CTR CTR Epidemiology & Cancer Statistics 2 — Questions and Answers
Question 1: Which measure expresses the probability of dying FROM cancer (rather than with it) over a specified time period?
- Cause-specific survival rate (Correct answer)
- Overall survival rate
- Relative survival rate
- Disease-free survival rate
Correct answer: Cause-specific survival rate
Cause-specific survival counts only deaths attributed to the cancer of interest as events, excluding deaths from other causes.
Question 2: What is the primary purpose of the North American Association of Central Cancer Registries (NAACCR)?
- To set data standards and certify central cancer registries in North America (Correct answer)
- To operate the national cancer screening programs
- To fund individual hospital registry programs
- To publish clinical treatment guidelines
Correct answer: To set data standards and certify central cancer registries in North America
NAACCR develops and promotes uniform data standards, certifies central registries for data quality, and facilitates data sharing across U.S. and Canadian registries.
Question 3: In cancer epidemiology, what does a 'cohort study' examine?
- A group followed over time to observe who develops cancer (Correct answer)
- Cancer cases and matched controls interviewed about past exposures
- A cross-sectional snapshot of cancer prevalence
- Randomized patients assigned to treatment or placebo
Correct answer: A group followed over time to observe who develops cancer
A cohort study follows a defined population prospectively (or retrospectively) over time to measure cancer incidence and identify risk factors.
Question 4: Which statistic is most useful for assessing whether cancer mortality rates are declining over time in a population?
- Annual percent change (APC) in age-adjusted mortality rate (Correct answer)
- Five-year relative survival rate
- Crude incidence rate for a single year
- Stage distribution at diagnosis
Correct answer: Annual percent change (APC) in age-adjusted mortality rate
Annual percent change (APC) in age-adjusted mortality quantifies the trend direction and magnitude over time, making it the standard metric for mortality trend analysis.
Question 5: Cancer registries submit data to SEER using which standard file exchange format?
- NAACCR flat file (fixed-width text format) (Correct answer)
- HL7 FHIR JSON
- CSV spreadsheet
- XML HL7 v2
Correct answer: NAACCR flat file (fixed-width text format)
SEER and all major central registries use the NAACCR fixed-width flat file format as the standard for data submission and exchange.
Question 6: What does the term 'completeness' mean in the context of a central cancer registry's data quality?
- The proportion of all cancer cases in the catchment area that are captured by the registry (Correct answer)
- The accuracy of stage data for abstracted cases
- The timeliness of case submission to the registry
- The percentage of cases with complete treatment information
Correct answer: The proportion of all cancer cases in the catchment area that are captured by the registry
Completeness refers to the registry's case ascertainment rate — how well it captures all incident cancer cases occurring in its defined geographic population.
CTR CTR Epidemiology & Cancer Statistics 2
Which measure expresses the probability of dying FROM cancer (rather than with it) over a specified time period?