Combining Animal-assisted Intervention and Placebo-induced Analgesia
Condition: Pain; Therapeutic Alliance; Placebo
Study type: Interventional

Summary: 
      An increased interest of animal-assisted interventions (AAI) can be observed within clinical
      practice, even though it is still not entirely clear how the presence of an animal
      contributes to the outcome of a treatment. One theory maintains that the mere presence of an
      animal influences the therapeutic alliance between therapist and client.

      However, results from a recent study suggest that a relationship between patient and
      health-provider alone is not sufficient to influence treatment outcomes, but that a
      therapeutic rationale is needed and that verbal instructions and suggestions are highly
      important in shaping participants' treatment expectations.

      To investigate this theory, this study will combine AAI with a placebo intervention, as
      placebo interventions offer the basic form of intervention working through relationship and
      expectancy.

      The effects of the presence of a dog will be assessed with a standardized experimental heat
      pain paradigm (TSA-II) in a randomized controlled trial in healthy participants (N=128).

      After a baseline measurements of heat pain threshold and tolerance, participants will be
      randomly assigned to one of the following four conditions: a) placebo intervention , no dog
      present, b) placebo intervention, dog present, c) no placebo intervention, no dog present and
      d) no placebo intervention, dog present.

      The dog will be introduced after randomization. Expectancy will be induced by telling
      participants that the contact to an animal increases the oxytocin level, which has an non
      inflammatory effect.

      The placebo intervention will be a deceptive cream which is said to helps against pain.

      Afterwards, posttreatment measurements will be conducted and participants fill in
      questionnaires about their perceptions of the experimenter.
    

Detailed description: 
      A growing body of literature suggests that animal-assisted interventions (AAI) have important
      clinical effects on humans, e.g. decreased physiological stress, reduction of depression and
      anxiety symptoms and reduction in pain perception and experience. Such evidence leads to an
      increased interest in using AAI in clinical practice. However, it is still not quite clear
      how AAI works or in other words what it is that makes AAI effective. Therefore, it is crucial
      to investigate how the inclusion of animals in clinical practice contributes to beneficial
      therapeutic outcomes.

      In this regard, it has been assumed that the presence of an animal enhances the development
      of the therapeutic alliance, which, in turn, has been shown to play a crucial role in the
      outcome of the treatment.

      However, results from a recent study suggest that a relationship between patient and
      health-provider alone is not sufficient to influence treatment outcomes, but that a
      therapeutic rationale is needed and that verbal instructions and suggestions are highly
      important in shaping participants' treatment expectations.

      As placebo effects are related to therapeutic rationale and relationship, the investigators
      would like to use an expectancy-induced placebo intervention to identify if animal-assisted
      intervention also works through these two components.

      Given that placebo analgesia works well through therapeutic rationale the investigators
      decided to employ an animal-integrated placebo intervention study with healthy participants
      (N=128) in a standardized experimental heat pain paradigm. Even though a growing body of
      evidence highlights the positive effects of animal-assisted interventions until this day
      little is known about the mechanisms. There exist various hypotheses trying to explain why
      AAI works, most focusing on the crucial role of the animal in the intervention. However, to
      the best of the investigator's knowledge there has been no study which examined if the
      effectiveness of animal-assisted interventions could simply be explained by the power of the
      therapeutic rational and the relationship. Therefore, it is still unknown if AAI is effective
      because of the animal or because of its influence on the therapeutic relationship and the
      given therapeutic rationale.

      It is important to understand how AAI works. Moreover, if AAI, like other interventions, is
      about expectation and relationship, this could have important implications for clinical
      practice and a better understanding of how AAI must be used to be effective.

      If AAI works through similar mechanisms as the placebo, then both interventions should have a
      similar impact on the outcome of the intervention (reduced pain perception, increased placebo
      analgesia). Findings of this study could have important implications, not only for clinical
      practice of AAI but also for intervention in general as the results could help to better
      understand the importance of these two components.
    

Intervention name(s): Animal-assisted placebo condition; Placebo condition; Dog only condition; Control Condition
Intervention type(s): Other; Other; Other; Other
Intervention description(s): Participants receive the same verbal information as in the Placebo condition. Additionally, participants will receive the same verbal information as in the Dog only condition.; Participants receive verbal information that they are receiving an analgesic cream (i.e. ""Antidolor, containing Lidocain"), which has been shown to produce significant pain reduction in previous clinical trials. However, they will receive an inert cream.; Participants will get a therapeutic rationale for the presence of the dog. The rationale is supported in the literature and therefore not invented for the purpose of this study. Participants will be told that: "Studies have shown the presence of an animal can affect pain perception because the presence and the interaction with an animal can increase our Oxytocin level. Therefore, the investigators want to examine if the presence of a dog has an impact on your pain perception. While participants have to wait for the action time of the cream they are allowed to pet the dog. The intensity of interaction will be documented and be rated on a scale from 1-5 (1=very low degree of interaction, 5=very high degree of interaction). During the experiment the dog will be lying in the room with some distance to participants to avoid further physical interaction. The dog will always be lying at the same spot. Participants will still be able to see the dog.; Participants in this condition will receive no intervention. All instructions will be conveyed in a standardized manner to ensure that the participant-experimenter relationship is comparable in terms of friendliness and attention across all four conditions.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: randomized controlled parallel group within-subjects design
Masking: Single (Participant)
Primary purpose: Basic Science
Keywords: Treatment Rationale; animal-assisted intervention