribution - *numbers of observations in an interval is marked with a single point and each point is connected with a straight line*

Question 37

# Displaying Public Health Data survival curves ## Footnote lecture 10

Answer 37

**when to use / why use:** display the proportion of one or more groups that are ***still alive at different time periods***

Question 38

# Displaying Public Health Data scatter diagrams ## Footnote lecture 10

Answer 38

**when to use / why use:** to portray the relationship between two variables - *a point is placed on the graph where the two variables intersect*

Question 39

# Displaying Public Health Data grouped bar charts ## Footnote lecture 10

Answer 39

**when to use / why use:** to illustrate data from two or three variable tables - *bars should be illustrated distinctively and described in a legend*

Question 40

# Displaying Public Health Data stacked bar charts ## Footnote lecture 10

Answer 40

groups are differentiated **within a single bar** cons: - less effective at displaying the relative size of the subgroups

Question 41

# Displaying Public Health Data 100% component bar charts ## Footnote lecture 10

Answer 41

a variant of a stacked bar chart *BUT* **all bars are pulled to the same height** and the components are show as % (percentages, not actual values)

Question 42

# Displaying Public Health Data deviation bar charts ## Footnote lecture 10

Answer 42

**when to use / why use:** to **display both positive and negative changes from a baseline**

Question 43

# Displaying Public Health Data pie charts ## Footnote lecture 10

Answer 43

size of the "slices" show the proportional contribution of each component part

Question 44

# Displaying Public Health Data dot plots ## Footnote lecture 10

Answer 44

**when to use / why use:** use dots to **show the relationship between a *categorical* and *continuous* variable**

Question 45

# Displaying Public Health Data phylogenetic tree ## Footnote lecture 10

Answer 45

branching chart that indicates **the evolutionary lineage or genetic relatedness of organisms** - *distance on the tree reflects genetic differences*

Question 46

# Displaying Public Health Data decision trees ## Footnote lecture 10

Answer 46

branching chart that represents the **logical pathway of a public health decision** *building blocks:* - decisions - outcomes - probabilities

Question 47

# Displaying Public Health Data maps ## Footnote lecture 10

Answer 47

**when to use / why use:** to show geographic location of events or attributes