Diagnostic Testing
This measure represents the proportion of individuals with disease who test positive.
What is Sensitivity?
Routine reporting of diseases from hospitals and laboratories to health departments.
What is Passive Surveillance?
The number of new cases of disease occurring in a population during a specified time period.
What is Incidence?
Bias that occurs when individuals with disease remember exposures differently than those without disease.
What is Recall Bias?
Screening performed for an entire population regardless of risk.
What is Mass Screening?
This measure answers the question: “If the test is positive, what is the probability the person truly has the disease?”
What is Positive Predictive Value (PPV)?
Public health officials actively contacting hospitals and laboratories to identify cases.
What is Active Surveillance?
The total number of existing cases of disease in a population at a given time.
What is Prevalence?
Bias caused by inaccurate instruments or inconsistent data collection.
What is Measurement Bias?
Screening that occurs when patients seek care for another reason.
What is Opportunistic Screening?
What test measures are impacted when prevalence increases?
PPV and NPV
Surveillance conducted at selected reporting sites used to represent broader disease trends.
What is Sentinel Surveillance?
This measure reflects the proportion of diagnosed cases that result in death.
What is Case Fatality Rate (CFR)?
Bias occurring when earlier detection appears to increase survival time even though disease progression is unchanged.
What is Lead-Time Bias?
Screening that uses several tests at the same time to detect multiple diseases.
What is Multiphasic Screening?
A test with very high specificity is most useful for this purpose.
What is ruling in disease (SPIN)?
A surveillance system that tracks symptoms like fever and cough before diagnoses are confirmed.
What is Syndromic Surveillance?
This measure estimates the proportion of all infections, including undiagnosed cases, that result in death.
What is Infection Fatality Ratio (IFR)?
Bias occurs when screening detects slow-progressing disease more often than aggressive disease.
What is Length-Time Bias?
Screening tests should prioritize this test characteristic.
What is High Sensitivity?
These four measures evaluate diagnostic test performance.
What are Sensitivity, Specificity, PPV, and NPV?
These three attributes help evaluate surveillance systems according to CDC guidelines.
Surveillance system attributes:
--- Simplicity
--- Flexibility
--- Data quality
--- Acceptability
--- Sensitivity
--- Predictive value positive
--- Representativeness
--- Timeliness
--- Stability
This mortality measure reflects deaths in the entire population regardless of cause.
What is Crude Mortality Rate (CMR)?
Bias that occurs when study participants are not representative of the target population.
What is Selection Bias?
Confirmatory tests should prioritize this test characteristic.
What is High Specificity?