Reliability and Minimal Detectable Change for a Smartphone-Based Motor-Cognitive Assessment: Implications for Concussion Management

Abstract

Our purpose was to investigate the reliability and minimal detectable change characteristics of a smartphone-based assessment of single- and dual-task gait and cognitive performance. Uninjured adolescent athletes (n = 17; mean age = 16.6, SD = 1.3 y; 47% female) completed assessments initially and again 4 weeks later. The authors collected data via an automated smartphone-based application while participants completed a series of tasks under (1) single-task cognitive, (2) single-task gait, and (3) dual-task cognitive-gait conditions. The cognitive task was a series of continuous auditory Stroop cues. Average gait speed was consistent between testing sessions in single-task (0.98, SD = 0.21 vs 0.96, SD = 0.19 m/s; P = .60; r = .89) and dual-task (0.92, SD = 0.22 vs 0.89, SD = 0.22 m/s; P = .37; r = .88) conditions. Response accuracy was moderately consistent between assessments in single-task standing (82.3% accurate, SD = 17.9% vs 84.6% accurate, SD = 20.1%; P = .64; r = .52) and dual-task gait (89.4% accurate, SD = 15.9% vs 85.8% accurate, SD = 20.2%; P = .23; r = .81) conditions. Our results indicate automated motor-cognitive dual-task outcomes obtained within a smartphone-based assessment are consistent across a 1-month period. Further research is required to understand how this assessment performs in the setting of sport-related concussion. Given the relative reliability of values obtained, a smartphone-based evaluation may be considered for use to evaluate changes across time among adolescents, postconcussion.

A Multifaceted Approach to Interpreting Reaction Time Deficits After Adolescent Concussion

“…6,7,13 Thus, clinically feasible methods of quantifying RT across treatment settings and recovery need to be identified. Furthermore, while dual-task gait deficits persist despite improvement in subjective symptom reports, 14,15 quantifying RT in both static and dynamic positions may allow clinicians to understand how patients perform in sport-like conditions, where attention must be divided across motor and cognitive domains.…”

“…5 Simple RT measures involve a response to a single stimulus, such as a clinical drop stick RT test, or a simple stimulus-response task. 7,15,16 Procedural RT measures involve multiple stimuli and responses, such as a standing auditory Stroop test where stimuli are provided and responses recorded repeatedly over a period of time. 15 Dual task RT measures, such as a dual task gait assessment in which an individual is asked to walk while completing a concurrent mental task, provide insight to motor-cognitive functioning.…”

“…7,15,16 Procedural RT measures involve multiple stimuli and responses, such as a standing auditory Stroop test where stimuli are provided and responses recorded repeatedly over a period of time. 15 Dual task RT measures, such as a dual task gait assessment in which an individual is asked to walk while completing a concurrent mental task, provide insight to motor-cognitive functioning. 15 Given the many options to assess RT, investigating a multifaceted battery of different RT assessments within a sample of injured and uninjured individuals may help clinicians understand the potential strengths and limitations of different approaches.…”

“…15 Dual task RT measures, such as a dual task gait assessment in which an individual is asked to walk while completing a concurrent mental task, provide insight to motor-cognitive functioning. 15 Given the many options to assess RT, investigating a multifaceted battery of different RT assessments within a sample of injured and uninjured individuals may help clinicians understand the potential strengths and limitations of different approaches. Therefore, the primary purpose of our study was to examine the utility of four different RT measurement approaches (clinical drop stick, simple stimulus-response, singletask Stroop, and dual-task Stroop) to differentiate between adolescents tested within 2 weeks of concussion and uninjured control adolescents.…”

“…Through headphones attached to the smartphone, patients were instructed to audibly identify the pitch of the word, not the word itself, throughout each 30 second trial. 15 A smartphone application (IMPROVE, Control One, LLC) was used to elicit the Stroop task audio recordings and calculate response time to each detect the response accuracy of the participant as either "high," "low," or unknown. 15,16 The smartphone O n l i n e F i r s t recorded the time in ms between each auditory cue and verbal response.…”