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 growing 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 32 French and European scientific societies and multiple health-related institutions and research networks. 

Accessible Protocols in Consultation

• Enhanced the quality and safety of existing practices through formalization and harmonization.
• Integration of NPI into healthcare management softwares.
• Access to documentation from computers, tablets, or smartphones for ease of use.
• Quick and easy access to information at critical decision-making moments for prevention and care.
• Simplifies the follow-up and implementation of NPI (e.g., identifying barriers, professional leadership, availability of training and support).

Quality Control and Adherence to Protocols

• Improves traceability by using unique coded protocols.
• Strengthened the relationship between care givers and patients.
• Provides tools for tracking key performance indicators.
• Serves as an educational resource for ongoing professional development.
• Incorporates regular updates based on user feedback.

Means of Valuation

• Addresses problems identified by healthcare teams in a specific territory.
• Expands the roles of many professionals, particularly non-physicians.
• Phases out protocols that are ineffective, hazardous, or expensive.
• Decreases the need for multiple meetings focused on intervention planning.
• Boosting professionals' confidence to experiment new practices.
• Ensures appropriate financial and resources allocation for effective implementation.

An evidence-based data point is a theoretical or practical knowledge acquired through rigorous and integrated scientific methods and reasoning. The NPIS Model follows this logic in the health field (see Figure 3). It provides specific methodological and ethical recommendations for NPI for studies focusing on their mechanisms and explanatory processes (mechanistic study), their content (prototypical study), their evolution over time (observational study), their benefits and risks (interventional study), and their application and personalization modalities (implementation study).

Moving, eating, drinking, sleeping, talking, reading, writing, painting, listening to music, watching a movie, dancing, laughing, walking, singing, meditating, gardening, socializing, etc., are all activities of daily life. Some of these can generate joy, pleasure, personal growth, and well-being. In a democratic country, everyone is free to interpret and experience these activities in their own way. This relates to life philosophy, lifestyle, the art of living, and personal development. In other words, a daily activity is not an intervention, even if it can occasionally and randomly contribute to the health of certain individuals. Occupational activities and treatments for health problems identified by medicine are different.

The following products are not considered NPI:

• Hygiene and beauty products (shampoo, toothpaste, brush, body cream, etc.)
• Natural products (plants, food, mushrooms, essential oils, etc.)
• Health products (medications, implantable biological materials, dietary supplements, etc.)
• Medical devices (artificial organs, prosthetics, orthotics, digital applications, monitoring systems, etc.)

The following goods and services are not considered NPI:

• Cultural products or services (video games, books, podcasts, artistic practices, museum visits, theater, writing, etc.)
• Everyday consumer products or services (haircuts, aesthetic treatments, dining out, etc.)

The following actions are not considered NPI:

• Public health promotion activities (communication campaigns, videos, posters, booklets, websites, social media posts, etc.)
• Architectural adaptations (creating access ramps, etc.)
• Environmental adaptations (reforestation of a park, creation of a sports workshop, etc.)

The following approaches are not considered NPI:

• Professional disciplines (physiotherapy, psychology, dietetics, public health, etc.)
• Educational approaches (personal development, etc.)
• Esoteric practices (spiritual practices, religious worship, divination, witchcraft, etc.)

The following organizations are not considered NPI :

• Health organizations (networks, platforms, clinics, health centers, healthcare establishments, etc.)
• Health systems (digital platforms, etc.)

The following measures are not considered NPI :

• Health policies (strategies, plans, programs, etc.)
• Regulations (decrees, laws, etc.)
• Judicial decisions (warnings, convictions, etc.)

A scientific validation model for medications has existed since the 1960s, with specific regulations recognized worldwide (e.g., FDA, EMA, ANSM). A similar procedure has recently been implemented for medical devices in Europe. However, until now, no consensual model existed for nutritional, bodily, and psychosocial health services due to confusions between approach, protocol, and technique/ingredient. A participatory, pragmatic, and multidisciplinary consensus work followed international scientific health recommendations to address this for NPI (Ninot et al., 2023).

This work took into account the specificities of NPI, health risks, the balance between internal and external validity, the justification of explanatory mechanisms, ethical considerations in health, and respect for contexts of use. The NPIS Model accelerates research through the harmonization of methodological and ethical expectations in NPI. It also enhances the identification, referencing, transferability, and implementation of NPI for the benefit of user health and safety, improving the quality of training.

Ultimately, the NPIS Model distinguishes between individualized, science-based services aimed at addressing known health issues in Western medicine and occupational practices (lifestyle, art of living, work, sociocultural activity, personal development, pursuit of happiness, spiritual practice, etc.). In this sense, the model does not impede individuals' freedom to choose a particular lifestyle. It aims to address a specific health issue for an individual or a group of people within a limited timeframe and a framework regulated by the health sector. The NPIS Model encourages innovations across all other health sectors, particularly in health organizations and early identification actions for health problems.

The choice and implementation of an NPI at a given moment in a person's prevention and care journey do not depend on the NPI Registry, nor on the mission of the NPIS. These decisions are influenced by individual health situations, preferences, the availability of professionals, the qualifications of practitioners, accessibility in a given area, and socio-cultural contexts. The art of combining NPI with each other and with other health solutions at the right time lies with professionals, expert systems, interdisciplinary organizations, and the healthcare system in place in a specific country. The NPI Registry highlights essential practices that have proven effective and continue to evolve through research and feedback analysis. The NPIS has no authority to impose a choice of NPI. Each professional is free to follow them, to pursue others, or to create new ones. The same applies to each healthcare organization.