The Complex Assessment of Military Performance: Dual-task Agility Test-Retest Reliability

Background:

Prior to attending The University of North Carolina at Greensboro for my B.S. in Kinesiology, I was enlisted in the United States Marine Corps Infantry and was stationed at Camp Lejeune, North Carolina from 2012-2016. During this time, I suffered numerous injuries including an mTBI. The primary focus was returning to duty as soon as possible to continue training with my squad as well as deploying with them. There wasn’t an obvious criterion for when I was considered fit for full-duty other than a medical professional telling me which didn’t mean much to me at the time as a 22-year-old with little to no healthcare knowledge. After going through PT school and learning about the research Dr. McCulloch was doing, this was something that sparked my interest. I started by being a pilot test subject for the entire CAMP battery and began becoming more involved with research team communication, development of research materials, data-integrity checks, statistical analysis and presenting the information. My increased involvement during the Fall 2021 semester prompted the strong interest to continue with this research for my capstone that deals specifically with a population in which I belong to.

 

Statement of Need:

Return to duty is important because there is a good chance of under- or over-reporting of symptoms due to the nature of the job, pressure from peers and chain of command, and just the overall culture within the military.¹ Yet, there may be deficits in balance, agility, memory, vision, and dual-or multi-task ability that can last for months or even years after injury.² Only a few objective measures meant for evaluating a concussion injury have included military specific motor skills.^1,3 Other mobility assessments are a relatively basic skill level of mobility that is far from what is required from service members to perform their duties. Data analysis will include looking at single-task motor score (hand-timed), single-task cognitive score (out of 8), dual-task motor (hand-timed), dual-task cognitive (out of 8), single-task sensor and dual-task sensor and with and without the weighted vest for healthy controls. Analyzing the test-retest reliability for the dual-task agility component of CAMP with healthy controls will allow us to determine if it provides clinically meaningful measures without the use of technology to make it feasible for a clinician to administer in order to show stability in test-repetition for ultimate comparison with an impaired group such as post-TBI. A strong test-retest reliability can mitigate the possibility of a learning or practice effect bias and that the agility dual-task component will produce reliable results over time and is critical for interpretation of data in the impaired population. In the healthy controls, there is no impairment yet improvement in the cognitive variables was seen, likely due to them obtaining a strategy from the previous performances of the test. Most cognitive evaluative tools are for single tasks while concussion assessments tend to include one functional domain such as balance, memory, or vision while in static positions. Military service members need to perform complex/complicated tasks under stressful conditions which is what this test is meant to simulate.⁴ Thus, Military service members need functional assessments that combines motor and cognitive tasks with exertion and load and yet none exist. There is currently discussion about concussion guidelines in sport as well as in the military by the DOD and it is stated that the need is there, however little exists in the literature. This is one piece of the big picture and determining the test-retest reliability of the agility dual-task component is the next step in determining its usefulness in the impaired population.

 

Purpose:

To determine the test-retest reliability of the dual-task agility component in a military healthy control group and identify any possible practice effects of the task to aid in interpretation of the results.

 

The Dual-Task Agility Component⁵: 

The Dual-Task Agility component of CAMP is meant to mimic military training to identify possible balance, agility, and/or memory deficits while assessing their ability to manage a “fighting load” to assist in determination of returning to duty post-mTBI. This consists of several trials under single-task and dual-task conditions with a cognitive component (recalling an 8-digit grid coordinate) and a motor component (timed agility course) with and without a weighted-vest (30% bodyweight). The order of the trials is as follows:

1. Single-task cognitive grid coordinate working memory task
2. Single-task agility course familiarization and 1st trial
3. Dual-task agility course with cognitive task (8-digit grid coordinate recalled at end)
4. Single-task agility course with weighted vest
5. Dual-task agility course with weighted vest and cognitive task (8-digit grid coordinate recalled at end)

Cognitive Component: 8-digit grid coordinate working memory

Motor component: Start in ½ kneel, transition kneel to standing, run forward 15’, touch floor marker, turn toward cones, run forward 15’, turn around start cone, run forward 15’, touch floor marker, turn toward cones, run forward 15’ to finish

Dual-task condition: Grid coordinate provided prior to start of the motor component and participant recalls coordinate items after completing the motor component.

This was performed at initial testing and then at a minimum of 4 weeks later during final testing. Data analysis for this component was aimed at determining test-retest reliability to examine possible practice effects in a healthy control population to determine its usefulness in comparison between healthy controls and the mTBI population.

 

Products:

We submitted an abstract to the 2022 Military Health System Research Symposium (MHSRS) in the breakout session of Novel Clinical Assessments and Interventions for mild Traumatic Brain Injury under the focus area of Return-to-Duty with our preliminary data. We are currently awaiting a response on if our abstract has been accepted or not.

MHSRS 2022 Abstract

This poster presentation has been designed to include the updated data and will be adjusted again closer to MHSRS in September 2022 where and when this poster will be presented.

MHSRS Capstone Poster

This website includes mTBI RADAR updates including CAMP and POWAR-TOTAL and has been primarily developed by Courtney Harrison including my assistance.⁶

mTBI RADAR

 

Evaluation Component:

There is no formal evaluation of this specific presentation at this time but will be presented to aspiring PT students, peers and subject matter experts at MHSRS in September. Questioning and critique will be expected and at that time, adjustments can then be made in future research.

 

Self-Assessment:

This experience has been quite the eye opener with what it takes to get research completed. Seeing what it takes to collect data since data collection started about the same time this semester did was a barrier to get past since participants were not exactly lining up out the door to participate. We currently have 14 healthy control subjects that have completed initial and final testing across 3 different sites (Camp Lejeune, Fort Bragg, and Joint Base Lewis-McCord) and several that completed initial testing with some of those lost to the process and will not complete final testing and some that are waiting to complete the final testing session. We were aiming to have around 20 participants by the time MHSRS rolls around and we are moving closer to that number each day. This is what has been hard about this process because we had to wait for data collection to be done then integrity checked and then ran. At the time of abstract submission in February, only 6 participants were able to be included in the statistical analysis which only allowed for the means of each task to be calculated. Now, around the time of submission for this capstone project, we have 14 participants and may have to run statistical analysis again right before poster presentation at MHSRS. This left some time to help Courtney out with her website and any other data monitoring that needed to be done. I was also unable to attend a data collection session at Fort Bragg as scheduling participants is not usually far out and then often reschedule including a participant that I was supposed to observe wound up rescheduling the night before 3 different times. This only further supports that this experience has given me much more of an appreciation for the research process. I will also add that doing a research elective in the semester prior to my capstone has been invaluable. Having background knowledge and experience with this current project has made understanding the data easier and what the objectives of this project were as well.

Overall, I feel this project has been similar to most research that requires flexibility with scheduling which is easier said than done during graduate school especially for someone in my situation (recovering from major surgery, raising 2 children, and taking care of daily home duties). Having a committee has proven to be a great resource for developing adequate materials for my capstone along with suggestions on how to better my deliverables (poster, abstract, etc.). I feel that I could have been better about providing more time for feedback, but my committee did an awesome job getting back to me. Especially considering how many parts of this process is new to me (data collection, statistical analysis, poster creation, etc.), having a committee during this process especially when they have much experience with this process, has been vital to my success.

 

Acknowledgements:

To my faculty advisor Karen McCulloch, PT, PhD, MS, FAPTA, thank you for your continued support and direction through this year long process. Your dedication to my learning and understanding of the research process has been vital to my success and it is greatly cherished. I appreciate the opportunity you have given me to be part of this research that will hopefully fill the gap in the literature and clinical practice. I look forward to possibly presenting our research at MHSRS later this year.

To my committee member Amy Ceccini, PT, DPT, thank you for all of your helpful feedback and assistance with my project. Your responses have been swift yet extremely insightful and have greatly helped me understand this intricate process to better myself as a student and future professional. My project and this research would not have been the same without you!

To my committee member Courtney Harrison, MS, thank you for your assistance with my project and this research. It has been extremely helpful to have your support with the statistical analysis as well as tracking down needed information. You have been the metaphorical ibuprofen to my statistical headaches and my project is more comprehensive because of you!

Bibliography

1.    Scherer MR, Weightman MM, Radomski MV, Davidson LF, McCulloch KL. Returning service members to duty following mild traumatic brain injury: exploring the use of dual-task and multitask assessment methods. Phys Ther. 2013;93(9):1254-1267. doi:10.2522/ptj.20120143
2.    Weightman MM, Bolgla R, McCulloch KL, Peterson MD. Physical therapy recommendations for service members with mild traumatic brain injury. J Head Trauma Rehabil. 2010;25(3):206-218. doi:10.1097/HTR.0b013e3181dc82d3
3.    Fino PC, Weightman MM, Dibble LE, et al. Objective Dual-Task Turning Measures for Return-to-Duty Assessment After Mild Traumatic Brain Injury: The ReTURN Study Protocol. Front Neurol. 2020;11:544812. doi:10.3389/fneur.2020.544812
4.    Kleiner M, Wong L, Dubé A, Wnuk K, Hunter SW, Graham LJ. Dual-Task Assessment Protocols in Concussion Assessment: A Systematic Literature Review. J Orthop Sports Phys Ther. 2018;48(2):87-103. doi:10.2519/jospt.2018.7432
5.    Kress M, Harrison C, Cecchini A, McCulloch K, FAPTA. The Complex Assessment of Military Performance: Dual-Task Agility Test-Retest Reliability.
6.    tarheels.live/mtbiradar/. Accessed April 30, 2022. https://tarheels.live/mtbiradar/