Publication Cover
Physiotherapy Theory and Practice
An International Journal of Physical Therapy
Volume 38, 2022 - Issue 13
1,497
Views
3
CrossRef citations to date
0
Altmetric
Descriptive Report

The functional reach test in people with multiple sclerosis: a reliability and validity study

ORCID Icon, ORCID Icon, ORCID Icon, ORCID Icon, ORCID Icon, ORCID Icon, ORCID Icon, ORCID Icon, ORCID Icon, ORCID Icon & ORCID Icon show all
Pages 2905-2919 | Received 01 May 2020, Accepted 01 May 2021, Published online: 17 Jun 2021
 

ABSTRACT

Background

Limits of stability (LOS) is a major component of balance dysfunction in people with multiple sclerosis (MS). The functional reach test (FRT) is a clinical LOS assessment; however, its psychometric properties have not been investigated in people with MS yet. Objectives: To investigate: (1) the intrarater, interrater, and test–retest reliability of the FRT in people with MS; (2) the minimum detectable change (MDC) in the FRT distances; (3) the concurrent and discriminant validity of the FRT; and (4) the cutoff distance that best discriminates people with MS from healthy people and fallers from non-fallers with MS.

Methods

Forty-three people with MS and 36 healthy people participated in this study. The FRT was administered along with the instrumented LOS test, Berg Balance Scale, Four Square Step Test, Timed Up and Go Test, and Expanded Disability Status Scale. The FRT was repeated by the same rater after 2 min from the first test session to determine the intrarater reliability and was simultaneously conducted by two independent raters to determine the interrater reliability. The FRT was also repeated after 7–10 days to determine the test–retest reliability. The reliability was quantified using intraclass correlation coefficients (ICC), Bland-Altman plots, and the MDC. The validity was assessed by correlating the FRT distances with the scores of other measures and by comparing the FRT distances between the MS group and healthy people, and between the fallers and non-fallers in the MS group.

Results

The FRT demonstrated good to excellent intrarater, interrater, and test–retest reliability with an ICC (3,1) of 0.80–0.88 (p < .001), an ICC (3,2) of 0.94–0.97 (p < .001), an ICC (2,3) of 0.84–0.86 (p < .001), respectively. Bland–Altman analyses showed no systematic bias between the assessments. The MDC was 8.28 centimeters. The FRT was correlated with the other outcome measures (correlation coefficients ranged from 0.31 to 0.79, p < .05 for all). Significant differences in the FRT distances were found between people with MS and healthy people; however, no significant difference was found between the fallers and non-fallers with MS (p < .001 and p = .09, respectively). The cutoff distance of 35.5 centimeters best discriminates healthy people from people with MS while of 28.5 centimeters did not discriminate between the fallers and non-fallers with MS.

Conclusions

The FRT is a reliable, valid, and easy-to-administer tool for assessing LOS in people with MS.

Acknowledgments

The authors gratefully acknowledge the individuals who participated in this study.

Declaration of interest

The authors report no conflict of interest.

Log in via your institution

Log in to Taylor & Francis Online

PDF download + Online access

  • 48 hours access to article PDF & online version
  • Article PDF can be downloaded
  • Article PDF can be printed
USD 65.00 Add to cart

Issue Purchase

  • 30 days online access to complete issue
  • Article PDFs can be downloaded
  • Article PDFs can be printed
USD 325.00 Add to cart

* Local tax will be added as applicable

Related Research

People also read lists articles that other readers of this article have read.

Recommended articles lists articles that we recommend and is powered by our AI driven recommendation engine.

Cited by lists all citing articles based on Crossref citations.
Articles with the Crossref icon will open in a new tab.