CTR Follow-Up & Survival Analysis 3 — Questions and Answers
Question 1: In cause-specific survival analysis, which patients are censored?
- Patients who die from the cancer under study
- Patients who die from causes other than the cancer under study (Correct answer)
- All patients lost to follow-up
- Patients who complete the follow-up period alive
Correct answer: Patients who die from causes other than the cancer under study
In cause-specific survival, deaths from causes other than the cancer of interest are treated as censored observations.
Question 2: The expected survival rate used in relative survival calculations is derived from which source?
- Hospital mortality records
- U.S. life tables matched by age, sex, and race (Correct answer)
- National cancer incidence data
- Insurance claims databases
Correct answer: U.S. life tables matched by age, sex, and race
Relative survival uses U.S. life tables (typically Ederer II or Hakulinen method) matched by age, sex, and race/ethnicity.
Question 3: Which AJCC staging element most directly influences 5-year survival rates reported by cancer registries?
- Tumor grade
- Stage at diagnosis (Correct answer)
- Patient age at diagnosis
- Treatment facility type
Correct answer: Stage at diagnosis
Stage at diagnosis is the single most powerful predictor of 5-year survival rates and is the primary stratifier in registry survival reports.
Question 4: A registry is calculating the follow-up rate for their database. Which formula is correct?
- (Patients known alive / Total patients) × 100
- (Patients with known vital status / Total patients eligible for follow-up) × 100 (Correct answer)
- (Deaths / Total diagnoses) × 100
- (Lost to follow-up / Total patients) × 100
Correct answer: (Patients with known vital status / Total patients eligible for follow-up) × 100
The follow-up rate is the percentage of eligible patients whose vital status is known, whether alive or deceased.
Question 5: What minimum follow-up rate does NPCR recommend for reporting survival statistics?
- 70%
- 80%
- 90% (Correct answer)
- 95%
Correct answer: 90%
NPCR and SEER recommend a minimum 90% follow-up rate to ensure survival statistics are reliable and representative.
Question 6: Period analysis in survival statistics differs from cohort analysis primarily because it:
- Uses only patients diagnosed in a single year
- Provides more current survival estimates by focusing on recent follow-up intervals (Correct answer)
- Excludes patients over age 70
- Requires 10 years of follow-up data
Correct answer: Provides more current survival estimates by focusing on recent follow-up intervals
Period analysis uses the most recent follow-up intervals rather than full cohort history, providing more up-to-date survival estimates.
Question 7: Which data item should the tumor registrar record as the starting point for calculating survival time?
- Date of first treatment
- Date of diagnosis (Correct answer)
- Date of first pathology report
- Date of hospital admission
Correct answer: Date of diagnosis
Per SEER and NAACCR standards, survival time is calculated from the date of diagnosis (incidence date) to the event or censoring date.
CTR Follow-Up & Survival Analysis 3
In cause-specific survival analysis, which patients are censored?