title: Validity and reliability of tools to measure muscle mass, strength, and physical performance in community-dwelling older people: a systematic review.
abstract: BACKGROUND
  This study critically appraises the measurement properties of tools to measure muscle mass, strength, and physical performance in community-dwelling older people. This can support the selection of a valid and reliable set of tools that is feasible for future screening and identification of sarcopenia.
  
  
  METHODS
  The databases PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Cochrane were systematically searched (January 11, 2012). Studies were included if they investigated the measurement properties or feasibility, or both, of tools to measure muscle mass, strength, and physical performance in community-dwelling older people aged ≥60 years. The consensus-based standards for the selection of health status measurement instruments (COSMIN) checklist was used for quality appraisal of the studies.
  
  
  RESULTS
  Sixty-two publications were deemed eligible, including tools for muscle mass (n = 16), muscle strength (n = 15), and physical performance (n = 31). Magnetic resonance imaging, computed tomography, and a 4-compartment model were used as gold standards for muscle mass assessment. Other frequently used measures of muscle mass are dual-energy x-ray and the bioelectrical impedance (BIA); however, reliability data of the BIA are lacking. Handheld dynamometry and gait speed or a short physical performance battery provide a valid and reliable measurement of muscle strength and physical performance, respectively.
  
  
  CONCLUSIONS
  It can be concluded that several tools are available for valid and reliable measurements of muscle mass, strength, and performance in clinical settings. For a home-setting BIA, handheld dynamometry and gait speed or a short physical performance battery are the most valid, reliable, and feasible. The combination of selected instruments and its use for the screening and identification of sarcopenia in community-dwelling older people need further evaluation.
authors.affiliation: School CAPHRI, Department of Health Services Research, Maastricht University, Maastricht, The Netherlands. d.mijnarends@maastrichtuniversity.nl
authors.forename: Donja M
authors.initials: DM
authors.lastname: Mijnarends
authors.forename: Judith M M
authors.initials: JM
authors.lastname: Meijers
authors.forename: Ruud J G
authors.initials: RJ
authors.lastname: Halfens
authors.forename: Sovianne
authors.initials: S
authors.lastname: ter Borg
authors.forename: Yvette C
authors.initials: YC
authors.lastname: Luiking
authors.forename: Sjors
authors.initials: S
authors.lastname: Verlaan
authors.forename: Daniela
authors.initials: D
authors.lastname: Schoberer
authors.forename: Alfonso J
authors.initials: AJ
authors.lastname: Cruz Jentoft
authors.forename: Luc J C
authors.initials: LJ
authors.lastname: van Loon
authors.forename: Jos M G A
authors.initials: JM
authors.lastname: Schols
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D003952:Diagnostic Imaging; D015577:Geriatric Assessment / Q000379:methods*; D006305:Health Status Indicators; D006801:Humans; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D015203:Reproducibility of Results; D055948:Sarcopenia / Q000175:diagnosis*