Nature-based interventions, often abbreviated as NBIs, have proliferated in recent years as policymakers and communities grapple with the twin crises of mental ill-health and environmental degradation. These programmes range from structured green prescriptions issued by health services to participatory science initiatives and community gardening schemes. Despite their wildly different formats, most share two common ambitions: promoting psychological wellbeing and strengthening what researchers call nature connectedness, the subjective sense of closeness to the natural world. Yet the sector has been repeatedly criticised for lacking a consistent evidence base, because countless projects evaluate themselves with different methods shaped by individual funder requirements, producing scattered datasets that cannot be compared, combined, or analysed with any statistical power.

The new study, led by Michael L. Lengieza of Durham University together with Elizabeth Richardson of Natural England and Miles Richardson of the University of Derby, tackles this fragmentation head-on. The team presents a centralised evaluation tool, developed by Natural England, that allows individual projects to administer a standardised survey, enter key features of their programme, and feed participant data into a shared dashboard. Larger organisations gain the ability to combine data across many initiatives, while smaller organisations, which often lack the expertise to design their own evaluations, receive a ready-made solution that removes the burden of survey design, ethics applications, and basic analysis.

As a proof of concept, the researchers pooled data from 75 members of the public who participated in one of eight real-world nature projects and completed both baseline and follow-up surveys. Nature connectedness was measured using an adapted version of the inclusion of nature in self scale alongside the statement-based item measuring how much people feel part of nature, while wellbeing was captured with the Office for National Statistics personal wellbeing questions. Project coordinators also completed a survey describing their programme’s features, including whether they used a recognised delivery framework such as the pathways to nature connectedness.

The results were striking. Using multi-level statistical models with random intercepts for both participants and projects, the team found that nature connectedness increased significantly between the start and end of the programmes across all eight initiatives. But the more revealing discovery emerged when the researchers tested whether the size of that increase depended on programme characteristics. Projects that explicitly employed the pathways to nature connectedness framework, which identifies five routes to connection through sensory contact, emotion, beauty, meaning, and compassion, showed a robust and statistically significant rise in participants’ nature connectedness. Projects that did not use the framework showed only a small, non-significant change, suggesting they might not have been effective at all.

Crucially, the analysis showed that pathways-based and non-pathways-based projects attracted participants with similar baseline levels of nature connectedness, meaning the difference in outcomes could not be explained by one type of programme simply recruiting more devoted nature lovers. The type of engagement, not the type of audience, appeared to make the difference. This pattern aligns closely with the existing academic literature, which has repeatedly shown that actively noticing nature, attending to its beauty, and engaging the senses produce stronger gains than mere time spent outdoors. Analysing any single one of the eight projects in isolation would have been statistically impossible; only the pooled data made the comparison feasible.

The authors are careful to stress what the data cannot show. Because the study lacked experimental control, causality cannot be established. People who seek out nature-connection programmes might be making other lifestyle changes that drive the effect, and programmes using the pathways framework might simply be more enthusiastic or rigorous in ways that matter more than the framework itself. Nevertheless, the researchers note that pre-post time-series designs have a long and respected history in public health evaluation, and that the absence of a change would have more definitively ruled out a causal link. The observed increase, combined with the moderation by framework type, signals exactly where the sector should direct its next wave of controlled experiments and its resources.

The study also offers practical guidance for scaling the approach. Data must include at least one baseline and one follow-up measurement, ideally collected at similar intervals relative to each project’s start and end. Because crowdsourced data will inevitably be noisier than laboratory data, larger samples are essential, and null effects should be interpreted with caution since they may reflect insufficient statistical power rather than a true absence of effect. The tool’s live dashboard, built on Power BI, already gives project managers simple benchmarked summaries of their own performance against the sector, while allowing policymakers and funders to view aggregated results and export datasets for formal analysis.

Looking ahead, the authors envision a modular future for the tool, with optional modules capturing additional outcomes such as physical activity and loneliness, demographic variables, and psychological factors like mindfulness and emotion. They also argue that national and regional bodies, including environmental funders, should move beyond publishing evaluation frameworks and instead provide practical tools that support reporting and data combination. By reducing the evaluation burden on small organisations, the approach frees resources for delivery while building the scalable, policy-relevant evidence base that nature-based interventions need to influence decision-makers at national and international levels, from the Dasgupta Review to the Kunming-Montreal global biodiversity framework.

For a sector long dismissed as fragmented and under-evidenced, the message of this proof of concept is quietly transformative: the collective data of many small initiatives, pooled intelligently, can illuminate what works, guide investment, and ultimately amplify the social and ecological benefits of humanity’s reconnection with nature.

Subject of Research: Crowdsourced evaluation of nature-based interventions using pooled nature connectedness and wellbeing data

Article Title: Amplifying social benefits from multiple nature-based initiatives by crowdsourcing nature connectedness and wellbeing data: A proof of concept

Article References: Lengieza, M. L., Richardson, E., & Richardson, M. (2026). Amplifying social benefits from multiple nature-based initiatives by crowdsourcing nature connectedness and wellbeing data: A proof of concept. Ambio. https://doi.org/10.1007/s13280-026-02472-1

Image Credits: AI Generated

DOI: 10.1007/s13280-026-02472-1

Keywords: nature connectedness, nature-based interventions, crowdsourcing, programme evaluation, wellbeing, pathways to nature connectedness, Natural England, green prescriptions, environmental psychology, evidence-based practice, biodiversity policy, public health