From "A Brief Definition of Mindfulness" (mindfulexperience.org):
[S]erious attention to mindfulness by the scientific community was not given until more recently when the concept was translated into measurable terms, or given an operational definition. Major strides have been made in just the last decade to provide a valid operational definition of mindfulness.
In the last decade, researchers have dedicated attention to an empirically based operational definition of mindfulness. For example, in the year 2003, a series of psychometric development studies provided the first valid and reliable measure of dispositional mindfulness called the Mindfulness Attention Awareness Scale (MAAS). Other measures of mindfulness have also been validated since that landmark study. ...
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