A novel assessment for Readiness Evaluation during Simulated Dismounted Operations: A reliability study

Abstract

Objective: To determine the intersession reliability of the Readiness Evaluation during Simulated Dismounted Operations (REDOp), a novel ecologically-based assessment for injured Service Members, provide minimal detectable change values, and normative reference range values. To evaluate the ability to differentiate performance limitations between able-bodied and injured individuals using the REDOp.

Design: Repeated measures design and between group comparison.

Setting: Outpatient rehabilitative care setting.

Participants: Service Members who were able-bodied (n = 32) or sustained a traumatic lower extremity injury (n = 22).

Interventions: During the REDOp, individuals walked over variable terrain as speed and incline progressively increased; they engaged targets; and carried military gear.

Main outcome measures: Endurance measured using total distance traveled; walking stability measured using range of full-body angular momentum; and shooting accuracy, precision, reaction time and acquisition time.

Results: Intersession reliability analyses were conducted on a sub-group of 18 able-bodied Service Members. Interclass correlation coefficient values were calculated for distance traveled (0.91), range of angular momentum about three axes (0.78-0.93), shooting accuracy (0.61), precision (0.47), reaction time (0.21), and acquisition time (0.77). Service Members with lower extremity injury demonstrated significantly less distance traveled with a median distance of 0.89 km compared to 2.73 km for the able-bodied group (p < 0.001). Service Members with lower extremity injury demonstrated significantly less stability in the frontal and sagittal planes than the able-bodied group (p < 0.001). The primary performance limiter was endurance followed by pain for both groups. There was no evidence of ceiling effects.

Conclusions: The REDOp is a highly reliable, military-relevant assessment that can be used to measure performance and identify deficits across the domains of activity tolerance, gait stability, and shooting performance.

Conflict of interest statement

The authors have read the journal’s policy and the authors of this manuscript have the following competing interests: KAS is currently employed at HARMAN International/Microsoft. However, she had no affiliation with HARMAN International/Microsoft during the execution of the study and all work on the manuscript took place either before beginning employment with HARMAN International/Microsoft or on her own time. This does not alter our adherence to PLOS ONE policies on sharing data and materials. There are no patents, products in development or marketed products associated with this research to declare.

Figures

Fig 1. A participant with a left lower extremity injury engaging targets as part of the Readiness Evaluation during Simulated Dismounted Operations (REDOp) assessment.

Fig 2. Pie charts showing the distributions of the primary reason for stopping and location of pain for the able-bodied and patient participants.

The pain locations are only reported for the participants that stopped because of pain. The counts represent the presence of pain in any of those locations with some participants reporting pain in multiple areas.

Fig 3. Patient data relative the normative reference range for the 8 performance metrics.

The normative values are presented as a blue box plot with whiskers marking the maximum and minimum, small box indicating the 5th and 95th percentiles, and large box containing the median and first and third quartile as box ends. The median patient value is indicated by the red line with individual patient values plotted as red dots. * Indicates a significant difference between groups for the associated measure.