Natural experimental studies exist as a distinct type of experimental study.
Notes on verification
Multiple independent sources (Wikipedia, Britannica, tutor2u, peer-reviewed methodology paper) confirm natural experiments are widely recognized as a distinct study type, though some note they are technically a form of observational study rather than a true controlled experiment. [cascade flags: aggregator_dropped_primary_exists | tier=silver indep_score=0.925 clusters=2 claim_tier=everyday]
Sources
- Experiment (wikipedia)
- https://www.tutor2u.net/psychology/reference/types-of-experiment-overview (corroboration)
- https://link.springer.com/article/10.1186/s12874-021-01224-x (corroboration)