Study Design and Setting: Randomized experimental trial at Fray Bernardino Álvarez Psychiatric Hospital, Mexico City.
Sample Size: Quota sampling. Eligibility Criteria: inpatients, spanish-speaking, ≥18 years old with DSM-5 schizophrenia diagnosis, PANSS total score ≥60, and treatment with 1-2 antipsychotics (including clozapine). Exclusions: ECT within 3 months, affective comorbidities, catatonia, pregnancy, anesthesia/ECT contraindications, or incomplete follow-up.
Equipment and Technique: Pre-ECT evaluations included ECG, chest X-ray, blood tests, and assessments by internists/anesthesiologists. ECT was administered by a principal investigator (Emory University-certified) using a MECTA Corp spECTrum 5000Q device, 3x/week (excluding weekends). Electrode placement: bitemporal (BT) with brief pulses (≥0.5 ms) or right unilateral (RUL; D'Elia placement) with ultrabrief pulses (≤0.3 ms). Initial titration doses: 48 mC (BT) or 4.8 mC (RUL), doubled until adequate seizure (assessed via Clinical and Seizure Based Stimulation method). Maintenance doses: 2x threshold (BT) or 6x threshold (RUL), adjusted by 50% for poor-quality seizures. Premedication: atropine (1 mg IM), propofol (1 mg/kg IV), and succinylcholine (1 mg/kg IV).
Intervention and Comparator: Active comparator: BT-ECT vs. RUL-ECT.(intervention) No placebo group due to institutional constraints.
Randomization and Blinding: Block randomization (Microsoft Excel-generated) by an independent researcher. Allocation sequence concealed by an assistant and disclosed pre-treatment.
Outcomes: Efficacy: ≥30% PANSS reduction; Safety: Adverse event frequency/severity/time to adverse event onset. Cognition: MoCA and BACS pre-/post-ECT (administered by neuropsychology-trained staff).
Ethics: Conducted per WMA Declaration of Helsinki. Informed consent obtained from patients' legal guardians due to severe mental impairment in participants
