Elsevier

Gait & Posture

Volume 40, Issue 1, May 2014, Pages 259-261
Gait & Posture

Short Communication
Inter- and intra-rater reliability of the GAITRite system among individuals with sub-acute stroke

https://doi.org/10.1016/j.gaitpost.2014.02.007Get rights and content

Highlights

  • Inter-rater reliability for velocity, step time, and step length were high.

  • Intra-rater reliability was generally greater than inter-rater reliability.

  • Logic checking or standardization of training may reduce potential processing errors.

  • Overall, this study suggests that GAITRite is a reliable assessment tool of gait post-stroke.

Abstract

Technology-based assessment tools with semi-automated processing, such as pressure-sensitive mats used for gait assessment, may be considered to be objective; therefore it may be assumed that rater reliability is not a concern. However, user input is often required and rater reliability must be determined. The purpose of this study was to assess the inter- and intra-rater reliability of spatial and temporal characteristics of gait in stroke patients using the GAITRite system. Forty-six individuals with stroke attending in-patient rehabilitation walked across the pressure-sensitive mat 2–4 times at preferred walking speeds, with or without a gait aid. Five raters independently processed gait data. Three raters re-processed the data after a delay of at least one month. The intraclass correlation coefficients (ICC) and 95% confidence intervals of the ICC were determined for velocity, step time, step length, and step width. Inter-rater reliability for velocity, step time, and step length were high (ICC > 0.90). Intra-rater reliability was generally greater than inter-rater reliability (from 0.81 to >0.99 for inter-rater versus 0.77 to >0.99 for intra-rater reliability). Overall, this study suggests that GAITRite is a reliable assessment tool; however, there still remains subjectivity in processing the data, resulting in no patients with perfect agreement between raters. Additional logic checking within the processing software or standardization of training could help to reduce potential errors in processing.

Introduction

Walking assessment post-stroke is important to inform physiotherapy intervention [1]. Clinical gait assessment can be facilitated by technology, such as pressure-sensitive mats that detect footfall location and timing during walking [2], [3]. This technology objectively calculates measures such as walking speed (a measure of overall gait function) [4], stride-to-stride variability (a measure of dynamic stability control) [5], and symmetry (a measure of gait quality) [6]. The GAITRite walkway is one such pressure-sensitive mat with good test–retest reliability at comfortable walking speeds among individuals with stroke (intraclass correlation coefficients (ICCs): 0.72–0.98) [7], [8]. Since GAITRite is a computerized assessment tool with semi-automated processing it may be assumed that rater reliability is not a concern. However, many individuals with impaired gait, such as those with stroke, exhibit atypical gait patterns. Use of a gait aid, shuffling steps, and heel or toe drag often requires input by the user for data processing (e.g. deleting a portion of or an entire footfall), which may influence reliability. This study aimed to determine inter- and intra-rater reliability of GAITRite for evaluating spatio-temporal gait characteristics post-stroke.

Section snippets

Participants

This study involved secondary analysis of data collected during routine care at Toronto Rehabilitation Institute. We randomly selected 50 patients from a pool of 195 who completed a walking assessment on admission to in-patient stroke rehabilitation. Three patients were subsequently removed due to an insufficient number of footfalls (<18), and one patient was removed because, upon chart review, diagnosis of recent stroke was not confirmed by neuroimaging. Thus, gait data of 46 patients were

Inter-rater and intra-rater reliability

For inter-rater reliability, the mean ICCs for all gait measures were ≥0.94, except step width, which had ICCs of 0.81 and 0.84 for left and right step width, respectively (Table 2). Velocity, step time and step length had acceptable reliability (ICC lower confidence limit > 0.90). ICCs for intra-rater reliability ranged from 0.77 to >0.99. Velocity, step time and step length displayed excellent intra-rater reliability (>0.90). Intra-rater reliability was lower for left and right step width, with

Discussion

This study suggests that GAITRite demonstrates good inter- and intra-rater reliability for spatio-temporal characteristics of gait post-stroke. Nearly all variables met the reliability criterion for application to patient care (ICC > 0.90), except for step width. Previous studies of test–retest reliability of GAITRite within healthy individuals also found that step width was less reliable than other spatio-temporal characteristics of walking [11], [12]. The authors assumed lower step width

Conclusions

Overall, the results suggest that GAITRite is a reliable assessment tool for most gait measures among individuals with sub-acute stroke. Wherever possible, we recommend that the same rater process all GAITRite data. For clinical applications or large research studies this may not be possible; therefore, we recommend that investigators determine inter-rater reliability for individuals who will be processing gait data and for the specific variables of interest prior to generating clinical reports

Conflict of interest statement

The authors declare no conflict of interest.

Acknowledgements

This study was supported by the Heart and Stroke Foundation Canadian Partnership for Stroke Recovery and the Canadian Institutes of Health Research. The authors acknowledge the support of the Toronto Rehabilitation Institute. Equipment and space have been funded with grants from the Canada Foundation for Innovation, Ontario Innovation Trust and the Ministry of Research and Innovation. The views expressed do not necessarily reflect those of the Ministry.

References (15)

There are more references available in the full text version of this article.

Cited by (40)

  • A novel smartphone application is reliable for repeat administration and comparable to the Tekscan Strideway for spatiotemporal gait

    2022, Measurement: Journal of the International Measurement Confederation
    Citation Excerpt :

    For simple at-home measurements of gait, smartphone applications continue to dominate the market given the ability to directly download the application on the individual participants’ smartphone. Modern smartphones with appropriate accelerometers are used by nearly 45% of the world’s population [23] and can be carried in numerous positions on the body to accurately track gait [21–24]. One particular smartphone application, Gait Analyzer [25] created by Control One LLC, has been used with moderate success to analyze gait of pathological and older adult populations [6,10,25,26].

  • Walking test procedures influence speed measurements in individuals with chronic stroke

    2020, Clinical Biomechanics
    Citation Excerpt :

    In the post-stroke population, GAITRite walking speed has concurrent validity with walking speed from a motion capture system (mean difference = 0.005 m/s), functional ambulation (R2 = 0.77), and mobility (R2 = 0.81) (Ng and Hui-Chan, 2005; Price and Choy, 2019; Stokic et al., 2009). GAITRite also has excellent interrater (ICC: 0.997–0.999) and test-retest reliability (ICC = 0.76–0.99) in this population (Kuys et al., 2011; Ng and Hui-Chan, 2005; Wong et al., 2014). Despite the benefits of minimizing stopwatch error, the validity of GAITRite measurements of walking speed may be affected by other test procedures including the distance walked, the vertical clearance required to step onto/off the mat, and the distance over which walking speed is measured relative to the overall test distance.

  • Comparison of underwater gait training and overground gait training for improving the walking and balancing ability of patients with severe hemiplegic stroke: A randomized controlled pilot trial

    2020, Gait and Posture
    Citation Excerpt :

    Gait function was measured by the investigators who were not informed about this study and who did not participate in the patients’ assignment process. All patients started walking 2 m from behind the starting line of the test mat at a comfortable speed and walked 2 m further over the mat [15,16]. The test mat collected data automatically detected by sensors when patients were walking on the mat.

View all citing articles on Scopus
View full text