Deep brain stimulation use in treating multiple sclerosis tremor: A practical approach for meta-analyses

Deep brain stimulation (DBS) has been introduced as a treatment option for multiple sclerosis (MS) related tremor. Recent emerging studies have investigated its efficacy and safety, yet no study has systematically assessed the evidence on this topic. Zali and colleagues have conducted the first systematic review and meta-analysis on the use of DBS in MS tremor patients. In this letter, we highlight some points in their meta-analysis regarding high heterogeneity levels that reflect some methodological concerns related to pooling studies with considerable variability. We also suggest some approaches to address this problem.