Psychometric Evaluation of the Interpersonal Mindfulness Scale Using Rasch Analysis

The 27-item Interpersonal Mindfulness Scale (IMS) was recently developed to assess mindfulness as it occurs during interpersonal interactions but its psychometric properties have not been evaluated for compliance with fundamental principle measurement using Rasch analysis.

A Partial Credit Rasch model was applied to investigate the psychometric properties of the IMS in a sample of 584 participants who completed the scale in English.

With 3 super-items combining related items of the three domains including nonjudgmental presence, awareness of self and others, and nonreactivity, the IMS meets expectations of the unidimensional Rasch model (χ² (27) = 33.61, p = 0.18) and demonstrated good reliability (PSI = 0.76). This permitted transformation from ordinal to interval measure based on person estimates of the Rasch model with the converging algorithm presented in a table.

These findings support robust psychometric properties, reliability, and internal validity of the IMS. Transformation of the ordinal IMS responses into interval-level data using Rasch conversion tables published here enhances the accuracy of measurement and suitability of data for parametric statistical tests without violating their fundamental assumptions.