title: Introducing a new definition of a near fall: intra-rater and inter-rater reliability.
abstract: Near falls (NFs) are more frequent than falls, and may occur before falls, potentially predicting fall risk. As such, identification of a NF is important. We aimed to assess intra and inter-rater reliability of the traditional definition of a NF and to demonstrate the potential utility of a new definition. To this end, 10 older adults, 10 idiopathic elderly fallers, and 10 patients with Parkinson's disease (PD) walked in an obstacle course while wearing a safety harness. All walks were videotaped. Forty-nine video segments were extracted to create 2 clips each of 8.48 min. Four raters scored each event using the traditional definition and, two weeks later, using the new definition. A fifth rater used only the new definition. Intra-rater reliability was determined using Kappa (K) statistics and inter-rater reliability was determined using ICC. Using the traditional definition, three raters had poor intra-rater reliability (K<0.054, p>0.137) and one rater had moderate intra-rater reliability (K=0.624, p<0.001). With the traditional definition, inter-rater reliability between the four raters was moderate (ICC=0.667, p<0.001). In contrast, the new NF definition showed high intra-rater (K>0.601, p<0.001) and excellent inter-rater reliability (ICC=0.815, p<0.001). A priori, it is easy to distinguish falls from usual walking and NFs, but it is more challenging to distinguish NFs from obstacle negotiation and usual walking. Therefore, a more precise definition of NF is required. The results of the present study suggest that the proposed new definition increases intra and inter-rater reliability, a critical step for using NFs to quantify fall risk.
authors: Movement Disorders Unit, Department of Neurology, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel; RiVERS Lab, Department of Rehabilitation and Movement Science, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
authors: I
authors: I
authors: Maidan
authors: T
authors: T
authors: Freedman
authors: R
authors: R
authors: Tzemah
authors: N
authors: N
authors: Giladi
authors: A
authors: A
authors: Mirelman
authors: J M
authors: JM
authors: Hausdorff
mesh_terms: D000058:Accidental Falls; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D005260:Female; D005684:Gait / Q000502:physiology; D020233:Gait Disorders, Neurologic / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010300:Parkinson Disease / Q000150:complications / Q000503:physiopathology*; D015203:Reproducibility of Results; D014741:Video Recording
keywords: Aging; Fall risk; Gait; Near falls
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