Thoughts on evaluating Green Exercise and Our Natural Health Service

Dominic Hall, Operations Leader – Communities and Biodiversity, The Conservation Volunteers

I pride myself on being logically minded – and I am drawn instinctive to the idea of evidence led policy. The basic idea that decisions should be made based on solid, researched evidence as opposed to gut instinct, political expedience or personal agendas seems entirely compelling.

However, the more you look at what this means in practice the more complex and challenging it becomes. Policy issues are complex, multi-dimensional and multi-facetted. Robust, research evidence is difficult to produce and tends from necessity to deal with narrowed, specific research questions which can take years to answer – and more often than not raise more questions than answers.  Furthermore very often in the rare cases where a narrow researchable question can be identified – that evidence often becomes just one factor which is set against political ideology, public opinion and many other factors.

No where does this seem more challenging than in my work at The Conservation Volunteers and that of many others attempting to build the evidence required to convince policy makers to meaningfully invest in the idea of Green Exercise or the Natural Health Service.

There are lots and lots of small scale projects and many research projects which provide evidence for the many benefits of increasing activity levels, providing access to greenspaces and being in nature.  Furthermore for many people it is intuitively obvious and their own personal experience that fresh air, exercise and being in the great outdoors is good for mental and physical health.

On that basis, it might seem equally obvious that it would be valuable to invest at least some NHS money in getting more people more active and outdoors more.  But whilst most people will accept the intuitive premise, when we come to budgetary decisions people require evidence – just how effective is it? What direct savings could we make, for example in terms of reduced need for mental health treatments, or reduced burden of type 2 diabetes.  When we come to these kinds of specific questions evidence is much harder to come by.  In a medical setting we find ourselves in a system which considers hugely expensive, large sample, clinically controlled trials to be the gold standard of evidence of the kind that only large multi-national, multi-million pound pharmaceutical companies can afford to deliver or have the financial motivation to do so. The delivery agencies of green exercise are small, charitable organisations who cannot.  It is hard to build a compelling competing evidence base from small scale cohorts with limited and often amateur evaluation.

But that is only half of the problem in evidencing the value of green exercise.  It and other similar interventions are not like a drug targeting a specific disease or condition.  They are broad, community interventions.  TCV’s Green Gym programme for example brings communities together to carry out practical improvements to their local greenspaces.  Participants improve their physical activity levels with a wide range of health benefits, they get outdoors and learn new skills improving their mental health, they meet other people reducing social isolation, they build a strong sense of community, they improve the local spaces in their area giving them a sense of purpose and create better local greenspaces for all who live in that area, encouraging others to get outdoors and active more, and feel more pride in their local area and community.

Sometimes, with help from research partnerships, or through the hard work of the project officers running the projects, we may be able to assess just one of these factors. Only a few weeks ago TCV’s Green Gym featured on the TV programme “Trust me I’m a Doctor” which, in collaboration with the University of Westminster was able to show a 20% increase in cortisol response amongst Green Gym participants.  This is a brilliant result but reduces the evidence to simply one marker, in one aspect of the wide impact that programme had.  On the other end of the scale New Economics Forum has carried out a study of the Green Gym Programme which showed a Social Return on Investment (SROI) of £4.02 for every pound spent.  This looks at the wider benefits this programme provides, but conversely lacks the ability to influence any one decision maker or budget holder as no one holds a budget which is targeted at such a wide range of outcomes.

It is therefore incredibly hard to provide the right kind of evidence, at the right scale.  The standard tools available are either too broad and indistinct (like SROI) or too narrow and limited – for example WEMWEBS.  In order to really reflect the impact these kinds of programme have, we need to change the way we think of evidence and value wider community experiences.

To bring this down to practical examples:

Wild Ways Well – Cumbernauld.  TCV has developed a mental health focused programme of environmental activities, based around the New Economics Foundation Five Ways to Wellbeing.  Starting with small scale pilots – funded with pots at first of a just a few thousand pounds at a time – we have delivered a series of 6 to 12 week programmes with up to 10 participants in each.  Trying to show definitive evidence of impact on Mental wellbeing is very difficult with these numbers.  Even using the standardised mental health scores, you can only really end up with very mixed results which are not statistically significant.  And yet the feedback of participants, and more basic measures (like their continued attendance even in terrible weather!) speaks volumes of what they get out of the programme.

Hospital Greenspace Programme – working with the Green Exercise Partnership TCV has Project Officers working on three hospital sites across Scotland.  Their aim is to get more patients, staff and community members using the greenspaces for the health benefits they can provide.  One simple example of a volunteer on our New Craigs site in Inverness illustrates the challenges of evaluating this impact.  A patient in hospital with severe depression took part in the programme and found it so valuable that she credits the programme with shortening her stay in hospital considerably (compared to previous admissions).  She continues to use the programme now she has left the hospital.  As a result she was very keen to help with our evaluation efforts of the programme.  She struggled away trying to complete the standard mental health survey scores, undergoing considerable stress and anxiety in completing the form – obviously completely contrary to the purpose of the intervention.  Yet surely a more meaningful evaluation is provided by the fact that she told the project officer that her persistent sore throat – one of the key indicators of her anxiety –  had gone when she was out gardening with the group.  After all the time and stress the evaluation form caused failed to reflect this simple yet powerful story of the programmes impact.  Yet you try explaining to NHS decision makers that they must fund these kinds of programmes because you cured one patient’s sore throat and you can imagine the response!

This is why we are excited to be working with the Measuring Humanity project – to look at ways to understand and represent the far wider benefits which we see these small scale community interventions have – to bring together the breadth of experience of the participants on the programmes but also to be able to structure this in a formal and academically robust ways which enables this evidence to be influential and ultimately affect decisions about how we allocate budgets and how we design our Health Service – well that should be easy then!