Multi-site, Longitudinal Trial Evaluating the Efficacy, Mechanisms, and Moderators of Service Dogs for Military Veterans With PTSD

Posttraumatic stress disorder (PTSD) among military Veterans is a critical public health concern. Veteran suicide rates exceed those of the general population, with the disorder creating a mental health challenge that is costly and debilitating. The majority of Veterans with PTSD also have comorbid mental health diagnoses, such as generalized anxiety disorder, substance abuse disorder, and major depression. The treatment of Veteran PTSD and comorbid disorders represents an important therapeutic and rehabilitation problem. The disorder is complex and difficult to treat, with high treatment dropout and nonresponse rates spurring some Veterans to seek complementary integrative health strategies. One promising complementary strategy is the provision of a trained service dog. Initial evidence across multiple research groups highlights service dogs as a promising complement to evidence-based practices that can offer short-term improvements. However, the long-term effectiveness, mechanisms of action, and moderators of efficacy remain largely unknown. Thus, the overarching objective of this proposal is to understand how, why, and for whom PTSD service dogs are most effective.

To address this objective, the present project will assess the longitudinal efficacy and dose-response curve of service dogs for Veteran PTSD symptomology and psychosocial functioning. The research design will consist of a two-arm, randomized clinical trial (RCT) with longitudinal assessments over a period of 15 months. Results are expected to elucidate the clinical impact of service dogs for military Veterans with PTSD, as well as the biobehavioral mechanisms of action and characteristics that moderate efficacy. These outcomes will support the long-term goal of accelerating complementary and integrative health interventions, through optimized and evidence-based service dog interventions. As such, this project will further advance the scientific understanding of human-animal interactions for psychosocial health.

Study Overview

• Status: Active, not recruiting
• Conditions: Stress Disorders, Post-Traumatic; Combat Stress Disorders; Animal-Human Bonding
• Intervention / Treatment: Other: PTSD Service Dog

• Study Type: Interventional
• Enrollment (Estimated): 150
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Arizona
    • Tucson, Arizona, United States, 85719
      • University of Arizona

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Applied for and approved to receive a psychiatric service dog from Canine Companions, K9s For Warriors, or America's VetDogs
• First service dog (not a successor service dog)
• Military service
• Honorable discharge or current honorable service
• Diagnosis of PTSD
• No conviction of any crimes against animals
• Able to follow the approved study timeline for randomization

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Usual Care
Experimental: PTSD Service Dog	Other: PTSD Service Dog; According to the Americans with Disabilities Act (ADA), a service dog is a dog that is trained to perform specific tasks to mitigate a disability. For PTSD service dogs, examples include detecting and alerting to physical signs of distress to interrupt anxiety and panic attacks, waking up Veterans from nightmares, and retrieving medication. In addition to trained tasks, service dogs live with the Veterans to provide emotional value as a source of comfort and companionship. Under the ADA guidance, PTSD service dogs have pubic access and are legally allowed to accompany their person in public places such as grocery stores, workplaces, and schools. In the proposed study, service dogs will be sourced from three national service dog providers, including K9s For Warriors, Canine Companions, and America's VetDogs. All three providers have an established track record of training and providing service dogs for PTSD, as well as collaborating with the investigative team in research.; Other Names: PTSD Assistance Dog; Psychiatric Service Dog

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
PTSD Severity and symptoms via self-report	Posttraumatic Stress Disorder Checklist for DSM-V (PCL-5, Range 0-80, Lower scores indicate a better outcome)	8 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Depression	Patient Health Questionnaire (PHQ-9, Range 1-27, Lower scores indicate a better outcome)	8 months
Anxiety	Patient Reported Outcomes Measurement Information System (PROMIS) - Anxiety 8a (Raw Score Range 8-40, Lower scores indicate a better outcome)	8 months
PTSD Severity and symptoms via blinded clinician rating	Clinician-Administered PTSD Assessment for the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition DSM-V (CAPS-5-R, Range 0-200, Lower scores indicate a better outcome)	8 months

Collaborators and Investigators

• Sponsor: University of Arizona
• Collaborators: Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

Study record dates

Study Major Dates

• Study Start (Actual): September 15, 2023
• Primary Completion (Estimated): August 1, 2028
• Study Completion (Estimated): August 1, 2028

Study Registration Dates

• First Submitted: June 2, 2023
• First Submitted That Met QC Criteria: June 2, 2023
• First Posted (Actual): June 12, 2023

Study Record Updates

• Last Update Posted (Actual): February 18, 2026
• Last Update Submitted That Met QC Criteria: February 16, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Trauma and Stressor Related Disorders; Mental Disorders; Stress Disorders, Traumatic; Behavior; Human-Animal Interaction; Stress Disorders, Post-Traumatic; Combat Disorders; Human-Animal Bond
• Other Study ID Numbers: STUDY00002088; R01HD106413 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No