title: The 1-min sit-to-stand test--A simple functional capacity test in cystic fibrosis?
abstract: BACKGROUND
  We aimed to assess the measurement properties and the minimal important difference (MID) of the 1-min sit-to-stand (STS) test in cystic fibrosis (CF).
  
  
  METHODS
  Patients with CF were tested during a pulmonary rehabilitation program. Five STS tests were performed during the program; two tests at the beginning (STS0 and STS1) and three tests at the end (STS2a-2c). Exercise capacity, pulmonary function, and health-related quality of life (HRQoL) and patient-reported health status were measured at the beginning and end of the program. We calculated overall mean, standard deviation, coefficient of variation (CV), and intraclass correlation coefficient (ICC) of the STS test. The MID was calculated using anchor-based and distributional methods.
  
  
  RESULTS
  Fourteen participants (8 female, mean age 30.4±6.1years) were included. STS test performance increased significantly from STS0 to STS1 indicative of a learning effect. Test-retest reliability for the subsequent STS2a-2c tests was excellent (ICC 0.98, 95% CI 0.96-0.99). The estimated MID for the STS test was 5 repetitions. STS test performance was responsive to change (effect size of 0.97) and correlated with exercise capacity (r=0.63-0.73) and with the physical functioning HRQoL scale (r=0.72).
  
  
  CONCLUSIONS
  The 1-min STS test appears to be a reliable, valid, and feasible test to measure functional capacity in patients with CF.
authors.affiliation: Epidemiology, Biostatistics and Prevention Institute, University of Zürich, Zurich, Switzerland. Electronic address: thomas.radtke@uzh.ch.
authors.forename: Thomas
authors.initials: T
authors.lastname: Radtke
authors.affiliation: Epidemiology, Biostatistics and Prevention Institute, University of Zürich, Zurich, Switzerland.
authors.forename: Milo A
authors.initials: MA
authors.lastname: Puhan
authors.affiliation: Paediatric Department, Julius-Maximilians University Würzburg, Germany.
authors.forename: Helge
authors.initials: H
authors.lastname: Hebestreit
authors.affiliation: Epidemiology, Biostatistics and Prevention Institute, University of Zürich, Zurich, Switzerland.
authors.forename: Susi
authors.initials: S
authors.lastname: Kriemler
mesh_terms: D000328:Adult; D003550:Cystic Fibrosis / Q000503:physiopathology / Q000534:rehabilitation*; D005080:Exercise Test / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006304:Health Status; D006801:Humans; D008297:Male; D011788:Quality of Life; D015203:Reproducibility of Results; D013997:Time Factors
keywords: Exercise testing; Functional capacity; Minimal important difference; Muscle function