Methodology Glossary
Research words, in plain language
Quick definitions for the terms you meet when reading about studies.
- Arm
- One of the groups in a study that follows a specific plan.
- Bias
- Any systematic error that pulls results away from the truth.
- Blinding
- Hiding group assignments from volunteers, researchers, or both.
- Case-control study
- A design comparing people with an outcome to similar people without it.
- Cohort
- A group of people followed over time in a study.
- Confounder
- An outside factor linked to both exposure and outcome that can mislead conclusions.
- Control group
- The comparison group used as a reference point.
- Crossover
- A design where each volunteer experiences more than one approach in sequence.
- Endpoint
- The specific result a study measures to answer its question.
- Consent process
- The process of learning about a study before agreeing to take part.
- Placebo
- An inactive version used for comparison that looks like the real thing.
- Protocol
- The written plan describing how a study will be run.
- Randomization
- Assigning volunteers to groups by chance.
- Sample size
- The number of volunteers a study plans to include.
- Washout period
- A pause between approaches in a crossover study.