The OPTIMUS International Consensus Guidance for Monitoring User-Reported Outcomes of Opioid Maintenance Treatment: a Delphi Study

Opioid use disorder is a major cause of drug-related harm and mortality. These can be reduced by expanded access to evidence-based and highly effective opioid agonist maintenance treatment or therapy (OMT). There is a lack of consensus on how to assess opioid use disorder treatment outcomes, and key health outcomes are often omitted. We report the results of a Delphi study to produce service user- and public health–centred international consensus guidance for OMT outcomes monitoring. An international group of 110 substance use specialists in 32 countries, including service providers, researchers and people with lived experience of OMT, produced draft guidance over multiple meetings. The guidance includes a service user-reported OMT outcomes questionnaire, based on 26 core questions, plus optional questions, in six domains (treatment, physical health, mental health, social functioning, substance use, quality of life). A Delphi panel of 757 OMT professionals and service users (46%) from 29 countries, of which 40% were female, reviewed the questionnaire over two survey rounds, supporting and improving it (round 2 mean agreement score on a 1-6 Likert scale: 5.2; 95%CI 5.1–5.3). By focusing on service user–reported and public health–centred outcomes of OMT, the OPTIMUS consensus guidance aims to facilitate the communication between service providers and service users and improve the quality of care and the survival, health and quality of life of OMT service users.