ORIGINAL ARTICLE The five-repetition sit-to-stand test as a functional outcome measure in COPD Sarah E Jones, 1 Samantha S C Kon, 1 Jane L Canavan, 1 Mehul S Patel, 1 Amy L Clark, 2 Claire M Nolan, 1 Michael I Polkey, 1 William D-C Man 1,2 1 NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, Harefield, UK 2 Harefield Pulmonary Rehabilitation Unit, Royal Brompton & Harefield NHS Foundation Trust, Harefield, UK Correspondence to Sarah E Jones, Department of Respiratory Medicine and Pulmonary Rehabilitation, Harefield Hospital, Hill End Road, Harefield UB9 6JH, UK; s.jones5@rbht.nhs.uk SEJ and SSCK contributed equally. Received 15 March 2013 Revised 24 May 2013 Accepted 29 May 2013 Published Online First 19 June 2013 To cite: Jones SE, Kon SSC, Canavan JL, et al. Thorax 2013;68:1015–1020. ABSTRACT Background Moving from sitting to standing is a common activity of daily living. The five-repetition sit-to- stand test (5STS) is a test of lower limb function that measures the fastest time taken to stand five times from a chair with arms folded. The 5STS has been validated in healthy community-dwelling adults, but data in chronic obstructive pulmonary disease (COPD) populations are lacking. Aims To determine the reliability, validity and responsiveness of the 5STS in patients with COPD. Methods Test-retest and interobserver reliability of the 5STS was measured in 50 patients with COPD. To address construct validity we collected data on the 5STS, exercise capacity (incremental shuttle walk (ISW)), lower limb strength (quadriceps maximum voluntary contraction (QMVC)), health status (St George’s Respiratory Questionnaire (SGRQ)) and composite mortality indices (Age Dyspnoea Obstruction index (ADO), BODE index (iBODE)). Responsiveness was determined by measuring 5STS before and after outpatient pulmonary rehabilitation (PR) in 239 patients. Minimum clinically important difference (MCID) was estimated using anchor-based methods. Results Test-retest and interobserver intraclass correlation coefficients were 0.97 and 0.99, respectively. 5STS time correlated significantly with ISW, QMVC, SGRQ, ADO and iBODE (r=-0.59, -0.38, 0.35, 0.42 and 0.46, respectively; all p<0.001). Median (25th, 75th centiles) 5STS time decreased with PR (Pre: 14.1 (11.5, 21.3) vs Post: 12.4 (10.2, 16.3) s; p<0.001). Using different anchors, a conservative estimate for the MCID was 1.7 s. Conclusions The 5STS is reliable, valid and responsive in patients with COPD with an estimated MCID of 1.7 s. It is a practical functional outcome measure suitable for use in most healthcare settings. INTRODUCTION Exercise performance captures the integrated and multisystemic effects of chronic obstructive pul- monary disease (COPD) and predicts adverse out- comes such as mortality. 1 Although several laboratory-based and field tests have been validated in COPD, limitations exist which may prevent widespread use in some healthcare settings. Laboratory tests are expensive, labour intensive and require specialist equipment, personnel and space. Field walking tests are simpler and cheaper but are still not routinely used in primary, acute or home care settings as they are not practical in terms of space or time. For example, the 6 min walk test (6MWT) requires a 30 m flat course while the incremental shuttle walk (ISW) test requires a 10 m course; both require a repeat walk either on a dif- ferent day or following adequate rest on the same day to account for learning effect. 2 3 There is a need for reliable physical performance tests that are easy and quick to perform in most clinical settings, including the bedside. The sit-to-stand (STS) manoeuvre is a common activity of daily living 4 and is partly dependent on lower limb muscle function and balance. 5 6 Variations of the STS manoeuvre have been adapted as functional performance measures, including time taken to perform a given number of STS manoeuvres 7 or the maximum number of STS manoeuvres in a given time period, usually 30 or 60 s. 89 These have been shown to correlate well with other objective physical performance measures such as Timed Up and Go, gait speed 10 and the 6MWT 9 in healthy older community-living popula- tions as well as patients with stroke, Parkinson’s disease and vestibular disorders. The five-repetition STS test (5STS), which mea- sures the time taken to stand five times from a sitting position as rapidly as possible, is the best described STS test in older adults. Normative values 7 and data on reliability 11 and validity 12 have been well described in healthy older Key messages What is the key question? ▸ Is the five-repetition sit-to-stand test (5STS) a reliable and valid functional outcome measure in patients with chronic obstructive pulmonary disease (COPD)? What is the bottom line? ▸ The 5STS shows excellent reliability, correlates with exercise capacity and lower limb strength and is responsive to pulmonary rehabilitation in COPD. Why read on? ▸ The 5STS is a simple assessment tool that is feasible in all healthcare settings (including the home), and may be a rapid method of assessing changes in exercise capacity in COPD and screening for poor physical functioning individuals. Jones SE, et al. Thorax 2013;68:1015–1020. doi:10.1136/thoraxjnl-2013-203576 1015 Chronic obstructive pulmonary disease on December 17, 2021 by guest. 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