Propiedades psicométricas de la Escala Observacional de la Marcha del Sujeto con Amputación de la Extremidad Inferior

BACKGROUND The aim of this study was to examine the psychometric properties of the Observational Gait Scale for Individuals with Lower Limb Amputation, including intra- and inter-rater reliability, minimal detectable change, and construct validity.

METHODS An observational study was conducted in individuals with unilateral lower limb amputation. Gait was recorded under standardized conditions and independently assessed by two trained evaluators using the Observational Gait Scale for Individuals with Lower Limb Amputation, which comprised two sections: 1 - assessment of kinematic gait patterns focused on joint mobility, and 2 - assessment of spatiotemporal parameters. Intraclass correlation coefficient, Bland-Altman plots and Pearson's correlation with the Houghton Scale were used.

RESULTS Thirty-seven participants were included, 56.8% women and mean age 45.6 years (SD=13.8). Intra-rater reliability was excellent for the total score (ICC = 0.996), section 1 (ICC = 0.988), and section 2 (ICC = 0.995) with an MDC95 of 0.12 points. Inter-rater reliability was also excellent (total ICC = 0.987; section 1 = 0.966; section 2 = 0.986), with an MDC95 of 0.36 points. Bland-Altman analysis showed narrow limits of agreement (±1.4 points intra-rater and ±2.28 points inter-rater). Construct validity was strong and statistically significant (r= -0.773; p <0.001).

CONCLUSIONS The Observational Gait Scale for Persons with Lower Limb Amputation is a reliable and valid tool for assessing an objective and structured evaluation of gait patterns in individuals with unilateral lower limb amputation. Its design, excellent reliability and strong construct validity support its use in both clinical practice and research.