Developing consolidated guidelines for reporting and evaluation of studies using transcranial electrical stimulation (CoRE-tES): protocol for an international Delphi study and expert consensus process

Introduction In recent decades, transcranial electrical stimulation (tES) has become a widely used non-invasive method for modulating brain function in clinical and non-clinical populations. However, existing tES trials exhibit substantial methodological heterogeneity, often limiting the reproducibility and interpretability of findings. There currently exists a paucity of consensus-driven, standardised recommendations outlining the key factors that should be reported and/or controlled in tES studies. Accordingly, this project aims to develop Consolidated Guidelines for Reporting and Evaluation of studies using tES (CoRE-tES), a tool designed to assess the methodological quality and reporting of laboratory-based and home-based tES studies. These guidelines will support improved quality, consistency, replication and transparency in research involving tES modalities, including transcranial direct current stimulation, transcranial alternating current stimulation and transcranial random noise stimulation.Methods and analysis CoRE-tES will be developed and disseminated over five stages. Stage 1 will comprise a review of recent tES literature to assess methodological and reporting quality. Stage 2 will employ a Delphi process to seek agreement among international tES experts on a list of items for inclusion in CoRE-tES. In stage 3, a consensus meeting will be held to synthesise and prioritise the agreed items to form CoRE-tES. Stage 4 will involve production of the final CoRE-tES checklist and an accompanying evaluation and elaboration document. In stage 5, CoRE-tES will be disseminated via journal publication, conferences, professional meetings and social media campaigns.Ethics and dissemination Ethics approval has been obtained from the Western Sydney University Human Research Ethics Committee (approval number H16803). Findings will be disseminated through scientific conferences and peer-reviewed journal publications, and CoRE-tES will be indexed on the Enhancing the QUAlity and Transparency Of health Research Network website.