Journal of Rehabilitation Medicine 51-9 | Page 59

J Rehabil Med 2019; 51: 683–691 ORIGINAL REPORT COMPARISON OF MEASUREMENT PROPERTIES OF THREE SHORTENED VERSIONS OF THE BALANCE EVALUATION SYSTEM TEST (BESTest) IN PEOPLE WITH SUBACUTE STROKE Thitimard WINAIRUK, BS 1 , Marco Y. C. PANG, PhD 2 , Vitoon SAENGSIRISUWAN, PhD 3 , Fay B. HORAK, PhD 4 and Rumpa BOONSINSUKH, PhD 1 From the 1 Division of Physical Therapy, Faculty of Physical Therapy, Srinakharinwirot University, Nakhon Nayok, Thailand, 2 Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong, 3 Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand, 4 Department of Neurology, Oregon, Oregon Health and Science University, Beaverton, OR, USA Objectives: To examine the reliability, validity and responsiveness of 3 different short versions of the Balance Evaluation Systems Test (BESTest: S-­ BESTest, Brief-BESTest and Mini-BESTest) in pa- tients with subacute stroke. Design: A prospective cohort study. Participants: Patients with subacute stroke. Methods: Patients were assessed using the full BESTest. Scores of 3 short-form BESTests were later extracted. The intra-rater and inter-rater reliability (n  =  12) were gathered from 5 raters. Concurrent validity was assessed with the Berg Balance Scale (BBS). Floor/ceiling effect, internal responsiveness and external responsiveness with the BBS (n  = 70) were assessed at baseline, 2 weeks and 4 weeks post-rehabilitation. Results and conclusion: All short-form BESTests demonstrated excellent intra-rater and inter-ra- ter reliability (intraclass correlation coefficient (ICC) = 0.95–0.99) and excellent concurrent validity (r = 0.93–0.96). Unlike the Brief-BESTest and Mini- BESTest, the S-BESTest and BESTest had no signifi- cant floor/ceiling effects (< 20%). The standardized response mean of all 4 BESTest versions were large, ranging between 1.19 and 1.57, indicating sufficient internal responsiveness. The area under the curve of the S-BESTest and BESTest were significantly higher than the Brief-BESTest and Mini-BESTest, reflecting better accuracy of the S-BESTest and BE- STest in identifying patients with subacute stroke who had balance improvement using the minimal clinically important difference of 6 and 16 points, respectively. These findings suggest that the S-BE- STest is a short-form BESTest that is appropriate for assessing balance impairments in patients with subacute stroke. Key words: psychometric; physical therapist; postural balan- ce; minimal clinically important difference; patient-reported outcome measures; cerebrovascular disease. Accepted Aug 9, 2019; Epub ahead of print Aug 23, 2019 J Rehabil Med 2019; 51: 683–691 Correspondence address: Rumpa Boonsinsukh, Division of Physical Th- erapy, Faculty of Physical Therapy, Srinakharinwirot University, 63 moo 7 Rungsit-Nakhonnayok, Ongkharuk, Nakhon Nayok, Thailand 26120. E-mail: [email protected] LAY ABSTRACT The aim of this study is to determine which short ver- sions of the Balance Evaluation System Test (BESTest), S-BESTest, Brief-BESTest and Mini-BESTest, are most appropriate for assessing balance impairments in pa- tients with subacute stroke. Participants were patients with subacute stroke: 12 in the reliability assessment and 70 in the validity testing. Patients were assessed using 3 short-form BESTests. All short-form BESTests demonstrated excellent reliability and excellent validi- ty, but the S-BESTest demonstrated better accuracy in identifying patients with subacute stroke who had ba- lance improvement using the cutoff score of 6 points. These findings suggest that the S-BESTest is a short- form BESTest that is appropriate for assessing balance impairments in patients with subacute stroke. P ostural control involves complex co-operation bet- ween several systems to maintain the centre of body mass above its base of support (postural equilibrium) and to control body alignment with reference to itself and the environment (postural orientation). These sys- tems include musculoskeletal components and neuro­ muscular synergies, individual sensory systems and sensory strategies, internal representations, adaptive and anticipatory mechanisms (1). One problem commonly found in individuals post-stroke is postural control or balance impairment. This balance problem can be rela- ted to impairment in each postural control system; for example, prolonged anticipatory reaction time during affected side stepping (2), diminished and delayed adap- tive responses on the affected side (3–5), and abnormal sensory integration (6). To assess balance impairments in patients with stroke, the Berg Balance Scale (BBS), a 14-item functional balance test, is commonly used as a gold standard (7). Although the BBS is useful in reporting the presence of balance impairments, it cannot specify which system of postural control is impaired. The Balance Evaluation System Test (BESTest) is a clinical scale developed to assess the systems of postural control through 6 domains: biomechanical constraints, stability limits/verticality, anticipatory postural adjustments, postural responses, sensory This is an open access article under the CC BY-NC license. www.medicaljournals.se/jrm Journal Compilation © 2019 Foundation of Rehabilitation Information. ISSN 1650-1977 doi: 10.2340/16501977-2589