The NPIS Model: A Standardized, Consensus-Based Framework for Evaluating Non-Pharmacological Interventions

Background. The term non-pharmacological intervention (NPI) refers to health prevention and care protocols supervised by healthcare professionals. However, no precise and widely adopted definition currently exists. Additionally, unlike drugs, NPIs lack a global evaluation framework due to the absence of consensus among stakeholders, driven by the heterogeneity of intervention content and study protocols. This heterogeneity limits scientific impact, hinders dissemination and continuous improvement of practices, and contributes to significant mistrust among professionals and users. Method. From 2022 to 2023, we conducted a consensus study, collaborating with over 1,000 stakeholders—including researchers, healthcare users, healthcare practitioners, health operators, scientific societies and health authorities—to co-construct a NPI definition along with a framework for evaluating NPIs that aligns with their specific characteristics and international health research standards. This framework—the NPIS Model—was developed under the guidance of a multidisciplinary committee of 22 experts through iterative, open, and documented exchanges across four stages: i) creation of an initial list of ethical and methodological items by a committee of 70 members, ii) refinement of this list by a committee of 300 members, iii) open voting on each item by 503 voters, and iv) consultation with 36 scientific societies and 14 health authorities. Findings. We reached a consensus defining an NPI as an "evidence-based, effective, personalized, non-invasive health prevention or care protocol, registered and supervised by a qualified professional". Based on this definition, we developed the NPIS Model, which includes 77 recommendations for evaluating NPIs—14 ethical and 63 methodological. Each recommendation received at least 80% agreement among voters. The recommendation are categorized into five types of studies: mechanistic, observational, prototypical, intervention, and implementation. To date, the NPIS Model has been endorsed by 31 scientific societies and three health authorities. Interpretation. The NPIS Model promotes transparency, methodological rigor, ethical standards, and transferability for NPI research, increasing the value of NPIs for researchers, healthcare practitioners, healthcare users, and health authorities.