Reliability and concurrent validity of the Microsoft Xbox One Kinect for assessment of standing balance and postural control

doi:10.1016/j.gaitpost.2015.03.005

Gait & Posture

Volume 42, Issue 2, July 2015, Pages 210-213

https://doi.org/10.1016/j.gaitpost.2015.03.005 Get rights and content

Highlights

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The XBox One Kinect (Kinect V2) can be used to measure some aspects of postural control.
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Despite the improved hardware it still has limitations.
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Caution must be taken before implementation as a measurement tool in research.

Abstract

The Microsoft Kinect V2 for Windows™, also known as the Xbox One Kinect, includes new and potentially far improved depth and image sensors which may increase its accuracy for assessing postural control and balance. The aim of this study was to assess the concurrent validity and reliability of kinematic data recorded using a marker-based three dimensional motion analysis (3DMA) system and the Kinect V2 during a variety of static and dynamic balance assessments. Thirty healthy adults performed two sessions, separated by one week, consisting of static standing balance tests under different visual (eyes open vs. closed) and supportive (single limb vs. double limb) conditions, and dynamic balance tests consisting of forward and lateral reach and an assessment of limits of stability. Marker coordinate and joint angle data were concurrently recorded using the Kinect V2 skeletal tracking algorithm and the 3DMA system. Task-specific outcome measures from each system on Day 1 and 2 were compared. Concurrent validity of trunk angle data during the dynamic tasks and anterior–posterior range and path length in the static balance tasks was excellent (Pearson's r > 0.75). In contrast, concurrent validity for medial–lateral range and path length was poor to modest for all trials except single leg eyes closed balance. Within device test–retest reliability was variable; however, the results were generally comparable between devices. In conclusion, the Kinect V2 has the potential to be used as a reliable and valid tool for the assessment of some aspects of balance performance.

Introduction

Since its release the Microsoft Kinect has shown great promise as a physical function assessment tool, and has been used in clinical populations to examine aspects of function such as balance and gait [1], [2]. Validation of the Kinect against a criterion reference typically showed good to excellent associations [3], [4], [5], with a previous study reporting excellent results for static balance and reaching tasks [6]. With the release of the Microsoft Kinect V2, which has improved hardware specifications, and the official software development kit (SDK) the precision and accuracy of anatomical landmark tracking may be improved. This study aimed to examine the validity and reliability of the Kinect V2 for examining outcome measures collected during a variety of static and dynamic balance tests.

Section snippets

Participants

Thirty young, injury-free individuals (age: 22.87 ± 5.08 yrs, height: 172.85 ± 9.11 cm, mass: 68.67 ± 9.15 kg, male = 15) volunteered to participate. Participants wore tight-fitting shorts and an upper body garment that allowed placement of reflective markers. Participants attended two separate testing sessions approximately seven days apart (mean: 7 ± 2 days). This study was approved by the institution's Human Research Ethics Committee and all subjects provided informed consent.

Procedures

Participants performed a

Results

The cross-correlation analysis (Table 2) revealed that for the single leg tests all axes approached or exceeded the threshold for excellent association (r range = 0.70–0.80). In contrast, for the double leg tests there was only modest association (r range = 0.44–0.47) between the two devices. This discrepancy was likely due to the limited range of motion of the anatomical landmarks during these trials, with an association between greater sway range and increased cross-correlation observed (r = 0.63).

Discussion

This study examined the reliability and concurrent validity of the Kinect V2 for assessing static and dynamic balance. Concurrent validity of trunk angle data was excellent for the reach and LOS tests, indicating that the Kinect V2 could be a useful way of easily instrumenting these tests. With respect to the static balance tests, the AP range and path length had excellent concurrent validity in all four tests, but modest reliability in the single leg assessments. This is despite the

Conflict of interest statement

There is no conflict of interest. Author RAC may release software related to this project in the future.

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Citation Excerpt :
The reliability of Kinect was tested with different people at different times by test-retest studies. According to the test results, Kinect 2 can make accurate and reliable measurements enough to be used in rehabilitation [13–22]. When Kinect-based telerehabilitation studies are examined in the literature, it is seen that the studies are mostly aimed at the daily rehabilitation exercises of elderly people.
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Technical noteReliability and concurrent validity of the Microsoft Xbox One Kinect for assessment of standing balance and postural control

Highlights

Abstract

Introduction

Section snippets

Participants

Procedures

Results

Discussion

Conflict of interest statement

Gait Posture

Gait Posture

Gait Posture

J Biomech

Gait Posture

Technical note
Reliability and concurrent validity of the Microsoft Xbox One Kinect for assessment of standing balance and postural control