title: Test-retest strength reliability: hand-held dynamometry in community-dwelling elderly fallers.
abstract: OBJECTIVE
  To determine the reliability of a standardized protocol by using a hand-held dynamometer (HHD) to measure lower-extremity strength in community-dwelling elderly fallers.
  
  
  METHODS
  Within-session test-retest reliability of the HHD.
  
  
  METHODS
  Balance laboratory of a university.
  
  
  METHODS
  A convenience sample of 41 community-dwelling elders (61-90y) who fell at least once in the previous year.
  
  
  METHODS
  The strengths of 8 lower-extremity muscle groups bilaterally were tested twice, with an intervening rest period of 15 seconds.
  
  
  METHODS
  Maximal isometric force.
  
  
  RESULTS
  Test-retest intraclass correlation coefficients (ICCs) were high, generally ranging from.95 to.99 for 1 trial (ICC(2,1)) and from.97 to 1.00 for the mean of 2 trials (ICC(2,2)). There were no significant differences in strength values across trials (P>.05). Men had significantly greater strength than women across all muscle groups (P>.05). Right knee extensor strength demonstrated the largest trial-to-trial difference,.54 kg using a single measurement and.39 kg using the mean of both measurements. Among the 3 lower-extremity muscle groups, the ankle showed higher a coefficient of variation (CV=5.1%-7.4%) than the knee (CV=4.6%-5.1%) or the hip (CV=4.2%-6.3%) when using 1 measure.
  
  
  CONCLUSIONS
  By using an HHD and a standardized measurement protocol, a novice tester can obtain reliable lower-extremity strength values in community-dwelling elderly fallers.
authors.affiliation: School of Physical Therapy, Texas Woman's University, Houston, TX, USA. cywang@tccn.edu.tw
authors.forename: Ching-Yi
authors.initials: CY
authors.lastname: Wang
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Olson
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Protas
mesh_terms: D000058:Accidental Falls; D000368:Aged; D000704:Analysis of Variance; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D007537:Isometric Contraction; D007866:Leg; D008297:Male; D015999:Multivariate Analysis; D018908:Muscle Weakness / Q000175:diagnosis*; D026741:Physical Therapy Modalities / Q000295:instrumentation*; D015203:Reproducibility of Results