Minimal Clinically Important Difference
Also written as: MCID — Minimal Clinically Important Difference
The smallest change in an outcome measure score that a patient or clinician would consider meaningful, used as a benchmark to determine whether a rehabilitation intervention has produced a genuine benefit.
Full Definition
The minimal clinically important difference (MCID) represents the threshold of change on a standardised outcome measure below which a score difference is considered statistically unreliable or clinically trivial, even if statistically significant. In aural rehabilitation, MCIDs have been established for tools such as the APHAB, GHABP, and IOI-HA, allowing clinicians to distinguish genuine functional improvement from measurement noise. The MCID is established through anchor-based or distribution-based methods and is instrument-specific. Editors must ensure the correct instrument's MCID is cited and that the term is not confused with the minimum detectable change (MDC), which is a purely statistical concept.
Usage
Usage note: MCID is instrument-specific; always pair the acronym with its reference outcome tool. Do not use as a synonym for 'minimum detectable change', which is a purely statistical measure of reliability.
In Context
- "The post-intervention improvement of 22 points on the APHAB exceeded the established MCID, supporting the clinical effectiveness of the group programme." — Randomised controlled trial results section
- "Editors should ensure authors specify the MCID relevant to each outcome scale, as the value differs substantially across instruments." — Journal submission style guide note