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Study Design & Methodology Flashcards

7 cards from real CPI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Study Design & Methodology flashcards as text

  1. A PI wants to minimize selection bias in a clinical trial. Which allocation method is most effective?

    Answer: Concealed randomization

    Concealed randomization (allocation concealment) prevents investigators from predicting or influencing group assignments, minimizing selection bias.

  2. In a dose-response study, what does a monotonic relationship between dose and response indicate?

    Answer: The response consistently increases or decreases with dose

    A monotonic dose-response relationship means the response consistently moves in one direction (up or down) as the dose increases, supporting causality.

  3. Which term describes the ability of a study to detect a true effect when one exists?

    Answer: Statistical power

    Statistical power (1-β) is the probability of correctly rejecting a false null hypothesis, i.e., detecting a real effect.

  4. A researcher uses historical medical records to follow patients forward in time from exposure to outcome. This is a:

    Answer: Historical prospective cohort study

    A historical prospective cohort study uses existing records to reconstruct cohort exposure and then tracks outcomes forward in time.

  5. When calculating sample size for a clinical trial, increasing the desired power from 80% to 90% will:

    Answer: Increase required sample size

    Higher power requires detecting smaller or less likely effects, necessitating a larger sample to achieve that statistical certainty.

  6. A study designed to detect a clinically meaningful difference of 5 mmHg in blood pressure uses 80% power and α=0.05. If the true effect is 3 mmHg, the study is likely to:

    Answer: Commit a Type II error

    When the true effect is smaller than the detectable difference the study was powered for, it is underpowered and likely to miss the effect (Type II error).

  7. Equipoise in clinical research means that:

    Answer: Genuine uncertainty exists about which treatment is superior

    Clinical equipoise refers to genuine uncertainty in the medical community about which treatment is better, ethically justifying a randomized trial.