Evidence labels describe how information was produced. They do not automatically determine whether a claim is strong or weak; the design must fit the question and be interpreted within its limits.
Laboratory evidence
Laboratory work can examine cells, tissues, chemical interactions, or measurement methods under controlled conditions. FDA's preclinical research overview places laboratory and animal work before studies intended to establish how an investigational drug behaves in people.
Animal evidence
Animal studies can investigate biological mechanisms and predefined outcomes in nonhuman models. Results should be described as animal findings, not silently converted into conclusions about people. FDA identifies pharmacology and toxicology work as part of the preclinical information considered before proposed human research.
Observational human evidence
In an observational study, investigators assess outcomes without assigning participants to an intervention. ClinicalTrials.gov defines observational and interventional studies separately in its official glossary.
Interventional clinical evidence
Interventional studies prospectively assign participants to one or more interventions so investigators can evaluate specified outcomes. FDA's clinical research overview describes clinical research phases and the questions each phase is designed to address.
Regulatory evidence
A regulator's review concerns a submitted product and its proposed conditions of use. It should not be collapsed into a general statement about every material that shares a related name.
A useful reading habit
Use the narrowest accurate sentence: state the model, population, comparison, measured outcome, and study status. Then state what the study did not establish.
Source record
Authoritative sources
- U.S. Food and Drug Administration Step 2: Preclinical Research
- U.S. Food and Drug Administration Step 3: Clinical Research
- ClinicalTrials.gov Glossary Terms