Test-retest strength reliability: hand-held dynamometry in community-dwelling elderly fallers.
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.
Wang
Ching-Yi
CY
School of Physical Therapy, Texas Woman's University, Houston, TX, USA. cywang@tccn.edu.tw
Olson
Sharon L
SL
Protas
Elizabeth J
EJ
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