Efficacy of scrambler therapy in chemotherapy-induced peripheral neuropathy: a systematic review of randomized controlled trials

Chemotherapy-induced peripheral neuropathy (CIPN) treatment is challenging due to limited and often unsatisfactory therapy options. Scrambler therapy (ST) is gaining interest as treatment option with promising initial results. However, further evaluation is needed to confirm its effectiveness. The purpose of this review was to evaluate the efficacy of scrambler therapy in the management of chemotherapy-induced peripheral neuropathy. This systematic review followed the PRISMA guidelines and the Joanna Briggs Institute (JBI) methodology; however, the protocol was not prospectively registered in the PROSPERO database. Electronic databases (CINAHL, Scopus, Web of Science, ScienceDirect, and PubMed) were searched from January 2014 to August 2024. Only English-language randomized controlled trials were eligible. Two reviewers independently screened studies, extracted data, and appraised methodological quality using JBI critical appraisal tools. Two independent randomized controlled trials, reported across three publications, met the inclusion criteria. The sample size ranged between 35 and 50 participants, and the mean age ranged between 59 and 61 years. The overall quality assessment ranged between low to moderate risk of bias. The reviewed studies demonstrated varying results regarding the efficacy of ST in managing CIPN. Two studies suggest that ST may reduce CIPN symptoms and improve quality of life, although these effects did not reach statistical significance (p > 0.05). However, one study’s lack of significant benefit highlights treatment variability and limitations. Scrambler therapy does not yet meet statistical criteria for a successful treatment CIPN. Further RCTs with large samples, blinding, and extended follow-up is needed to validate ST effectiveness.