Identification of Potentially Inappropriate Medications for Adults Below 65 Years: Protocol for a Modified Delphi...

Polypharmacy is increasingly common across all age groups and is often associated with the use of potentially inappropriate medications (PIMs), where harms may outweigh benefits, contributing to increased adverse drug events, reduced quality of life, and rising health care costs. However, existing deprescribing guidelines and PIM criteria, such as the Beers Criteria and STOPP/START (Screening Tool of Older Persons' Prescriptions/Screening Tool to Alert to Right Treatment), primarily target older adults, overlooking the risks faced by younger populations.

This study aims to develop an international consensus-based list of PIMs for adults aged 18 to 65 years through a modified Delphi process, addressing a critical gap in medication safety and deprescribing guidance.

A 14-member international steering committee developed a preliminary list of candidate PIMs through a literature review and expert input. An international, interdisciplinary Delphi panel of 30 to 40 participants will evaluate this list across 3 survey rounds. Panelists will rate the relevance of potential PIMs using predefined criteria, including the balance of benefits and harms, patient preferences, and the availability of alternatives. Consensus will be defined as a median rating of ≥4 (for inclusion) or ≤2 (for exclusion) on a 5-point Likert scale (1=not relevant to 5=extremely relevant), with an IQR width of ≤1 and at least 70% directional agreement. Items not meeting thresholds will be carried forward to subsequent rounds for reconsideration. Quantitative analyses will summarize ratings and agreement levels, while qualitative free-text responses will undergo content analysis to provide context and capture nuanced perspectives. The process will yield a prioritized list of PIMs for adults aged 18 to 65 years.

Panel recruitment was completed between September and October 2025, with 36 participants. Three rounds of data collection were completed between October 2025 and January 2026. Interim analyses were conducted to inform structured feedback between rounds. Final data analysis is ongoing, and consensus results are expected to be reported in late 2026.

This Delphi process will yield a consensus-based list of PIMs for adults aged 18 to 65 years, informing the development of an international guideline to support safer prescribing practices and to expand deprescribing efforts beyond geriatric care.