Content » Vol 43, Issue 9

Short communication

Hand-held dynamometry: tester strength is paramount, even in frail populations

Carol A. Stone , Bríd Nolan , Peter G. Lawlor, Rose Anne Kenny
DOI: 10.2340/16501977-0860


Objective: To determine test-retest and inter-rater reliability of hand-held dynamometry when used to measure knee-­extensor strength in patients with advanced cancer.
Subjects: Adults with metastatic or locally advanced cancer recruited from palliative care services to a study of the risk factors for falls.
Methods: Consecutive recruits (n = 30) underwent repeat testing after an interval of 1 h, by the same researcher, to assess test-retest reliability. The subsequent 15 patients underwent retesting by a second researcher. The intra-class correlation coefficient and limits of agreement were calculated.
Results: The test-retest reliability difference between measurements increased with the magnitude of measurement, mean leg strength = 113 N (standard deviation 43. 1), 95% ratio limits of agreement 0. 81–1. 5, intra-class correlation coefficient = 0. 9. The inter-rater testing mean leg strength = 128. 5 N (standard deviation 35. 1), 95% limits of agreement = –57. 24 to 36. 06 N. Intra-class correlation coefficient = 0. 83.
Conclusion: Test-retesting and inter-rater testing yielded high intra-class correlation coefficients, but the limits of agreement were wide. In test-retesting, the difference between tests increased as the magnitude of measurement increased. It has been widely reported that hand-held dynamometry is reliable when used to measure knee-extensor strength in frail or elderly persons. However, our results show that, even in these populations, reliability may be compromised by inadequate tester strength.

Lay Abstract


Do you want to comment on this paper? The comments will show up here and if appropriate the comments will also separately be forwarded to the authors. You need to login/create an account to comment on articles. Click here to login/create an account.