RT Journal Article SR Electronic T1 The impact of seat height on 1-min sit-to-stand test performance in COPD: a randomised crossover trial JF ERJ Open Research JO erjor FD European Respiratory Society SP 00033-2022 DO 10.1183/23120541.00033-2022 VO 8 IS 3 A1 Valerie Zumbrunnen A1 Thomas F. Riegler A1 Sarah R. Haile A1 Thomas Radtke YR 2022 UL http://openres.ersjournals.com/content/8/3/00033-2022.abstract AB Study question Is there a difference in the number of repetitions in the 1-minute sit-to-stand (1MSTS) test using an individually adapted seat height to 90° knee flexion (1MSTSIND), compared with the commonly used standard chair seat height of 46 cm (1MSTSSTD), in people with COPD?Methods We conducted a single-centre, single-blinded, randomised crossover trial in people with COPD between August 2020 and March 2021 at a specialised rehabilitation clinic in Switzerland. After a learning 1MSTS test, all participants performed two 1MSTS tests in random order on consecutive days. Participants were blinded, as they did not receive detailed information on the testing protocols.Results 49 individuals with COPD (47% female) participated. In a regression model adjusted for sequence period and subject, 1MSTS test performance was lower on 1MSTSIND compared to 1MSTSSTD (−0.78 repetitions, 95% CI −1.47 to −0.11). In a second regression model additionally including the knee angle and an interaction term (1MSTSIND×knee angle), the interaction term was significant: 0.18 (95% CI 0.05 to 0.30). The limits of agreement were between −5.5 and 4 repetitions.Conclusion Although we observed a statistically significant difference between 1MSTSIND and 1MSTSSTD on a population level, the difference is negligible. Further studies may be needed to determine whether individual adaptation of seat height is needed for very tall or short people to ensure a valid assessment of 1MSTS test performance in COPD.Performing the 1MSTS test on an individually adjusted chair versus a standard chair results in fewer repetitions (mean difference −0.78, 95% CI −1.47 to −0.11). However, the difference in repetitions is clinically negligible. https://bit.ly/3Oc8Rvp