Surveillance

Question 1

Surveillance systems should support a system that can identify risk factors for infection and other adverse advents, implement risk-reduction measures and monitor the effectiveness of interventions.

Answer 1

Programs should be integrated to include IPAC, performance improvement, patient safety, emergency preparedness, and public health activities.

Question 2

Surveillance can be defined as a comprehensive method of measuring outcomes and related processes of care, analyzing the data, and providing information to members of the healthcare teams to assist in improving those outcomes.

Question 3

Sensitivity

Answer 3

the ability of a test, case definition, or surveillance system to identify true cases or persons who have the health condition of interest. the proportion of persons with a health condition correctly identified by a a test or case definition as having the health condition.

Question 4

Specificity

Answer 4

the ability of a test, case definition or surveillance system to exclude persons who do not have the health condition of interest.

Question 5

validity

Answer 5

degree of measurement, test, study or other data collection method actually measures or detects what is intended to measure.

Question 6

Ratios

Answer 6

A ratio can be used to express a relationship between two independent groups.

Numerator (device Days) are independent of denominator (patient-days)

eg: Ratio of male to female VAC cases in ICU
(X/Y) x 10 n. 4/2 x1.

Question 7

Proprotion

Answer 7

A ratio in which the population in the numerator is a subset of the population in the denominator. Frequently expressed as a percentage.

Question 8

Incidence Rate

Answer 8

Measures the occurrence of new cases or events in a specific population during a given time period.
x/y x 10n

X (numerator) is the number of new cases or events in a population during that time.
Y (denominator) is the number of in the population at risk during that time.

Denominator differs depending on the study being conducted.

Question 9

In person-time incidence rates, the denominator is the sum of the time each person was at risk in a specified time period, totaled for all persons.

Question 10

Attack rate- is actually an incidence proportion rather than a true rate, used to describe the frequency of cases during an outbreak.

Answer 10

eg. 11 of 46 people at the picnic developed GI.

11/46 x 100= 23.9%

Question 11

Prevalence Measures

Answer 11

Occurrence of existing (old and new) in a specific population during a given time period.

Question 12

Measures of central tendency

Mean
Median

Answer 12

Mean: mathematical average. affected by outliers
Median: middle value in a ranked set of data- not impacted by outliers

Question 13

Range

Answer 13

difference between smallest and largest

Question 14

Deviation

Answer 14

difference between individual value in a data set and the mean

Question 15

Variance

Answer 15

deviation around the mean of a distribution

Question 16

Standard deviation

Answer 16

reflects the distribution of values around the mean

Question 17

Percentiles

Answer 17

CDC NHSN reports percentile distributions for device associated infection rates and device utilization ratios among participating facilities.

Question 18

Methodology
Total (or Whole) House Surveillance

Answer 18

When total house surveillance is conducted, and overall facility infection rate should not be calculated. Rates should be calculated for specific HAIs in defined populations in the facility. CLABSIs in an ICU or SSIs related to a specific operative procedure.

Overall all, crude rates, are sensitive enough to identify potential problems and therefore cannot be used to target performance improvement activities.

Rates not adjusted for specific infection or injury risk., not appropriate for making comparisons over time, between groups either within a facility or between facilities, or benchmarking.

Question 19

Target surveillance- focuses on particular care units, infections related to medical devices, invasive procedures, and organisms of epidemiological significance.

Answer 19

Usually focuses on high-risk, high-volume procedures and those HAIs and adverse outcomes that are potentially preventable.

Question 20

TAP reports include the metric, CAD cumulative attributable difference, which yields a specific number of infections that must be prevented in order to reach established HAI reduction goals.

Answer 20

CDC encourages IP to utilize specific TAP reports and CAD metric that represent concrete prevention goals that are linked to standardized infection rates (SIR).

Question 21

Elements of an effective surveillance program

Answer 21

Select the surveillance methodology
Assess and define the population to be studied
Choose the events to monitor - outcomes of healthcare, processes of healthcare, selected events of importance to the organization.
Determine the time period
Identify surveillance criteria (case definitions)
Identify data elements to be collected
Determine methods for data analysis
Determine methods for data collection and management
Design an interpretive Surveillance Report
Identify recipients of the surveillance report
Develop a written surveillance plan
Surveillance program evaluation

Question 22

If rates are to be calculated, both the number of cases and the number in the total population at risk for that condition must be identifiable.

Answer 22

Rates rather than raw numbers must be used to accurately track trends over time. Select events that incorporate a risk adjustment or risk stratification method whenever possible.

Question 23

Identify data elements to be collected

Answer 23

To use time and personnel resources efficiently, data collection should be limited only to those elements that are needed to identify a case and determine whether the case criteria are met for the condition or event being studied.

Question 24

Determine methods for data analysis

Answer 24

Whenever possible, data should be expressed as rates or ratios that are calculated using the same methodology as a nationally validated surveillance system.

This allows an organization to compare its rates with another organization or a recognized benchmark.

Question 25

Determine methods for data collection and management

Answer 25

Data may be collected concurrently or retrospectively

Whenever possible, arrange to have data downloaded directly into a computerized surveillance database so they can be efficiently manipulated and analyzed.

Question 26

Design an interpretive Surveillance Report

Answer 26

Use surveillance findings to stimulate performance improvement activities.

Question 27

Identify the recipients of the surveillance report

Answer 27

Disseminate the report to those managers and healthcare providers in the organization that can use the findings to identify and implement evidence-based IPAC practices and improve outcomes.

Question 28

Surveillance Program Evaluation

Answer 28

Compare the program’s structure and activities with current evidence-based practices and published recommendations for surveillance programs in similar settings.

A surveillance program should be able to support a system that can prevent as many infections and other adverse events as possible with the resources available.

Question 29

If a hospital uses NHSN methodology to collect and analyze SSIs, then it can use the z-test and standardized infection ratio (SIR) to compare its risk-adjusted SSI rates with the rates in the NHSN system reports.

Question 30

National surveillance system for health care workers monitors for:

Answer 30

immunization, TST programs, exposures to blood and body fluids, vaccine preventable disease and TB.

Question 31

National Nosocomial Infections Surveillance System for HAI monitors infection-related events that include CLABSI, CAUTI, SSI, Ventilator-associated events, CDI, other drug resistant infections.

Question 32

Pathogens that have been linked to transmission via contaminated environmental surfaces and medical equipment include MRSA, VRE, CDI, pseudomonas aeruginosa, acinetobacter spp. norovirus.

Question 33

Active surveillance Testing= AST

The primary goal of public reporting is to increase the quality of healthcare processes and outcomes.