Self-help Forest Bathing (Shinrin-yoku) on Depression, Anxiety, and Stress

Efficacy of Self-help Forest Bathing (Shinrin-yoku) on Depression, Anxiety, and Stress: A Pilot Randomized Controlled Trial

The objective of this pilot randomized controlled trial is to evaluate the efficacy and acceptability of self-help forest bathing on depression, anxiety, and stress in the Hong Kong adult population.

Prior to all study procedures, eligible participants will be required to complete an online informed consent form (with telephone support). Around 80 eligible participants aged between 18 to 65 years old with at least a mild level of depression, anxiety, or stress symptoms will be randomly assigned to either the self-help forest bathing intervention group (FB group) or the waitlist control group (WL group) in a ratio of 1:1.

Participants in the FB group will receive forest bathing guidance via an in-house smartphone app. The WL group will be asked to maintain their typical activity in week 1-7. This group will receive the guide upon trial completion in week 8.

The outcomes of the interest will include generalized anxiety symptoms, depressive symptoms, insomnia symptoms, wellbeing, health-related quality of life, functional impairment at baseline (week 0), immediate (week 7), and 1-month post-intervention assessments (week 10). Treatment credibility and acceptability will be collected at baseline and immediately after the intervention.

Study Overview

• Status: Not yet recruiting
• Conditions: Stress; Depression, Anxiety
• Intervention / Treatment: Behavioral: Self-help Forest Bathing

• Study Type: Interventional
• Enrollment (Anticipated): 80
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Ka Man Ho, MA in Psychology; Phone Number: 852-39436575; Email: 1155016857@link.cuhk.edu.hk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Hong Kong residents;
2. Aged between 18 to 65 years;
3. Meet the threshold for mild depression (score of >5 on the Patient Health Questionnaire 9 [PHQ-9], anxiety (>5 Generalized Anxiety Disorder 7 [GAD-7]), or stress (>15 on the Depression, Anxiety, and Stress Scale [DASS-21] stress subscale, after multiplying score by 2);
4. Able to read and understand Chinese and type in Chinese or English
5. Have an Internet-enabled mobile device (iOS or Android operating system)
6. Willing to provide informed consent and comply with the trial protocol

Exclusion Criteria:

1. Received psychotherapy for depression, anxiety and stress in the past 6 months;
2. A change in psychotropic drugs or over-the-counter medications that target depression, anxiety, and stress within 2 weeks before the baseline assessment.
3. Patient Health Questionnaire-9 (PHQ-9) item 9 score > 2, indicating a moderate level of suicidal risk that requires active crisis management (referral information to professional mental health services will be provided);
4. Currently participating in another intervention study that may potentially affect mental health;
5. Self-disclosure of having unsafe health conditions for which physical activity was contraindicated by physicians;
6. Self-disclosure of any psychiatric, medical, or neurocognitive disorder(s) that makes participation unfeasible;
7. Pregnancy;
8. Hospitalization.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Single Group Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Self-help Forest Bathing Group; Participants in the FB group will perform forest bathing activity at the Chinese University of Hong Kong for two session.	Behavioral: Self-help Forest Bathing; The self-help forest bathing includes two sessions (i.e., participants will perform the first intervention within week 1 to 3, and the second intervention within week 4 to 6) that are related to the following forest bathing activities : (a) forest meditation, (b) forest walking, (c) calling attention to sensory experiences of the forest, including seeing, hearing, touching, and smelling, and (d) building connection to the nature by partnership invitation. Each session will last for 45 minutes.
Other: Wait List Group	Behavioral: Self-help Forest Bathing; The self-help forest bathing includes two sessions (i.e., participants will perform the first intervention within week 1 to 3, and the second intervention within week 4 to 6) that are related to the following forest bathing activities : (a) forest meditation, (b) forest walking, (c) calling attention to sensory experiences of the forest, including seeing, hearing, touching, and smelling, and (d) building connection to the nature by partnership invitation. Each session will last for 45 minutes.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the Patient Health Questionnaire (PHQ-9)	The PHQ-9, a 9-item questionnaire used for screening, diagnosing, monitoring, and measuring the severity of depression, which scores each of the nine DSM-IV criteria as "0" (not at all) to "3" (nearly every day).	Baseline, immediate post-treatment, and 1-month follow-up

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the Credibility-Expectancy Questionnaire (CEQ)	The 6-item CEQ yielded ratings of treatment credibility, acceptability/satisfaction, and expectations for success. Specific wording referencing "anxiety" was changed to refer to "depression".	Baseline and immediate post-treatment
Change in the Treatment Acceptability and Adherence Scale (TAAS)	TAAS is a self-reported, ten-item questionnaire that is rated by a seven-point Likert scale from 1 to 7, and it aims at evaluating the clients' attitude toward the treatment sessions by four domains, including acceptability, adherence, drop-out, and distress. Specific wording referencing "anxiety" was changed to refer to "depression".	Baseline and immediate post-treatment
Change in the Generalized Anxiety Disorder 7-Item Scale (GAD-7)	The GAD-7, a 7-item questionnaire used for screening, diagnosing, monitoring, and measuring the severity of anxiety over the past two weeks on a 4-point scale, "0" (not at all) to "4" (nearly every day).	Baseline, immediate post-treatment, and 1-month follow-up
Change in the Perceived Stress Scale (PSS)	The PSS, a 10-item questionnaire measuring the perceived degree of stress across situations over the past month. Items include how unpredictable, uncontrollable, and overloaded do the respondents perceive. The score ranges from "0" (never) to "4" (very often).	Baseline, immediate post-treatment, and 1-month follow-up
Change in the Insomnia Severity Index (ISI)	ISI is a 7-item scale designed to evaluate perceived insomnia severity. Ratings on the 5-point Likert scale are obtained on the perceived severity of sleep-onset, sleep-maintenance, early morning awakening problems, satisfaction with current sleep pattern, interference with daily functioning, noticeably of impairment attributed to the sleep problem, and level of distress caused by the sleep problem.	Baseline, immediate post-treatment, and 1-month follow-up
Change in the The World Health Organisation- Five Well-Being Index (WHO-5)	WHO-5 is a short and generic global rating scale measuring subjective well-being.	Baseline, immediate post-treatment, and 1-month follow-up
Change in the Sheehan Disability Scale (SDS)	SDS is a brief, 5-item self-report tool that assesses functional impairment in work/school, social life, and family life.	Baseline, immediate post-treatment, and 1-month follow-up
Change in the Short Form (Six-Dimension) Health Survey (SF-6D)	A preference-based single index measure of health. A six-digit number represents each SF-6D health state, each digit denotes the level of one of six SF-6D dimensions: physical functioning, role limitation, social functioning, bodily pain, mental health, and vitality. The SF-6D index, scored from 0.0 (worst health state) to 1.0 (best health state)	Baseline, immediate post-treatment, and 1-month follow-up

Collaborators and Investigators

• Sponsor: Chinese University of Hong Kong
• Investigators: Study Chair: Fiona Yan-Yee Ho, Chinese University of Hong Kong

Study record dates

Study Major Dates

• Study Start (Anticipated): February 1, 2023
• Primary Completion (Anticipated): December 1, 2023
• Study Completion (Anticipated): December 1, 2023

Study Registration Dates

• First Submitted: February 16, 2023
• First Submitted That Met QC Criteria: February 16, 2023
• First Posted (Actual): February 24, 2023

Study Record Updates

• Last Update Posted (Actual): February 24, 2023
• Last Update Submitted That Met QC Criteria: February 16, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: Depression; Anxiety; Stress; Randomised controlled trial; Lifestyle medicine
• Additional Relevant MeSH Terms: Behavioral Symptoms; Mental Disorders; Mood Disorders; Depression; Depressive Disorder; Anxiety Disorders
• Other Study ID Numbers: PSY030

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No