PRISM-MX for Post-Stroke Spasticity: Cross-Cultural Adaptation and Preliminary Psychometric Evaluation in a Mexican Sample

Abstract

Objective

To perform the cross-cultural adaptation of the Patient-Reported Impact of Spasticity Measure (PRISM) into Mexican Spanish and to examine the internal consistency and preliminary convergent validity of the PRISM-MX in adults with post-stroke spasticity.

Methods

This cross-sectional pilot study included 30 adults with ischemic or hemorrhagic stroke and clinically confirmed spasticity attending an outpatient rehabilitation clinic in Merida, Mexico. Cross-cultural adaptation followed standard procedures, including forward translation, synthesis, back-translation, expert committee review, and cognitive debriefing. Preliminary psychometric evaluation included descriptive item-level analysis, internal consistency of the original 41-item PRISM-MX version, and exploratory correlations with disability, motor performance, and quality-of-life measures.

Results

The Mexican Spanish version was considered understandable, culturally relevant, and acceptable by participants during cognitive debriefing. The original 41-item PRISM-MX version was retained, and no item deletion was performed based on the present pilot sample. No missing PRISM-MX item responses were observed. Internal consistency was high for the total score (Cronbach's alpha = .956). Higher PRISM-MX scores were significantly associated with greater disability and poorer quality of life, with correlation coefficients ranging from ρ = −.46 to ρ = .61, supporting preliminary convergent validity.

Conclusions

PRISM-MX was successfully cross-culturally adapted and showed preliminary evidence of acceptability, high internal consistency, and clinically plausible associations with disability and quality-of-life indicators. Definitive psychometric validation, including structural validity, test-retest reliability, responsiveness, measurement error, and measurement invariance, remains pending.