1,721,141 research outputs found
Can we share data? - Kinematic consistency during walking in three different treadmill-based laboratories
No full textBACKGROUND: Three-dimensional gait analysis is crucial for diagnosis and treatment planning. Treadmill-based laboratories efficiently collect 3D gait data over many consecutive steps. Pooling/sharing data across treadmill-based laboratories could enhance clinical utility. However, the inter-laboratory consistency of gait kinematics from treadmill-based systems is unknown. RESEARCH QUESTION: How consistent are lower-limb kinematics of healthy subjects measured in three different treadmill-based gait laboratories? METHODS: Eighteen volunteers (14 women; 27 ± 9 years; BMI 24 ± 3 kg/m ) walked in three treadmill-based laboratories (Motek Medical, The Netherlands) within one week. Per laboratory, participants completed 3-minute walking trials (0.9, 1.1, 1.3 m/s) wearing a non-weight-bearing harness and identical clothes and shoes. The same marker-set (Human-Body Model 2) and virtual reality configurations were used. Statistical Parametric Mapping was used to compare time-normalized kinematic curves of the lower-limb, averaged over 40 steps, between laboratories. Root mean square differences (RMSD) calculated over periods of the gait cycle with statistically significant differences were considered clinically meaningful when > 5°. RESULTS AND SIGNIFICANCE: Kinematics curves from all laboratories followed similar patterns. Only 17 % of all curves displayed clinically relevant differences. These differences included more knee flexion in laboratory 2 compared to the others (RMSD 6.0-8.6°) and less hip flexion in laboratory 3 compared to laboratory 2 (all speeds) and to laboratory 1 (1.3 m/s; RMSD 5.4-6.4°). Reported differences are likely due to varying operator protocols rather than to the measurement system. The findings indicate that inter-laboratory data sharing using such infrastructure is possible but training to align protocols is essential
The Importance of Frailty in Older Adults With Benign Paroxysmal Positioning Vertigo
No full textBackground and Purpose: Even though Benign Paroxysmal Positioning Vertigo (BPPV) is one of the most reported vestibular disorders, its interaction with frailty and postural control in older adults is hardly or not investigated. Methods: Thirty-seven older adults (≥65 years) with a diagnosis of BPPV (oaBPPV) (mean age 73.13 (4.8)) were compared to 22 age-, weight-, and height-matched controls (mean age 73.5 (4.5)). Modified Fried criteria were used to assess frailty. Postural control was assessed with the timed chair stand test, mini Balance Systems Evaluation test (mini-BESTest), a Clinical Test of Sensory Interaction on Balance (CTSIB), and 10-m walk test. Falls were inquired. The Dizziness Handicap Inventory, Falls Efficacy Scale, and 15-item Geriatric Depression Scale assessed dizziness-related handicap, fear of falling, and feelings of depression, respectively. To assess the importance of frailty, all variables were also compared between frail oaBPPV, robust oaBPPV, and robust controls in a sub-analysis. The significance level was set at α = 0.05. Results: oaBPPV reported significantly more multiple falls (P = 0.05) and difficulties to remain standing with increasing task difficulty of the CTSIB (P = 0.004). They were significantly more (pre-)frail compared to controls (P < 0.001). Moreover, frail oaBPPV had a significantly decreased reactive postural control (P < 0.001) and dynamic gait (P < 0.001). Their fear of falling (P < 0.001) and dizziness-related handicap (P < 0.001) were significantly higher compared to robust oaBPPV. Discussion and Conclusions: oaBPPV were less healthy and more (pre-)frail compared to controls, impacting their daily functioning. Future research should investigate whether frailty and postural control were already decreased before the BPPV onset and if this recovers after treatment with repositioning maneuvers or if additional rehabilitation is necessary. Impact Statement: Older adults with Benign Paroxysmal Positional Vertigo (BPPV) can present with an impaired sensory orientation, declined cognition, significantly more multiple falls, and (pre-) frailty compared to controls. Moreover, frail older adults with BPPV also had a significantly decreased reactive postural control and dynamic gait, and an increased odds of falling compared to robust controls. BPPV and frailty appear to be linked with each other, which cannot be ignored in future research and clinicians treating older adults with BPPV.</p
Co-Existing Vestibular Hypofunction Impairs Postural Control, but Not Frailty and Well-Being, in Older Adults with Benign Paroxysmal Positional Vertigo
No full textVestibular hypofunction occurs in 29.5% of older adults with benign paroxysmal positional vertigo (BPPV), but its impact on postural control, well-being and frailty was not studied before. This study compared the well-being, frailty and postural control between older adults with BPPV and vestibular hypofunction (oaBPPV+), and older adults with only BPPV (oaBPPV). Thirty-one older adults (=65 years old) diagnosed with BPPV were recruited. Unilateral vestibular hypofunction was defined as a >25% caloric asymmetry, and bilateral vestibular hypofunction as a total response <6°/s per ear, using bithermal caloric irrigations. The oaBPPV+ group was compared to the oaBPPV group using the measures of well-being (Dizziness Handicap Inventory, Falls Efficacy Scale and 15-item Geriatric Depression Scale), frailty (Modified Fried Criteria), and postural control (timed chair stand test, mini-Balance Evaluation Systems test and Clinical Test of Sensory Interaction on Balance (CTSIB)). Falls and the number of repositioning maneuvers were documented. Significance level was set at a = 0.05. Unilateral vestibular hypofunction was present in 32% of participants, mainly in females ( = 0.04). Bilateral vestibular hypofunction was not found. The oaBPPV+ group ( = 10, mean age 72.5 (4.5)) experienced more comorbidities ( = 0.02) than the oaBPPV group ( = 21, mean age 72.6 (4.9)). Groups did not differ regarding dizziness symptoms ( = 0.46), fear of falling ( = 0.44), depression ( = 0.48), falls ( = 0.08) or frailty ( = 0.36). However, the oaBPPV+ group showed significantly worse postural control under vestibular-dependent conditions ( < 0.001). Despite equally impaired well-being and frailty, the oaBPPV+ group showed greater sensory orientation deficits. Clinicians and researchers should be alert for co-existing vestibular hypofunction in older adults with BPPV, since this may exacerbate their already impaired postural control more than only BPPV
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Several components of postural control are affected by benign paroxysmal positional vertigo but improve after particle-repositioning maneuvers: A systematic review and meta-analysis
No full textObjective Benign Paroxysmal Positional Vertigo is a vestibular disorder causing vertigo and imbalance. This systematic review and meta-analysis aims to explore the impact of benign paroxysmal positioning vertigo and repositioning maneuvers on postural control. Data Sources In September 2024, PubMed, Web of Science, Scopus and reference lists of included studies were systematically searched. Articles comparing measures of postural control between patients and controls, and/or pre- and posttreatment were considered relevant. Methods Study selection, data extraction and identification of risk of bias were done by two researchers. If possible, meta-analysis was performed with Review Manager version 5.4.1 and standardized mean differences were calculated with a random-effects model. Results Twenty-one of the 37 included studies were useful for meta-analyses. Meta-analyses revealed that benign paroxysmal positional vertigo negatively affects perception of verticality (p < .001; SMD = 0.73; 95% CI = [0.39;1.08]) and sensory orientation (p < .001; SMD = -1.66; 95% CI = [-2.08, -1.23]). The perception of verticality (p < .001; SMD = 0.99; 95% CI = [0.76;1.21]) and sensory orientation (p < .001; SMD = -0.77; 95% CI = [-1.11, -0.44]) improved after treatment with repositioning maneuvers. Results of systematic review indicate stability in gait was impaired, vertigo but improve after repositioning maneuvers. Limits of stability were impaired in older patients, but did not improved after repositioning maneuvers. Conclusion Benign paroxysmal positioning vertigo affects several underlying components of postural control. Repositioning maneuvers can significantly improve the related postural control impairments. This may partly explain the increased odds of falling in these patients, and the positive treatment effect of repositioning maneuvers on falls and fear of falling.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by Special Research Fund of the Hasselt University (grant number
BOF20OWB12) and (grant number BOF21OWB02), respectively for Sara Pauwels and Laura Casters and Maastricht University and Ziekenhuis Oost-Limburg Genk
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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