Trial Outcomes & Findings for Physiological Mechanisms of Therapeutic Horseback Riding Intervention Effects in a Psychiatric Population of ASD Youth (NCT NCT04606966)

Study recruitment period began Fall 2020 and concluded Winter 2024. The recruitment process involved sending IRB-approved study information fliers to community agencies serving ASD youth in the two study site states (Colorado and Maine). This recruitment effort was limited to agencies located near each of the state's riding center intervention sites (i.e., Colorado- Denver and north to the state's border and including southern Wyoming; Maine- Portland and surrounding area.)

The following lists reasons enrolled participants were excluded prior to group assignment: * Nonverbal IQ standard score less than 40. * Not meeting criteria for an ASD diagnosis * Not meeting criteria for at least one psychiatric diagnosis (i.e. mood, anxiety, ADHD) * Not receiving medical screening clearance by a medical physician * Having medical or behavioral issues that would prevent participation * Exceeding riding centers' horse safety policy for weight limit.

Physiological Mechanisms of Therapeutic Horseback Riding Intervention Effects in a Psychiatric Population of ASD Youth

The ABC-C is a 58-item caregiver-completed symptom checklist of 5 behavior subscales (i.e. Irritability, Lethargy, Stereotypy, Hyperactivity, Inappropriate Speech) capturing problem behaviors of children and adults with developmental disabilities in community settings on each subscale. THIS MEASURE DOES NOT GENERATE A TOTAL SCORE. Subscale symptom presence and severity scores range from 0 "not a problem" to higher scores indicating more severe problems. The Irritability subscale scores can range between 0-45; The Lethargy subscale scores can range between 0-48; The Stereotypy subscale scores can range between 0-21; The Hyperactivity subscale scores can range between 0-48; The Inappropriate Speech subscale scores can range between 0-12.

The ABC-C is a 58-item caregiver-completed symptom checklist of 5 behavior subscales (i.e. Irritability, Lethargy, Stereotypy, Hyperactivity, Inappropriate Speech) capturing problem behaviors of children and adults with developmental disabilities in community settings on each subscale. THIS MEASURE DOES NOT GENERATE A TOTAL SCORE. Subscale symptom presence and severity scores range from 0 "not a problem" to higher scores indicating more severe problems. The Irritability subscale scores can range between 0-45; The Lethargy subscale scores can range between 0-48; The Stereotypy subscale scores can range between 0-21; The Hyperactivity subscale scores can range between 0-48; The Inappropriate Speech subscale scores can range between 0-12.

The ABC is a 58-item caregiver-completed symptom checklist of 5 behavior subscales (i.e. Irritability, Lethargy, Stereotypy, Hyperactivity, Inappropriate Speech) capturing problem behaviors of children and adults with developmental disabilities in community settings on each subscale. THIS MEASURE DOES NOT GENERATE A TOTAL SCORE. Subscale symptom presence and severity scores range from 0 "not a problem" to higher scores indicating more severe problems. The Irritability subscale scores can range between 0-45; The Lethargy subscale scores can range between 0-48; The Stereotypy subscale scores can range between 0-21; The Hyperactivity subscale scores can range between 0-48; The Inappropriate Speech subscale scores can range between 0-12.

The SOCIAL RESPONSIVENESS SCALE™, Second Edition is a 65-item caregiver-report measure that evaluates social impairments in ASD. The Social Responsiveness Scale™-Second Edition generates raw scores and t-scores for both the combined total score as well as for each of the 5 subscales (social awareness, social cognition, social communication, social motivation, and restricted/repetitive behaviors). NOTE: THIS STUDY USED THE RAW SCORES FOR ANALYSES. The combined Social Responsiveness Scale™-Second Edition total raw scores RANGE from a MINIMUM score of 0 to a MAXIMUM score of 134. HIGHER SCORES ON THIS SCALE INDICATE WORSE OUTCOMES. The Social Awareness raw scores RANGE from a MINIMUM score of 0 to a MAXIMUM score of 19. HIGHER SCORES ON THIS SUBSCALE INDICATE WORSE OUTCOMES. The Social Cognition raw scores RANGE from a MINIMUM score of 0 to a MAXIMUM score of 28. HIGHER SCORES ON THIS SUBSCALE.

The SOCIAL RESPONSIVENESS SCALE™, Second Edition is a 65-item caregiver-report measure that evaluates social impairments in ASD. THIS STUDY USED RAW SCORES FOR ANALYSES. FOR ALL SCALES, HIGHER RAW SCORES INDICATE WORSE OUTCOME. Combined Social Responsiveness Scale total raw scores RANGE from a MINIMUM score of 0 to a MAXIMUM score of 134. Social Awareness raw scores RANGE from a MINIMUM score of 0 to a MAXIMUM score of 19. Social Cognition raw scores RANGE from a MINIMUM score of 0 to a MAXIMUM score of g 28. Social Communication raw scores range from a MINIMUM score of 0 to a MAXIMUM score of 47. Social Motivation raw scores range from a MINIMUM score of 0 to a MAXIMUM score of 26. Restricted/Repetitive Behavior raw scores range from a MINIMUM score of 0 to a MAXIMUM score of 28.

The SOCIAL RESPONSIVENESS SCALE™, Second Edition is a 65-item caregiver-report measure that evaluates social impairments in ASD. THIS STUDY USED RAW SCORES FOR ANALYSES. FOR ALL SCALES, HIGHER RAW SCORES INDICATE WORSE OUTCOME. Combined Social Responsiveness Scale total raw scores RANGE from a MINIMUM score of 0 to a MAXIMUM score of 134. Social Awareness raw scores RANGE from a MINIMUM score of 0 to a MAXIMUM score of 19. Social Cognition raw scores RANGE from a MINIMUM score of 0 to a MAXIMUM score of 28. Social Communication raw scores range from a MINIMUM score of 0 to a MAXIMUM score of 47. Social Motivation raw scores range from a MINIMUM score of 0 to a MAXIMUM score of 26. Restricted/Repetitive Behavior raw scores range from a MINIMUM score of 0 to a MAXIMUM score of 28.

The EDI is a 30-item caregiver report form that is comprised of a 24-item EDI Reactivity scale and 6-item Dysphoria scales that are scored separately. The Reactivity subscale captures intense, rapidly escalating, sustained, and poorly regulated negative emotional reactions. The Dysphoria scale captures minimal positive affect and motivation along with the presence of nervousness and sadness. Each scale (Reactivity and Dysphoria) raw scores were converted into t-scores using the Clinical (ASD) sample t-score with a mean= 50 and standard deviation = 10 (citation here). The theoretical bound of both subscale t-scores is 20-80 and higher scores indicate more symptom severity.

The EDI is a 30-item caregiver report form that is comprised of a 24-item EDI Reactivity scale and 6-item Dysphoria scales that are scored separately. The Reactivity subscale captures intense, rapidly escalating, sustained, and poorly regulated negative emotional reactions. The Dysphoria scale captures minimal positive affect and motivation along with the presence of nervousness and sadness. Each scale (Reactivity and Dysphoria) raw scores were converted into t-scores using the Clinical (ASD) sample t-score with a mean= 50 and standard deviation = 10 (citation here). The theoretical bound of both subscale t-scores is 20-80 and higher scores indicate more symptom severity.

The EDI is a 30-item caregiver report form that is comprised of a 24-item EDI Reactivity scale and 6-item Dysphoria scales that are scored separately. The Reactivity subscale captures intense, rapidly escalating, sustained, and poorly regulated negative emotional reactions. The Dysphoria scale captures minimal positive affect and motivation along with the presence of nervousness and sadness. For each scale (Reactivity and Dysphoria), raw scores were converted into t-scores using the Clinical (ASD) sample t-score with a mean= 50 and standard deviation = 10 (citation here). The theoretical bound of both subscale t-scores is 20-80 and higher scores indicate more symptom severity.

Systematic Analysis of Language Transcripts (SALT) provides standardized guidelines to elicit, transcribe, and analyze language samples from individuals, including those with ASD. The SALT also provides language analysis programs to compute a vocabulary diversity quotient from transcripts entered into the database. A five-minute expressive language sample was elicited by each participant and recorded by the project's Speech Therapist, blind to participants' randomized group assignment. Participant's total number of words and total number of different words is dependent on their verbal output during the 5-minute speech sample and use of more words during the language sample is optimal.

Systematic Analysis of Language Transcripts (SALT) provides standardized guidelines to elicit, transcribe, and analyze language samples from individuals, including those with ASD. The SALT also provides language analysis programs to compute a vocabulary diversity quotient from transcripts entered into the database. A five-minute expressive language sample was elicited by each participant and recorded by the project's Speech Therapist, blind to participants' randomized group assignment. Participant's total number of words and total number of different words is dependent on their verbal output during the 5-minute speech sample and use of more words during the language sample is optimal.

Systematic Analysis of Language Transcripts (SALT) provides standardized guidelines to elicit, transcribe, and analyze language samples from individuals, including those with ASD. The SALT also provides language analysis programs to compute a vocabulary diversity quotient from transcripts entered into the database. A five-minute expressive language sample was elicited by each participant and recorded by the project's Speech Therapist, blind to participants' randomized group assignment. Participant's total number of words and total number of different words is dependent on their verbal output during the 5-minute speech sample and use of more words during the language sample is optimal.

The WHOQOL-BREF is a validated self-report instrument consisting of 26 Likert-scale items rated on a five-point scale. Four primary domain scores of well-being were calculated from 24 items: physical health (7 items), psychological health (6 items), social relationships (3 items), and environment (8 items). Domain scores were transformed to a 0-100 scale by dividing the raw domain score by the potential maximum score and multiplying by 100, with higher scores indicating better quality of life; these transformed scores are reported here. Therefore, for each of the scales (i.e., physical health, psychological health, social relationships, and environment) the minimum score is a value of 0 and the maximum score is a value of 100 with higher scores indicating better quality of life.

The WHOQOL-BREF is a validated self-report instrument consisting of 26 Likert-scale items rated on a five-point scale. Four primary domain scores of well-being were calculated from 24 items: physical health (7 items), psychological health (6 items), social relationships (3 items), and environment (8 items). Domain scores were transformed to a 0-100 scale by dividing the raw domain score by the potential maximum score and multiplying by 100, with higher scores indicating better quality of life; these transformed scores are reported here. Therefore, for each of the scales (i.e., physical health, psychological health, social relationships, and environment) the minimum score is a value of 0 and the maximum score is a value of 100 with higher scores indicating better quality of life.

The WHOQOL-BREF is a validated self-report instrument consisting of 26 Likert-scale items rated on a five-point scale. Four primary domain scores of well-being were calculated from 24 items: physical health (7 items), psychological health (6 items), social relationships (3 items), and environment (8 items). Domain scores were transformed to a 0-100 scale by dividing the raw domain score by the potential maximum score and multiplying by 100, with higher scores indicating better quality of life; these transformed scores are reported here.Therefore, for each of the scales (i.e., physical health, psychological health, social relationships, and environment) the minimum score is a value of 0 and the maximum score is a value of 100 with higher scores indicating better quality of life.

Each participant donated approximately 0.5-1 mL of saliva at the riding center within 5 minutes before (i.e., "Pre-session") and 20 minutes after (i.e., "Post-Session) each THR or BA group session weeks 1-10. Salivary cortisol collected pre- and -post intervention activities were analyzed separately.

Each participant donated approximately 0.5-1 mL of saliva at the riding center within 5 minutes before and 20 minutes after each THR or BA group session weeks 1-10. Salivary cortisol collected pre- and -post intervention activities were analyzed.

Each participant donated approximately 0.5-1 mL of saliva at the riding center within 5 minutes before and 20 minutes after each THR or BA group session weeks 1-10. Salivary cortisol collected pre- and -post intervention activities were analyzed.

The Shimmer3 cardiac (ECG) monitor was used in this study. This cardiovascular monitor was specifically developed to record electrocardiographic signals while participants are active or in motion. The form factor is compact (about 2" by 1"), lightweight (13g), and designed to wear continuously and unobtrusively. It samples ECG and HRV up to 2,048 Hz, which is sufficient for research.125 It has a built-in accelerometer for quantifying periods of physical activity, necessary to identify signal artifacts in post-processing. Participants' Shimmer3 ECG assessments were measured continuously during the intervention lesson. Unit of measure is ms log-10 transformed.

The Shimmer3 cardiac (ECG) monitor was used in this study. This cardiovascular monitor was specifically developed to record electrocardiographic signals while participants are active or in motion. The form factor is compact (about 2" by 1"), lightweight (13g), and designed to wear continuously and unobtrusively. It samples ECG and HRV up to 2,048 Hz, which is sufficient for research.125 It has a built-in accelerometer for quantifying periods of physical activity, necessary to identify signal artifacts in post-processing. Participants' Shimmer3 ECG assessments were measured continuously during the intervention lesson. Unit of measure is ms log-10 transformed.

The Shimmer3 cardiac (ECG) monitor was used in this study. This cardiovascular monitor was specifically developed to record electrocardiographic signals while participants are active or in motion. The form factor is compact (about 2" by 1"), lightweight (13g), and designed to wear continuously and unobtrusively. It samples ECG and HRV up to 2,048 Hz, which is sufficient for research.125 It has a built-in accelerometer for quantifying periods of physical activity, necessary to identify signal artifacts in post-processing. Participants' Shimmer3 ECG assessments were measured continuously during the intervention lesson. Unit of measure is ms log-10 transformed.

The Shimmer3 EDA monitor was used to record EDA from participants' ventral area of the wrist using alternating current imperceptibly applied to the skin through two hypoallergenic, durable, and replaceable Ag electrodes. As dry non-adhesive electrodes tend to move on the skin surface during physical activity and destroy signal quality, disposable adhesive electrodes with an appropriate salinity (e.g., 0.5%; EL507) were used. EDA sampling frequency in the Shimmer3 is 4 Hz with a 0.01- 100uS range. Peripheral skin temperature was recorded by the Shimmer3 EDA monitor at 4 Hz in the -40 to 115-Celsius range using optical infrared thermopile. The Shimmer3 EDA recorded motion-based activity up to ±8g at 32 Hz using 3-axis accelerometry. Participants' Shimmer3 EDA assessments were measured during the intervention lesson. Unit of measure is microsiemens.

The Shimmer3 EDA monitor was used to record EDA from participants' ventral area of the wrist using alternating current imperceptibly applied to the skin through two hypoallergenic, durable, and replaceable Ag electrodes. As dry non-adhesive electrodes tend to move on the skin surface during physical activity and destroy signal quality, disposable adhesive electrodes with an appropriate salinity (e.g., 0.5%; EL507) were used. EDA sampling frequency in the Shimmer3 is 4 Hz with a 0.01- 100uS range. Peripheral skin temperature was recorded by the Shimmer3 EDA monitor at 4 Hz in the -40 to 115-Celsius range using optical infrared thermopile. The Shimmer3 EDA recorded motion-based activity up to ±8g at 32 Hz using 3-axis accelerometry. Participants' Shimmer3 EDA assessments were measured continuously during the intervention lesson. Unit of measure is microsiemens.

The Shimmer3 EDA monitor was used to record EDA from participants' ventral area of the wrist using alternating current imperceptibly applied to the skin through two hypoallergenic, durable, and replaceable Ag electrodes. As dry non-adhesive electrodes tend to move on the skin surface during physical activity and destroy signal quality, disposable adhesive electrodes with an appropriate salinity (e.g., 0.5%; EL507) were used. EDA sampling frequency in the Shimmer3 is 4 Hz with a 0.01- 100uS range. Peripheral skin temperature was recorded by the Shimmer3 EDA monitor at 4 Hz in the -40 to 115-Celsius range using optical infrared thermopile. The Shimmer3 EDA recorded motion-based activity up to ±8g at 32 Hz using 3-axis accelerometry. Participants' Shimmer3 EDA assessments were measured continuously during the intervention lesson. Unit of measure is microsiemens.