Feasibility, Acceptability, and Preliminary Efficacy of Yoga-based Group Intervention for Outpatients With Schizophrenia Spectrum Disorders (YOGIA)

Feasibility, Acceptability, and Preliminary Efficacy of Yoga-based Group Intervention for Outpatients With Schizophrenia Spectrum Disorders (YOGIA Study) - a Three-arm, Single-blind Randomized Controlled Pilot Study

A three-arm pilot rater-blinded randomized controlled trial is conducted, comprising Yoga-based Group Intervention (YoGI + TAU) as the experimental condition, a strength and flexibility training (SFT + TAU) group, and treatment as usual (TAU). Participants in all conditions receive the respective intervention in addition to treatment as usual (TAU) in outpatient settings in Germany. The interventions are designed for patients with schizophrenia spectrum disorders. To examine feasibility, acceptability, and preliminary efficacy, self-report measures and blinded rater-based assessments are administered at baseline (T0), after 12 weeks of participation (T1), and at a 3-month follow-up (T2). Before each intervention session, acute stress (general stress and symptom-related distress) is measured using a visual analogue scale. After each intervention session, acute stress (general stress and symptom-related distress; visual analogue scale), perceived effort (BORG-RPE-Scale), and the occurrence of unpleasant experiences are recorded via self-report, while instructors rate exercise performance and overall participation quality. In addition, semi-structured interviews are conducted at T0 and T1 to assess subjective mechanisms of change and relevant processes.

The primary outcomes of this trial are the feasibility and acceptability of YoGI and the SFT, assessed through recruitment and retention rates, adherence, and participant feedback. Based on recommendations for pilot studies of 20-50 participants, a conservative target sample size of 60 patients was determined. Further, the trial will evaluate secondary outcomes, including (body) mindfulness (SMQ, BMQ), symptoms of depression, anxiety, and stress (DASS, CDSS), positive and negative symptomatology (PANSS), psychological flexibility (CFQ), psychological well-being (WHO-QoL-BREF), social functioning (PSP), subjectively perceived cognitive functioning (SSTICS), and physical activity (SIMPAQ). This study aims to provide preliminary evidence for the efficacy of YoGI in comparison to both SFT and a TAU, and to establish a foundation for a future fully powered randomized controlled trial.

Study Overview

• Status: Recruiting
• Conditions: Psychotic Disorders; Schizophrenia Spectrum Disorders
• Intervention / Treatment: Behavioral: Yoga-based Group Intervention (YoGI) and treatment as usual (TAU); Behavioral: Strength and Flexibility Training (SFT) and TAU

Detailed Description

Patients are recruited across Berlin through psychiatric outpatient departments, the outpatient clinics of Charité, and social media. Recruitment occurs either through direct approach by psychologists or psychotherapists in training, or via informational posters and flyers. At baseline, eligibility screening is conducted by a blinded psychologist who is independent of the intervention delivery. This psychologist introduces the study, obtains electronic informed consent, and administers the self-report and clinician-rated assessments.

Given the behavioral nature of the interventions, participants and therapists are informed about group allocation after randomization. Randomization is performed using an Excel-generated list with block randomization (block size = 4).

Data management adheres to standard data protection procedures, including the use of anonymized identification codes and secure storage in an online database accessible only to authorized research team members. Participants retain the right to access their data and to request its deletion at any time. Upon completion of the study, each participant will receive compensation of 50 €.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Kerem Böge, Prof. Dr. Dr.; Phone Number: +4930450517319; Email: kerem.boege@charite.de

Study Locations

• Germany
  • Berlin, Germany, 10117
    • Recruiting
    • Charité - Universitätsmedizin Berlin Klinik für Psychiatrie und Psychotherapie, Campus Charité Mitte
    • Contact: Kerem Böge, Prof. Dr. Dr.; Phone Number: +4930450517319; Email: kerem.boege@charite.de

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Diagnosis of Schizophrenia Spectrum Disorder by previous (medical) reports according to ICD-10/ DSM-V
• Treated as psychiatric outpatients
• Age between 18 and 65 years
• Ability to give informed consent
• Willingness and ability to engage in psychotherapeutic group therapy
• Low to moderate psychotic state indicated with a score of ≤ 6 for each item at the Positive scale of the Positive and Negative Syndrome Scale (PANSS, Peralta & Cuesta, 1994)

Exclusion Criteria:

• Neurological disorders and history of severe traumatic brain injury in the past that may affect cognitive functioning
• Acute substance dependence, excluding nicotine and prescribed medication
• PANSS-P score on one item > 6 (= very severe)
• Ineligibility for group participation
• Acute suicidality, indicated by a score > 1 on item 8 of the Calgary Depression Scale for Schizophrenia (Addington, Addington, Maticka-Tyndale, & Joyce, 1992)
• Conflicting co-therapy such as electroconvulsive therapy or ketamine treatment as well as intensive psychotherapy

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental: Yoga-based Group Intervention (YoGI); It combines breathing exercises (pranayama), sitting, standing and lying positions (asanas), as well as relaxation techniques (shavasana). Participation is also possible from a chair, thereby ensuring accessibility for all patients, irrespective of their physical condition. The 50-minute Yoga-based Group Intervention sessions are conducted once a week over a period of 12 weeks by psychologists or psychotherapists in training who have obtained supplementary certification in yoga therapy. Additionally, study participants receive the standard outpatient care (TAU) provided in Germany.	Behavioral: Yoga-based Group Intervention (YoGI) and treatment as usual (TAU); YoGI combines breathing exercises (pranayama), sitting, standing and lying positions (asanas), as well as relaxation techniques (shavasana). Participation is also possible from a chair, thereby ensuring accessibility for all patients, irrespective of their physical condition. The 50-minute Yoga-based Group Intervention sessions are conducted once a week over a period of 12 weeks by psychologists or psychotherapists in training who have obtained supplementary certification in yoga therapy. Additionally, study participants receive the standard outpatient care (TAU) provided in Germany.
Active Comparator: Active Comparator: Strength and Flexibility Training (SFT) and TAU; The SFT intervention is delivered once weekly over a 12-week period. Each 50-minute group session comprises a brief warm-up with mobilization and preparatory exercises, a main phase focused on full-body strengthening and flexibility exercises, and a concluding stretching segment. Participation is also possible from a chair, thereby ensuring accessibility for all patients, irrespective of their physical condition. Sessions are conducted by qualified psychologists or psychotherapists in training in a designated sports facility. The SFT sessions are designed by a psychotherapist in training who has obtained supplementary certification in yoga therapy together with sport therapists.	Behavioral: Strength and Flexibility Training (SFT) and TAU; The SFT intervention is delivered once weekly over a 12-week period. Each 50-minute group session comprises a brief warm-up with mobilization and preparatory exercises, a main phase focused on full-body strengthening and flexibility exercises, and a concluding stretching segment. Participation is also possible from a chair, thereby ensuring accessibility for all patients, irrespective of their physical condition. Sessions are conducted by qualified psychologists or psychotherapists in training in a designated sports facility. The SFT sessions are designed by a psychotherapist in training who has obtained supplementary certification in yoga therapy together with sport therapists.
No Intervention: No Intervention: Treatment as usual; Participants assigned to this group receive treatment as usual (TAU) for 12 weeks. During this period, there is no contact, except for a follow-up at 8 weeks to inform them about the next steps for T1.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of participants receiving threshold dose (Acceptability)	The proportions of participants receiving a threshold dose of the intervention (50% or more) and the proportion of participants with outcome measures at post-intervention and data completion. (Adherence and retention rate)	18 months
Nr. of participants willing to participate in YoGI (Operational Feasibility)	The number of eligible participants that are willing to participate in YoGI (recruitment)	18 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
SMQ Mindfulness	Southampton mindfulness questionnaire (SMQ), 16 items on a scale from 1 (applies fully) to 7 (does not apply at all)	18 months
CFQ Cognitive Fusion	Cognitive Fusion Questionnaire (CFQ), 7 questions that can be answered on a scale from 1(not applicable) to 7 (applies always)	18 months
PANSS Symptomatology - Positive and Negative Symptoms	Positive Symptoms as measure by the Positive and Negative Syndrome Scale (PANSS) to assess symptoms on a scale from 1 (non-existent) to 7 (extremely severe, 14 questions)	18 months
BMQ Body Mindfulness	Body Mindfulness Questionnaire (BMQ), 14 items on a scale from 1 (not at all) to (5) every day.	18 months
DASS Symptoms - Depression and Anxiety	Depression Anxiety Stress Scales (DASS), 21 questions that can be answered on a scale from 0 (does not apply to me) to 3 (applies to me strongly/most of the time	18 months
CDSS Calgary Depression Scale for Schizophrenia	Calgary Depression Scale for Schizophrenia (CDSS), 9 items assessing depressive symptoms in schizophrenia, designed to minimize overlap with negative symptoms commonly observed in schizophrenia; each item rated on a scale from 0 (absent) to 3 (severe).	18 months
PSP Personal and Social Performance	Personal and Social Performance Scale (PSP), Interview measures personal and social functioning in the domains of: Socially useful activities (eg. work and study), Personal and social relationships, Self-care, Disturbing and aggressive behaviors. The scale compromises four domains/items rated on a scale from absent to highly severe.	18 months
WHO-QOL-Bref Quality of Life - domains assessed include physical and psychological health, social relationships and environment	World Health Organisation Quality of Life (WHO-QOL-Bref) to assess quality of life measured on a scale from 1 (never) to 5 (always). Facets incorporated in the 4 domains: 1. Physical health - Activities of daily living, Dependence on medicinal substances and medical aids, Energy and fatigue, Mobility Pain and discomfort, Sleep and rest, Work Capacity; 2. Psychological - Bodily image and appearance, Negative feelings, Positive feelings, Self-esteem, Spirituality / Religion / Personal beliefs, Thinking, learning, memory and concentration; 3. Social relationships - Personal relationships Social support, Sexual activity; 4. Environment - Financial resources, Freedom, physical safety and security, Health and social care: accessibility and quality, Home environment, Opportunities for acquiring new information and skills, Participation in and opportunities for recreation / leisure activities, Physical environment (pollution / noise / traffic / climate), Transport	18 months
SSTICS Subjective Scale to Investigate Cognition in Schizophrenia	Simple Physical Activity Questionnaire (SIMPAQ), 5 items assessing physical activity and sedentary behavior in populations with severe mental illness. Covers time spent in bed, sedentary time, walking, structured exercise, and incidental activity. Responses are reported in minutes per day over the past seven days.	18 months
Visual Analogue Scales ("Bubbles")	Visual Analogue Scale with 'Bubbles', 4 self-report items represented by bubbles of increasing size, indicating different levels of general stress and symptom-related distress.	During the intervention (12 weeks)
BORG-RPE-Scale	Self-report rating scale of perceived exertion that quantifies the subjective intensity of physical effort during activity. The scale ranges from 6 ("no exertion") to 20 ("maximal exertion").	During the intervention (12 weeks)

Collaborators and Investigators

• Sponsor: Charite University, Berlin, Germany

Publications and helpful links

General Publications

• Tobelmann L, Hahne I, Schulze T, Bergmann N, Fuchs L, Zierhut M, Hahn E, Boge K. Mechanisms of action and processes of yoga-based group intervention for inpatients with schizophrenia spectrum disorders-A longitudinal qualitative study. Front Psychiatry. 2023 Feb 7;14:1086468. doi: 10.3389/fpsyt.2023.1086468. eCollection 2023.
• Hahne I, Zierhut M, Bergmann N, Hahn E, Ta TMT, Calvano C, Bajbouj M, Boge K. Yoga-Based Group Intervention for Inpatients with Schizophrenia Spectrum Disorders-Feasibility, Acceptability, and Preliminary Outcomes of a Rater-Blinded Randomized Controlled Trial. Schizophr Bull. 2026 Jan 16;52(1):sbae198. doi: 10.1093/schbul/sbae198.

Study record dates

Study Major Dates

• Study Start (Estimated): March 1, 2026
• Primary Completion (Estimated): September 1, 2027
• Study Completion (Estimated): March 1, 2028

Study Registration Dates

• First Submitted: March 3, 2026
• First Submitted That Met QC Criteria: March 3, 2026
• First Posted (Actual): March 6, 2026

Study Record Updates

• Last Update Posted (Actual): March 11, 2026
• Last Update Submitted That Met QC Criteria: March 9, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Schizophrenia Spectrum and Other Psychotic Disorders; Mental Disorders; Psychotic Disorders; Therapeutics
• Other Study ID Numbers: YOGIA

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