Relationship Between Force Steadiness and Functionality in Older Adults: A Systematic Review With Meta-Analysis.

The relevance of force steadiness (FS) in relation to task performance remains unclear. This systematic review with meta-analysis examines the strength of the relationship between FS and the physical task performance aspect of functionality in older adults, focusing on both upper and lower limbs. We conducted a comprehensive search across databases, including MEDLINE, Ovid, CINAHL, Scopus, and Web of Science, up to February 2024. We included correlations from observational or longitudinal studies that provided objective measures of task performance in both healthy and unhealthy older adults. A meta-analysis with robust variance estimation was performed to account for dependencies among effect sizes. Of 1293 studies screened, 21 met the inclusion criteria and 15 contributed data to the meta-analysis. Our findings revealed a moderate, statistically significant relationship between FS and task performance in the upper limbs (r = 0.58, 95% CI [0.49-0.65], p < 0.01) with negligible heterogeneity (I² = 0%). For the lower limbs, the relationship was also moderate (r = 0.45, 95% CI [0.27-0.58], p < 0.01) but with moderate heterogeneity (I² = 50.66%). These results highlight a notable association between FS and physical function in both upper and lower limbs. However, caution is warranted due to the moderate to high risk of bias in 13 studies and evidence of publication bias in studies focused on the upper limbs. Despite these limitations, our study emphasizes the importance of FS in clinical practice and underscores the need for improved methods in measuring FS and its link to physical function. PROSPERO Registration: CRD42021247720.