Study Design

What "comparator" means, and why it's not a formality A comparator is whatever the control group in a clinical trial receives instead of the treatment being tested. Trials commonly use one of three …

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Absolute Versus Relative Risk in a Trial: The Short Answer Relative risk tells you how many times as likely an event was in one trial group compared with the other. Absolute risk tells you how many …

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By ClinicalStudyConnect.com Research Desk You read that a study "worked better in women" or "only helped people over 60." Should you trust that difference? Often the careful answer is: not yet. A …

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A surrogate outcome is a measurement a trial uses in place of what patients care about most: how they feel, how well they function, or whether they live longer. A lab number or scan result can move in …

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You Found Out the Trial Changed — Now What? Say you or a family member enrolled in a clinical trial six months ago, or you've been following a trial's registration page while deciding whether to …

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What This Page Answers When a clinical trial reports that "12% of participants had a side effect," that number is only useful if you know three things: what group is in the denominator, how severe …

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