Validity, responsiveness, floor and ceiling effects of the Berg Balance Scale in patients with Guillain-Barré syndrome.

We investigated the measurement properties of the Berg Balance Scale in patients with Guillain-Barré syndrome. A retrospective analysis was performed of 81 patients with Guillain-Barré syndrome of age 17-84 years who had completed inpatient rehabilitation over a 5-year period. They were assessed with the Berg Balance Scale, the 10 Meter Walk Test, and the 6 Minute Walk Test at admission and discharge. The concurrent validity of the Berg Balance Scale was confirmed by very good correlations with the 10 Meter Walk Test at admission and discharge (ρ = 0.83 and 0.78, respectively) and by excellent and very good correlations with the 6 Minute Walk Test at admission (ρ = 0.91) and discharge (ρ = 0.77). The predictive validity of the Berg Balance Scale for the 10 Meter Walk Test and the 6 Minute Walk Test at discharge was moderate (ρ = 0.62 and 0.61, respectively) and very good (ρ = -0.87) for length of stay. The minimal clinically important difference of the Berg Balance Scale was estimated to be 10 points. The scale was highly responsive to changes in balance (Cohen's d 0.9). No floor effect was identified. A ceiling effect was identified only at discharge. The Berg Balance Scale is feasible in patients with Guillain-Barré syndrome at admission and discharge from rehabilitation. However, a ceiling effect may occur at discharge in patients with high levels of balance.