A new cutoff score for the Burke Lateropulsion Scale improves validity in the classification of pusher behavior in subactue stroke patients

Abstract

BackgroundPusher behavior substantially hampers balance during sitting, standing, and posture transitions in stroke patients. The Burke Lateropulsion Scale (BLS) was recommended to evaluate pusher behavior. However, its cutoff score has not been validated and recent studies found evidence for a need to modify it. As there is no gold standard for the diagnosis of pusher behavior, functions that are typically disturbed in these patients should be used for the validation of the cutoff score. Research questionTo investigate whether pusher behavior correlates with balance performance during sitting, standing and posture transitions, and to validate the BLS cutoff score. Methods44 subacute stroke patients with pusher behavior (BLS ≥ 2) were included in this study. The BLS and the Performance-Oriented Mobility Assessment Balance subscale (POMA-B) were assessed several times at intervals of two weeks resulting in a total of 137 data sets. ResultsCorrelation analysis between the BLS score and the POMA-B score revealed a moderate negative correlation (rSp=-0.602, p < 0.001): The lower the BLS score, the higher the balance performance. The maximum Youden Index (J=0.864) was found for a cutoff score ≥2.5. Patients with a BLS score ≥2 scored ≥1 on the POMA-B, while patients with a BLS score ≥3 scored at no item or only at the sitting balance task. SignificanceIn line with previous findings, the results of this study support using a BLS cutoff score of ≥3 instead of ≥2 to diagnose PB for research purposes and intervention planning. A score ≥3 correlates with severe balance impairments and with an impaired verticality perception in the frontal plane, and it improves the agreement with the Scale for Contraversive Pushing.