title: Reproducibility of physical performance and physiologic assessments.
abstract: We evaluate the test-retest stability of physical performance and physiologic assessments used in epidemiologic research.
  
  
  METHODS
  Eighty subjects aged 50 to 65 were randomly selected from a probability sample of African Americans for test-retest assessments 5 to 45 days after baseline. Physical performance assessments included grip strength, chair stands, gait speed, and four standing-balance measures. Physiologic assessments included systolic and diastolic blood pressure, height, weight, body fat, and peak expiratory flow.
  
  
  RESULTS
  Intraclass correlations coefficients (ICCs) were .81 for grip strength, .72 for chair stands, .56 for gait speed, .60 for one-leg stand, .52 for semitandem stand, .58 for tandem stand with eyes closed, and .27 for tandem stand with eyes open. Except for blood pressure (ICCs of .51 and .55 for systolic and diastolic), the physiologic assessments had ICCs > .89.
  
  
  CONCLUSIONS
  Additional interviewer training may improve the reproducibility of the tandem stand with eyes open.
authors.affiliation: College of Public Health, The University of Iowa, Iowa City, Iowa 52242, USA. fredric-wolinsky@uiowa.edu
authors.forename: Fredric D
authors.initials: FD
authors.lastname: Wolinsky
authors.forename: Douglas K
authors.initials: DK
authors.lastname: Miller
authors.forename: Elena M
authors.initials: EM
authors.lastname: Andresen
authors.forename: Theodore K
authors.initials: TK
authors.lastname: Malmstrom
authors.forename: J Philip
authors.initials: JP
authors.lastname: Miller
mesh_terms: D000368:Aged; D044383:Black People / Q000706:statistics & numerical data; D001795:Blood Pressure Determination / Q000706:statistics & numerical data*; D005684:Gait; D018737:Hand Strength; D006801:Humans; D008875:Middle Aged; D010808:Physical Examination / Q000706:statistics & numerical data*; D004856:Postural Balance; D015203:Reproducibility of Results; D013997:Time Factors; D001741:Black or African American