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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Retrospectively registered

Titles & IDs
Public title
Seasonal Variation in Postural Balance in Community Dwelling Older Adults in Tasmania
Scientific title
Older adults (over 60 yrs.) longitudinal observational study over time with no intervention measuring physical fall risks and other determinants of balance that may vary seasonally
Secondary ID [1] 279634 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Fall risk 285434 0
Condition category
Condition code
Musculoskeletal 285615 285615 0 0
Normal musculoskeletal and cartilage development and function

Study type
Patient registry
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Time over a one year period to determine effect of season on physical fall risk factors. Data collected from recruited community dwelling older older adults beween the end of spring 2009 and summer 2010, with participants attending for 5 data collection time points over the study period at approximately 3 monthly intervals (including retest of original season).
Intervention code [1] 283914 0
Not applicable
Comparator / control treatment
Compare baseline and data at the end of each season
Control group

Primary outcome [1] 286177 0
Postural Balance using a force platform (measuring medio-lateral sway range) and dynamic balance using the clinical four square step test
Timepoint [1] 286177 0
Baseline, 3 months, 6 months, 9 months, 12 months
Secondary outcome [1] 295311 0
Serum Vitamin D concentrations
Timepoint [1] 295311 0
Baseline, 3 months, 6 months, 9 months, 12 months, 24 months

Key inclusion criteria
Community dwelling adults over 60 years of age able to ambulate independently
Minimum age
60 Years
Maximum age
85 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Diagnosed kidney and liver disease, vitmain D supplementation over 800iu/day

Study design
Convenience sample
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 284412 0
Name [1] 284412 0
Clifford Craig Medical Research Trust
Address [1] 284412 0
C/- Launceston General Hospital
Charles St
Launceston, 7250, TAS
Country [1] 284412 0
Funding source category [2] 284413 0
Name [2] 284413 0
The Physiotherapy Research Fund
Address [2] 284413 0
Suite 2, 1175 Toorak Rd Camberwell, 3124, VIC
Country [2] 284413 0
Funding source category [3] 284414 0
Name [3] 284414 0
The University of Tasmania
Address [3] 284414 0
Research Office
Private Bag 1
Hobart, 7001, TAS
Country [3] 284414 0
Primary sponsor type
The University of Tasmania
The School of Human Life Sciences
Locked Bag 1320
Launceston, 7250. TAS
Secondary sponsor category [1] 283341 0
Name [1] 283341 0
Address [1] 283341 0
Country [1] 283341 0

Ethics approval
Ethics application status
Ethics committee name [1] 286366 0
Human Research Ethics Committee (Tasmania) Network
Ethics committee address [1] 286366 0
Office of Research Services
University of Tasmania
Private Bag 1
Hobart TAS 7001
Ethics committee country [1] 286366 0
Date submitted for ethics approval [1] 286366 0
Approval date [1] 286366 0
Ethics approval number [1] 286366 0

Brief summary
Balance impairment is an important fall risk factor and increases in range in postural sway in the medio-lateral direction in older adults are associated with increased fall risk and rates. Multivariate analysis reveals serum vitamin D levels as an independent variable associated with postural sway. In individuals with suboptimal levels of vitamin D, postural sway improves after supplementation, independently of changes to fall rate or number of people falling. Both epidemiological and longitudinal studies have shown that vitamin D levels show seasonal variation. Lowest levels of serum vitamin D are recorded towards the end of winter, approximately four weeks after the shortest day of the year. Fall rates have been shown to decrease post supplementation with vitamin D in older adults with insufficient levels (between 22 and 49nmol/L) (RaR 0.72, 95% CI 0.55 to 0.95). As vitamin D varies seasonally, and is related to postural sway, this study investigates whether postural sway varies seasonally and is related to seasonal changes in vitamin D or fall rate.
Trial website
Trial related presentations / publications
Bird, ML and Hill, K and Robertson, I and Ball, MJ and Williams, AD, ‘Vitamin D status, ankle strength and activity show seasonal variation in older adults: relevance for winter falls in higher latitudes’ Age and Ageing (under review)

Conference Presentations
Bird, ML, Hill, KD, Robertson, IK, Ball, MJ, Pittaway, J & Williams, AD, Are seasonal variations in vitamin D and fall rate associated with changes in balance? Australian Physiotherapy Association Conference, 29 October to 1st November, Brisbane, Australia (2011)

Bird, ML, Hill, KD, Robertson, IK, Ball, MJ, Pittaway, J & Williams, AD Seasonal variation in vitamin D, activity and strength. 9th Asia/Oceania Regional Congress of Gerontology and Geriatrics 23-27th October, Melbourne, Australia (2011)
Public notes

Principal investigator
Name 33556 0
Address 33556 0
Country 33556 0
Phone 33556 0
Fax 33556 0
Email 33556 0
Contact person for public queries
Name 16803 0
Marie-Louise Bird
Address 16803 0
The School of Human Life Sciences
The University of Tasmania
Locked Bag 1320
Launceston, TAS 7250
Country 16803 0
Phone 16803 0
+61 3 63243123
Fax 16803 0
+61 3 63243995
Email 16803 0
Contact person for scientific queries
Name 7731 0
Marie-Louise Bird
Address 7731 0
The School of Human Life Sciences
The University of Tasmania
Locked Bag 1320
Launceston, TAS 7250
Country 7731 0
Phone 7731 0
+61 3 63243123
Fax 7731 0
+61 3 63243995
Email 7731 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary