Sham tDCS controls: blinding, reliability, and a specification-grade checklist
Gordon C. Baylis
Sham transcranial direct current stimulation (tDCS) is essential for causal inference but is commonly implemented as ramp-only protocols that may not ensure physiological inertness and may fail to maintain mid-session blinding. We synthesize evidence on sham blinding integrity and test–retest reliability from January 1, 2010, to August 31, 2024, with a targeted post-search update (September 2024–September 2025) for key methodological advances directly informing sham design, blinding assessment,