experimental group
C1Academic / Scientific / Technical
Definition
Meaning
In scientific research, the group of subjects or participants that receives the treatment or intervention being tested.
The set of individuals, items, or data points exposed to a specific variable in a controlled study to compare outcomes against a control group. In broader terms, can refer to any team or cohort designated to test new methods, processes, or technologies.
Linguistics
Semantic Notes
The term is almost exclusively used in contexts of formal research, experimentation, or pilot studies. It implies a deliberate, structured comparison.
Dialectal Variation
British vs American Usage
Differences
No significant lexical or syntactic differences. Spelling remains consistent.
Connotations
Identical connotations of scientific rigour and controlled testing in both varieties.
Frequency
Equally high frequency in academic writing in both UK and US contexts.
Vocabulary
Collocations
Grammar
Valency Patterns
The [researchers] assigned [20 participants] to the experimental group.The experimental group received [the new drug].We compared the experimental group with [the control group].Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “None. The term is technical and not used idiomatically.”
Usage
Context Usage
Business
Used in product development or A/B testing contexts (e.g., 'The experimental group of users saw the new interface').
Academic
Core term in research methodology across sciences and social sciences.
Everyday
Rarely used outside of discussing studies or tests.
Technical
Precise term in statistics, psychology, medicine, education research, etc.
Examples
By Part of Speech
adjective
British English
- The experimental-group data showed a significant improvement.
- We analysed the experimental-group participants separately.
American English
- The experimental group data showed significant improvement.
- We analyzed the experimental group participants separately.
Examples
By CEFR Level
- In the science lesson, the teacher had an experimental group and a control group for the plant growth test.
- The researchers assigned half the volunteers to the experimental group, which received the new training programme.
- The efficacy of the vaccine was demonstrated by a 95% reduction in cases within the experimental group compared to the placebo group.
Learning
Memory Aids
Mnemonic
Think: 'EXPERIMENT-al group' – the group that gets the EXPERIMENT.
Conceptual Metaphor
A TEAM ON A TEST MISSION. The group is sent into a controlled 'mission' (the experiment) to gather data.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid direct translation that implies 'экспериментальная группа' only as a group of people conducting an experiment. In English, it is the group being experimented *on*.
- Do not confuse with 'focus group' (фокус-группа), which is for discussion, not controlled testing.
Common Mistakes
- Using it to mean a group that is unpredictable or 'experimental' in a casual sense (e.g., 'Our band is an experimental group').
- Omitting the definite article 'the' in formal writing (e.g., 'Participants in experimental group...' should be '...in the experimental group').
Practice
Quiz
In a double-blind drug trial, who knows which participants are in the experimental group?
FAQ
Frequently Asked Questions
Its purpose is to measure the effect of a specific variable or intervention by providing a basis for comparison against a group that does not receive it (the control group).
Yes, a study can have multiple experimental groups, each receiving a different variation or dosage of the treatment being tested.
No, it can be used for animals, plants, cells, schools, companies, or any unit of analysis in a research design.
A pilot group is a small-scale preliminary test, often used to refine a procedure. An experimental group is part of the formal, controlled study designed to test a specific hypothesis.