"During my research of people with Parkinson's Disease, I gained an appreciation for GAITRite because of the simplicity and efficiency of data collection and analysis, and the comprehensive technical and research support provided to me by the company. This experience led me to make GAITRite the first purchase for my movement sciences lab."
- David A, Lehman, PT, PhD, Associate Professor, Department of Physical Therapy, Tennessee State University

Quantitative gait dysfunction and risk of cognitive decline and dementia
Joe Verghese; Cuiling Wang; Richard B Lipton; Roee Holtzer; Xiaonan Xue; J Neurol Neurosurg Psychiatry 2007;78:929-935.

Background: Identifying quantitative gait markers of preclinical dementia may lead to new insights into early disease stages, improve diagnostic assessments and identify new preventive strategies.

Objective: To examine the relationship of quantitative gait parameters to decline in specific cognitive domains as well as the risk of developing dementia in older adults.

Methods: We conducted a prospective cohort study nested within a community based ageing study. Of the 427 subjects aged 70 years and older with quantitative gait assessments, 399 were dementia-free at baseline.

Results: Over 5 years of follow-up (median 2 years), 33 subjects developed dementia. Factor analysis was used to reduce eight baseline quantitative gait parameters to three independent factors representing pace, rhythm and variability. In linear models, a 1 point increase on the rhythm factor was associated with further memory decline (by 107%), whereas the pace factor was associated with decline on executive function measured by the digit symbol substitution (by 29%) and letter fluency (by 92%) tests. In Cox models adjusted for age, sex and education, a 1 point increase on baseline rhythm (hazard ratio (HR) 1.48; 95% CI 1.03 to 2.14) and variability factor scores (HR 1.37; 95% CI 1.05 to 1.78) was associated with increased risk of dementia. The pace factor predicted the risk of developing vascular dementia (HR 1.60; 95% CI 1.06 to 2.41).

Conclusion: Our findings indicate that quantitative gait measures predict future risk of cognitive decline and dementia in initially non-demented older adults.

Reliability of Spatiotemporal Gait Outcome Measures in Huntington's Disease
Ashwini K. Rao, EdD, OTR; Lori Quinn, EdD, PT; Karen S. Marder, MD, MPH
Movement Disorders, Vol. 20, No. 8, 2005

Abstract: Gait impairments are very important in Huntington's disease (HD), because loss of independence in gait is an important predictor of nursing home placement. Given this importance, it is imperative to test reliable and sensitive outcome measures that can be tested easily in various clinical environments. Here, we examined the test-retest reliability of gait outcome measures using the GAITRite instrumented carpet. We tested 12 subjects with HD and 12 age-matched controls in two separate sessions. At each session, subjects walked across the GAITRite carpet at a comfortable speed. We used the intraclass correlation coefficient (ICC) and coefficient of variation (CoV) to measure test-retest reliability. Reliability was very high for all outcome measures (velocity, cycle time, stride length, cadence, and base of support), as seen by high ICC scores (0.86 to 0.95) and low CoV scores (0.042-0.102). In addition, the performance across the two subject groups was very different, indicating that the GAITRite is sensitive enough to distinguish between populations. Given that the GAITRite is a relatively inexpensive and portable piece of equipment, it can be used in a wide variety of clinical settings and clinical trials. Our data on high test-retest reliability and sensitivity extends the utility of the GAITRite to the HD population.

Objective Assessment of Gait in Normal-Pressure Hydrocephalus
Williams, MA; Thomas G; de Lateur B; Imteyaz H; Rose JG; Shore WS; Kharkar, S; Rigamonti D
Am J Phys Med Rehabil 2007;86:000-000.

Objectives: Gait abnormalities are an early clinical symptom in normal pressure hydrocephalus (NPH), and subjective improvement in gait after temporary removal of CSF is often used to decide to perform shunt surgery. We investigated objective measures to compare gait before and after CSF drainage and shunt surgery.

Design: Twenty patients and nine controls were studied. Quantitative gait measures were obtained at baseline, after 3 days of controlled CSF drainage, and after shunt surgery. Decision to perform surgery was based on response to drainage, and patients were assigned to shunted or unshunted groups for comparison.

Discussion: ...Ideally, gait assessment in NPH requires a method that combines the simplicity and speed of use necessary for clinical practice with quantitative, reproducible data collection necessary for research. The GAITRite system used in our study is portable and can be used in outpatient and inpatient settings. The validity and reliability of the system in measurement of both averaged and individual temporospatial gait variables has been established. The combination of the GAITRite system for gait analysis and assessment of gait before and after CSF drainage may prove to be an economic, reliable and valid method of selecting patients for shunt surgery. In summary, objective improvement of gait variables in response to controlled CSF drainage is predictive of response to shunt surgery in patients with suspected NPH, and corroborates the selection of such patients on the basis of semi-quantitative scoring systems or expert clinical judgment. The GAITRite system used in this study provides a combination of objective measurement and ease of use that may make it a suitable technique for use in the clinical environment.

The efficacy of quantitative gait analysis by the GAITRite system in evaluation of parkinsonian bradykinesia
Shih-Lin Chiena; Shinn-Zong Linb; Chung-Chao Lianga; Yi-Sheng Soonga; Sheng-Huang Linc; Yu-Loong Hsinc; Chi-Wei Leeb & Shin-Yuan Chenb
Parkinsonism & Related Disorders Volume 12, Issue 7, October 2006, Pages 438-442

Abstract: The aim of this study was to assess whether the GAITRite gait analysis system an effective tool in evaluating parkinsonian bradykinesia. In their best ON and worst OFF states, 13 parkinsonian patients were asked to perform walking trail at their fastest velocity, and to submit to traditional timed tests. Significant correlations existed between OFF-ON improvement in gait parameters and in UPDRS III score (r2=0.59-0.78) except cadence. Among the gait parameters, stride length is the most effective indicator of timed test and UPDRS III score improvements. The GAITRite system is an efficient, yet effective device in evaluating parkinsonian bradykinesia and can be used as a substitute for the traditional timed test.

Reliability and agreement in gait measurements among patients with brain injury
Matti V. Vartiainen; Sarianna Savolainen; Hannu T. Alaranta
Advances in Physiotherapy, January 2008

Abstract: The aim of this study was to evaluate the agreement and test-retest reliability in two walking tests. A consecutive sample of 20 voluntary subjects with brain injury was recruited. Velocity, cadence, right- and left-step length were measured using the GAITRite electronic walkway system and the Ten Meter Walking (TMWT) paper and pencil test. The gait evaluation methods (GAITRite and TMWT) were placed on top of each other. The subjects performed three comfortably paced walking trials approximately 30 min apart. Cronbach's alpha, typical error, change in the mean and Bland-Altman plots, 95% limits of agreement (LOA) were used as statistics of reliability for the agreement between the tests. The intra-class correlation coefficient (ICC), LOA and coefficient of variation (CV) were used as statistics for test-retest reliability. In addition, the objective was to ascertain inter- and intra-rater reliability of these tests. Overall, Cronbach's alpha (0.99) values showed excellent results in both tests. Test-retest and inter-rater ICC values were good (0.95-0.99) in both tests and measured parameters. The absolute reliability results were good in all tests. This study showed acceptable agreement, test-retest and inter-rater reliability of gait measured in both GAITRite and TMW tests in brain-injured patients.