Seeing the Forest and the Trees: Protocol for a Qualitative Systematic Review and Metasynthesis on Forest- and Nature-based Therapies in Greenspaces to Improve Health and Well-Being of Adult Participants

Abstract

Background: Systematic reviews and metanalyses of randomized controlled trials (RCTs) have provided robust evidence on the health benefits of nature-based therapies in greenspaces. While such approaches are indispensable for advancing knowledge on therapeutic effects, they do not adequately capture the contextual and interpretive dimensions around these interventions. In the field of Traditional, Complementary, and Integrative Medicine (TCIM), patient perspectives, meaning and decision-making processes, as well as complex interactions play a pivotal role. Despite this, they remain insufficiently researched. To bridge this gap, we conduct a metasynthesis of qualitative studies on nature therapies. This synthesis seeks to complement quantitative findings by offering in-depth insights into participants’ lived experiences and the multifaceted subjective effects of these interventions. The metasynthesis is guided by the following research questions: (1) How do nature-based therapies affect the health and well-being of participants? (2) How do participants in nature-based therapies experience and interact with nature and what is relevant to them? Methods: The metasynthesis follows a systematic approach based on the methodological framework developed by Sandelowski and colleagues, comprising of six sequential phases: (1) conceptualization of the qualitative research design, (2) execution of a comprehensive and systematic literature search with subsequent study selection, (3) classification of the findings, (4) synthesis and integration of qualitative findings, (5) assurance of methodological rigor, and (6) transparent reporting of the outcomes. The systematic search for qualitative studies of interest will be carried out using three databases of particular relevance to the research topic: CINAHL (EBSCO), MEDLINE (PubMed, Ovid), and Embase (Ovid). All stages of the process, from phase one through phase six, will be conducted collaboratively by at least two researchers. The protocol is structured in accordance with PRISMA-P guidelines, and the reporting of the metasynthesis will follow the ENTREQ parameters.

Keywords

protocol systematic review metasynthesis nature therapy forest therapy forest bathing green spaces

Background

The ages-old human practice of finding respite in nature spans across cultures and biospheres in an increasingly built and urban world (World Health Organization (WHO), 2016). Altered and minimized access to natural landscapes coexists with a complex panoply of stressors and conditions that mitigate human health. Whether termed forest bathing, spending time or moving through nature or naturally greenspace, gardening and working with plants, natural landscapes are thought to have an important effect on human development and psychology through the Biophilia hypothesis (Kahn Jr., 1997; Kaplan, 1995; Ulrich et al., 1991). Across the human lifecycle, demographics and health problems, the benefits of spending time in greenspace have been demonstrated in countless systematic reviews to have broad application for human health across demographic groups (Bettmann et al., 2025; Bray et al., 2022; Clark et al., 2023; Gascon et al., 2016; Geneshka et al., 2021; Marcham & Ellett, 2024; Nejade et al., 2022; Nguyen et al., 2023; van den Berg et al., 2015; van den Bosch & Ode Sang, 2017). While there is an ever-expanding foundation of evidence on which the health benefits of spending time in natural settings benefits the health and well-being of humans, nuances of these findings still obfuscate broad and blanket application and implementation. Part of the difficulty with creating a one-size-fits-all policy and approach to advocate for time spent in greenspaces lies in the heterogeneous nature of natural settings as well as the breadth of interventions for their time spent and use.

This withstanding, the study of the effects of nature on individuals and groups has been thoroughly examined. While the focus of the scientific gaze trends naturally to the gold standard of the randomized control trial, including on the topic of nature-based therapy in greenspaces and forest therapy (Gobster et al., 2022), the individual and subjective effect of nature on humans is complex. For this reason, the qualitative subjective examination to gain insights regarding the needs, circumstances and health phenomena of specific demographics of people is essential. The qualitative studies on the topic include different methodological approaches, such as focus group discussions, interviews, and participant observation in different settings and focused on various target groups (Gobster et al., 2022). To shed light on the complexity of how people experience nature-based interventions, an integration of qualitative insights is needed for a holistic view - to see the forest for the trees.

To consolidate and aggregate the nuanced subjective findings of qualitative research delineated by time, natural place, demographic and health condition, a synthesis of qualitative research will be conducted. The methodological approach chosen is a metasynthesis for qualitative studies, which is a systematic review that can be described as a counterpart and complement to that of quantitative research. The concept of metasynthesis does not imply the use of a particular method but offers a theoretical review framework (“a methodological toolbox” (Sandelowski & Barroso, 2007: xv)) in which the systematic approach and the focus on qualitative research are predetermined. In accordance, Sandelowski and Barroso describe a metasynthesis as an approach that systematically interprets the collection and analysis (Sandelowski & Barroso, 2003b) of qualitative studies by using qualitative methods to synthesize findings (Lindahl et al., 2011). A metasynthesis is seen as “an interpretive integration of qualitative findings in primary research” (Sandelowski & Barroso, 2007, p. 199), in which the “integration of findings […] is more than the sum of the parts” (Thorne et al., 2004). Such rich contributions to meta-level qualitative research can be described as “a goldmine for evidence-based practice” (Ludvigsen et al., 2016). A metasynthesis provides a framework to draw comparison of study characteristics, such as design, keywords, country of origin, population, and location. At the same time, using the constant comparison method found in grounded theory (Charmaz, 2014; Strauss & Corbin, 1997), a meta-level of analysis is allowed to bubble to the surface (Paterson et al., 2009). Hence, a metasynthesis is best-suited to analyzing and integrating qualitative findings about the complex nature of the impact of greenspace nature therapies on human health and well-being (Dawson, 2019; Sandelowski & Barroso, 2002, 2003a; Sandelowski et al., 1997). The complex internal experience of individuals spending time in natural, green settings, including their emic perspectives, may thereby be captured in the analysis and synthesis of qualitative research.

Objectives

Against this background, the objective of the metasynthesis is to deepen, broaden, and complement the existing quantitative evidence on the effectiveness of nature therapies in greenspaces for health promotion in adult participants by synthesizing and interpreting the findings of qualitative research on this topic. The findings of the metasynthesis aim to support and guide the further adaptation and development of research and practical implementation within the field of nature therapies, considering the complexity of nature-based interventions in their subjective, detailed, and also unexpected effects.

Methods

Study Design

To transform the research findings from qualitative primary studies on the nature experiences of participants into research syntheses – in accordance with the research objective and the underlying research questions – a metasynthesis will be conducted. The metasynthesis will integrate both the methodological considerations proposed by Sandelowski et al. (Ludvigsen et al., 2016; Sandelowski, 2012; Sandelowski & Barroso, 2002, 2007; Sandelowski et al., 1997) and the guidance of the Cochrane-Campbell Handbook for Qualitative Evidence Synthesis into its framework, ensuring a rigorous and structured approach to the synthesis process. The steps of the research process will include: (1) conceptualizing the qualitative research study design (defining the research purpose, objective and questions), (2) conducting an appropriate systematic literature search, identifying, and selecting relevant studies, (3) classifying findings, (4) integrating qualitative findings, (5) ensuring methodological rigor, and (6) presenting the results (Sandelowski & Barroso, 2007).

Research Question

The metasynthesis process will be guided by the following research questions: (1) How do nature-based therapies affect the health and well-being of participants? (2) How do participants in nature-based therapies experience and interact with nature and what is relevant to them?

The research questions follow the Cochrane guidance (Booth A et al., Draft version (November 2024)) and are intentionally designed to be broad, in order to incorporate potentially relevant and even unexpected findings from the included primary studies into the metasynthesis.

Eligibility Criteria

Based on the SPIDER framework (Cooke et al., 2012) that is preferential and adapted to qualitative research questions, we differentiate our research interest in Sample, Phenomenon of Interest, Design, Evaluation, and Research type. The description of each category leads to (a) our inclusion criteria for the search strategy and (b) a list of relevant search terms (see table 1). In accordance, we intend to include primary studies that contain a qualitative research component – these can be qualitative studies or mixed-methods studies with a qualitative research part. Topically, the focus will be on nature-based health interventions in greenspaces such as gardening, forest therapy, and forest bathing. The underlying research designs and theoretical underpinnings might be guided by the background of phenomenology, grounded theory, or ethnography. The region and setting will remain intentionally broad in order not to lose any potentially relevant studies in which the intervention takes place. Subsequently, we intend to comprehensively include all studies that correspond to the descriptive characteristics. Depending on the number of studies included after the first systematic search, we may undertake a purposive sampling approach (Schreier, 2018), which is common in qualitative research and can also be conducted in the context of a metasynthesis (Sandelowski, 2012). We will exclude studies that do not meet the inclusion criteria. No restrictions will be imposed on the publication date and language in order to ensure that all potentially relevant studies, regardless of their time of publication, will be included in the search process.

Table 1.

Framework SPIDER

	Description	Search terms
Sample	Adult participants	---
Phenomenon of interest	Health related nature-based interventions, e.g. greenspaces, forest bathing, gardening (…)	Forest bathing, shinrin-yoku, greenspace, nature-based intervention, green intervention, forest therap, nature therap, garden, horticult*
Design	Qualitative research designs	--- (under “research type”)
Evaluation	Experiences with, opinions about, perceptions of nature	--- (under “research type”)
Research type	Empirical primary qualitative and mixed-methods studies	Qualitative research, qualitative method, mixed-method, ethnography grounded theory, phenomenology

Information Sources and Search Strategy

We adapted the search strategy for all databases used (CINAHL (EBSCO), MEDLINE (PubMed, Ovid), and Embase (Ovid)). The databases have been selected based on their relevance to the research topic. The search strategy is based on the search terms developed in consideration of the SPIDER criteria (see table 1) and further defined with the help of the tools Yale MeSH Analyzer, MESH on Demand, and MESH-Browser. We have combined the search terms using the Boolean operators AND/OR and used the title/abstract restrictions to limit the search in a meaningful way. An initial test run was conducted in August 2024. The search strategy led to 640 publications (MEDLINE = 169, EMBASE = 372, CINAHL = 99). The search strategy will be repeated for the metasynthesis. In addition, a reference and a foodnote check will be carried out for all included studies in order to identify any further relevant studies (in orientation on TARCiS1 (Hirt et al., 2024) and Sandelowski & Barroso (2007)).

Data Management

Once the searches have been completed, all found publications will be imported into the Systematic Review Facility (SyRF).2 We plan to use the SyRF for the joint selection process of the publications found according to the search strategy and for the quality appraisal of the subsequently included studies. The process will consist of the following steps: First, the studies will be filtered for duplicates, and duplicates will be deleted. At least two researchers [JC, SB] will independently screen the titles and abstracts for inclusion, and in case of disagreement about inclusion, a discussion will resolve discrepancies. A third author [WS] will be involved in the discussion. All primary studies included after the first screening cycle will be reviewed in full by both researchers [JC, SB]. If needed, translation software will be used to translate papers into English or German (DeepL Pro Ultimate, Version 24.11.4). Reasons for exclusion will be documented. The full-text articles that were finally included will then be imported into the software MAXQDA24³ for further processing.

Critical Appraisal

To systematically analyze and increase the rigor of the metasynthesis’ findings (Small, 2023) a quality assessment of the primary qualitive studies will take place. The selection of the appropriate quality appraisal tool will be discussed and decided by SB and JC on the basis of the article “Appraising Qualitative Research for Evidence Syntheses: A Compendium of Quality Appraisal Tools” (Majid & Vanstone, 2018). In order to avoid losing potentially relevant studies due to low methodological quality, we aim to use the results of the quality appraisal not to exclude papers, but to enhance transparency regarding the quality classification of the included studies. We are thus following the approach of Sandelowski (2012), who argues: “Quality criteria are, therefore, most wisely used in qualitative metasynthesis projects, not to exclude reports or findings a priori, but rather to characterize them for use in a posteriori analyses” (ibid.: 22).

Data Extraction

We consider the most relevant part of data extraction to decide which part/s of the primary studies are to be indicated as our data set according to the research objectives and questions. Our decision making is guided by the indications of Sandelowski (2012), who specifies that the data set used for the qualitative metasynthesis is based on the findings of the included primary qualitative studies: “[…] qualitative metasynthesis is targeted […] toward one element in that report (the findings) […]” (Sandelowski, 2012, p. 20). In order to extract the findings from the included qualitative primary studies that will be the data set for further analysis in metasyntheses, some preliminary factors are taken into consideration. Sandelowski (2012) emphasizes the distinction between the original primary data on which the included studies are based, and the data used for the metasynthesis: “Qualitative metasyntheses are composed of reviewers’ interpretation of researchers’ interpretations of their data, not of those data themselves” (ibid.: 20). This approach might also include interpretations of findings, such as grounded theories, phenomenological descriptions, ethnographic explanations, and other analyses that the researchers built on the basis of the primary data (Sandelowski, 2012). Therefore, the data set for our metasynthesis will consist of the findings that have been produced by the analysis and interpretation of primary data, described in the included publications that answer how nature-based therapies affect the health and well-being of participants and their experience and interactions with them.

The research team will consider the typical hurdles or pitfalls to the process of identifying findings, as described by Sandelowski & Barroso: misrepresentation of data as findings, misrepresentation of analysis as findings, misuse of quotes and incidents, the problem of theme and pattern, and/or conceptual confusion and drift (2002: 216ff). Arguments for including findings for further analysis in the metasynthesis will be made with transparent and strategic arguments. Specifically, the extraction process to reach our findings will be approached through a three-step analysis process as follows:

To describe the context of the included studies in a first step an a priori framework with a set of deductive categories will be developed in orientation on the approach of a Framework Synthesis (Barnett-Page & Thomas, 2009). The data extraction process will be conducted as outlined by Sandelowski and Barroso (2002): contextual and methodological information from the included studies will be gathered using an a priori created data extraction table. This table will include details on the publication context (authors, year of publication, journal), the intervention context (brief description of the intervention, intervention period, study duration, settings, target group, classification of the underlying therapeutic approach), and the methodological context (study design). Additionally, the data extraction table will capture the quality assessment of the study. The data extraction table will be independently pilot-tested by at least two researchers [SB, JC] on at least three included studies. The results will be discussed collaboratively, and the extraction form will be adjusted accordingly, if necessary.

The second step involves extracting the qualitative findings of the included studies that are relevant to the research objective and questions. In order to include all potentially relevant findings, all content that refers to findings and interpretation of findings will be included. These are likely to be sections of the respective publication such as the abstract, results chapter, discussion chapter and conclusion.

A third step to classify the extracted findings in order to use this as a basis for choosing the data analysis method accordingly will be conducted (Sandelowski, 2012; Sandelowski & Barroso, 2007). Sandelowski distinguishes between “findings at the data-near end of the data transformation continuum” and “findings on the data-far end of the continuum” (9: 28). Findings at the near-end indicates the level of proximity of the results with respect to the primary data. Whereas higher the level of abstraction reaching further from the data itself towards a meta-level is described as the far-end data, for example towards a grounded theory approach (Strauss & Corbin, 1997). For the first case, an aggregation of the results in the form of a metasummary is proposed. A corresponding methodological approach could be, for example, a qualitative content analysis. For the second case, or a mixture of both cases, a more open, interpretative approach is recommended, for example a grounded theory approach (Strauss & Corbin, 1997).

Data Analysis

Our data analysis intends to synthesize the findings of the included qualitative primary studies. Following the quote of Sandelowski (2012): “In qualitative metasynthesis studies, themes are discerned and metaphors and concepts are translated into each other”, the researchers will start the analysis by becoming familiar with the data to get a first impression about themes and concepts. At this point, a decision will be made regarding the further procedure, depending on the nature of the findings (near-end vs. far-end data). If only near-end data is involved, which is not to be anticipated, we will generate a metasummary instead of the planned metasynthesis. In this scenario, the data would be analyzed according to an inductive qualitative content analysis (Mayring, 2019; Schreier, 2014). In the case of far-end data or a mixture of different types of data, which is to be expected, the data analysis will follow a procedure, led by grounded theory coding principles (Strauss & Corbin, 1990, 1997): In the first step, two researchers [JC, SB] examine the data and categorize them inductively into thematic categories (open coding). During the axial coding process, the identified themes are contrasted and relationships between categories are established to reveal underlying patterns and structures. This step helps to systematically link categories by analyzing conditions, contexts and consequences. In the final step, selective coding, core categories are derived from the category system. The data are then restructured and interpreted from the perspective of the identified core category/categories.

Reporting of Protocol and Systematic Review

For the structural framework of the protocol we followed the PRISMA-P guideline (Moher et al., 2015). We will report our metasynthesis according to the reporting guideline of ENTREQ (Tong et al., 2012) to enhance transparency about our research decisions. The metasynthesis project is registered in PROSPERO under the title “Seeing the forest for the trees: a qualitative systematic review and metasynthesis on forest- and nature-based therapies in greenspaces to improve health and well-being of adult participants” and the registration number CRD420251134237.

Research Team and Reflexivity

Although this protocol was written in advance of the actual conduction of the metasynthesis, it is not to be understood as a stagnate outline. In the spirit of an iterative, open, and flexible qualitative research approach, this protocol should serve as a guideline that can be flexibly and strategically adapted to the qualitative study content and findings. Deviations from the protocol will be transparently reasoned and explained in the metasynthesis. Sandelowski (2012) references the flexible nature of qualitative research questions that takes the possibility (and opportunities) of adaptation within the framework of an iterative research process with the metaphor of a compass versus a fixed anchor. In this respect, the present protocol should be understood as a research-guiding compass. A flexible approach to research requires continuous reflection on the research process at all stages (Sandelowski & Barroso, 2007). The following steps to promote reflexivity in the research process will guide the implementation of the metasynthesis: All steps will be discussed, consented and conducted by at least two qualitative experts throughout [JC, SB] and discussed with at least one further expert of qualitative methods [WS]. Interim results and the methodological structure of the metasynthesis will be presented and discussed in a qualitative research working group with interprofessional qualitative experts (expert peer review) (Sandelowski & Barroso, 2007). There will also be a regular dialogue with the authors of a recent metaanalysis on the topic of greenspaces, nature therapies and health, entitled “Effects of greenspace interventions on mental disorders - a systematic review and meta-analysis” (Blakeslee et al., 2025), which is currently under review.

Assessment of Confidence in Review Findings-

We will report our metasynthesis according to the reporting guideline of ENTREQ (Tong et al., 2012) to enhance transparency about our research decisions.

Footnotes

Author Note

*Blakeslee SB, Koch AK, Schröter M, Jeitler M, Schepanski S, Boujnah H, Brunnhuber S, Mudu P, Forastiere F, Michalsen A, Seifert G, Kessler C. Effects of greenspace interventions on mental disorders - a systematic review and meta-analysis (submitted). 2025.

Acknowledgement

We would like to express our sincere gratitude to the author team of the meta-analysis “Effects of greenspace interventions on mental disorders - a systematic review and meta-analysis”* for the fruitful discussions and valuable insights on the topic. Their contributions greatly enriched our understanding and development of this protocol.

ORCID iD

Judith Czakert

Ethical Consideration

Our body of data will consist exclusively of already published analyses and interpretations of the primary data of the studies included in our review such as the findings. If approval of ethical standards was required for the collection of the primary data, this will have been obtained from the responsible research team and is documented in the corresponding publications. Should we notice any discrepancies in the record, we will list this in our review.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The metasynthesis is funded by the Carstens Stiftung (KVC 0/165/2025) ()

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Registration International Prospective Register of Systematic Reviews

Registration number: CRD420251134237.

Notes

References

Barnett-Page

Thomas

(2009). Methods for the synthesis of qualitative research: A critical review. BMC Medical Research Methodology, 9, 59. https://doi.org/10.1186/1471-2288-9-59

Bettmann

J. E.

Speelman

Jolley

Casucci

(2025). A systematic review and meta-analysis on the effect of nature exposure dose on adults with mental illness. Behavioral Sciences, 15(2), 153. https://doi.org/10.3390/bs15020153

Blakeslee

S. B.

Koch

A. K.

Schröter

Jeitler

Schepanski

Boujnah

Brunnhuber

Mudu

Forastiere

Michalsen

Seifert

Kessler

(2025). Effects of greenspace interventions on mental disorders - A systematic review and meta-analysis (submitted).

Booth A

N. J.

Flemming

Thomas

(Draft version (November 2024)). Chapter 2 - Defining the scope and formulating review questions. In Noyes J

H. A.

, (Ed.), Cochrane-campbell handbook for qualitative evidence synthesis (Vol. Version 1.). Cochrane.

Bray

Reece

Sinnett

Martin

Hayward

(2022). Exploring the role of exposure to green and blue spaces in preventing anxiety and depression among young people aged 14-24 years living in urban settings: A systematic review and conceptual framework. Environmental Research, 214(Pt 4), Article 114081. https://doi.org/10.1016/j.envres.2022.114081

Charmaz

(2014). Constructing grounded theory. Sage.

Clark

Vanclay

Brymer

(2023). Forest features and mental health and wellbeing: A scoping review. Journal of Environmental Psychology, 89, Article 102040. https://doi.org/10.1016/j.jenvp.2023.102040

Cooke

Smith

Booth

(2012). Beyond PICO: The SPIDER tool for qualitative evidence synthesis. Qualitative Health Research, 22(10), 1435–1443. https://doi.org/10.1177/1049732312452938

Dawson

A. J.

(2019). Meta-synthesis of qualitative research. In Liamputtong

(Ed.), Handbook of research methods in health social sciences (pp. 785–804): Springer. https://doi.org/10.1007/978-981-10-5251-4_112

10.

Gascon

Triguero-Mas

Martínez

Dadvand

Rojas-Rueda

Plasència

Nieuwenhuijsen

M. J.

(2016). Residential green spaces and mortality: A systematic review. Environment International, 86, 60–67. https://doi.org/10.1016/j.envint.2015.10.013

11.

Geneshka

Coventry

Cruz

Gilbody

(2021). Relationship between green and blue spaces with mental and physical health: A systematic review of longitudinal observational studies. International Journal of Environmental Research and Public Health, 18(17), 9010. https://doi.org/10.3390/ijerph18179010

12.

Gobster

P. H.

Schultz

C. L.

Kruger

L. E.

Henderson

J. R.

(2022). Forest therapy trails: A conceptual framework and scoping review of research. Forests, 13(10), 1613. https://doi.org/10.3390/f13101613

13.

Hirt

Nordhausen

Fuerst

Ewald

, Appenzeller-Herzog C.TARCiS study group. (2024). Guidance on terminology, application, and reporting of citation searching: The TARCiS statement. Bmj, 385, Article e078384. https://doi.org/10.1136/bmj-2023-078384

14.

Kahn

Jr, P. H.

(1997). Developmental psychology and the biophilia hypothesis: Children's affiliation with nature. Developmental Review, 17(1), 1–61. https://doi.org/10.1006/drev.1996.0430

15.

Kaplan

(1995). The restorative benefits of nature: Toward an integrative framework. Journal of Environmental Psychology, 15(3), 169–182. https://doi.org/10.1016/0272-4944(95)90001-2

16.

Lindahl

Liden

Lindblad

B. M.

(2011). A meta-synthesis describing the relationships between patients, informal caregivers and health professionals in home-care settings. Journal of Clinical Nursing, 20(3-4), 454–463. https://doi.org/10.1111/j.1365-2702.2009.03008.x

17.

Ludvigsen

M. S.

Hall

E. O. C.

Meyer

Fegran

Aagaard

Uhrenfeldt

(2016). Using sandelowski and Barroso’s meta-synthesis method in advancing qualitative evidence. Qualitative Health Research, 26(3), 320–329. https://doi.org/10.1177/1049732315576493

18.

Majid

Vanstone

(2018). Appraising qualitative research for evidence syntheses: A compendium of quality appraisal tools. Qualitative Health Research, 28(13), 2115–2131. https://doi.org/10.1177/1049732318785358

19.

Marcham

Ellett

(2024). Exposure to green spaces and schizophrenia: A systematic review. Psychological Medicine, 54(12), 1–12. https://doi.org/10.1017/s0033291724001533

20.

Mayring

(2019). Qualitative Content analysis: Demarcation, varieties, developments (1438-5627) [qualitative content analysis; text analysis; CAQDAS; qualitative research; method comparison]. https://doi.org/10.17169/fqs-20.3.3343

21.

Moher

Shamseer

Clarke

Ghersi

Liberati

Petticrew

Shekelle

Stewart

L. A.

PRISMA-P Group . (2015). Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement. Systematic Reviews, 4(1), 1. https://doi.org/10.1186/2046-4053-4-1

22.

Nejade

R. M.

Grace

Bowman

L. R.

(2022). What is the impact of nature on human health? A scoping review of the literature. Journal of global health, 12, Article 04099. https://doi.org/10.7189/jogh.12.04099

23.

Nguyen

P. Y.

Astell-Burt

Rahimi-Ardabili

Feng

(2023). Effect of nature prescriptions on cardiometabolic and mental health, and physical activity: A systematic review. The Lancet Planetary Health, 7(4), e313–e328. https://doi.org/10.1016/s2542-5196(23)00025-6

24.

Paterson

B. L.

Dubouloz

C.-J.

Chevrier

Ashe

King

Moldoveanu

(2009). Conducting qualitative metasynthesis research: Insights from a metasynthesis project. International Journal of Qualitative Methods, 8(3), 22–33. https://doi.org/10.1177/160940690900800304

25.

Sandelowski

(2012). Metasynthesis of qualitative research. APA handbook of research methods in psychology, Vol 2: Research designs: Quantitative, qualitative, neuropsychological, and biological (pp. 19–36). American Psychological Association. https://doi.org/10.1037/13620-002

26.

Sandelowski

Barroso

(2002). Finding the findings in qualitative studies. Journal of Nursing Scholarship: An Official Publication of Sigma Theta Tau International Honor Society of Nursing, 34(3), 213-219. https://doi.org/10.1111/j.1547-5069.2002.00213.x

27.

Sandelowski

Barroso

(2003a). Creating metasummaries of qualitative findings. Nursing Research, 52(4), 226-233. https://doi.org/10.1097/00006199-200307000-00004

28.

Sandelowski

Barroso

(2003b). Toward a metasynthesis of qualitative findings on motherhood in HIV-positive women. Research in Nursing & Health, 26(2), 153–170. https://doi.org/10.1002/nur.10072

29.

Sandelowski

Barroso

(2007). Handbook for synthesizing qualitative research. Springer Publishing Company.

30.

Sandelowski

Docherty

Emden

(1997). Focus on qualitative methods. Qualitative metasynthesis: Issues and techniques. Research in Nursing & Health, 20(4), 365-371. https://doi.org/10.1002/(sici)1098-240x(199708)20:4<365::aid-nur9>3.0.co;2-e

31.

Schreier

(2014). Ways of doing qualitative content analysis: Disentangling terms and terminologies. Forum Qualitative Sozialforschung / Forum for Qualitative Social Research, 15(1). https://doi.org/10.17169/fqs-15.1.2043

32.

Schreier

(2018). Sampling and generalization. In Flick

(Ed.), The sage handbook of qualitative data collection. Sage Publications Ltd. https://doi.org/10.4135/9781526416070

33.

Small

S. P.

(2023). Reflections on critical appraisal of research for qualitative evidence synthesis. JBI Evidence Synthesis, 21(6), 1064–1065. https://doi.org/10.11124/jbies-23-00198

34.

Strauss

Corbin

J. M.

(1990). Basics of qualitative research: Grounded theory procedures and techniques. Sage Publications, Inc.

35.

Strauss

Corbin

J. M.

(1997). Grounded theory in practice. Sage.

36.

Thorne

Jensen

Kearney

M. H.

Noblit

Sandelowski

(2004). Qualitative metasynthesis: Reflections on methodological orientation and ideological agenda. Qualitative Health Research, 14(10), 1342–1365. https://doi.org/10.1177/1049732304269888

37.

Tong

Flemming

McInnes

Oliver

Craig

(2012). Enhancing transparency in reporting the synthesis of qualitative research: ENTREQ. BMC Medical Research Methodology, 12, 181. https://doi.org/10.1186/1471-2288-12-181

38.

Ulrich

R. S.

Simons

R. F.

Losito

B. D.

Fiorito

Miles

M. A.

Zelson

(1991). Stress recovery during exposure to natural and urban environments. Journal of Environmental Psychology, 11(3), 201–230. https://doi.org/10.1016/S0272-4944(05)80184-7

39.

van den Berg

Wendel-Vos

van Poppel

Kemper

van Mechelen

Maas

(2015). Health benefits of green spaces in the living environment: A systematic review of epidemiological studies. Urban Forestry and Urban Greening, 14(4), 806–816. https://doi.org/10.1016/j.ufug.2015.07.008

40.

van den Bosch

Ode Sang

Å.

(2017). Urban natural environments as nature-based solutions for improved public health – A systematic review of reviews. Environmental Research, 158, 373–384. https://doi.org/10.1016/j.envres.2017.05.040

41.

World Health Organization (WHO), R. O. f. E. (2016). Urban green spaces and health. https://apps.who.int/iris/handle/10665/345751