Farlie M.K.1,2, Keating J.L.2, Molloy E.2, Haines T.P.1,2
1Monash Health, Allied Health Research Unit, Melbourne, Australia, 2Monash University, Faculty Medicine Nursing & Health Science, Melbourne, Australia
Background: Falls and fall-related injury is a key cause of morbidity and mortality in older adults world-wide. Balance exercise has been shown to improve balance in older adults, however, there are currently no validated measurement tools to rate the intensity of balance exercise. This is in contrast with other forms of exercise such as strength and aerobic exercise where validated intensity measures are well established.
Purpose: Without a validated balance exercise intensity measure, optimal balance exercise prescription is yet to be determined. This study aimed to develop and refine two scales, one that measures balance exercise intensity from the perspective of therapists and the other from the perspective of exercisers.
Methods: Three studies were conducted to (1) identify possible scale items, (2) develop two scale prototypes, to measure balance exercise intensity from the perspective of therapists and exercisers respectively, and (3) a cohort study to field test the scale prototypes. The cohort study trialed the use of the Balance Intensity Scale (BIS)-Therapist and BIS-Exerciser prototypes by therapists and exercisers using their respective scales to rate the exercisers performing balance exercises of varying levels of difficulty in a clinical setting. Analytical methods utilized in the scale development and refinement process included interpretive description, Rasch and factor analysis.
Results: The observational study of exercisers (n=20) identified eleven therapist-rated, and 8 exerciser-rated balance challenge markers. Therapist consultation (n=73) informed modification to the 18 therapist-rated items. Exerciser consultation (n=5) informed modification of 13 exerciser-rated items. The clinical trial (n=110 exercisers, n=32 therapists) generated n=320 balance task assessments. Factor analysis and single parameter Rasch analysis were used to determine the final item set for both scales. Both scales have strong internal consistency (Cronbachs alpha=0.80 and 0.81 respectively).
Conclusion(s): The BIS-Therapist and BIS-Exerciser have now been validated in their use with older adults from a range of diagnostic groups performing balance exercises. Further testing of reliability and validity of the refined scale in specific populations can now be conducted.
Implications: The development of balance intensity scales for therapists and exercisers has broad reaching implications for the study of balance exercise prescription. With a valid measure of balance exercise intensity, the optimal dosage of balance exercise to improve balance and prevent falls can now be further investigated. Similar to strength and aerobic training, it will now be possible to investigate optimal frequency and duration of balance exercise training at varying intensities to determine the most effective dose-response relationship for balance exercise training and falls prevention interventions.
Funding acknowledgements: MKF: JCMTF Grant (2011); Monash University Maxwell King PhD Scholarship (2016)
TPH: NHMRC Career Development Fellowships (Population Health: 2010-2017)
TPH: NHMRC Career Development Fellowships (Population Health: 2010-2017)
Topic: Older people
Ethics approval: Monash Health and Monash University Human Research Ethics Committee approval number 11030B
All authors, affiliations and abstracts have been published as submitted.
