Classical Tests (classical + test)

Distribution by Scientific Domains

Terms modified by Classical Tests

  • classical test theory

  • Selected Abstracts

    Diagnostic utility of the Quick Inventory of Depressive Symptomatology (QIDS-C16 and QIDS-SR16) in the elderly

    P. M. Doraiswamy
    Doraiswamy PM, Bernstein IH, Rush AJ, Kyutoku Y, Carmody TJ, Macleod L, Venkatraman S, Burks M, Stegman D, Witte B, Trivedi MH. Diagnostic utility of the Quick Inventory of Depressive Symptomatology (QIDS-C16 and QIDS-SR16) in the elderly. Objective:, To evaluate psychometric properties and comparability ability of the Montgomery-Ĺsberg Depression Rating Scale (MADRS) vs. the Quick Inventory of Depressive Symptomatology,Clinician-rated (QIDS-C16) and Self-report (QIDS-SR16) scales to detect a current major depressive episode in the elderly. Method:, Community and clinic subjects (age ,60 years) were administered the Mini-International Neuropsychiatric Interview (MINI) for DSM-IV and three depression scales randomly. Statistics included classical test and Samejima item response theories, factor analyzes, and receiver operating characteristic methods. Results:, In 229 elderly patients (mean age = 73 years, 39% male, 54% current depression), all three scales were unidimensional and with nearly equal Cronbach , reliability (0.85,0.89). Each scale discriminated persons with major depression from the non-depressed, but the QIDS-C16 was slightly more accurate. Conclusion:, All three tests are valid for detecting geriatric major depression with the QIDS-C16 being slightly better. Self-rated QIDS-SR16 is recommended as a screening tool as it is least expensive and least time consuming. [source]

    Affected-sib-pair test for linkage based on constraints for identical-by-descent distributions corresponding to disease models with imprinting,

    Michael Knapp
    Abstract Holmans' possible triangle test for affected sib pairs has proven to be a powerful tool for linkage analysis. This test is a likelihood-ratio test for which maximization is restricted to the set of possible sharing probabilities. Here, we extend the possible triangle test to take into account genomic imprinting, which is also known as parent-of-origin effect. While the classical test without imprinting looks at whether affected sib pairs share 0, 1, or 2 alleles identical-by-descent, the likelihood-ratio test allowing for imprinting further distinguishes whether the sharing of exactly one allele is through the father or mother. Thus, if the disease gene is indeed subject to imprinting, the extended test presented here can take into account that affecteds will have inherited the mutant allele preferentially from one particular parent. We calculate the sharing probabilities at a marker locus linked to a disease susceptibility locus. Using our formulation, the constraints on these probabilities given by Dudoit and Speed ([1999] Statistics in Genetics; New York: Springer) can easily be verified. Next, we derive the asymptotic distribution of the restricted likelihood-ratio test statistic under the null hypothesis of no linkage, and give LOD-score criteria for various test sizes. We show, for various disease models, that the test allowing for imprinting has significantly higher power to detect linkage if imprinting is indeed present, at the cost of only a small reduction in power in case of no imprinting. Altogether, unlike many methods currently available, our novel model-free sib-pair test adequately models the epigenetic parent-of-origin effect, and will hopefully prove to be a useful tool for the genetic mapping of complex traits. © 2004 Wiley-Liss, Inc. [source]

    Use of the eie-recombinant-chagas-biomanguinhos kit to monitor cure of human chagas' disease

    Edimilson D. Silva
    Abstract We used the EIE-Recombinant-Chagas-Biomanguinhos kit (EIE-Rec kit) developed by the Oswaldo Cruz Foundation, Brazil, to monitor cure of chagasic patients who were treated during the acute phase of T. cruzi infection. Treated patients were previously studied by parasitological and serological tests and classified as cured patients (CP) (n = 10), dissociated patients (DP) (n = 6), and noncured patients (NCP) (n = 6). When sera of these patients were assayed by EIE-Rec kit all sera from NCP and all sera from CP showed positive and negative reactions, respectively. These results were in full agreement with those obtained previously by the classical tests. Two DP showed a positive reaction; the remaining four displayed a negative reaction, similar to that observed in sera from nonchagasic (NCh) individuals, and could therefore be considered CP. Our results suggest that the EIE-Rec kit could be used to monitor the efficacy of Chagas' disease treatment. J. Clin. Lab. Anal. 16:132,136, 2002. © 2002 Wiley-Liss, Inc. [source]

    A look at the abandoned contributions to cosmology of Dirac, Sciama, and Dicke

    ANNALEN DER PHYSIK, Issue 1 2009
    A. Unzicker
    Abstract The separate contributions to cosmology of the above researchers are revisited and a cosmology encompassing their basic ideas is proposed. We study Dirac's article (1938) on the large number hypothesis, Sciama's proposal (1953) of realizing Mach's principle, and Dicke's considerations (1957) on a flat-space representation of general relativity with a variable speed of light (VSL). Dicke's tentative theory can be formulated in a way which is compatible with Sciama's hypothesis on the gravitational constant G. Additionally, such a cosmological model is shown to satisfy Dirac's second ,large number' hypothesis on the total number of particles in the universe being proportional to the square of the epoch. In the same context, Dirac's first hypothesis on an epoch-dependent G , contrary to his prediction , does not necessarily produce a visible time dependence of G. While Dicke's proposal reproduces the classical tests of GR in first approximation, the cosmological redshift is described by a shortening of measuring rods rather than an expansion of space. Since the temporal evolution of the horizon R is governed by , the flatness and horizon problems do not arise in the common form. [source]

    Relationships Among Tests for Censored Data

    Emilio Letón
    Abstract In this paper we will give the relationships of several Score tests and Weighted tests for right censoring data with other classical tests. Special care will be taken with the case of ties and with the kind of estimation of the variance used. After the description of ten tests, a comparative study will be made among them. Finally, an application with a real example will be included. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]