A Pilot Observational Study in Ohio, USA of the Healing of Our Veterans Equine Services Intensive Intervention for Veterans with Trauma Histories.
Abstract: : Equine-assisted services are being increasingly utilized as complementary interventions for military veterans who have experienced trauma. However, rigorous research is lacking, and randomized controlled trials are needed. The H.O.O.V.E.S. Intensive intervention was developed for this population. This intensive program is an equine-assisted learning approach developed for veteran and active-duty military trauma survivors. The program integrates equine-assisted learning, peer mentorship and experiential learning in a residential retreat format. The primary aim of this pilot study was to determine if more rigorous studies of this intervention are warranted. Secondary aims were to assess preliminary outcomes and explore possible relationships between changes in outcome measures. : This was a pilot prospective study. Inclusion criteria for the program included veteran or active-duty military status and a history of trauma exposure. Data were collected from April-October of 2024 in Ohio, USA. Six psychological instruments were administered to participants before, immediately after and 90 days and 120 days after the intervention. These were the PTSD Checklist for DSM-5 (PCL-5), the Acceptance and Action Questionnaire II (AAQII), the Positive and Negative Affect Scale (PANAS), the State-Trait Anxiety Inventory (STAI), the Beck Depression Inventory (BDI) and the Posttraumatic Growth Inventory (PTGI). Analyses were conducted to assess for significant changes across the study timeframe and for relationships among the changes in psychological instrument scores. : Study participants were 32 veterans with trauma histories ranging in age from 30 to 67 years old. There were statistically significant pre- to post-intervention improvements for all instruments except the PTGI, suggesting short-term increased psychological flexibility (AAQII) and positive affect (PANAS-positive) as well as decreased anxiety (STAI), negative affect (PANAS-negative), depression (BDI) and PTSD symptoms (PCL-5). Changes in BDI and PCL-5 scores persisted at 120 days post-intervention whereas changes in the AAQII, PANAS and STAI did not persist. Increased psychological flexibility was correlated with reductions in negative affect, PTSD symptoms and anxiety, as well as with increases in positive affect. : Preliminary results reported herein suggest participation is associated with psychological benefits. Further, decreased experiential avoidance/increased psychological flexibility should be explored as an underlying mechanism potentially contributing to the benefits of participation in EAS. A randomized controlled trial of the H.O.O.V.E.S. Intensive program is warranted.
Publication Date: 2025-11-28 PubMed ID: 41373328PubMed Central: PMC12692443DOI: 10.3390/healthcare13233111Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
Overview
- This study investigated the effects of the Healing of Our Veterans Equine Services (H.O.O.V.E.S.) Intensive intervention, an equine-assisted learning program designed for veterans and active-duty military personnel with trauma histories.
- The research aimed to determine if further rigorous studies are justified by evaluating psychological outcomes before and after participation in the program.
Background and Purpose
- Equine-assisted services (EAS) are increasingly used as complementary therapies for veterans who have experienced trauma, but there is a lack of rigorous evidence supporting their effectiveness.
- The H.O.O.V.E.S. Intensive intervention combines equine-assisted learning, peer mentorship, and experiential learning delivered in a residential retreat format tailored for military trauma survivors.
- The primary purpose was to pilot the intervention and assess preliminary psychological outcomes, with the goal of determining if more robust randomized controlled trials (RCTs) are needed.
Study Design and Methods
- A pilot prospective observational study conducted in Ohio, USA from April to October 2024.
- Participants consisted of 32 veterans, aged 30 to 67, all with a history of trauma exposure.
- Eligibility required current or past military service and trauma history.
- Assessment instruments administered at four time points: before intervention, immediately after, and at 90 and 120 days post-intervention included:
- PTSD Checklist for DSM-5 (PCL-5) – measures PTSD symptoms
- Acceptance and Action Questionnaire II (AAQII) – measures psychological flexibility
- Positive and Negative Affect Scale (PANAS) – measures positive and negative emotions
- State-Trait Anxiety Inventory (STAI) – measures anxiety
- Beck Depression Inventory (BDI) – measures depression severity
- Posttraumatic Growth Inventory (PTGI) – measures positive psychological change after trauma
- Data analyses focused on identifying statistically significant changes over time and exploring correlations among changes in psychological measures.
Key Findings
- Significant improvements were observed from pre- to post-intervention on all measures except PTGI, indicating:
- Increased psychological flexibility as measured by AAQII.
- Increased positive affect (PANAS-positive).
- Decreased anxiety (STAI).
- Decreased negative affect (PANAS-negative).
- Decreased depression (BDI).
- Reduced PTSD symptoms (PCL-5).
- Improvements in depression and PTSD symptoms were sustained at 120 days post-intervention.
- Improvements in psychological flexibility, affect, and anxiety did not persist at 120 days.
- Correlations revealed that increased psychological flexibility related closely to:
- Decreases in negative affect, PTSD symptoms, and anxiety.
- Increases in positive affect.
Interpretations and Implications
- The findings suggest participation in the H.O.O.V.E.S. Intensive equine-assisted program is associated with meaningful psychological benefits in veterans with trauma histories.
- The sustained reductions in depression and PTSD symptoms are particularly promising for longer-term mental health improvements.
- The role of psychological flexibility (reduced experiential avoidance) appears to be a key underlying mechanism mediating benefits from the intervention.
- The lack of significant improvement in posttraumatic growth may indicate either a need for longer follow-up or specific program enhancements to foster this outcome.
- The pilot results support conducting larger, randomized controlled trials to rigorously evaluate efficacy and better understand mechanisms of the H.O.O.V.E.S. Intensive intervention.
Summary
- This pilot observational study provides preliminary evidence that the H.O.O.V.E.S. Intensive equine-assisted learning program offers psychological improvements in veterans with trauma histories.
- Improvements in symptoms of PTSD and depression were observed and maintained up to four months after the program.
- Psychological flexibility emerged as a potentially important factor in achieving these benefits.
- Future randomized controlled trials are necessary to confirm these findings and optimize this therapeutic approach for trauma-affected veterans.
Cite This Article
APA
Held A, Hubbard K, Nazarenko E, Marchand W.
(2025).
A Pilot Observational Study in Ohio, USA of the Healing of Our Veterans Equine Services Intensive Intervention for Veterans with Trauma Histories.
Healthcare (Basel), 13(23), 3111.
https://doi.org/10.3390/healthcare13233111 Publication
Researcher Affiliations
- H.O.O.V.E.S. (Healing of Our Veterans Equine Services), 4055 Wilkins Rd., Swanton, OH 43558, USA.
- H.O.O.V.E.S. (Healing of Our Veterans Equine Services), 4055 Wilkins Rd., Swanton, OH 43558, USA.
- Whole Health Service, VA Salt Lake City Health Care System, 500 Foothill Drive, Salt Lake City, UT 84148, USA.
- Whole Health Service, VA Salt Lake City Health Care System, 500 Foothill Drive, Salt Lake City, UT 84148, USA.
- Department of Psychiatry, University of Utah, 501 Chipeta Way, Salt Lake City, UT 84108, USA.
- Department of Animal, Dairy and Veterinary Sciences, Utah State University, 4815 Old Main Hill, Logan, UT 84322, USA.
Conflict of Interest Statement
The authors declare no conflicts of interest.
References
This article includes 65 references
- Hoge CW, Castro CA, Messer SC, McGurk D, Cotting DI, Koffman RL. Combat duty in Iraq and Afghanistan, mental health problems, and barriers to care.. N. Engl. J. Med. 2004;351:13–22.
- Suris A, Lind L. Military sexual trauma: A review of prevalence and associated health consequences in veterans.. Trauma Violence Abus. 2008;9:250–269.
- Kimerling R, Street AE, Pavao J, Smith MW, Cronkite RC, Holmes TH, Frayne SM. Military-related sexual trauma among Veterans Health Administration patients returning from Afghanistan and Iraq.. Am. J. Public Health. 2010;100:1409–1412.
- Gould CE, Rideaux T, Spira AP, Beaudreau SA. Depression and anxiety symptoms in male veterans and non-veterans: The Health and Retirement Study.. Int. J. Geriatr. Psychiatry. 2015;30:623–630.
- . Diagnostic and Statistical Manual of Mental Disorders, Text Revision.. .
- Rauch SA, Eftekhari A, Ruzek JI. Review of exposure therapy: A gold standard for PTSD treatment.. J. Rehabil. Res. Dev. 2012;49:679–687.
- Schottenbauer MA, Glass CR, Arnkoff DB, Tendick V, Gray SH. Nonresponse and dropout rates in outcome studies on PTSD: Review and methodological considerations.. Psychiatry. 2008;71:134–168.
- Bradley R, Greene J, Russ E, Dutra L, Westen D. A multidimensional meta-analysis of psychotherapy for PTSD.. Am. J. Psychiatry. 2005;162:214–227.
- Hoskins M, Pearce J, Bethell A, Dankova L, Barbui C, Tol WA, van Ommeren M, de Jong J, Seedat S, Chen H. Pharmacotherapy for post-traumatic stress disorder: Systematic review and meta-analysis.. Br. J. Psychiatry. 2015;206:93–100.
- Steenkamp MM, Litz BT, Hoge CW, Marmar CR. Psychotherapy for Military-Related PTSD: A Review of Randomized Clinical Trials.. JAMA. 2015;314:489–500.
- Imel ZE, Laska K, Jakupcak M, Simpson TL. Meta-analysis of dropout in treatments for posttraumatic stress disorder.. J. Consult. Clin. Psychol. 2013;81:394–404.
- Najavits LM. The problem of dropout from “gold standard” PTSD therapies.. F1000Prime Rep. 2015;7:43.
- Wood W, Alm K, Benjamin J, Thomas L, Anderson D, Pohl L, Kane M. Optimal Terminology for Services in the United States That Incorporate Horses to Benefit People: A Consensus Document.. J. Altern. Complement. Med. 2021;27:88–95.
- Earles JL, Vernon LL, Yetz JP. Equine-assisted therapy for anxiety and posttraumatic stress symptoms.. J. Trauma. Stress. 2015;28:149–152.
- Romaniuk M, Evans J, Kidd C. Evaluation of an equine-assisted therapy program for veterans who identify as ‘wounded, injured or ill’ and their partners.. PLoS ONE. 2018;13:e0203943.
- Ferruolo D.M. Psychosocial Equine Program for Veterans. Soc. Work. 2016;61:53–60. doi: 10.1093/sw/swv054.
- Steele E., Wood D.S., Usadi E.J., Applegarth D.M. TRR’s Warrior Camp: An Intensive Treatment Program for Combat Trauma in Active Military and Veterans of All Eras. Mil. Med. 2018;183((Suppl. 1)):403–407. doi: 10.1093/milmed/usx153.
- Shelef A., Brafman D., Rosing T., Weizman A., Stryjer R., Barak Y. Equine Assisted Therapy for Patients with Post Traumatic Stress Disorder: A Case Series Study. Mil. Med. 2019;184:394–399. doi: 10.1093/milmed/usz036.
- Burton L.E., Qeadan F., Burge M.R. Efficacy of equine-assisted psychotherapy in veterans with posttraumatic stress disorder. J. Integr. Med. 2019;17:14–19. doi: 10.1016/j.joim.2018.11.001.
- Marchand W.R. Potential Mechanisms of Action and Outcomes of Equine-Assisted Services for Veterans with a History of Trauma: A Narrative Review of the Literature. Int. J. Environ. Res. Public Health. 2023;20:6377. doi: 10.3390/ijerph20146377.
- Arnon S., Fisher P.W., Pickover A., Lowell A., Turner J.B., Hilburn A., Jacob-McVey J., Malajian B.E., Farber D.G., Hamilton J.F., et al. Equine-Assisted Therapy for Veterans with PTSD: Manual Development and Preliminary Findings. Mil. Med. 2020;185:e557–e564. doi: 10.1093/milmed/usz444.
- Fisher P.W., Lazarov A., Lowell A., Arnon S., Turner J.B., Bergman M., Ryba M., Such S., Marohasy C., Zhu X., et al. Equine-Assisted Therapy for Posttraumatic Stress Disorder Among Military Veterans: An Open Trial. J. Clin. Psychiatry. 2021;82:21m14005. doi: 10.4088/JCP.21m14005.
- Gehrke E.K., Noquez A.E., Ranke P.L., Myers M.P. Measuring the psychophysiological changes in combat Veterans participating in an equine therapy program. J. Mil. Veteran Fam. Health. 2018;4:60–69. doi: 10.3138/jmvfh.2017-0015.
- Gehrke E.K., Tontz P., Bhawal R., Schiltz P., Mendez S., Myers M.P. A Mixed-Method Analysis of an Equine Complementary Therapy Program to Heal Combat Veterans. J. Complement. Altern. Healthc. 2018;8:555739. doi: 10.19080/JCMAH.2018.08.555739.
- Hoopes K.H., Osborne M., Marchand W.R., Joubert K., Nazarenko E., Black H., Klinger W., Sheppard S. A pilot observational study of recreational trail riding for Veterans with addictive disorders. Complement. Ther. Med. 2022;65:102813. doi: 10.1016/j.ctim.2022.102813.
- Lanning B.A., Wilson A.L., Woelk R., Beaujean A.A. Therapeutic horseback riding as a complementary intervention for military service members with PTSD. Hum. Anim. Interact. Bull. 2018;6:58–82. doi: 10.1079/hai.2018.0013.
- Marchand W.R., Joubert K., Smith J., Nazarenko E., Klinger W., Sheppard S., Hoopes K.H. A Pilot Observational Study of Implementing an Equine-Assisted Services Program Within a VA Medical Center Residential Substance Use Disorder Treatment Program. Mil. Med. 2022;188:e2175–e2180. doi: 10.1093/milmed/usac028.
- Marchand W.R., Smith J., Hoopes K.H., Osborne M., Andersen S.J., Bell K., Nazarenko E., Macneill R., Joubert K. A pilot observational study of horsemanship skills training for Veterans with posttraumatic stress disorder. Complement. Ther. Med. 2022;72:102910. doi: 10.1016/j.ctim.2022.102910.
- Marchand W.R., Lackner R., Hartquist A., Finnell L., Nazarenko E. Evaluation of a mindfulness and self-compassion-based psychotherapy incorporating horses for Veterans who have experienced trauma. Complement. Ther. Med. 2023;72:102914. doi: 10.1016/j.ctim.2023.102914.
- Monroe M., Whitworth J.D., Wharton T., Turner J. Effects of an Equine-Assisted Therapy Program for Military Veterans with Self-Reported PTSD. Soc. Anim. 2019;29:577–590. doi: 10.1163/15685306-12341572.
- Zhu X., Suarez-Jimenez B., Zilcha-Mano S., Lazarov A., Arnon S., Lowell A.L., Bergman M., Ryba M., Hamilton A.J., Hamilton J.F., et al. Neural changes following equine-assisted therapy for posttraumatic stress disorder: A longitudinal multimodal imaging study. Hum. Brain Mapp. 2021;42:1930–1939. doi: 10.1002/hbm.25360.
- McCullough L., Risley-Curtiss C., Rorke J. Equine facilitated psychotherapy: A pilot study of effect on posttraumatic stress symptoms in maltreated youth. J. Infant Child Adolesc. Psychother. 2015;14:158–173. doi: 10.1080/15289168.2015.1021658.
- Duncan C.R., Critchley S., Marland J. Can praxis: A model of equine assisted learning (EAL) for PTSD. Can. Mil. J. 2014;14:64–69.
- Johnson R.A., Albright D.L., Marzolf J.R., Bibbo J.L., Yaglom H.D., Crowder S.M., Carlisle G.K., Willard A., Russell C.L., Grindler K., et al. Effects of therapeutic horseback riding on post-traumatic stress disorder in military veterans. Mil. Med. Res. 2018;5:3. doi: 10.1186/s40779-018-0149-6.
- Lanning B.A., Wilson A., Krenek N., Beaujean A.A. Using therapeutic riding as an intervention for combat veterans: An international classification of functioning, disability, and health (ICF) approach. Occup. Ther. Ment. Health. 2017;33:259–278. doi: 10.1080/0164212X.2017.1283282.
- Malinowski K., Yee C., Tevlin J.M., Birks E.K., Durando M.M., Pournajafi-Nazarloo H., Cavaiola A.A., McKeever K.H. The Effects of Equine Assisted Therapy on Plasma Cortisol and Oxytocin Concentrations and Heart Rate Variability in Horses and Measures of Symptoms of Post-Traumatic Stress Disorder in Veterans. J. Equine Vet. Sci. 2018;64:17–26. doi: 10.1016/j.jevs.2018.01.011.
- Wharton T., Whitworth J., Macauley E., Malone M. Pilot testing a manualized equine-facilitated cognitive processing therapy (EF-CPT) intervention for PTSD in veterans. Psychiatr. Rehabil. J. 2019;42:268–276. doi: 10.1037/prj0000359.
- Marchand W.R., Sullivan-Sakaeda L. A pilot observational study of a psychotherapy incorporating equines resiliency intervention for staff at a large medical center. Complement. Ther. Clin. Pract. 2022;49:101660. doi: 10.1016/j.ctcp.2022.101660.
- Marchand W.R., Sullivan-Sakaeda L., Lackner R., Taplin D., Nazarenko E. A replication study of a psychotherapy incorporating horses resiliency intervention for healthcare workers. Complement. Ther. Med. 2023;76:102965. doi: 10.1016/j.ctim.2023.102965.
- Kashdan T.B., Disabato D.J., Goodman F.R., Doorley J.D., McKnight P.E. Understanding psychological flexibility: A multimethod exploration of pursuing valued goals despite the presence of distress. Psychol. Assess. 2020;32:829–850. doi: 10.1037/pas0000834.
- Kashdan T.B., Barrios V., Forsyth J.P., Steger M.F. Experiential avoidance as a generalized psychological vulnerability: Comparisons with coping and emotion regulation strategies. Behav. Res. Ther. 2006;44:1301–1320. doi: 10.1016/j.brat.2005.10.003.
- Kashdan T.B., Rottenberg J. Psychological flexibility as a fundamental aspect of health. Clin. Psychol. Rev. 2010;30:865–878. doi: 10.1016/j.cpr.2010.03.001.
- Meyer E.C., Kotte A., Kimbrel N.A., DeBeer B.B., Elliott T.R., Gulliver S.B., Morissette S.B. Predictors of lower-than-expected posttraumatic symptom severity in war veterans: The influence of personality, self-reported trait resilience, and psychological flexibility. Behav. Res. Ther. 2019;113:1–8. doi: 10.1016/j.brat.2018.12.005.
- Jeffords J.R., Bayly B.L., Bumpus M.F., Hill L.G. Investigating the Relationship between University Students’ Psychological Flexibility and College Self-Efficacy. J. Coll. Stud. Ret. 2020;22:351–372. doi: 10.1177/1521025117751071.
- Chawla N., Ostafin B. Experiential avoidance as a functional dimensional approach to psychopathology: An empirical review. J. Clin. Psychol. 2007;63:871–890. doi: 10.1002/jclp.20400.
- Marx B.P., Sloan D.M. Peritraumatic dissociation and experiential avoidance as predictors of posttraumatic stress symptomatology. Behav. Res. Ther. 2005;43:569–583. doi: 10.1016/j.brat.2004.04.004.
- Weathers F.W., Litz B.T., Keane T.M., Palmieri P.A., Marx B.P., Schnurr P.P. The PTSD Checklist for DSM-5 (PCL-5) [(accessed on 19 July 2025)]; Available online: www.ptsd.va.gov.
- Blevins C.A., Weathers F.W., Davis M.T., Witte T.K., Domino J.L. The Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5): Development and Initial Psychometric Evaluation. J. Trauma. Stress. 2015;28:489–498. doi: 10.1002/jts.22059.
- Bond F.W., Hayes S.C., Baer R.A., Carpenter K.M., Guenole N., Orcutt H.K., Waltz T., Zettle R.D. Preliminary psychometric properties of the Acceptance and Action Questionnaire-II: A revised measure of psychological inflexibility and experiential avoidance. Behav. Ther. 2011;42:676–688. doi: 10.1016/j.beth.2011.03.007.
- Watson D., Clark L.A., Tellegen A. Development and validation of brief measures of positive and negative affect: The PANAS scales. J. Pers. Soc. Psychol. 1988;54:1063–1070. doi: 10.1037/0022-3514.54.6.1063.
- Marteau T.M., Bekker H. The development of a six-item short-form of the state scale of the Spielberger State-Trait Anxiety Inventory (STAI) Br. J. Clin. Psychol. 1992;31:301–306. doi: 10.1111/j.2044-8260.1992.tb00997.x.
- Spielberger C.D., Gorsuch R.L., Lushene R.E. Manual for the State-Trait Anxiety Inventory. Mind Garden; Palo Alto, CA, USA: 1983.
- Beck A.T., Steer R.A., Brown G.K. Manual for the Beck Depression Inventory-II. Psychological Corporation; San Antonio, TX, USA: 1996.
- Tedeschi R.G., Calhoun L.G. The posttraumatic growth inventory: Measuring the positive legacy of trauma. J. Trauma. Stress. 1996;9:455–471. doi: 10.1002/jts.2490090305.
- Harris P.A., Taylor R., Thielke R., Payne J., Gonzalez N., Conde J.G. Research electronic data capture (REDCap)—A metadata-driven methodology and workflow process for providing translational research informatics support. J. Biomed. Inform. 2009;42:377–381. doi: 10.1016/j.jbi.2008.08.010.
- Alfonso S.V., Alfonso L.A., Llabre M.M., Fernandez M.I. Project Stride: An Equine-Assisted Intervention to Reduce Symptoms of Social Anxiety in Young Women. Explore. 2015;11:461–467. doi: 10.1016/j.explore.2015.08.003.
- Frederick K.E., Ivey Hatz J., Lanning B. Not Just Horsing Around: The Impact of Equine-Assisted Learning on Levels of Hope and Depression in At-Risk Adolescents. Community Ment. Health J. 2015;51:809–817. doi: 10.1007/s10597-015-9836-x.
- Rytwinski N.K., Scur M.D., Feeny N.C., Youngstrom E.A. The co-occurrence of major depressive disorder among individuals with posttraumatic stress disorder: A meta-analysis. J. Trauma. Stress. 2013;26:299–309. doi: 10.1002/jts.21814.
- Silberstein L., Tirch D., Leahy R. Mindfulness, Psychological Flexibility and Emotional Schemas. Int. J. Cogn. Ther. 2012;5:406–419. doi: 10.1521/ijct.2012.5.4.406.
- He M., Li Y., Ju R., Liu S., Hofmann S.G., Liu X. The role of experiential avoidance in the early stages of an online mindfulness-based intervention: Two mediation studies. Psychother. Res. 2024;34:736–747. doi: 10.1080/10503307.2023.2232528.
- Beetz A., Schöfmann-Crawford I. Clinical Objectives for Animal-Assisted Interventions: Physiological and Psychological Targets in Trauma-Informed Practice. In: Jenkins P.T.M.A., editor. Transforming Trauma: Resilience and Healing Through Our Connections with Animals. Purdue University Press; West Lafayette, IN, USA: 2019.
- Fry N.E. Horses in the Treatment of Trauma. In: Jenkins P.T.M.A., editor. Transforming Trauma: Resilience and Healing Through Our Connections with Animals. Purdue University Press; West Lafayette, IN, USA: 2019.
- Marchand W.R., Klinger W., Block K., VerMerris S., Herrmann T.S., Johnson C., Shubin E., Sheppard S. Safety and psychological impact of sailing adventure therapy among Veterans with substance use disorders. Complement. Ther. Med. 2018;40:42–47. doi: 10.1016/j.ctim.2018.07.013.
- Marchand W.R., Klinger W., Block K., VerMerris S., Nazarenko E., Curtis H., Newton J., Herrmann T.S., Yabko B., Lane J. Mindfulness-based Therapeutic Sailing for Veterans with Psychiatric and Substance Use Disorders. Mil. Med. 2021;187:e445–e452. doi: 10.1093/milmed/usab030.
- Wilson E.O. Biophilia. Harvard University Press; Cambridge, MA, USA: 1984.
Citations
This article has been cited 0 times.Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists