p-Value
Definition
A statistical measure indicating the probability that observed results occurred by chance. A p-value below 0.05 is conventionally considered statistically significant, but does not indicate clinical significance or effect size.
Related Terms in Evidence & Research
Randomized Controlled Trial (RCT)
A study where participants are randomly assigned to receive either the treatment or a control (placebo or standard care). The gold standard for establishing causality in medical research.
Phase I Trial
The first stage of clinical testing in humans, typically involving 20-100 healthy volunteers. Tests safety, dosage, and side effects. Most peptides in the research pipeline are at or before this stage.
Phase II Trial
Clinical trials involving 100-300 patients with the target condition. Tests efficacy and further evaluates safety. Provides initial evidence of whether a peptide works for its intended purpose.
Phase III Trial
Large-scale clinical trials involving 1,000-3,000+ patients. Confirms efficacy, monitors adverse effects, and compares to existing treatments. Required for FDA drug approval.
Systematic Review
A comprehensive summary of all available research on a specific question, using predefined criteria to identify, evaluate, and synthesize studies. Higher evidence quality than individual studies.
Meta-Analysis
A statistical technique that combines results from multiple studies to produce a single estimate of effect. Provides the strongest form of evidence when based on high-quality RCTs.
In Vitro
Experiments performed in a controlled environment outside a living organism, such as in cell cultures or test tubes. "In vitro only" evidence is insufficient to draw conclusions about effects in humans.
In Vivo
Experiments performed in living organisms, including animal models and human subjects. In vivo evidence is stronger than in vitro but animal results do not reliably predict human outcomes.