“Reliable Change Index”, 2014 (; backlinks):
Reliable Change Index (RCI) is a concept in measurement and assessment. An RCI is a psychometric criterion used to evaluate whether a change over time of an individual score (ie. the difference score between two measurements in time) is considered statistically-significant.
Computationally, RCIs represent a ratio, in which the numerator represents an actual observed difference score between two measurements, and the denominator is some form of standard error of measurement of the difference. An RCI indicates whether an individual change score (eg. between a patient’s pre-intervention and post-intervention assessment) is statistically-significantly greater than a difference that could have occurred due to random measurement error alone.
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