Equine-assisted interventions for veterans with service-related health conditions: a systematic mapping review

BACKGROUND: Evidence-based treatments for service-related health conditions such as posttraumatic stress disorder (PTSD), depression, and traumatic brain injury (TBI) are not effective for all veterans. Equine-assisted interventions are emerging as an additional treatment modality, but little is known regarding the safe and effective delivery of these interventions. This study aimed to describe the following features of the body of literature concerning equine-assisted interventions among veterans: 1) veterans who have participated in equine-assisted interventions; 2) specific characteristics of equine-assisted interventions in veterans; and 3) the specific characteristics of research on equine-assisted interventions in veterans. METHODS: We conducted a systematic mapping review of peer-reviewed literature reporting on equine-assisted interventions among veterans between 1980 and 2017. Searches of nine databases yielded 3336 unique records, six of which met the inclusion criteria and were reviewed. Data relevant to the study aims were extracted and analyzed. RESULTS: Equine-assisted interventions among veterans disproportionately targeted psychosocial outcomes and yielded promising results. The detailed methods of EAI varied in the reported studies, ranging from communicating with the horse to mounted exercises. There was also great diversity in outcome measurement. The state of theoretical development regarding the mechanisms by which equine-assisted interventions benefit the veteran population is currently underdeveloped. Studies provided insufficient detail with respect to the description of the intervention, reasons for attrition, and the dose-response relationship. CONCLUSIONS: Scientific development of equine-assisted interventions targeting psychosocial outcomes among veterans is warranted to establish their efficacy. Targeted outcomes should be expanded, including outcomes more closely aligned with the nature of polytraumatic injuries. Future research must also emphasize the theoretical development of equine-assisted interventions for veterans and thoroughly describe the participants, components of the intervention, factors contributing to attrition, and optimal dose-response relationships.