Validation and reliability of the prosthesis evaluation questionnaire-Thai version for lower-limb amputees

Abstract

BACKGROUND: Prosthesis-specific outcome measures are essential for assessing the quality of life among lower-limb amputees. While the prosthesis evaluation questionnaire (PEQ) is internationally recognized and endorsed by the International Society for Prosthetics and Orthotics through the Consensus Outcome Measures for Prosthetic and Amputation Services framework, no culturally adapted Thai version currently exists. OBJECTIVES: To translate, culturally adapt, and evaluate the psychometric properties of the Thai version of the PEQ (PEQ-TH) for use among lower-limb prosthesis users in Thailand. STUDY DESIGN: Cross-sectional validation study. METHODS: Following standard cross-cultural adaptation guidelines, the PEQ was translated into Thai, back-translated, and reviewed by a multidisciplinary expert panel. Eighty-three lower-limb amputees from 5 rehabilitation centers completed the PEQ-TH and short form 36 health survey Thai version at baseline; 71 completed the PEQ-TH again after 14 days. Psychometric evaluation included content and construct validity, internal consistency (Cronbach alpha), test-retest reliability (intraclass correlation coefficients), and floor/ceiling effects. RESULTS: The PEQ-TH demonstrated strong content validity (item-objective congruence = 0.99). Construct validity was supported by moderate correlations between PEQ-TH subscales (e.g., Ambulation, Social Burden) and corresponding short form 36 health survey Thai version domains. Internal consistency was acceptable for most subscales (α > 0.70), though Appearance, Well-Being, and Social Burden were marginally lower. Test-retest reliability ranged from moderate to good (intraclass correlation coefficient = 0.55-0.76). No floor or ceiling effects were observed. CONCLUSIONS: The PEQ-TH is a valid and reliable patient-reported outcome measure aligned with International Society for Prosthetics and Orthotics's Lower Extremity Amputation Data set and Consensus Outcome Measures for Prosthetic and Amputation Services recommendations. It enables culturally relevant assessment of prosthesis-related quality of life in Thai lower-limb amputees and supports patient-centered care and outcome monitoring.