Clinical Trials: Phases, Endpoints and Why Most Candidates Fail · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

What a trial result is allowed to claim

Science · The Human Body · ages 23-24
Name ______________________   Date ____________

  1. Why randomize instead of letting doctors choose who gets treatment?

    • It balances even unmeasured factors between groups
    • It makes the trial cheaper
    • It removes the need for consent

  2. What do early trial phases establish?

    • Real benefit against standard care
    • Safety and the dose humans tolerate
    • The drug price

  3. Blinding protects the endpoint from expectations of patients, doctors, and scorers alike.

    Circle one:   True   False

  4. A drug improves a blood marker but patients feel and survive the same. What has it shown?

    • Only a surrogate move, not clinical benefit
    • Proof of safety
    • Real clinical benefit

  5. Treatment events run at 6 per 100, control at 12 per 100. What is the relative risk on treatment?

    • 2
    • 6
    • 0.5

  6. Where do efficacy failures cluster, and what does that say?

    • At safety testing, showing bad luck
    • Where real benefit must first be shown, pointing back at weak target choice
    • At consent review, showing bad paperwork

  7. A relative risk of 0.5 on a surrogate marker proves patients live longer.

    Circle one:   True   False

  8. A protocol tests a risky drug in a vulnerable group with thin consent. What is your call?

    • Approve it if the marker endpoint is novel
    • Approve it for the knowledge gained
    • Send it back: consent must be informed and free, risk proportionate
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Answer key

For grown-ups. Fold this page away before handing over the rest.

What a trial result is allowed to claim W1-mt_xKBKzSYxLh-s1

  1. It balances even unmeasured factors between groups · Assignment by chance, not judgement, resists hidden bias.
  2. Safety and the dose humans tolerate · Safety and tolerable dose come before any activity claim.
  3. True · Expectations bend treatment, reporting, and scoring without blinding.
  4. Only a surrogate move, not clinical benefit · Markers are stand-ins; feeling and survival are the clinical facts.
  5. 0.5 · Divide the treatment rate by the control rate: 6 over 12 is one half.
  6. Where real benefit must first be shown, pointing back at weak target choice · Benefit gates expose validation gaps carried in from earlier stops.
  7. False · The ratio describes the marker rate only, not survival.
  8. Send it back: consent must be informed and free, risk proportionate · Review rails gate every phase regardless of scientific appeal.
Worksheet · LightMySky