Enhancing Health Through Access to Nature: How Effective are Interventions in Woodlands in Deprived Urban Communities? A Quasi-experimental Study in Scotland, UK

Round 1

Reviewer 1 Report

Enhancing health through access to nature: how effective are interventions in woodlands in deprived urban communities? A quasi-experimental study in Scotland, UK

Catharine Ward Thompson 1 *, Aldo Elizalde 2, , Steven Cummins 3, Alastair H Leyland 4, Willings 6 Botha 5, Andrew Briggs 6, Sara Tilley 1, Eva Silveirinha de Oliveira 8, Jenny Roe 9, Peter Aspinall 10 and Richard Mitchell 11

The paper raises an urgent issue of taking care of the mental health and the need for decreasing the stress levels among society members. Taking advantage of natural environment is likely to mitigate stress and enhance mental health.

It is the first study that makes an attempt to find evidence for the positive effect  of green spaces and forestry interventions to improve health in urban communities (especially the deprived ones), taking into account their influence on increased nature connectedness and social cohesion, which could reduce challenges for healthcare provision. These actions are expected to help integrate health issues into spatial and urban landscape by supporting government policy-makers, local communities and nongovernmental organizations in taking care of community health and wellbeing.
Positive association between mental health and access to nature has been confirmed, however the impact of interventions involving physical change to the environment is less clear.

The Authors raise a question of how to design environmental intervention that would encourage the local community to take advantage of green spaces, physical activity and psychological connection with nature, which could all enhance community cohesion.

The study used mixed methods involving environmental audits by trained auditors and local community members. Stress levels were measured using the Perceived Stress Scale (PSS). Health-related quality of life was measured using the self-report EuroQol measure (EQ-5D). Physical activity (PA) was measured using the International Physical Activity Questionnaire 212 short form (IPAQ-SF).Nature visits were measured by asking if participants had visited the local woods (target of 219 study) or other local parks or green spaces in the last 12 months (yes/no). Emotional connection to the natural world (connectedness with nature) was measured using 224 the Inclusion of Nature in Self Scale. Social cohesion was measured based on three items from the English Citizenship Survey 227 covering trust of neighbours, neighbourhood belonging, and whether people in the 228 neighbourhood pull together to improve things.

The cost-consequences analysis and complete case analysis were also performed.

The tools were chosen adequately and the research was conducted with great care and accuracy.

The Authors took an effort to gather a lot of data regarding the described interventions. The results are presented comprehensively and the conclusions cover a broad approach to the issue.

It was found that stress levels within communities also reflected influences external to the intervention programme. The Authors admit that “the interventions were insufficient to negate these likely other influences”.

Although not all questions were clearly answered, the innovative approach of the study involves drawing attention to the need for including health issues in landscape planning, which is of great value and importance.

Author Response

We thank the reviewer for the recognition of the innovative and comprehensive nature of the study and careful reporting of results. We have added a summary figure (Figure 6) in an attempt to clarify the findings.

Reviewer 2 Report

Sustainability is a very good outlet for this paper which itself is very good. This paper covers many aspects of the potential benefits of providing better access to nature to disadvantaged communities for their health and quality of life.  The study takes place in Scotland and documents in great details the impact of some woodland improvement.

  The study covers the years 2012 to 2014, which is already too small to be able to make any precise assessment of the health effect. For that kind of study one needs a large cohort over many years. Furthermore the “baseline” 2012 is more a reference as it is not as well documented as the rest.

  Having said that, a lot of data (in that “semi-empirical” study) the rest of the period have been gathered. The authors make a very good job at detailing how they proceeded. This part of the study can easily serve as template to the many studies that one hopes will follow. To get a general judgment to what the potential impact of such woodland projects may be, one has to make his way in a jungle of many issues.

  One is whether the woodland projects were as good as they could have been. How to optimize their cost efficiency and impact on the local community.

   The cohort of people followed is divided along several criteria (age, gender and also economic and a variety of social criteria). That potentially makes the analysis complicated to conduct and understand. There are also geographical considerations: distance to the woodlands for example.

   As far as impact goes, the authors rely a lot on PSS (Perceived Stress Scale), which is as good a measure of stress as exists, but still not ultimately precise. The authors use quite a few other indicators to estimate the Quality of Life and how it has been impacted in the short period of the study. They use the so-called “Quality Adjusted Life Year (QALY) and estimate whether it changed during the period as a result of the establishment of new woodland projects.

  I think that they are a bit miser of information on how exactly QALY is calculated, what are the typical numbers and how to interpret them. But they do not conceal that the outcome is not so clear-cut as there were additional external factors, which changed the life conditions of the people under study.

They also frame the problem of how to maximize the impact of these projects taking into account their physical activity and how it could be affected. In other words, the reader is confronted to a jungle of issues.

Nothing is simple…

  The cost estimates could also have been made more transparent. The costs of the WIAT (Woods In and Around Towns) are easily understood. The cost per person also is easily understood, but when it comes to the “cost per QALY”, the analysis is more opaque.

    Having said that I think this paper (which in fact is a summary of the results of a much larger report) is largely above the threshold of acceptability for publication in Sustainability.

Author Response

We thank the reviewer for the recognition of the quality of the study, despite the limitations in terms of timeframe, etc., which we have acknowledged. We also thank the reviewer for recognising the value of the study design as a potential template for future studies.

In order to clarify the economic analyses, we have added a fuller explanation of the cost utility analysis (CUA) and how this relates to Health-Related Quality of Life via Quality Adjusted Life Years (QALYs) in lines 440-459. We have also added references here and in Appendix A to the full study report to assist with understanding.

In order to help understand the “jungle of issues”, we have made a few edits to the paper and added a summary figure (Figure 6) in an attempt to clarify the key outcomes. We believe this assists with an overview of what is, inevitably, a complex study.