Development of the MDMA-Assisted Psychotherapy Side Effects Tool (M-SET): a Delphi study

Julia Colcott1, Alexandre A Guerin2,3, Olivia Carter1

  • 1Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Victoria, Australia.

BMJ Open
|May 11, 2026
PubMed
Abstract

Insights

Researchers developed the MDMA-Assisted Psychotherapy Side Effects Tool (M-SET) to systematically assess adverse events during MDMA-assisted psychotherapy. This new tool aids in improving patient safety and gathering robust evidence on MDMA-AP tolerability.

Area of Science:

  • Psychopharmacology
  • Clinical Psychology
  • Therapeutic Innovation

Background:

  • Growing interest in the therapeutic potential of 3,4-methylenedioxymethamphetamine (MDMA).
  • Lack of a systematic tool to assess side effects of MDMA-assisted psychotherapy (MDMA-AP).

Purpose of the Study:

  • To develop the MDMA-Assisted Psychotherapy Side Effects Tool (M-SET).
  • To capture and evaluate side effects throughout the course of MDMA-AP.

Main Methods:

  • Systematic review and questionnaire review to draft potential side effects.
  • Modified two-round online Delphi process with 12 experts in MDMA-AP and neuropsychopharmacology for validation.
  • Expert consensus achieved through Delphi panel deliberations.

Main Results:

  • The final M-SET includes 165 items across four distinct questionnaires.
  • Information is collected at screening, baseline, medication sessions, and long-term follow-up.
  • High expert participation rates in both rounds of the Delphi process (Round 1: 83-92%, Round 2: 75%).

Conclusions:

  • The modified Delphi technique successfully generated content for the first structured tool for MDMA-AP side effects.
  • The M-SET is recommended for research and clinical use to enhance MDMA-AP safety.
  • Implementation of M-SET can support a robust evidence base for MDMA-AP safety and tolerability.