Article

We aimed to verify by Rasch analysis whether the Mini-BESTest, a balance measure,
confirms its main psychometric properties in patients with subacute stroke
undergoing rehabilitation in three different countries
(Slovenia, Croatia, and
Italy), and to examine the stability of item hierarchy and difficulty across the
three national versions through a differential item functioning analysis. We
investigated 159 patients with subacute stroke consecutively admitted to three
rehabilitation facilities after screening for an intensive, tailored
rehabilitation program. Balance function was tested within 36 h from admission
and after approximately 25 days. As no differential item functioning was found
between admission and discharge data or among countries, all data were pooled.
Rasch criteria for the functioning of rating scale categories were fulfilled. In
terms of internal construct validity, all items except item #14 (Cognitive Get Up
& Go; infit value=1.42) showed an acceptable fit to the Rasch model. The patient
ability-item difficulty matching was very good. Reliability indices were high.
The Principal Component Analysis of standardized residuals confirmed the
unidimensionality of the test. On the basis of the item calibration, raw scores
of the Mini-BESTest were transformed into linear estimates of dynamic balance and
six statistically detectable levels of balance ability were defined. Good
psychometric features of the Mini-BESTest were confirmed. The three different
national versions showed stability in item hierarchy, indicating equivalence of
their cross-cultural adaptations. Problems with item #14 in these patients
warrant further study.

Langue : ANGLAIS