Reliability and validity of the function in sitting test in nonambulatory individuals with multiple sclerosis

Abstract

Poor seated balance negatively impacts the performance of activities of daily living in nonambulatory individuals with multiple sclerosis (MS) and is frequently a target of rehabilitation interventions. However, there is a lack of clinical measures of seated balance in nonambulatory individuals with MS, thus limiting evaluation of rehabilitation treatments. The aim of this investigation is to determine the reliability and concurrent validity of the Function in Sitting Test (FIST) as a measure of sitting balance in nonambulatory individuals with MS. Twenty nonambulatory individuals with MS [mean age±SD=56.8±10.9 years, women n=15 (75%), mean MS duration±SD=17.8±9.2 years, mean wheelchair usage duration±SD=5.9±4.7 years] underwent a FIST and posturography assessment. The FIST is a 14-item clinical functional assessment of sitting balance validated in adults with acute stroke. The seated posturography assessment involved participants sitting on a force platform without support for 30 s. On the basis of the center of pressure trajectory obtained from the force platform software, two force platform outcomes were quantified: sway area (mm) of the center of pressure and virtual time to contact to the functional boundary (seconds). Internal consistency reliability was assessed using Cronbach's coefficient-α. The test-retest reliability was evaluated using the intraclass correlation coefficient (ICC). Concurrent validity of the FIST was assessed by Spearman's rank correlation analysis. Cronbach's-α as an index of internal consistency of the FIST was 0.91. The test-retest reliability was found to be excellent (ICC=0.92). The FIST was significantly correlated with virtual time to contact to the functional boundary (ρ=0.487, P=0.02), but not with sway area (ρ=-0.267, P=0.25). The observations provide evidence that the FIST is a reliable and valid tool to assess seated postural control in nonambulatory individuals with MS.

Recommended outcome measures for inpatient rehabilitation of multiple sclerosis are not appropriate for the patients with substantially impaired mobility

“…Recently, there were several publications on novel OMs for persons with severe MS. For example, Sung et al published a validation study of the Function In Sitting Test (FIST), which is a measure of sitting balance that is specifically designed for non-ambulatory MS patients (Sung et al, 2016).…”

“…Based on our results, we suggest the use of 2MWT, as well as FIM-mot and RMI up to moderate MS. Moreover, other potentially interesting OMs, namely the FIST and the 5-STS, could be well suited for severe MS (Møller et al, 2012;Sung et al, 2016). In addition, to better identify therapy responders, one could include in the core set MS-specific, patient-reported outcomes, such as MSIS-29 (Hobart et al, 2001) and MSQoL-54 (Vickrey et al, 1995).…”

Validation of an individualized reduction of falls intervention program among wheelchair and scooter users with multiple sclerosis

“…The FIST is a validated clinical measure that rates participants’ ability to perform 14-seated postural tasks. [14,15]…”

The Validity, Reliability, and Sensitivity of a Smartphone-Based Seated Postural Control Assessment in Wheelchair Users: A Pilot Study

“…There are numerous ways to measure seated postural control. Researchers have developed several clinical measures including, but not limited to, the Function in Sitting Test (Gorman et al, 2010;Sung et al, 2016;Abou et al, 2019), Trunk Control Test (TCT) (Quinzaños et al, 2014), and the Tee-shirt Test (Boswell-Ruys et al, 2009) to assess seated postural control. These clinical measures have few technological requirements but require clinical expertise to perform.…”