Intra-rater reliability of hip abductor isometric strength testing in a standing position in older fallers and non-fallers

The reliability and suitability of strength assessments in frail and pre-frail older adults: recommendations for strength testing in older populations

BACKGROUND

Lifelong strength is fundamental to physical function, health, and quality of life. Reliable appropriate strength assessment measures for older adults play an important role in effective evaluation of baseline ability and exercise prescription to counter disease and disuse. This study aimed to investigate the within-session reliability of maximal isometric knee extension and flexion, hip abduction and adduction, and handgrip strength measures in frail and pre-frail older adults.

METHOD

The study was conducted at a residential care home in Birmingham, UK. All care home residents aged ≥ 65 years; pre-frail or frail according to the Fried Frailty phenotype criteria; able to speak and read English; not currently involved in any other clinical trial; without severe sensory impairments; and with a predicted life expectancy greater than the trial length were eligible. Maximal isometric lower limb testing was performed using specialised resistance training equipment and a portable measurement device, and grip strength was assessed using a portable dynamometer. All eligible participants attended a single testing session and performed three trials per measure. Peak force measures were obtained for analysis. Within-session reliability for each measure was calculated from repeated-measures analysis of variance, intraclass correlation coefficients (ICC), and coefficients of variation (CV) with 95% confidence intervals.

RESULTS

Eleven frail and eleven pre-frail older adults participated in the study. Within-session absolute and relative measures were found to be reliable with the highest overall repeatability indicated between trial 2 and trial 3 for knee extension, hip abduction, and handgrip (CV ≤ 4.65%, ICC ≥ 0.96) with variation evident across all measures, except knee extension, from trial 1 to 2.

CONCLUSIONS

Overall, maximal isometric strength in frail and pre-frail older adults with no previous testing experience can be measured with good to high reliability within their first testing session. An initial two familiarisation trials followed by two measurement trials is recommended to achieve the highest level of overall repeatability.

TRIAL REGISTRATION

The trial was registered with ClinicalTrials.gov: NCT03141879 on 05/05/2017.

Can Clinicians Trust Objective Measures of Hip Muscle Strength From Portable Dynamometers? A Systematic Review With Meta-analysis and Evidence Gap Map of 107 Studies of Reliability and Criterion Validity Using the COSMIN Methodology

OBJECTIVE: To summarize the evidence on reliability and criterion validity of hip muscle strength testing using portable dynamometers. DESIGN: Systematic review with meta-analysis. LITERATURE SEARCH: Five databases were searched from inception to March 2023. STUDY SELECTION CRITERIA: We included studies investigating reliability or criterion validity of hip flexor, extensor, abductor, adductor, or internal/external rotator strength testing with portable dynamometers in injury-free individuals or those with pelvic/lower limb musculoskeletal disorders. DATA SYNTHESIS: We performed meta-analyses for each muscle group, position, and method of fixation. We rated pooled results as sufficient (>75% of studies with correlations ≥0.70), insufficient (>75% of studies with correlations <0.70), or inconsistent (sufficient/insufficient results). We assessed the quality of evidence, created evidence gap maps, and made clinical recommendations. RESULTS: We included a total of 107 studies (reliability 103, validity 14). The intrarater and interrater reliability for hip muscle strength testing across different positions and methods of fixation was sufficient (intraclass correlation coefficient = 0.78-0.96) with low- to high-quality evidence. Criterion validity was less investigated and mostly inconsistent (very low-to moderate-quality evidence) with a wide range of correlations (r = 0.40-0.93). CONCLUSION: Hip muscle strength testing using portable dynamometers is reliable. The use of portable dynamometers as clinical surrogates for measuring strength using an isokinetic dynamometer requires further investigation. Clinicians testing hip muscle strength with portable dynamometers should use external fixation seated for hip flexors, prone or supine for hip extensors, side-lying or supine for abductors and adductors, and prone and seated for internal and external rotators. J Orthop Sports Phys Ther 2023;53(11):655-672. Epub 3 October 2023. doi:10.2519/jospt.2023.12045.

Reliability and Diagnostic Accuracy of Commonly Used Performance Tests Relative to Fall History in Older Persons: A Systematic Review

Background/Objectives

Early detection of fall risk is crucial for targeted fall prevention and rehabilitation. This systematic review facilitates decision-making concerning the optimal choice for a suitable fall risk assessment test for older persons in four different settings. This systematic review provides an overview of reliability and diagnostic accuracy (sensitivity [SE], specificity, likelihood ratios, and post-test probabilities) of commonly used performance measures to assess older persons' fall risk.

Methods

Two reviewers independently screened titles, abstracts, and full texts of all articles identified through a systematic search on the PubMed, Embase, CINAHL, and Web of Science databases. The methodological quality was critically appraised using the Quality Assessment of Diagnostic Accuracy Studies-2 tool and the COSMIN risk of bias tool. Due to a setting-dependent fall risk, four relevant settings were selected for the analyses: 1) community dwelling, 2) nursing home, 3) hospital, and 4) the combined setting of hospitalized and community-dwelling persons.

Results

Recommendations for diagnostic accuracy can be made for the specific settings: setting 1) mini-balance evaluation system test, timed up and go test with fast speed (TUG FAST), cognitive TUG FAST, functional reach test, and fast gait speed; 2) TUG at usual speed; 3) none of the included tests; and 4) some hip muscle strength and hand grip strength tests might be recommended.

Conclusion

The review's results are applicable for use in clinical practice, both on a population and on an individual level for patients and caregivers. Most measures' reliability is sufficient. However, the included tests' discriminative ability is not optimal for clinical use in relevant settings. The low sample sizes of most of the included studies and a limited amount of studies in all but the community-dwelling setting hinder us from making strong recommendations.

Reliability and validity of an adapted hip abductor strength measure as a potential new fall risk assessment for older persons: a study protocol

Background

Persons aged ≥ 65 years are currently the world’s fastest growing age group. An important complication of age is the increasing risk of falls. Falls have multifactorial etiology and modifiable risk factors open for interventions in prevention and rehabilitation, are of high interest. In this context, strong hip abductors seem to be important to prevent falls. A newly adapted measurement device to measure hip abductor strength (HAS) in a closed chain position was developed. We aim to assess feasibility, intra- and inter-tester reliability and construct and criterion validity of the new measure.

Methods

In two subsequent parts a feasibility, reliability and validity study with an adapted measurement instrument for the assessment of HAS (index test) in a closed chain position in persons aged ≥ 65 years will be conducted. Part I investigates feasibility of the measure in clinical settings as well as reliability of the new HAS test (n = 26). Part II evaluates construct and criterion validity (n = 169). Construct validity will be assessed cross-sectional, criterion validity by comparison with prospectively followed up fall history for 12 months (external criterion) and other functional fall risk assessments (Short Physical Performance Battery, Timed Up and Go test, usual gait speed and hand grip strength).

Discussion

Results of feasibility, will give insight in its applicability in daily clinical life and clinimetric properties will show if measurements of HAS in a closed chain position should be encouraged to include in fall risk assessments in older adults.