The effectiveness of mandala coloring on the psychological and physiological symptoms in adult hospitalized patients: a meta-analysis.

Background

Hospitalization often imposes a dual burden of psychological and physiological challenges that can adversely affect patients’ recovery and overall quality of life [ 1 , 2 ]. On the psychological side, uncertainty about the course of illness, disruption of daily routines, and the loss of personal autonomy frequently give rise to anxiety, stress, and depressive symptoms. At the same time, physiological symptoms such as pain, fatigue, nausea, and sleep disturbances are common, either as direct consequences of the underlying condition or as side effects of treatment [ 2 , 3 ]. Although pharmacological treatments are commonly used to alleviate symptoms such as pain, nausea, or anxiety, their effectiveness can be limited and may sometimes be accompanied by side effects or interactions [ 4 , 5 ]. For this reason, there has been increasing interest in supportive, non-pharmacological approaches that can help address patients’ psychological and physiological needs without adding to the pharmacological burden. Among these, creative and art-based methods have attracted attention for their potential to promote relaxation, enhance emotional regulation, and contribute to overall well-being in both healthy populations and patients [ 6 – 10 ].

Among the wide range of creative interventions, mandala coloring has received growing attention as a simple yet structured practice that can foster psychological stability [ 11 , 12 ]. The act of coloring within repetitive, geometric designs is thought to promote attentional focus, mindfulness, and emotional regulation, thereby reducing anxiety and stress while enhancing positive affect [ 13 , 14 ]. Unlike other forms of art therapy that often require trained therapists or extensive resources, mandala coloring is inexpensive, requires minimal supervision, and can be easily implemented at bedside [ 15 ]. These characteristics make it a particularly feasible option for hospitalized patients, offering a non-invasive strategy that can complement conventional care.

To date, systematic reviews and meta-analyses evaluating mandala coloring have been limited in number and scope. Existing syntheses have largely concentrated on psychological outcomes, particularly anxiety, and often did not extend their analyses to other relevant domains such as pain, fatigue, or physiological indicators [ 16 , 17 ]. Moreover, several reviews have combined different populations, including healthy adults, children, and individuals with trauma-related conditions, thereby restricting the applicability of their conclusions to hospitalized adults [ 17 – 19 ]. These methodological and population-related limitations have hindered the ability to draw comprehensive and generalizable conclusions. Consequently, there remains a need for a rigorous meta-analytic synthesis that evaluates both psychological and physiological symptoms of mandala coloring in hospitalized adults while also exploring potential sources of heterogeneity through subgroup analyses.

The aim of this meta-analysis was to quantitatively synthesize the evidence on the effectiveness of mandala coloring interventions in hospitalized adults across psychological and physiological symptoms. By addressing the methodological limitations of previous reviews and incorporating findings from randomized controlled trials (RCTs) and controlled clinical trials (CCTs), this study seeks to provide a more comprehensive understanding of the therapeutic potential of mandala coloring in clinical populations.

Methods

Design

The present study was conducted as a meta-analysis. The reporting process was structured in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (Supplementary File 1). To ensure methodological transparency, the study protocol was prospectively registered in the International Prospective Register of Systematic Reviews (PROSPERO) (CRD420251130565).

Search strategy

A comprehensive literature search was independently carried out by two authors between 14 and 22 August 2025, without applying language restrictions. The following electronic databases were examined: PubMed, Web of Science, Cochrane Library, CINAHL, PsycINFO, Embase, Scopus, and national databases (ULAKBIM and the Turkish Higher Education Thesis Database) to identify studies evaluating the effects of mandala coloring interventions in adult hospitalized patients.

The search strategy combined free-text keywords and controlled vocabulary terms related to mandala-based interventions (e.g., mandala coloring/painting/drawing, mandala art, mandala therapy, art-based mandala coloring), target populations (e.g., adult inpatients, hospitalized patients, surgical patients, medical patients), and relevant psychological and physiological symptoms (e.g., stress, anxiety, depression, well-being, hope, fatigue, pain, nausea, comfort). Boolean operators (AND, OR), truncation, and database-specific subject headings (e.g., MeSH in PubMed, CINAHL Headings, EMTREE in Embase) were used as appropriate. Detailed search strategies adapted for each database are presented in Supplementary File 2.

In addition, reference lists of included articles and related systematic reviews were manually screened to identify further eligible studies. Grey literature sources, including national theses and dissertations, were also searched. Any discrepancies in the search or study selection process were resolved through discussion, with consultation from an external reviewer when necessary.

Inclusion and exclusion criteria

The eligibility criteria for this systematic review were formulated in accordance with the PICOS framework, which considers Participants (P), Interventions (I), Comparators (C), Outcomes (O), and Study designs (S). This structured approach ensured a transparent and rigorous process for selecting studies relevant to the review objectives [ 20 ]. The detailed inclusion and exclusion criteria are summarized in Table 1 . Both RCTs and CCTs were included to provide a comprehensive synthesis of the available evidence, particularly given the limited number of randomized studies in this emerging field. Regarding outcomes, anxiety and stress in this study refer to situational psychological responses to hospitalization rather than clinical anxiety disorders (e.g., generalized anxiety disorder, panic disorder, phobias) or chronic stress conditions (e.g., episodic, environmental).

Table 1 Inclusion and exclusion criteria based on PICOS framework PICOS Elements Inclusion criteria Exclusion criteria Participants (P) Adult hospitalized patients (≥ 18 years) admitted for any medical or surgical condition. Pediatric or adolescent patients (< 18 years); outpatients or community-dwelling individuals; healthcare professionals, caregivers, or healthy volunteers. Intervention (I) Mandala coloring delivered as a stand-alone intervention, individually or in groups, in paper-based or digital formats during hospitalization. Art-based interventions not specifically focused on mandala coloring (e.g., free drawing, general art therapy); mandala combined with other interventions (e.g., mandala + music vs. control). Comparators (C) Usual care (standard medical and nursing care), no intervention. Studies without a control/comparison group, or comparing two active mandala-based interventions directly. Outcomes (O) Psychological outcomes (e.g. stress, anxiety, depression, hope, well-being); physiological outcomes (nausea, pain, fatigue, comfort). Studies not reporting any psychological or physiological outcomes. Study Designs (S) RCTs and CCTs with pre- and post-test measurement with a control group Qualitative studies, observational studies, reviews, conference abstracts, case studies, case reports, editorials or opinion articles. RCT Randomized controlled trials, CCT Controlled clinical trials

Study selection and data extraction

All titles and abstracts retrieved through the search process were independently assessed by two authors. Duplicate references were identified and removed using Mendeley Reference Manager. In cases where either reviewer judged a record to be potentially relevant, the full text was obtained for further evaluation. Any discrepancies in study selection were resolved through discussion, and consultation with an external reviewer was sought when consensus could not be achieved. Additionally, inter-rater agreement was assessed using Cohen’s kappa, yielding values of 0.91 for title/abstract screening and 0.88 for full-text evaluation, indicating almost perfect agreement.

For data extraction, the Cochrane Collaboration’s standardized form entitled “Data collection form for intervention reviews: RCTs and non-RCTs” was employed [ 21 ]. The form was pilot tested with three randomly selected studies, and minor revisions were applied to enhance clarity and contextual relevance. Extracted information included: study characteristics (authors, year, country, language, design), participant details (sample size, age, gender), eligibility criteria, intervention characteristics (format of mandala coloring, facilitator, setting, frequency, duration, delivery method, content), comparator conditions, symptom measures (psychological and physiological symptoms, assessment tools, timing of assessments), methodological features (power analysis, intention-to-treat application), as well as adverse events, funding sources, and conflict of interest declarations. When data were missing or unclear, study authors were contacted for clarification.

Quality assessment

The methodological quality and potential risk of bias of the included studies were independently evaluated by two authors using the Cochrane Risk of Bias (RoB) tool [ 22 ]. The tool considers seven domains: random sequence generation, allocation concealment, blinding of participants and personnel, blinding of outcome assessment, incomplete outcome data, selective reporting, and other potential sources of bias. Each domain was rated as low, unclear, or high risk of bias according to the criteria outlined in the Cochrane Handbook.

Disagreements between reviewers were resolved through discussion, and if consensus was not achieved, an external reviewer was consulted. All judgments were made strictly on the basis of information available in the published reports, supplemented by study protocols or trial registrations when such sources were accessible.

Certainty of evidence

The overall certainty of evidence for each outcome was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach [ 23 ]. This framework evaluates the confidence in pooled estimates across five domains: risk of bias, inconsistency, indirectness, imprecision, and other considerations (e.g., publication bias). Because the meta-analysis included both RCTs and CCTs, the initial level of evidence was determined according to the predominant study design contributing to each outcome. All evaluations were performed using the GRADEpro Guideline Development Tool.

Data synthesis

All statistical analyses were performed using Review Manager (RevMan, version 5.4). When essential data were missing, study authors were contacted for clarification; if no response was obtained, available data were estimated using the RevMan calculator whenever feasible.

For each outcome, pooled effect sizes were expressed as mean difference (MD) when studies applied identical measurement tools, or as standardized mean difference (SMD) when different scales were used. SMDs were evaluated using Cohen’s rule of thumb, whereby values around 0.2 indicate a small effect, values around 0.5 indicate a moderate effect, and values of 0.8 or above indicate a large effect [ 24 ]. All estimates were reported with 95% confidence intervals (CIs). In studies with multiple intervention or control arms, the data were split to avoid double-counting participants in the meta-analysis. When repeated measures were reported, the last post-intervention score was used for analysis.

Between-study heterogeneity was evaluated using Cochran’s Q test and Higgins’ I² statistic. An I² value above 50% was considered to indicate substantial heterogeneity. Random-effects models were employed when heterogeneity was significant, while fixed-effect models were applied otherwise. A p-value < 0.05 was deemed statistically significant. Results were illustrated using forest plots. When ten or more studies were available for an outcome, publication bias was examined visually through funnel plots.

We conducted subgroup analyses according to session frequency (single [SS] vs. multiple sessions [MS]) and intervention duration (≤ 30 vs. > 30 min) to evaluate the potential influence of intervention characteristics. These subgroup analyses were specified a priori, given the clinical and theoretical relevance of intervention dose in psychosocial therapies.

A sensitivity analysis was conducted by separating RCTs from CCTs to examine the robustness of the pooled estimates and evaluate the potential influence of study design on effect sizes.

Quantitative syntheses, including overall and subgroup meta-analyses, were conducted only when at least two eligible studies reported the same outcome. In cases where fewer than two studies were available, findings were described narratively.

Results

Study selection

The study selection process is illustrated in Fig. 1 . A total of 523 records were identified through database searches (PubMed, Embase, Scopus, Cochrane Library, Web of Science, PsycINFO, CINAHL, ULAKBIM, and the Turkish Thesis Database), and an additional 58 records were retrieved from grey literature and other sources. After the removal of 342 duplicates, 181 records remained for screening. Following title and abstract screening, 138 records were excluded as they did not meet the eligibility criteria. The full texts of the remaining 43 reports were assessed for eligibility, of which 34 were excluded for not meeting the inclusion criteria. Ultimately, 9 studies from database searches and 8 from other sources were included, yielding a total of 17 studies in the qualitative and quantitative syntheses.

Fig. 1 PRISMA flow diagram of study selection process

Study characteristics

Table 2 summarizes 17 studies (8 RCTs, 9 CCTs) published between 2018 and 2025 and conducted in Türkiye ( n = 7; S5, S6, S9, S12, S13, S15, S17), Iran ( n = 4; S2, S3, S14, S16), China ( n = 2; S4, S11), Egypt ( n = 2; S7, S8), South Korea ( n = 1; S1), and India ( n = 1; S10).

Table 2 Characteristics of included studies Study Author(s), year, country Design Sample size Female % Patient group Outcome(s) Tool(s) S1 Kim et al., 2018 [ 25 ], South Korea CCT -Exp: 15 -Control: 13 60.7% Psychiatric -Well-being -Resilience -Hope -Concise Measure of Subjective Well-Being -Resilience Scale -Schizophrenia Hope Scale-9 (SHS-9) S2 Barati et al., 2020 [ 26 ], Iran CCT -Exp: 15 -Control: 15 50% Multiple sclerosis -Stress -Anxiety -Depression Anxiety Stress Scale (DASS-21) S3 Khademi et al., 2021 [ 27 ], Iran RCT -Exp: 35 -Control: 35 45.7% COVID-19 patients -Anxiety -State-Trait Anxiety Inventory (STAI) S4 Zhou et al., 2021 [ 28 ], China CCT -Exp: 30 -Control: 30 81.7% Surgical -Mood (fidgety, pain and sadness, happiness and excitement) -Physiological parameters (heart rate, systolic/diastolic BP) -Waiting time -Chinese Mood Adjective Checklist S5 Akbulat & Can, 2023 [ 29 ], Turkiye CCT -Exp: 41 -Control: 43 100.0% Breast cancer -Anxiety -State-Trait Anxiety Inventory (STAI) S6 Karagöz, 2023 [ 32 ], Turkiye RCT -Exp: 11 -Control: 13 45.8% Hematologic cancer -Fatigue -Sleep quality -Brief Fatigue Scale -Pittsburg Sleep Quality Index (PUKI) S7 Mohamed et al., 2023a [ 30 ], Egypt CCT -Exp: 31 -Control: 31 58.0% Hemodialysis -Anxiety -State-Trait Anxiety Inventory (STAI) S8 Mohamed et al., 2023b [ 31 ], Egypt CCT -Exp: 31 -Control: 31 58.0% Hemodialysis -Resilience -The Connor-Davidson Resilience Scale (CD-RISC) S9 Akyol, 2024, Turkiye RCT -Exp: 21 -Control: 21 100.0% Gynecological oncology -Pain -Anxiety -Visual Analog Scale (VAS) -State-Trait Anxiety Inventory (STAI) S10 Çelik & Kin, 2024 [ 34 ], India RCT -Exp: 19 -Control: 19 68.4% Various cancer types -Nausea -Vomiting -Comfort -MASCC Antiemesis Tool -General Comfort Scale Short Form S11 Mengqin et al., 2024 [ 36 ], China CCT -Exp: 59 -Control: 59 100.0% Gynecological cancer -Anxiety -Stress -Hope -Self-acceptence -Pain -Satisfaction -Physiological parameters (pulse, systolic/diastolic BP) -Waiting time -State-Trait Anxiety Inventory (STAI) -Visual Analog Scale (VAS) -Herth Hope Index (HHI) -Self-Acceptance Questionnaire (SAQ) -Visual Analog Scale (VAS) -Visual Analog Scale (VAS) S12 Kırıcı, 2024 [ 35 ], Turkiye RCT -Exp: 49 -Control: 49 32.6% Hemodialysis -Comfort -Hemodialysis Comfort Scale Version- II S13 Özer et al., 2024 [ 37 ], Turkiye CCT -Exp: 30 -Control: 30 66.0% Hemodialysis -Fatigue -Well-being -Coping -Fatigue Severity Scale (FSS) -Psychological Well-Being Scale (PWBS) -Ways of Coping Questionnaire (WCQ) S14 Sadeqi et al., 2024 [ 38 ], Iran RCT -Exp: 30 -Control: 30 NR Burn -Pain -Anxiety -Visual Analog Scale (VAS) -Burn Specific Pain Anxiety Scale (BSPAS) S15 Üçeriz & Bölüktaş, 2025 [ 39 ], Turkiye RCT -Exp: 23 -Control: 23 50.0% Hematologic cancer -Anxiety -Hopelessness -Stress -Well-being -State-Trait Anxiety Inventory (STAI) -Beck’s Hopelessness Scale -Distress Thermometer -Psychological Well-Being Scale (PWBS) S16 Dadashi et al., 2025 [ 40 ], Iran CCT -Exp: 35 -Control: 35 100.0% Breast cancer -Quality of life (physical functioning, role functioning, emotional functioning, cognitive functioning, social functioning, global health status, fatigue, pain, dyspnea, appetite loss, insomnia, nausea/vomiting, constipation, diarrhea, and financial difficulties) -European Organization for Research and Treatment of Cancer QoL Questionnaire (EORTC QLQ-C30) S17 Oğul, 2025 [ 41 ], Turkiye RCT -Exp: 16 -Control: 19 54.3% Hemodialysis -Anxiety -Depression -Hospital Anxiety and Depression Scale (HADS) RCT Randomized controlled trial, CCT Controlled clinical trials, Exp Experimental, NR Not reported, BP Blood pressure

Across studies, the total sample was 987 participants (range 24–118 per study). The proportion of female participants ranged from 32.6% (S12) to 100% (e.g., S5, S9, S11, S16); one study did not report gender distribution (S14). Clinical populations included oncology (breast or gynecologic: S5, S9, S11, S14, S16; hematologic: S6, S15; various cancer: S10), hemodialysis (S7, S8, S12, S13, S17), psychiatry (S1), multiple sclerosis (S2), COVID-19 (S3), burn (S14), and surgical settings (S4).

The most frequently evaluated symptoms were anxiety (e.g., S2, S3, S5, S7, S9, S11, S14, S15, S17), stress (S2, S11, S15), well-being (S1, S13, S15), hopelessness/hope (S1, S11, S15), pain (S4, S9, S11, S14), comfort (S10, S12), resilience (S1, S8), nausea/vomiting (S10, S16), vital parameters (heart rate, blood pressure [BP]; S4, S11); additional outcomes included sleep quality (S6), coping (S13), satisfaction and waiting time (S11, S4), and multi-domain mood (S4) or quality of life (S16). The State-Trait Anxiety Inventory (STAI) was the most frequently applied tool for anxiety (S3, S5, S7, S9, S11, S15). Pain, stress and satisfaction were often measured using the Visual Analogue Scale (VAS) (S9, S11, S14). The Psychological Well-Being Scale (PWBS) was employed for well-being (S13, S15) (Table 2 ).

Most interventions employed mandala coloring ( n = 10; S2, S3, S5, S6, S7, S8, S10, S13, S14, S17), followed by mandala art therapy ( n = 4; S1, S11, S12, S16) (Table 3 ). Interventions were predominantly researcher-led ( n = 15; S2–S10, S12–S17), while two were delivered by clinical/mandala-therapy personnel or teams (S1, S11). Delivery was face-to-face in all studies; format was individual in nearly all ( n = 15; S3–S17).

Table 3 Characteristics of mandala interventions Study code Author(s), Year Intervention name Provider Setting Session(s) Frequency Duration Timing Delivery Content/Components Comparator S1 Kim et al., 2018 [ 25 ] Mandala art therapy Nurse and Mandala art therapist Neuropsychiatric wards 8 Bi-weekly, 8 weeks 60 min/session During the day Face-to-face, group * Mandala patterns * Colored pencils * Crayons SC S2 Barati et al., 2020 [ 26 ] Mandala coloring software Researcher NR 12 3x/week, one month NR During the day Face-to-face, group * Mandala designs coloring software * Mobile phones SC S3 Khademi et al., 2021 [ 27 ] Mandala coloring Researcher Internal medicine and infectious disease wards 6 1x/day, 6 days 30 min/session In the hospital/in the evening Face-to-face, individual * Six preselected mandala drawings (different for each day) * A pack of six coloured pencils (yellow, blue, green, red, purple, and brown) SC S4 Zhou et al., 2021 [ 28 ] Mandala painting Researcher Preparation room in operating 1 1x/before surgery 20 min Just before surgery Face-to-face, individual * Ten preselected mandala drawings (The patient chose one of them) * Colored pencils SC S5 Akbulat & Can, 2023 [ 29 ] Mandala coloring Researcher CT unit 1 1x/first CT 30 min Receiving CT for the first time Face-to-face, individual * Mandala coloring book * Laptop table used as a painting stand * 12 colored markers SC S6 Karagöz, 2023 [ 32 ] Mandala coloring Researcher Hematology wards 7 1x /day, one week 30 min In the hospital/in the evening Face-to-face, individual * Seven preselected round-shaped mandala drawings (different for each day) * 12 colored pencils SC S7 Mohamed et al., 2023a [ 30 ] Mandala coloring Researcher HD unit 6 2x /week 45–60 min NR Face-to-face, individual * Pre-designed mandalas SC S8 Mohamed et al., 2023b [ 31 ] Mandala coloring Researcher HD unit 6 2x/week 45–60 min NR Face-to-face, individual * Pre-designed mandala * Coloring pencils * Eraser SC S9 Akyol, 2024 Mandala activity Researcher Gynecological oncology surgery clinic 3 1x/day, 3 days (postop day 0, 1, 2) 60 min In the hospital/during the day Face-to-face, individual * A booklet of 10 mandala drawings (The patient chose one of them) * 12 Colored pencils SC S10 Çelik & Kin, 2024 [ 34 ] Mandala coloring Researcher CT unit 1 1x/CT 30 min During CT Face-to-face, individual * Mandala coloring book * Laptop table used as a painting stand * Crayons SC S11 Mengqin et al., 2024 [ 36 ] Mandala art therapy Mandala art therapy team: 2 counseling-trained, 3 mandala-certified University women and children hospital 3 1x/day, 3 days (before surgery, postop day 2 or day 3) 30–40 min Perioperative period Face-to-face, individual * Colored pencils with 36 colors * A4 picture books * Erasers SC S12 Kırıcı, 2024 [ 35 ] Mandala art therapy Mandala certified researcher HD unit 8 In 8 consecutive HD sessions 30 min During HD Face-to-face, individual * “Mandala Booklet”, which consists of eight structured mandala patterns with round shapes and contains general information about mandalas. * Colored pencils SC S13 Özer et al., 2024 [ 37 ] Mandala coloring Researcher Dialysis unit 8 1x/week, 8 weeks 2 h During HD Face-to-face, individual * Eight preselected mandala drawings were printed on separate pieces of A4 paper (different for each day) * 12 colored pencils (red, orange, yellow, pink, light green, green, sky blue, blue, purple, brown, red brown, and black) SC S14 Sadeqi et al., 2024 [ 38 ] Mandala coloring Researcher Burn unit 1 1 30 min Before dressing changes Face-to-face, individual * Pre-selected mandala pattern * 12 colored pencils SC S15 Üçeriz & Bölüktaş, 2025 [ 39 ] Art-based Mandala Researcher Allogeneic and autologous transplant unit 7 1x/day, one week 30 min Before, during, after transplant Face-to-face, individual * Mandala coloring papers * 12 colored dry paints, crayons, and felt-tip crayons SC S16 Dadashi et al., 2025 [ 40 ] Mandala art therapy Researcher Oncology and radiotherapy wards 6 1x/day, 6 days 45 min Started in unit, continued at home Face-to-face, individual * 6 pre-selected mandala patterns printed separately on A4 sheets * 6 colored pencils (yellow, blue, green, red, orange, and brown) SC S17 Oğul, 2025, Türkiye [ 41 ] Mandala coloring Mandala-trained researcher HD unit 8 2x/week, 4 weeks 30 min During HD Face-to-face, individual * Practice table * Structured mandala templates * 12-color crayons * Eraser * Sharpener SC CT Chemotherapy, HD Hemodialysis, Postop Postoperative, SC Standard care

Settings were hospital-based and varied: hemodialysis/dialysis units ( n = 5; S7, S8, S12, S13, S17), CT units (S5, S10), oncology/gynecologic oncology/radiotherapy services (S9, S16), hematology (S6), internal medicine/infectious disease wards (S3), neuropsychiatry (S1), operating preparation room (S4), burn unit (S14), and bone marrow transplant unit (S15). Intervention “dose” ranged from 1 to 12 sessions. Six-session (S3, S7, S8, S11, S16) and eight-session formats (S1, S12, S13, S17) were most common; single-session protocols were used peri-procedurally (S4, S5, S10, S14), with additional three- (S9), seven- (S6, S15), and twelve-session designs (S2) (Table 3 ).

Content commonly comprised pre-selected mandala templates (often round patterns) and coloring media (frequently 6–12 colored pencils/markers); several studies used structured booklets or A4 sheets, with practical aids (e.g., laptop/practice tables in S5, S10, S17). One study implemented a mobile mandala-coloring software (S2) (Table 3 ). None of the included studies documented adverse events related to mandala coloring, and the intervention was consistently reported as safe and well accepted by participants.

Risk of bias

The risk of bias assessment for the included studies is summarized in Figs. 2 and 3 . Overall, the majority of studies demonstrated either high or unclear risk in at least one domain, with the most frequent concerns related to allocation concealment, performance bias, and blinding of outcome assessment [ 25 – 41 ]. The following provides detailed considerations for each domain:

Fig. 2 Risk of bias graph

Fig. 3 Risk of bias summary

Random sequence generation (selection bias)

Several studies adequately described randomization methods, such as computer-generated sequences or random number tables, and were rated as low risk [ 26 , 27 , 32 , 33 , 35 , 38 , 39 ]. However, other trials provided insufficient detail or applied quasi-experimental approaches, resulting in judgments of high risk.

Allocation concealment (selection bias)

Most studies did not use or report sufficient details regarding concealment procedures (e.g., sealed opaque envelopes, central randomization), and thus were rated as high or unclear risk [ 25 – 33 , 35 – 41 ]. Only one study described robust allocation concealment strategies [ 34 ].

Blinding of participants and personnel (performance bias)

Given the nature of mandala coloring interventions, blinding of participants and facilitators was generally not feasible. Consequently, all studies were judged to be at high risk of performance bias.

Blinding of outcome assessment (detection bias)

This domain was frequently rated as high or unclear risk because outcomes were primarily self-reported (e.g., stress, anxiety, pain, fatigue, well-being). In most cases, outcome assessors were not blinded. A small number of studies attempted partial blinding, such as involving independent analysts [ 32 , 39 ].

Incomplete outcome data (attrition bias)

Most studies were rated as low risk for attrition bias, as dropout rates were minimal and adequately reported, and intention-to-treat analyses were performed where appropriate.

Selective reporting (reporting bias)

All studies were judged to be at low risk of selective reporting, as prespecified outcomes were reported consistently in line with study objectives. In particular, studies with registered protocols demonstrated clear alignment between planned and reported outcomes [ 27 , 34 , 37 – 39 ].

Other bias

This domain was assessed according to the reporting of baseline characteristics, data collection procedures, funding sources, sample size justifications, and conflict of interest declarations. Studies were judged as unclear risk if one of these elements was missing and as high risk when more than one was absent. While most studies provided sufficient methodological transparency, others were rated as unclear or high risk due to one or more unreported items.

Certainty of the evidence

The certainty of evidence ranged from low to very low across outcomes. Anxiety was supported by low-certainty evidence, whereas most psychological and physiological outcomes were supported by very low-certainty evidence due to risk of bias, heterogeneity, and imprecision. No high-certainty evidence was identified. Detailed GRADE assessments are presented in the Supplementary File 3.

Effects of mandala coloring on psychological symptoms

Anxiety

As presented in Fig. 4 , the meta-analysis of nine studies (5 RCTs, 4 CCTs) revealed a significant large effect of mandala coloring in reducing anxiety compared to control groups (SMD = − 2.16, 95% CI [–3.38, − 0.95], p = 0.0005; I² = 97%).

Subgroup analysis revealed that interventions with a duration of ≤ 30 min significantly reduced anxiety compared with control (SMD = − 1.62, 95% CI [–3.02, − 0.22], p = 0.02; I² = 96%), whereas those lasting > 30 min did not show a significant effect (SMD = − 3.20, 95% CI [–6.57, 0.18], p = 0.06; I² = 98%). Similarly, multiple-session interventions were associated with significant reductions in anxiety (SMD = − 2.40, 95% CI [–3.91, − 0.88], p = 0.002; I² = 97%), while single-session interventions demonstrated no significant effects (SMD = − 1.38, 95% CI [–4.02, 1.26], p = 0.31; I² = 97%) (Fig. 4 ).

Fig. 4 Overall and subgroup effects of mandala interventions on anxiety

Stress

The pooled analysis of three studies demonstrated a significant reduction in stress levels among participants in the mandala coloring groups compared with control (SMD = − 2.45, 95% CI [–3.06, − 1.85], p < 0.00001; I² = 50%) (Fig. 5 ).

Fig. 5 Effects of mandala interventions on stress

Other psychological symptoms (well-being, hope, and resilience)

As shown in Fig. 6 , the meta-analysis of three studies (1 RCT, 2 CCTs) revealed that mandala coloring significantly improved well-being compared with control (SMD = 4.51, 95% CI [0.81, 8.21], p = 0.02; I² = 97%). For hope, two studies demonstrated a significant positive small effect in favor of mandala coloring (SMD = 0.42, 95% CI [0.09, 0.75], p = 0.01; I² = 0%). However, the pooled analysis of two studies assessing resilience did not show a significant effect (SMD = 2.45, 95% CI [–2.28, 7.18], p = 0.31; I² = 98%).

Fig. 6 Effects of mandala interventions on other psychological symptoms

Effects of mandala coloring on physiological symptoms

Pain

As presented in Fig. 7 , the meta-analysis of five studies (2 RCTs, 3 CCTs) found no significant effect of mandala coloring on pain symptoms compared to control (SMD = − 0.35, 95% CI [–1.18, 0.47], p = 0.40; I² = 92%).

Fig. 7 Overall and subgroup effects of mandala interventions on pain

Subgroup analysis showed no significant effects for interventions lasting ≤ 30 min (SMD = − 1.03, 95% CI [–3.78, 1.72], p = 0.46; I² = 98%) or > 30 min (SMD = 0.02, 95% CI [–0.44, 0.48], p = 0.94; I² = 65%). Similarly, multiple-session (SMD = 0.02, 95% CI [–0.44, 0.48], p = 0.94; I² = 65%) and single-session interventions (SMD = − 1.03, 95% CI [–3.78, 1.72], p = 0.46; I² = 98%) did not demonstrate statistically significant effects on pain symptoms (Fig. 7 ).

Fatigue

The pooled analysis of three studies (1 RCT, 2 CCTs) suggested a reduction in fatigue in the mandala coloring groups; however, the effect was not statistically significant (SMD = − 3.09, 95% CI [–6.60, 0.42], p = 0.08; I² = 98%) (Fig. 8 ).

Fig. 8 Effects of mandala interventions on fatigue

Other physiological symptoms (nausea, comfort, and vital parameters)

The pooled analysis of two studies (1 RCT, 1 CCT) found no significant effect of mandala coloring on nausea (SMD = − 0.08, 95% CI [–0.45, 0.30], p = 0.69; I² = 0%). Similarly, no significant differences were observed for comfort in two included studies (2 RCTs) (SMD = 0.46, 95% CI [–0.03, 0.94], p = 0.06; I² = 43%) (Fig. 9 ).

Fig. 9 Effects of mandala interventions on other physiological symptoms

Mandala coloring did not produce significant effects on vital parameters (2 CCTs for all), including systolic BP (MD = − 0.84, 95% CI [–14.05, 12.38], p = 0.90; I² = 92%), diastolic BP (MD = − 0.75, 95% CI [–9.79, 8.28], p = 0.87; I² = 88%), and pulse (MD = 1.95, 95% CI [–1.55, 5.45], p = 0.27; I² = 52%) (Fig. 9 ).

Sensitivity analysis by study design

Sensitivity analyses were conducted only for outcomes with a sufficient number of RCTs to evaluate the robustness of the pooled estimates after excluding CCTs. For anxiety, the pooled analysis restricted to RCTs continued to demonstrate a statistically significant reduction in anxiety levels (SMD = − 2.03, 95% CI [–3.33, − 0.74], p = 0.002; I² = 94%). For pain, the sensitivity analysis including only RCTs showed no statistically significant difference between the mandala coloring and control groups (SMD = − 0.93, 95% CI [–3.89, 2.02], p = 0.54; I² = 98%). Forest plots of the sensitivity analyses are presented in Supplementary File 4.

Discussion

This meta-analysis evaluated the effects of mandala coloring interventions on psychological and physiological symptoms in hospitalized adult populations. Among the evaluated outcomes, anxiety demonstrated the most consistent and methodologically supported evidence. The pooled analysis revealed a significant reduction in anxiety, and sensitivity analyses restricted to RCTs produced comparable effect estimates, supporting the robustness of this finding and suggesting that the observed benefit was not primarily driven by non-randomized study designs. Stress also showed a significant reduction; however, the smaller number of available studies positions this outcome as supportive rather than confirmatory evidence. For other symptoms, including well-being, hope, fatigue, resilience, comfort, nausea, and physiological parameters, meta-analyses were feasible but were generally based on a limited number of studies, often with few randomized trials. This constraint reduces the reliability and generalizability of these findings and warrants cautious interpretation. Notably, sensitivity analysis for pain similarly demonstrated no statistically significant effect after restricting the analysis to randomized trials, supporting the stability of the observed lack of effect while also suggesting that the current evidence base may be underpowered to detect clinically meaningful differences. When interpreted through the GRADE framework, the overall certainty of evidence ranged from low to very low, indicating that these findings should be interpreted cautiously despite the observed effects.

Heterogeneity was substantial across most analyses, likely reflecting the clinical and methodological diversity of the included studies. Variations in patient populations (e.g., oncology, surgical, psychiatric, dialysis settings), intervention protocols (session duration, frequency, and format), outcome measurement tools, and study designs may all have contributed to the observed variability. Importantly, high heterogeneity is frequently reported in meta-analyses evaluating complex psychosocial and art-based interventions, where contextual and implementation factors inherently influence outcomes [ 16 – 19 ]. Notably, the very large effect sizes observed for certain psychological outcomes, particularly anxiety and well-being, should be interpreted with caution in light of this substantial heterogeneity. Clinical diversity, small sample sizes, non-blinded outcome assessment, and the inclusion of non-randomized designs may have contributed to amplified pooled estimates. Although subgroup analyses explored selected intervention characteristics, residual heterogeneity remained, indicating that pooled estimates should be interpreted cautiously and may not be uniformly generalizable across clinical contexts. However, these subgroup findings should be interpreted cautiously, as multiple comparisons may increase the risk of type I error. Future RCTs should prioritize methodological standardization, including clearly defined intervention protocols, consistent outcome measures, and adequately powered samples, to enhance comparability across studies and reduce unexplained variability. The substantial variability in intervention characteristics also highlights the need for greater standardization in future trials. Developing structured intervention frameworks, such as clearly defined session length and frequency, appropriate timing within the care process, facilitator training, and consistent use of coloring materials, may enhance reproducibility and improve comparability across studies. Greater protocol consistency would ultimately support more precise estimates of intervention effectiveness.

Consistent with prior research on art-based and mindfulness-oriented interventions, mandala coloring appears to produce psychological benefits [ 42 – 44 ]. However, the very large effect sizes observed in some outcomes should be interpreted with caution, as methodological factors such as small sample sizes and lack of blinding may have contributed to effect inflation. The significant improvements in anxiety, stress, well-being, and hope align with the premise that structured coloring promotes attentional focus, facilitates mindfulness, and creates a state of relaxation through rhythmic and repetitive engagement [ 45 , 46 ]. Similar benefits of mandala coloring and related art-therapy approaches have been reported among diverse groups including students [ 10 , 47 ], pediatric patients [ 48 , 49 ], adolescents [ 50 , 51 ], caregivers [ 15 , 52 ], and working professionals [ 53 ]. These findings highlight the capacity of mandala-based interventions to buffer emotional distress, foster positive affect, and provide patients with a sense of agency during hospitalization. Subgroup analysis demonstrated that shorter sessions (≤ 30 min) delivered repeatedly were particularly effective in reducing anxiety. Clinically, this finding suggests that mandala coloring can be delivered in brief, structured formats that are feasible within routine hospital care. Mechanistically, concise sessions may reduce cognitive strain, while repetition may support emotional regulation. Such an interpretation aligns with mindfulness evidence showing that short but repeated practice alleviates anxiety [ 54 ], as well as art-based intervention studies in older adults reporting a dose–response effect favoring frequent repetition over extended single sessions [ 44 ]. These results underscore the importance of systematically examining intervention dose and structure in future trials to support the development of standardized protocols. Notably, longer sessions (> 30 min) and single-session interventions did not yield statistically significant effects on anxiety, which may reflect reduced engagement or insufficient exposure to achieve meaningful psychological change. In contrast to anxiety, subgroup analyses for pain revealed no significant effects regardless of session duration or frequency. This discrepancy may be attributed to the multifactorial nature of pain, which is shaped by biological, pharmacological, and psychosocial factors that brief art-based interventions may not sufficiently address [ 55 ]. These findings suggest that while mandala coloring appears to be a promising approach for psychological symptoms, its applicability to physiological outcomes may require longer intervention periods or integration with multimodal treatment strategies.

Regarding physiological symptoms, the meta-analyses did not demonstrate significant effects of mandala coloring on pain, fatigue, nausea, or vital parameters. These findings should be interpreted in light of the complex and multifactorial nature of physical symptoms. Pain and fatigue are influenced by disease severity, pharmacological management, and comorbidities, which may outweigh the potential impact of a brief art-based intervention [ 55 ]. Evidence from a pilot mindfulness-based art therapy trial in cancer outpatients similarly demonstrated that while psychological and spiritual well-being improved, physical symptoms including pain and fatigue remained largely unaffected [ 56 ]. Nausea is likewise shaped by complex physiological and treatment-related mechanisms that may not be sufficiently altered by short-term psychological approaches [ 57 , 58 ]. Vital parameters, including blood pressure and pulse, are inherently variable and highly sensitive to situational and environmental influences, making them less suitable for detecting subtle regulatory changes [ 59 ]. The absence of significant physiological effects may also reflect inconsistencies in outcome measurement and the relatively short duration of many interventions, which may have limited the ability to detect meaningful biological changes. Establishing standardized physiological endpoints and incorporating longer intervention periods in future trials may improve measurement sensitivity and enhance comparability across studies. Furthermore, evidence for some physiological outcomes relied primarily on non-randomized studies, further limiting certainty. Taken together, while the psychological benefits of mandala coloring, particularly for anxiety, appear relatively consistent, the effects on physiological outcomes remain uncertain. Larger, rigorously designed RCTs incorporating objective physiological indicators, such as heart rate variability (HRV), cortisol levels, inflammatory markers, or other biomarkers, are needed to provide a more comprehensive understanding of the potential biological mechanisms underlying mandala coloring and to determine whether its benefits extend beyond psychological domains.

Strengths and limitations

This meta-analysis has several important strengths. It was prospectively registered in PROSPERO, conducted in accordance with PRISMA guidelines, and based on a comprehensive search strategy covering multiple international and national databases. Both RCTs and CCTs were included, allowing for a broader synthesis of the available evidence. Furthermore, the study evaluated a wide range of psychological and physiological symptoms, thus providing a multidimensional perspective on the potential effects of mandala coloring interventions in hospitalized patients. Sensitivity analyses were conducted for outcomes with a sufficient number of randomized trials, which strengthened confidence in the robustness of the primary findings.

Nonetheless, some limitations should be acknowledged. The number of included studies was small for several symptoms, particularly fatigue, resilience, comfort, and nausea, which may have reduced the statistical power of pooled analyses. Considerable heterogeneity was observed across studies in terms of patient populations (oncology, dialysis, surgical, psychiatric, burn care), intervention protocols (session length, number, frequency, coloring format), delivery modes, and outcome measurement instruments. Such diversity likely influenced the consistency of effect sizes and complicates the interpretation of pooled results. Although subgroup and sensitivity analyses were performed, meta-regression and outlier analyses were not feasible due to the limited number of studies per outcome, and therefore, residual heterogeneity could not be fully explained. Additionally, as the number of studies for each outcome was below ten, formal assessment of publication bias using funnel plots was not feasible, in accordance with established recommendations. The inclusion of CCTs alongside RCTs may have introduced potential design-related bias, as non-randomized studies are inherently more vulnerable to selection bias and residual confounding. Due to the participatory nature of mandala coloring, blinding of participants and facilitators was not feasible, leading to a high risk of performance bias across all studies. This methodological constraint is inherent in art-based and psychosocial interventions and should be considered when interpreting the results. Additionally, the majority of included studies were conducted in Türkiye and Iran, which may introduce regional bias and limit the generalizability of the findings to broader multicultural healthcare settings. Cultural factors may influence patients’ perceptions of art-based interventions, their level of emotional engagement, and their willingness to participate, potentially affecting observed outcomes. Therefore, the results should be interpreted within their cultural context, and further research across diverse geographic and cultural settings is needed to strengthen the cross-context applicability of these findings. Furthermore, the included studies did not consistently report whether data were collected in private or public healthcare settings, limiting the ability to examine potential differences in patient outcomes across healthcare contexts. Finally, although SMDs were used to account for differences in measurement tools, pooling across diverse psychological instruments (e.g., different stress or anxiety scales) may have introduced conceptual heterogeneity and affected interpretability. Furthermore, several pooled outcomes yielded unusually large effect sizes that may have been influenced by methodological characteristics, including small sample sizes, lack of blinding, and the inclusion of non-randomized designs, potentially leading to overestimation of intervention effects.

Implications for clinical practice and research

The findings of this meta-analysis suggest that mandala coloring may represent a feasible supportive approach for addressing psychological distress in hospitalized adults, particularly in relation to anxiety and stress. As a safe, low-cost, and culturally adaptable activity, it has the potential to complement conventional care when psychological support is indicated. However, these implications should be interpreted cautiously given the heterogeneity of the included studies and the limited number of high-quality randomized trials. At present, the evidence is insufficient to support definitive clinical recommendations or standardized implementation.

From a research perspective, the results underscore the need for rigorously designed, multicenter RCTs with larger and more diverse samples to strengthen the evidence base. Future investigations should prioritize the development of standardized intervention protocols, evaluate optimal session frequency and duration, and incorporate objective physiological measures such as cortisol or HRV to better capture the multidimensional impact of mandala coloring. Additionally, studies examining patient selection and contextual factors may further support the development of evidence-informed clinical frameworks.

Conclusion

This meta-analysis suggests that mandala coloring may serve as a supportive intervention for alleviating psychological distress in hospitalized adults, with the most consistent evidence observed for reductions in anxiety and, to a lesser extent, stress. Evidence for other psychological outcomes, such as well-being and hope, remains limited due to the small number of available studies. As a simple and low-cost approach, mandala coloring may complement routine care when psychological support is needed. However, the evidence for physiological outcomes such as pain, fatigue, nausea, comfort, and vital parameters remains limited and inconclusive, largely due to the small number of available studies and the absence of long-term follow-up. Therefore, these findings should be interpreted cautiously and should not yet be broadly generalized to clinical practice. Larger, methodologically rigorous RCTs incorporating sensitive physiological measures are required to determine whether the benefits of mandala coloring extend beyond psychological domains.

Supplementary Information

Supplementary Material 1

Supplementary Material 2

Supplementary Material 3

Supplementary Material 4

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Acknowledgements

Not applicable.

Meta-analysis registration

CRD420251130565.

Authors’ contributions

SP: Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Project administration; Supervision; Validation; Visualization; Roles/Writing - original draft; and Writing - review & editing. ÖED: Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Supervision; Validation; Visualization; Roles/Writing - original draft; and Writing - review & editing.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Data availability

The data supporting the findings of this study are available within the included articles.

Declarations

Ethics approval and consent to participate

As this research synthesized data exclusively from previously published studies, no direct involvement of human participants occurred. Consequently, approval from an institutional ethics committee was not necessary for the conduct of this systematic review and meta-analysis.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Abbreviations

Blood Pressure

Controlled Clinical Trial

Confidence Interval

Cumulative Index to Nursing and Allied Health Literature

Grading of Recommendations Assessment, Development and Evaluation

Heart Rate Variability

Mean Difference

Multiple Sessions

Participants, Interventions, Comparators, Outcomes, Study designs

Preferred Reporting Items for Systematic Reviews and Meta-Analyses

International Prospective Register of Systematic Reviews

Psychological Well-Being Scale

Randomized Controlled Trial

Review Manager

Risk of Bias

Standardized Mean Difference

Single Session

State-Trait Anxiety Inventory

Visual Analogue Scale

References

1. Jespersen KV Hansen MH Vuust P The effect of music on sleep in hospitalized patients: A systematic review and meta-analysis Sleep Health 2023 9 4 441 8 10.1016/j.sleh.2023.03.004 37380591 Jespersen KV, Hansen MH, Vuust P. The effect of music on sleep in hospitalized patients: A systematic review and meta-analysis. Sleep Health. 2023;9(4):441–8. 37380591 10.1016/j.sleh.2023.03.004

2. Newland P Bettencourt BA Effectiveness of mindfulness-based art therapy for symptoms of anxiety, depression, and fatigue: A systematic review and meta-analysis Complement Ther Clin Pract 2020 41 101246 10.1016/j.ctcp.2020.101246 33075726 Newland P, Bettencourt BA. Effectiveness of mindfulness-based art therapy for symptoms of anxiety, depression, and fatigue: A systematic review and meta-analysis. Complement Ther Clin Pract. 2020;41:101246. 33075726 10.1016/j.ctcp.2020.101246

3. Miller CR Patmon FL Knapp H Music to reduce stress in hospitalized patients Nurs 2021 51 6 62 6 10.1097/01.NURSE.0000757168.77552.58 34347757 Miller CR, Patmon FL, Knapp H. Music to reduce stress in hospitalized patients. Nurs. 2021;51(6):62–6. 10.1097/01.NURSE.0000757168.77552.58 34347757

4. Zhang MQ Liu X Huang Y Does Mandala Art Improve Psychological Well-Being in Patients? A Systematic Review J Integr Complement Med 2024 30 1 25 36 10.1089/jicm.2022.0780 37668598 PMC10801676 Zhang MQ, Liu X, Huang Y. Does Mandala Art Improve Psychological Well-Being in Patients? A Systematic Review. J Integr Complement Med. 2024;30(1):25–36. 37668598 10.1089/jicm.2022.0780 PMC10801676

5. Huang W Luan T Li L Zhang A Mu Y Sun Y Huang K Qin R Liu W Guo H The effects of visual art therapy on improving anxiety symptoms in adults: A systematic review and meta-analysis J Psychiatr Ment Health Nurs 2025 32 7 1197 210 10.1111/jpm.70003 40704973 Huang W, Luan T, Li L, Zhang A, Mu Y, Sun Y, Huang K, Qin R, Liu W, Guo H. The effects of visual art therapy on improving anxiety symptoms in adults: A systematic review and meta-analysis. J Psychiatr Ment Health Nurs. 2025;32(7):1197–210. 40704973 10.1111/jpm.70003

6. Morison L Simonds L Stewart SF Effectiveness of creative arts-based interventions for treating children and adolescents exposed to traumatic events: a systematic review of the quantitative evidence and meta-analysis Arts Health 2022 14 3 237 62 10.1080/17533015.2021.2009529 34969356 Morison L, Simonds L, Stewart SF. Effectiveness of creative arts-based interventions for treating children and adolescents exposed to traumatic events: a systematic review of the quantitative evidence and meta-analysis. Arts Health. 2022;14(3):237–62. 34969356 10.1080/17533015.2021.2009529

7. Wang J Zhang B Yahaya R Abdullah AB Colors of the mind: a meta-analysis of creative arts therapy as an approach for post-traumatic stress disorder intervention BMC Psychol 2025 13 32 10.1186/s40359-025-02361-4 39799380 PMC11725198 Wang J, Zhang B, Yahaya R, Abdullah AB. Colors of the mind: a meta-analysis of creative arts therapy as an approach for post-traumatic stress disorder intervention. BMC Psychol. 2025;13:32. 39799380 10.1186/s40359-025-02361-4 PMC11725198

8. Frasco E Sherr L Dedios Sanguineti MC Vera San Juan N Burgess R The impact of creative arts-based interventions for mental health in conflict-affected contexts: a systematic narrative review SSM Ment Health 2025 7 100419 10.1016/j.ssmmh.2025.100419 Frasco E, Sherr L, Dedios Sanguineti MC, Vera San Juan N, Burgess R. The impact of creative arts-based interventions for mental health in conflict-affected contexts: a systematic narrative review. SSM Ment Health. 2025;7:100419.

9. Van Lith T Ettenberger M Arts-based therapies, practices, and interventions in health BMC Complement Med Ther 2023 23 351 10.1186/s12906-023-04177-4 37794363 PMC10548758 Van Lith T, Ettenberger M. Arts-based therapies, practices, and interventions in health. BMC Complement Med Ther. 2023;23:351. 37794363 10.1186/s12906-023-04177-4 PMC10548758

10. Ramos Salazar L Exploring the effect of coloring mandalas on students’ math anxiety in business statistics courses Bus Manag Econ Eng 2019 17 2 134 51 Ramos Salazar L. Exploring the effect of coloring mandalas on students’ math anxiety in business statistics courses. Bus Manag Econ Eng. 2019;17(2):134–51.

11. Nasiri MA Sajadi SA Farsi Z Heidarieh M The effect of mandala coloring and free coloring on the happiness in veterans with post-traumatic stress disorder in the Covid-19 pandemic: a randomized clinical trial BMC Psychiatry 2024 24 467 10.1186/s12888-024-05886-x 38918742 PMC11197346 Nasiri MA, Sajadi SA, Farsi Z, Heidarieh M. The effect of mandala coloring and free coloring on the happiness in veterans with post-traumatic stress disorder in the Covid-19 pandemic: a randomized clinical trial. BMC Psychiatry. 2024;24:467. 38918742 10.1186/s12888-024-05886-x PMC11197346

12. Özsavran M Ayyıldız TK The effect of mandala art therapy on the comfort and resilience levels of mothers who have children with special needs: a randomized controlled study Child Care Health Dev 2023 49 7 1032 45 10.1111/cch.13110 36878873 Özsavran M, Ayyıldız TK. The effect of mandala art therapy on the comfort and resilience levels of mothers who have children with special needs: a randomized controlled study. Child Care Health Dev. 2023;49(7):1032–45. 36878873 10.1111/cch.13110

13. Choi H Hahm SC Jeon YH Han JW Kim SY Woo JM The effects of mindfulness-based mandala coloring, made in nature, on chronic widespread musculoskeletal pain: randomized trial Healthc (Basel) 2021 9 6 642 10.3390/healthcare9060642 PMC8226655 34071674 Choi H, Hahm SC, Jeon YH, Han JW, Kim SY, Woo JM. The effects of mindfulness-based mandala coloring, made in nature, on chronic widespread musculoskeletal pain: randomized trial. Healthc (Basel). 2021;9(6):642. 10.3390/healthcare9060642 PMC8226655 34071674

14. Chen H Liu C Zhang A Lu WQ Wu K Chiou WK How flow and mindfulness interact with each other in mindfulness-based augmented reality mandala coloring activities Front Psychol 2024 14 1301531 10.3389/fpsyg.2023.1301531 38259530 PMC10801900 Chen H, Liu C, Zhang A, Lu WQ, Wu K, Chiou WK. How flow and mindfulness interact with each other in mindfulness-based augmented reality mandala coloring activities. Front Psychol. 2024;14:1301531. 38259530 10.3389/fpsyg.2023.1301531 PMC10801900

15. Ghorbani Z Farahani AS Khabazkhoob M Hosseini A Rassouli M Evaluating the effectiveness of mandala coloring on post-operative anxiety in mothers of children undergoing congenital anomaly surgery: a randomized controlled clinical trial J Pediatr Nurs 2025 82 e175 83 10.1016/j.pedn.2025.04.010 40253270 Ghorbani Z, Farahani AS, Khabazkhoob M, Hosseini A, Rassouli M. Evaluating the effectiveness of mandala coloring on post-operative anxiety in mothers of children undergoing congenital anomaly surgery: a randomized controlled clinical trial. J Pediatr Nurs. 2025;82:e175–83. 40253270 10.1016/j.pedn.2025.04.010

16. Støre SJ Jakobsson N The effect of mandala coloring on state anxiety: a systematic review and meta-analysis Art Ther 2022 39 3 173 81 10.1080/07421656.2021.2003144 Støre SJ, Jakobsson N. The effect of mandala coloring on state anxiety: a systematic review and meta-analysis. Art Ther. 2022;39(3):173–81.

17. Zhang B Wang J Abdullah AB The effects of art therapy interventions on anxiety in children and adolescents: a meta-analysis Clin (Sao Paulo) 2024 79 100404 10.1016/j.clinsp.2024.100404 PMC11260852 38936289 Zhang B, Wang J, Abdullah AB. The effects of art therapy interventions on anxiety in children and adolescents: a meta-analysis. Clin (Sao Paulo). 2024;79:100404. 10.1016/j.clinsp.2024.100404 PMC11260852 38936289

18. Maddox GA Bodner GE Christian MW Williamson P On the effectiveness of visual arts therapy for traumatic experiences: a systematic review and meta-analysis Clin Psychol Psychother 2024 31 5 e3041 10.1002/cpp.3041 39120099 Maddox GA, Bodner GE, Christian MW, Williamson P. On the effectiveness of visual arts therapy for traumatic experiences: a systematic review and meta-analysis. Clin Psychol Psychother. 2024;31(5):e3041. 39120099 10.1002/cpp.3041

19. Joschko R Klatte C Grabowska WA Roll S Berghöfer A Willich SN Active visual art therapy and health outcomes: a systematic review and meta-analysis JAMA Netw Open 2024 7 4 e2428709 10.1001/jamanetworkopen.2024.28709 39264631 PMC11393726 Joschko R, Klatte C, Grabowska WA, Roll S, Berghöfer A, Willich SN. Active visual art therapy and health outcomes: a systematic review and meta-analysis. JAMA Netw Open. 2024;7(4):e2428709. 39264631 10.1001/jamanetworkopen.2024.28709 PMC11393726

20. Amir-Behghadami M Janati A Population, intervention, comparison, outcomes and study (PICOS) design as a framework to formulate eligibility criteria in systematic reviews Emerg Med J 2020 37 7 387 10.1136/emermed-2020-209567 32253195 Amir-Behghadami M, Janati A. Population, intervention, comparison, outcomes and study (PICOS) design as a framework to formulate eligibility criteria in systematic reviews. Emerg Med J. 2020;37(7):387. 32253195 10.1136/emermed-2020-209567

21. Higgins JPT, Green S, editors. Cochrane Handbook for Systematic Reviews of Interventions. Wiley; 2011.

22. Higgins JP Altman DG Gøtzsche PC Jüni P Moher D Oxman AD Savovic J Schulz KF Weeks L Sterne JA Cochrane Bias Methods Group; Cochrane Statistical Methods Group The Cochrane Collaboration’s tool for assessing risk of bias in randomised trials BMJ 2011 343 d5928 10.1136/bmj.d5928 22008217 PMC3196245 Higgins JP, Altman DG, Gøtzsche PC, Jüni P, Moher D, Oxman AD, Savovic J, Schulz KF, Weeks L, Sterne JA, Cochrane Bias Methods Group; Cochrane Statistical Methods Group. The Cochrane Collaboration’s tool for assessing risk of bias in randomised trials. BMJ. 2011;343:d5928. 22008217 10.1136/bmj.d5928 PMC3196245

23. Prasad M Introduction to the GRADE tool for rating certainty in evidence and recommendations Clin Epidemiol Glob Health 2024 25 101484 10.1016/j.cegh.2023.101484 Prasad M. Introduction to the GRADE tool for rating certainty in evidence and recommendations. Clin Epidemiol Glob Health. 2024;25:101484.

24. Cohen J A power primer Psychol Bull 1992 112 1 155 9 10.1037/0033-2909.112.1.155 19565683 Cohen J. A power primer. Psychol Bull. 1992;112(1):155–9. 19565683 10.1037//0033-2909.112.1.155

25. Kim H Kim S Choe K Kim JS Effects of mandala art therapy on subjective well-being, resilience, and hope in psychiatric inpatients Arch Psychiatr Nurs 2018 32 2 167 73 10.1016/j.apnu.2017.08.008 29579508 Kim H, Kim S, Choe K, Kim JS. Effects of mandala art therapy on subjective well-being, resilience, and hope in psychiatric inpatients. Arch Psychiatr Nurs. 2018;32(2):167–73. 29579508 10.1016/j.apnu.2017.08.008

26. Barati F Sarchahi Z Hajebi Khaniki S Baradaran Sirjani E Taghiabadi M Effect of software-based therapeutic coloring on stress and anxiety in patients with multiple sclerosis: a quasi-experimental study Ro J Neurol 2020 19 4 262 7 10.37897/RJN.2020.4.7 Barati F, Sarchahi Z, Hajebi Khaniki S, Baradaran Sirjani E, Taghiabadi M. Effect of software-based therapeutic coloring on stress and anxiety in patients with multiple sclerosis: a quasi-experimental study. Ro J Neurol. 2020;19(4):262–7.

27. Khademi F Rassouli M Rafiei F The effect of mandala colouring on anxiety in hospitalized COVID-19 patients: a randomized controlled clinical trial Int J Ment Health Nurs 2021 30 5 1437 44 10.1111/inm.12901 34143568 PMC8447083 Khademi F, Rassouli M, Rafiei F, et al. The effect of mandala colouring on anxiety in hospitalized COVID-19 patients: a randomized controlled clinical trial. Int J Ment Health Nurs. 2021;30(5):1437–44. 34143568 10.1111/inm.12901 PMC8447083

28. Zhou S Wei L Wang Z Effect of painting intervention based on Mandala-self theory on mood and physiological state in patients in preoperative waiting room Zhong Nan Da Xue Xue Bao Yi Xue Ban 2021 46 3 293 9 33927077 10.11817/j.issn.1672-7347.2021.190795 PMC10929928 Zhou S, Wei L, Wang Z, et al. Effect of painting intervention based on Mandala-self theory on mood and physiological state in patients in preoperative waiting room. Zhong Nan Da Xue Xue Bao Yi Xue Ban. 2021;46(3):293–9. 33927077 10.11817/j.issn.1672-7347.2021.190795 PMC10929928

29. Akbulak F Can G Effectiveness of mandala coloring in reducing anxiety in women with early-stage breast cancer receiving chemotherapy for the first time Explore (NY) 2023 19 1 42 7 10.1016/j.explore.2022.04.007 35508427 Akbulak F, Can G. Effectiveness of mandala coloring in reducing anxiety in women with early-stage breast cancer receiving chemotherapy for the first time. Explore (NY). 2023;19(1):42–7. 35508427 10.1016/j.explore.2022.04.007

30. Mohamed AF Mohamed KA Abou-Abdo SE Effect of mandala coloring nurse-led intervention program on anxiety among hemodialysis patients Int J Novel Res Healthc Nurs 2023 10 2 71 83 Mohamed AF, Mohamed KA, Abou-Abdo SE. Effect of mandala coloring nurse-led intervention program on anxiety among hemodialysis patients. Int J Novel Res Healthc Nurs. 2023;10(2):71–83.

31. Mohamed AF AbouAbdou SE Mohammed KA Effect of mandala coloring nurse-led intervention program on resilience among hemodialysis patients Trends Nurs Health Care J 2023 7 3 209 21 Mohamed AF, AbouAbdou SE, Mohammed KA. Effect of mandala coloring nurse-led intervention program on resilience among hemodialysis patients. Trends Nurs Health Care J. 2023;7(3):209–21.

32. Karagöz F. The effect of mandala coloring on fatigue and sleep quality in hematology patients receiving chemotherapy [master’s thesis]. Bursa: Bursa Uludağ University, Institute of Health Sciences; 2023.

33. Akyol S. The effect of mandala activity on postoperative pain and anxiety levels in gynecological oncology patients [master’s thesis]. Istanbul: Üsküdar University, Institute of Health Sciences; 2024.

34. Çelik A Kin ÖK Clinical trial of mandala coloring for management of chemotherapy-induced nausea and vomiting Altern Ther Health Med 2024 30 2 13 7 39565703 Çelik A, Kin ÖK. Clinical trial of mandala coloring for management of chemotherapy-induced nausea and vomiting. Altern Ther Health Med. 2024;30(2):13–7. 39565703

35. Kırıcı G. The effect of mandala art therapy on comfort level in patients receiving hemodialysis treatment [master’s thesis]. Gaziantep: Sanko University, Institute of Graduate Education; 2024.

36. Mengqin Z Xing L Yan H Jianhua R Does mandala art therapy improve psychological well-being of gynecological cancer patients during the perioperative period? a quasi-experimental study Integr Cancer Ther 2024 23 15347354241259180 10.1177/15347354241259180 38845365 PMC11159551 Mengqin Z, Xing L, Yan H, Jianhua R. Does mandala art therapy improve psychological well-being of gynecological cancer patients during the perioperative period? a quasi-experimental study. Integr Cancer Ther. 2024;23:15347354241259180. 38845365 10.1177/15347354241259180 PMC11159551

37. Özer Z Bahçecioğlu Turan G Uyman M Mollaoğlu M The effects of mandala coloring on fatigue, psychological well-being, and coping with stress in patients receiving hemodialysis treatment Hemodial Int 2024 28 3 367 76 10.1111/hdi.13163 38898367 Özer Z, Bahçecioğlu Turan G, Uyman M, Mollaoğlu M. The effects of mandala coloring on fatigue, psychological well-being, and coping with stress in patients receiving hemodialysis treatment. Hemodial Int. 2024;28(3):367–76. 38898367 10.1111/hdi.13163

38. Sadeqi H Rahzani K Hekmatpou D Rakei Isfahani S The effect of adult coloring (mandala pattern) on pain and anxiety associated with dressing changes in burn patients: a randomized controlled trial Scars Burn Heal 2024 10 20595131231218062 10.1177/20595131231218062 38343526 PMC10854211 Sadeqi H, Rahzani K, Hekmatpou D, Rakei Isfahani S. The effect of adult coloring (mandala pattern) on pain and anxiety associated with dressing changes in burn patients: a randomized controlled trial. Scars Burn Heal. 2024;10:20595131231218062. 38343526 10.1177/20595131231218062 PMC10854211

39. Üçeriz AÇ Bölüktaş RP The effect of art-based mandala on mental health among patients transplanting bone marrow: a randomized controlled study Mediterr Nurs Midwifery 2025 5 2 102 13 10.4274/MNM.2024.24248 Üçeriz AÇ, Bölüktaş RP. The effect of art-based mandala on mental health among patients transplanting bone marrow: a randomized controlled study. Mediterr Nurs Midwifery. 2025;5(2):102–13.

40. Dadashi N Khanali Mojen L Ilkhani M Nasirie M Mirzaee HR Boozaripour M Effect of mandala art therapy on quality of life in breast cancer patients Asian Pac J Cancer Prev 2025 26 7 2533 40 10.31557/APJCP.2025.26.7.2533 40729075 PMC12510120 Dadashi N, Khanali Mojen L, Ilkhani M, Nasirie M, Mirzaee HR, Boozaripour M. Effect of mandala art therapy on quality of life in breast cancer patients. Asian Pac J Cancer Prev. 2025;26(7):2533–40. 40729075 10.31557/APJCP.2025.26.7.2533 PMC12510120

41. Oğul S. The effect of mandala coloring on anxiety and depression in patients undergoing hemodialysis treatment [master’s thesis]. Kars: Kafkas University, Institute of Health Sciences; 2025.

42. Abu-Odah H Sheffield D Hogan S Yorke J Molassiotis A Effectiveness of creative arts therapy for adult patients with cancer: a systematic review and meta-analysis Support Care Cancer 2024 32 430 38874793 10.1007/s00520-024-08582-4 Abu-Odah H, Sheffield D, Hogan S, Yorke J, Molassiotis A. Effectiveness of creative arts therapy for adult patients with cancer: a systematic review and meta-analysis. Support Care Cancer. 2024;32:430. 38874793 10.1007/s00520-024-08582-4

43. Lin J Lin X Chen Q Li Y Chen WT Huang F The effects of art-making intervention on mind-body and quality of life in adults with cancer: a systematic review and meta-analysis Support Care Cancer 2024 32 186 38396058 10.1007/s00520-024-08364-y Lin J, Lin X, Chen Q, Li Y, Chen WT, Huang F. The effects of art-making intervention on mind-body and quality of life in adults with cancer: a systematic review and meta-analysis. Support Care Cancer. 2024;32:186. 38396058 10.1007/s00520-024-08364-y

44. Quinn EA Millard E Jones JM Group arts interventions for depression and anxiety among older adults: a systematic review and meta-analysis Nat Ment Health 2025 3 374 86 10.1038/s44220-024-00368-1 40084230 PMC11896886 Quinn EA, Millard E, Jones JM. Group arts interventions for depression and anxiety among older adults: a systematic review and meta-analysis. Nat Ment Health. 2025;3:374–86. 40084230 10.1038/s44220-024-00368-1 PMC11896886

45. Liu C Chen H Liu CY Lin RT Chiou WK Cooperative and individual mandala drawing have different effects on mindfulness, spirituality, and subjective well-being Front Psychol 2020 11 564430 10.3389/fpsyg.2020.564430 33162908 PMC7581735 Liu C, Chen H, Liu CY, Lin RT, Chiou WK. Cooperative and individual mandala drawing have different effects on mindfulness, spirituality, and subjective well-being. Front Psychol. 2020;11:564430. 33162908 10.3389/fpsyg.2020.564430 PMC7581735

46. Shukla P Jain J Review paper on mandala as a mindfulness tool and its consequent implications on stress management and improved focus Educ Adm Theory Pract 2024 30 5 7639 45 Shukla P, Jain J. Review paper on mandala as a mindfulness tool and its consequent implications on stress management and improved focus. Educ Adm Theory Pract. 2024;30(5):7639–45.

47. Duong K Stargell NA Mauk GW Effectiveness of coloring mandala designs to reduce anxiety in graduate counseling students J Creat Ment Health 2018 13 3 318 30 10.1080/15401383.2018.1437001 Duong K, Stargell NA, Mauk GW. Effectiveness of coloring mandala designs to reduce anxiety in graduate counseling students. J Creat Ment Health. 2018;13(3):318–30.

48. Moharamkhani M Rassouli M Khanali Mojen L Respini D Aghebati A Ashrafizadeh H Assessing effects of mandala painting on anxiety of 9–14-year-old children with cancer Adv Integr Med 2023 10 1 8 14 10.1016/j.aimed.2023.02.002 Moharamkhani M, Rassouli M, Khanali Mojen L, Respini D, Aghebati A, Ashrafizadeh H. Assessing effects of mandala painting on anxiety of 9–14-year-old children with cancer. Adv Integr Med. 2023;10(1):8–14.

49. Shahrbabaki RM Omidi A Shaterian N Makarem Z Effectiveness of mandala coloring intervention on children’s preoperative anxiety: a randomized clinical trial study in Iran Iran J Nurs Midwifery Res 2025 30 4 421 5 10.4103/ijnmr.ijnmr_23_24 40520405 PMC12164774 Shahrbabaki RM, Omidi A, Shaterian N, Makarem Z. Effectiveness of mandala coloring intervention on children’s preoperative anxiety: a randomized clinical trial study in Iran. Iran J Nurs Midwifery Res. 2025;30(4):421–5. 40520405 10.4103/ijnmr.ijnmr_23_24 PMC12164774

50. Fan X Hui ANN Academic stress and burnout reduction through mandala-coloring and grit-enhancing: school-based interventions for adolescents Behav Sci (Basel) 2025 15 4 439 10.3390/bs15040439 40282061 PMC12024132 Fan X, Hui ANN. Academic stress and burnout reduction through mandala-coloring and grit-enhancing: school-based interventions for adolescents. Behav Sci (Basel). 2025;15(4):439. 40282061 10.3390/bs15040439 PMC12024132

51. Emanuela C, Satiadarma MP, Roswiyani R. The effectiveness of coloring in reducing anxiety and improving PWB in adolescents. IAFOR J Arts Humanit. 2021;8(1):35-48.

52. Karabuga Yakar H Yılmaz B Çelik E Özkol O Gevher F Oruc Ö Şen H The effect of the meditation based mandala programme on distress, anxiety and depression in the caregivers of cancer patients in palliative care unit Omega (Westport) 2023 87 1–2 1361 74 10.1177/00302228231181936 37280745 Karabuga Yakar H, Yılmaz B, Çelik E, Özkol O, Gevher F, Oruc Ö, Şen H. The effect of the meditation based mandala programme on distress, anxiety and depression in the caregivers of cancer patients in palliative care unit. Omega (Westport). 2023;87(1–2):1361–74. 37280745 10.1177/00302228231181936

53. Priya V Gayatridevi S Efficacy of mandala art in social anxiety, emotion regulation and mental well-being among working professionals J Indian Acad Appl Psychol 2024 50 2 111 7 Priya V, Gayatridevi S. Efficacy of mandala art in social anxiety, emotion regulation and mental well-being among working professionals. J Indian Acad Appl Psychol. 2024;50(2):111–7.

54. Strohmaier S Jones FW Cane JE Effects of length of mindfulness practice on mindfulness, depression, anxiety, and stress: a randomized controlled experiment Mindfulness 2021 12 1 198 214 10.1007/s12671-020-01512-5 Strohmaier S, Jones FW, Cane JE. Effects of length of mindfulness practice on mindfulness, depression, anxiety, and stress: a randomized controlled experiment. Mindfulness. 2021;12(1):198–214.

55. Raudenská J Šteinerová V Vodičková Š Arts therapy and its implications in chronic pain management: a narrative review Pain Ther 2023 12 3 1309 37 10.1007/s40122-023-00542-w 37733173 PMC10616022 Raudenská J, Šteinerová V, Vodičková Š, et al. Arts therapy and its implications in chronic pain management: a narrative review. Pain Ther. 2023;12(3):1309–37. 37733173 10.1007/s40122-023-00542-w PMC10616022

56. Meghani SH Peterson C Kaiser DH A pilot study of a mindfulness-based art therapy intervention in outpatients with cancer Am J Hosp Palliat Care 2018 35 9 1195 200 10.1177/1049909118760304 29514486 Meghani SH, Peterson C, Kaiser DH, et al. A pilot study of a mindfulness-based art therapy intervention in outpatients with cancer. Am J Hosp Palliat Care. 2018;35(9):1195–200. 29514486 10.1177/1049909118760304

57. Singh P Yoon SS Kuo B Nausea: a review of pathophysiology and therapeutics Ther Adv Gastroenterol 2016 9 1 98 112 10.1177/1756283X15618131 26770271 PMC4699282 Singh P, Yoon SS, Kuo B. Nausea: a review of pathophysiology and therapeutics. Ther Adv Gastroenterol. 2016;9(1):98–112. 26770271 10.1177/1756283X15618131 PMC4699282

58. Nainis N Paice JA Ratner J Wirth JH Lai J Shott S Relieving symptoms in cancer: innovative use of art therapy J Pain Symptom Manage 2006 31 2 162 9 10.1016/j.jpainsymman.2005.07.006 16488349 Nainis N, Paice JA, Ratner J, Wirth JH, Lai J, Shott S. Relieving symptoms in cancer: innovative use of art therapy. J Pain Symptom Manage. 2006;31(2):162–9. 16488349 10.1016/j.jpainsymman.2005.07.006

59. Parati G Stergiou GS Dolan E Bilo G Blood pressure variability: clinical relevance and application J Clin Hypertens (Greenwich) 2018 20 7 1133 7 10.1111/jch.13304 30003704 PMC8030809 Parati G, Stergiou GS, Dolan E, Bilo G. Blood pressure variability: clinical relevance and application. J Clin Hypertens (Greenwich). 2018;20(7):1133–7. 30003704 10.1111/jch.13304 PMC8030809