Cultural adaptation and validation of the Albanian Barthel index: A reliable tool for assessing functional independence in older adults.

BACKGROUND

The Barthel Index (BI) is a widely used instrument for assessing functional independence in activities of daily living among older adults. To date, no published, culturally adapted, and psychometrically validated Albanian version has been available. This study aimed to develop and evaluate the validity and reliability of the Albanian Barthel Index (ABI).

METHODS

A cross-cultural adaptation of the BI was conducted using standardized forward-backward translation procedures. A total of 200 participants (106 males, 94 females; mean age 69.8 ± 6.3 years) with low back pain were recruited from orthopedic and rehabilitation settings. Structural validity was examined using exploratory factor analysis with Principal Component Analysis (PCA) and Varimax rotation. Internal consistency was assessed using Cronbach's α, while inter-rater reliability was evaluated using intraclass correlation coefficients (ICC) and Cohen's κ statistics.

RESULTS

PCA demonstrated that a single dominant component accounted for most of the variance, supporting a predominantly unidimensional structure of the ABI as a measure of functional independence. All items showed strong contributions to the overall construct. Internal consistency was excellent (Cronbach's α = 0.93), indicating high item homogeneity. Inter-rater reliability was also strong, with ICC values indicating good to excellent agreement and Cohen's κ demonstrating substantial to almost perfect agreement across items. Slightly lower agreement was observed for the bathing item, though it remained within acceptable limits.

CONCLUSIONS

The ABI is a valid, reliable, and culturally appropriate instrument for assessing functional independence in Albanian adults with musculoskeletal conditions. Its use may support standardized clinical assessment, rehabilitation planning, and outcome evaluation in geriatric care settings.