3 × 3 model for drug use normalisation: Insights from a scoping review

• Most studies address only fragments of normalisation; only two take an integrative approach, revealing a major gap in the literature. • Drug use normalisation emerges as a dynamic, reciprocal, multi-level process. • Normalisation varies across contexts and is not a universal phenomenon, underscoring the need for contextualised analysis. • Three interconnected dimensions—access and policy, drug use, and legitimacy—operate across macro, meso , and micro levels. • A broad, integrative framework is essential for accurately assessing drug use normalisation. Drug use normalisation has been conceptualised through diverse terminologies and conceptual approaches. While early studies provided only a partial perspective, more recent research has adopted increasingly comprehensive and nuanced approaches. Despite these conceptual advancements, a unified and contemporary definition with clearly operationalised measures remains lacking. This scoping review investigates how drug use normalisation is defined and measured in the literature, to inform the development of a model assessing drug use normalisation. A systematic search was conducted across MEDLINE, PsycINFO, Embase, Web of Science, and grey literature sources for studies that focused on the normalisation of recreational illicit drugs, published from 1994 to 2024. Screening and selection followed a predefined data extraction protocol, capturing definitions and criteria. Data were analysed thematically. From 40 studies, 32 codes were identified and grouped into 10 themes across five conceptual categories: (1) Multi-Level Process, (2) Differentiated Normalisation, (3) Access and Policy, (4) Drug Use, and (5) Legitimacy. These categories constitute the foundation of a proposed 3 × 3 model, which defines drug use normalisation as a dynamic, multidimensional, and context-dependent process whereby recreational illicit drug use becomes increasingly accessible, prevalent, and perceived as legitimate across macro (societal), meso (contextual), and micro (individual) levels. The proposed model provides a comprehensive operationalisation that captures all dimensions and levels of the concept drug use normalisation. The model has the potential to improve conceptual clarity, support more consistent measurement, and inform future research, monitoring, prevention, and policymaking.