Double-Blind Trials

Biology: AQA GCSE Higher, topic 3.1.22

Double-Blind Trials

In clinical trials, some patients are given a placebo (an alternative that does not contain any of the drug). Whether a patient gets the drug or the placebo is randomly chosen. Neither the patient nor the doctor knows who has received which.

Unbiased

Double-blind trials make sure that a test is perfectly fair.
If either the patient or doctor knew what they were taking, it could skew the outcomes of the trial.

Identical conditions

All the conditions are kept identical across the two groups so that only the drug has an impact on a patient’s health.

Test yourself on Double-Blind Trials

In a double-blind trial, who knows which patients are taking the placebo?
Why are double-blind trials used when testing new drugs?

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