Equanimity is a non-reactive attitude that is increasingly recognized as a central component of mindfulness practice and a key mechanism of mindfulness-based interventions that is currently lacking means of measurement. The present study aimed to develop a self-report measure of equanimity, explore its underlying factor structure, validity and reliability.
An initial pool of 42 items was selected from existing mindfulness questionnaires and measures of related constructs, and subsequently reviewed by researchers and selected based on majority agreement on their construct validity. The Qualtrics online platform was used to administer these items and other questionnaires used to assess validity and collect demographic information in 223 adults from the general community (66.8% females and 33.2% males, age range = 18–75). Questionnaires were then re-administered to assess test-retest reliability.
In agreement with past research, exploratory factor analysis revealed two underlying factors, Experiential Acceptance and Non-reactivity. A final 16-item measure showed good internal consistency (⍺ = .88), test-retest reliability (n = 73; r = .87, p < .001) over 2–6 weeks and convergent and divergent validity, illustrated by significant correlations in the expected direction with the Nonattachment Scale, Depression Anxiety and Stress Scale, Satisfaction with Life Scale and Distress Tolerance Scale.
Based on this initial study, the Equanimity Scale-16 appears to be a valid and reliable self-report measure to assess trait equanimity, and may be further explored in future studies as a tool to assess progress during mindfulness-based interventions, and to assist in the investigation of their underlying mechanisms.