Over the last two decades, there has been a tremendous increase in the popularity and implementation of animal-assisted interventions (AAIs). AAIs are programmes in which animals are employed to help a person or a group of people in a predetermined way.

Animal-assisted approaches are found in countless venues, ranging from medical settings, residential care facilities, the workplace, private therapy practices, courts and correctional facilities, parks and barns, as well as in educational settings including university campuses. In fact, there has been an enormous surge in popularity of university-based AAIs worldwide, with nearly 1,000 post-secondary institutions in the US alone hosting some type of animal-assisted activity (AAA) in recent years.1 Although comprehensive data on the demand and prevalence of university-based AAIs remain elusive, anecdotal evidence suggests that campus-based AAIs have become a popular, widespread practice that is growing and here to stay.

How can we best describe the nature of a typical university-based AAA?

Conceptualised as preventive interventions to promote students’ general wellbeing, most AAAs are conducted within the context of animal visitation programmes (AVPs), which provide the general student population with an opportunity to engage in hands-on petting of animals – mostly dogs – for five 35-minute interactions in small group settings, during final exam week.4 While some of these programmes are ad hoc in nature, such as university staff bringing their personal pets to campus, others use formal approaches, ranging from providing interaction with specially trained therapy dog-handler teams to providing interaction with adoptable animals from local shelters, including dogs, cats and other species.

Building on the popularity of AVPs and promising results of research employing randomised control trials (RCTs), some campuses have scaled up their implementation beyond occasional short visitation programmes to establishing drop-in AAAs at counselling centres, student union buildings and even dedicated space for permanent ‘drop-in’ centres. Extending beyond typical brief, singleexposure activities, researchers have started designing AAAs, programmes providing regular weekly sessions of structured and semi-structured stress prevention-themed workshops. These feature a combination of humananimal interaction activities (such as guided meditation and relaxation activities, small group discussions with peers while in physical contact with registered emotional comfort dogs), along with exposure to psychoeducational content.

One might assume that the implementation of AAAs on college campuses is a consequence of the prevailing model guiding preventive intervention research – the preventive intervention research cycle.5 According to this perspective, prevention programmes are first developed with a comprehensive theoretical and empirical understanding of the target issue, then tested for efficacy under tightly controlled research conditions, thereafter examined in real-world settings for effectiveness in broader populations, and finally disseminated for public implementation. However, this is not the case for university-based AVPs, which have enjoyed widespread implementation prior to dissemination of causal research demonstrating their effects. The omission of this important step provides a unique and valuable opportunity for prevention researchers to examine effects of existing programmes in real-life settings, which is an approach prevalent in causal research described below.

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What are the effects of college-based AVPs? Can students ‘pet their stress away’?

We first share our results of three studies designed to examine the effects of an existing, universal, college-based AVP on students’ affective and physiological indices of stress. These studies were conducted over a five-semester period, coinciding with the real-life implementation of a well-established university-based, animal-assisted stress prevention programme, the Pet Your Stress Away (PYSA) programme, during which college students were provided with an opportunity to physically interact in supervised group settings with cats and dogs brought to campus by the local humane society. Since university administrators planned implementation according to procedures developed and implemented several semesters prior to the study team’s involvement, we collaborated with them to facilitate inclusion of an embedded causal research design, featuring an efficacy trial, while the programme took place.

For our first study, we employed an RCT to examine the effects of 10 minutes of participation in the PYSA programme on students’ emotions (feeling content: anxious, irritable and depressed).6 We chose to examine these outcomes because momentary emotion states are indicators of individual differences in appraisal and arousal, known to play a major role in overall health and wellbeing. Students were randomly assigned to one of three blinded conditions, including:

  • an experimental condition in which participants engaged in 10 minutes of supervised petting of shelter cats and dogs in small groups;
  • a control condition, showing participants a 10-minute slide presentation featuring the same programme animals;
  • and a waiting list condition, in which participants were asked to wait quietly for 10 minutes while refraining from social interaction and/or media stimulation. 

The control and waiting list conditions were designed to isolate the distinct contributions of the physical components of human-animal interaction, separate from contributions incurred by aspects of visual exposure to animals and peers or experiencing no intervention. Students twice completed a self-report 25-item scale, rating the extent to which they experienced positive and negative emotions immediately before and after their 10-minute condition.

Results showed that 10 minutes of hands-on interaction with dogs and/or cats significantly lowered self-reported feelings of anxiety and irritability compared with either watching a slide presentation of the same animal pictures, or sitting quietly in a room for 10 minutes without socialising. Additionally, 10 minutes of hands-on interaction significantly increased feelings of contentment compared with the alternative treatment groups. The results suggest college-based AVPs provide effective momentary stress relief as indicated by increases in positive mood and decreases in negative mood states.

Although the PYSA programme was implemented with a universal focus to serve the general student population, we felt it was important to examine whether programme effects were moderated by the presence of clinical levels of depression. We did so because it is to be expected that the student population which seeks out stress prevention programmes may include a subset of students already experiencing stress-related symptoms at clinical levels. In addition, we informally observed noteworthy individual differences in students’ affective responses before, during and after the intervention conducted during our first study. We hypothesised that some students may have been challenged by the experience of waiting with unknown peers for extended periods of time, or received fewer benefits from the intervention than their peers. In our next study, we thus aimed to unpack the relative impacts of the real-life programme conditions students commonly encounter during such large-scale AVPs, such as having to queue for extended periods of time, and/or socialising with known and unknown peers. We examined the moderating role of clinical levels of depression assessed the week before the intervention by comparing the effects of three common AVP conditions to which students were randomly assigned:

  • a hands-on condition in which participants could freely pet cats and dogs in small groups for 10 minutes
  • an observation condition in which participants observed students in the hands-on condition engage with animals in close proximity, without the ability to physically interact with the animals themselves, while waiting their turn for 10 minutes
  • a control condition in which participants viewed a slide show with still images of the same animals for 10 minutes.
  • using a checklist, students again reported their momentary emotional states before and after the 10-minute interventions.

We found that 10 minutes of hands-on human animal interaction with dogs and cats again most reduced students’ negative emotion states, including those experiencing clinical levels of depression.7 This finding suggests that depressed students do benefit from universally conducted AVPs and may not require targeted interventions. We also found that merely observing other students interact with animals offered some benefits to participants who were queuing, except for clinically depressed students, who experienced significantly higher levels of irritability, depression and anxiety compared with those without clinical depression. These findings suggest that it is important to consider the conditions leading up to programme participation, to prevent inadvertently increasing negative emotions in already depressed students.

Given that an individual’s momentary emotional states are linked to activation of the hypothalamic pituitary adrenal (HPA) axis, the body’s physiological stress response system associated with the development of psychopathology in response to chronic or extreme stress, we next explored effects of the PYSA intervention on students’ salivary cortisol levels, a marker of HPA axis activity.

To capture unique programme effects of what is considered the most popular feature of college-based AVPs – touching and petting animals – the study team compared students’ salivary cortisol levels in response to 10 minutes of physical exposure – petting of cats and dogs – to 10 minutes of observing other students interact with animals, 10 minutes of visual exposure – observing still images of the same programme animals – and 10 minutes of waiting for programme access without exposure to programme animals, peers or media. Increasing our understanding about the unique contributions of these key components informs whether ‘petting’ during AVPs is a necessary causal condition, or whether socialisation with peers or viewing animals may be sufficient.

Results showed that students assigned to 10 minutes of hands-on interaction with cats and dogs exhibited significantly lower salivary cortisol levels at post test, compared with alternative conditions.8 The results were obtained while also considering the participants’ cortisol levels upon waking on the day of the intervention as well as any signs of dysregulation of participants’ diurnal cortisol patterns. These results provide, in our opinion, the most robust case for the efficacy of brief, university-based animal visitation programmes to reduce university students’ physiological stress.

Do AAAs work better than traditional stress management approaches?

While promising, the prior results do not inform whether hands-on exposure to animals reduces academic failure. In fact, there are no prior studies which have examined effects of exposure to college-based AVPs in strengthening cognitive aspects central to academic success such as executive functioning (EF) and/or attitudes towards studying and learning. In addition, we don’t know whether AAAs provide benefits above and beyond those incurred through traditional stress management approaches to alleviate negative consequences of stress such as psychosocial education or counselling sessions.

In our next project, the PETPALS study, we set out to examine whether, under which conditions, and for whom, an extended four-week long university-based, animal-assisted programme provides an effective approach to promote executive functioning in populations (at-risk of) for academic failure. We randomly assigned undergraduate students to one of three four-week-long programmes featuring varying levels of exposure to human-animal interaction (HAI) and evidenced-based stress management content delivered by master’s-level health educators, resulting in three conditions:

  1. Evidence-based academic stress management content only (0 per cent HAI)
  2. Human-animal interaction (HAI) with therapy dogs only (100 per cent HAI)
  3. Equal combinations of academic stress management content and HAI (50 per cent HAI)

While exposure to HAI and evidence-based content and activities varied, participants in each condition separately attended a series of four, 60-minute, onceweekly workshops, focused on topics relevant to academic stress prevention, including academic stress management, motivation and goal settings, improving sleep and coping with test anxiety.

In addition to examining the main effects on students’ on students’ EF by condition, we examined the moderating role of students’ risk status, which was assessed by considering students’ history of academic failure, suicidal ideation, clinical diagnosis of mental health issue(s), and learning disability. Findings showed that at-risk students experienced the least-compromised EF at post test when assigned to the HAI-only condition, as evidenced by a significant interaction between treatment condition and risk status on global EF and both main aspects of EF, metacognition and behavioural regulation.9 The effects on EF and metacognition of at-risk students remained significant six weeks later.

Findings suggest that college-based AVPs should consider the level of risk in the population they aim to assist, as well as the outcome they are hoping to affect when designing programmes that incorporate AAAs. In this case, when targeting executive functioning in at-risk students, results illustrate that providing students with targeted programmes that emphasise exposure to HAI rather than providing evidence-based content on stress management, motivation and goal setting, will yield the greatest effects.

Although causal findings are important, it is also important to consider findings from programme evaluations as they provide important insights into the student experience during interventions that incorporate AAAs. Using a mixed methods approach, our team conducted a programme evaluation embedded in the PETPALS efficacy trial and examined student responsiveness (for example, enjoyment, usefulness, recommendation and behavioural change) quantitatively and qualitatively using self-reported survey data collected immediately following the programme and again six weeks later.

The results suggest that combining evidence-based content presentations with HAI was associated with higher levels of enjoyment, perceived usefulness, and likelihood of recommendation compared with presenting content or HAI alone.10 Although combining exposure to content with HAI did not result in differences in perceived behavioural change by condition, the results suggested that incorporating HAI with existing stress prevention programming could increase the efficacy of a traditional stress prevention programme through increased student engagement.

What are the implications of research for the implementation of university-based AAAs?

In sum, although pathways by which positive impacts occur are not yet fully understood, recent causal evidence is emerging to suggest that the simple process of petting an animal during college-based AVPs reduces stress by improving mood states and down-regulating production of cortisol. In addition, while positive effects are present for typical and at-risk students, depending on the outcome targeted and the characteristics of the intervention, targeted implementation for at-risk students may be warranted. That said, sceptics will rightfully argue that the relatively low numbers of RCTs limits our ability to make strong causal arguments about the effects of AAAs on students’ functioning. As such, implications of results should agreeably be interpreted conservatively, as the studies examining effects of AAAs vary not only in research design but also by species, outcome, population, length, intensity, format and setting.

Altogether, we do not know whether findings generalise beyond the relatively homogeneous samples of these studies to date. Most AAA studies featured students who predominantly identify as female, Caucasian, and either have a pet at home or enjoy pets in general. It is unclear whether college-based AAAs confer benefits to students of colour, students who attend two-year colleges, or those who do not like animals.

What logistical considerations are important for safe and effective implementation?

Regardless of the animals’ species, it is important to collaborate with a community partner to ensure that volunteers and/or staff handling the animals are capable of ensuring human and animal welfare throughout the AAA. It is important that animals and handlers undergo screening, training, and institutional support to act as the canine’s advocate throughout their volunteer experience.

Next, securing a suitable venue for the AAA is paramount. Animals must have ready access to relieve themselves as appropriate to the species (quick access to outdoor space), ample room to move around and settle themselves, and access to water and food as needed. It is also important that the space is large enough or structured in an appropriate way to prevent crowding of students and volunteers who are either participating in the programme or waiting for the programme to begin.

Regardless of the level of involvement planned for handlers and study personnel, the reality of campus-based AAAs is that the animal’s presence often disarms people to share feelings or information that may warrant intervention. It is thus vital that animal handlers and implementation personnel undergo at least introductory training on identifying and responding to students’ distress and the disclosure of traumatic and/or abusive experiences.

One risk that may be overlooked, is the risk of transmission of zoonotic diseases between animals and participants involved. In addition to working with trained and accredited animal handlers who can monitor the health of the animals, ensure up-to-date vaccinations, veterinary care, and animal hygiene, several strategies can be used to lessen the risk of transmission of diseases. This includes ensuring close access to hand-washing stations, disallowing use of raw meat treats, and, for temporary use, antibacterial hand sanitiser, which should be used by participants after touching animals.

Last, but not least, it is of utmost importance to protect the safety and wellbeing of human participants. While interacting with humans is often an enjoyable experience for the animals, it is possible that the novel nature of the AAA setting or the unpredictable interaction behaviour of participants may elicit stress behaviours in the animals involved, which can lead to bites, scratches and/or unpleasant, fearful experiences for human participants. It is thus important to monitor animal behaviour during the AAA, and implement procedures to remove an animal from the intervention setting if needed.

Related articles


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