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Statistical competencies for medical research learners: What is fundamental?
- Felicity T. Enders, Christopher J. Lindsell, Leah J. Welty, Emma K. T. Benn, Susan M. Perkins, Matthew S. Mayo, Mohammad H. Rahbar, Kelley M. Kidwell, Sally W. Thurston, Heidi Spratt, Steven C. Grambow, Joseph Larson, Rickey E. Carter, Brad H. Pollock, Robert A. Oster
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- Journal:
- Journal of Clinical and Translational Science / Volume 1 / Issue 3 / June 2017
- Published online by Cambridge University Press:
- 09 May 2017, pp. 146-152
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Introduction
It is increasingly essential for medical researchers to be literate in statistics, but the requisite degree of literacy is not the same for every statistical competency in translational research. Statistical competency can range from ‘fundamental’ (necessary for all) to ‘specialized’ (necessary for only some). In this study, we determine the degree to which each competency is fundamental or specialized.
MethodsWe surveyed members of 4 professional organizations, targeting doctorally trained biostatisticians and epidemiologists who taught statistics to medical research learners in the past 5 years. Respondents rated 24 educational competencies on a 5-point Likert scale anchored by ‘fundamental’ and ‘specialized.’
ResultsThere were 112 responses. Nineteen of 24 competencies were fundamental. The competencies considered most fundamental were assessing sources of bias and variation (95%), recognizing one’s own limits with regard to statistics (93%), identifying the strengths, and limitations of study designs (93%). The least endorsed items were meta-analysis (34%) and stopping rules (18%).
ConclusionWe have identified the statistical competencies needed by all medical researchers. These competencies should be considered when designing statistical curricula for medical researchers and should inform which topics are taught in graduate programs and evidence-based medicine courses where learners need to read and understand the medical research literature.
Contributors
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. 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Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. 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Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
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- 05 August 2012
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- 20 September 2010, pp xi-xliv
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A New Laboratory Designed to Provide an Optimum Environment for Aberration-Corrected Electron Microscopes
- L. F. Allard, D. A. Blom, T. A. Nolan, W. H. Sides, L. J. Degenhardt, J. A. Mayo, W. Vogen, E. St. Romain
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- Microscopy and Microanalysis / Volume 8 / Issue S02 / August 2002
- Published online by Cambridge University Press:
- 01 August 2002, pp. 478-479
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- August 2002
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Microstructural Evaluation of Zno Thin Films Deposited by Mocvd
- C. R. Gorla, S. Liang, N. Emanetoglu, W. E. Mayo, Y. Lu
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- MRS Online Proceedings Library Archive / Volume 482 / 1997
- Published online by Cambridge University Press:
- 10 February 2011, 131
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- 1997
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ZnO films are being used in many emerging technologies such as high frequency RF filters, substrate/buffer layer for GaN deposition, and as active layers in blue-UV LEDs and lasers. These applications require epitaxial films with high structural quality. In the present paper, results on the structure of ZnO films deposited by MOCVD on c-plane and r-plane sapphire substrates are presented. These films have been investigated by XRD, SEM and TEM. X-ray phi-scans show that the films have a single epitaxial relationship with each substrate orientation. (11.0) ZnO grows on (01.2) sapphire (r-plane), while (00.1) oriented films grow on (00.1) sapphire (c-plane). Smooth films are obtained on r-sapphire, while films with a columnar morphology are obtained on c-sapphire. Based on the morphology of the columnar grains grown on c-sapphire, it is expected that the films are oxygen terminated. The interface between ZnO and sapphire is atomically sharp as observed by HRTEM. Misfit dislocations at the interface between ZnO and r-sapphire have been observed. Grain boundaries between coalescing islands during film growth are the main type of defects. Under certain conditions, very long whiskers were observed to grow by the VLS mechanism. By modifying our system, we have been able to prevent the growth of these whiskers.
The Role of Impurities in LP-MOCVD Grown Gallium Nitride
- C.Y. Hwang, Y. Li, M. J. Schurman, W. E. Mayo, Y. Lu, R. A. Stall
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- MRS Online Proceedings Library Archive / Volume 395 / 1995
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- 21 February 2011, 521
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- 1995
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We have investigated the relationship of the Hall electron mobility to the background carrier concentration in low pressure MOCVD grown GaN. The highest electron mobility (400 cm2 /V•s) of the unintentionally doped GaN was obtained at a carrier concentration of 1×1017 cm−3 and samples with carrier concentrations lower than this exhibited lower mobilities. SIMS analysis shows C and O concentrations in the range of 2–3×1016 cm−3 and H in the 2–3×1017 cm−3 range. Structural defects, stoichiometry and impurities in the GaN films grown under different conditions are investigated to understand their relationship to the electron Hall mobilities. In particular, different growth temperatures and pressures were used to grow undoped GaN and modify the background doping effect of the impurities.
Characterization of Gallium Nitride Grown on (0001) Sapphire by Plasma-Enhanced Atomic Layer Epitaxy
- C.-Y. Hwang, P. Lu, W. E. Mayo, Y. Lut, H. Liut
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- MRS Online Proceedings Library Archive / Volume 326 / 1993
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- 21 February 2011, 347
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- 1993
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a-GaN thin films have been grown on (0001) sapphire by a plasma-enhanced atomic layer epitaxy (PEALE) technique using a GaN buffer layer grown at lower temperatures. Both single crystal and polycrystal thin films have been obtained depending on the growth conditions, particularly, oxygen contamination of the plasma source and the substrate temperature. The orientation relationship between the single crystal film and the substrate is [0001]GaN//[0001]Al2O3, [l100]GaN//[1210]Al2O3 and [2110]GaN//[l100]Al2O3. The polycrystalline film has the c-axis perpendicular to the substrate and contains the same orientation found in the single crystal film. However, two additional orientations have been found that are rotated approximately ±19° from the single crystal orientation. The defect structures at the film/substrate interface were investigated by various X-ray methods such as rocking curves and phi scans, along with plane-view and cross sectional TEM. Possible growth mechanisms of both the single crystal and polycrystalline films will be discussed.
X-Ray Determination of Strain Distribution in Inconel Alloy 600 C-Ring
- C. F. Lo, H. Kamide, G. Feng, W. E. Mayo, S. Weissmann
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- MRS Online Proceedings Library Archive / Volume 142 / 1988
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- 21 February 2011, 53
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- 1988
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An Inconel Alloy 600 C-ring was subjected to various strain levels and the deformation process was monitored by a Computer Aided Rocking Curve Analyzer (CARCA). A large grain population was sampled, and the calibration curve of average rocking curve halfwidth of the individual grains relating to the nominal strain was established. The strain distribution as a function of the angular position along the peripheral surface layer and layers at different depth distance was obtained. Up to C-ring closure at the nominal strain of 3.3% at the apex, the induced plastic strains were confined to a surface layer of 30–40 gm in depth.The largest strain and strain gradients below the surface occurred at the apex and near apex region. The extent and the spread of microdeformation inhomogeneity increased with applied strain. At ring closure some grains exhibited large plastic strains while others exhibited only small plastic strains or were not affected by the deformation process at all. These experimental results were not in agreement with the current theoretical understanding of the deformation of C-ring since these theories did not take shape changes into account. When such changes were included, good agreement on the angular strain dependence for the apex and near apex region were achieved between experiment and theory. It was concluded that the CARCA X-ray method can be a useful research tool in aiding and guiding mathematical modeling of non-linear inelastic behavior of solids by disclosing important microstructural and micromechanical aspects.
Rapid Non-Destructive X-Ray Characterization of Solid Fuels/Propellants
- T. S. Ananthanarayanan, W. E. Mayo, R. G. Rosemeier, R. S. Miller
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- Advances in X-ray Analysis / Volume 30 / 1986
- Published online by Cambridge University Press:
- 06 March 2019, pp. 357-365
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- 1986
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Numerous studies have been conducted into the microstructural origin of the instability and unpredictability of various energetic materials. Some of these materials are RDX/HMX, Ammonium Perchlorate, Aluminum, etc. Many techniques both destructive and non-destructive have so far been utilized in an attempt to quatify the energetic properties of their composites. These composites may contain one or more energetic constituents in an elastomeric binder. Non-destructive X-ray characterization techniques have been successfully employed to measure several microstructural parameters. Previous studies have shown considerable differences among various production grade RDX. These studies reveal marked differences in the amounts of residual elastic strain and the distribution of dislocations (residual plastic strain) in the constituent RDX phase.
The focus of this study is to develop a technique for quantitative constituent phase analysis of solid-propellant (fuel) composites using conventional diffractometry. The use of a Curved Position Sensitive Detector (CPSD) greatly enhances the technique and allows real time applications in production environments. Through the use of computer based Systems and "user friendly" software the required Operator, skill and training have been considerably reduced. The CPSD System has been successfully used to quantify constituent phases (peak heights) and the amounts of residual elastic strain (peak shifts) in these molecular crystal powder mixtures.
It is envisioned that rapid, automated, non-destructive X-ray characterization techniques will greatly facilitate production based propellant quality control. A thorough understanding of the relationship between the energetics and microstructural parameters can also he obtained.
Digital X-Ray Rocking Curve Topography
- T. S. Ananthanarayanan, R. G. Rosemeier, W. E. Mayo, J. H. Dinan
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- Journal:
- MRS Online Proceedings Library Archive / Volume 82 / 1986
- Published online by Cambridge University Press:
- 26 February 2011, 227
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- 1986
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There is a considerable body of work available illustrating the significance of X-ray rocking curve measurements in micro-electronic applications. For the first time a high resolution (100-150µm) 2-dimensional technique called DARC (Digital Autcmated Rocking Curve) topography has been implemented. This method is an enhancement of the conventional double crystal diffractometer using a real time 2-dimensional X-ray detector.
Several materials have been successfully examined using DARC topography. Same of these include: Si, GaAs, AlGaAs, InGaAs, HgMnTe, Al, Inconel, steels, etc. By choosing the appropriate Bragg reflection multi-layered micro-electronic structures have been analyzed nondestructively. Several epitaxial films, including HgCdTe and ZnCdTe, grown by molecular beam epitaxy, have also been characterized using iARC topography. The rocking curve half width maps can be translated to dislocation density maps with relative ease. This technique also allows the deconvolution of the micro-plastic lattice strain ccaponent from the total strain tensor.
Subsurface Micro-Lattice Strain Mapping
- T. S. Ananthanarayanan, R. G. Rosemeier, W. E. Mayo, P. Becla
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- MRS Online Proceedings Library Archive / Volume 90 / 1986
- Published online by Cambridge University Press:
- 25 February 2011, 209
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- 1986
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Defect morphology and distribution up to depths of 20um have been shown to be critical to device performance in micro-electronic applications. A unique and novel x-ray diffraction method called DARC (Digital Automated Rocking Curve) topography has been effectively utilized to map crystalline micro-lattice strains in various substrates and epitaxial films. The spatial resolution of this technique is in the the order of 100um and the analysis time for a 2cm2 area is about 10 secs. DARC topography incorporates state-ofthe- art 1-dimensional and 2-dimensional X-ray detectors to modify a conventional Double Crystal Diffractometer to obtain color x-ray rocking curve topographs.
This technique, being non-destructive and non-intrusive in nature, is an invaluable tool in materials’ quality control for IR detector fabrication. The DARC topographs clearly delineate areas of microplastic strain inhomogeniety. Materials analyzed using this technique include HgMnTe, HgCdTe, BaF2, PbSe, PbS both substrates and epitaxial films. By varying the incident x-ray beam wavelength the depth of penetration can be adjusted from a 1–2 micron up to 15–20um. This can easily be achieved in a synchrotron.