Hip protectors decrease hip fracture risk in elderly nursing home residents: a Bayesian meta-analysis.
OBJECTIVE
To design a Bayesian random effects model for pooling binary outcome data from cluster randomized trials (CRTs) with individually randomized trials (IRTs) and then use this model to determine if hip protectors decrease the risk of hip fracture in elderly nursing home residents.


METHODS
Eight electronic databases were searched; abstracts and papers were reviewed in duplicate. Randomized controlled trials of hip protectors in nursing homes were included. The pooled mean odds ratio (OR) of a hip fracture in an individual allocated to hip protectors with 95% credibility interval (CRI) was calculated.


RESULTS
We included four trials of 1,922 individuals (including three CRTs). The pooled OR of an elderly nursing home resident sustaining one or more hip fractures with hip protector allocation was 0.40 (95% CRI 0.25, 0.61). The model was robust in multiple sensitivity analyses assuming alternative intracluster correlation coefficient values.


CONCLUSIONS
The Bayesian approach may be used in meta-analyses of IRTs and CRTs. Using this approach, we have determined that hip protectors decrease the risk of hip fracture in elderly nursing home residents. Methodologic limitations of the included trials and a possible herd effect in CRTs may have influenced these results.
Sawka
Anna M
AM
Division of Endocrinology and Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada. sawkaam@yahoo.com
Boulos
Pauline
P
Beattie
Karen
K
Papaioannou
Alexandra
A
Gafni
Amiram
A
Cranney
Ann
A
Hanley
David A
DA
Adachi
Jonathan D
JD
Papadimitropoulos
E A
EA
Thabane
Lehana
L
D000368:Aged; D001499:Bayes Theorem; D016000:Cluster Analysis; D006620:Hip Fractures / Q000517:prevention & control*; D006707:Homes for the Aged; D006801:Humans; D009735:Nursing Homes; D010349:Patient Compliance; D011482:Protective Devices; D016032:Randomized Controlled Trials as Topic / Q000379:methods; D012307:Risk Factors; D012984:Software