Effects of Urban Forest Therapy on Depression, Anxiety, and Sleep Quality in People Experiencing Cancer
Article information
Abstract
Background and objective
The cancer survival rate in Korea exceeds 70%, but approximately two million people experiencing cancer face difficulties returning to daily life owing to a lack of appropriate psychological support, leading to depression, anxiety, and fear of recurrence. Despite the achievements of forest therapy, there is a dearth of research, particularly regarding its effects on people experiencing cancer. Therefore, this study examined the psychological effects of forest therapy using highly accessible urban forests after cancer treatment.
Methods
The study was conducted between April 11 and June 9, 2023, with 28 participants who had completed cancer treatment and could engage in outdoor activities without difficulty. They were divided into two groups: experimental and control. The experimental group received forest therapeutic program interventions in an urban forest once a week for 8 weeks. To measure the difference in the intervention effects between the two groups, pre-, mid-, and post-assessments were conducted using the Korean version of the Center for Epidemiological Studies-Depression Scale, the Beck Anxiety Inventory, and the Korean version of the Pittsburgh Sleep Quality Index.
Results
People experiencing cancer who participated in the urban forest therapeutic program had significantly reduced depression and anxiety than those in the no-treatment group. The experimental group's sleep quality also improved after participating in the program.
Conclusion
This study demonstrated that urban forest therapy can alleviate psychological difficulties in people experiencing cancer. These results suggest the need for further research into urban forest therapy as an intervention to improve the quality of life of people experiencing cancer.
Introduction
South Korea has high cancer survival rates owing to advancements in cancer diagnosis and treatment technology, as well as the promotion of early detection. According to statistics from the National Cancer Information Center (2023), there were around 2.28 million people experiencing cancer in 2020. The 5-year relative survival rate for people experiencing cancer diagnosed between 2016 and 2020 was 71.5%, meaning that more than 7 out of 10 individuals survived at least 5 years.
However, despite advances in oncology, cancer can recur even after receiving a complete remission diagnosis. As the survival period for people experiencing cancer increases, the duration of treatment also lengthens, resulting in higher psychological distress for both people experiencing cancer and their families (Seo and Park, 2013).
The National Comprehensive Cancer Network (NCCN) coined the term "distress" in 1999 to encompass the physical, psychological, and spiritual suffering of people experiencing cancer and created guidelines for distress management. The distress incurred by people experiencing cancer can range from normal reactions such as confusion, sadness, and fear to pathological states that result in psychological and social dysfunction, including depression, anxiety, panic, social isolation, and existential crises.
Jeon (2019) states that distress causes severe damage to the body's immune function, hindering treatment, therapeutic, and recovery. Seo (2013) identified depression, anxiety, insomnia, and delirium as the four major symptoms with a high prevalence among people experiencing cancer in South Korea. Furthermore, neglecting distress leads to a decrease in treatment compliance, indirectly increasing the mortality rate of cancer.
In meta-analysis studies (Güner et al., 2018; Mitchell et al., 2011), it was observed that 30 to 40% of people experiencing cancer had a mood disorder according to psychiatric diagnostic criteria. However, according to data from the National Health Insurance Service, only 10.4% of people diagnosed with cancer between 2005 and 2008 received a psychiatric diagnosis. Choi et al. (2014) found that while many people experiencing cancer report psychiatric difficulties, information on actual psychiatric care is scarce. In addition, the prevalence of psychiatric disorders was reported to be relatively very low, contrary to previous studies in other countries, suggesting that there are barriers to accessing psychiatric care rather than low prevalence. To address this gap, it is necessary to provide proactive psychological support (Shin, 2021).
Starting in 2009, the Ministry of Health and Welfare presented several research findings on the "Development of evidence-based, customized programs to improve quality of life and quality care for cancer patients" to manage their distress and enhance their quality of life. In addition, the 4th Comprehensive Cancer Management Plan (2021) announced a development plan to expand the 13 types of integrated support programs for cancer survivors ('20) to 33 types by 2025. However, physical, nutritional, and educational interventions are still emphasized, and psychological interventions are still lacking.
According to Oh and Choi (2012), psychological and social interventions for people experiencing cancer are dominated by pain education interventions (66.7%), indicating the need for the development of specialized and diverse psychological interventions for people experiencing cancer.
The American Psychiatric Association (1994) revised the DSM-IV to include people experiencing cancer as a population eligible for Post Traumatic Stress Disorder (PTSD) diagnosis (Shelby et al., 2005). Numerous studies have shown that cancer can induce PTSD symptoms in a significant number of individuals (Cordova et al., 2017; Dimitrov et al., 2019). In 2004, the Council of the Canadian Strategy for Cancer Control recommended including distress in cancer patients as a sixth vital sign and integrating distress management as a comprehensive part of cancer treatment (Bultz and Carlson, 2005; Rebalance Focus Action Group, 2005). There are recovery support programs for people experiencing cancer in Korea, but they are mainly physical fitness programs, such as walking and strength training, sleep hygiene, and educational programs to understand the disease. There are also social psychological programs such as meditation, writing, horticultural therapy, and counseling, but they are not enough to support psychological recovery.
Participants of the forest therapeutic programs engage in forest immersion. Shin (2007) reported a decrease in feelings of depression and anxiety, Yeon (2007) saw a decrease in anxiety and an increase in self-esteem among people with alcohol dependency, and Woo et al. (2012) documented a reduction in depressive symptoms and an increase in relaxation among individuals with major depressive disorder. A study conducted on people experiencing cancer also showed that forest therapeutic programs are the most effective therapeutic environment for reducing anxiety and depression (Kim, 2015), as well as enhancing physiological and psychological recovery and boosting the body's immune system (Kim, 2020).
While there is a growing body of research on the therapeutic and health-promoting effects of forest therapy, there is a lack of research on its effects on people experiencing cancer. This is thought to be due to the remoteness of therapeutic forests and the difficulty in recruiting, transporting, and securing the safety of participants. Therefore, we wanted to conduct forest therapy by utilizing urban forests that are highly accessible from residences and have relatively convenient facilities to relieve daily stress. This study was designed to verify the psychological and physiological health promotion effects of forest therapeutic programs in urban forests for people experiencing cancer, and to provide basic data for psychological intervention methods that can alleviate the stress of people experiencing cancer in the future.
Research Methods
Participants
The participants for this study were recruited through the website of the Chungbuk Regional Cancer Survivors Integrated Support Center at a university hospital in Cheongju, Chungcheongbuk-do. The eligibility criteria for participation were posted, and individuals who voluntarily wished to participate were selected. The sample size was 12 participants, based on the 6 to 10 participants who considered the forest therapeutic program to be an appropriate standard (Park et al., 2018), the number of participants who are efficient and satisfied with this researcher's experience, and the minimum number of participants in an experimental study. Considering the possibility of dropping out owing to the special characteristics of those with cancer, two people were added to each group. Among the applicants for forest therapy, 28 individuals were selected, 14 of whom could consistently participate in the 8-week program and were chosen as the experimental group. In contrast, the remaining individuals were selected as the control group.
The participants comprised 23 adult women and 5 men, all aged 40 or above. The selection criteria for participants were as follows: (1) individuals who had completed major cancer treatments, (2) with no cognitive impairments, (3) who understood and voluntarily agreed to participate in the study, and (4) were capable of outdoor activities. The exclusion criteria for participation were: (1) individuals currently undergoing surgery or cancer treatment and (2) individuals who could not engage in activities without a caregiver. Participants were guaranteed anonymity, and the study was approved by the Institutional Review Board of Chungbuk National University (CBNU-202302-HRBR-0009).
Research location
This study was conducted in an urban forest on the campus of Chungbuk National University located in Seowon-gu, Cheongju City. Urban forests are those created and managed by cities to promote public health, recreation, and emotional and experiential activities, and include living forests such as village forests, landscape forests, school forests, and trees. This campus was previously utilized as an arboretum and has a variety of plant resources, including large trees, ornamental trees, and flowering plants.
The research locations included Lawn Square, Deck Road, Metasequoia Path, Oriental Arborvitae Forest, Pine Tree Path, Platanus Path, and Solmot inside the Chungbuk National University campus. These locations are mostly situated on flat terrain, and Deck Road is a gentle 1.4 km long road that has been designed with universal design principles. The study site consists of a variety of different types of landscapes. Panoramic landscapes give participants a sense of openness, while canopied landscapes create a sense of forest-like mystery and intimacy, and are conducive to walking and meditation. Enclosed landscapes provide a sense of security and coziness, perfect for meditation and self-discovery, while focal landscapes guide your gaze to one place so you can focus (Fig. 1).
Pictures of the research site landscapes.
The locations were selected based on the theme, itinerary, and seasonal features of the program conducted on the day. The main species found at the research site were Pinus densiflora, Quercus dentata, Metasequoia glyptostroboides, Platycladus orientalis, Pinus koraiensis, Castanea crenata, Platanus occidentalis and Numphaea tetragona. The weather during the research period was predominantly clear, with an average temperature ranging from 14 to 2 2°C.
Research procedure
Research process
This study was designed with an experimental and a control group to measure the psychological effects of participating in an 8-week forest therapeutic program on health promotion. The research was conducted from April 11th, 2023, to June 9th, 2023, from 10:00 a.m. to 12:00 p.m. The experimental group participated in an 8-session program, each lasting 2 hours, once a week. The main objective of this program was to reduce depression and anxiety in people experiencing cancer.
The experimental and control groups underwent a preliminary psychological test after receiving a sufficient explanation of the program and evaluation tools in advance. In addition, a psychological test was conducted after 4 sessions and after 8 sessions, and a total of 3 psychological evaluations were conducted. The researcher supervised the forest therapeutic program's development, operation, and implementation for the entire session as a first-class forest therapy instructor. To ensure the participants' safety and efficient progress, a total of 3 assistants, including 2 assistant instructors (a nurse specializing in forest therapy and a forest education expert) and 1 safety manager, helped with the proceedings.
Program
The forest therapeutic program in this study was designed by the researcher based on Mindfulness Based Stress Reduction (MBSR), Mindfulness Self Compassion (MSC), and Acceptance and Commitment Therapy (ACT), in accordance with Oh et al's (2016) stages of forest therapy. The program was modified and supplemented with input from experts related to forest therapeutic (one psychological counselor, two professors from a health university) and one professor of education to increase the psychological and physical safety of participants and the effectiveness of the program. In addition, meditation, barefoot walking, tea drinking, and aromatherapy programs that received high scores in a forest therapeutic program preference survey of 23 people experiencing cancer were included.
MBSR is a meditation program that involves looking at oneself and the external world "as it is" and incorporates the attitudes of non-judging, non-striving, acceptance, and letting go into the program. MSC meditation teaches that suffering is universal and that you must recognize it for what it is, accept the experience, and be kind to yourself. ACT is a 3rd generation model of cognitive behavioral therapy that promotes psychological flexibility and behavioral change by acknowledging and accepting the suffering caused by one's flaws but thinking about them in a new light.
MBSR, MSC, and ACT teach people experiencing cancer to let go of blame for their illness in a non-judgmental way, accepting their pain as it is rather than avoiding it and comforting themselves in times of distress, which reduces stress and improves depression and anxiety.
In addition, a forest provides a restorative environment— owing to, for example, its secluded, low-stimulus environment and pleasant air—which helps psychological recovery from the stressful environment of everyday life. Forest therapeutic programs provide opportunities to reduce anxiety and depression through relaxation, positive stimulation, and self-reflection using appropriate static and dynamic activities, as well as the discovery of one's self-worth (Shin et al., 2007).
The forest therapeutic program is organized into themes for each park based on the six stages of Oh et al.'s (2016) forest therapeutic phenomenon (Table 1). Stage 1 is stimulation, where the senses and emotions come alive with positive stimulation from the therapeutic factors of the forest. Stage 2 is the experience of acceptance through the comfort and peacefulness of the forest. Stage 3 is purification, where the mind is opened and negative emotions are emptied and released. Stage 4 is insight, where you become aware of reality and discover yourself. Stage 5 is hope and filling with positive energy. Stage 6 is change, which is therapeutic restoration and self-actualization through selfdirected living.
Activity contents for forest therapeutic program
Weeks 1 through 4 involved sensory stimulation in the woods, such as foot sole sensing, barefoot walking, breathing awareness, and aromatherapy, to help participants feel emotionally transformed through communing with nature.
For psychological acceptance and cleansing, we did forest commentary, activities to release worry and anxiety, gratitude journaling, breathing, and singing ball meditation. Weeks 5–7 were devoted to cognitive shifts through connecting with oneself, including forest play, noticing one's feelings and values, affirmations, self-compassion and internal acceptance meditations, and strengths-based praise relay. Week 8 was for behavioral change through interaction with the outside world, where participants identified emotional changes over the eight weeks, expressed and shared their feelings in photos, and created and gifted a love tree with MSC meditations and praise for others.
Test tools and analysis method
Psychological tests (Questionnaires)
To examine participants' psychological changes, psychological measurements were conducted three times: before the program, at the midpoint (4 sessions), and after the program (8 sessions). The scales used were the CES-D (Center for Epidemiological Studies Depression Scale), BAI (Beck Anxiety Inventory), and PSQI-K (Pittsburgh Sleep Quality Index-K).
The CES-D is a questionnaire for measuring depressive symptoms. It was initially developed by Radloff (1977) and revised by Jeon, Choi, and Yang (2001) to provide a comprehensive Korean version.
The CES-D is a self-report instrument consisting of 20 items in which participants rate their feelings and behaviors during the past week using a 4-point Likert scale. The rating scale ranges from 0 to 60 points, with "extremely rare" being 0 points, "occasionally" being 1 point, "frequently" being 2 points, and "almost always" being 3 points. A higher total score indicates a more severe level of depression. The normal range is defined as 0 to 15 points, mild depression is classified as 16 to 24 points, and severe depression is categorized as 25 points or higher. In this study, the Cronbach's α value of CES-D was 0.705 for pre and 0.671 for post.
The BAI is a questionnaire developed by Beck et al. (1988) and adapted by Yook and Kim (1997). The BAI consists of a total of 21 items, with each item scored on a scale of 0 to 3. The total score ranges from 0 to 63, with higher scores indicating higher anxiety levels. The scoring system by Lee et al. (2016) used in the study interprets scores from 0 to 7 as normal levels, scores from 8 to 15 as mild anxiety, scores from 16 to 25 as moderate anxiety, and scores of 26 or higher as severe anxiety. In this study, the Cronbach's α value of BAI was 0.959 for pre and 0.960 for post.
The PSQI-K is a tool developed by Buysse (1989) and translated into a Korean version by Sohn et al. (2012). It is a subjective assessment tool for evaluating sleep over one month. The total score for the subscales of PSQI-K ranges from 0 to 21, with higher scores indicating lower sleep quality. In this study, the Cronbach's α value of PSQI-K was 0.790 for pre and 0.859 for post.
Data analysis (method)
The data collected for this study were analyzed using the SPSS version 23 program, and p<.05 was used as the level of significance for statistical analysis. Frequency analysis and a homogeneity test were performed to determine the demographic characteristics. To examine the differences in depression, anxiety, and sleep quality between the experimental and control groups, each group was administered a self-report questionnaire three times: before, after 4 sessions, and after 8 sessions, and repeated measures ANOVA was used to analyze the results. If significant differences were found, a Bonferroni post-hoc analysis was performed to determine within-group differences. The PSQI-K was not found to be significant between groups, so a paired samples t-test was conducted to examine within-group changes over time.
Results and Discussion
Research results
Demographic characteristics
A survey of demographic characteristics was conducted on 28 participants before they participated in the program. The proportions of cancer types and the post-cancer survivorship, as determined by basic statistics, and general characteristics of the study participants are shown in Table 2.
General characteristics and homogeneity between groups
The most common type of cancer was breast cancer, accounting for 15 individuals (53.6%). The major cancers, thyroid cancer, lung cancer, stomach cancer, and colorectal cancer, each accounted for 2 individuals (7.1%), while pancreatic cancer accounted for 1 individual (3.6%). Other types of cancer (uterine cancer, ovarian cancer, multiple myeloma, prostate cancer) each accounted for 1 individual, totaling 4 individuals (14.3%). Most participants (42%) had a post-cancer survival period of less than 2–5 years, while 10 participants (40%) had a survival period of 5–10 years.
The homogeneity test of general characteristics utilized the chi-square test when the assumptions of equal variance and normality were satisfied, and the Fisher exact test was employed when the assumptions were not met. The participants consisted of 5 men (17.6%) and 23 women (82.1%), with 22 individuals (78.6%) in the age range of 50–60, 2 individuals (7.1%) in their 40s, and 4 individuals (14.3%) in their 70s. Most, specifically 17 individuals (60.7%), had a high school or lower educational background. Furthermore, 27 individuals (96.4%) were married. While there was a statistically significant difference in marital status, there were no statistically significant differences in sex, age, and education level, indicating that the groups are homogeneous.
Homogeneity test
The homogeneity test results for the preliminary survey data between groups are shown in Table 3. The preliminary homogeneity analysis using the psychological questionnaires CES-D, BAI, and PSQI-K showed no statistically significant differences between the experimental and control groups. Therefore, the two groups proved to belong to the same population and were deemed appropriate to proceed with the study.
Homogeneity of each survey between groups
Psychological questionnaire test
All dependent variables in this study were extracted from different groups for the control and experimental groups, thus satisfying independence.
In all cases, both CES-D and BAI satisfied the p-value > .05 condition in the Shapiro test for normality, considering both groups and time points. Additionally, the W-values of Mauchly's test for depression and anxiety, 0.786 and 0.87, respectively, were close to 1, indicating sphericity. Therefore, a repeated measures two-way ANOVA was conducted. The sphericity test of the PSQI-K showed that the variance was homogeneous with a significance probability of 0.895, so a repeated measures two-way ANOVA was conducted.
The center for epidemiologic studies depression scale (CES-D)
A repeated measures ANOVA was used to examine differences in depression between the experimental and control groups after the 8 sessions of the forest therapy. First, we examined the differences between the two groups over time and within each group using the within each group. Then, we used a post-hoc analysis (Bonferroni) to examine the differences within the two groups at each time. Table 4 shows the pre, 4-session, and 8-session post-test results of the experimental and control groups to investigate the effect of the forest therapy on the depression of people experiencing cancer. A repeated measures ANOVA was conducted to test the change in depression of 28 people experiencing cancer, 14 in the experimental group and 14 in the control group, according to whether they participated in the forest therapeutic program or not. The effect of the interaction between time and program participation status on depression between groups was statistically significant at the F = 3.997, p = .020 level. In other words, there was a statistically significant difference in the change in depression after 8 sessions between the forest therapeutic program experimental group and the control group. Furthermore, a repeated measures ANOVA was conducted for each group to examine the difference in depression between the groups; the difference was significant at the F = 3.676, p = .03 9 level. The Bonferroni post-hoc analysis (see bottom of Table 4) showed a statistically significant difference in depression between pre (M = 18.8, SD = 6.54) and post 4 sessions (M = 23.7, SD = 7.64) at the p = .047 level in the control group.
Repeated measures ANOVA of depression (CES-D) between groups
The experimental group had higher depression than the control group before (M = 21.7, SD = 7.9), but depression decreased after 8 sessions (M = 18.2, SD = 4.54). Although not statistically significant, depression decreased in the experimental group as they participated in forest therapy, while depression increased in the control group, resulting in a larger mean difference between the groups.
A forest provides a restorative environment—owing to, for example, a secluded, low-stimulus environment and pleasant air—and help people recover mentally and psychologically by reducing negative emotions such as depression and anxiety by escaping from the stressful environment of everyday life. In addition, interaction with the natural environment has positive physical effects, such as reducing stress hormones, relaxing muscles, and lowering blood pressure by regulating the balance of autonomic nerves. Shin et al. (2007) also found that, in addition to the forest environment, forest therapeutic programs provide opportunities to reduce anxiety and depression through relaxation and positive stimulation through appropriate static and dynamic activities and the discovery of one's own values through reflection and acceptance activities.
The findings of this study are consistent with research suggesting that a group of diseases that are highly correlated with stress are suitable for forest therapy (Park et al., 2012) and a meta-analysis by Lee et al. (2017) and Yeon et al. (2021) that found forest therapy to be an effective intervention for reducing depressive symptoms in adults.
Beck's anxiety inventory (BAI)
Table 5 shows the results of repeated measures ANOVA to test the difference in anxiety between the experimental and control groups after participating in forest therapy. The interaction effect of group by time and program participation was statistically significant at the F = 3.576, p = .035 level. Accordingly, a repeated measures ANOVA was conducted again to examine the change in anxiety in each group, and a statistically significant difference was found at the F = 5.24, p = .012 level in the experimental group only (p < .05). Bonferroni post-hoc analysis showed that the experimental group decreased anxiety from post 4 sessions (M = 15.4, SD = 12.92) to post 8 sessions (M = 10.3, SD = 9.67), a statistically significant difference at p = .012. In the control group, anxiety increased over time from pre (M = 12.1, SD = 12.7) to post 8 sessions (M = 14.7, SD = 12.9). Anxiety was lower in the control group than in the experimental group at baseline but increased over time, indicating that the forest therapeutic program was effective in reducing anxiety.
Repeated measures ANOVA of anxiety (BAI) between groups
Shin et al. (2007) suggested that forests may have positively affected anxiety reduction owing to the sense of escape from daily routine and the freedom and emotional bondage it provides. Kim (2019) also found that for people experiencing cancer who were sensitive to stress, forest therapy relieved stress, relaxed them psychologically and physically, and increased their positive emotions. Park et al. (2012) conducted an expert Delphi survey and found that anxiety and depression, which are highly correlated with stress, were the most suitable conditions for applying forest therapy. Kim et al.'s (2015) study of people experiencing cancer also found that depression and anxiety decreased after forest therapy, providing evidence for the present study's findings that anxiety decreased after forest therapy.
Pittsburgh sleep quality index-K(PSQI-K)
Table 6 shows the results of the analysis to test the difference in sleep between the experimental and control groups according to participation in the forest therapeutic program. The interaction effect of group by time was not statistically significant at F = 2.018, p = .143. Therefore, repeated measures ANOVA was conducted again for each group to test the difference in sleep quality, and the control group showed no statistically significant difference at F = 1.16, p = .330, and the experimental group showed no statistically significant difference at F = 3.14, p = .060.
Repeated measures ANOVA of quality of sleep (PSQI-K) between groups
A PSQI-K score of 0 to 4 is normal, and higher scores indicate poor sleep quality. In this study, the control group's PSQI-K scores increased over time, while the experimental group's scores decreased significantly, but there was no significant difference between the groups. Therefore, a paired samples t-test was conducted to examine differences over time within each group. We tested whether there was a difference in sleep quality between the experimental and control groups according to the three time periods: pre-4 sessions, 4 sessions to 8 sessions, and pre-8 sessions. As a result, the experimental group showed a statistically significant difference of p = .038 in the pre-8 sessions period, indicating that the forest therapy improved the sleep quality of people experiencing cancer (Table 7). This result is consistent with studies finding that forest therapy improves insomnia symptoms in high-stress healthcare workers (Paek et al., 2022) and improves sleep quality in people experiencing cancer (Kim, 2019). Additionally, the restorative environment of the forest, moderate physical activity, and stress relief from the forest therapy program may have had a positive impact on sleep quality.
Paired samples t-test of quality of sleep (PSQI-K) within groups over time
Sleep disorders are one of the most common symptoms for people experiencing cancer (Divani et al., 2022) and the most frequent disorder among all people experiencing cancer (Choi et al., 2014). Despite the high prevalence of sleep disorders, they have been undervalued owing to their association with cancer itself and other problems such as pain. Improving sleep is an urgent issue for people experiencing cancer, as sleep has a role in maintaining immunity, metabolism, and quality of life (Ban et al, 2013); shortened sleep duration has been consistently associated with negative physical and mental health outcomes (Galinsky et al, 2018). Pharmacologic therapies have been used to reduce sleep disturbances in people experiencing cancer, but these therapies face challenges of tolerance and abuse. As the survival rate of people experiencing cancer increases, so does the importance of their sleep quality, but there is a lack of research on non-drug intervention programs for sleep disorders in people experiencing cancer in Korea and abroad (Oh and Kim, 2022) more research is needed.
Conclusion
This study investigated the psychological and physiological effects of forest therapy on people experiencing cancer by utilizing highly accessible urban forests to develop psychological interventions for them. The results showed that after the forest therapy, the participants had significantly reduced depression and anxiety and improved sleep quality.
People experiencing cancer often suffer from persistent anxiety and fear from diagnosis through treatment and regular check-ups, which can lead to depression and sadness, negatively impacting cancer treatment. Participants in this study reported feeling lighter, refreshed, and more relaxed after forest therapy, as their minds were emptied of complex thoughts. They also reported that their worries were diluted, they felt revitalized and energized to get through the week, and they felt more comfortable relating to family and friends. Participants who had difficulty walking long distances said they felt like they were in a forest hotel, as the well-maintained facilities in the urban forest allowed them to experience a forest that was otherwise difficult to get to.
These findings suggest the need for forest therapy research utilizing urban forests to improve the recovery and quality of life of people experiencing cancer. As the number of such people continues to increase owing to early diagnosis and improved survival rates, psychological interventions are increasingly needed to improve their health and quality of life. Therefore, we would like to explore the promotion of forest therapeutic as an intervention for people experiencing cancer.
First, healthcare policies need to be improved. According to the Central Cancer Registry's 2021 statistics, if Koreans survive to the life expectancy of 83.5 years, the probability of developing cancer is 36.9%. Therefore, the management of people experiencing cancer is now beyond the individual and requires social management by the government to improve the quality of life of such people by organizing a national psychosocial support system and offering financial support.
Second, research and development of a forest therapy manual tailored to the specificity of cancer and the stage of stress of people experiencing cancer is needed. The National Cancer Center's "Cancer Patients and Distress" (2023) noted that there is a lack of practical manuals on distress for people experiencing cancer that can be used consistently in clinical practice. Several studies have shown that forest therapeutic reduces stress in people experiencing cancer, and the development of manuals should be preceded by linking support and rehabilitation services between hospitals and community health centers. Continued state support is needed for research and development to validate the medical and scientific effects of forest therapy.
Third, given that 90% of the world's population lives in cities, there is a need to create therapeutic spaces in highly accessible urban forests. As a healthcare and leisure trend after the pandemic, people's interest and preference for nature-friendly outdoor activities are increasing. In response to this, urban forest construction projects are actively underway across Korea. Therefore, when creating a new urban forest, it is necessary to differentiate the design of the therapeutic environment from the existing park design to create an evidence-based therapeutic environment (Park and Lee, 2016).
However, this study has several limitations. First, the sample size was small, with 14 participants in the experimental and control groups, respectively, and gender was not considered. Second, the participants were mostly adults aged 40 and older who live in Chungcheongbuk-do, which limits generalization. Third, the short study period was insufficient to fully verify the effectiveness of forest therapy. Future studies should expand the number of participants and consider gender ratio, cancer-specificity, postcancer survivorship stages that require psychological interventions, and application in other regions. Furthermore, qualitative research on the experience of forest therapy is needed, along with ongoing analysis of the effectiveness of forest therapy among people experiencing cancer. Improving our understanding of the therapeutic process in the forest will help us to develop effective interventions to ameliorate psychological difficulties in people experienced cancer.