This criterion was established for the scientific validation of medications. It is impossible to think that psychotherapy led by a psychologist or a diet plan supervised by a dietitian can be concealed from a study participant. Every effort has been made to establish the best causal link between the proposal of a practice and its effects on health, taking into account the specificities of NPI without compromising the expected rigor and ethics of health research. Our recommendations aim to minimize biases and enhance validity and reproducibility. However, this will never prevent some individuals or promoters from committing fraud. Given the lower health risks of NPI compared to rapid-action health products (such as surgery, fast-acting medications, or implantable medical devices) and their potential interest in prevention, pragmatic real-world trials or effectiveness studies best address the consideration of risks. Additionally, the evaluation of an NPI has justified conducting an implementation study within the specific country to avoid extrapolating results from one cultural context to another.

As of April 2019, there were 46 evaluation models for NPI in the scientific literature (Carbonnel and Ninot, 2019). These models were constructed by researchers for researchers, often from a monodisciplinary perspective and rarely from a patient-centered approach. This led to significant heterogeneity in study protocols and the way NPI were conceived (approach, method, technique, or materials). The results were scattered, debatable, poorly transferable, and rarely reproducible. Consequently, these practices were not widely recognized outside the study context (dependent on the establishment and/or practitioner). This situation raised doubts about their effectiveness (e.g., efficacy, safety, relevance, utility, cost-effectiveness), their content (e.g., heterogeneity in doses, procedures, ingredients, techniques, contexts, target populations), their approval (e.g., ethics committees), their dissemination (e.g., conflicting reviewer opinions), their teaching (e.g., protocols, best practices), and their recognition (e.g., authorization, integration into official classifications, reimbursement). This lack of a consensual evaluation model for NPI suggested that each professional had to reinvent their program for every new patient, given the wide or contradictory recommendations from authorities, agencies, and scientific societies. It also implied that only the patient-provider relationship mattered in the health effects induced (Ninot, 2020). Moreover, it left the door open for pseudoscientific practices and, more broadly, parallel medicine, along with all the obscurantist, health-related, sectarian, political, and judicial issues that are known in France (Miviludes, 2022; CNOI, 2023; CNOM, 2023) and around the world (Ernst and Smith, 2018). This idea was also gaining traction in the United States in the field of oncology, aiming to juxtapose two medical offerings: one based on experimental science, primarily focused on surgery, medication, radiotherapy, and medical devices, and the other described as "complementary, integrative, or traditional," based on individual experience, opinions, and traditions (Mao et al., 2022). This second offering claimed exclusivity in the domains of prevention and care, emphasizing care for the person versus cure for the disease. Thus, the NPIS Model was co-constructed with the idea that experimental science could demonstrate the existence of effective, safe, and reproducible prevention and care protocols. This work was supported by seed funding for participatory research from INSERM and involved over 1,000 participants under the guidance of a committee of 22 multidisciplinary experts, including two user representatives. This transdisciplinary innovation is currently supported by 30 French scientific societies, the National Center for Palliative Care and End of Life, INCa, and the French Platform for Clinical Research Networks.

NPI are a field in which many amalgamations occur between scientific knowledge and opinion, due to their objective—human health—and their operational mode, which involves immaterial protocols. However, it is essential to learn to distinguish science from research amidst the multiplication of tools and information channels (Klein, 2020), particularly on the subject of NPI. The same communication channels transmit both scientific knowledge and beliefs, opinions, comments... Information of different statuses becomes intertwined. Knowledge can turn into the belief of a particular community, and vice versa.

Research, on the other hand, pertains to questions for which we do not yet have answers. These well-defined questions still have no answer. A researcher works on the subject using various methods and strategies. Research fosters doubt. Scientific societies work to advance research within a specific territory and theme.

Given that NPI are universal health protocols centered on individuals and administered by humans, an international multidisciplinary scientific society needed to be created. This has been achieved since 2021. This society is called the Non-Pharmacological Intervention Society (NPIS).

Indeed, the NPI Registry contributes to the development of precision medicine. For example, how can we advance this field in the non-pharmacological treatment of pain without confusing patients when a prestigious medical school like Stanford publishes such a vague, incomplete, and unranked list on its website?

• Physical activity
• Acupressure
• Acupuncture
• Application of heat or cold
• Aquatherapy
• Art therapy
• Biofeedback
• Family coaching
• Individual coaching
• Psychological conditioning
• Desensitization
• Therapeutic education
• Occupational therapy
• Horticultural therapy
• Hypnosis
• Physiotherapy
• Massage lotions
• Meditation
• Music therapy
• Posturology
• Companion presence
• Psychosocial support
• Transcutaneous electrical nerve stimulation (TENS)
• Comfort therapy
• Theatre therapy
• Psychosocial therapy
• Tonification and strengthening
• Yoga

How many hopes dashed? How much time wasted? How many futile efforts? How much money squandered? How many unnecessary carbon emissions from transport? This subtly highlights pharmacological treatments and pain surgeries, which have precise contents and proven effects. The NPIS and its partners propose a solution to break this deadlock in favor of those affected by health issues. The goal is to provide reliable information on the most relevant NPI. It is also about no longer opposing pharmacological and non-pharmacological therapies, but rather associating them wisely and at the right time.

The NPIS has outlined a roadmap from 2021 to 2030 aligned with the strategies of European and international health institutions. To this end, it has initiated discussions with the European Public Health Association (EUPHA), involved in health service innovation, the European Centre for Disease Prevention and Control (ECDC), which is planning to create a registry, the European Commission, which aims to promote "health, nutrition, mental health, and psychosocial support to communities," and WHO Europe, which intends to identify the "most effective health interventions" by 2030. The NPIS submitted several European projects in 2024.

The NPIS is also engaging with WHO, which has advocated for "self-care interventions" since 2022, included NPI in its Global Action Plan for Mental Health published in 2022, and identified "the most effective and feasible interventions in a national context" in a report published in 2021. Additionally, it is collaborating with other international organizations such as UNESCO, which has promoted "specific health and well-being education interventions" since 2016, UNICEF, which has advocated for sharing "effective health interventions" since 2016 and developing "primary healthcare" since 2018, the UN, which has called for "accelerating essential health services" since 2023, and the Coalition of Partnerships for Universal Health Coverage and Global Health, advocating for "people-centered, comprehensive, and integrated services" since 2021.

Thus, an ecosystem for NPI, from research to practice through training and delivery, is being constructed, with NPIS actively participating. It involves all stakeholders, both academic and non-academic, to create a true value chain benefiting personalized and precision medicine based on science, sustainable health, and equitable longevity. With over 2.1 billion people aged over 60 by 2050, multistakeholder collaborations will be the foundation of a sustainable and equitable longevity economy.

This is why forums on NPI have been organized since 2024 in France and Europe, called NPIS Forum. An international summit titled NPIS Summit takes place every year in October, and regional events called NPIS Satellite gather professionals and users around a health theme.

Each NPI file in the NPI Registry has been submitted by a practitioner or researcher through the dedicated platform hosted by the NPIS. Each file undergoes review by an independent and integrated scientific committee. This committee invites relevant scientific societies and health authorities to validate the NPI files and/or to oversee the decisions made. Each validated file is then reviewed by a committee of users and professionals. Once labeled NPIS©, the file is translated into at least English and French and integrated into the NPI Registry.

The file contains standardized content supported by scientific studies that align with the NPIS definition of NPI, the expected specifications (Table 2), and the consensual evaluation framework for NPI, known as the NPIS Model. It includes a manual for professionals, an information notice for users, a section on funding options, and an area for anonymous user feedback. This ensures the file remains dynamic and part of a virtuous cycle of continuous improvement for the NPI.

A minimum of one prototypical study, one mechanistic study, two interventional studies, and one implementation study published in a peer-reviewed journal is required for an NPI proposal to be accepted by the expert committee tasked with validating the NPI file and awarding the NPIS© label. Specifically, experts must have evidence to anonymously vote on each criterion of the NPI file proposed to the NPIS by a submitter:

• Described (≥ 1 prototypical study)
• Explainable (≥ 1 mechanistic study)
• Effective (≥ 2 interventional studies)
• Safe (≥ 2 interventional studies)
• Implementable (≥ 1 implementation study in the country)

A professional must understand all the specifics of the NPI, the criteria justifying its use, how to implement its protocol, whom to contact, useful tips, required materials, and any prerequisite training needed.