SCREENING AND PUBLIC HEALTH SURVEILLANCE

Question 1

Presumptive identification of an unrecognized disease or defect by the application of tests, examinations or other procedures that can be applied rapidly
Mainly used to identify ASYMPTOMATIC INDIVIDUALS at an earlier stage in the natural history of diseases

Answer 1

Screening

Assumption: Earlier diagnosis leads to earlier treatment that will improve diseases prognosis

Question 2

Screening test vs. Diagnostic test:
Asymptomatic individuals
Less accurate
Less expensive
Not a basis for treatment: not meant to be diagnostic
Sort out apparently well individuals who probably have a disease from those who probably not

Answer 2

Screening

Question 3

Screening test vs. Diagnostic test:
Symptomatic individuals 
More accurate
More expensive
Basis for treatment

Answer 3

Diagnostic Test

Question 4

Characteristics of a Disease Appropriate for Screening:

Given the high cost and possible adverse consequences of screening it is only justifiable to screen for major diseases

Answer 4

Disease is serious with severe consequences

Question 5

Characteristics of a Disease Appropriate for Screening:
Screening is carried out in the premise that the natural history of the disease can be altered by earlier treatment
Ex: breast cancer is better with screening vs pancreatic cancer

Answer 5

Treatment is more effective at an earlier stage

Question 6

Characteristics of a Disease Appropriate for Screening:
Screening test is designed to identify initial biologic abnormalities so that the affected individual comes to medical attention earlier

Answer 6

Disease has a clinical detectable preclinical stage

Question 7

Characteristics of a Disease Appropriate for Screening:

It is not efficient or cost effective to screen for rare or acute diseases

Answer 7

The preclinical phase is fairly LONG and prevalent in the target population

Question 8

ODD MAN OUT:
Characteristics of a Screening Test

1. Economical or cost effective: expense of the test must be considered relative to the benefit of the early diseases detection
2. Convenient: simple and can be done rapidly
   Relatively free of risk and discomfort
3. Acceptable to a large number of individuals: participation is voluntary
4. Highly valid and reliable: ability of test gives the consistent results
5. Large amount of human resource required

Answer 8

5. Large amount of human resource required

Question 9

Evaluation of Screening Programs:

Screening programs should be conducted efficiently, with minimal inconvenience and discomfort and reasonable cost

Answer 9

Feasibility

Question 10

Evaluation of Screening Programs:

Screening programs should achieve its goal of reducing morbidity and mortality

Answer 10

Effectiveness

Question 11

TRUE OR FALSE:

Effectiveness of a Screening Program:
Customary way: comparison of the survival experience of a screened population with that of an unscreened population

Answer 11

TRUE

Question 12

Potential Systematic Errors:

occurs when individuals who volunteer for a study differ in relevant clinical characteristics from those who do not

Answer 12

Volunteer bias

Question 13

Potential Systematic Errors:

Phenomenon where early diagnosis of a disease falsely makes it look like people are surviving longer

Answer 13

Lead-time bias
Lead time: interval between the time of disease detection
Through screening and the time of disease recognition in the absence of screening

Question 14

Potential Systematic Errors:
Phenomenon whereby slower-growing, less aggressive tumors have a longer preclinical screen-detectable period
Are therefore more likely to be screen-detected than faster-growing, more aggressive cancers

Answer 14

Length time bias

Question 15

Types of Screening:
____: general population; Newborn screening
____: high-risk groups; Mammography and pap smear
____: case-finding; Aimed at patients who consult a health practitioner for some other purpose
____: several screening tools to detect several conditions at the same time; Detecting STDs

Answer 15

Mass screening
Targeted screening
Opportunistic screening
Multiphasic screening

Question 16

Multiple Screening tests:
those who are positive on the first test will be subjected to the second test
Aka serial testing
Test increases overall specificity

Answer 16

Sequential

Question 17

Multiple Screening tests:
participants are subjected to two or more tests at the same time
Aka parallel testing
Test that increases overall sensitivity

Answer 17

Simultaneous

Question 18

French: “sur” (over) + “veiller” (to watch)
A systematic collection, collation, and analysis of data, and the prompt dissemination of the resulting information to those who need to know so that action can result
Continuing scrutiny of all aspects of the occurrence and the spread of a disease that are pertinent for effective control

Answer 18

Public Health Surveillance

Provides and interprets data to facilitate the prevention and control of disease
Most important purpose of public health surveillance
Should always have clear objectives
Includes clear description of how data will be used to prevent or control the disease

Question 19

TRUE OR FALSE:
Information Loop of Public Health Surveillance:

Starts from the collection in the public and then collation, analysis and interpretation in the health agencies and lastly the dissemination and utilization of the public

Answer 19

TRUE

Question 20

ODD MAN OUT:
Objective of Public Health Surveillance

1. Detect epidemics
2. Reveal hidden public health data
3. Monitor intervention program
4. Monitor impact of policy change
5. Monitor health system

Answer 20

2. Reveal hidden public health data

Question 21

ODD MAN OUT:
Actions in Public Health Surveillance

1. Office expansion
2. Epidemic response
3. Program monitoring
4. Health policy
5. Resource allocation

Answer 21

1. Office expansion

Question 22

ODD MAN OUT:
Data in Public Health Surveillance

1. Early warning information
2. Program indicators
3. Top-secret data
4. Health indicators
5. Administrative data

Answer 22

3. Top-secret data

Question 23

ODD MAN OUT:
System in Public Health Surveillance

1. One-way information exchange
2. Active surveillance
3. Health information
4. Health information and management

Answer 23

1. One-way information exchange

Question 24

Unit of Surveillance:

detection of epidemics, newly emerging health problems or changes in health practices

Answer 24

Immediate detection

Question 25

Unit of Surveillance: | estimating the magnitude of a health problem (cost, assessing control activities, and setting research priority)

Answer 25

Periodic Dissemination

Question 26

Unit of Surveillance: describing the natural history of disease, facilitating epidemiologic in laboratory research, and documenting distribution and spread of disease and inquiry

Answer 26

Stored information

Question 27

ODD MAN OUT: Characteristics of a well-conducted Public Health Surveillance System: ``` Acceptability Flexibility Cheapness Validity Quality Representativeness Stability Simplicity Timeliness ```

Answer 27

Cheapness

Question 28

Essential Activities of Public Health Surveillance: Defining the Health Problem: allows to decide whether the person has the disease or not Case definition for surveillance Operational definition of the health problem for it to be accurately and reliably recognized and counted Might differ from the following: Clinical criteria for diagnosing the disease Case definition of the disease used in outbreak investigations Ex: Follows a very strict criteria for every type of case

Answer 28

Identify, define, and measure the health problem of interest

Question 29

A person with sudden onset of fever (> 38.50C rectal or 38C axillary) and one of the following signs: - neck stiffness - altered consciousness - other meningeal sign

Answer 29

Suspected Case

Question 30

A suspected case with CSF examination showing at least one of the following: - turbid appearance - leukocytosis - elevated protein - decreased glucose

Answer 30

Probable Case

Question 31

A suspected case that is laboratory-confirmed

Answer 31

Confirmed Case

Question 32

uses less specific criteria Used when identifying and counting the occurrence of a disease consist of a constellation of signs and symptoms, chief complaints or presumptive diagnosis, rather than the specific clinical or laboratory diagnostic criteria

Answer 32

Syndromic Surveillance Goal: earlier detection of an unusual increase in illnesses than the traditional surveillance might to facilitate early intervention Data sources: emergency departments, relies on computer methods to identify deviation from the baseline

Question 33

ODD MAN OUT: Defining the Scope of Surveillance Geographic area Population covered Resources Time period

Answer 33

Resources

Question 34

Essential Activities of Public Health Surveillance: From multiple sources using selected methods; data from this sources might originally be collected for purposes that are different from the objectives of the surveillance

Answer 34

Collect and compile data about the problem Understanding the natural history of the disease is critical in surveillance Determines how best to conduct surveillance for the disease

Question 35

ODD MAN OUT Typical Sources of data used in surveillance and collection of data : 1. Individual persons 2. Health care providers, facilities and records 3. Doctor’s clinic, hospital (OPD,ER), Laboratories 4. Environmental conditions : Air, water 5. Administrative actions 6. Passport 7. Financial transactions: Sales of goods and services, tax 8. Legal actions 9. Laws and regulations

Answer 35

6. Passport

Question 36

Methods of Collecting Health-Related Data: hazard surveillance supplement for surveillance and not specific to surveillance

Answer 36

Survey

Question 37

Methods of Collecting Health-Related Data: | hazard surveillance

Answer 37

Environmental Monitoring

Question 38

ODD MAN OUT: Methods of Collecting Health-Related Data Notification Registries Re-analysis of secondary data Data Editing

Answer 38

Data Editing

Question 39

Passive Vs. Active Surveillance: | Health care providers send reports to health departments on the basis of a known set of rules and regulations

Answer 39

Passive (Provider initiated surveillance)

Question 40

Passive Vs. Active Surveillance: Health departments contact health care providers to solicit reports Limited to specific diseases over a limited period of time

Answer 40

Active (Health Agency initiated surveillance)

Question 41

Relies on a pre-arranged sample of health care providers who agree to report all cases of certain conditions Sample might not be a representative of the entire population Reporting is probably consistent over time because the sample is stable and participants are committed to providing high quality data

Answer 41

Sentinel Surveillance

Question 42

Essential Activities of Public Health Surveillance: | it is when data analysis and interpretation is done

Answer 42

Analyze and interpret the data

Question 43

Basic Considerations of Analyzing and Interpreting data: | Data from individual cases are analyzed differently form data aggregated

Answer 43

Different data imply different types of analysis

Question 44

Basic Considerations of Analyzing and Interpreting data: Computation of rates of disease or other health-related condition Description of the occurrence of disease in terms of person, place and time To determine whether the incidence/prevalence has changed

Answer 44

Descriptive methods are usually appropriate

Question 45

Basic Considerations of Analyzing and Interpreting data: Health problem, temporal and geographic patterns of occurrence Analysis by Time

Answer 45

Selection of data for comparison depends on:

Question 46

A if only the first statement is correct B if only the second statement is correct C if both of the statements are correct D if neither of the statements is correct Analysis by Time 1. Purposes is to characterize trends and detect changes in disease incidence 2. Data organization does not include tables, graphs or combination

Answer 46

A

Question 47

A if only the first statement is correct B if only the second statement is correct C if both of the statements are correct D if neither of the statements is correct Methods of Analysis by Time 1. Comparison of the number of case reports received for the current week with the number received in the preceding weeks. 2. Comparison of the number of cases during the current period to the number reported during the same period for the last 2-10 years

Answer 47

C

Question 48

A if only the first statement is correct B if only the second statement is correct C if both of the statements are correct D if neither of the statements is correct Methods of Analysis by Time 1. Description of the case reports 2. Analysis of long-term time trends

Answer 48

B

Question 49

A if only the first statement is correct B if only the second statement is correct C if both of the statements are correct D if neither of the statements is correct Analysis by Place 1. Rates are often calculated by adjusting for differences in population size 2. Rates are usually hidden and not displayed in a table or a map

Answer 49

A

Question 50

A if only the first statement is correct B if only the second statement is correct C if both of the statements are correct D if neither of the statements is correct Analysis by Place and Time 1. Disease occurrence is often analyzed by time and place simultaneously 2. Analysis can be organized and presented in: (Tables Series of maps highlighting different periods or populations)

Answer 50

C

Question 51

thematic map used to represent the statistical data through various shading patterns or symbols on predetermined geographic areas Other sophisticated applications following the advent of geographic information systems

Answer 51

Choropleth maps or spot and shaded maps

Question 52

A if only the first statement is correct B if only the second statement is correct C if both of the statements are correct D if neither of the statements is correct Analysis by Person 1. Most common person characteristics are age, sex, race and ethnicity 2. Person variables useful for analysis do not depend on the health problems

Answer 52

A

Question 53

TRUE OR FALSE: | Standard categorization of age must not be mutually exclusive and all inclusive

Answer 53

FALSE Mutually exclusive: end of one category cannot overlap with the beginning of the next category All inclusive: categories should include all possibilities including the extremes of age and unknowns

Question 54

Interpreting result of analysis: Increase in the incidence Variation in pattern of disease in a specific population at a particular time and place from what is expected

Answer 54

Scenario

Question 55

Interpreting result of analysis: Further investigation Prevention or control measures

Answer 55

Response

Question 56

ODD MAN OUT: Common causes of artifactual or artificial changes: ``` Changes in case definition Laboratory error Duplicate reporting Tampering of data Increase in population size Ne lab test / diagnostic procedure Batch reporting ```

Answer 56

Tampering of data

Question 57

Essential Activities of Public Health Surveillance: Disseminating Data and Interpretations Timely, regular dissemination of basic data and their interpretation is a critical component of surveillance

Answer 57

Provide these data and their interpretation to those responsible for controlling health problem Providers of reports Persons, agencies or institutions who use surveillance data for planning or managing control programs, administrative purposes or other health related decision making

Question 58

Essential Activities of Public Health Surveillance: Purpose of Evaluating Surveillance Systems Identifies elements of surveillance that should be enhanced to improve its attributes Improves the quality of data and interpretations provided by surveillance Assesses how surveillance findings affect control efforts

Answer 58

Monitor periodically, evaluate the usefulness and quality surveillance to improve it for future use

Question 59

Framework of Public health surveillance and action: Aggregated reports from PIDSR are incorporated into the annual morbidity report of the Field Health Services Information System

Answer 59

Philippine Integrated Disease Surveillance and Response (PIDSR)

Question 60

Four Major Disease Surveillance Systems prior to PIDSR: Hospital-based surveillance system that yields information on admitted cases of diseases with outbreak potential in sentinel hospitals and which can serve as an early warning system for epidemics in the community

Answer 60

National Endemic Sentinel Surveillance System (NESS)

Question 61

Four Major Disease Surveillance Systems prior to PIDSR: Monitoring of priority vaccine-preventable diseases targeted for eradication and elimination, namely: poliomyelitis, measles and neonatal tetanus

Answer 61

VPD Surveillance: vaccine-preventable diseases

Question 62

Four Major Disease Surveillance Systems prior to PIDSR: | Keeps track of the number of HIV-AIDS cases through a voluntary testing program.

Answer 62

HIV-AIDS Registry

Question 63

Four Major Disease Surveillance Systems prior to PIDSR: | Generates information on 17 diseases and 7 syndromes

Answer 63

Notifiable Disease Reporting System (NDRS)

Question 64

Approaches of PIDSR: ``` reports of cases and events come from diseases reporting units (DRUs) Community Barangay health stations Rural health units City health offices Government/private hospitals or clinics Government/private laboratories Ports and airports ```

Answer 64

Facility and community based approaches

Question 65

Approaches of PIDSR: | set of data collected for every case of notifiable disease or syndrome seen or detected on the DRUs

Answer 65

Case-based data collection