Effects of Lee Silverman Voice Treatment® BIG on motor symptoms in patients with Parkinson’s disease: a systematic review and meta-analysis

This review aims to examine the effects of Lee Silverman Voice Treatment® BIG (LSVT® BIG) on motor impairments, activities of daily living (ADLs), and quality of life (QoL) in patients with Parkinson’s disease (PD). PsycINFO, PubMed, EMBASE, SCOPUS, PEDro, CINAHL, and Web of Science were searched until June 2025. Studies were included if they included patients with PD, administered LSVT® BIG, and assessed motor symptoms, ADLs, and QoL. The PEDro scale was used to assess methodological quality, and pooled effect sizes were calculated using Cohen’s d and random-effects models. Ten studies (300 participants) met the inclusion criteria. No significant effects in the Time-Up & Go (TUG) test (SMD: 0.050, 95% CI: −0.550 to 0.650, p = 0.870) and the 10-Minute Walk Test (10MWT) (SMD: 0.415, 95% CI: −0.198 to 1.027, p = 0.184) were reported. Other outcome measures revealed significant improvements in balance, gait cycle symmetry, and manual dexterity in patients with PD. The initial findings revealed that LSVT® BIG improves balance and gait in patients with PD. The evidence for the effects of LSVT® BIG on manual dexterity and overall ADLs is mixed and inconclusive for QoL. Further high-quality studies with long-term follow-ups are needed. Lee Silverman Voice Treatment® BIG (LSVT-BIG®) improves balance and gait in patients with Parkinson’s disease (PD).Therapists should provide consistent, intensive practice to support functional mobility and daily activity performance. Lee Silverman Voice Treatment® BIG (LSVT-BIG®) improves balance and gait in patients with Parkinson’s disease (PD). Therapists should provide consistent, intensive practice to support functional mobility and daily activity performance.