Development and Evaluation of the Maintenance Office Duty Test: An Alternate Form of the Charge of Quarters Duty Test for Assessing Executive Function After Mild Traumatic Brain Injury to Inform Duty-Readiness After Concussion.

Introduction: After mild traumatic brain injury, service members may experience difficulty with executive functions, which could interfere with return to duty and life roles. Because performance-based multitasking assessments are sensitive to executive dysfunction, a team of military and civilian rehabilitation researchers developed the Charge of Quarters Duty Test (CQDT) to help inform duty readiness after concussion; it is a multitasking test based on a military task scenario that challenges executive functions, such as foresight and planning, set shifting, and prospective memory. Although previous study indicates that CQDT has reliability and known-groups validity, like other multitasking tests, it should not be readministered after rehabilitative care because of learning effects. The purpose of this study was to develop an alternate form of the CQDT and evaluate its equivalence to the CQDT.

Materials and methods: A measurement development study was conducted in which subject matter experts on the study team used an iterative approach to create an alternate form. To evaluate equivalence, a repeated measures design was employed in which each participant performed one or both test versions twice and acted as their own control.

Results: The study team created the Maintenance Office Duty Test (MODT), the alternate form of the CQDT. A convenience sample of 40 adults performed both the MODT and CQDT approximately 2 weeks apart; 4 had a history of military service and 16 had a history of acquired brain injury. We compared mean scores and standard deviations of each test's 4 subscores using matched-pair t-tests and found that scores were not statistically different, suggesting that the 2 tests are equivalent. In addition, matched-pair t-tests were used to compare Time 1 and Time 2 subscores when (1) participants performed the 2 test versions (CQDT and MODT) and (2) participants performed the same test twice. None of the differences in Time 1 and Time 2 subscores were statistically significant when participants performed the 2 test versions. However, when participants performed the same test twice, three of the four Time 1 and Time 2 scores were significantly different, with Time 2 reflecting improved performance and possible learning effects (performance accuracy P = .013; total number of rule breaks P = .015; performance time P = .002).

Conclusions: The MODT appears to be an equivalent form of the CQDT that mitigates learning effects that often accompany performance of multitasking assessments. Having developed and validated the equivalence of the CDQT's alternate form, military rehabilitation clinicians have an expanded set of clinical tools by which to identify possible executive dysfunction and evaluate service members' response to rehabilitative care via pre- and post-rehabilitation testing after mild traumatic brain injury.