Canine-Assisted Therapy in Reducing Stress and Anxiety Levels of University Students: Systematic Review and Meta-analysis of Randomized Controlled Trials

doi:10.21203/rs.3.rs-4568343/v1

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Systematic Review

Canine-Assisted Therapy in Reducing Stress and Anxiety Levels of University Students: Systematic Review and Meta-analysis of Randomized Controlled Trials

https://doi.org/10.21203/rs.3.rs-4568343/v1

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Background

Due to the high prevalence of mental health issues among university students worldwide, canine-assisted therapy (CAT) has emerged as a potential intervention to reduce student stress and anxiety. This study systematically reviews and meta-analyzes the effects of CAT on reducing stress and anxiety levels among university students.

Methods

A systematic search was conducted across multiple databases for randomized controlled trials (RCTs) published in English and Chinese including Google Scholar, Duke Libraries, APA PsychNet, PubMed, CNKI, and Wanfang, focusing on RCTs. Only studies utilizing professionally trained dogs and handlers in therapy sessions were included. Data were extracted independently by two reviewers (SS and ZL), and the risk of bias was assessed using the Cochrane Risk-of-Bias tool. Effect sizes (Hedges’ g) were pooled for individual outcomes using random-effects meta-analysis. Statistical analyses, including subgroup analyses examining the impact of intervention duration, were conducted to determine the overall effect size and explore potential moderators.

Results

Thirteen RCTs met the inclusion criteria, involving interventions with varying durations and control conditions. The meta-analysis revealed a statistically significant overall effect size of d = -0.703 (p < 0.001), indicating a moderate reduction in stress and anxiety levels among university students. However, high heterogeneity was observed across studies (I² = 71.77, p < 0.001), suggesting variability in intervention effectiveness.

Conclusion

CAT demonstrates promise in alleviating stress and anxiety among university students. Despite methodological variations and potential publication bias, the findings suggest that CAT may offer a feasible and accessible approach to enhancing mental well-being within university environments. Further studies are necessary to examine factors influencing methodological diversity and refine the integration of CAT within university settings.

Systematic Review

Meta-Analysis

Canine-Assisted Therapy

University Students

Stress level

Anxiety level

Randomized Controlled Trials

Discussions are increasingly highlighting a growing crisis in student mental health [1]. In just 2021 alone, approximately 73% of students reported persistent psychological distress, a significant increase since 2013, reflecting a 50% rise in mental health challenges within this population [2]. The causes of these mental health issues include academic workload pressure, loneliness, inadequate sleep, and being away from family [3]. Subsequently, prolonged stress exposure could catalyze the emergence of more severe mental health illnesses, increasing the anxiety rate within the university student population [4].

In response to the impact of stress on both academic performance and overall well-being, universities have introduced various stress reduction interventions such as mindfulness programs, peer support groups, and on-campus counseling sessions [5–6]. However, the effectiveness of these interventions is inconsistent due to underutilization and low uptake by students. Peer support may deter students from disclosing personal issues to other students, while mindfulness programs face operational challenges, such as resource allocation and comprehensive training, which involve added costs and efforts [7–8]. On-campus counseling services are also strained under high demand, leading to long waiting times for students and increased counselor burnout and turnover [9]. Clinical interventions require qualified trainers and rely on student engagement and willingness to participate, which can limit their reach and impact [10]. Given these considerations, there is a need for an intervention that is less resource-intensive, accessible, and convenient for students, making canine-assisted therapy a promising option.

Canine-assisted therapy is a complementary intervention using professionally trained dogs to enhance individuals’ physical, social, emotional, or cognitive functioning [11–12]. Therapy dogs and their handlers undergo specialized training to ensure that interactions are beneficial and secure [12]. Often referred to as humans’ best friends, therapy dogs have been successfully incorporated into various settings, including nursing homes, hospitals, and schools, tailored to diverse populations [13]. Even briefly interacting, such as hugging, petting, and sitting next to therapy dogs, can lower levels of stress hormones like epinephrine and norepinephrine, increase endorphin levels and oxytocin, leading to decreased stress, anxiety, and pain, improve mood, and better social bonding [12]. Recent studies have shown that canine-assisted therapy effectively reduces stress among nurses [14] and enhances the quality of life for Alzheimer's patients [15].

Practically, canine-assisted therapy is also more economical as dogs can be transported with ease and can interact with a larger number of people during a single drop-in session, offering more cost-efficient interaction opportunities [16]. A report indicated that 62% of surveyed universities in the United States provide animal-assisted therapy (AAT) programs, the majority of which exclusively involved dogs [17]. This suggests that canine-assisted therapy is a viable intervention for addressing the escalating mental health concerns in universities, particularly given the high burnout rate among counselors and the financial implications of hiring more professional counselors [9].

Theoretically, canine-assisted therapy (CAT) is based on social support theory, offering a source of social connectedness and combating feelings of loneliness and isolation. Social support, as defined by Thoits [18], refers to the social resources individuals can rely on when dealing with life challenges and stressors. According to this theory, social support has several dimensions. First, social support can be conceptualized as perceived support, reflecting an individual’s belief that support is available when needed [18]. Second, support can take various forms: instrumental, informational, or emotional. CAT primarily provides emotional support, which involves expressions of sympathy, caring, esteem, value, or encouragement [19]. Additionally, such social relationships extend beyond human interactions to encompass connections with animals. As McNicholas and Collis [20] noted, pets can complement existing human support networks and, in some cases, even serve as substitutes for lacking human connections. Pets provide support that releases individuals from relationship obligations, facilitates reorganization, and helps rebuild routines. In this context, CAT presents a unique type of social support that nurtures emotional connection in individuals. Furthermore, having a supportive social network has a direct impact on wellbeing, especially when it is large and is perceived to offer support, which can improve quality of life and reduce stress [21]. Consequently, the dogs and handlers involved in CAT play a crucial role in engaging individuals in social interactions and offering social support, thereby buffering them from stress and anxiety.

Recognizing that heightened stress and anxiety can decrease students’ quality of life and performance [22], CAT emerges as a promising intervention. Yet, there appears to be a gap in meta-analyses of CAT’s effectiveness in reducing stress and anxiety in university settings. To elaborate, we identified the 10 most relevant existing meta-analyses of canine-assisted therapy (Table 1). Among all studies, only one was conducted in university settings [23], while the others consist of various age groups ranging from children [24–25], adolescents [26], the elderly population [27], and the mixing ages [28–32]. While Huber et al. [23] examined the effectiveness of canine-assisted therapy in higher education settings, their analysis primarily focused on general mental, cognitive, and physiological outcomes, with stress and anxiety being only partial components. Additionally, their analysis included broader animal-assisted interventions (AAI), which include various animals beyond dogs, such as cats and fish, diluting the focus solely on therapy dogs.

Therefore, this paper aims to systematically review the effectiveness of canine-assisted therapy in reducing university students’ stress and anxiety levels. Our meta-analysis seeks to fill this gap by evaluating the effectiveness of canine-assisted therapy in reducing stress and anxiety levels specifically for university students. We included only randomized controlled trials (RCTs) to establish a robust cause-and-effect relationship between CAT and its effects. By conducting a systematic review and meta-analysis of randomized controlled trials on canine-assisted therapy in reducing university students’ stress and anxiety levels, we aim to provide substantial evidence of the effectiveness of this intervention in promoting mental wellness among this population.

Table 1

Past Meta-Analyses.
Author, Year	Age Group	Animals Involved	RCTs	CAT
Nimer & Lundahl, 2007	Children (0–12 years), Adolescents (13–17 years), Adults (18–64 years), Elderly (65 + years)	Aquatic Animals, Combination, Dog, Horse, Other	Not specifically for RCT	No (focus on AAT)
Virues-Ortega et al., 2012	Elderly (40 + years)	Aquarium, Bird, Cat, Dog, Dolphin, Ferret, Rabbit	Not specifically for RCT	No (focus on AAT)
Charry-Sánchez et al., 2018	Children	Unknown	Yes	No (focus on AAT)
Germain et al., 2018	Participants (8–62 years) with trauma	Combination, Dog, Horse	Not specifically for RCT	No (focus on AAPT)
Waite et al., 2018	Children and Adults (2–88 years, Mean = 28.15)	Dog	Not only RCTs	Yes
Jones et al., 2019	Adolescents (10–19 years)	Dog	Not specifically for RCT	N (focus on Canine-Assisted Psychotherapy)
Hediger et al., 2021	Participants (4–86 years) with PTSD	Combination, Dog, Dolphin, Farm Animals, Horse, Seal, Sheep	Not specifically for RCT	No (focus on AAI)
Feng et al., 2021	Children and Adolescents (3–17 years)	Dog	Not only (4 RCTs and 4 quasi-experimental studies)	Yes
Zhang et al., 2021	Children (3–18 years)	Dog	Not only (4 RCTs and 3 CCTs)	Yes
Huber et al., 2022	Undergraduate Students (Mean = 20.2 years)	Cat, Dog, Fish	Yes (RCTs and cRCTs)	No (focus on AAI)
Note: Only 1 meta-analysis was identified to be done in university settings; 5 studies included other animals rather than just therapy dogs; 2 studies restricted the analyses to randomized controlled trials only.

PROSPERO Registration

Our systematic review and meta-analyses were developed in accordance with the PRISMA-P 2015 statement [33]. As of June 12th, 2024, our PROSPERO registration record has ID number CRD42024518138.

Types of Participants

This study will include university students (undergraduate and graduate students), encompassing males and females, as well as those who prefer not to disclose their gender. Students clinically diagnosed with anxiety disorders are also eligible for inclusion, as previous research has demonstrated the effectiveness of canine-assisted therapy in treating anxiety [34].

Types of Interventions

Inclusion Criteria

This meta-analysis will exclusively focus on canine-assisted therapy (CAT). However, when conducting an overview of all similar treatments using animal-assisted interventions, we observed a standard confusion in the concept and experimental design of these interventions. Some AAIs use untrained animals and untrained caregivers, while the AAT requires that during the treatment process, the animal must be professionally trained and qualified, and a professional handler must be accompanied [35]. Therefore, for an intervention to be considered CAT in our study, it must have two key criteria: (1) the use of professionally trained dogs certified by relevant organizations; (2) the dog handler must be present during the treatment. If the handler's presence is not mentioned, we assume they are present since that is the typical setting for CAT. With these established criteria, even though some papers might not name the intervention, particularly as canine-assisted therapy, we will still include them in our review as long as the intervention involves trained therapy dogs and professional handlers. Included papers should be written in English or Chinese language.

Exclusion Criteria

Certain similar interventions, such as animal visitation programs (AVPs) and animal-assisted psychotherapy (AAPT), will be excluded. AVPs may involve animals that are not professionally trained [36], which does not meet the requirement of using professionally trained dogs in this study. AAPT typically involves psychotherapists incorporating animals into therapy sessions, primarily focusing on patients with clinically diagnosed mental illnesses [26]. However, university students experiencing stress and anxiety may not necessarily have a clinical diagnosis of a mental illness.

Additionally, some interventions classified under Animal-Assisted Intervention (AAI) will be excluded for two reasons. Firstly, AAI is an umbrella term that broadly includes various fields such as animal-assisted activities (AAA), animal-assisted education (AAE), and animal-assisted therapy (AAT) [37]. Canine-assisted therapy (CAT) falls under the category of AAT, which exclusively utilizes dogs for treatment, whereas AAT may involve various animals such as cats, fish, dolphins, guinea pigs, and birds, among others [27]. This study specifically focuses on interventions involving dogs, hence canine-assisted therapy. Secondly, AAI may involve professionals from diverse fields, including educators, activity coordinators, or volunteers [38], while CAT only involves trained dog handlers. Therefore, interventions that may not necessarily utilize professionally trained animals and handlers will be excluded from this study.

Comparisons

The main comparator in this study will be the control group of students who were not exposed to the canine-assisted therapy intervention. Control group designs may vary across studies, such as waitlist control, only handler control, watching videos about dogs’ control, and completing unrelated tasks.

Outcomes

The primary outcome will be decreases in reported stress and anxiety levels in the group exposed to canine-assisted therapy. Measurement of stress and anxiety levels will be based on established scales or measures utilized in the included studies. According to the American Psychological Association [39], anxiety is defined as “an emotion characterized by feelings of tension, worried thoughts, and physical changes like increased blood pressure”. Meanwhile, stress can be defined as a state of worry or mental tension caused by a difficult situation [40].

Study Design

This study focuses exclusively on experimental studies, particularly randomized controlled trials (RCTs), to establish a causal relationship between the intervention and its effects on students' stress and anxiety levels.

Study Settings

This meta-analysis and systematic review will include studies conducted within university and college settings, given their relevance to the target population of undergraduate and graduate students.

Sources and Search Strategy

We systematically searched Google Scholar, Duke Libraries, APA PsycNet, PubMed, and Chinese databases (CNKI and Wanfang) for articles published from the database inception to April 10, 2024. Reference lists from relevant systematic reviews and included studies were hand-searched for potentially relevant publications.

Our search method included a combination of keyword and subject heading searches. The search string used was as follows:

("canine-assisted therapy" OR "canine therapy" OR CAT OR "dog-assisted therapy" OR "dog therapy" OR "canine-assisted intervention" OR "animal-assisted therapy" OR "animal therapy" OR "animal-assisted intervention" OR AAI) AND (college OR undergraduate OR graduate OR "higher education" OR "university students") AND (stress OR "stress levels" OR anxiety OR "anxiety levels")

We restricted our search terms to experimental studies, randomized controlled trials, and studies published in English and Chinese. Our search concludes as of April 23, 2024, and papers published after this date will not be considered for inclusion.

Data Extraction

Data extraction was completed by both reviewers independently using an Excel sheet. Data were collected on the study design, study participants, the treatment condition, the control condition, and reported outcomes. Conflicts were resolved through regular discussions. There is a checklist developed based on both reviewers’ mutually agreed criteria before selection (Supplementary Material A), disagreement decisions will be resolved based on if the study meets the criteria.

Data Analysis

We conducted a random-effects meta-analysis to pool the effect sizes of the included studies using STATA 18. Subgroup analyses were performed to examine the impact of the duration of the intervention and to compare the effect sizes of studies based on their levels of risk of bias. Heterogeneity across studies was assessed using the I² statistic. Small-study bias was accounted for through Egger’s test, while potential publication bias was evaluated using trim-and-fill analysis and funnel plots.

Study Selection

After searching all databases based on our search strategy, we obtained 57 search results (Fig. 1). We further removed 12 duplicate records before starting the screening process, resulting in 45 articles remaining. Additionally, we attempted to retrieve 8 articles, but only 1 was successfully obtained after contacting all the authors. Following the screening procedure, we narrowed down the articles to 38 for a more thorough assessment of eligibility. During this process, we excluded 25 articles for various reasons, such as not using professionally trained dogs in the intervention. No studies fitting our criteria were identified in the Chinese databases. Further details can be found in the PRISMA flow chart (Fig. 1). This brings the total number of individual studies included in our review to 13 [10, 41–52]. All 13 studies were included in the meta-analyses.

Study Characteristics

Most of the included studies were conducted in Western countries, with 3 studies in Canada, 7 in the USA, and 3 in the UK. Only one study reported students' previous mental illness diagnoses, demonstrating that 33% of participants had previously been diagnosed with anxiety disorders [41]. Across all studies, participants interacted with therapy dogs and handlers simultaneously during the intervention sessions, with interaction durations ranging from 1 minute to 90 minutes. Control conditions varied across studies, including wait-list control [47], watching videos of dogs [46], and completing the Family Life-Space Diagram [10]. While all studies reported reductions in stress and anxiety levels in the intervention group, only one study did not find statistically significant results [10]. Four studies measured the intervention effect through perceived stress levels, 6 studies assessed anxiety levels using the State-Trait Anxiety Inventory, and the remaining measures include the Family Life Space Diagram, Momentary Stress, and PROMIS. Additional details on study designs are provided in the Summary Table of Papers (Table 2), with a summary of each study's results presented in Supplementary Material B.

Table 2

**Summary table of papers (n = 13).** All studies were conducted in Western countries (e.g. Canada, USA, UK). All interventions included students interacting with both dogs and handlers concurrently, while the control design varied in each study.
Paper	Year	Country	Setting/ Context	Sample characteristics	Intervention	Control/ Comparison Group
Anderson & Brown	2021	USA	Bachelor of Science in Nursing Program	N = 89 Male (n = 9), Female (n = 80) Age range = 20–22 Previous Anxiety Diagnosis = 33% of participants	4 dogs and their handlers Treatment condition: The participants completed an interaction with the therapy dogs for 35–45 minutes prior to the medication calculation exam.	Control condition: Participants interacted with each other for 35–45 minutes in a separate and secluded room without dogs present.
Barker et al.	2016	USA	Virginia Commonwealth University	N = 78 (completed one condition), N = 57 (completed both conditions) 76.9% female (n = 60 females, 18 males) Mean age = 19.38, SD = 1.75	10 therapy dogs Treatment condition: Students were permitted to freely interact with any of the dog teams during the 15-minute intervention.	Control condition: Attention-control - completing the Family Life-Space Diagram.
Barker et al.	2017	USA	University counseling center event	N = 74 Primarily white (56.8%) and 75.7% were females (75.7%) Mean age = 19.38, SD = 1.75	10 therapy dogs Treatment condition: Students in small groups interacted with any of the dog teams for 15 minutes	Control condition: Attention-control - completing the Family Life-Space Diagram.
Binfet	2017	Canada	Mid-size western Canadian university	N = 163 78% female Mean age = 18.85, SD = 2.65, Range = 17–49	14 therapy dogs Treatment condition: Interaction with a therapy dog for 20 minutes.	Control condition: Complete a business-as-usual model (i.e., a typical activity undertaken by participants) that had them study information from a course they were currently taking.
Binfet et al.	2021	Canada	Western Canadian University	N = 284 77% female, 21% male, 2% non-binary Mean age = 20.4, SD = 2.38, Range = 17–36	24 therapy dogs Treatment condition: Participants interacted with therapy dogs and were asked to engage in direct physical contact (e.g., caressing or petting the dog) for 20 minutes Treatment condition 2: Participants were in the immediate proximity of a therapy dog but engaged in no physical contact with the dog, we excluded this data from the meta-analysis	Control condition: Only the canine handler (no dogs) were present
Grajfoner et al.	2017	UK	Heriot–Watt University	N = 132 Mostly females (n = 85) Mean age = 21.6, SD = 3.4, Range = 17–34	6 therapy dogs Treatment condition: Participants interacted with both a handler and their dog for 20 mins.	Control condition: Participants interacted with a handler only (HO) Control condition 2: Participants interacted with a dog only (DO), we excluded this data for the meta-analysis
Haefelin et al.	2020	USA	Liberal arts and sciences college in western PA	N = 165 Male (n = 55), Female (n = 108), Other (n = 1), Preferred not to answer (n = 1) Mean age = 19.38, SD = 1.13, Age range = 18–22	1 dog and handler Treatment condition: Participants were asked to interact with the condition for 1 minute.	Control condition: Watch a video on a provided laptop computer that shows dogs being playful.
Kivlen et al.	2022	USA	A large Midwestern university	N = 104 79% female Mean age = 23.72, SD = 2.39	5 therapy dogs Treatment condition: Participants engaged in the CAI (Canine-Assisted Intervention) for 6 weeks in self-identified cohorts of 3 to 5 students, each session lasts for 35 minutes.	Control condition: Students were told that they were on the waitlist and given the option to engage in the intervention after data collection.
Manville et al.	2022	UK	Middlesex University	N = 60 Female (n = 47), Male (n = 13) Mean age = 25.3, SD = 6.99, Range = 19.1–52	1 therapy dog Treatment condition: Participants interact with dog for 10min. Petting and talking to the canine were the most common interactions.	Control condition: A neutral task of watching a PowerPoint presentation with unrelated (non-animal), neutral images for 10 minutes.
Spruin et al.	2020	UK	Local university	N = 94 Male (n = 37), Female (n = 57) Mean age = 22.76, SD = 4.87, Range = 18–46	1 therapy dog Treatment condition: Participants were free to engage with the therapy dog however they wanted for 30 minutes Treatment condition 2: Participants listened to a pre-recorded 30-minute guided mindfulness exercise, consisting of a mindful meditation of the breath, we excluded this data from the meta-analysis	Control condition: The standard treatment for student stress and anxiety at the target university, a one-to-one session with a student advisor to talk over their worries and difficulties
Trammell	2019	US	Pepperdine University	N = 44 Male (n = 11), Female (n = 33) Mean age = 19.09, SD = 1.44	2 therapy dogs Treatment condition: Participants could pet, rest their hand on, or simply sit next to, their preferred dog as they wished	Control condition: Participants were taken to a similar room but with no dogs present.
Ward-Griffin et al.	2018	Canada	Canadian public university	N = 357 78% female Mean age = 19.4, SD = 3.7	7ཞ12 therapy dogs Treatment condition: Students can contact with dogs and handlers at each 90-min session.	Control condition: Students are not exposed to the therapy dog session.
Williams et al.	2018	US	Belmont University	N = 39 Females (N = 27), Males (N = 12) Mean age = 24.42, Range = 21–30	4 therapy dogs Treatment condition: 12 minutes of activities with therapy dogs including petting, brushing, holding, and/or talking to the dog.	Control condition: Control subjects were given the opportunity to engage in their normal pre-exam routine for 12 minutes. For some participants this meant independent studying.

Table 2

Summary table of papers (n = 13).
Paper	Year	Country	Setting/ Context	Sample characteristics	Intervention	Control/ Comparison Group
Anderson & Brown	2021	USA	Bachelor of Science in Nursing Program	N = 89 Male (n = 9), Female (n = 80) Age range = 20–22 Previous Anxiety Diagnosis = 33% of participants	4 dogs and their handlers Treatment condition: The participants completed an interaction with the therapy dogs for 35–45 minutes prior to the medication calculation exam.	Control condition: Participants interacted with each other for 35–45 minutes in a separate and secluded room without dogs present.
Barker et al.	2016	USA	Virginia Commonwealth University	N = 78 (completed one condition), N = 57 (completed both conditions) 76.9% female (n = 60 females, 18 males) Mean age = 19.38, SD = 1.75	10 therapy dogs Treatment condition: Students were permitted to freely interact with any of the dog teams during the 15-minute intervention.	Control condition: Attention-control - completing the Family Life-Space Diagram.
Barker et al.	2017	USA	University counseling center event	N = 74 Primarily white (56.8%) and 75.7% were females (75.7%) Mean age = 19.38, SD = 1.75	10 therapy dogs Treatment condition: Students in small groups interacted with any of the dog teams for 15 minutes	Control condition: Attention-control - completing the Family Life-Space Diagram.
Binfet	2017	Canada	Mid-size western Canadian university	N = 163 78% female Mean age = 18.85, SD = 2.65, Range = 17–49	14 therapy dogs Treatment condition: Interaction with a therapy dog for 20 minutes.	Control condition: Complete a business-as-usual model (i.e., a typical activity undertaken by participants) that had them study information from a course they were currently taking.
Binfet et al.	2021	Canada	Western Canadian University	N = 284 77% female, 21% male, 2% non-binary Mean age = 20.4, SD = 2.38, Range = 17–36	24 therapy dogs Treatment condition: Participants interacted with therapy dogs and were asked to engage in direct physical contact (e.g., caressing or petting the dog) for 20 minutes Treatment condition 2: Participants were in the immediate proximity of a therapy dog but engaged in no physical contact with the dog, we excluded this data from the meta-analysis	Control condition: Only the canine handler (no dogs) were present
Grajfoner et al.	2017	UK	Heriot–Watt University	N = 132 Mostly females (n = 85) Mean age = 21.6, SD = 3.4, Range = 17–34	6 therapy dogs Treatment condition: Participants interacted with both a handler and their dog for 20 mins.	Control condition: Participants interacted with a handler only (HO) Control condition 2: Participants interacted with a dog only (DO), we excluded this data for the meta-analysis
Haefelin et al.	2020	USA	Liberal arts and sciences college in western PA	N = 165 Male (n = 55), Female (n = 108), Other (n = 1), Preferred not to answer (n = 1) Mean age = 19.38, SD = 1.13, Age range = 18–22	1 dog and handler Treatment condition: Participants were asked to interact with the condition for 1 minute.	Control condition: Watch a video on a provided laptop computer that shows dogs being playful.
Kivlen et al.	2022	USA	A large Midwestern university	N = 104 79% female Mean age = 23.72, SD = 2.39	5 therapy dogs Treatment condition: Participants engaged in the CAI (Canine-Assisted Intervention) for 6 weeks in self-identified cohorts of 3 to 5 students, each session lasts for 35 minutes.	Control condition: Students were told that they were on the waitlist and given the option to engage in the intervention after data collection.
Manville et al.	2022	UK	Middlesex University	N = 60 Female (n = 47), Male (n = 13) Mean age = 25.3, SD = 6.99, Range = 19.1–52	1 therapy dog Treatment condition: Participants interact with dog for 10min. Petting and talking to the canine were the most common interactions.	Control condition: A neutral task of watching a PowerPoint presentation with unrelated (non-animal), neutral images for 10 minutes.
Spruin et al.	2020	UK	Local university	N = 94 Male (n = 37), Female (n = 57) Mean age = 22.76, SD = 4.87, Range = 18–46	1 therapy dog Treatment condition: Participants were free to engage with the therapy dog however they wanted for 30 minutes Treatment condition 2: Participants listened to a pre-recorded 30-minute guided mindfulness exercise, consisting of a mindful meditation of the breath, we excluded this data from the meta-analysis	Control condition: The standard treatment for student stress and anxiety at the target university, a one-to-one session with a student advisor to talk over their worries and difficulties
Trammell	2019	US	Pepperdine University	N = 44 Male (n = 11), Female (n = 33) Mean age = 19.09, SD = 1.44	2 therapy dogs Treatment condition: Participants could pet, rest their hand on, or simply sit next to, their preferred dog as they wished	Control condition: Participants were taken to a similar room but with no dogs present.
Ward-Griffin et al.	2018	Canada	Canadian public university	N = 357 78% female Mean age = 19.4, SD = 3.7	7ཞ12 therapy dogs Treatment condition: Students can contact with dogs and handlers at each 90-min session.	Control condition: Students are not exposed to the therapy dog session.
Williams et al.	2018	US	Belmont University	N = 39 Females (N = 27), Males (N = 12) Mean age = 24.42, Range = 21–30	4 therapy dogs Treatment condition: 12 minutes of activities with therapy dogs including petting, brushing, holding, and/or talking to the dog.	Control condition: Control subjects were given the opportunity to engage in their normal pre-exam routine for 12 minutes. For some participants this meant independent studying.

All studies were conducted in Western countries (e.g. Canada, USA, UK). All interventions included students interacting with both dogs and handlers concurrently, while the control design varied in each study.

Main Effect

Results from random-effects meta-analysis revealed a statistically significant overall effect size of d = -0.703 (95% CI [-0.923, -0.483], z = -6.27, p < 0.001), indicating an average strong effect. However, three specific studies [10, 42, 50] had no statistically significant effects. Among all studies, Trammell [52] demonstrated the strongest effect size of -1.342 (95% CI [-1.997, -0.687]), while Ward-Griffin et al. [50] reported the smallest effect size of -0.129 (95% CI [-0.379, 0.122]). Additionally, high heterogeneity was observed across the included studies (I² = 71.77, p < 0.001), suggesting substantial variability between intervention effects (Fig. 2).

Furthermore, the funnel plot (Fig. 3) raises concerns regarding potential publication bias, as 5 out of 13 studies are situated outside the 95% confidence interval. To investigate the possibility of small-study effects, an Egger test was performed (z = -1.96, p = 0.049). As an example of small-study effects, the largest effect size of -1.34 by Trammell [52] is originated from the second smallest sample size (N = 44) among the included studies, aligning with the statistically significant evidence of the small-study effects.

Trim and Fill Analysis

After conducting the trim-and-fill analysis, the results indicated no missing studies to be imputed, and the imputed effect size remained the same as the observed effect size (-0.703). This suggests that even after accounting for potential bias, the estimated effect of canine-assisted therapy on reducing stress and anxiety levels among university students remains consistent. The confidence interval for the imputed effect size also remained the same as the observed effect size, ranging from − 0.923 to -0.483. The adjusted funnel plot (Fig. 4) presents a more symmetrical distribution with 3 studies falling outside the 95% confidence interval, suggesting that the analysis successfully accounted for potential asymmetry caused by publication bias. Based on these results, it appears that the observed effect size remains robust even after accounting for potential publication bias, indicating that the estimated effect of canine-assisted therapy is stable and reliable.

However, as Sterne et al. [53] stated, the trim and fill analysis works based on the assumption that the funnel plot asymmetry is only influenced by publication bias, and the analysis performs poorly if high between-study heterogeneity is present. Even though the trim and fill analysis suggested that our overall effect size remains robust, we emphasize the need to interpret the results with great caution as there could be other unknown factors affecting the initial asymmetry of the funnel plot, and high heterogeneity was also found in the included studies.

Subgroup Analysis: Intervention Duration

To explore potential differences in intervention effectiveness based on the duration of the intervention, our analysis divided the interventions into three groups: 0–14 minutes (short duration), 15–29 minutes (medium duration), and 30 minutes or more (long duration). Previous findings suggest that canine-assisted therapy sessions of both 5 and 20 minutes hold significant potential to reduce individuals’ stress [43]. Nevertheless, to our knowledge, there is still no standardized duration for these intervention sessions. Categorizing the interventions by duration could help determine the necessary length for effectiveness and provide replicability for future research.

For Group 0 (0–14 minutes), the pooled effect size was − 0.883 (95% CI [-1.170, -0.596]) with no observed heterogeneity in this subgroup (I² = 0.00, p = 0.564). The result suggests a strong and consistent effect of short CAT sessions on reducing stress and anxiety across studies. This consistency is notable given that one of the interventions was as short as 1 minute [46], suggesting that even very brief interventions can effectively reduce stress and anxiety levels. However, it is essential to note the limitation due to the small number of studies (3 studies), which could limit the ability to detect heterogeneity. Therefore, further research might be necessary for a more robust conclusion.

In Group 1 (15–29 minutes), while there was still a reduction in stress and anxiety levels (effect size of -0.650 with a 95% CI [-1.004, -0.296]), the results varied significantly across studies (I² = 74.97, p = 0.002). Similarly, the variation was also present in Group 2 (30 minutes or more), where the effect size was − 0.567 (95% CI [-1.008, -0.125]) with further high heterogeneity (I² = 81.01, p = 0.002). These results indicate that while these longer sessions can be beneficial, their impact is not consistent. It might be influenced by other factors such as the context of the intervention, the individual's preferences and experiences with animals, or the specifics of the program's delivery.

We evaluated the differences in effect sizes between these groups using a chi-square test of group differences, yielding a non-significant result (Q_b = 1.79, p = 0.41). This indicates that there was no statistically significant difference in the effectiveness of the interventions across the three duration groups.

Overall, our subgroup analysis shows that while all durations of interventions are effective in reducing stress and anxiety, shorter interventions (0–14 minutes) appear to offer a consistently effective option, with no observed heterogeneity. Yet, two out of the three studies [48, 51] in the short-duration group have the smallest (N = 39) and third smallest (N = 60) sample sizes among all included studies. Given the evidence of small-study effects in our findings, caution is warranted when interpreting the effectiveness based on intervention duration. In contrast, the effectiveness of interventions lasting 15 minutes or more varies significantly between studies, reflecting greater variability in outcomes. These findings highlight the potential of brief interventions for stress and anxiety reduction, despite the need for more research to understand the variability and complexity associated with longer durations.

Risk of Bias

All 13 included studies were assessed using the Cochrane Risk-of-Bias tool [54]. Sixteen outcomes from all studies were evaluated to have some concerns, while 10 outcomes were identified as high-risk. Overall, no studies were assessed to be low-risk; 6 out of the 13 studies had some concerns, while the remaining were classified as high-risk. Similar to previous meta-analyses conducted on animal-assisted interventions, such as Huber et al. [23], we found that most studies could not implement blinding procedures since the presence of therapy canines during the intervention made it obvious to both researchers and possibly the participants that they were in the treatment condition. This, in turn, might have likely influenced the self-reported outcomes, thereby causing many studies to be rated as “some concerns” and high-risk. The overview of the risk of bias results can be referred to in Fig. 5, and specific details can be found in Supplementary Material C.

Subgroup Analysis: Risk of Bias

To address potential biases arising from variations in the risk of bias among studies included in our meta-analysis, we conducted a subgroup analysis comparing the effect sizes of studies categorized as “some concerns” and “high-risk”. The pooled effect size for studies with some concerns was − 0.935 (95% CI [-1.325, -0.544]), while for high-risk studies, it was − 0.593 (95% CI [-0.842, -0.345]). We further evaluated the differences in effect sizes between these groups using a chi-square test of group differences, yielding a non-significant result (Q_b = 2.09, p = 0.148). This indicates that there was no statistically significant difference in the effectiveness of the interventions between studies with some concerns and high-risk studies. In general, our findings suggest that while studies with some concerns showed a larger effect size on average compared to high-risk studies, this difference was not significant.

Overall, our meta-analysis demonstrates that canine-assisted therapy is effective in reducing students’ stress and anxiety levels, with an average strong effect size. However, the high heterogeneity value indicates that the effectiveness of canine-assisted therapy might not be consistent across all samples or settings. Given the presence of small-study effects and the study's small sample size with the largest effect size, it is important to interpret these findings cautiously.

While our meta-analysis suggests that canine-assisted therapy is indeed effective in reducing stress and anxiety levels among students, several factors may contribute to the heterogeneity in effect sizes across studies. Notably, variations in study design could highly influence the heterogeneity of our results. Based on the summary table of papers (Table 2), we found inconsistencies in the control group designs across studies. Control participants were engaged in various tasks, such as completing the Family Life-Space Diagram [10], being placed on a waitlist [47], and receiving counseling [49]. This variation in the control condition may have contributed to the pronounced heterogeneity observed. Nevertheless, it is also plausible that the high heterogeneity is attributable to the small number of selected studies in our meta-analysis. As a result, drawing definitive conclusions about the factors contributing to the observed variability requires a more thorough consideration.

From a theoretical standpoint, our findings align with social support theory, which posits that interactions with therapy dogs and handlers serve as a source of social support, fostering feelings of connectedness and reducing feelings of isolation among students [18]. CAT primarily provides emotional support, which is crucial for buffering against stress and anxiety. This unique form of social support provided by therapy dogs complements human support networks, as suggested by McNicholas and Collis [20]. The non-judgmental, unconditional support facilitates emotional relief, aiding individuals in reducing their stress and anxiety levels. However, since the effect size observed in our analysis is moderate and the heterogeneity value is high, CAT may need to be part of a broader, multifaceted approach to mental health support for university students. Universities and mental health professionals could consider integrating canine-assisted therapy with other interventions, such as counseling or stress management programs, to enhance overall effectiveness.

Limitations of Included Evidence

Similar to the previous AAI meta-analysis by Huber et al. [23], the limitation of the included studies is the predominance of female participants, with percentages ranging from 60–95%. This imbalance in participant demographics may limit the generalizability of the findings to male populations. The overrepresentation of female participants could be attributed to recruitment practices in fields such as psychology and nursing, which typically have higher proportions of female students. However, it is important to note that there are known differences in how males and females react to and experience stress and anxiety [55–56]. Future research should aim to address this limitation by including more comprehensive data and assessing potential gender differences in the impact of CAT on reducing stress and anxiety levels among university students.

Limitations of the Review Process

Another limitation is the high methodological heterogeneity observed among the included studies, which may have impacted the interpretation of results. We propose that this heterogeneity is partly attributable to the broad range of criteria for animal-assisted therapy (AAT), which is referred to as canine-assisted therapy (CAT) in this analysis. Currently, there is a lack of a standardized theoretical framework for evaluating the effectiveness of AAT (CAT), leading to variations in intervention protocols, treatment goals, and outcome measures across studies. For instance, the duration and frequency of interactions with therapy dogs varied considerably among the included studies, ranging from brief sessions lasting only a minute to longer interventions spanning several weeks. Additionally, differences were observed in the design of control conditions and outcome assessments, further contributing to methodological inconsistencies. Therefore, addressing these challenges in standardizing research and operational procedures for AAT (CAT) is crucial for enhancing the validity and reliability of findings in future studies.

Implications

The implications of these findings are substantial for university administrators considering the implementation of CAT on their campuses. Despite the methodological limitations identified, CAT emerges as a pragmatic solution for addressing the increasing mental health challenges faced by university students, especially in the aftermath of the COVID-19 pandemic. The low cost, easy scalability, and high popularity of CAT, coupled with its effectiveness in reducing stress and anxiety levels among students, make it a feasible option for universities seeking to promote student well-being. By leveraging the benefits of CAT, universities can play a significant role in fostering resilience and supporting the mental health needs of their students amidst evolving societal challenges.

In conclusion, this meta-analysis aims to evaluate the impact of Canine-Assisted Therapy (CAT), implemented in university settings on students' stress and anxiety levels. Generally, the findings from this review indicate a consistent trend wherein CAT effectively reduces stress and anxiety levels among university students. Based on the meta-analysis's main results, the quality of the included studies was moderate, with a high value of heterogeneity. Therefore, this paper emphasizes that further research may be needed to explore factors contributing to the observed heterogeneity and to identify specific student populations or contexts in which canine-assisted therapy may be most beneficial. Additionally, researchers should carefully consider their study designs, particularly regarding control conditions, to ensure an accurate assessment of the effects of canine-assisted therapy.

AAI

Animal-Assisted Interventions

AAA

Animal-Assisted Activities

AAE

Animal-Assisted Education

AAPT

Animal-Assisted Psychotherapy

AAT

Animal-Assisted Therapy

AVP

Animal Visitation Program

CAT

Canine-Assisted Therapy

RCT

Randomized Controlled Trial

Ethics Approval and Informed Consent

Not applicable to secondary data.

Consent for Publication

Not applicable.

Availability of Data and Materials

Not applicable.

Competing Interests

The authors declare that they have no competing interests.

Funding

The current study is not being funded.

Authors' contributions

SS analyzed and interpreted the data from the meta-analysis and subgroup analysis results. ZL was a major contributor to drafting the manuscript. Both SS and ZL contributed equally to study selection, screening, evaluating the levels of bias, and the overall design of the study. The second authors, ZW and SW, reviewed and edited the statistical results and manuscript. CN supervised the scientific quality of the entire meta-analytic process and revised the final manuscript.

Acknowledgment

Not applicable.

Bantjes J, Hunt X, Stein DJ. Anxious, Depressed, and Suicidal: Crisis Narratives in University Student Mental Health and the Need for a Balanced Approach to Student Wellness. Int J Environ Res Public Health. 2023;20(6):4859–9.
Fostering College Student Mental Health and Resilience [Internet]. American Psychiatric Association. 2023. https://www.psychiatry.org/news-room/apa-blogs/fostering-college-student-mental-health-and-resili.
Mofatteh M. Risk factors associated with stress, anxiety, and depression among university undergraduate students. AIMS Public Health. 2020;8(1):36–65.
Xun Ci Soh G, Hartanto A, Goh H, Majeed NM. Prevalence of Anxiety in College and University Students: An Umbrella Review. J Affect Disorders Rep. 2023;14:100658–8.
Ducharme J. Colleges Are Getting Creative to Support Mental Health [Internet]. TIME. 2023. https://time.com/6316217/college-mental-health-programs/.
Frazier P, Gabriel A, Merians A, Lust K. Understanding stress as an impediment to academic performance. J Am Coll Health. 2019;67(6):562–70.
Muckle J, Lasikiewicz N. An exploration of the benefits of animal-assisted activities in undergraduate students in Singapore. Asian J Soc Psychol. 2017;20(2):75–84.
Peel N, Nguyen K, Tannous C. The Impact of Campus-Based Therapy Dogs on the Mood and Affect of University Students. International Journal of Environmental Research and Public Health. 2023;20(6):4759. https://www.mdpi.com/1660-4601/20/6/4759.
Flannery ME, The Mental Health Crisis on College Campuses [Internet]. National Education Association. ; 2023. https://www.nea.org/nea-today/all-news-articles/mental-health-crisis-college-campuses.
Barker SB, Barker RT, McCain NL, Schubert CM. A Randomized Cross-over Exploratory Study of the Effect of Visiting Therapy Dogs on College Student Stress Before Final Exams. Anthrozoös. 2016;29(1):35–46.
McDowall S, Hazel SJ, Cobb M, Hamilton-Bruce A. Understanding the Role of Therapy Dogs in Human Health Promotion. International Journal of Environmental Research and Public Health. 2023;20(10):5801. https://www.mdpi.com/1660-4601/20/10/5801.
Marcus DA. The Science Behind Animal-Assisted Therapy. Curr Pain Headache Rep. 2013;17(4).
Carapezza K. Learning about the experiences of canine-assisted therapy handlers [Internet]. Counseling Today. 2021. https://ctarchive.counseling.org/2021/08/learning-about-the-experiences-of-canine-assisted-therapy-handlers/.
Machová K, Součková M, Procházková R, Vaníčková Z, Mezian K. Canine-Assisted Therapy Improves Well-Being in Nurses. International Journal of Environmental Research and Public Health. 2019;16(19):3670. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6801790/.
Sánchez-Valdeón L, Fernández-Martínez E, Loma-Ramos S, López-Alonso AI, Bayón Darkistade E, Ladera V. Canine-Assisted Therapy and Quality of Life in People With Alzheimer-Type Dementia: Pilot Study. Frontiers in Psychology. 2019;10. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6563674/.
Narvekar HN, Narvekar HN. Canine-assisted Therapy in Neurodevelopmental Disorders: A Scoping Review. Eur J Integr Med. 2022;50:102112.
Haggerty JM, Mueller MK. Animal-assisted Stress Reduction Programs in Higher Education. Innov High Educ. 2017;42(5–6):379–89.
Thoits PA. Stress, Coping, and Social Support Processes: Where Are We? What Next? J Health Soc Behav. 1995;35:53–79.
Kort-Butler LA. Social Support Theory. Encyclopedia Juvenile Delinquency Justice. 2017;1–4.
McNicholas J, Collis G. Animals as social supports: Insights for understanding animal-assisted therapy. Handbook on animal-assisted therapy: Theoretical foundations and guidelines for practice. 2006;2:49–71.
Panayiotou G, Karekla M. Perceived social support helps, but does not buffer the negative impact of anxiety disorders on quality of life and perceived stress. Soc Psychiatry Psychiatr Epidemiol. 2013;48:283–94.
Córdova P, Patricia Gasser Gordillo N, Mejía, La I. Alberto Grajeda Chacón, Alberto Sanjinés Unzueta. Academic stress as a predictor of mental health in university students. Cogent Education [Internet]. 2023;10(2). https://www.tandfonline.com/doi/full/10.1080/2331186X.2023.2232686.
Huber A, Klug SJ, Abraham A, Westenberg E, Schmidt V, Winkler AS. Animal-Assisted Interventions Improve Mental, But Not Cognitive or Physiological Health Outcomes of Higher Education Students: a Systematic Review and Meta-analysis. Int J Mental Health Addict. 2022.
Charry-Sánchez JD, Pradilla I, Talero-Gutiérrez C. Effectiveness of Animal-Assisted Therapy in the Pediatric Population. J Dev Behav Pediatr. 2018;39(7):1.
Zhang Y, Yan F, Li S, Wang Y, Ma Y. Effectiveness of animal-assisted therapy on pain in children: A systematic review and meta-analysis. Int J Nurs Sci. 2021;8(1):30–7.
Jones MG, Rice SM, Cotton SM. Incorporating animal-assisted therapy in mental health treatments for adolescents: A systematic review of canine assisted psychotherapy. Morote Rios R, editor. PLOS ONE [Internet]. 2019;14(1). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6336278/.
Virués-Ortega J, Pastor-Barriuso R, Castellote JM, Población A, de Pedro-Cuesta J. Effect of animal-assisted therapy on the psychological and functional status of elderly populations and patients with psychiatric disorders: a meta-analysis. Health Psychol Rev. 2012;6(2):197–221.
Feng Y, Lin Y, Zhang N, Jiang X, Zhang L. Effects of animal-assisted therapy on hospitalized children and teenagers: A systematic review and meta-analysis. J Pediatr Nurs. 2021;60:11–23.
Germain SM, Wilkie KD, Milbourne VMK, Theule J. Animal-assisted Psychotherapy and Trauma: A Meta-analysis. Anthrozoös. 2018;31(2):141–64.
Hediger K, Wagner J, Künzi P, Haefeli A, Theis F, Grob C, et al. Effectiveness of animal-assisted interventions for children and adults with post-traumatic stress disorder symptoms: a systematic review and meta-analysis. Eur J Psychotraumatology. 2021;12(1):1879713.
Nimer J, Lundahl B. Animal-Assisted Therapy: A Meta-Analysis. Anthrozoös. 2007;20(3):225–38.
Waite TC, Hamilton L, O’Brien W. A meta-analysis of Animal Assisted Interventions targeting pain, anxiety and distress in medical settings. Complement Ther Clin Pract. 2018;33:49–55.
Moher D, Shamseer L, Clarke M, Ghersi D, Liberati A, Petticrew M et al. Preferred Reporting Items for Systematic Review and meta-analysis Protocols (PRISMA-P) 2015 Statement. Systematic Reviews [Internet]. 2015;4(1):1–9. https://pubmed.ncbi.nlm.nih.gov/25554246/.
Barker SB, Dawson KS. The Effects of Animal-Assisted Therapy on Anxiety Ratings of Hospitalized Psychiatric Patients. Psychiatric Serv. 1998;49(6):797–801.
STANDARDS OF PRACTICE IN ANIMAL-ASSISTED INTERVENTIONS [Internet]. Therapy Animal Standards. 2017. https://therapyanimalstandards.org/.
Crossman MK, Kazdin AE. Animal Visitation Programs in Colleges and Universities. Handbook on Animal-Assisted Therapy. 2015;333–7.
Animal Assisted Intervention [Internet]. Animal Assisted Intervention International. 2017. https://aai-int.org/aai/animal-assisted-intervention/.
Bert F, Gualano MR, Camussi E, Pieve G, Voglino G, Siliquini R. Animal Assisted Intervention: A Systematic Review of Benefits and Risks. European Journal of Integrative Medicine [Internet]. 2016;8(5):695–706. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7185850/.
American Psychological Association. Anxiety. American Psychological Association [Internet]. 2022; https://www.apa.org/topics/anxiety.
World Health Organization. Stress. World Health Organization [Internet]. 2023; https://www.who.int//news-room/questions-and-answers/item/stress/.
Anderson D, Brown S. The Effect of Animal-Assisted Therapy on Nursing Student Anxiety: A Randomized Control Study. Nurse Educ Pract. 2021;52:103042.
Barker SB, Barker RT, McCain NL, Schubert CM. The Effect of a Canine-assisted Activity on College Student Perceptions of Family Supports and Current Stressors. Anthrozoös. 2017;30(4):595–606.
Binfet JT. The Effects of Group-Administered Canine Therapy on University Students’ Wellbeing: A Randomized Controlled Trial. Anthrozoös. 2017;30(3):397–414.
Binfet JT, Green FLL, Draper ZA. The Importance of Client–Canine Contact in Canine-Assisted Interventions: A Randomized Controlled Trial. Anthrozoös. 2021;1–22.
Grajfoner D, Harte E, Potter L, McGuigan N. The Effect of Dog-Assisted Intervention on Student Well-Being, Mood, and Anxiety. Int J Environ Res Public Health. 2017;14(5):483.
Haefelin N, Lange N, Sweigert B, Yonto M, Rivardo MG. Anxiety Reduction in College Students after Brief Interaction with a Therapy Dog or Animatronic Dog. North American Journal of Psychology [Internet]. 2020;22(3):411. link.gale.com/apps/doc/A637227331/HRCA?u = duke_beta&sid = googleScholar&xid = 097f13a4.
Kivlen C, Winston K, Mills D, DiZazzo-Miller R, Davenport R, Binfet JT. Canine-Assisted Intervention Effects on the Well-Being of Health Science Graduate Students: A Randomized Controlled Trial. Am J Occup Therapy. 2022;76(6).
Manville K, Coulson M, Reynolds G. Canine-Assisted Intervention Reduces Anxiety and Stress in Higher Education Students: A Randomized Controlled Trial. Soc Anim. 2022;1–22.
Spruin E, Dempster T, Islam S, Raybould I. The effects of a therapy dog vs mindfulness vs a student advisor on student anxiety and well-being. J Furth High Educ. 2020;45(5):1–13.
Ward-Griffin E, Klaiber P, Collins HK, Owens RL, Coren S, Chen FS. Petting away pre-exam stress: The effect of therapy dog sessions on student well-being. Stress Health. 2018;34(3):468–73.
Williams C, Emond K, Maynord K, Simpkins J, Stumbo A, Terhaar T. An Animal-Assisted Intervention’s Influence on Graduate Students’ Stress and Anxiety Prior to an Examination. OALib. 2018;05(09):1–16.
Trammell JP. Therapy Dogs Improve Student Affect but Not Memory. Anthrozoös. 2019;32(5):691–9.
Sterne J, Egger M, Moher D, Chapter. 10: Addressing reporting biases. Cochrane Handbook for Systematic Reviews of Interventions [Internet]. 5.2.0 ed. Boutron I, editor. Cochrane; 2017. .
Sterne JAC, Savović J, Page MJ, Elbers RG, Blencowe NS, Boutron I et al. RoB 2: a revised tool for assessing risk of bias in randomised trials. BMJ [Internet]. 2019;366(1):l4898. https://www.bmj.com/content/366/bmj.l4898.
Merz CJ, Wolf OT. Examination of cortisol and state anxiety at an academic setting with and without oral presentation. Stress. 2014;18(1):138–42.
Taylor MK, Larson GE, Hiller MD, Padilla GA, Wilson IM, Schmied EA, et al. Sex differences in cardiovascular and subjective stress reactions: prospective evidence in a realistic military setting. Int J Biology Stress. 2013;17(1):70–8.

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Canine-Assisted Therapy in Reducing Stress and Anxiety Levels of University Students: Systematic Review and Meta-analysis of Randomized Controlled Trials

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