980 resultados para Measurement Error
Resumo:
This paper reports on the motor and functional outcomes of 20 children with developmental coordination disorder (DCD) aged 4-8 years consecutively referred to a pediatric physiotherapy service. Children with a Movement ABC (M-ABC) score less than the 15th percentile, and with no concurrent medical, sensory, physical, intellectual or neurological impairments, were recruited. The Motor Assessment Outcomes Model (MAOM) [Coster and Haley, Infants and Young Children 4 (1992) 11] provided the theoretical base for measurement selection, and preliminary findings at the activities and participation levels of the model are reported in this article. Children with DCD performed at the lower end of the normal range on the Pea-body Developmental Motor Scales (fine motor total score) (M = 85.65, SD = 12.23). Performance on the Visual Motor Integration Test (VMI) standard scores was within the average range (M = 96.15, SD = 10.69). Videotaped observations of the children's writing and cutting indicated that 29% were left-handed and that a large proportion of all children (31%) utilized unusual pencil grasp patterns and immature prehension of scissors. Measurement at the participation level involved use of the Pictorial Scale of Perceived Competence and Social Acceptance (PCSA) and Pediatric Evaluation of Disability Inventory (PEDI). Overall, these young children rated themselves towards the more competent and accepted end of the PCSA over the dimensions of physical and cognitive competence and peer and maternal acceptance. The PEDI revealed generally average performance on social (M = 49.98, SD = 16.62) and mobility function (M = 54.71, SD = 3.99), however, self-care function was below the average range for age (M = 38.01, SD = 12.19). The utility of the MAOM as a framework for comprehensive measurement of functional and motor outcomes of DCD in young children is discussed. (C) 2003 Elsevier B.V. All rights reserved.
Resumo:
Background and Purpose. This study evaluated an electromyographic technique for the measurement of muscle activity of the deep cervical flexor (DCF) muscles. Electromyographic signals were detected from the DCF, sternocleidomastoid (SCM), and anterior scalene (AS) muscles during performance of the craniocervical flexion (CCF) test, which involves performing 5 stages of increasing craniocervical flexion range of motion-the anatomical action of the DCF muscles. Subjects. Ten volunteers without known pathology or impairment participated in this study. Methods. Root-mean-square (RMS) values were calculated for the DCF, SCM, and AS muscles during performance of the CCF test. Myoelectric signals were recorded from the DCF muscles using bipolar electrodes placed over the posterior oropharyngeal wall. Reliability estimates of normalized RMS values were obtained by evaluating intraclass correlation coefficients and the normalized standard error of the mean (SEM). Results. A linear relationship was evident between the amplitude of DCF muscle activity and the incremental stages of the CCF test (F=239.04, df=36, P<.0001). Normalized SEMs in the range 6.7% to 10.3% were obtained for the normalized RMS values for the DCF muscles, providing evidence of reliability for these variables. Discussion and Conclusion. This approach for obtaining a direct measure of the DCF muscles, which differs from those previously used, may be useful for the examination of these muscles in future electromyographic applications.
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Measurement while drilling (MWD) techniques can provide a useful tool to aid drill and blast engineers in open cut mining. By avoiding time consuming tasks such as scan-lines and rock sample collection for laboratory tests, MWD techniques can not only save time but also improve the reliability of the blast design by providing the drill and blast engineer with the information specially tailored for use. While most mines use a standard blast pattern and charge per blasthole, based on a single rock factor for the entire bench or blast region, information derived from the MWD parameters can improve the blast design by providing more accurate rock properties for each individual blasthole. From this, decisions can be made on the most appropriate type and amount of explosive charge to place in a per blasthole or to optimise the inter-hole timing detonation time of different decks and blastholes. Where real-time calculations are feasible, the system could extend the present blast design even be used to determine the placement of subsequent holes towards a more appropriate blasthole pattern design like asymmetrical blasting.
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This paper reports a study that explored a new construct: climate of fear. We hypothesised that climate of fear would vary across work sites within organisations, but not across organisations. This is in contrast a to measures of organisational culture, which were expected to vary both within and across organisations. To test our hypotheses, we developed a new 13-item measure of perceived fear in organisations and tested it in 20 sites across two organisations (N = 209). Culture variables measured were innovative leadership culture, and communication culture. Results were that climate of fear did vary across sites in both organisations, while differences across organisations were not significant, as we anticipated. Organisational culture, however, varied between the organisations, and within one of the organisations. The climate of fear scale exhibited acceptable psychometric properties.
Resumo:
To investigate the ability of ultrasonography to estimate musactivity, we measured architectural parameters (pennation angles, fascicle lengths, and muscle thickness) of several human muscles (tibialis anterior, biceps brachii, brachialis, transversus abdominis, obliquus internus abdominis, and obliquus externus abdominis) during isometric contractions of from 0 to 100% maximal voluntary contraction (MVC). Concurrently, electromyographic (EMG) activity was measured with surface (tibialis anterior only) or fine-wire electrodes. Most architectural parameters changed markedly with contractions up to 30% MVC but changed little at higher levels of contraction. Thus, ultrasound imaging can be used to detect low levels of muscle activity but cannot discriminate between moderate and strong contractions. Ultrasound measures could reliably detect changes in EMG of as little as 4% MVC (biceps muscle thickness), 5% MVC (brachialis muscle thickness), or 9% MVC (tibialis anterior pennation angle). They were generally less sensitive to changes in abdominal muscle activity, but it was possible to reliably detect contractions of 12% MVC in transversus abdominis (muscle length) and 22% MVC in obliquus internus (muscle thickness). Obliquus externus abdominis thickness did not change consistently with muscle contraction, so ultrasound measures of thickness cannot be used to detect activity of this muscle. Ultrasound imaging can thus provide a non-invasive method of detecting isometric muscle contractions of certain individual muscles.
Resumo:
Background: Although early in life there is little discernible difference in bone mass between boys and girls, at puberty sex differences are observed. It is uncertain if these differences represent differences in bone mass or just differences in anthropometric dimensions. Aim: The study aimed to identify whether sex independently affects bone mineral content (BMC) accrual in growing boys and girls. Three sites are investigated: total body (TB), femoral neck (FN) and lumbar spine (LS). Subjects and methods: 85 boys and 67 girls were assessed annually for seven consecutive years. BMC was assessed by dual energy X-ray absorptiometry (DXA). Biological age was defined as years from age at peak height velocity (PHV). Data were analysed using a hierarchical (random effects) modelling approach. Results: When biological age, body size and body composition were controlled, boys had statistically significantly higher TB and FN BMC at all maturity levels (p < 0.05). No independent sex differences were found at the LS (p > 0.05). Conclusion: Although a statistical significant sex effect is observed, it is less than the error of the measurement, and thus sex difference are debatable. In general, sex difference are explained by anthropometric difference
Resumo:
Time motion analysis is extensively used to assess the demands of team sports. At present there is only limited information on the reliability of measurements using this analysis tool. The aim of this study was to establish the reliability of an individual observer's time motion analysis of rugby union. Ten elite level rugby players were individually tracked in Southern Hemisphere Super 12 matches using a digital video camera. The video footage was subsequently analysed by a single researcher on two occasions one month apart. The test-retest reliability was quantified as the typical error of measurement (TEM) and rated as either good (10% TEM). The total time spent in the individual movements of walking, jogging, striding, sprinting, static exertion and being stationary had moderate to poor reliability (5.8-11.1% TEM). The frequency of individual movements had good to poor reliability (4.3-13.6% TEM), while the mean duration of individual movements had moderate reliability (7.1-9.3% TEM). For the individual observer in the present investigation, time motion analysis was shown to be moderately reliable as an evaluation tool for examining the movement patterns of players in competitive rugby. These reliability values should be considered when assessing the movement patterns of rugby players within competition.
Resumo:
The purpose of this study was to evaluate and establish the mean values of IOP in healthy adult sheep using an applanation tonometer. Information on age, sex, and breed was obtained for all animals included in this study. Twenty five healthy sheep (Ovis aries), of the same breed (Texel), male or female, with three years of age, received an ophthalmic examination in both eyes, including pupillary reflexes, Schirmer tear test, slit lamp biomicroscopy, and fluorescein staining. For all ophthalmic testing, animals were gently physically restrained, with no pressure in the jugular area and the eyelids were carefully open. IOP was measured by applanation tonometry (Tonopen XL). The same examiner performed the tonometry; measurements were taken three times for each eye, and their average was recorded as the IOP of the animal. Statistical analysis was performed using paired t-test and values of P < 0.05 were considered significant. The mean intraocular pressure in the whole group of 50 eyes was of 16.36 +/- 2.19 mm Hg. The mean (SD) IOP in the right eye was of 15.96 +/- 2.02 mm Hg, while the mean (SD) IOP in the left eye was of 16.76 +/- 2.32 mm Hg. Significant differences in IOP were not found between right and left eyes. The applanation tonometer was adequate for measuring the intraocular pressure in sheep. Reference data will assist in diagnosing testing for ophthalmic disease in sheep, as¹ well as promote further studies in this area.
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Performance measurement of police services is complicated by ambiguous and complex goal- and objectives-setting, and by the difficulties of measuring outputs. This article looks at the organizational and management changes being made in Portuguese police forces. The authors fill a gap in the literature on performance measurement in Portugal by taking a national approach to the study of how law enforcement agencies are introducing new management accounting changes. The article therefore widens the debate on performance measurement and performance improvements in law enforcement.
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A hierarchical matrix is an efficient data-sparse representation of a matrix, especially useful for large dimensional problems. It consists of low-rank subblocks leading to low memory requirements as well as inexpensive computational costs. In this work, we discuss the use of the hierarchical matrix technique in the numerical solution of a large scale eigenvalue problem arising from a finite rank discretization of an integral operator. The operator is of convolution type, it is defined through the first exponential-integral function and, hence, it is weakly singular. We develop analytical expressions for the approximate degenerate kernels and deduce error upper bounds for these approximations. Some computational results illustrating the efficiency and robustness of the approach are presented.
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Websites are, nowadays, the face of institutions, but they are often neglected, especially when it comes to contents. In the present paper, we put forth an investigation work whose final goal is the development of a model for the measurement of data quality in institutional websites for health units. To that end, we have carried out a bibliographic review of the available approaches for the evaluation of website content quality, in order to identify the most recurrent dimensions and the attributes, and we are currently carrying out a Delphi Method process, presently in its second stage, with the purpose of reaching an adequate set of attributes for the measurement of content quality.