title: Interrater Reliability of the 6-Minute Walk Test in Women With Hip Fracture.
abstract: OBJECTIVE
  The 6-minute walk test (6MWT) is widely used as a clinical outcome measure. However, the reliability of the 6MWT is unknown in individuals who have recently experienced a hip fracture. The aim of this study was to evaluate the relative and absolute interrater reliability of the 6MWT in individuals with hip fracture.
  
  
  METHODS
  Two senior physical therapy students independently examined a convenience sample of 20 participants in a randomized order. Their assessments were separated by 2 days and followed the guidelines of the American Thoracic Society. Hip fracture-related pain was assessed with the Verbal Ranking Scale.
  
  
  RESULTS
  Participants (all women) with a mean (standard deviation) age of 78.1 (5.9) years performed the test at a mean of 31.5 (5.8) days postsurgery. Of the participants, 10 had a cervical fracture and 10 had a trochanteric fracture. Excellent interrater reliability (intraclass correlation coefficient [ICC2.1] = 0.92; 95% confidence interval, 0.81-0.97) was found, and the standard error of measurement and smallest real difference were calculated to be 21.4 and 59.4 m, respectively. Bland-Altman plots revealed no significant difference (mean of 3.2 [31.5] m, P = .83) between the 2 raters, and no heteroscedasticity was observed (r = -0.196, P = .41). By contrast, participants walked an average of 21.7 (22.5) m longer during the second trial (P = .002). Participants with moderate hip fracture-related pain walked a shorter distance than those with no or light pain during the first test (P = .04), but this was not the case during the second test (P = .25).
  
  
  CONCLUSIONS
  The interrater reliability of the 6MWT is excellent, and changes of more than 21.4 m (group level) and 59.4 m (individual participants with hip fracture) indicate a real change in the 6MWT. Measuring hip fracture-related pain during testing is recommended for individuals with hip fracture who undergo the 6MWT.
authors.affiliation: 1Department of Rehabilitation, Municipality of Lolland, Physical Medicine and Rehabilitation Research-Copenhagen (PMR-C), Maribo, Denmark. 2Research Unit of Musculoskeletal Function and Physiotherapy, Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark. 3Health Sciences Research Centre, University College Lillebaelt, Denmark. 4Department of Rehabilitation, Municipality of Lolland, Maribo, Denmark. 5Physical Medicine and Rehabilitation Research-Copenhagen (PMR-C), Departments of Physiotherapy and Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark.
authors.forename: Jan Arnholtz
authors.initials: JA
authors.lastname: Overgaard
authors.forename: Camilla Marie
authors.initials: CM
authors.lastname: Larsen
authors.forename: Steffen
authors.initials: S
authors.lastname: Holtze
authors.forename: Kenneth
authors.initials: K
authors.lastname: Ockholm
authors.forename: Morten Tange
authors.initials: MT
authors.lastname: Kristensen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005080:Exercise Test; D005260:Female; D006620:Hip Fractures / Q000534:rehabilitation*; D006801:Humans; D015588:Observer Variation; D017063:Outcome Assessment, Health Care; D026741:Physical Therapy Modalities / Q000592:standards*; D015203:Reproducibility of Results; D000070857:Walk Test / Q000592:standards*; D016138:Walking