CPI Data Collection & Analysis Techniques 3 — Questions and Answers
Question 1: A clinical trial uses an electronic data capture (EDC) system. Which feature of EDC best supports data integrity?
- Allowing investigators to edit any field at any time without tracking
- Built-in edit checks and audit trails that record all changes (Correct answer)
- Storing data locally on site computers without backup
- Disabling query generation to reduce workload
Correct answer: Built-in edit checks and audit trails that record all changes
EDC systems with edit checks and comprehensive audit trails ensure data accuracy, completeness, and traceability per ALCOA+ principles.
Question 2: In hypothesis testing for a clinical trial, a p-value of 0.03 with an alpha level set at 0.05 means:
- There is a 3% probability the null hypothesis is true
- The result is statistically significant and the null hypothesis is rejected (Correct answer)
- The treatment effect is clinically meaningful
- The study had 97% power to detect the effect
Correct answer: The result is statistically significant and the null hypothesis is rejected
A p-value below the pre-specified alpha level (0.03 < 0.05) indicates statistical significance, leading to rejection of the null hypothesis.
Question 3: Which type of data collection instrument is MOST susceptible to recall bias?
- Electronic patient diary completed daily
- Retrospective questionnaire asking about symptoms over the past year (Correct answer)
- Wearable device logging continuous vital signs
- Laboratory assay performed at scheduled visits
Correct answer: Retrospective questionnaire asking about symptoms over the past year
Retrospective questionnaires rely on participants' memory over extended periods, making them particularly vulnerable to recall bias.
Question 4: The ALCOA-C principles for clinical data integrity stand for:
- Accurate, Legible, Consistent, Original, Attributable — Complete
- Attributable, Legible, Contemporaneous, Original, Accurate — Complete (Correct answer)
- Auditable, Legible, Compliant, Organized, Accurate — Consistent
- Accountable, Logical, Contemporaneous, Organized, Accurate — Correct
Correct answer: Attributable, Legible, Contemporaneous, Original, Accurate — Complete
ALCOA-C stands for Attributable, Legible, Contemporaneous, Original, Accurate, and Complete — the FDA's foundational principles for data integrity.
Question 5: A Data Safety Monitoring Board (DSMB) reviews unblinded interim data in a trial. What is their primary responsibility?
- Approving protocol amendments submitted by the sponsor
- Monitoring for unexpected safety signals and recommending trial continuation, modification, or stopping (Correct answer)
- Auditing source documents at investigative sites
- Setting the statistical analysis plan before enrollment
Correct answer: Monitoring for unexpected safety signals and recommending trial continuation, modification, or stopping
The DSMB independently reviews unblinded data to protect participants by recommending trial continuation, modification, or early termination based on safety and efficacy.
Question 6: Which scale of measurement allows for meaningful ratios between values (e.g., 20 mg is twice 10 mg)?
- Nominal
- Ordinal
- Interval
- Ratio (Correct answer)
Correct answer: Ratio
Ratio scales have a true zero point and equal intervals, allowing meaningful ratio comparisons between values.
Question 7: In a per-protocol (PP) analysis, which participants are typically excluded?
- Participants who received any dose of study drug
- Participants who did not meet eligibility criteria or had major protocol deviations (Correct answer)
- All randomized participants regardless of treatment received
- Participants who withdrew consent after randomization
Correct answer: Participants who did not meet eligibility criteria or had major protocol deviations
Per-protocol analysis includes only participants who adhered to the protocol without major deviations, providing an efficacy estimate under ideal conditions.
CPI Data Collection & Analysis Techniques 3
A clinical trial uses an electronic data capture (EDC) system.
Which feature of EDC best supports data integrity?