title: Reliability and Minimum Detectable Change for Common Clinical Physical Function Tests in Sarcopenic Men and Women.
abstract: OBJECTIVE
  To determine the test-retest reliability and minimum detectable change scores for seven common clinical measurements of muscle strength and physical function in a multiethnic sample of sarcopenic, malnourished men and women.
  
  
  METHODS
  Each participant visited the laboratory seven times over 25 to 26 weeks. Reliability was assessed for each measurement from Familiarization 1 to Familiarization 2 (R1), Familiarization 2 to baseline testing (R2), Familiarization 3 to 12-week testing (R3), and Familiarization 4 to 24-week testing (R4).
  
  
  METHODS
  Data were collected during a clinical trial at 23 sites in the United States, Belgium, Italy, Mexico, Poland, Spain, Switzerland, and the United Kingdom.
  
  
  METHODS
  Sarcopenic, malnourished, older adults (N = 257; n = 98 men aged 76.8 ± 6.3, n = 159 women aged 75.9 ± 6.6).
  
  
  METHODS
  During each visit, participants completed the Short Physical Performance Battery (SPBB) and isometric handgrip and isokinetic leg extensor and flexor strength testing at a slow (1.05 rad/s) and fast (3.15 rad/s) velocity.
  
  
  RESULTS
  Handgrip strength, gait speed, SPPB score, and isokinetic leg extension and flexion peak torque (PT) had intraclass correlation coefficients (ICCs) that were significantly greater than 0 (all ≥0.59) at R1, R2, R3, and R4, although most of these variables demonstrated systematic increases at R1, and several exhibited systematic variability beyond the baseline testing session.
  
  
  CONCLUSIONS
  The ICCs and standard errors of the measurement (SEMs) generally improved with familiarization, which emphasizes the need for at least one familiarization trial for these measurements in sarcopenic, malnourished older adults. A three tier-approach to interpreting the clinical importance of statistically significant results that includes null hypothesis testing, examination and interpretation of the effect magnitude, and comparison of individual changes with the SEM and minimum detectable change of the measurements used is recommended.
authors.affiliation: Applied Neuromuscular Physiology Laboratory, Oklahoma State University, Stillwater, Oklahoma.
authors.forename: Nathaniel D M
authors.initials: NDM
authors.lastname: Jenkins
authors.affiliation: Neuromuscular Research and Imaging Laboratory, University of Nebraska-Lincoln, Nebraska, Oklahoma.
authors.forename: Joel T
authors.initials: JT
authors.lastname: Cramer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005684:Gait / Q000502:physiology; D015577:Geriatric Assessment; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D007866:Leg / Q000503:physiopathology; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D009748:Nutrition Disorders / Q000150:complications; D015203:Reproducibility of Results; D055948:Sarcopenia / Q000503:physiopathology*; D019415:Torque
keywords: aging; muscle strength; physical function; sarcopenia; sensitivity