The Burden of Stroke Scale (BOSS) provides valid and reliable score estimates of functioning and well-being in stroke survivors with and without communication disorders

Abstract

Background and objective: This study describes the conceptual foundation and psychometric properties of the Burden of Stroke Scale (BOSS), a patient-reported health status assessment designed to quantify the physical, cognitive, and psychological burden of stroke.

Methods: Qualitative research methods were used to develop a 112-item pilot version of the instrument. The pilot version was administered to healthy controls (n=251) and stroke survivors with (n=135) and without (n=146) communication disorders on a single occasion for the purposes of reducing the global item pool, describing the resulting scale properties, examining the dimensionality of the burden of stroke construct, and examining the known-groups validity of the instrument.

Results: Sixty-four items were retained, comprising 12 internally consistent and unidimensional scales. Principal components analysis revealed three second-order factors (Physical Activity Limitations, Cognitive Activity Limitations, and Psychological Distress) comprising the Burden of Stroke construct. Comparisons between groups revealed that stroke survivors reported greater activity limitations and psychological distress on all scales relative to controls, and that stroke survivors with communication disorders reported greater activity limitations on swallowing, communication, cognition, and social relations scales relative to non-communicatively disordered stroke survivors.

Conclusion: These findings support the internal consistency of the BOSS scales, the hypothesized dimensionality of the burden of stroke construct, and the known-groups validity of the instrument.