Sample records for study cgsc analysis

  1. The application of computers to learning in the Command and General Staff College (CGSC): A front end analysis study: CGSC analysis, Task A

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thorn, C.T.

    1988-01-01

    The US Army Command and General Staff College (CGSC) is organized in five schools, one of which, Command and General Staff School (CGSS), is not formally established. These schools provide instruction to officers, noncommissioned officers, and civilians through 4 primary courses and approximately 20 shorter courses. The primary courses are CAS/sup 3/ (Combined Arms and Services Staff School) Phase I Nonresident Course, CAS/sup 3/ Phase II Resident Course, CGSOC (Command and General Staff Officers Course), and SAMS (School of Advanced Military Studies). The shorter courses are primarily provided through SPD (School of Professional Development). Task A analyzed the curricula ofmore » the primary courses in terms of organization and cognitive level with the goal of providing the project team sufficient understanding of the College to seriously address the issue of the application of computers to learning in Task G.« less

  2. Army Reserve Instructors' Perceptions regarding the Effectiveness of the Experiential Learning Model in Teaching Mid-Level Army Reserve Officers

    ERIC Educational Resources Information Center

    Meyer, Robert S.

    2010-01-01

    The Command and General Staff College (CGSC) at Ft. Leavenworth is a fully accredited graduate school. The primary professional development program at CGSC has been for mid-level officers. This program is referred to as ILE (Intermediate Level Education) and is taught in small cohort groups of 12 to 18 students. CGSC has embraced the principles of…

  3. CGSC: Developing Leaders to Adapt and Dominate for the Army of Today and Tomorrow

    DTIC Science & Technology

    2012-10-01

    educational institutions, we occasionally have students who cross an ethi- cal line in their academic studies and are guilty of plagiarism . This is dealt...Lieutenant Colonel James B. Martin is the associate dean of academics and quality assurance, CGSC. He received a B.A. from the University of Kentucky...of international military students studying at Fort Leavenworth. With a total student popula- tion of 1,391 in academic year 2012, 115 were

  4. Master of Military Art and Science (MMAS) Research and Thesis.

    ERIC Educational Resources Information Center

    Army Command and General Staff Coll., Fort Leavenworth, KS.

    This document describes the requirements for the degree of Master of Military Art and Science (MMAS) at the United States Army Command and General Staff College (CGSC), Fort Leavenworth, Kansas. Chapter one outlines program requirements for the MMAS, discusses the place of research at CGSC, describes research requirements for the MMAS, and…

  5. Application of the Soviet Theory of Deep Operation during the 1939 Soviet-Japanese Military Conflict in Mongolia

    DTIC Science & Technology

    2010-06-11

    And the Red Army’s Road To Operational Art 1918-1936,” http://cgsc.leavenworth.army.mil/carl/resources/ biblio /interwar.asp (accessed 25 December...cgsc.leavenworth.army.mil/carl/ resources/ biblio /interwar.asp (accessed 25 December 2009). 20 of military-technical superiority. He understood...resources/ biblio /interwar.asp (accessed 25 December 2009). Military-Topographical Directorate of the General Staff of the USSR. Maps from the

  6. Professors in the Trenches: Deployed Soldiers and Social Science Academics

    DTIC Science & Technology

    2009-01-01

    CGSC Experiential Learning Model, or ELM . The ELM serves as the methodology for both lesson plan design at the Command and General Staff College and as...the experiential learning model ( ELM ) than the U.S. contractors – the ELM methodology, by design, addresses all four learning style preferences. The...Since the CGSC team used the experiential learning model as the way to teach, they modeled the ELM as they taught all their classes. After the first

  7. A Means Towards Understanding: Reconnaissance and the Practice of Operational Art

    DTIC Science & Technology

    2011-12-01

    Soviet Military Operational Art: In Pursuit of Deep Battle (London: Routledge, 1991), 256-257. 24Matthew K . Green, “Operational Reconnaissance: The...1946), 20-21, app. 3, 4, 5, http://www.cgsc.edu/carl/ eto /eto.asp (accessed 29 August 2011). 103James A. Huston, “Tactical Use of Air Power in World War...Nauheim, GE, 1945-1946), 9-11, http://www.cgsc.edu/carl/ eto /eto.asp (accessed 29 August 2011). 104Stephen E. Ambrose, D-Day June 6, 1944: The

  8. Doctrinal Imbalance: A Study of Swedish Army Doctrine

    DTIC Science & Technology

    2014-06-13

    the Swedish National Defense College (SNDC), both to provide vital source material and also to assure me that the study is relevant and had a valid......interpretation of the simulation data. Furthermore, a CGSC tactics instructor, Mr. Steve Scholtz, checked the red and blue battle plans to assure that

  9. A Pending Major Crisis: An Analysis of the Critical Shortage of US Army Officers in Year Groups 1991-1997

    DTIC Science & Technology

    2008-12-12

    Raymond, Jr., PhD _____________________________________, Member COL(R) David Hunter- Chester Accepted this 12th day of December 2008 by...Ph.D., and COL(R) David Hunter- Chester for their insightful and instructive direction; LTG William B. Caldwell IV, Commanding General of the US...J. McCollum and Dr. Constance A. Lowe, CGSC MMAS seminar instructors, LTC Scott Nester PhD Director, Center for Data Analysis & Statistics, West

  10. Full Spectrum Operations: An Analysis of Course Content at the Command and General Staff College

    DTIC Science & Technology

    2008-05-01

    Dynamics of Military Revolutions 1300-2050. Cambridge: Cambridge University Press, 2001. Kolb , David A. Experiential Learning : Experience as the... experiential learning provides latitude for the student or instructor to deviate from the structured lesson plan and pursue alternate avenues to...their contribution. The cognitive learning environment of CGSC is best understood by reviewing the adult learning model and the experiential learning

  11. Life concerns of elderly people living at home determined as by Community General Support Center staff: implications for organizing a more effective integrated community care system. The Kurihara Project.

    PubMed

    Takada, Junko; Meguro, Kenichi; Sato, Yuko; Chiba, Yumiko

    2014-09-01

    In Japan, the integrated community care system aims to enable people to continue to live in their homes. Based on the concept, one of the activities of a Community General Support Center (CGSC) is to provide preventive intervention based on a Community Support Program. Currently, a Basic Checklist (BC) is sent to elderly people to identify persons appropriate for a Secondary Prevention Program. To find people who had not responded to the BC, CGSC staff evaluated the files of 592 subjects who had participated in the Kurihara Project to identify activities they cannot do that they did in the past, decreased activity levels at home, loss of interaction with people other than their family, and the need for medical interventions. This information was classified, when applicable, into the following categories: (A) 'no life concerns'; (B) 'undecided'; and (C) 'life concerns'. The relationships between these classifications and clinical information, certified need for long-term care, and items on the BC were examined. The numbers of subjects in categories A, B, and C were 291, 42, and 186, respectively. Life concerns were related to scores on the Clinical Dementia Rating, global cognitive function, depressive state, and apathy. Most items on the BC were not associated with classification into category C, but ≥25% of the subjects had life concerns related to these items. Assessment of life concerns by the CGSC staff has clinical validity. The results suggest that there are people who do not respond to the checklist or apply for Long-Term Care Insurance, meaning that they 'hide' in the community, probably due to apathy or depressive state. To organize a more effective integrated community care system, the CGSC staff should focus mainly on preventive care. © 2014 The Authors. Psychogeriatrics © 2014 Japanese Psychogeriatric Society.

  12. Mission Command During The Falklands War: Opportunities And Limitations

    DTIC Science & Technology

    2016-05-26

    Monograph by MAJ Brice Roberts United States Army School of Advanced Military Studies United States Army Command and General Staff College Fort...SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) Advanced Military Studies Program CGSC 11. SPONSOR...This study examines the six principles of mission command, as defined by ADP 6-0, as a lens to evaluate operations conducted by the Landing Force

  13. PTSD Type Symptoms and CGSC class 08-01, a Study of Field Grade Officers and Implications for the Future

    DTIC Science & Technology

    2008-06-13

    Psychotherapy- “talk therapy” pioneered by Sigmund Freud . One on one, group, and family psychotherapy are all used in treating PTSD. PTSD- Post Traumatic...It was during WWII and the Korean War that it became known as “Battle Fatigue” or “Combat Exhaustion” (Hyams 2005). Sigmund Freud’s model of...

  14. An Exploration of How U.S. Army Officers Attending the U.S. Army Command and General Staff College Decide Whether or Not to Attend Graduate School: A Qualitative Case Study

    ERIC Educational Resources Information Center

    Vance, Charles David

    2013-01-01

    This qualitative case study explored how U.S. Army Command and General Staff College (CGSC) students decided whether or not to attend graduate school. The focus was on how U.S. Army students made their decision. The purpose of the study was to illuminate the issues related to this decision in adult development, adult learning, career decision…

  15. All Those Who Remained: The American-Led Guerillas in the Philippines, 1942-1945

    DTIC Science & Technology

    2014-12-04

    United States Army School of Advanced Military Studies United States Army Command and General Staff College Fort Leavenworth, Kansas 2014-02...SPONSOR/MONITOR’S ACRONYM(S) Command and General Staff College CGSC 731 McClellan Avenue Fort Leavenworth, KS 66027-1350 11. SPONSOR/MONITOR’S...Luzon through all phases of the campaign. This monograph evaluates the effectiveness of these American-led guerilla groups in supporting the US

  16. The Decision to Accept or Decline Command: An Analysis of Considerations by FY 82 05/06 Selectees and a CGSC Sample

    DTIC Science & Technology

    1982-06-01

    the bills. The days of packing mama and the baby up, picking up vy foc’t locler and moving out are over for us -- and a lot of other Jbrvy fclks in...don’t regret the decision and will stay in command for 18 months without dependants even though my family is terribly depressed and disappointed. "Some...cervical cancer and was operated upon. Indications were that it was successful, but she required follow-up checks every 3 months at Walter Reed Army

  17. 77 FR 17036 - Advisory Committee Meeting Notice

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-23

    ... announces the following committee meeting: Name of Committee: U.S. Army Command & General Staff College Subcommittee. Date: April 23-25, 2012. Place: U.S. Army Command and General Staff College, Ft. Leavenworth, KS... overview of the CGSC, as well as its constituent schools, the Command and General Staff School and the...

  18. Intelligence Architecture, Echelons Corps and Below (ECB): Some Near Term Alternatives

    DTIC Science & Technology

    1991-04-05

    intelligence missions. - Failure to have an annual "MI Table VIII" type evaluation system keeps MI units in the business of supporting other Table...Division) CAC: Combined Arms Center (Ft Leavenworth) CEWI: Combat Electronic Warfare Inteligence C&GSC: Command and General Staff College CI

  19. The Challenge of Adaptation: The US Army in the Aftermath of Conflict, 1953-2000

    DTIC Science & Technology

    2008-03-01

    on U.S. National Security Strategy, 21 June 2001, pp.4-5. Chaired by Senator Carl Levin (D-MI). Retrieved from LexisNexis Congressional Search...and Scott D. Sagan , Moving Targets: Nuclear Strategy and National Security (Princeton: Princeton University Press, 1989). 4. Boyd L. Dastrup, The...KS: Combat Studies Institute, July 1980), available at: http://www. cgsc.army.mil/ carl /resources/csi/heller2/heller2.asp. 13. Condit, HOSD, v.II: The

  20. Virtuous Influence: An Imperative to Solve U.S. Strategic Communication Quandary

    DTIC Science & Technology

    2011-03-24

    and to have strategic implications. One early lesson from the Jasmine Revolution in Tunisia is the devastating consequences one single act may have...professionals, scholars, and students develop divergent views of the very essence of ―strategic communication.‖2 As stated by an U.S. Army CGSC student

  1. How Military Personnel Can Stretch Their Dollars.

    ERIC Educational Resources Information Center

    Forrest, Ernest E., Jr.

    The paper deals with the need for personal finance training in the service. Through the media of a survey conducted at the USAWC and CGSC, it was determined that personal finance training was highly desired by respondents, that the median knowledge level of personal finance subjects was very low, and that most of the respondents could improve…

  2. Military Review Volume 73 April 1993 Number 4

    DTIC Science & Technology

    1993-04-01

    93--4 Brigadier General Wiliam M. Steele CONTENTS De "ut Commanidant, US4CGSC Military Review Staff 2 Going Deep: Division Air Assault Operations...rotary- Schwarzkopf anmong them, consider the ( obra winged warhorses by the dozen, more than a operation and its agyressive, determined exploi- hundred...rowed. But unquestionably, the capability is through three important, sequential steps: de - there to be used. ciding, battlefield preparations and

  3. Integrated Nuclear Considerations: C&GSC Pre-Command Course Instructional Material.

    DTIC Science & Technology

    1980-11-21

    support of TFI-12’s withdrawal to PL BOB, then to countermobiltiy and survival operations in support of BPs on PL BOB with priority to sector of TF1 -12 and...BPs 11 and 12, in order. b. Be prepared to support CATK of TF1 -12 vicinity BREITENBACH. 13. S4: a. Supervise accomplishment of task in 2, above. b

  4. The Civil Side of Irregular Warfare

    DTIC Science & Technology

    2014-05-22

    Burj al -Shimali.52 While Musa al Sadr is not the founder of Hezbollah, his work resulted in the network of connections and the recasting of Shia...Center AMAL afwaj al -muqawama al -lubnaniya (Lebanese Resistance Regiments) = amal (Hope) CA Civil Affairs CAO Civil Affairs Operations CGSC US Army...HAMAS Harakat al -Muqawama al -Islamiyya (the Islamic Resistance Movement) IDF Israel Defense Forces IGO Intergovernmental Organization IW Irregular

  5. The Olive Branch and the Spear: Merging Diplomatic Actions and Special Operations in Conflict Prevention

    DTIC Science & Technology

    2013-06-13

    The survey was reviewed and approved by the CGSC Human Protections Administrator under the number #13-03-055. This survey targeted an audience of ...merging the human resources from both organizations for “high reward low cost” operations. At the operational level, an overall review of the ...indirect approaches, in order to successfully take up the conflict prevention challenge. Assessing the robustness of an

  6. Pakistan Education Systems and the Radical Islamic Jihadist Ideology

    DTIC Science & Technology

    2006-12-15

    leaders; the expulsion of foreign madrassa students; and new registration and financial disclosure requirements on madrassas.”4 The Pakistani...7Hoffman, Inside Terrorism ( New York: Columbia University Press, 1998), 43. 8John Cary, “Components of an Ideology” (CGSC Middle East Strategic...13John L Esposito, Islam: The Straight Path ( New York: Oxford University Press, 1998), 34. 14Rabasa, 8. 15NMSP-WOT, 35. 16Esposito, Islam, 232. 8

  7. Personnel Systems in Europe in Preparation for Operation OVERLORD: How Did They Work?

    DTIC Science & Technology

    2014-05-01

    and processes provided American and Commonwealth nations with the necessary requirements to conduct operations in the ETO . The third section exposed...War Department CARL Combined Arms Research Library CGSC US Army Command and General Staff College EPW Enemy Prisoner of War ETO European Theater...oversight and synchronization of all American and Commonwealth nations operations in the European Theater of Operation ( ETO ).7 From a management of

  8. Evaluation of Data Elements for Training Information Feedback System in Context of Post-CGSC Assignments

    DTIC Science & Technology

    1980-08-01

    Appendix B. 12 ------------- ---. _ _ _ _ ______i_____mi__i_ LEGEND Percent of Time Spend Criticalit Aplicability *** on Job Commnent*** t--etc...Communications Officer G-2 Performs communications-electronics (CE) staff functions 6-3 Directs and controls operations of mobile communications...support unit FORM B Cont’d _ _ _ _ -W -l G-4 Establishes and controls mobile area signal center G-5 Manages communications-electronics facilities and

  9. Evaluation of Injuries among Command and General Staff College Students, Ft. Leavenworth, Kansas

    DTIC Science & Technology

    2015-11-30

    ounces or 2 bottles 7 (4%) 60 ounces or 3 bottles 1 (1%) Table F-3. Dietary Supplement Use, CGSC Initial Survey Respondents (n=185) Question... Supplement /Reason N (%) Dietary Supplements Do not take 133 (58%) Vitamins/ Multivitamins 44 (19%) Performance/muscle enhancement 19 (8%) Healthy joint...15 (7%) Nutrition enhancement 9 (4%) Weight loss 9 (4%) Reasons for Taking Dietary Supplements (among those using supplements (n=96)) Promote

  10. Creating The Pentathlete: Are We Willing to Pay the Price?

    DTIC Science & Technology

    2007-04-11

    derives from Greek words for “five competitions.” The five events were stadion (short foot race), wrestling, the long jump, javelin throw , discus...Center at Fort Benning, Georgia and US Army Majors ( all branches) attending Command and General Staff College (CGSC) and the School of Advanced...such a multi-faceted, multi- skilled, “Jack-of- all -Trades” officer? Finally, this paper concludes with ideas, methods and recommendations at the

  11. Signal Corps and Military Intelligence Officer Perceptions of a Multifunctional Branch Merger

    DTIC Science & Technology

    2015-06-12

    CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Martin, Johnathan P. Major US Army 5d. PROJECT NUMBER 5e. TASK...Commander, Lieutenant General Edward Cardon summed up the issue during a speaking engagement at CGSC stating: “We at the senior leader level are...Intelligence officers. The talent management aspect of the branch structure appears to be the impetus for creating a separate Cyber branch. Cardon said as

  12. Could the United States Army Have a Positive Impact on the Insurgency and Counterdrug Problems in Peru

    DTIC Science & Technology

    1994-06-03

    CGSC, Fort Leavenworth, KS, Dec. 1990 LAS FUERZAS ARMADAS DEL PERU Y LOS DERECHOS HUMANOS EN LA LUCHA CONTRA EL TERRORISMO (Not Dated), A Booklet...op- erations were countered by the DINCOTE (Direccion Nacional Contra el Terrorismo ), a special antiterrorist branch of the national police. They...branches of our Army could contribute to a joint and combined operation in Peru to defeat Shining Path ele - ments. In addition to this, the reader may

  13. On Other War Lessons from Five Decades of RAND Counterinsurgency Research

    DTIC Science & Technology

    2006-01-01

    counterinsurgency (COIN) to the movie Groundhog Day, in which Bill Murray’s character, Phil Connors, is forced to live the same day over and over...and the population, all agree on 4 See Beckett (2005), Sepp (2005), and Lynn (2005) for three recent works that accept this premise. 16 On...www.cgsc.army.mil/carl/resources/csi/content.asp#russ (as of February 14, 2006). 86 On “Other War” Beckett , I. F. W., Insurgency in Iraq: An Historical

  14. Dr. Ivan J. Birrer: Service at the Command and General Staff College, Fort Leavenworth, Kansas, 20 January 1948 to 30 June 1978

    DTIC Science & Technology

    1978-04-21

    sentially a brand new program for 1957-59, I realized that theLp :’as an opportmnity to effect Vhat I had lng thought would be a real improvement in the...War College at Fort Leavenworth Effect of Korean W’ar on CGSC Specialized Instruction Instructor Training Program Design of Bell Hall . 4, -.- 1 A...cover? A: There are a couple of points I did not mention that merit some attention because if their subsequent infiuence _r effect here at the college

  15. Hypothetical Case and Scenario Description for International Transportation of Spent Nuclear Fuel.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Williams, Adam David; Osborn, Douglas; Jones, Katherine A.

    To support more rigorous analysis on global security issues at Sandia National Laboratories (SNL), there is a need to develop realistic data sets without using "real" data or identifying "real" vulnerabilities, hazards or geopolitically embarrassing shortcomings. In response, an interdisciplinary team led by subject matter experts in SNL's Center for Global Security and Cooperation (CGSC) developed a hypothetical case description. This hypothetical case description assigns various attributes related to international SNF transportation that are representative, illustrative and indicative of "real" characteristics of "real" countries. There is no intent to identify any particular country and any similarity with specific real-world eventsmore » is purely coincidental. To support the goal of this report to provide a case description (and set of scenarios of concern) for international SNF transportation inclusive of as much "real-world" complexity as possible -- without crossing over into politically sensitive or classified information -- this SAND report provides a subject matter expert-validated (and detailed) description of both technical and political influences on the international transportation of spent nuclear fuel. [PAGE INTENTIONALLY LEFT BLANK]« less

  16. Guidelines for patient selection and performance of carotid artery stenting.

    PubMed

    2009-12-01

    The endovascular treatment of carotid atherosclerosis with carotid artery stenting (CAS) remains controversial. Carotid endarterectomy (CEA) remains the benchmark in terms of procedural mortality and morbidity. Consensus Australasian guidelines for the safe performance of CAS were developed using the modified Delphi consensus method of iterative consultation. Selection of patients suitable for CAS needs careful consideration of clinical and patho-anatomical criteria. Randomised controlled trials and pooled analyses have demonstrated that CAS is more hazardous than CEA. The CGSC therefore recommends that CAS should not be performed in the majority of patients requiring carotid revascularisation. There is currently no evidence to support CAS as a treatment for asymptomatic carotid stenosis. The use of distal protection devices during CAS remains controversial with increased risk of clinically silent stroke. The knowledge requirements for the safe performance of CAS include an understanding of the evidence base from randomised controlled trials, carotid and aortic arch anatomy and pathology, and recognition and management of periprocedural complications. It is critical that all patients being considered for a carotid intervention have adequate pre-procedural neuroimaging and peri-procedural, independent, neurological assessment. Maintenance of proficiency in CAS requires active involvement in surgical/endovascular audit and continuing medical education programmes. These standards should apply in the public and private health-care settings. These guidelines represent the consensus of an intercollegiate committee in order to direct appropriate patient selection to perform CAS. Advances in endovascular technologies and the results of randomised controlled trials will guide future revisions of this document.

  17. Guidelines for patient selection and performance of carotid artery stenting.

    PubMed

    Bladin, Christopher; Chambers, Brian; New, Gishel; Denton, Michael; Lawrence-Brown, Michael

    2010-06-01

    The endovascular treatment of carotid atherosclerosis with carotid artery stenting (CAS) remains controversial. Carotid endarterectomy remains the benchmark in terms of procedural mortality and morbidity. At present, there are no consensus Australasian guidelines for the safe performance of CAS. We applied a modified Delphi consensus method of iterative consultation between the College representatives on the Carotid Stenting Guidelines Committee (CSGC). Selection of patients suitable for CAS needs careful consideration of clinical and patho-anatomical criteria and cannot be directly extrapolated from clinical indicators for carotid endarterectomy (CEA). Randomized controlled trials (including pooled analyses of results) comparing CAS with CEA for treatment of symptomatic stenosis have demonstrated that CAS is more hazardous than CEA. On current evidence, the CGSC therefore recommends that CAS should not be performed in the majority of patients requiring carotid revascularisation. The evidence for CAS in patients with symptomatic severe carotid stenosis who are considered medically high risk is weak, and there is currently no evidence to support CAS as a treatment for asymptomatic carotid stenosis. The use of distal protection devices during CAS remains controversial with increased risk of clinically silent stroke. The knowledge requirements for the safe performance of CAS include an understanding of the evidence base from randomized controlled trials, carotid and aortic arch anatomy and pathology, clinical stroke syndromes, the differing treatment options for stroke and carotid atherosclerosis, and recognition and management of periprocedural complications. It is critical that all patients being considered for a carotid intervention have adequate pre-procedural neuro-imaging and an independent, standardized neurological assessment before and after the procedure. Maintenance of proficiency in CAS requires active involvement in surgical/endovascular audit and continuing medical education programs. These standards should apply in the public and private health care settings. These guidelines represent the consensus of an inter-collegiate committee in order to direct appropriate patient selection and the range of cognitive and technical requirements to perform CAS. Advances in endovascular technologies and the results of randomized controlled trials will guide future revisions of these guidelines.

  18. Revised stratigraphy and reinterpretation of the Miocene Pohang basinfill, SE Korea: sequence development in response to tectonism and eustasy in a back-arc basin margin

    NASA Astrophysics Data System (ADS)

    Sohn, Y. K.; Rhee, C. W.; Shon, H.

    2001-09-01

    The Miocene Pohang Basin is a pull-apart basin formed along the eastern continental margin of Korea (ECMK) during the back-arc opening of the East Sea (Sea of Japan). The basin is filled by more than 1 km thick, nonmarine to deep-marine strata. These strata show extreme vertical and lateral lithofacies changes and have caused decades-long controversies on their nature and stratigraphy. Previous sedimentological studies suggest that the basinfill was deposited by a series of contemporaneously developed depositional systems, including fan delta, prodelta, slope apron, and basin plain. Detailed mapping and magnetotelluric surveying show, however, that the basinfill is composed of several packages of strata (sequences) that are bounded by distinct and laterally persistent stratigraphic discontinuities (sequence boundaries). This suggests that the depositional systems in the Pohang Basin developed sequentially rather than contemporaneously. Six packages of strata are identified in the basin: a nonmarine to shallow marine (transgressive) sequence (Sequence 1), a Gilbert-type-delta conglomerate (Sequence 2), and alternations of submarine conglomerates and hemipelagic mudstones (Sequences 3-6). The conglomerates and hemipelagic mudstones of the latter four sequences are interpreted to represent lowstand depositional systems (slope apron, submarine fan, and high-gradient delta) and condensed intervals, respectively. Compilation of geochronologic, paleomagnetic, and biostratigraphic data suggests that Sequence 1 formed during the gradual subsidence of the ECMK prior to 17 Ma, whereas Sequence 2 formed in response to abrupt downfaulting of the Pohang Basin at about 17 Ma. Both sequences are interpreted to have developed in response to the early Miocene back-arc-opening tectonism of the East Sea. On the other hand, Sequences 3-6 formed between 17 and about 10.5 Ma. The Pohang Basin was subject to only minor tectonism during this period and could record global sea-level fluctuations. We suggest that the four alternations of conglomerates (lowstand systems) and hemipelagic mudstones (condensed intervals) resulted most probably from the 3rd-order glacioeustatic cycles during the middle Miocene. This finding implies that the signatures of global sea-level fluctuations can be deciphered from a tectonically active sedimentary basin if the timing of regional tectonic development is well constrained, and the global sea-level chart of Haq et al. ( Haq, B.W., Hardenbol, J., Vail, P.R., 1987, Chronology of fluctuating sea levels since the Triassic. Science 235, 1156-1167; Haq, B.U., Hardenbol, J., Vail, P.R., 1988. Mesozoic and Cenozoic chronostratigraphy and eustatic cycles. In: Wilgus, C.K., Hastings, B.S., Posamentier, H., Van Wagoner, J., Ross, C.A., Kendall, C.G.S.C. (Eds.), Sea-Level Changes: an Integrated Approach: Soc. Econ. Paleont. Mineral. Spec. Publ. 42, pp. 71-108) may serve as a guide to basinfill interpretation even in tectonically active sedimentary basins.

  19. 34 CFR 477.1 - What is the State Program Analysis Assistance and Policy Studies Program?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ANALYSIS ASSISTANCE AND POLICY STUDIES PROGRAM General § 477.1 What is the State Program Analysis Assistance and Policy Studies Program? The State Program Analysis Assistance and Policy Studies Program... 34 Education 3 2011-07-01 2011-07-01 false What is the State Program Analysis Assistance and...

  20. 34 CFR 477.1 - What is the State Program Analysis Assistance and Policy Studies Program?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ANALYSIS ASSISTANCE AND POLICY STUDIES PROGRAM General § 477.1 What is the State Program Analysis Assistance and Policy Studies Program? The State Program Analysis Assistance and Policy Studies Program... 34 Education 3 2010-07-01 2010-07-01 false What is the State Program Analysis Assistance and...

  1. Multivariate Methods for Meta-Analysis of Genetic Association Studies.

    PubMed

    Dimou, Niki L; Pantavou, Katerina G; Braliou, Georgia G; Bagos, Pantelis G

    2018-01-01

    Multivariate meta-analysis of genetic association studies and genome-wide association studies has received a remarkable attention as it improves the precision of the analysis. Here, we review, summarize and present in a unified framework methods for multivariate meta-analysis of genetic association studies and genome-wide association studies. Starting with the statistical methods used for robust analysis and genetic model selection, we present in brief univariate methods for meta-analysis and we then scrutinize multivariate methodologies. Multivariate models of meta-analysis for a single gene-disease association studies, including models for haplotype association studies, multiple linked polymorphisms and multiple outcomes are discussed. The popular Mendelian randomization approach and special cases of meta-analysis addressing issues such as the assumption of the mode of inheritance, deviation from Hardy-Weinberg Equilibrium and gene-environment interactions are also presented. All available methods are enriched with practical applications and methodologies that could be developed in the future are discussed. Links for all available software implementing multivariate meta-analysis methods are also provided.

  2. Research relative to atmosphere physics and spacecraft applications studies

    NASA Technical Reports Server (NTRS)

    Greenwood, Stuart W.

    1987-01-01

    Progress is reported in several areas of research. Brief descriptions are given in each of the following areas: Spacelab data analysis; San Marco activity; Molecular physics; Stellar energy analysis; Troposphere data analysis; Voyager encounter analysis; Laser activity; Gravity wave study; Venus studies; and Shuttle environmental studies.

  3. Secondary data analysis of large data sets in urology: successes and errors to avoid.

    PubMed

    Schlomer, Bruce J; Copp, Hillary L

    2014-03-01

    Secondary data analysis is the use of data collected for research by someone other than the investigator. In the last several years there has been a dramatic increase in the number of these studies being published in urological journals and presented at urological meetings, especially involving secondary data analysis of large administrative data sets. Along with this expansion, skepticism for secondary data analysis studies has increased for many urologists. In this narrative review we discuss the types of large data sets that are commonly used for secondary data analysis in urology, and discuss the advantages and disadvantages of secondary data analysis. A literature search was performed to identify urological secondary data analysis studies published since 2008 using commonly used large data sets, and examples of high quality studies published in high impact journals are given. We outline an approach for performing a successful hypothesis or goal driven secondary data analysis study and highlight common errors to avoid. More than 350 secondary data analysis studies using large data sets have been published on urological topics since 2008 with likely many more studies presented at meetings but never published. Nonhypothesis or goal driven studies have likely constituted some of these studies and have probably contributed to the increased skepticism of this type of research. However, many high quality, hypothesis driven studies addressing research questions that would have been difficult to conduct with other methods have been performed in the last few years. Secondary data analysis is a powerful tool that can address questions which could not be adequately studied by another method. Knowledge of the limitations of secondary data analysis and of the data sets used is critical for a successful study. There are also important errors to avoid when planning and performing a secondary data analysis study. Investigators and the urological community need to strive to use secondary data analysis of large data sets appropriately to produce high quality studies that hopefully lead to improved patient outcomes. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  4. Using multipliers analysis in order to get another perspective related to the role of ICT sectors in national economy of Indonesia: 1990-2005

    NASA Astrophysics Data System (ADS)

    Zuhdi, Ubaidillah

    2014-04-01

    The purpose of this study is to get another perspective related to the role of Information and Communication Technology (ICT) sectors in national economy of Indonesia. The period of analysis of this study is 1990-2005. This study employs Input-Output (IO) analysis as a tool of analysis. More specifically, this study uses simple output multipliers method in order to achieve the purpose. Comparison with previous study is conducted in order to get the objective of this study. Previous study, using Structural Decomposition Analysis (SDA), showed that ICT sectors did not have an important role in Indonesian national economy in above period. The similar results also appear in this study. In other words, from this study, another perspective related to the role of these sectors in Indonesian national economy in analysis period is not found.

  5. Qualitative case study data analysis: an example from practice.

    PubMed

    Houghton, Catherine; Murphy, Kathy; Shaw, David; Casey, Dympna

    2015-05-01

    To illustrate an approach to data analysis in qualitative case study methodology. There is often little detail in case study research about how data were analysed. However, it is important that comprehensive analysis procedures are used because there are often large sets of data from multiple sources of evidence. Furthermore, the ability to describe in detail how the analysis was conducted ensures rigour in reporting qualitative research. The research example used is a multiple case study that explored the role of the clinical skills laboratory in preparing students for the real world of practice. Data analysis was conducted using a framework guided by the four stages of analysis outlined by Morse ( 1994 ): comprehending, synthesising, theorising and recontextualising. The specific strategies for analysis in these stages centred on the work of Miles and Huberman ( 1994 ), which has been successfully used in case study research. The data were managed using NVivo software. Literature examining qualitative data analysis was reviewed and strategies illustrated by the case study example provided. Discussion Each stage of the analysis framework is described with illustration from the research example for the purpose of highlighting the benefits of a systematic approach to handling large data sets from multiple sources. By providing an example of how each stage of the analysis was conducted, it is hoped that researchers will be able to consider the benefits of such an approach to their own case study analysis. This paper illustrates specific strategies that can be employed when conducting data analysis in case study research and other qualitative research designs.

  6. Coffee consumption is not associated with ovarian cancer risk: a dose-response meta-analysis of prospective cohort studies.

    PubMed

    Berretta, Massimiliano; Micek, Agnieszka; Lafranconi, Alessandra; Rossetti, Sabrina; Di Francia, Raffaele; De Paoli, Paolo; Rossi, Paola; Facchini, Gaetano

    2018-04-17

    Coffee consumption has been associated with numerous cancers, but evidence on ovarian cancer risk is controversial. Therefore, we performed a meta-analysis on prospective cohort studies in order to review the evidence on coffee consumption and risk of ovarian cancer. Studies were identified through searching the PubMed and MEDLINE databases up to March 2017. Risk estimates were retrieved from the studies, and dose-response analysis was modelled by using restricted cubic splines. Additionally, a stratified analysis by menopausal status was performed. A total of 8 studies were eligible for the dose-response meta-analysis. Studies included in the analysis comprised 787,076 participants and 3,541 ovarian cancer cases. The results showed that coffee intake was not associated with ovarian cancer risk (RR = 1.06, 95% CI: 0.89, 1.26). Stratified and subgroup analysis showed consisted results. This comprehensive meta-analysis did not find evidence of an association between the consumption of coffee and risk of ovarian cancer.

  7. Systematic Review and Meta-Analysis of Studies Evaluating Diagnostic Test Accuracy: A Practical Review for Clinical Researchers-Part II. Statistical Methods of Meta-Analysis

    PubMed Central

    Lee, Juneyoung; Kim, Kyung Won; Choi, Sang Hyun; Huh, Jimi

    2015-01-01

    Meta-analysis of diagnostic test accuracy studies differs from the usual meta-analysis of therapeutic/interventional studies in that, it is required to simultaneously analyze a pair of two outcome measures such as sensitivity and specificity, instead of a single outcome. Since sensitivity and specificity are generally inversely correlated and could be affected by a threshold effect, more sophisticated statistical methods are required for the meta-analysis of diagnostic test accuracy. Hierarchical models including the bivariate model and the hierarchical summary receiver operating characteristic model are increasingly being accepted as standard methods for meta-analysis of diagnostic test accuracy studies. We provide a conceptual review of statistical methods currently used and recommended for meta-analysis of diagnostic test accuracy studies. This article could serve as a methodological reference for those who perform systematic review and meta-analysis of diagnostic test accuracy studies. PMID:26576107

  8. Research into Practice: The Influence of Discourse Studies on Language Descriptions and Task Design in Published ELT Materials

    ERIC Educational Resources Information Center

    Gilmore, Alex

    2015-01-01

    Discourse studies is a vast, multidisciplinary, and rapidly expanding area of research, embracing a range of approaches including discourse analysis, corpus analysis, conversation analysis, interactional sociolinguistics, critical discourse analysis, genre analysis and multimodal discourse analysis. Each approach offers its own unique perspective…

  9. General Framework for Meta-analysis of Rare Variants in Sequencing Association Studies

    PubMed Central

    Lee, Seunggeun; Teslovich, Tanya M.; Boehnke, Michael; Lin, Xihong

    2013-01-01

    We propose a general statistical framework for meta-analysis of gene- or region-based multimarker rare variant association tests in sequencing association studies. In genome-wide association studies, single-marker meta-analysis has been widely used to increase statistical power by combining results via regression coefficients and standard errors from different studies. In analysis of rare variants in sequencing studies, region-based multimarker tests are often used to increase power. We propose meta-analysis methods for commonly used gene- or region-based rare variants tests, such as burden tests and variance component tests. Because estimation of regression coefficients of individual rare variants is often unstable or not feasible, the proposed method avoids this difficulty by calculating score statistics instead that only require fitting the null model for each study and then aggregating these score statistics across studies. Our proposed meta-analysis rare variant association tests are conducted based on study-specific summary statistics, specifically score statistics for each variant and between-variant covariance-type (linkage disequilibrium) relationship statistics for each gene or region. The proposed methods are able to incorporate different levels of heterogeneity of genetic effects across studies and are applicable to meta-analysis of multiple ancestry groups. We show that the proposed methods are essentially as powerful as joint analysis by directly pooling individual level genotype data. We conduct extensive simulations to evaluate the performance of our methods by varying levels of heterogeneity across studies, and we apply the proposed methods to meta-analysis of rare variant effects in a multicohort study of the genetics of blood lipid levels. PMID:23768515

  10. GWAMA: software for genome-wide association meta-analysis.

    PubMed

    Mägi, Reedik; Morris, Andrew P

    2010-05-28

    Despite the recent success of genome-wide association studies in identifying novel loci contributing effects to complex human traits, such as type 2 diabetes and obesity, much of the genetic component of variation in these phenotypes remains unexplained. One way to improving power to detect further novel loci is through meta-analysis of studies from the same population, increasing the sample size over any individual study. Although statistical software analysis packages incorporate routines for meta-analysis, they are ill equipped to meet the challenges of the scale and complexity of data generated in genome-wide association studies. We have developed flexible, open-source software for the meta-analysis of genome-wide association studies. The software incorporates a variety of error trapping facilities, and provides a range of meta-analysis summary statistics. The software is distributed with scripts that allow simple formatting of files containing the results of each association study and generate graphical summaries of genome-wide meta-analysis results. The GWAMA (Genome-Wide Association Meta-Analysis) software has been developed to perform meta-analysis of summary statistics generated from genome-wide association studies of dichotomous phenotypes or quantitative traits. Software with source files, documentation and example data files are freely available online at http://www.well.ox.ac.uk/GWAMA.

  11. Orbit Transfer Vehicle (OTV) engine, phase A study. Volume 2: Study

    NASA Technical Reports Server (NTRS)

    Mellish, J. A.

    1979-01-01

    The hydrogen oxygen engine used in the orbiter transfer vehicle is described. The engine design is analyzed and minimum engine performance and man rating requirements are discussed. Reliability and safety analysis test results are presented and payload, risk and cost, and engine installation parameters are defined. Engine tests were performed including performance analysis, structural analysis, thermal analysis, turbomachinery analysis, controls analysis, and cycle analysis.

  12. How Many Studies Do You Need? A Primer on Statistical Power for Meta-Analysis

    ERIC Educational Resources Information Center

    Valentine, Jeffrey C.; Pigott, Therese D.; Rothstein, Hannah R.

    2010-01-01

    In this article, the authors outline methods for using fixed and random effects power analysis in the context of meta-analysis. Like statistical power analysis for primary studies, power analysis for meta-analysis can be done either prospectively or retrospectively and requires assumptions about parameters that are unknown. The authors provide…

  13. The Utility of Template Analysis in Qualitative Psychology Research.

    PubMed

    Brooks, Joanna; McCluskey, Serena; Turley, Emma; King, Nigel

    2015-04-03

    Thematic analysis is widely used in qualitative psychology research, and in this article, we present a particular style of thematic analysis known as Template Analysis. We outline the technique and consider its epistemological position, then describe three case studies of research projects which employed Template Analysis to illustrate the diverse ways it can be used. Our first case study illustrates how the technique was employed in data analysis undertaken by a team of researchers in a large-scale qualitative research project. Our second example demonstrates how a qualitative study that set out to build on mainstream theory made use of the a priori themes (themes determined in advance of coding) permitted in Template Analysis. Our final case study shows how Template Analysis can be used from an interpretative phenomenological stance. We highlight the distinctive features of this style of thematic analysis, discuss the kind of research where it may be particularly appropriate, and consider possible limitations of the technique. We conclude that Template Analysis is a flexible form of thematic analysis with real utility in qualitative psychology research.

  14. A Review of Strategic Mobility Models and Analysis

    DTIC Science & Technology

    1991-01-01

    Logistics Directorate of the Joint Staff, (JS-J-4) specifically by the Studies , Concepts, and Analysis Division (SCAD), which conducts long-range...their analysis objec- tives. This study was designed to assist the Logistics Directorate of the Joint Staff (JS/J-4) to understand and improve the...This study concentrated on resource planning, which is the type of planning performed by the Logistics Directorate’s Studies , Concepts, and Analysis

  15. A comparison of two follow-up analyses after multiple analysis of variance, analysis of variance, and descriptive discriminant analysis: A case study of the program effects on education-abroad programs

    Treesearch

    Alvin H. Yu; Garry Chick

    2010-01-01

    This study compared the utility of two different post-hoc tests after detecting significant differences within factors on multiple dependent variables using multivariate analysis of variance (MANOVA). We compared the univariate F test (the Scheffé method) to descriptive discriminant analysis (DDA) using an educational-tour survey of university study-...

  16. 78 FR 8150 - Proposed Information Collection Activity; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-05

    ... three components: the ``Design and Implementation Study,'' the ``Performance Analysis Study,'' and the...- Component Evaluation--Data Collection Related to the Performance Analysis Study and the Impact and the In-depth Implementation Study. OMB No.: 0970-0398 Description: The Office of Data Analysis, Research, and...

  17. The Economic Value of Mangroves: A Meta-Analysis

    Treesearch

    Marwa Salem; D. Evan Mercer

    2012-01-01

    This paper presents a synthesis of the mangrove ecosystem valuation literature through a meta-regression analysis. The main contribution of this study is that it is the first meta-analysis focusing solely on mangrove forests, whereas previous studies have included different types of wetlands. The number of studies included in the regression analysis is 44 for a total...

  18. Integration of Research Studies: Meta-Analysis of Research. Methods of Integrative Analysis; Final Report.

    ERIC Educational Resources Information Center

    Glass, Gene V.; And Others

    Integrative analysis, or what is coming to be known as meta-analysis, is the integration of the findings of many empirical research studies of a topic. Meta-analysis differs from traditional narrative forms of research reviewing in that it is more quantitative and statistical. Thus, the methods of meta-analysis are merely statistical methods,…

  19. Tissue Non-Specific Genes and Pathways Associated with Diabetes: An Expression Meta-Analysis.

    PubMed

    Mei, Hao; Li, Lianna; Liu, Shijian; Jiang, Fan; Griswold, Michael; Mosley, Thomas

    2017-01-21

    We performed expression studies to identify tissue non-specific genes and pathways of diabetes by meta-analysis. We searched curated datasets of the Gene Expression Omnibus (GEO) database and identified 13 and five expression studies of diabetes and insulin responses at various tissues, respectively. We tested differential gene expression by empirical Bayes-based linear method and investigated gene set expression association by knowledge-based enrichment analysis. Meta-analysis by different methods was applied to identify tissue non-specific genes and gene sets. We also proposed pathway mapping analysis to infer functions of the identified gene sets, and correlation and independent analysis to evaluate expression association profile of genes and gene sets between studies and tissues. Our analysis showed that PGRMC1 and HADH genes were significant over diabetes studies, while IRS1 and MPST genes were significant over insulin response studies, and joint analysis showed that HADH and MPST genes were significant over all combined data sets. The pathway analysis identified six significant gene sets over all studies. The KEGG pathway mapping indicated that the significant gene sets are related to diabetes pathogenesis. The results also presented that 12.8% and 59.0% pairwise studies had significantly correlated expression association for genes and gene sets, respectively; moreover, 12.8% pairwise studies had independent expression association for genes, but no studies were observed significantly different for expression association of gene sets. Our analysis indicated that there are both tissue specific and non-specific genes and pathways associated with diabetes pathogenesis. Compared to the gene expression, pathway association tends to be tissue non-specific, and a common pathway influencing diabetes development is activated through different genes at different tissues.

  20. [Analysis of researchers' implication in a research-intervention in the Stork Network: a tool for institutional analysis].

    PubMed

    Fortuna, Cinira Magali; Mesquita, Luana Pinho de; Matumoto, Silvia; Monceau, Gilles

    2016-09-19

    This qualitative study is based on institutional analysis as the methodological theoretical reference with the objective of analyzing researchers' implication during a research-intervention and the interferences caused by this analysis. The study involved researchers from courses in medicine, nursing, and dentistry at two universities and workers from a Regional Health Department in follow-up on the implementation of the Stork Network in São Paulo State, Brazil. The researchers worked together in the intervention and in analysis workshops, supported by an external institutional analysis. Two institutions stood out in the analysis: the research, established mainly with characteristics of neutrality, and management, with Taylorist characteristics. Differences between researchers and difficulties in identifying actions proper to network management and research were some of the interferences that were identified. The study concludes that implication analysis is a powerful tool for such studies.

  1. How to Perform a Systematic Review and Meta-analysis of Diagnostic Imaging Studies.

    PubMed

    Cronin, Paul; Kelly, Aine Marie; Altaee, Duaa; Foerster, Bradley; Petrou, Myria; Dwamena, Ben A

    2018-05-01

    A systematic review is a comprehensive search, critical evaluation, and synthesis of all the relevant studies on a specific (clinical) topic that can be applied to the evaluation of diagnostic and screening imaging studies. It can be a qualitative or a quantitative (meta-analysis) review of available literature. A meta-analysis uses statistical methods to combine and summarize the results of several studies. In this review, a 12-step approach to performing a systematic review (and meta-analysis) is outlined under the four domains: (1) Problem Formulation and Data Acquisition, (2) Quality Appraisal of Eligible Studies, (3) Statistical Analysis of Quantitative Data, and (4) Clinical Interpretation of the Evidence. This review is specifically geared toward the performance of a systematic review and meta-analysis of diagnostic test accuracy (imaging) studies. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  2. MetaGenyo: a web tool for meta-analysis of genetic association studies.

    PubMed

    Martorell-Marugan, Jordi; Toro-Dominguez, Daniel; Alarcon-Riquelme, Marta E; Carmona-Saez, Pedro

    2017-12-16

    Genetic association studies (GAS) aims to evaluate the association between genetic variants and phenotypes. In the last few years, the number of this type of study has increased exponentially, but the results are not always reproducible due to experimental designs, low sample sizes and other methodological errors. In this field, meta-analysis techniques are becoming very popular tools to combine results across studies to increase statistical power and to resolve discrepancies in genetic association studies. A meta-analysis summarizes research findings, increases statistical power and enables the identification of genuine associations between genotypes and phenotypes. Meta-analysis techniques are increasingly used in GAS, but it is also increasing the amount of published meta-analysis containing different errors. Although there are several software packages that implement meta-analysis, none of them are specifically designed for genetic association studies and in most cases their use requires advanced programming or scripting expertise. We have developed MetaGenyo, a web tool for meta-analysis in GAS. MetaGenyo implements a complete and comprehensive workflow that can be executed in an easy-to-use environment without programming knowledge. MetaGenyo has been developed to guide users through the main steps of a GAS meta-analysis, covering Hardy-Weinberg test, statistical association for different genetic models, analysis of heterogeneity, testing for publication bias, subgroup analysis and robustness testing of the results. MetaGenyo is a useful tool to conduct comprehensive genetic association meta-analysis. The application is freely available at http://bioinfo.genyo.es/metagenyo/ .

  3. PubMed Central

    Turchetti, G.; Bellelli, S.; Palla, I.; Forli, F.

    2011-01-01

    SUMMARY The aim of the study consists in a systematic review concerning the economic evaluation of cochlear implant (CI) in children by searching the main international clinical and economic electronic databases. All primary studies published in English from January 2000 to May 2010 were included. The types of studies selected concerned partial economic evaluation, including direct and indirect costs of cochlear implantation; complete economic evaluation, including minimization of costs, cost-effectiveness analysis (CEA), cost-utility analysis (CUA) and cost-benefit analysis (CBA) performed through observational and experimental studies. A total of 68 articles were obtained from the database research. Of these, 54 did not meet the inclusion criteria and were eliminated. After reading the abstracts of the 14 articles selected, 11 were considered eligible. The articles were then read in full text. Furthermore, 5 articles identified by bibliography research were added manually. After reading 16 of the selected articles, 9 were included in the review. With regard to the studies included, countries examined, objectives, study design, methodology, prospect of analysis adopted, temporal horizon, the cost categories analyzed strongly differ from one study to another. Cost analysis, cost-effectiveness analysis and an analysis of educational costs associated with cochlear implants were performed. Regarding the cost analysis, only two articles reported both direct cost and indirect costs. The direct cost ranged between € 39,507 and € 68,235 (2011 values). The studies related to cost-effectiveness analysis were not easily comparable: one study reported a cost per QALY ranging between $ 5197 and $ 9209; another referred a cost of $ 2154 for QALY if benefits were not discounted, and $ 16,546 if discounted. Educational costs are significant, and increase with the level of hearing loss and type of school attended. This systematic review shows that the healthcare costs are high, but savings in terms of indirect and quality of life costs are also significant. Cochlear implantation in a paediatric age is cost-effective. The exiguity and heterogeneity of studies did not allow detailed comparative analysis of the studies included in the review. PMID:22287822

  4. Trends in Educational Research: A Content Analysis of the Studies Published in "International Journal of Instruction"

    ERIC Educational Resources Information Center

    Egmir, Eray; Erdem, Cahit; Koçyigit, Mehmet

    2017-01-01

    The aim of this study is to analyse the studies published in "International Journal of Instruction" ["IJI"] in the last ten years. This study is a qualitative, descriptive literature review study. The data was collected through document analysis, coded using constant comparison and analysed using content analysis. Frequencies…

  5. An Analysis Of The Gps R and D Program As A Case Study Illustrating Dod R and D And Its Associated Successes To Justify The Continued Investments Into And Sustainment Of Dod R and D Budgets

    DTIC Science & Technology

    2016-09-01

    Global Positioning System (GPS). • DOD R&D budget analysis • GPS case study analysis These research areas will support the thesis on the defense... CASE STUDY ANALYSIS As successful as GPS has been on both the battlefield and in worldwide civilian life, the end state wasn’t realized when the...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA JOINT APPLIED PROJECT AN ANALYSIS OF THE GPS R&D PROGRAM AS A CASE STUDY

  6. The Empirical Review of Meta-Analysis Published in Korea

    ERIC Educational Resources Information Center

    Park, Sunyoung; Hong, Sehee

    2016-01-01

    Meta-analysis is a statistical method that is increasingly utilized to combine and compare the results of previous primary studies. However, because of the lack of comprehensive guidelines for how to use meta-analysis, many meta-analysis studies have failed to consider important aspects, such as statistical programs, power analysis, publication…

  7. Advantages of Social Network Analysis in Educational Research

    ERIC Educational Resources Information Center

    Ushakov, K. M.; Kukso, K. N.

    2015-01-01

    Currently one of the main tools for the large scale studies of schools is statistical analysis. Although it is the most common method and it offers greatest opportunities for analysis, there are other quantitative methods for studying schools, such as network analysis. We discuss the potential advantages that network analysis has for educational…

  8. Study designs, use of statistical tests, and statistical analysis software choice in 2015: Results from two Pakistani monthly Medline indexed journals.

    PubMed

    Shaikh, Masood Ali

    2017-09-01

    Assessment of research articles in terms of study designs used, statistical tests applied and the use of statistical analysis programmes help determine research activity profile and trends in the country. In this descriptive study, all original articles published by Journal of Pakistan Medical Association (JPMA) and Journal of the College of Physicians and Surgeons Pakistan (JCPSP), in the year 2015 were reviewed in terms of study designs used, application of statistical tests, and the use of statistical analysis programmes. JPMA and JCPSP published 192 and 128 original articles, respectively, in the year 2015. Results of this study indicate that cross-sectional study design, bivariate inferential statistical analysis entailing comparison between two variables/groups, and use of statistical software programme SPSS to be the most common study design, inferential statistical analysis, and statistical analysis software programmes, respectively. These results echo previously published assessment of these two journals for the year 2014.

  9. The Big Picture: A Meta-Analysis of Program Effectiveness Research on English Language Learners

    ERIC Educational Resources Information Center

    Rolstad, Kellie; Mahoney, Kate; Glass, Gene V.

    2005-01-01

    This article presents a meta-analysis of program effectiveness research on English language learners. The study includes a corpus of 17 studies conducted since Willig's earlier meta-analysis and uses Glass, McGaw, and Smith's strategy of including as many studies as possible in the analysis rather than excluding some on the basis of a priori…

  10. Meta-Analysis of the Effect of Exercise Programs for Individuals with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Shin, In-Soo; Park, Eun-Young

    2012-01-01

    The purpose of this study was to examine the effects of physical exercise programs on individuals with intellectual disabilities (ID). This meta-analysis analyzed 67 effect sizes and 14 studies and calculated the standardized mean difference in effect size. The unit of analysis for overall effects was the study, and the sub-group analysis focused…

  11. An overview of meta-analysis for clinicians.

    PubMed

    Lee, Young Ho

    2018-03-01

    The number of medical studies being published is increasing exponentially, and clinicians must routinely process large amounts of new information. Moreover, the results of individual studies are often insufficient to provide confident answers, as their results are not consistently reproducible. A meta-analysis is a statistical method for combining the results of different studies on the same topic and it may resolve conflicts among studies. Meta-analysis is being used increasingly and plays an important role in medical research. This review introduces the basic concepts, steps, advantages, and caveats of meta-analysis, to help clinicians understand it in clinical practice and research. A major advantage of a meta-analysis is that it produces a precise estimate of the effect size, with considerably increased statistical power, which is important when the power of the primary study is limited because of a small sample size. A meta-analysis may yield conclusive results when individual studies are inconclusive. Furthermore, meta-analyses investigate the source of variation and different effects among subgroups. In summary, a meta-analysis is an objective, quantitative method that provides less biased estimates on a specific topic. Understanding how to conduct a meta-analysis aids clinicians in the process of making clinical decisions.

  12. Detailed weather and terrain analysis for aircraft noise modeling

    DOT National Transportation Integrated Search

    2013-04-30

    A study has been conducted supporting refinement and development of FAAs airport environmental analysis tools. Tasks conducted in this study are: (1) updated analysis of the 1997 KDEN noise model validation study with newer versions of INM and rel...

  13. [Report quality evaluation of systematic review or Meta-analysis published in China Journal of Chinese Materia Medica].

    PubMed

    Zhang, Yan; Yu, Dan-Dan; Cui, De-Hua; Liao, Xing; Guo, Hua

    2018-03-01

    To evaluate the report quality of intervention-related systematic reviews or Meta-analysis published in China Journal of Chinese Materia Medica, we searched CNKI and China Journal of Chinese Materia Medica webpages to collect intervention-related systematic reviews or Meta-analysis since the first issue of the magazine. A total of 40 systematic reviews or Meta-analysis reports were included, including one network Meta-analysis. According to the PRISMA statement published in 2009, the report quality of the systematic reviews or Meta-analysis was evaluated. According to the results, 3 had the low quality, 30 had the medium quality, and 7 had the high quality. The average score for all of items was 30 points (21-30.5 points for the medium quality). The 17 high-quality (31-40 points) report items were title, rationale, objectives, information sources, study selection, data collection process, data items, risk of bias in individual studies, summary measures, risk of bias across studies, study selection, study characteristics, risk of bias within studies, results of individual studies, synthesis of results, risk of bias across studies and funding; the 4 medium-quality (21-30.5 points) reporting items were eligibility criteria, search, limitations and conclusions; and the 6 low-quality (<=20.5 points) reporting items were structured summary, protocol and registration, synthesis of results, additional analysis (No.16), additional analysis (No.23) and summary of evidence. Through the analysis, it is found that the report quality of intervention-related systematic reviews or Meta-analysis published in China Journal of Chinese Materia Medica is medium, and it is necessary to improve the quality standard of the report. Copyright© by the Chinese Pharmaceutical Association.

  14. Particle Analysis Pitfalls

    NASA Technical Reports Server (NTRS)

    Hughes, David; Dazzo, Tony

    2007-01-01

    This viewgraph presentation reviews the use of particle analysis to assist in preparing for the 4th Hubble Space Telescope (HST) Servicing mission. During this mission the Space Telescope Imaging Spectrograph (STIS) will be repaired. The particle analysis consisted of Finite element mesh creation, Black-body viewfactors generated using I-DEAS TMG Thermal Analysis, Grey-body viewfactors calculated using Markov method, Particle distribution modeled using an iterative Monte Carlo process, (time-consuming); in house software called MASTRAM, Differential analysis performed in Excel, and Visualization provided by Tecplot and I-DEAS. Several tests were performed and are reviewed: Conformal Coat Particle Study, Card Extraction Study, Cover Fastener Removal Particle Generation Study, and E-Graf Vibration Particulate Study. The lessons learned during this analysis are also reviewed.

  15. TOXICOGENOMIC ANALYSIS INCORPORATING OPERON-TRANSCRIPTIONAL COUPLING AND TOXICANT CONCENTRATRION-EXPRESSION RESPONSE: Analysis of MX-Treated Salmonella

    EPA Science Inventory

    What is the study? This study is the first to use microarray analysis in the Ames strains of Salmonella. The microarray chips were custom-designed for this study and are not commercially available, and we evaluated the well-studied drinking water mutagen, MX. Because much inform...

  16. A Meta-Analysis of Cross Sectional Studies Investigating Language in Maltreated Children

    ERIC Educational Resources Information Center

    Lum, Jarrad A. G.; Powell, Martine; Timms, Lydia; Snow, Pamela

    2015-01-01

    Purpose: In this review article, meta-analysis was used to summarize research investigating language skills in maltreated children. Method: A systematic search of published studies was undertaken. Studies were included in the meta-analysis if they investigated language skills in groups comprising maltreated and nonmaltreated children. Studies were…

  17. Dimensions of Intuition: First-Round Validation Studies

    ERIC Educational Resources Information Center

    Vrugtman, Rosanne

    2009-01-01

    This study utilized confirmatory factor analysis (CFA), canonical correlation analysis (CCA), regression analysis (RA), and correlation analysis (CA) for first-round validation of the researcher's Dimensions of Intuition (DOI) instrument. The DOI examined 25 personal characteristics and situations purportedly predictive of intuition. Data was…

  18. Meta-analysis: An Approach to the Synthesis of Research Results.

    ERIC Educational Resources Information Center

    Glass, Gene V.

    1982-01-01

    Discusses three general characteristics and four criticisms of meta-analysis (statistical analysis of the summary findings of many research studies). Illustrates application of meta-analysis on research studies relating to school class size and achievement and inquiry teaching of biology. (JN)

  19. Structural, vibrational, thermal and optical studies of organic single crystal: Benzotriazolium p-toluene sulfonate (BTPTS)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kumar, R. Ramesh; Sathya, P.; Gopalakrishnan, R., E-mail: krgkrishnan@yahoo.com

    Benzotriazolium p-toluene sulfonate (BTPTS) was grown by solution growth technique. The powder X-ray diffraction analysis was carried out to evaluate crystal system of the compound. LeBail Profile fitting analysis was performed to extract the individual peak intensities. FTIR spectrum analysis was recorded to study vibration frequencies of the prepared organic salt. Thermal studies were carried out using TG-DSC analysis. Optical absorption and energy band gap of the title compound was evaluated by UV-Vis spectral study.

  20. Global satellite triangulation and trilateration for the National Geodetic Satellite Program (solutions WN 12, 14 and 16). [study and analysis of data from artificial satellites

    NASA Technical Reports Server (NTRS)

    Mueller, I. I.; Kumar, M.; Reilly, J. P.; Saxena, N.; Soler, T.

    1973-01-01

    A multi-year study and analysis of data from satellites launched specifically for geodetic purposes and from other satellites useful in geodetic studies was conducted. The program of work included theoretical studies and analysis for the geometric determination of station positions derived from photographic observations of both passive and active satellites and from range observations. The current status of data analysis, processing and results are examined.

  1. Combining multiple imputation and meta-analysis with individual participant data

    PubMed Central

    Burgess, Stephen; White, Ian R; Resche-Rigon, Matthieu; Wood, Angela M

    2013-01-01

    Multiple imputation is a strategy for the analysis of incomplete data such that the impact of the missingness on the power and bias of estimates is mitigated. When data from multiple studies are collated, we can propose both within-study and multilevel imputation models to impute missing data on covariates. It is not clear how to choose between imputation models or how to combine imputation and inverse-variance weighted meta-analysis methods. This is especially important as often different studies measure data on different variables, meaning that we may need to impute data on a variable which is systematically missing in a particular study. In this paper, we consider a simulation analysis of sporadically missing data in a single covariate with a linear analysis model and discuss how the results would be applicable to the case of systematically missing data. We find in this context that ensuring the congeniality of the imputation and analysis models is important to give correct standard errors and confidence intervals. For example, if the analysis model allows between-study heterogeneity of a parameter, then we should incorporate this heterogeneity into the imputation model to maintain the congeniality of the two models. In an inverse-variance weighted meta-analysis, we should impute missing data and apply Rubin's rules at the study level prior to meta-analysis, rather than meta-analyzing each of the multiple imputations and then combining the meta-analysis estimates using Rubin's rules. We illustrate the results using data from the Emerging Risk Factors Collaboration. PMID:23703895

  2. Statistical analysis of Skylab 3. [endocrine/metabolic studies of astronauts

    NASA Technical Reports Server (NTRS)

    Johnston, D. A.

    1974-01-01

    The results of endocrine/metabolic studies of astronauts on Skylab 3 are reported. One-way analysis of variance, contrasts, two-way unbalanced analysis of variance, and analysis of periodic changes in flight are included. Results for blood tests, and urine tests are presented.

  3. Implementation and reporting of causal mediation analysis in 2015: a systematic review in epidemiological studies.

    PubMed

    Liu, Shao-Hsien; Ulbricht, Christine M; Chrysanthopoulou, Stavroula A; Lapane, Kate L

    2016-07-20

    Causal mediation analysis is often used to understand the impact of variables along the causal pathway of an occurrence relation. How well studies apply and report the elements of causal mediation analysis remains unknown. We systematically reviewed epidemiological studies published in 2015 that employed causal mediation analysis to estimate direct and indirect effects of observed associations between an exposure on an outcome. We identified potential epidemiological studies through conducting a citation search within Web of Science and a keyword search within PubMed. Two reviewers independently screened studies for eligibility. For eligible studies, one reviewer performed data extraction, and a senior epidemiologist confirmed the extracted information. Empirical application and methodological details of the technique were extracted and summarized. Thirteen studies were eligible for data extraction. While the majority of studies reported and identified the effects of measures, most studies lacked sufficient details on the extent to which identifiability assumptions were satisfied. Although most studies addressed issues of unmeasured confounders either from empirical approaches or sensitivity analyses, the majority did not examine the potential bias arising from the measurement error of the mediator. Some studies allowed for exposure-mediator interaction and only a few presented results from models both with and without interactions. Power calculations were scarce. Reporting of causal mediation analysis is varied and suboptimal. Given that the application of causal mediation analysis will likely continue to increase, developing standards of reporting of causal mediation analysis in epidemiological research would be prudent.

  4. Deriving percentage study weights in multi-parameter meta-analysis models: with application to meta-regression, network meta-analysis and one-stage individual participant data models.

    PubMed

    Riley, Richard D; Ensor, Joie; Jackson, Dan; Burke, Danielle L

    2017-01-01

    Many meta-analysis models contain multiple parameters, for example due to multiple outcomes, multiple treatments or multiple regression coefficients. In particular, meta-regression models may contain multiple study-level covariates, and one-stage individual participant data meta-analysis models may contain multiple patient-level covariates and interactions. Here, we propose how to derive percentage study weights for such situations, in order to reveal the (otherwise hidden) contribution of each study toward the parameter estimates of interest. We assume that studies are independent, and utilise a decomposition of Fisher's information matrix to decompose the total variance matrix of parameter estimates into study-specific contributions, from which percentage weights are derived. This approach generalises how percentage weights are calculated in a traditional, single parameter meta-analysis model. Application is made to one- and two-stage individual participant data meta-analyses, meta-regression and network (multivariate) meta-analysis of multiple treatments. These reveal percentage study weights toward clinically important estimates, such as summary treatment effects and treatment-covariate interactions, and are especially useful when some studies are potential outliers or at high risk of bias. We also derive percentage study weights toward methodologically interesting measures, such as the magnitude of ecological bias (difference between within-study and across-study associations) and the amount of inconsistency (difference between direct and indirect evidence in a network meta-analysis).

  5. Measurement errors in polymerase chain reaction are a confounding factor for a correct interpretation of 5-HTTLPR polymorphism effects on lifelong premature ejaculation: a critical analysis of a previously published meta-analysis of six studies.

    PubMed

    Janssen, Paddy K C; Olivier, Berend; Zwinderman, Aeilko H; Waldinger, Marcel D

    2014-01-01

    To analyze a recently published meta-analysis of six studies on 5-HTTLPR polymorphism and lifelong premature ejaculation (PE). Calculation of fraction observed and expected genotype frequencies and Hardy Weinberg equilibrium (HWE) of cases and controls. LL,SL and SS genotype frequencies of patients were subtracted from genotype frequencies of an ideal population (LL25%, SL50%, SS25%, p = 1 for HWE). Analysis of PCRs of six studies and re-analysis of the analysis and Odds ratios (ORs) reported in the recently published meta-analysis. Three studies deviated from HWE in patients and one study deviated from HWE in controls. In three studies in-HWE the mean deviation of genotype frequencies from a theoretical population not-deviating from HWE was small: LL(1.7%), SL(-2.3%), SS(0.6%). In three studies not-in-HWE the mean deviation of genotype frequencies was high: LL(-3.3%), SL(-18.5%) and SS(21.8%) with very low percentage SL genotype concurrent with very high percentage SS genotype. The most serious PCR deviations were reported in the three not-in-HWE studies. The three in-HWE studies had normal OR. In contrast, the three not-in-HWE studies had a low OR. In three studies not-in-HWE and with very low OR, inadequate PCR analysis and/or inadequate interpretation of its gel electrophoresis resulted in very low SL and a resulting shift to very high SS genotype frequency outcome. Consequently, PCRs of these three studies are not reliable. Failure to note the inadequacy of PCR tests makes such PCRs a confounding factor in clinical interpretation of genetic studies. Currently, a meta-analysis can only be performed on three studies-in-HWE. However, based on the three studies-in-HWE with OR of about 1 there is not any indication that in men with lifelong PE the frequency of LL,SL and SS genotype deviates from the general male population and/or that the SL or SS genotype is in any way associated with lifelong PE.

  6. A Case Study of a Mixed Methods Study Engaged in Integrated Data Analysis

    ERIC Educational Resources Information Center

    Schiazza, Daniela Marie

    2013-01-01

    The nascent field of mixed methods research has yet to develop a cohesive framework of guidelines and procedures for mixed methods data analysis (Greene, 2008). To support the field's development of analytical frameworks, this case study reflects on the development and implementation of a mixed methods study engaged in integrated data analysis.…

  7. A Preliminary Study on Gender Differences in Studying Systems Analysis and Design

    ERIC Educational Resources Information Center

    Lee, Fion S. L.; Wong, Kelvin C. K.

    2017-01-01

    Systems analysis and design is a crucial task in system development and is included in a typical information systems programme as a core course. This paper presented a preliminary study on gender differences in studying a systems analysis and design course of an undergraduate programme. Results indicated that male students outperformed female…

  8. Improved score statistics for meta-analysis in single-variant and gene-level association studies.

    PubMed

    Yang, Jingjing; Chen, Sai; Abecasis, Gonçalo

    2018-06-01

    Meta-analysis is now an essential tool for genetic association studies, allowing them to combine large studies and greatly accelerating the pace of genetic discovery. Although the standard meta-analysis methods perform equivalently as the more cumbersome joint analysis under ideal settings, they result in substantial power loss under unbalanced settings with various case-control ratios. Here, we investigate the power loss problem by the standard meta-analysis methods for unbalanced studies, and further propose novel meta-analysis methods performing equivalently to the joint analysis under both balanced and unbalanced settings. We derive improved meta-score-statistics that can accurately approximate the joint-score-statistics with combined individual-level data, for both linear and logistic regression models, with and without covariates. In addition, we propose a novel approach to adjust for population stratification by correcting for known population structures through minor allele frequencies. In the simulated gene-level association studies under unbalanced settings, our method recovered up to 85% power loss caused by the standard methods. We further showed the power gain of our methods in gene-level tests with 26 unbalanced studies of age-related macular degeneration . In addition, we took the meta-analysis of three unbalanced studies of type 2 diabetes as an example to discuss the challenges of meta-analyzing multi-ethnic samples. In summary, our improved meta-score-statistics with corrections for population stratification can be used to construct both single-variant and gene-level association studies, providing a useful framework for ensuring well-powered, convenient, cross-study analyses. © 2018 WILEY PERIODICALS, INC.

  9. Coherent Power Analysis in Multilevel Studies Using Parameters from Surveys

    ERIC Educational Resources Information Center

    Rhoads, Christopher

    2017-01-01

    Researchers designing multisite and cluster randomized trials of educational interventions will usually conduct a power analysis in the planning stage of the study. To conduct the power analysis, researchers often use estimates of intracluster correlation coefficients and effect sizes derived from an analysis of survey data. When there is…

  10. Combining evidence from multiple electronic health care databases: performances of one-stage and two-stage meta-analysis in matched case-control studies.

    PubMed

    La Gamba, Fabiola; Corrao, Giovanni; Romio, Silvana; Sturkenboom, Miriam; Trifirò, Gianluca; Schink, Tania; de Ridder, Maria

    2017-10-01

    Clustering of patients in databases is usually ignored in one-stage meta-analysis of multi-database studies using matched case-control data. The aim of this study was to compare bias and efficiency of such a one-stage meta-analysis with a two-stage meta-analysis. First, we compared the approaches by generating matched case-control data under 5 simulated scenarios, built by varying: (1) the exposure-outcome association; (2) its variability among databases; (3) the confounding strength of one covariate on this association; (4) its variability; and (5) the (heterogeneous) confounding strength of two covariates. Second, we made the same comparison using empirical data from the ARITMO project, a multiple database study investigating the risk of ventricular arrhythmia following the use of medications with arrhythmogenic potential. In our study, we specifically investigated the effect of current use of promethazine. Bias increased for one-stage meta-analysis with increasing (1) between-database variance of exposure effect and (2) heterogeneous confounding generated by two covariates. The efficiency of one-stage meta-analysis was slightly lower than that of two-stage meta-analysis for the majority of investigated scenarios. Based on ARITMO data, there were no evident differences between one-stage (OR = 1.50, CI = [1.08; 2.08]) and two-stage (OR = 1.55, CI = [1.12; 2.16]) approaches. When the effect of interest is heterogeneous, a one-stage meta-analysis ignoring clustering gives biased estimates. Two-stage meta-analysis generates estimates at least as accurate and precise as one-stage meta-analysis. However, in a study using small databases and rare exposures and/or outcomes, a correct one-stage meta-analysis becomes essential. Copyright © 2017 John Wiley & Sons, Ltd.

  11. The Influence of Study-Level Inference Models and Study Set Size on Coordinate-Based fMRI Meta-Analyses

    PubMed Central

    Bossier, Han; Seurinck, Ruth; Kühn, Simone; Banaschewski, Tobias; Barker, Gareth J.; Bokde, Arun L. W.; Martinot, Jean-Luc; Lemaitre, Herve; Paus, Tomáš; Millenet, Sabina; Moerkerke, Beatrijs

    2018-01-01

    Given the increasing amount of neuroimaging studies, there is a growing need to summarize published results. Coordinate-based meta-analyses use the locations of statistically significant local maxima with possibly the associated effect sizes to aggregate studies. In this paper, we investigate the influence of key characteristics of a coordinate-based meta-analysis on (1) the balance between false and true positives and (2) the activation reliability of the outcome from a coordinate-based meta-analysis. More particularly, we consider the influence of the chosen group level model at the study level [fixed effects, ordinary least squares (OLS), or mixed effects models], the type of coordinate-based meta-analysis [Activation Likelihood Estimation (ALE) that only uses peak locations, fixed effects, and random effects meta-analysis that take into account both peak location and height] and the amount of studies included in the analysis (from 10 to 35). To do this, we apply a resampling scheme on a large dataset (N = 1,400) to create a test condition and compare this with an independent evaluation condition. The test condition corresponds to subsampling participants into studies and combine these using meta-analyses. The evaluation condition corresponds to a high-powered group analysis. We observe the best performance when using mixed effects models in individual studies combined with a random effects meta-analysis. Moreover the performance increases with the number of studies included in the meta-analysis. When peak height is not taken into consideration, we show that the popular ALE procedure is a good alternative in terms of the balance between type I and II errors. However, it requires more studies compared to other procedures in terms of activation reliability. Finally, we discuss the differences, interpretations, and limitations of our results. PMID:29403344

  12. Flash Study Analysis and the Music Learning Pro-Files Project

    ERIC Educational Resources Information Center

    Cremata, Radio; Pignato, Joseph; Powell, Bryan; Smith, Gareth Dylan

    2016-01-01

    This paper introduces the Music Learning Profiles Project, and its methodological approach, flash study analysis. Flash study analysis is a method that draws heavily on extant qualitative approaches to education research, to develop broad understandings of music learning in diverse contexts. The Music Learning Profiles Project (MLPP) is an…

  13. Statistical Power in Meta-Analysis

    ERIC Educational Resources Information Center

    Liu, Jin

    2015-01-01

    Statistical power is important in a meta-analysis study, although few studies have examined the performance of simulated power in meta-analysis. The purpose of this study is to inform researchers about statistical power estimation on two sample mean difference test under different situations: (1) the discrepancy between the analytical power and…

  14. A Survey Version of Full-Profile Conjoint Analysis.

    ERIC Educational Resources Information Center

    Chrzan, Keith

    Two studies were conducted to test the viability of a survey version of full-profile conjoint analysis. Conjoint analysis describes a variety of analytic techniques for measuring subjects'"utilities," or preferences for the individual attributes or levels of attributes that constitute objects under study. The first study compared the…

  15. Terrain Analysis Procedural Guide for Railroads (Report Number 10 in the ETL Series on Guides for Army Terrain Analysis).

    DTIC Science & Technology

    1982-12-01

    study was conducted under DA Project 4A762707A855, Task C, Work 6 Unit 21, "Military Geographic Analysis Technology." This study was done under the...supplement to the Terrain Analysis Procedural Guide for Roads and Related Structures (ETL-0205, October 1979). In sparsely inhabited study areas, railroad data... study area. " W, In general, three major sources of information are available that will = be helpful in the production of factor overlays for railroads

  16. Random-effects meta-analysis: the number of studies matters.

    PubMed

    Guolo, Annamaria; Varin, Cristiano

    2017-06-01

    This paper investigates the impact of the number of studies on meta-analysis and meta-regression within the random-effects model framework. It is frequently neglected that inference in random-effects models requires a substantial number of studies included in meta-analysis to guarantee reliable conclusions. Several authors warn about the risk of inaccurate results of the traditional DerSimonian and Laird approach especially in the common case of meta-analysis involving a limited number of studies. This paper presents a selection of likelihood and non-likelihood methods for inference in meta-analysis proposed to overcome the limitations of the DerSimonian and Laird procedure, with a focus on the effect of the number of studies. The applicability and the performance of the methods are investigated in terms of Type I error rates and empirical power to detect effects, according to scenarios of practical interest. Simulation studies and applications to real meta-analyses highlight that it is not possible to identify an approach uniformly superior to alternatives. The overall recommendation is to avoid the DerSimonian and Laird method when the number of meta-analysis studies is modest and prefer a more comprehensive procedure that compares alternative inferential approaches. R code for meta-analysis according to all of the inferential methods examined in the paper is provided.

  17. Potential Pitfalls of Reporting and Bias in Observational Studies With Propensity Score Analysis Assessing a Surgical Procedure: A Methodological Systematic Review.

    PubMed

    Lonjon, Guillaume; Porcher, Raphael; Ergina, Patrick; Fouet, Mathilde; Boutron, Isabelle

    2017-05-01

    To describe the evolution of the use and reporting of propensity score (PS) analysis in observational studies assessing a surgical procedure. Assessing surgery in randomized controlled trials raises several challenges. Observational studies with PS analysis are a robust alternative for comparative effectiveness research. In this methodological systematic review, we identified all PubMed reports of observational studies with PS analysis that evaluated a surgical procedure and described the evolution of their use over time. Then, we selected a sample of articles published from August 2013 to July 2014 and systematically appraised the quality of reporting and potential bias of the PS analysis used. We selected 652 reports of observational studies with PS analysis. The publications increased over time, from 1 report in 1987 to 198 in 2013. Among the 129 reports assessed, 20% (n = 24) did not detail the covariates included in the PS and 77% (n = 100) did not report a justification for including these covariates in the PS. The rate of missing data for potential covariates was reported in 9% of articles. When a crossover by conversion was possible, only 14% of reports (n = 12) mentioned this issue. For matched analysis, 10% of articles reported all 4 key elements that allow for reproducibility of a PS-matched analysis (matching ratio, method to choose the nearest neighbors, replacement and method for statistical analysis). Observational studies with PS analysis in surgery are increasing in frequency, but specific methodological issues and weaknesses in reporting exist.

  18. QUINCE System; State-of-the-Art Review

    DTIC Science & Technology

    1978-06-01

    linguistic data base in terms of semantic feature set, interlingual transfer component, contrastive lexical/syntactic studies and contextual analysis ...and Syntactical Studies 3.3.1 Contrastlve Lexical Studies 3.3.2 Contrastlve Syntactic Studies 3.4 Contextual Analysis 3.4.1 Elided Subjects...and English, combined with contextual analysis of language- specific characteristics of Chinese ^re offered as the most promising solutions In this

  19. Impact of Using History of Mathematics on Students' Mathematics Attitude: A Meta-Analysis Study

    ERIC Educational Resources Information Center

    Bütüner, Suphi Onder

    2015-01-01

    The main objective of hereby study is to unearth the big picture, reaching studies about influence of using history of mathematics on attitude of mathematics among students. 6 studies with a total effect size of 14 that comply with coding protocol and comprise statistical values necessary for meta-analysis are combined via meta-analysis method…

  20. Occupational and environmental scleroderma. Systematic review and meta-analysis.

    PubMed

    Rubio-Rivas, Manuel; Moreno, Rafael; Corbella, Xavier

    2017-03-01

    The etiology of systemic sclerosis (SSc) remains unknown; however, several occupational and environmental factors have been implicated. Our objective was to perform a meta-analysis of all studies published on SSc associated with occupational and environmental exposure. The review was undertaken by means of MEDLINE and SCOPUS from 1960 to 2014 and using the terms: "systemic," "scleroderma," or "systemic sclerosis/chemically induced" [MesH]. The Newcastle-Ottawa Scale was used for the qualifying assessment. The inverse variance-weighted method was performed. The meta-analysis of silica exposure included 15 case-control studies [overall OR 2.81 (95%CI 1.86-4.23; p < 0.001)] and 4 cohort studies [overall RR 17.52 (95%CI 5.98-51.37; p < 0.001)]; the meta-analysis of solvents exposure included 13 case-control studies (overall OR 2.00 [95%CI 1.32-3.02; p = 0.001); the meta-analysis of breast implants exposure included 4 case-control studies (overall OR 1.68 (95%CI 1.65-1.71; p < 0.001)) and 6 cohort studies (overall RR 2.13 (95%CI 0.86-5.27; p = 0.10)); the meta-analysis of epoxy resins exposure included 4 case-control studies (overall OR 2.97 (95%CI 2.31-3.83; p < 0.001)), the meta-analysis of pesticides exposure included 3 case-control studies (overall OR 1.02 (95%CI 0.78-1.32; p = 0.90)) and, finally, the meta-analysis of welding fumes exposure included 4 studies (overall OR 1.29 (95%CI 0.44-3.74; p = 0.64)). Not enough studies citing risks related to hair dyes have been published to perform an accurate meta-analysis. Silica and solvents were the two most likely substances related to the pathogenesis of SSc. While silica is involved in particular jobs, solvents are widespread and more people are at risk of having incidental contact with them.

  1. Statistical power analysis of cardiovascular safety pharmacology studies in conscious rats.

    PubMed

    Bhatt, Siddhartha; Li, Dingzhou; Flynn, Declan; Wisialowski, Todd; Hemkens, Michelle; Steidl-Nichols, Jill

    2016-01-01

    Cardiovascular (CV) toxicity and related attrition are a major challenge for novel therapeutic entities and identifying CV liability early is critical for effective derisking. CV safety pharmacology studies in rats are a valuable tool for early investigation of CV risk. Thorough understanding of data analysis techniques and statistical power of these studies is currently lacking and is imperative for enabling sound decision-making. Data from 24 crossover and 12 parallel design CV telemetry rat studies were used for statistical power calculations. Average values of telemetry parameters (heart rate, blood pressure, body temperature, and activity) were logged every 60s (from 1h predose to 24h post-dose) and reduced to 15min mean values. These data were subsequently binned into super intervals for statistical analysis. A repeated measure analysis of variance was used for statistical analysis of crossover studies and a repeated measure analysis of covariance was used for parallel studies. Statistical power analysis was performed to generate power curves and establish relationships between detectable CV (blood pressure and heart rate) changes and statistical power. Additionally, data from a crossover CV study with phentolamine at 4, 20 and 100mg/kg are reported as a representative example of data analysis methods. Phentolamine produced a CV profile characteristic of alpha adrenergic receptor antagonism, evidenced by a dose-dependent decrease in blood pressure and reflex tachycardia. Detectable blood pressure changes at 80% statistical power for crossover studies (n=8) were 4-5mmHg. For parallel studies (n=8), detectable changes at 80% power were 6-7mmHg. Detectable heart rate changes for both study designs were 20-22bpm. Based on our results, the conscious rat CV model is a sensitive tool to detect and mitigate CV risk in early safety studies. Furthermore, these results will enable informed selection of appropriate models and study design for early stage CV studies. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Final definition and preliminary design study for the initial atmospheric cloud physics laboratory, a Spacelab mission payload

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The following areas related to the final definition and preliminary design study of the initial atmospheric cloud physics laboratory (ACPL) were covered: (1) proposal organization, personnel, schedule, and project management, (2) proposed configurations, (3) study objectives, (4) ACPL experiment program listing and description, (5) mission/flight flexibility and modularity/commonality, (6) study plan, and (7) description of following tasks: requirement analysis and definition task flow, systems analysis and trade studies, subsystem analysis and trade studies, specifications and interface control documents, preliminary design task flow, work breakdown structure, programmatic analysis and planning, and project costs. Finally, an overview of the scientific requirements was presented.

  3. Analysis of Information Content in High-Spectral Resolution Sounders using Subset Selection Analysis

    NASA Technical Reports Server (NTRS)

    Velez-Reyes, Miguel; Joiner, Joanna

    1998-01-01

    In this paper, we summarize the results of the sensitivity analysis and data reduction carried out to determine the information content of AIRS and IASI channels. The analysis and data reduction was based on the use of subset selection techniques developed in the linear algebra and statistical community to study linear dependencies in high dimensional data sets. We applied the subset selection method to study dependency among channels by studying the dependency among their weighting functions. Also, we applied the technique to study the information provided by the different levels in which the atmosphere is discretized for retrievals and analysis. Results from the method correlate well with intuition in many respects and point out to possible modifications for band selection in sensor design and number and location of levels in the analysis process.

  4. Alcohol Intake and Risk of Thyroid Cancer: A Meta-Analysis of Observational Studies.

    PubMed

    Hong, Seung-Hee; Myung, Seung-Kwon; Kim, Hyeon Suk

    2017-04-01

    The purpose of this study was to assess whether alcohol intake is associated with the risk of thyroid cancer by a meta-analysis of observational studies. We searched PubMed and EMBASE in June of 2015 to locate eligible studies. We included observational studies such as cross-sectional studies, case-control studies, and cohort studies reporting odd ratios (ORs) or relative risk (RRs) with 95% confidence intervals (CIs). We included 33 observational studies with two cross-sectional studies, 20 case-controls studies, and 11 cohort studies, which involved a total of 7,725 thyroid cancer patients and 3,113,679 participants without thyroid cancer in the final analysis. In the fixed-effect model meta-analysis of all 33 studies, we found that alcohol intake was consistently associated with a decreased risk of thyroid cancer (OR or RR, 0.74; 95% CI, 0.67 to 0.83; I 2 =38.6%). In the subgroup meta-analysis by type of study, alcohol intake also decreased the risk of thyroid cancer in both case-control studies (OR, 0.77; 95% CI, 0.65 to 0.92; I 2 =29.5%; n=20) and cohort studies (RR, 0.70; 95% CI, 0.60 to 0.82; I 2 =0%; n=11). Moreover, subgroup meta-analyses by type of thyroid cancer, gender, amount of alcohol consumed, and methodological quality of study showed that alcohol intake was significantly associated with a decreased risk of thyroid cancer. The current meta-analysis of observational studies found that, unlike most of other types of cancer, alcohol intake decreased the risk of thyroid cancer.

  5. Some applications of categorical data analysis to epidemiological studies.

    PubMed Central

    Grizzle, J E; Koch, G G

    1979-01-01

    Several examples of categorized data from epidemiological studies are analyzed to illustrate that more informative analysis than tests of independence can be performed by fitting models. All of the analyses fit into a unified conceptual framework that can be performed by weighted least squares. The methods presented show how to calculate point estimate of parameters, asymptotic variances, and asymptotically valid chi 2 tests. The examples presented are analysis of relative risks estimated from several 2 x 2 tables, analysis of selected features of life tables, construction of synthetic life tables from cross-sectional studies, and analysis of dose-response curves. PMID:540590

  6. Identifying Effective Spelling Interventions Using a Brief Experimental Analysis and Extended Analysis

    ERIC Educational Resources Information Center

    McCurdy, Merilee; Clure, Lynne F.; Bleck, Amanda A.; Schmitz, Stephanie L.

    2016-01-01

    Spelling is an important skill that is crucial to effective written communication. In this study, brief experimental analysis procedures were used to examine spelling instruction strategies (e.g., whole word correction; word study strategy; positive practice; and cover, copy, and compare) for four students. In addition, an extended analysis was…

  7. Concepts of Cost and Cost Analysis for Higher Education.

    ERIC Educational Resources Information Center

    Brinkman, Paul T.; Allen, Richard H.

    1986-01-01

    Concepts of costs and cost analysis in higher education are examined, along with how to prepare for a cost study. Specific cost analysis techniques are identified, along with types of data generated and potential problems. In preparing for cost studies, it is important to consider: purpose, types of cost analysis, types of cost, common…

  8. Investigating Primary School Teachers' Perception about Democracy through Metaphor Analysis

    ERIC Educational Resources Information Center

    Nasirci, Hasan; Sadik, Fatma

    2018-01-01

    The aim of this study is to examine democracy perception of classroom teachers via metaphor analysis. Study group for research is formed of 253 classroom teachers. "Democracy Metaphors Questionnaire" (DMQ) has been used in collecting data. Content analysis has been used on analysis of qualitative data of research and descriptive…

  9. The Development of Practical Item Analysis Program for Indonesian Teachers

    ERIC Educational Resources Information Center

    Muhson, Ali; Lestari, Barkah; Supriyanto; Baroroh, Kiromim

    2017-01-01

    Item analysis has essential roles in the learning assessment. The item analysis program is designed to measure student achievement and instructional effectiveness. This study was aimed to develop item-analysis program and verify its feasibility. This study uses a Research and Development (R & D) model. The procedure includes designing and…

  10. [Diversity and frequency of scientific research design and statistical methods in the "Arquivos Brasileiros de Oftalmologia": a systematic review of the "Arquivos Brasileiros de Oftalmologia"--1993-2002].

    PubMed

    Crosta, Fernando; Nishiwaki-Dantas, Maria Cristina; Silvino, Wilmar; Dantas, Paulo Elias Correa

    2005-01-01

    To verify the frequency of study design, applied statistical analysis and approval by institutional review offices (Ethics Committee) of articles published in the "Arquivos Brasileiros de Oftalmologia" during a 10-year interval, with later comparative and critical analysis by some of the main international journals in the field of Ophthalmology. Systematic review without metanalysis was performed. Scientific papers published in the "Arquivos Brasileiros de Oftalmologia" between January 1993 and December 2002 were reviewed by two independent reviewers and classified according to the applied study design, statistical analysis and approval by the institutional review offices. To categorize those variables, a descriptive statistical analysis was used. After applying inclusion and exclusion criteria, 584 articles for evaluation of statistical analysis and, 725 articles for evaluation of study design were reviewed. Contingency table (23.10%) was the most frequently applied statistical method, followed by non-parametric tests (18.19%), Student's t test (12.65%), central tendency measures (10.60%) and analysis of variance (9.81%). Of 584 reviewed articles, 291 (49.82%) presented no statistical analysis. Observational case series (26.48%) was the most frequently used type of study design, followed by interventional case series (18.48%), observational case description (13.37%), non-random clinical study (8.96%) and experimental study (8.55%). We found a higher frequency of observational clinical studies, lack of statistical analysis in almost half of the published papers. Increase in studies with approval by institutional review Ethics Committee was noted since it became mandatory in 1996.

  11. Use of benzodiazepine and risk of cancer: A meta-analysis of observational studies.

    PubMed

    Kim, Hong-Bae; Myung, Seung-Kwon; Park, Yon Chul; Park, Byoungjin

    2017-02-01

    Several observational epidemiological studies have reported inconsistent results on the association between the use of benzodiazepine and the risk of cancer. We investigated the association by using a meta-analysis. We searched PubMed, EMBASE, and the bibliographies of relevant articles to locate additional publications in January 2016. Three evaluators independently reviewed and selected eligible studies based on predetermined selection criteria. Of 796 articles meeting our initial criteria, a total of 22 observational epidemiological studies with 18 case-control studies and 4 cohort studies were included in the final analysis. Benzodiazepine use was significantly associated with an increased risk of cancer (odds ratio [OR] or relative risk [RR] 1.19; 95% confidence interval 1.16-1.21) in a random-effects meta-analysis of all studies. Subgroup meta-analyses by various factors such as study design, type of case-control study, study region, and methodological quality of study showed consistent findings. Also, a significant dose-response relationship was observed between the use of benzodiazepine and the risk of cancer (p for trend <0.01). The current meta-analysis of observational epidemiological studies suggests that benzodiazepine use is associated with an increased risk of cancer. © 2016 UICC.

  12. Birth Weight and Acute Childhood Leukemia: A Meta-analysis of Observational Studies

    DTIC Science & Technology

    2005-03-22

    22 MAR 2005 2. REPORT TYPE 3. DATES COVERED - 4. TITLE AND SUBTITLE Birth Weight and Acute Childhood Leukemia: A Meta - analysis of Observational...and to quantify the strength of the relationships. We conducted a meta - analysis of nine case-control studies (published between 1991 and 2004...Based on a meta - analysis of only three case-control studies (published between 1997 and 2004) involving over 700 children with AML and over 1,900

  13. Comparative study on DuPont analysis and DEA models for measuring stock performance using financial ratio

    NASA Astrophysics Data System (ADS)

    Arsad, Roslah; Shaari, Siti Nabilah Mohd; Isa, Zaidi

    2017-11-01

    Determining stock performance using financial ratio is challenging for many investors and researchers. Financial ratio can indicate the strengths and weaknesses of a company's stock performance. There are five categories of financial ratios namely liquidity, efficiency, leverage, profitability and market ratios. It is important to interpret the ratio correctly for proper financial decision making. The purpose of this study is to compare the performance of listed companies in Bursa Malaysia using Data Envelopment Analysis (DEA) and DuPont analysis Models. The study is conducted in 2015 involving 116 consumer products companies listed in Bursa Malaysia. The estimation method of Data Envelopment Analysis computes the efficiency scores and ranks the companies accordingly. The Alirezaee and Afsharian's method of analysis based Charnes, Cooper and Rhodes (CCR) where Constant Return to Scale (CRS) is employed. The DuPont analysis is a traditional tool for measuring the operating performance of companies. In this study, DuPont analysis is used to evaluate three different aspects such as profitability, efficiency of assets utilization and financial leverage. Return on Equity (ROE) is also calculated in DuPont analysis. This study finds that both analysis models provide different rankings of the selected samples. Hypothesis testing based on Pearson's correlation, indicates that there is no correlation between rankings produced by DEA and DuPont analysis. The DEA ranking model proposed by Alirezaee and Asharian is unstable. The method cannot provide complete ranking because the values of Balance Index is equal and zero.

  14. Integrative prescreening in analysis of multiple cancer genomic studies

    PubMed Central

    2012-01-01

    Background In high throughput cancer genomic studies, results from the analysis of single datasets often suffer from a lack of reproducibility because of small sample sizes. Integrative analysis can effectively pool and analyze multiple datasets and provides a cost effective way to improve reproducibility. In integrative analysis, simultaneously analyzing all genes profiled may incur high computational cost. A computationally affordable remedy is prescreening, which fits marginal models, can be conducted in a parallel manner, and has low computational cost. Results An integrative prescreening approach is developed for the analysis of multiple cancer genomic datasets. Simulation shows that the proposed integrative prescreening has better performance than alternatives, particularly including prescreening with individual datasets, an intensity approach and meta-analysis. We also analyze multiple microarray gene profiling studies on liver and pancreatic cancers using the proposed approach. Conclusions The proposed integrative prescreening provides an effective way to reduce the dimensionality in cancer genomic studies. It can be coupled with existing analysis methods to identify cancer markers. PMID:22799431

  15. Lead and Conduct Problems: A Meta-Analysis

    ERIC Educational Resources Information Center

    Marcus, David K.; Fulton, Jessica J.; Clarke, Erin J.

    2010-01-01

    This meta-analysis examined the association between conduct problems and lead exposure. Nineteen studies on 8,561 children and adolescents were included. The average "r" across all 19 studies was 0.19 (p less than 0.001), which is considered a medium effect size. Studies that assessed lead exposure using hair element analysis yielded…

  16. A Historical Analysis of Primary Mathematics Curricula in Terms of Teaching Principles

    ERIC Educational Resources Information Center

    Ozmantar, Mehmet Fatih

    2017-01-01

    This study carries out a comparative analysis of primary mathematics curricula put into practice during Turkish Republican period. The data for this study are composed of official curricula documents which are examined in terms of teaching principles. The study adopts a qualitative approach and employs document analysis method. The official…

  17. Data Base Reexamination as Part of IDS Secondary Analysis.

    ERIC Educational Resources Information Center

    Curry, Blair H.; And Others

    Data reexamination is a critical component for any study. The complexity of the study, the time available for data base development and analysis, and the relationship of the study to educational policy-making can all increase the criticality of such reexamination. Analysis of the error levels in the National Institute of Education's Instructional…

  18. Content Analysis Coding Schemes for Online Asynchronous Discussion

    ERIC Educational Resources Information Center

    Weltzer-Ward, Lisa

    2011-01-01

    Purpose: Researchers commonly utilize coding-based analysis of classroom asynchronous discussion contributions as part of studies of online learning and instruction. However, this analysis is inconsistent from study to study with over 50 coding schemes and procedures applied in the last eight years. The aim of this article is to provide a basis…

  19. On Misconceptions about Behavior Analysis among University Students and Teachers

    ERIC Educational Resources Information Center

    Arntzen, Erik; Lokke, Jon; Lokke, Gunn; Eilertsen, Dag-Erik

    2010-01-01

    Students frequently show misconceptions regarding scientific psychology in general and basic concepts in behavior analysis in particular. We wanted to replicate the study by Lamal (1995) and to expand the study by including some additional statements. In the current study, the focus was on misconceptions about behavior analysis held by…

  20. Mapping Copper and Lead Concentrations at Abandoned Mine Areas Using Element Analysis Data from ICP–AES and Portable XRF Instruments: A Comparative Study

    PubMed Central

    Lee, Hyeongyu; Choi, Yosoon; Suh, Jangwon; Lee, Seung-Ho

    2016-01-01

    Understanding spatial variation of potentially toxic trace elements (PTEs) in soil is necessary to identify the proper measures for preventing soil contamination at both operating and abandoned mining areas. Many studies have been conducted worldwide to explore the spatial variation of PTEs and to create soil contamination maps using geostatistical methods. However, they generally depend only on inductively coupled plasma atomic emission spectrometry (ICP–AES) analysis data, therefore such studies are limited by insufficient input data owing to the disadvantages of ICP–AES analysis such as its costly operation and lengthy period required for analysis. To overcome this limitation, this study used both ICP–AES and portable X-ray fluorescence (PXRF) analysis data, with relatively low accuracy, for mapping copper and lead concentrations at a section of the Busan abandoned mine in Korea and compared the prediction performances of four different approaches: the application of ordinary kriging to ICP–AES analysis data, PXRF analysis data, both ICP–AES and transformed PXRF analysis data by considering the correlation between the ICP–AES and PXRF analysis data, and co-kriging to both the ICP–AES (primary variable) and PXRF analysis data (secondary variable). Their results were compared using an independent validation data set. The results obtained in this case study showed that the application of ordinary kriging to both ICP–AES and transformed PXRF analysis data is the most accurate approach when considers the spatial distribution of copper and lead contaminants in the soil and the estimation errors at 11 sampling points for validation. Therefore, when generating soil contamination maps for an abandoned mine, it is beneficial to use the proposed approach that incorporates the advantageous aspects of both ICP–AES and PXRF analysis data. PMID:27043594

  1. Mapping Copper and Lead Concentrations at Abandoned Mine Areas Using Element Analysis Data from ICP-AES and Portable XRF Instruments: A Comparative Study.

    PubMed

    Lee, Hyeongyu; Choi, Yosoon; Suh, Jangwon; Lee, Seung-Ho

    2016-03-30

    Understanding spatial variation of potentially toxic trace elements (PTEs) in soil is necessary to identify the proper measures for preventing soil contamination at both operating and abandoned mining areas. Many studies have been conducted worldwide to explore the spatial variation of PTEs and to create soil contamination maps using geostatistical methods. However, they generally depend only on inductively coupled plasma atomic emission spectrometry (ICP-AES) analysis data, therefore such studies are limited by insufficient input data owing to the disadvantages of ICP-AES analysis such as its costly operation and lengthy period required for analysis. To overcome this limitation, this study used both ICP-AES and portable X-ray fluorescence (PXRF) analysis data, with relatively low accuracy, for mapping copper and lead concentrations at a section of the Busan abandoned mine in Korea and compared the prediction performances of four different approaches: the application of ordinary kriging to ICP-AES analysis data, PXRF analysis data, both ICP-AES and transformed PXRF analysis data by considering the correlation between the ICP-AES and PXRF analysis data, and co-kriging to both the ICP-AES (primary variable) and PXRF analysis data (secondary variable). Their results were compared using an independent validation data set. The results obtained in this case study showed that the application of ordinary kriging to both ICP-AES and transformed PXRF analysis data is the most accurate approach when considers the spatial distribution of copper and lead contaminants in the soil and the estimation errors at 11 sampling points for validation. Therefore, when generating soil contamination maps for an abandoned mine, it is beneficial to use the proposed approach that incorporates the advantageous aspects of both ICP-AES and PXRF analysis data.

  2. Effect of High-Frequency Transcranial Magnetic Stimulation on Craving in Substance Use Disorder: A Meta-Analysis.

    PubMed

    Maiti, Rituparna; Mishra, Biswa Ranjan; Hota, Debasish

    2017-01-01

    Repetitive transcranial magnetic stimulation (rTMS), a noninvasive, neuromodulatory tool, has been used to reduce craving in different substance use disorders. There are some studies that have reported conflicting and inconclusive results; therefore, this meta-analysis was conducted to evaluate the effect of high-frequency rTMS on craving in substance use disorder and to investigate the reasons behind the inconsistency across the studies. The authors searched clinical trials from MEDLINE, Cochrane databases, and International Clinical Trials Registry Platform. The PRISMA guidelines, as well as recommended meta-analysis practices, were followed in the selection process, analysis, and reporting of the findings. The effect estimate used was the standardized mean difference (Hedge's g), and heterogeneity across the considered studies was explored using subgroup analyses. The quality assessment was done using the Cochrane risk of bias tool, and sensitivity analysis was performed to check the influences on effect size by statistical models. After screening and assessment of eligibility, finally 10 studies were included for meta-analysis, which includes six studies on alcohol and four studies on nicotine use disorder. The random-model analysis revealed a pooled effect size of 0.75 (95% CI=0.29 to 1.21, p=0.001), whereas the fixed-model analysis showed a large effect size of 0.87 (95% CI=0.63 to 1.12, p<0.00001). Subgroup analysis for alcohol use disorder showed an effect size of -0.06 (95% CI=-0.89 to 0.77, p=0.88). In the case of nicotine use disorder, random-model analysis revealed an effect size of 1.00 (95% CI=0.48 to 1.55, p=0.0001), whereas fixed-model analysis also showed a large effect size of 0.96 (95% CI=0.71 to 1.22). The present meta-analysis identified a beneficial effect of high-frequency rTMS on craving associated with nicotine use disorder but not alcohol use disorder.

  3. Meta-analysis of quantitative pleiotropic traits for next-generation sequencing with multivariate functional linear models

    PubMed Central

    Chiu, Chi-yang; Jung, Jeesun; Chen, Wei; Weeks, Daniel E; Ren, Haobo; Boehnke, Michael; Amos, Christopher I; Liu, Aiyi; Mills, James L; Ting Lee, Mei-ling; Xiong, Momiao; Fan, Ruzong

    2017-01-01

    To analyze next-generation sequencing data, multivariate functional linear models are developed for a meta-analysis of multiple studies to connect genetic variant data to multiple quantitative traits adjusting for covariates. The goal is to take the advantage of both meta-analysis and pleiotropic analysis in order to improve power and to carry out a unified association analysis of multiple studies and multiple traits of complex disorders. Three types of approximate F -distributions based on Pillai–Bartlett trace, Hotelling–Lawley trace, and Wilks's Lambda are introduced to test for association between multiple quantitative traits and multiple genetic variants. Simulation analysis is performed to evaluate false-positive rates and power of the proposed tests. The proposed methods are applied to analyze lipid traits in eight European cohorts. It is shown that it is more advantageous to perform multivariate analysis than univariate analysis in general, and it is more advantageous to perform meta-analysis of multiple studies instead of analyzing the individual studies separately. The proposed models require individual observations. The value of the current paper can be seen at least for two reasons: (a) the proposed methods can be applied to studies that have individual genotype data; (b) the proposed methods can be used as a criterion for future work that uses summary statistics to build test statistics to meta-analyze the data. PMID:28000696

  4. Meta-analysis of quantitative pleiotropic traits for next-generation sequencing with multivariate functional linear models.

    PubMed

    Chiu, Chi-Yang; Jung, Jeesun; Chen, Wei; Weeks, Daniel E; Ren, Haobo; Boehnke, Michael; Amos, Christopher I; Liu, Aiyi; Mills, James L; Ting Lee, Mei-Ling; Xiong, Momiao; Fan, Ruzong

    2017-02-01

    To analyze next-generation sequencing data, multivariate functional linear models are developed for a meta-analysis of multiple studies to connect genetic variant data to multiple quantitative traits adjusting for covariates. The goal is to take the advantage of both meta-analysis and pleiotropic analysis in order to improve power and to carry out a unified association analysis of multiple studies and multiple traits of complex disorders. Three types of approximate F -distributions based on Pillai-Bartlett trace, Hotelling-Lawley trace, and Wilks's Lambda are introduced to test for association between multiple quantitative traits and multiple genetic variants. Simulation analysis is performed to evaluate false-positive rates and power of the proposed tests. The proposed methods are applied to analyze lipid traits in eight European cohorts. It is shown that it is more advantageous to perform multivariate analysis than univariate analysis in general, and it is more advantageous to perform meta-analysis of multiple studies instead of analyzing the individual studies separately. The proposed models require individual observations. The value of the current paper can be seen at least for two reasons: (a) the proposed methods can be applied to studies that have individual genotype data; (b) the proposed methods can be used as a criterion for future work that uses summary statistics to build test statistics to meta-analyze the data.

  5. Comparison of variance estimators for meta-analysis of instrumental variable estimates

    PubMed Central

    Schmidt, AF; Hingorani, AD; Jefferis, BJ; White, J; Groenwold, RHH; Dudbridge, F

    2016-01-01

    Abstract Background: Mendelian randomization studies perform instrumental variable (IV) analysis using genetic IVs. Results of individual Mendelian randomization studies can be pooled through meta-analysis. We explored how different variance estimators influence the meta-analysed IV estimate. Methods: Two versions of the delta method (IV before or after pooling), four bootstrap estimators, a jack-knife estimator and a heteroscedasticity-consistent (HC) variance estimator were compared using simulation. Two types of meta-analyses were compared, a two-stage meta-analysis pooling results, and a one-stage meta-analysis pooling datasets. Results: Using a two-stage meta-analysis, coverage of the point estimate using bootstrapped estimators deviated from nominal levels at weak instrument settings and/or outcome probabilities ≤ 0.10. The jack-knife estimator was the least biased resampling method, the HC estimator often failed at outcome probabilities ≤ 0.50 and overall the delta method estimators were the least biased. In the presence of between-study heterogeneity, the delta method before meta-analysis performed best. Using a one-stage meta-analysis all methods performed equally well and better than two-stage meta-analysis of greater or equal size. Conclusions: In the presence of between-study heterogeneity, two-stage meta-analyses should preferentially use the delta method before meta-analysis. Weak instrument bias can be reduced by performing a one-stage meta-analysis. PMID:27591262

  6. Statistical Test of Expression Pattern (STEPath): a new strategy to integrate gene expression data with genomic information in individual and meta-analysis studies.

    PubMed

    Martini, Paolo; Risso, Davide; Sales, Gabriele; Romualdi, Chiara; Lanfranchi, Gerolamo; Cagnin, Stefano

    2011-04-11

    In the last decades, microarray technology has spread, leading to a dramatic increase of publicly available datasets. The first statistical tools developed were focused on the identification of significant differentially expressed genes. Later, researchers moved toward the systematic integration of gene expression profiles with additional biological information, such as chromosomal location, ontological annotations or sequence features. The analysis of gene expression linked to physical location of genes on chromosomes allows the identification of transcriptionally imbalanced regions, while, Gene Set Analysis focuses on the detection of coordinated changes in transcriptional levels among sets of biologically related genes. In this field, meta-analysis offers the possibility to compare different studies, addressing the same biological question to fully exploit public gene expression datasets. We describe STEPath, a method that starts from gene expression profiles and integrates the analysis of imbalanced region as an a priori step before performing gene set analysis. The application of STEPath in individual studies produced gene set scores weighted by chromosomal activation. As a final step, we propose a way to compare these scores across different studies (meta-analysis) on related biological issues. One complication with meta-analysis is batch effects, which occur because molecular measurements are affected by laboratory conditions, reagent lots and personnel differences. Major problems occur when batch effects are correlated with an outcome of interest and lead to incorrect conclusions. We evaluated the power of combining chromosome mapping and gene set enrichment analysis, performing the analysis on a dataset of leukaemia (example of individual study) and on a dataset of skeletal muscle diseases (meta-analysis approach). In leukaemia, we identified the Hox gene set, a gene set closely related to the pathology that other algorithms of gene set analysis do not identify, while the meta-analysis approach on muscular disease discriminates between related pathologies and correlates similar ones from different studies. STEPath is a new method that integrates gene expression profiles, genomic co-expressed regions and the information about the biological function of genes. The usage of the STEPath-computed gene set scores overcomes batch effects in the meta-analysis approaches allowing the direct comparison of different pathologies and different studies on a gene set activation level.

  7. [Conversation analysis for improving nursing communication].

    PubMed

    Yi, Myungsun

    2007-08-01

    Nursing communication has become more important than ever before because quality of nursing services largely depends on the quality of communication in a very competitive health care environment. This article was to introduce ways to improve nursing communication using conversation analysis. This was a review study on conversation analysis, critically examining previous studies in nursing communication and interpersonal relationships. This study provided theoretical backgrounds and basic assumptions of conversation analysis which was influenced by ethnomethodology, phenomenology, and sociolinguistic. In addition, the characteristics and analysis methods of conversation analysis were illustrated in detail. Lastly, how conversation analysis could help improve communication was shown, by examining researches using conversation analysis not only for ordinary conversations but also for extraordinary or difficult conversations such as conversations between patients with dementia and their professional nurses. Conversation analysis can help in improving nursing communication by providing various structures and patterns as well as prototypes of conversation, and by suggesting specific problems and problem-solving strategies in communication.

  8. Complexity analysis of human physiological signals based on case studies

    NASA Astrophysics Data System (ADS)

    Angelova, Maia; Holloway, Philip; Ellis, Jason

    2015-04-01

    This work focuses on methods for investigation of physiological time series based on complexity analysis. It is a part of a wider programme to determine non-invasive markers for healthy ageing. We consider two case studies investigated with actigraphy: (a) sleep and alternations with insomnia, and (b) ageing effects on mobility patterns. We illustrate, using these case studies, the application of fractal analysis to the investigation of regulation patterns and control, and change of physiological function. In the first case study, fractal analysis techniques were implemented to study the correlations present in sleep actigraphy for individuals suffering from acute insomnia in comparison with healthy controls. The aim was to investigate if complexity analysis can detect the onset of adverse health-related events. The subjects with acute insomnia displayed significantly higher levels of complexity, possibly a result of too much activity in the underlying regulatory systems. The second case study considered mobility patterns during night time and their variations with age. It showed that complexity metrics can identify change in physiological function with ageing. Both studies demonstrated that complexity analysis can be used to investigate markers of health, disease and healthy ageing.

  9. Estimating a test's accuracy using tailored meta-analysis-How setting-specific data may aid study selection.

    PubMed

    Willis, Brian H; Hyde, Christopher J

    2014-05-01

    To determine a plausible estimate for a test's performance in a specific setting using a new method for selecting studies. It is shown how routine data from practice may be used to define an "applicable region" for studies in receiver operating characteristic space. After qualitative appraisal, studies are selected based on the probability that their study accuracy estimates arose from parameters lying in this applicable region. Three methods for calculating these probabilities are developed and used to tailor the selection of studies for meta-analysis. The Pap test applied to the UK National Health Service (NHS) Cervical Screening Programme provides a case example. The meta-analysis for the Pap test included 68 studies, but at most 17 studies were considered applicable to the NHS. For conventional meta-analysis, the sensitivity and specificity (with 95% confidence intervals) were estimated to be 72.8% (65.8, 78.8) and 75.4% (68.1, 81.5) compared with 50.9% (35.8, 66.0) and 98.0% (95.4, 99.1) from tailored meta-analysis using a binomial method for selection. Thus, for a cervical intraepithelial neoplasia (CIN) 1 prevalence of 2.2%, the post-test probability for CIN 1 would increase from 6.2% to 36.6% between the two methods of meta-analysis. Tailored meta-analysis provides a method for augmenting study selection based on the study's applicability to a setting. As such, the summary estimate is more likely to be plausible for a setting and could improve diagnostic prediction in practice. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Mendelian randomization analysis of a time-varying exposure for binary disease outcomes using functional data analysis methods.

    PubMed

    Cao, Ying; Rajan, Suja S; Wei, Peng

    2016-12-01

    A Mendelian randomization (MR) analysis is performed to analyze the causal effect of an exposure variable on a disease outcome in observational studies, by using genetic variants that affect the disease outcome only through the exposure variable. This method has recently gained popularity among epidemiologists given the success of genetic association studies. Many exposure variables of interest in epidemiological studies are time varying, for example, body mass index (BMI). Although longitudinal data have been collected in many cohort studies, current MR studies only use one measurement of a time-varying exposure variable, which cannot adequately capture the long-term time-varying information. We propose using the functional principal component analysis method to recover the underlying individual trajectory of the time-varying exposure from the sparsely and irregularly observed longitudinal data, and then conduct MR analysis using the recovered curves. We further propose two MR analysis methods. The first assumes a cumulative effect of the time-varying exposure variable on the disease risk, while the second assumes a time-varying genetic effect and employs functional regression models. We focus on statistical testing for a causal effect. Our simulation studies mimicking the real data show that the proposed functional data analysis based methods incorporating longitudinal data have substantial power gains compared to standard MR analysis using only one measurement. We used the Framingham Heart Study data to demonstrate the promising performance of the new methods as well as inconsistent results produced by the standard MR analysis that relies on a single measurement of the exposure at some arbitrary time point. © 2016 WILEY PERIODICALS, INC.

  11. Evaluating the Minimal Specimens From Endoscopic Ultrasound-Guided Fine-Needle Aspiration in Pancreatic Masses

    PubMed Central

    Park, Joo Kyung; Kang, Ki Joo; Oh, Cho Rong; Lee, Jong Kyun; Lee, Kyu Taek; Jang, Kee Taek; Park, Sang-Mo; Lee, Kwang Hyuck

    2016-01-01

    Abstract Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has become one of the most useful diagnostic modalities for the diagnosis of pancreatic mass. The aim of this study was to investigate the role of analyzing the minimal specimens obtained by EUS-FNA for the diagnosis of solid masses of pancreas. This study consisted of retrospective and prospective analyses. The retrospective study was performed on 116 patients who underwent EUS-FNA of solid masses for cytological smear, histological analysis, and combined analysis including immunohistochemical (IHC) staining. In the prospective study, 79 patients were enrolled to evaluate the quality and accuracy of EUS-FNA histological analysis and feasibility of IHC staining. The final diagnoses of all patients included pancreatic cancer (n = 126), nonpancreatic cancer (n = 21), other neoplasm (n = 27), and benign lesions (n = 21). In our retrospective study, the combined analysis was more sensitive than cytological analysis alone (P < 0.01). The overall sensitivity of cytology, histology, and combined analysis was 69.8%, 67.2%, and 81.8%, respectively. In the prospective analysis, 64.2% of all punctures were helpful for determining the diagnosis and 40.7% provided sufficient tissue for IHC staining. Histological analysis was helpful for diagnosis in 74.7% of patients. IHC staining was necessary for a definite diagnosis in 11.4% of patients, especially in the cases of nonmalignant pancreatic mass. Histological analysis and IHC study of EUS-FNA specimens was useful for the accurate diagnosis of pancreatic and peripancreatic lesions. Combined analysis showed significantly higher sensitivity than cytology alone because IHC staining was helpful for a diagnosis in some patients. PMID:27227937

  12. A synthesis and meta-analysis of reading interventions using social studies content for students with learning disabilities.

    PubMed

    Swanson, Elizabeth; Hairrell, Angela; Kent, Shawn; Ciullo, Stephen; Wanzek, Jeanne A; Vaughn, Sharon

    2014-01-01

    A synthesis and meta-analysis of the extant research on the effects of reading interventions delivered using social studies content for students with learning disabilities in kindergarten through Grade 12 is provided. A total of 27 studies met criteria for the synthesis, with 16 studies providing sufficient data for inclusion in the meta-analysis. Reading interventions implemented within the context of social studies have employed the use of graphic organizers, mnemonics, reading and answering questions, guided notes, and multicomponent comprehension instruction. The overall mean effect size for interventions included in the meta-analysis was 1.02, indicating that reading interventions delivered using social studies content have a substantial positive effect on outcomes among students with learning disabilities.

  13. Grays Harbor and Chehalis River Improvements to Navigation Environmental Studies. Grays Harbor Ocean Disposal Study. Literature Review and Preliminary Benthic Sampling,

    DTIC Science & Technology

    1980-05-01

    transects extending approximately 16 kilometers from the mouth of Grays Harbor. Sub- samples were taken for grain size analysis and wood content. The...samples were thert was".d on a 1.0 mm screen to separate benthic organisms from non-living materials. Consideration of the grain size analysis ...Nutrients 17 B. Field Study 18 Methods 18 Grain Size Analysis 18 Wood Analysis 21 Wood Fragments 21 Sediment Types 21 Discussion 24 IV. BIOLOGICAL

  14. Land utilization and water resource inventories over extended test sites

    NASA Technical Reports Server (NTRS)

    Hoffer, R. M.

    1972-01-01

    In addition to the work on the corn blight this year, several other analysis tests were completed which resulted in significant findings. These aspects are discussed as follows: (1) field spectral measurements of soil conditions; (2) analysis of extended test site data; this discussion involves three different sets of data analysis sequences; (3) urban land use analysis, for studying water runoff potentials; and (4) thermal data quality study, as an expansion of our water resources studies involving temperature calibration techniques.

  15. Taxicab Correspondence Analysis of Contingency Tables with One Heavyweight Column

    ERIC Educational Resources Information Center

    Choulakian, V.

    2008-01-01

    The aim of this paper is to study the analysis of contingency tables with one heavyweight column or one heavyweight entry by taxicab correspondence analysis (TCA). Given that the mathematics of TCA is simpler than the mathematics of correspondence analysis (CA), the influence of one heavyweight column on the outputs of TCA is studied explicitly…

  16. Analysis of Documents Published in Scopus Database on Foreign Language Learning through Mobile Learning: A Content Analysis

    ERIC Educational Resources Information Center

    Uzunboylu, Huseyin; Genc, Zeynep

    2017-01-01

    The purpose of this study is to determine the recent trends in foreign language learning through mobile learning. The study was conducted employing document analysis and related content analysis among the qualitative research methodology. Through the search conducted on Scopus database with the key words "mobile learning and foreign language…

  17. Standardized Regression Coefficients as Indices of Effect Sizes in Meta-Analysis

    ERIC Educational Resources Information Center

    Kim, Rae Seon

    2011-01-01

    When conducting a meta-analysis, it is common to find many collected studies that report regression analyses, because multiple regression analysis is widely used in many fields. Meta-analysis uses effect sizes drawn from individual studies as a means of synthesizing a collection of results. However, indices of effect size from regression analyses…

  18. Meta-analysis: Association between hypoglycaemia and serious adverse events in older patients.

    PubMed

    Mattishent, Katharina; Loke, Yoon Kong

    2016-07-01

    We aimed to conduct a meta-analysis of serious adverse events (macro- and microvascular events, falls and fractures, death) associated with hypoglycaemia in older patients. We searched MEDLINE and EMBASE spanning a ten-year period up to March 2015 (with automated PubMed updates to October 2015). We selected observational studies reporting on hypoglycaemia and associated serious adverse events, and conducted a meta-analysis. We assessed study validity based on ascertainment of hypoglycaemia, adverse events and adjustment for confounders. We included 17 studies involving 1.86 million participants. Meta-analysis of eight studies demonstrated that hypoglycemic episodes were associated with macrovascular complications, odds ratio (OR) 1.83 (95% confidence interval [CI] 1.64, 2.05), and microvascular complications in two studies OR 1.77 (95% CI 1.49, 2.10). Meta-analysis of four studies demonstrated an association between hypoglycaemia and falls or fractures, OR 1.89 (95% CI 1.54, 2.32) and 1.92 (95% CI 1.56, 2.38) respectively. Hypoglycaemia was associated with increased likelihood of death in a meta-analysis of eight studies, OR 2.04 (95% Confidence Interval 1.68, 2.47). Our meta-analysis raises major concerns about a range of serious adverse events associated with hypoglycaemia. Clinicians should prioritize individualized therapy and closer monitoring strategies to avoid hypoglycaemia in susceptible older patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Graphical augmentations to the funnel plot assess the impact of additional evidence on a meta-analysis.

    PubMed

    Langan, Dean; Higgins, Julian P T; Gregory, Walter; Sutton, Alexander J

    2012-05-01

    We aim to illustrate the potential impact of a new study on a meta-analysis, which gives an indication of the robustness of the meta-analysis. A number of augmentations are proposed to one of the most widely used of graphical displays, the funnel plot. Namely, 1) statistical significance contours, which define regions of the funnel plot in which a new study would have to be located to change the statistical significance of the meta-analysis; and 2) heterogeneity contours, which show how a new study would affect the extent of heterogeneity in a given meta-analysis. Several other features are also described, and the use of multiple features simultaneously is considered. The statistical significance contours suggest that one additional study, no matter how large, may have a very limited impact on the statistical significance of a meta-analysis. The heterogeneity contours illustrate that one outlying study can increase the level of heterogeneity dramatically. The additional features of the funnel plot have applications including 1) informing sample size calculations for the design of future studies eligible for inclusion in the meta-analysis; and 2) informing the updating prioritization of a portfolio of meta-analyses such as those prepared by the Cochrane Collaboration. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Dietary zinc and iron intake and risk of depression: A meta-analysis.

    PubMed

    Li, Zongyao; Li, Bingrong; Song, Xingxing; Zhang, Dongfeng

    2017-05-01

    The associations between dietary zinc and iron intake and risk of depression remain controversial. Thus, we carried out a meta-analysis to evaluate these associations. A systematic search was performed in PubMed, Embase, Web of Science, Chinese National Knowledge Infrastructure (CNKI) and Wanfang databases for relevant studies up to January 2017. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random effects model. A total of 9 studies for dietary zinc intake and 3 studies for dietary iron intake were finally included in present meta-analysis. The pooled RRs with 95% CIs of depression for the highest versus lowest dietary zinc and iron intake were 0.67 (95% CI: 0.58-0.76) and 0.57 (95% CI: 0.34-0.95), respectively. In subgroup analysis by study design, the inverse association between dietary zinc intake and risk of depression remained significant in the cohort studies and cross-sectional studies. The pooled RRs (95% CIs) for depression did not substantially change in the influence analysis and subgroup analysis by adjustment for body mass index (BMI). The present meta-analysis indicates inverse associations between dietary zinc and iron intake and risk of depression. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  1. Network meta-analysis: an introduction for pharmacists.

    PubMed

    Xu, Yina; Amiche, Mohamed Amine; Tadrous, Mina

    2018-05-21

    Network meta-analysis is a new tool used to summarize and compare studies for multiple interventions, irrespective of whether these interventions have been directly evaluated against each other. Network meta-analysis is quickly becoming the standard in conducting therapeutic reviews and clinical guideline development. However, little guidance is available to help pharmacists review network meta-analysis studies in their practice. Major institutions such as the Cochrane Collaboration, Agency for Healthcare Research and Quality, Canadian Agency for Drugs and Technologies in Health, and National Institute for Health and Care Excellence Decision Support Unit have endorsed utilizing network meta-analysis to establish therapeutic evidence and inform decision making. Our objective is to introduce this novel technique to pharmacy practitioners, and highlight key assumptions behind network meta-analysis studies.

  2. Design and Analysis of a Subcritical Airfoil for High Altitude, Long Endurance Missions.

    DTIC Science & Technology

    1982-12-01

    Airfoil Design and Analysis Method ......... .... 61 Appendix D: Boundary Layer Analysis Method ............. ... 81 Appendix E: Detailed Results ofr...attack. Computer codes designed by Richard Eppler were used for this study. The airfoil was anlayzed by using a viscous effects analysis program...inverse program designed by Eppler (Ref 5) was used in this study to accomplish this part. The second step involved the analysis of the airfoil under

  3. Bleeding and pneumonia in intensive care patients given ranitidine and sucralfate for prevention of stress ulcer: meta-analysis of randomised controlled trials

    PubMed Central

    Messori, A; Trippoli, S; Vaiani, M; Gorini, M; Corrado, A

    2000-01-01

    Objectives To determine the effectiveness of ranitidine and sucralfate in the prevention of stress ulcer in critical patients and to assess if these treatments affect the risk of nosocomial pneumonia. Design Published studies retrieved through Medline and other databases. Five meta-analyses evaluated effectiveness in terms of bleeding rates (A: ranitidine v placebo; B: sucralfate v placebo) and infectious complications in terms of incidence of nosocomial pneumonia (C: ranitidine v placebo; D: sucralfate v placebo; E: ranitidine v sucralfate). Trial quality was determined with an empirical ad hoc procedure. Main outcome measures Rates of clinically important gastrointestinal bleeding and nosocomial pneumonia (compared between the two study arms and expressed with odds ratios specific for individual studies and meta-analytic summary odds ratios). Results Meta-analysis A (five studies) comprised 398 patients; meta-analysis C (three studies) comprised 311 patients; meta-analysis D (two studies) comprised 226 patients: and meta-analysis E (eight studies) comprised 1825 patients. Meta-analysis B was not carried out as the literature search selected only one clinical trial. In meta-analysis A ranitidine was found to have the same effectiveness as placebo (odds ratio of bleeding 0.72, 95% confidence interval 0.30 to 1.70, P=0.46). In placebo controlled studies (meta-analyses C and D) ranitidine and sucralfate had no influence on the incidence of nosocomial pneumonia. In comparison with sucralfate, ranitidine significantly increased the incidence of nosocomial pneumonia (meta-analysis E: 1.35, 1.07 to 1.70, P=0.012). The mean quality score in the four analyses (on a 0 to 10 scale) ranged from 5.6 in meta-analysis E to 6.6 in meta-analysis A. Conclusions Ranitidine is ineffective in the prevention of gastrointestinal bleeding in patients in intensive care and might increase the risk of pneumonia. Studies on sucralfate do not provide conclusive results. These findings are based on small numbers of patients, and firm conclusions cannot presently be proposed. PMID:11061729

  4. Studies on the factors modulating indole-3-acetic acid production in endophytic bacterial isolates from Piper nigrum and molecular analysis of ipdc gene.

    PubMed

    Jasim, B; Jimtha John, C; Shimil, V; Jyothis, M; Radhakrishnan, E K

    2014-09-01

    The study mainly aimed quantitative analysis of IAA produced by endophytic bacteria under various conditions including the presence of extract from Piper nigrum. Analysis of genetic basis of IAA production was also conducted by studying the presence and diversity of the ipdc gene among the selected isolates. Five endophytic bacteria isolated previously from P. nigrum were used for the study. The effect of temperature, pH, agitation, tryptophan concentration and plant extract on modulating IAA production of selected isolates was analysed by colorimetric method. Comparative and quantitative analysis of IAA production by colorimetric isolates under optimal culture condition was analysed by HPTLC method. Presence of ipdc gene and thereby biosynthetic basis of IAA production among the selected isolates were studied by PCR-based amplification and subsequent insilico analysis of sequence obtained. Among the selected bacterial isolates from P. nigrum, isolate PnB 8 (Klebsiella pneumoniae) was found to have the maximum yield of IAA under various conditions optimized and was confirmed by colorimetric, HPLC and HPTLC analysis. Very interestingly, the study showed stimulating effect of phytochemicals from P. nigrum on IAA production by endophytic bacteria isolated from same plant. This study is unique because of the selection of endophytes from same source for comparative and quantitative analysis of IAA production under various conditions. Study on stimulatory effect of phytochemicals on bacterial IAA production as explained in the study is a novel approach. Studies on molecular basis of IAA production which was confirmed by sequence analysis of ipdc gene make the study scientifically attractive. Even though microbial production of IAA is well known, current report on detailed optimization, effect of plant extract and molecular confirmation of IAA biosynthesis is comparatively novel in its approach. © 2014 The Society for Applied Microbiology.

  5. Functional MRI Preprocessing in Lesioned Brains: Manual Versus Automated Region of Interest Analysis

    PubMed Central

    Garrison, Kathleen A.; Rogalsky, Corianne; Sheng, Tong; Liu, Brent; Damasio, Hanna; Winstein, Carolee J.; Aziz-Zadeh, Lisa S.

    2015-01-01

    Functional magnetic resonance imaging (fMRI) has significant potential in the study and treatment of neurological disorders and stroke. Region of interest (ROI) analysis in such studies allows for testing of strong a priori clinical hypotheses with improved statistical power. A commonly used automated approach to ROI analysis is to spatially normalize each participant’s structural brain image to a template brain image and define ROIs using an atlas. However, in studies of individuals with structural brain lesions, such as stroke, the gold standard approach may be to manually hand-draw ROIs on each participant’s non-normalized structural brain image. Automated approaches to ROI analysis are faster and more standardized, yet are susceptible to preprocessing error (e.g., normalization error) that can be greater in lesioned brains. The manual approach to ROI analysis has high demand for time and expertise, but may provide a more accurate estimate of brain response. In this study, commonly used automated and manual approaches to ROI analysis were directly compared by reanalyzing data from a previously published hypothesis-driven cognitive fMRI study, involving individuals with stroke. The ROI evaluated is the pars opercularis of the inferior frontal gyrus. Significant differences were identified in task-related effect size and percent-activated voxels in this ROI between the automated and manual approaches to ROI analysis. Task interactions, however, were consistent across ROI analysis approaches. These findings support the use of automated approaches to ROI analysis in studies of lesioned brains, provided they employ a task interaction design. PMID:26441816

  6. Alcohol Intake and Risk of Thyroid Cancer: A Meta-Analysis of Observational Studies

    PubMed Central

    Hong, Seung-Hee; Myung, Seung-Kwon; Kim, Hyeon Suk

    2017-01-01

    Purpose The purpose of this study was to assess whether alcohol intake is associated with the risk of thyroid cancer by a meta-analysis of observational studies. Materials and Methods We searched PubMed and EMBASE in June of 2015 to locate eligible studies. We included observational studies such as cross-sectional studies, case-control studies, and cohort studies reporting odd ratios (ORs) or relative risk (RRs) with 95% confidence intervals (CIs). Results We included 33 observational studies with two cross-sectional studies, 20 case-controls studies, and 11 cohort studies, which involved a total of 7,725 thyroid cancer patients and 3,113,679 participants without thyroid cancer in the final analysis. In the fixed-effect model meta-analysis of all 33 studies, we found that alcohol intake was consistently associated with a decreased risk of thyroid cancer (OR or RR, 0.74; 95% CI, 0.67 to 0.83; I2=38.6%). In the subgroup meta-analysis by type of study, alcohol intake also decreased the risk of thyroid cancer in both case-control studies (OR, 0.77; 95% CI, 0.65 to 0.92; I2=29.5%; n=20) and cohort studies (RR, 0.70; 95% CI, 0.60 to 0.82; I2=0%; n=11). Moreover, subgroup meta-analyses by type of thyroid cancer, gender, amount of alcohol consumed, and methodological quality of study showed that alcohol intake was significantly associated with a decreased risk of thyroid cancer. Conclusion The current meta-analysis of observational studies found that, unlike most of other types of cancer, alcohol intake decreased the risk of thyroid cancer. PMID:27456949

  7. Beyond Nature versus Nurture: DF Analysis of Nonshared Influences on Problem Behaviors.

    ERIC Educational Resources Information Center

    Rodgers, Joseph Lee; And Others

    1994-01-01

    Two studies of twin, sibling, and cousin pairs among children attempted to extend a model, called DF analysis, which separates hereditary and shared environmental influences. First study supported the validity of DF analysis applied to kinship height and weight data. The second study showed that spanking, reading, and quality of home environment…

  8. The Training of Music Teachers in Colombia: A Descriptive Analysis

    ERIC Educational Resources Information Center

    Nayibe Cárdenas Soler, Ruth; Lorenzo Quiles, Oswaldo; Hargreaves, David J.

    2015-01-01

    This study is an evaluative analysis of 13 Music Education programs in Colombia that provide training for secondary school music teachers for 6th to 11th grade in the Colombian education system. The study utilized an analysis matrix from the International Research Project ALFA II-0448-A, which developed a similar study with Latin American and…

  9. Methods for the Joint Meta-Analysis of Multiple Tests

    ERIC Educational Resources Information Center

    Trikalinos, Thomas A.; Hoaglin, David C.; Small, Kevin M.; Terrin, Norma; Schmid, Christopher H.

    2014-01-01

    Existing methods for meta-analysis of diagnostic test accuracy focus primarily on a single index test. We propose models for the joint meta-analysis of studies comparing multiple index tests on the same participants in paired designs. These models respect the grouping of data by studies, account for the within-study correlation between the tests'…

  10. Atmospheric Transformation of Volatile Organic Compounds

    DTIC Science & Technology

    2008-03-01

    Study Analysis Reactant mixtures and standards from product identification experiments were sampled by exposing a 100% polydimethylsiloxane solid...later using the DNPH derivatization method described above and confirmed against a commercial standard. HPLC analysis of the DNPH cartridges also...reaction mixture for a combined total photolysis time ofapproximately 50 seconds. 2.3. Kinetic Study Analysis Samples from kinetic studies were

  11. Comprehension-Based versus Production-Based Grammar Instruction: A Meta-Analysis of Comparative Studies

    ERIC Educational Resources Information Center

    Shintani, Natsuko; Li, Shaofeng; Ellis, Rod

    2013-01-01

    This article reports a meta-analysis of studies that investigated the relative effectiveness of comprehension-based instruction (CBI) and production-based instruction (PBI). The meta-analysis only included studies that featured a direct comparison of CBI and PBI in order to ensure methodological and statistical robustness. A total of 35 research…

  12. Reviewing the Research on Mail Survey Response Rates: Meta-Analysis.

    ERIC Educational Resources Information Center

    Green, Kathy E.; Hutchinson, Susan R.

    Meta-analysis, a way of cumulating the results of research studies, focuses on the magnitudes of effect sizes and seeks to explain effects through study characteristics. This meta-analysis used the methods developed by G. V. Glass to summarize the research on mail survey response rate manipulations. A narrative review using the same studies set…

  13. Conjoint Analysis of Study Abroad Preferences: Key Attributes, Segments and Implications for Increasing Student Participation

    ERIC Educational Resources Information Center

    Garver, Michael S.; Divine, Richard L.

    2008-01-01

    An adaptive conjoint analysis was performed on the study abroad preferences of a sample of undergraduate college students. The results indicate that trip location, cost, and time spent abroad are the three most important determinants of student preference for different study abroad trip scenarios. The analysis also uncovered four different study…

  14. Progressing from Identification and Functional Analysis of Precursor Behavior to Treatment of Self-Injurious Behavior

    ERIC Educational Resources Information Center

    Dracobly, Joseph D.; Smith, Richard G.

    2012-01-01

    This multiple-study experiment evaluated the utility of assessing and treating severe self-injurious behavior (SIB) based on the outcomes of a functional analysis of precursor behavior. In Study 1, a precursor to SIB was identified using descriptive assessment and conditional probability analyses. In Study 2, a functional analysis of precursor…

  15. The Analysis of a Murder, a Case Study

    ERIC Educational Resources Information Center

    Dinan, Frank J.; Szczepankiewicz, Steven H.; Carnaham, Melinda; Colvin, Michael T.

    2007-01-01

    The analysis of a Murder case study can be used in general chemistry or nonscience major chemistry courses to teach data handling and analysis in a non-laboratory context. This case study will help students to respond more enthusiastically and with more interest to a set of material placed before them related to a real case rather than…

  16. Statistical Considerations of Food Allergy Prevention Studies.

    PubMed

    Bahnson, Henry T; du Toit, George; Lack, Gideon

    Clinical studies to prevent the development of food allergy have recently helped reshape public policy recommendations on the early introduction of allergenic foods. These trials are also prompting new research, and it is therefore important to address the unique design and analysis challenges of prevention trials. We highlight statistical concepts and give recommendations that clinical researchers may wish to adopt when designing future study protocols and analysis plans for prevention studies. Topics include selecting a study sample, addressing internal and external validity, improving statistical power, choosing alpha and beta, analysis innovations to address dilution effects, and analysis methods to deal with poor compliance, dropout, and missing data. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Level of Analysis in the Perception of Ongoing Instruction: An Exploratory Study.

    ERIC Educational Resources Information Center

    Koopman, Cheryl; Newtson, Darren

    1981-01-01

    Instructional variables were manipulated to determine whether they influence the level of perceptual analysis. The relationships of perceptual analysis to concept learning and evaluations of the instructors were also examined in the study. (Author/GK)

  18. How Can Visual Analytics Assist Investigative Analysis? Design Implications from an Evaluation.

    PubMed

    Youn-Ah Kang; Görg, Carsten; Stasko, John

    2011-05-01

    Despite the growing number of systems providing visual analytic support for investigative analysis, few empirical studies of the potential benefits of such systems have been conducted, particularly controlled, comparative evaluations. Determining how such systems foster insight and sensemaking is important for their continued growth and study, however. Furthermore, studies that identify how people use such systems and why they benefit (or not) can help inform the design of new systems in this area. We conducted an evaluation of the visual analytics system Jigsaw employed in a small investigative sensemaking exercise, and compared its use to three other more traditional methods of analysis. Sixteen participants performed a simulated intelligence analysis task under one of the four conditions. Experimental results suggest that Jigsaw assisted participants to analyze the data and identify an embedded threat. We describe different analysis strategies used by study participants and how computational support (or the lack thereof) influenced the strategies. We then illustrate several characteristics of the sensemaking process identified in the study and provide design implications for investigative analysis tools based thereon. We conclude with recommendations on metrics and techniques for evaluating visual analytics systems for investigative analysis.

  19. Thermal Analysis Study of Antihypertensive Drugs Telmisartan and Cilazapril

    PubMed Central

    Saber, Refaat Ahmed; Attia, Ali Kamal; Salem, Waheed Mohamed

    2014-01-01

    Purpose: The aim of the present work is to study the thermal analysis of telmisartan and cilazapril. Methods: Thermogravimetry (TGA), derivative thermogravimetry (DTG) and differential thermal analysis (DTA) were used through the work to achieve the thermal analysis study of some antihypertensive drugs, telmisartan and cilazapril. Results: The results led to thermal stability data and also to the interpretation concerning the thermal decomposition. Thermogravimetry data allowed determination of the kinetic parameters such as, activation energy and frequency factor. Conclusion: The simplicity, speed and low operational costs of thermal analysis justify its application in the quality control of pharmaceutical compounds for medications. PMID:24754013

  20. Blood volume analysis: a new technique and new clinical interest reinvigorate a classic study.

    PubMed

    Manzone, Timothy A; Dam, Hung Q; Soltis, Daniel; Sagar, Vidya V

    2007-06-01

    Blood volume studies using the indicator dilution technique and radioactive tracers have been performed in nuclear medicine departments for over 50 y. A nuclear medicine study is the gold standard for blood volume measurement, but the classic dual-isotope blood volume study is time-consuming and can be prone to technical errors. Moreover, a lack of normal values and a rubric for interpretation made volume status measurement of limited interest to most clinicians other than some hematologists. A new semiautomated system for blood volume analysis is now available and provides highly accurate results for blood volume analysis within only 90 min. The availability of rapid, accurate blood volume analysis has brought about a surge of clinical interest in using blood volume data for clinical management. Blood volume analysis, long a low-volume nuclear medicine study all but abandoned in some laboratories, is poised to enter the clinical mainstream. This article will first present the fundamental principles of fluid balance and the clinical means of volume status assessment. We will then review the indicator dilution technique and how it is used in nuclear medicine blood volume studies. We will present an overview of the new semiautomated blood volume analysis technique, showing how the study is done, how it works, what results are provided, and how those results are interpreted. Finally, we will look at some of the emerging areas in which data from blood volume analysis can improve patient care. The reader will gain an understanding of the principles underlying blood volume assessment, know how current nuclear medicine blood volume analysis studies are performed, and appreciate their potential clinical impact.

  1. Psychological interventions for psychogenic non-epileptic seizures: A meta-analysis.

    PubMed

    Carlson, Perri; Nicholson Perry, Kathryn

    2017-02-01

    The aim of this meta-analysis is to evaluate and synthesize the available evidence from the previous 20 years regarding the utility of psychological interventions in the management of psychogenic non-epileptic seizures (PNES). Studies were retrieved from MEDLINE via OvidSP and PsychINFO. Selection criteria included controlled and before-after non-controlled studies including case series, using seizure frequency as an outcome measurement. Studies were required to assess one or more types of psychological intervention for the treatment of PNES in adults. Data from 13 eligible studies was pooled to examine the effectiveness of psychological interventions in treating PNES on two primary outcomes: seizure reduction of 50% or more and seizure freedom. A meta-analysis was conducted with data extracted from 228 participants with PNES. Interventions reviewed in the analysis included CBT, psychodynamic therapy, paradoxical intention therapy, mindfulness and psychoeducation and eclectic interventions. Meta-analysis synthesized data from 13 studies with a total of 228 participants with PNES, of varied gender and age. Results showed 47% of people with PNES are seizure free upon completion of a psychological intervention. Additional meta-analysis synthesized data from 10 studies with a total of 137 participants with PNES. This analysis found 82% of people with PNES who complete psychological treatment experience a reduction in seizures of at least 50%. The studies identified for this analysis were diverse in nature and quality. The findings highlight the potential for psychological interventions as a favorable alternative to the current lack of treatment options offered to people with PNES. Copyright © 2016 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  2. The Tongue and Quill

    DTIC Science & Technology

    2004-08-01

    ethnography , phenomenological study , grounded theory study and content analysis. THE HISTORICAL METHOD Methods I. Qualitative Research Methods ... Phenomenological Study 4. Grounded Theory Study 5. Content Analysis II. Quantitative Research Methods A...A. The Historical Method B. General Qualitative

  3. Pooled solifenacin overactive bladder trial data: Creation, validation and analysis of an integrated database.

    PubMed

    Chapple, Christopher R; Cardozo, Linda; Snijder, Robert; Siddiqui, Emad; Herschorn, Sender

    2016-12-15

    Patient-level data are available for 11 randomized, controlled, Phase III/Phase IV solifenacin clinical trials. Meta-analyses were conducted to interrogate the data, to broaden knowledge about solifenacin and overactive bladder (OAB) in general. Before integrating data, datasets from individual studies were mapped to a single format using methodology developed by the Clinical Data Interchange Standards Consortium (CDISC). Initially, the data structure was harmonized, to ensure identical categorization, using the CDISC Study Data Tabulation Model (SDTM). To allow for patient level meta-analysis, data were integrated and mapped to analysis datasets. Mapping included adding derived and categorical variables and followed standards described as the Analysis Data Model (ADaM). Mapping to both SDTM and ADaM was performed twice by two independent programming teams, results compared, and inconsistencies corrected in the final output. ADaM analysis sets included assignments of patients to the Safety Analysis Set and the Full Analysis Set. There were three analysis groupings: Analysis group 1 (placebo-controlled, monotherapy, fixed-dose studies, n = 3011); Analysis group 2 (placebo-controlled, monotherapy, pooled, fixed- and flexible-dose, n = 5379); Analysis group 3 (all solifenacin monotherapy-treated patients, n = 6539). Treatment groups were: solifenacin 5 mg fixed dose, solifenacin 5/10 mg flexible dose, solifenacin 10 mg fixed dose and overall solifenacin. Patient were similar enough for data pooling to be acceptable. Creating ADaM datasets provided significant information about individual studies and the derivation decisions made in each study; validated ADaM datasets now exist for medical history, efficacy and AEs. Results from these meta-analyses were similar over time.

  4. Study on magnetic circuit of moving magnet linear compressor

    NASA Astrophysics Data System (ADS)

    Xia, Ming; Chen, Xiaoping; Chen, Jun

    2015-05-01

    The moving magnet linear compressors are very popular in the tactical miniature stirling cryocoolers. The magnetic circuit of LFC3600 moving magnet linear compressor, manufactured by Kunming institute of Physics, was studied in this study. Three methods of the analysis theory, numerical calculation and experiment study were applied in the analysis process. The calculated formula of magnetic reluctance and magnetomotive force were given in theoretical analysis model. The magnetic flux density and magnetic flux line were analyzed in numerical analysis model. A testing method was designed to test the magnetic flux density of the linear compressor. When the piston of the motor was in the equilibrium position, the value of the magnetic flux density was at the maximum of 0.27T. The results were almost equal to the ones from numerical analysis.

  5. Stability analysis and trend study of a balloon tethered in a wind, with experimental comparisons

    NASA Technical Reports Server (NTRS)

    Redd, L. T.; Bland, S. R.; Bennett, R. M.

    1973-01-01

    A stability analysis and trend study for a balloon tethered in a steady wind are presented. The linearized, stability-derivative type analysis includes balloon aerodynamics, buoyancy, mass (including apparent mass), and static forces resulting from the tether cable. The analysis has been applied to a balloon 7.64 m in length, and the results are compared with those from tow tests of this balloon. This comparison shows that the analysis gives reasonable predictions for the damping, frequencies, modes of motion, and stability boundaries exhibited by the balloon. A trend study for the 7.64-m balloon was made to illustrate how the stability boundaries are affected by changes in individual stability parameters. The trends indicated in this study may also be applicable to many other tethered-balloon systems.

  6. Projections of Demand for Waterborne Transportation, Ohio River Basin, 1980, 1990, 2000, 2020, 2040. Volume 1. Study Summary.

    DTIC Science & Technology

    1980-12-01

    NOTES 3 19. KEY WORDS (Continue on revere side If n.cessary d Identify by block number) Bulk cargo Market demand analysis Commodity resource inventory...The study included a Commodity Resource Inventory, a Modal Split Analysis and a Market Demand Analysis. The work included investigation and analyses...inventory, a modal split analysis and a market demand analysis. The work included investigation and analyses of the production, transportation, and

  7. Statistical analysis of the national crash severity study data

    DOT National Transportation Integrated Search

    1980-08-01

    This is the Final Report on a two-year statistical analysis of the data collected in the National Crash Severity Study (NCSS). The analysis presented is primarily concerned with the relationship between occupant injury severity and the crash conditio...

  8. Synthesis, Structure And Properties of Electrochemically Active Nanocomposites

    DTIC Science & Technology

    2003-05-01

    milling. Detailed systematic impedance analysis , electronic conductivity measurement and high-resolution electron microscopy studies have shown that...carbon particles determined by TEM analysis . Results of the studies so far have shown that Sn and Si-based nanocomposites appear to be quite promising... Analysis of the As-milled Powders 117 2. Electrochemical Characteristics of Si/SiC Nanocomposites 120 3. Microstructural/Morphological Analysis of

  9. Analysis of Social Cohesion in Health Data by Factor Analysis Method: The Ghanaian Perspective

    ERIC Educational Resources Information Center

    Saeed, Bashiru I. I.; Xicang, Zhao; Musah, A. A. I.; Abdul-Aziz, A. R.; Yawson, Alfred; Karim, Azumah

    2013-01-01

    We investigated the study of the overall social cohesion of Ghanaians. In this study, we considered the paramount interest of the involvement of Ghanaians in their communities, their views of other people and institutions, and their level of interest in both local and national politics. The factor analysis method was employed for analysis using R…

  10. A framework for performing workplace hazard and risk analysis: a participative ergonomics approach.

    PubMed

    Morag, Ido; Luria, Gil

    2013-01-01

    Despite the unanimity among researchers about the centrality of workplace analysis based on participatory ergonomics (PE) as a basis for preventive interventions, there is still little agreement about the necessary of a theoretical framework for providing practical guidance. In an effort to develop a conceptual PE framework, the authors, focusing on 20 studies, found five primary dimensions for characterising an analytical structure: (1) extent of workforce involvement; (2) analysis duration; (3) diversity of reporter role types; (4) scope of analysis and (5) supportive information system for analysis management. An ergonomics analysis carried out in a chemical manufacturing plant serves as a case study for evaluating the proposed framework. The study simultaneously demonstrates the five dimensions and evaluates their feasibility. The study showed that managerial leadership was fundamental to the successful implementation of the analysis; that all job holders should participate in analysing their own workplace and simplified reporting methods contributed to a desirable outcome. This paper seeks to clarify the scope of workplace ergonomics analysis by offering a theoretical and structured framework for providing practical advice and guidance. Essential to successfully implementing the analytical framework are managerial involvement, participation of all job holders and simplified reporting methods.

  11. An evaluation of interrupted and uninterrupted measurement of vocal stereotypy on perceived treatment outcomes.

    PubMed

    Carroll, Regina A; Kodak, Tiffany

    2014-01-01

    The type of procedure used to measure a target behavior may directly influence the perceived treatment outcomes. In the present study, we examined the influence of different data-analysis procedures on the outcomes of two commonly used treatments on the vocal stereotypy of 2 children with an autism spectrum disorder. In Study 1, we compared an interrupted and uninterrupted data-analysis procedure to measure vocal stereotypy during the implementation of response interruption and redirection (RIRD). The results showed that the interrupted data-analysis procedure overestimated the effectiveness of RIRD. In Study 2, we examined the influence of different data-analysis procedures on the interpretation of the relative effects of 2 different treatments for vocal stereotypy. Specifically, we compared interrupted and uninterrupted data-analysis procedures during the implementation of RIRD and noncontingent reinforcement (NCR) as a treatment for vocal stereotypy. The results showed that, as in Study 1, the interrupted data-analysis procedure overestimated the effectiveness of RIRD; however, this effect was not apparent with NCR. These findings suggest that different types of data analysis can influence the perceived success of a treatment. © Society for the Experimental Analysis of Behavior.

  12. Meta-analysis using Dirichlet process.

    PubMed

    Muthukumarana, Saman; Tiwari, Ram C

    2016-02-01

    This article develops a Bayesian approach for meta-analysis using the Dirichlet process. The key aspect of the Dirichlet process in meta-analysis is the ability to assess evidence of statistical heterogeneity or variation in the underlying effects across study while relaxing the distributional assumptions. We assume that the study effects are generated from a Dirichlet process. Under a Dirichlet process model, the study effects parameters have support on a discrete space and enable borrowing of information across studies while facilitating clustering among studies. We illustrate the proposed method by applying it to a dataset on the Program for International Student Assessment on 30 countries. Results from the data analysis, simulation studies, and the log pseudo-marginal likelihood model selection procedure indicate that the Dirichlet process model performs better than conventional alternative methods. © The Author(s) 2012.

  13. Longitudinal analysis of meta-analysis literatures in the database of ISI Web of Science.

    PubMed

    Zhu, Changtai; Jiang, Ting; Cao, Hao; Sun, Wenguang; Chen, Zhong; Liu, Jinming

    2015-01-01

    The meta-analysis is regarded as an important evidence for making scientific decision. The database of ISI Web of Science collected a great number of high quality literatures including meta-analysis literatures. However, it is significant to understand the general characteristics of meta-analysis literatures to outline the perspective of meta-analysis. In this present study, we summarized and clarified some features on these literatures in the database of ISI Web of Science. We retrieved the meta-analysis literatures in the database of ISI Web of Science including SCI-E, SSCI, A&HCI, CPCI-S, CPCI-SSH, CCR-E, and IC. The annual growth rate, literature category, language, funding, index citation, agencies and countries/territories of the meta-analysis literatures were analyzed, respectively. A total of 95,719 records, which account for 0.38% (99% CI: 0.38%-0.39%) of all literatures, were found in the database. From 1997 to 2012, the annual growth rate of meta-analysis literatures was 18.18%. The literatures involved in many categories, languages, fundings, citations, publication agencies, and countries/territories. Interestingly, the index citation frequencies of the meta-analysis were significantly higher than that of other type literatures such as multi-centre study, randomize controlled trial, cohort study, case control study, and cases report (P<0.0001). The increasing numbers, intensively global influence and high citations revealed that the meta-analysis has been becoming more and more prominent in recent years. In future, in order to promote the validity of meta-analysis, the CONSORT and PRISMA standard should be continuously popularized in the field of evidence-based medicine.

  14. [Why evidence-based medicine? 20 years of meta-analysis].

    PubMed

    Ceballos, C; Valdizán, J R; Artal, A; Almárcegui, C; Allepuz, C; García Campayo, J; Fernández Liesa, R; Giraldo, P; Puértolas, T

    2000-10-01

    Meta-analysis, described within evidence-based medicine, has become a frequent issue in recent medical literature. An exhaustive search of reported meta-analysis from any medical specialty is described. Search of papers included in Medline or Embase between 1973-1998. A study of intra and inter-reviewers liability about selection and classification have been performed. A descriptive analysis of the reported papers (frequency tables and graphics) is described, including differences of mean of reported meta-analysis papers by medical specialty and year. 1,518 papers were selected and classified. Most frequently found (45.91%) were: methodology (15.7%), psychiatry (11.79%), cardiology (10.01%) and oncology (8.36%). Inter personal agreement was 0.93 in selecting papers and 0.72 in classifying them. Between 1977-1987 overall mean of reported studies of meta-analysis (1.67 + 4.10) was significatively inferior to the 1988-1998 (49.54 + 56.55) (p < 0.001). Global number of meta-analysis was positively correlated (p < 0.05) with the number of studies about fundamentals and methodology during the study period. The method used to identify meta-analysis reports can be considered to be adequate; however, the agreement in classifying them in medical specialties was inferior. A progressive increase in the number of reported meta-analysis since 1977 can be demonstrated. Specialties with a greater number of meta-analysis published in the literature were: psychiatry, oncology and cardiology. Diffusion of knowledge about fundamentals and methodology of meta-analysis seems to have drawn and increase in performing and reporting this kind of analysis.

  15. Quality Assessment of Urinary Stone Analysis: Results of a Multicenter Study of Laboratories in Europe

    PubMed Central

    Siener, Roswitha; Buchholz, Noor; Daudon, Michel; Hess, Bernhard; Knoll, Thomas; Osther, Palle J.; Reis-Santos, José; Sarica, Kemal; Traxer, Olivier; Trinchieri, Alberto

    2016-01-01

    After stone removal, accurate analysis of urinary stone composition is the most crucial laboratory diagnostic procedure for the treatment and recurrence prevention in the stone-forming patient. The most common techniques for routine analysis of stones are infrared spectroscopy, X-ray diffraction and chemical analysis. The aim of the present study was to assess the quality of urinary stone analysis of laboratories in Europe. Nine laboratories from eight European countries participated in six quality control surveys for urinary calculi analyses of the Reference Institute for Bioanalytics, Bonn, Germany, between 2010 and 2014. Each participant received the same blinded test samples for stone analysis. A total of 24 samples, comprising pure substances and mixtures of two or three components, were analysed. The evaluation of the quality of the laboratory in the present study was based on the attainment of 75% of the maximum total points, i.e. 99 points. The methods of stone analysis used were infrared spectroscopy (n = 7), chemical analysis (n = 1) and X-ray diffraction (n = 1). In the present study only 56% of the laboratories, four using infrared spectroscopy and one using X-ray diffraction, fulfilled the quality requirements. According to the current standard, chemical analysis is considered to be insufficient for stone analysis, whereas infrared spectroscopy or X-ray diffraction is mandatory. However, the poor results of infrared spectroscopy highlight the importance of equipment, reference spectra and qualification of the staff for an accurate analysis of stone composition. Regular quality control is essential in carrying out routine stone analysis. PMID:27248840

  16. Quality Assessment of Urinary Stone Analysis: Results of a Multicenter Study of Laboratories in Europe.

    PubMed

    Siener, Roswitha; Buchholz, Noor; Daudon, Michel; Hess, Bernhard; Knoll, Thomas; Osther, Palle J; Reis-Santos, José; Sarica, Kemal; Traxer, Olivier; Trinchieri, Alberto

    2016-01-01

    After stone removal, accurate analysis of urinary stone composition is the most crucial laboratory diagnostic procedure for the treatment and recurrence prevention in the stone-forming patient. The most common techniques for routine analysis of stones are infrared spectroscopy, X-ray diffraction and chemical analysis. The aim of the present study was to assess the quality of urinary stone analysis of laboratories in Europe. Nine laboratories from eight European countries participated in six quality control surveys for urinary calculi analyses of the Reference Institute for Bioanalytics, Bonn, Germany, between 2010 and 2014. Each participant received the same blinded test samples for stone analysis. A total of 24 samples, comprising pure substances and mixtures of two or three components, were analysed. The evaluation of the quality of the laboratory in the present study was based on the attainment of 75% of the maximum total points, i.e. 99 points. The methods of stone analysis used were infrared spectroscopy (n = 7), chemical analysis (n = 1) and X-ray diffraction (n = 1). In the present study only 56% of the laboratories, four using infrared spectroscopy and one using X-ray diffraction, fulfilled the quality requirements. According to the current standard, chemical analysis is considered to be insufficient for stone analysis, whereas infrared spectroscopy or X-ray diffraction is mandatory. However, the poor results of infrared spectroscopy highlight the importance of equipment, reference spectra and qualification of the staff for an accurate analysis of stone composition. Regular quality control is essential in carrying out routine stone analysis.

  17. What the Tweets Say: A Critical Analysis of Twitter Research in Language Learning from 2009 to 2016

    ERIC Educational Resources Information Center

    Hattem, David; Lomicka, Lara

    2016-01-01

    This study presents an overview and critical analysis of the literature related to Twitter and language learning published from 2009 to 2016. Seventeen studies were selected for inclusion based on a four-phase identification procedure, which helped us to identify published studies that resulted in a content analysis of themes in the articles…

  18. Educational Cost Analysis in Action: Case Studies for Planners -- I.

    ERIC Educational Resources Information Center

    Coombs, Philip H.; Hallak, Jacques

    This document is the first in a series of three documents, which together contains 27 case studies on the uses of cost analysis in educational planning. The case studies have been presented to help planners and administrators see how cost analysis can be used to improve the efficiency of their educational systems, or how to get the best value from…

  19. Educational Cost Analysis in Action: Case Studies for Planners -- III.

    ERIC Educational Resources Information Center

    Coombs, Philip H.; Hallak, Jacques

    This document is the third in a series of three documents, which together contain 27 case studies on the uses of cost analysis in educational planning. The case studies have been presented to help planners and administrators see how cost analysis can be used to improve the efficiency of their educational systems, and to get the best value from…

  20. Emotional Stability as a Condition of Students' Adaptation to Studying in a Higher Educational Institution

    ERIC Educational Resources Information Center

    Serebryakova, Tat'yana A.; Morozova, Lyudmila B.; Kochneva, Elena M.; Zharova, Darya V.; Kostyleva, Elena A.; Kolarkova, Oxana G.

    2016-01-01

    Background/Objectives: The objective of the paper is analysis and description of findings of an empiric study on the issue of social and psychological adaptation of first year students to studying in a higher educational institution. Methods/Statistical analysis: Using the methods of theoretical analysis the paper's authors plan and carry out an…

  1. Weighing the Evidence: A Meta-Analysis of Bilingual Education in Arizona

    ERIC Educational Resources Information Center

    Rolstad, Kellie; Mahoney, Kate S.; Glass, Gene V.

    2005-01-01

    This article reviews the current policy context in the state of Arizona for program options for English language learners and produces a meta-analysis of studies on the effectiveness of bilingual education that have been conducted in the state in or after 1985. The study presents an analysis of a sample of evaluation studies (N = 4), which…

  2. Nonlinear stability and control study of highly maneuverable high performance aircraft, phase 2

    NASA Technical Reports Server (NTRS)

    Mohler, R. R.

    1992-01-01

    Research leading to the development of new nonlinear methodologies for the adaptive control and stability analysis of high angle of attack aircraft such as the F-18 is discussed. The emphasis has been on nonlinear adaptive control, but associated model development, system identification, stability analysis, and simulation were studied in some detail as well. Studies indicated that nonlinear adaptive control can outperform linear adaptive control for rapid maneuvers with large changes in angle of attack. Included here are studies on nonlinear model algorithmic controller design and an analysis of nonlinear system stability using robust stability analysis for linear systems.

  3. A case study in nonconformance and performance trend analysis

    NASA Technical Reports Server (NTRS)

    Maloy, Joseph E.; Newton, Coy P.

    1990-01-01

    As part of NASA's effort to develop an agency-wide approach to trend analysis, a pilot nonconformance and performance trending analysis study was conducted on the Space Shuttle auxiliary power unit (APU). The purpose of the study was to (1) demonstrate that nonconformance analysis can be used to identify repeating failures of a specific item (and the associated failure modes and causes) and (2) determine whether performance parameters could be analyzed and monitored to provide an indication of component or system degradation prior to failure. The nonconformance analysis of the APU did identify repeating component failures, which possibly could be reduced if key performance parameters were monitored and analyzed. The performance-trending analysis verified that the characteristics of hardware parameters can be effective in detecting degradation of hardware performance prior to failure.

  4. Association between tea consumption and osteoporosis: A meta-analysis.

    PubMed

    Sun, Kang; Wang, Le; Ma, Qingping; Cui, Qiaoyun; Lv, Qianru; Zhang, Wenzheng; Li, Xinghui

    2017-12-01

    Previous reports have suggested a potential association of tea consumption with the risk of osteoporosis. As such association is controversial, we conducted a meta-analysis to assess the relationship between tea consumption and osteoporosis. We systematically searched PubMed, EMBASE and WanFang databases until March 30, 2016, using the keywords "tea and osteoporosis," without limits of language. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were derived by using random-effects models throughout the analyses. We conducted the analysis of the statistical heterogeneity using Cochrane I. The funnel plot was used to speculate the publication bias, while the subgroup analysis and multiround elimination method were employed. Our study was based on 17 journal articles, including 2 prospective cohort studies, 4 case-control studies, and 11 cross-sectional studies. In the present study, the total OR of osteoporosis for the highest versus the lowest categories of tea consumption was 0.62 (95% CI, 0.46-0.83), with significant heterogeneity among studies (I = 94%, P < .01). There was, however, no publication bias of the meta-analysis about tea consumption and osteoporosis. Subgroup analysis showed that tea consumption could reduce the risk of osteoporosis in all examined subgroups. In the present study, it can be concluded from the results that tea consumption can reduce the risk of osteoporosis.

  5. The Role of Spatial Analysis in Detecting the Consequence of the Factory Sites : Case Study of Assalaya Factory-Sudan

    NASA Astrophysics Data System (ADS)

    Khair, Amar Sharaf Eldin; Purwanto; RyaSunoko, Henna; Abdullah, Omer Adam

    2018-02-01

    Spatial analysis is considered as one of the most important science for identifying the most appropriate site for industrialization and also to alleviate the environmental ramifications caused by factories. This study aims at analyzing the Assalaya sugarcane factory site by the use of spatial analysis to determine whether it has ramification on the White Nile River. The methodology employed for this study is Global Position System (GPS) to identify the coordinate system of the study phenomena and other relative factors. The study will also make use Geographical Information System (GIS) to implement the spatial analysis. Satellite data (LandsatDem-Digital Elevation Model) will be considered for the study area and factory in identifying the consequences by analyzing the location of the factory through several features such as hydrological, contour line and geological analysis. Data analysis reveals that the factory site is inappropriate and according to observation on the ground it has consequences on the White Nile River. Based on the finding, the study recommended some suggestions to avoid the aftermath of any factory in general. We have to take advantage of this new technological method to aid in selecting most apt locations for industries that will create an ambient environment.

  6. [Methods of a posteriori identification of food patterns in Brazilian children: a systematic review].

    PubMed

    Carvalho, Carolina Abreu de; Fonsêca, Poliana Cristina de Almeida; Nobre, Luciana Neri; Priore, Silvia Eloiza; Franceschini, Sylvia do Carmo Castro

    2016-01-01

    The objective of this study is to provide guidance for identifying dietary patterns using the a posteriori approach, and analyze the methodological aspects of the studies conducted in Brazil that identified the dietary patterns of children. Articles were selected from the Latin American and Caribbean Literature on Health Sciences, Scientific Electronic Library Online and Pubmed databases. The key words were: Dietary pattern; Food pattern; Principal Components Analysis; Factor analysis; Cluster analysis; Reduced rank regression. We included studies that identified dietary patterns of children using the a posteriori approach. Seven studies published between 2007 and 2014 were selected, six of which were cross-sectional and one cohort, Five studies used the food frequency questionnaire for dietary assessment; one used a 24-hour dietary recall and the other a food list. The method of exploratory approach used in most publications was principal components factor analysis, followed by cluster analysis. The sample size of the studies ranged from 232 to 4231, the values of the Kaiser-Meyer-Olkin test from 0.524 to 0.873, and Cronbach's alpha from 0.51 to 0.69. Few Brazilian studies identified dietary patterns of children using the a posteriori approach and principal components factor analysis was the technique most used.

  7. Collection and analysis of 2013-2014 travel time data.

    DOT National Transportation Integrated Search

    2017-07-04

    This report documents the findings of Planning Study 27, Collection and Analysis of 2013-2014 Travel Time Data, which is a continuation of Planning Study 24, Analysis of Historical Travel Time Data. The main scope is to analyze newly acquired link-re...

  8. 40 CFR 761.323 - Sample preparation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROHIBITIONS Self-Implementing Alternative Extraction and Chemical Analysis Procedures for Non-liquid PCB Remediation Waste Samples § 761.323 Sample preparation. (a) The comparison study requires analysis of a... of use in this chemical extraction and chemical analysis comparison study, a person may adjust PCB...

  9. Preliminary Thermal-Mechanical Sizing of Metallic TPS: Process Development and Sensitivity Studies

    NASA Technical Reports Server (NTRS)

    Poteet, Carl C.; Abu-Khajeel, Hasan; Hsu, Su-Yuen

    2002-01-01

    The purpose of this research was to perform sensitivity studies and develop a process to perform thermal and structural analysis and sizing of the latest Metallic Thermal Protection System (TPS) developed at NASA LaRC (Langley Research Center). Metallic TPS is a key technology for reducing the cost of reusable launch vehicles (RLV), offering the combination of increased durability and competitive weights when compared to other systems. Accurate sizing of metallic TPS requires combined thermal and structural analysis. Initial sensitivity studies were conducted using transient one-dimensional finite element thermal analysis to determine the influence of various TPS and analysis parameters on TPS weight. The thermal analysis model was then used in combination with static deflection and failure mode analysis of the sandwich panel outer surface of the TPS to obtain minimum weight TPS configurations at three vehicle stations on the windward centerline of a representative RLV. The coupled nature of the analysis requires an iterative analysis process, which will be described herein. Findings from the sensitivity analysis are reported, along with TPS designs at the three RLV vehicle stations considered.

  10. Primary, Secondary, and Meta-Analysis of Research

    ERIC Educational Resources Information Center

    Glass, Gene V.

    1976-01-01

    Examines data analysis at three levels: analysis of data; secondary analysis is the re-analysis of data for the purpose of answering the original research question with better statistical techniques, or answering new questions with old data; and, meta-analysis refers to the statistical analysis of many analysis results from individual studies for…

  11. Interpreting Meta-Analyses of Genome-Wide Association Studies

    PubMed Central

    Han, Buhm; Eskin, Eleazar

    2012-01-01

    Meta-analysis is an increasingly popular tool for combining multiple genome-wide association studies in a single analysis to identify associations with small effect sizes. The effect sizes between studies in a meta-analysis may differ and these differences, or heterogeneity, can be caused by many factors. If heterogeneity is observed in the results of a meta-analysis, interpreting the cause of heterogeneity is important because the correct interpretation can lead to a better understanding of the disease and a more effective design of a replication study. However, interpreting heterogeneous results is difficult. The standard approach of examining the association p-values of the studies does not effectively predict if the effect exists in each study. In this paper, we propose a framework facilitating the interpretation of the results of a meta-analysis. Our framework is based on a new statistic representing the posterior probability that the effect exists in each study, which is estimated utilizing cross-study information. Simulations and application to the real data show that our framework can effectively segregate the studies predicted to have an effect, the studies predicted to not have an effect, and the ambiguous studies that are underpowered. In addition to helping interpretation, the new framework also allows us to develop a new association testing procedure taking into account the existence of effect. PMID:22396665

  12. Developmental defects of enamel and dental caries in the primary dentition: A systematic review and meta-analysis.

    PubMed

    Costa, Francine S; Silveira, Ethieli R; Pinto, Gabriela S; Nascimento, Gustavo G; Thomson, William Murray; Demarco, Flávio F

    2017-05-01

    This systematic review and meta-analysis evaluated the association between developmental defects of enamel and dental caries in the primary dentition. Electronic searches were performed in PubMed, Web of Knowledge, Scopus and Scielo for the identification of relevant studies. Observational studies that examined the association between developmental defects of enamel and dental caries in the deciduous dentition were included. Additionally, meta-analysis, funnel plots and sensitivity analysis were employed to synthesize the available evidence. Multivariable meta-regression analysis was performed to explore heterogeneity among studies. A total of 318 articles were identified in the electronic searches. Of those, 16 studies were included in the meta-analysis. Pooled estimates revealed that children with developmental defects of enamel had higher odds of having dental caries (OR 3.32; 95%CI 2.41-4.57), with high heterogeneity between studies (I 2 80%). Methodological characteristic of the studies, such as where it was conducted, the examined teeth and the quality of the study explained about 30% of the variability. Concerning type of defect, children with hypoplasia and diffuse opacities had higher odds of having dental caries (OR 4.28; 95%CI 2.24-8.15; OR1.42; 95%CI 1.15-1.76, respectively). This systematic review and meta-analysis demonstrates a clear association between developmental defects of enamel and dental caries in the primary dentition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Game-based digital interventions for depression therapy: a systematic review and meta-analysis.

    PubMed

    Li, Jinhui; Theng, Yin-Leng; Foo, Schubert

    2014-08-01

    The aim of this study was to review the existing literature on game-based digital interventions for depression systematically and examine their effectiveness through a meta-analysis of randomized controlled trials (RCTs). Database searching was conducted using specific search terms and inclusion criteria. A standard meta-analysis was also conducted of available RCT studies with a random effects model. The standard mean difference (Cohen's d) was used to calculate the effect size of each study. Nineteen studies were included in the review, and 10 RCTs (eight studies) were included in the meta-analysis. Four types of game interventions-psycho-education and training, virtual reality exposure therapy, exercising, and entertainment-were identified, with various types of support delivered and populations targeted. The meta-analysis revealed a moderate effect size of the game interventions for depression therapy at posttreatment (d=-0.47 [95% CI -0.69 to -0.24]). A subgroup analysis showed that interventions based on psycho-education and training had a smaller effect than those based on the other forms, and that self-help interventions yielded better outcomes than supported interventions. A higher effect was achieved when a waiting list was used as the control. The review and meta-analysis support the effectiveness of game-based digital interventions for depression. More large-scale, high-quality RCT studies with sufficient long-term data for treatment evaluation are needed.

  14. Game-Based Digital Interventions for Depression Therapy: A Systematic Review and Meta-Analysis

    PubMed Central

    Theng, Yin-Leng; Foo, Schubert

    2014-01-01

    Abstract The aim of this study was to review the existing literature on game-based digital interventions for depression systematically and examine their effectiveness through a meta-analysis of randomized controlled trials (RCTs). Database searching was conducted using specific search terms and inclusion criteria. A standard meta-analysis was also conducted of available RCT studies with a random effects model. The standard mean difference (Cohen's d) was used to calculate the effect size of each study. Nineteen studies were included in the review, and 10 RCTs (eight studies) were included in the meta-analysis. Four types of game interventions—psycho-education and training, virtual reality exposure therapy, exercising, and entertainment—were identified, with various types of support delivered and populations targeted. The meta-analysis revealed a moderate effect size of the game interventions for depression therapy at posttreatment (d=−0.47 [95% CI −0.69 to −0.24]). A subgroup analysis showed that interventions based on psycho-education and training had a smaller effect than those based on the other forms, and that self-help interventions yielded better outcomes than supported interventions. A higher effect was achieved when a waiting list was used as the control. The review and meta-analysis support the effectiveness of game-based digital interventions for depression. More large-scale, high-quality RCT studies with sufficient long-term data for treatment evaluation are needed. PMID:24810933

  15. Alternative Measures of Between-Study Heterogeneity in Meta-Analysis: Reducing the Impact of Outlying Studies

    PubMed Central

    Lin, Lifeng; Chu, Haitao; Hodges, James S.

    2016-01-01

    Summary Meta-analysis has become a widely used tool to combine results from independent studies. The collected studies are homogeneous if they share a common underlying true effect size; otherwise, they are heterogeneous. A fixed-effect model is customarily used when the studies are deemed homogeneous, while a random-effects model is used for heterogeneous studies. Assessing heterogeneity in meta-analysis is critical for model selection and decision making. Ideally, if heterogeneity is present, it should permeate the entire collection of studies, instead of being limited to a small number of outlying studies. Outliers can have great impact on conventional measures of heterogeneity and the conclusions of a meta-analysis. However, no widely accepted guidelines exist for handling outliers. This article proposes several new heterogeneity measures. In the presence of outliers, the proposed measures are less affected than the conventional ones. The performance of the proposed and conventional heterogeneity measures are compared theoretically, by studying their asymptotic properties, and empirically, using simulations and case studies. PMID:27167143

  16. Macroeconomics of Natural Disasters: Strengths and Weaknesses of Meta-Analysis Versus Review of Literature.

    PubMed

    A G van Bergeijk, Peter; Lazzaroni, Sara

    2015-06-01

    We use the case of the macroeconomic impact of natural disasters to analyze strengths and weaknesses of meta-analysis in an emerging research field. Macroeconomists have published on this issue since 2002 (we identified 60 studies to date). The results of the studies are contradictory and therefore the need to synthesize the available research is evident. Meta-analysis is a useful method in this field. An important aim of our article is to show how one can use the identified methodological characteristics to better understand the robustness and importance of new findings. To provide a comparative perspective, we contrast our meta-analysis and its findings with the major influential research synthesis in the field: the IPCC's 2012 special report Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation. We show that the IPCC could have been more confident about the negative economic impact of disasters and more transparent on inclusion and qualification of studies, if it had been complemented by a meta-analysis. Our meta-analysis shows that, controlling for modeling strategies and data set, the impact of disasters is significantly negative. The evidence is strongest for direct costs studies where we see no difference between our larger sample and the studies included in the IPCC report. Direct cost studies and indirect cost studies differ significantly, both in terms of the confidence that can be attached to a negative impact of natural disasters and in terms of the sources of heterogeneity of the findings reported in the primary studies. © 2015 Society for Risk Analysis.

  17. The Derivation of Job Compensation Index Values from the Position Analysis Questionnaire (PAQ). Report No. 6.

    ERIC Educational Resources Information Center

    McCormick, Ernest J.; And Others

    The study deals with the job component method of establishing compensation rates. The basic job analysis questionnaire used in the study was the Position Analysis Questionnaire (PAQ) (Form B). On the basis of a principal components analysis of PAQ data for a large sample (2,688) of jobs, a number of principal components (job dimensions) were…

  18. The Application of Structured Job Analysis Information Based on the Position Analysis Questionnaire (PAQ). Final Report No. 9.

    ERIC Educational Resources Information Center

    McCormick, Ernest J.

    The Position Analysis Questionnaire (PAQ) is a job analysis instrument consisting of 187 job elements organized into six divisions. The PAQ was used in the eight studies summarized in this final report. The studies were: (1) ratings of the attribute requirements of PAQ job elements, (2) a series of principal components analyses of these attribute…

  19. Computer-Assisted Analysis of Near-Bottom Photos for Benthic Habitat Studies

    DTIC Science & Technology

    2006-09-01

    navigated survey platform greatly increases the efficiency of image analysis and provides new insight about the relationships between benthic organisms...increase in the efficiency of image analysis for benthic habitat studies, and provides the opportunity to assess small scale spatial distribution of

  20. Investigating Prospective Social Studies Teachers? Perceptions of European Union through Metaphor Analysis

    ERIC Educational Resources Information Center

    Akgün, Ismail Hakan

    2017-01-01

    The purpose of this study is to investigate metaphors developed by social studies teacher candidates about the European Union. 185 second, third and fourth year social studies teacher candidates participated in the study. This study was designed as a phenomenological study and mataphor analysis was conducted. At the end of the study, the students…

  1. Lucid dreaming incidence: A quality effects meta-analysis of 50years of research.

    PubMed

    Saunders, David T; Roe, Chris A; Smith, Graham; Clegg, Helen

    2016-07-01

    We report a quality effects meta-analysis on studies from the period 1966-2016 measuring either (a) lucid dreaming prevalence (one or more lucid dreams in a lifetime); (b) frequent lucid dreaming (one or more lucid dreams in a month) or both. A quality effects meta-analysis allows for the minimisation of the influence of study methodological quality on overall model estimates. Following sensitivity analysis, a heterogeneous lucid dreaming prevalence data set of 34 studies yielded a mean estimate of 55%, 95% C. I. [49%, 62%] for which moderator analysis showed no systematic bias for suspected sources of variability. A heterogeneous lucid dreaming frequency data set of 25 studies yielded a mean estimate of 23%, 95% C. I. [20%, 25%], moderator analysis revealed no suspected sources of variability. These findings are consistent with earlier estimates of lucid dreaming prevalence and frequent lucid dreaming in the population but are based on more robust evidence. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Increased Consumption of Fruit and Vegetables Is Related to a Reduced Risk of Cognitive Impairment and Dementia: Meta-Analysis

    PubMed Central

    Jiang, Xian; Huang, Jiang; Song, Daqiang; Deng, Ru; Wei, Jicheng; Zhang, Zhuo

    2017-01-01

    Background: Increased consumption of fruit and vegetables has been shown to be associated with a reduced risk of cognitive impairment and dementia in many epidemiological studies. The purpose of this study was to assess the strength of this association in a meta-analysis. Methods: We identified relevant studies by searching Medline, Embase, and Cochrane Library electronic databases (from 1970 to January 2016). Study were included if they reported relative risks and corresponding 95% confidence intervals (CIs) of cognitive impairment and dementia with respect to frequency of fruit and vegetable intake. Results: Nine studies (five cohort studies and four cross-sectional studies) met the inclusion criteria and were included in the meta-analysis. There were a total of 31,104 participants and 4,583 incident cases of cognitive impairment and dementia. The meta-analysis showed that an increased consumption of fruit and vegetables was associated with a significant reduction in the risk of cognitive impairment and dementia (OR = 0.80, 95% CI 0.71–0.89). Subgroup analysis indicated this inverse association was only found among participants with mean age over 65 years and combined sexes. Dose–response meta-analysis showed that an increment of 100 g per day of fruit and vegetable consumption was related to an approximately 13% (OR = 0.87, 95% CI 0.77–0.99) reduction in cognitive impairment and dementia risk. There was no potential publication bias in the meta-analysis and the dose–response meta-analysis. Conclusion: The increased consumption of fruit and vegetables is associated with a reduced risk of cognitive impairment and dementia. PMID:28223933

  3. Noninvasive Electromagnetic Source Imaging and Granger Causality Analysis: An Electrophysiological Connectome (eConnectome) Approach

    PubMed Central

    Sohrabpour, Abbas; Ye, Shuai; Worrell, Gregory A.; Zhang, Wenbo

    2016-01-01

    Objective Combined source imaging techniques and directional connectivity analysis can provide useful information about the underlying brain networks in a non-invasive fashion. Source imaging techniques have been used successfully to either determine the source of activity or to extract source time-courses for Granger causality analysis, previously. In this work, we utilize source imaging algorithms to both find the network nodes (regions of interest) and then extract the activation time series for further Granger causality analysis. The aim of this work is to find network nodes objectively from noninvasive electromagnetic signals, extract activation time-courses and apply Granger analysis on the extracted series to study brain networks under realistic conditions. Methods Source imaging methods are used to identify network nodes and extract time-courses and then Granger causality analysis is applied to delineate the directional functional connectivity of underlying brain networks. Computer simulations studies where the underlying network (nodes and connectivity pattern) is known were performed; additionally, this approach has been evaluated in partial epilepsy patients to study epilepsy networks from inter-ictal and ictal signals recorded by EEG and/or MEG. Results Localization errors of network nodes are less than 5 mm and normalized connectivity errors of ~20% in estimating underlying brain networks in simulation studies. Additionally, two focal epilepsy patients were studied and the identified nodes driving the epileptic network were concordant with clinical findings from intracranial recordings or surgical resection. Conclusion Our study indicates that combined source imaging algorithms with Granger causality analysis can identify underlying networks precisely (both in terms of network nodes location and internodal connectivity). Significance The combined source imaging and Granger analysis technique is an effective tool for studying normal or pathological brain conditions. PMID:27740473

  4. Noninvasive Electromagnetic Source Imaging and Granger Causality Analysis: An Electrophysiological Connectome (eConnectome) Approach.

    PubMed

    Sohrabpour, Abbas; Ye, Shuai; Worrell, Gregory A; Zhang, Wenbo; He, Bin

    2016-12-01

    Combined source-imaging techniques and directional connectivity analysis can provide useful information about the underlying brain networks in a noninvasive fashion. Source-imaging techniques have been used successfully to either determine the source of activity or to extract source time-courses for Granger causality analysis, previously. In this work, we utilize source-imaging algorithms to both find the network nodes [regions of interest (ROI)] and then extract the activation time series for further Granger causality analysis. The aim of this work is to find network nodes objectively from noninvasive electromagnetic signals, extract activation time-courses, and apply Granger analysis on the extracted series to study brain networks under realistic conditions. Source-imaging methods are used to identify network nodes and extract time-courses and then Granger causality analysis is applied to delineate the directional functional connectivity of underlying brain networks. Computer simulations studies where the underlying network (nodes and connectivity pattern) is known were performed; additionally, this approach has been evaluated in partial epilepsy patients to study epilepsy networks from interictal and ictal signals recorded by EEG and/or Magnetoencephalography (MEG). Localization errors of network nodes are less than 5 mm and normalized connectivity errors of ∼20% in estimating underlying brain networks in simulation studies. Additionally, two focal epilepsy patients were studied and the identified nodes driving the epileptic network were concordant with clinical findings from intracranial recordings or surgical resection. Our study indicates that combined source-imaging algorithms with Granger causality analysis can identify underlying networks precisely (both in terms of network nodes location and internodal connectivity). The combined source imaging and Granger analysis technique is an effective tool for studying normal or pathological brain conditions.

  5. Adolescent judgment of sexual content on television: implications for future content analysis research.

    PubMed

    Manganello, Jennifer A; Henderson, Vani R; Jordan, Amy; Trentacoste, Nicole; Martin, Suzanne; Hennessy, Michael; Fishbein, Martin

    2010-07-01

    Many studies of sexual messages in media utilize content analysis methods. At times, this research assumes that researchers and trained coders using content analysis methods and the intended audience view and interpret media content similarly. This article compares adolescents' perceptions of the presence or absence of sexual content on television to those of researchers using three different coding schemes. Results from this formative research study suggest that participants and researchers are most likely to agree with content categories assessing manifest content, and that differences exist among adolescents who view sexual messages on television. Researchers using content analysis methods to examine sexual content in media and media effects on sexual behavior should consider identifying how audience characteristics may affect interpretation of content and account for audience perspectives in content analysis study protocols when appropriate for study goals.

  6. The wavelet analysis for the assessment of microvascular function with the laser Doppler fluxmetry over the last 20 years. Looking for hidden informations.

    PubMed

    Martini, Romeo; Bagno, Andrea

    2018-04-14

    The wavelet analysis has been applied to the Laser Doppler Fluxmetry for assessing the frequency spectrum of the flowmotion to study the microvascular function waves.Although the application of wavelet analysis has allowed a detailed evaluation of the microvascular function, its use does not seem to be yet widespread over the last two decades.Aiming to improve the diffusion of this methodology, we herein present a systematic review of the literature about the application of the wavelet analysis to the laser Doppler fluxmetry signal. A computer research has been performed on PubMed and Scopus databases from January 1990 to December 2017. The used terms for the investigation have been "wavelet analysis", "wavelet transform analysis", "Morlet wavelet transform" along with the terms "laser Doppler", "laserdoppler" and/or "flowmetry" or "fluxmetry". One hundred and eighteen studies have been found. After the scrutiny, 97 studies reporting data on humans have been selected. Fifty-three studies, 54.0% (95% CI 44.2-63.6) pooled rate, have been performed on 892 healthy subjects and 44, 45,9 % (95% CI 36.3-55.7%) pooled rate have been performed on 1679 patients. No significant difference has been found between the two groups (p 0,81). On average, the number of studies published each year was 4.8 (95% CI 3.4-6.2). The trend of studies production has increased significantly from 1998 to 2017, (p 0.0006). But only the studies on patients have shown a significant increase trend along the years (p 0.0003), than the studies on healthy subjects (p 0.09).In conclusion, this review highlights that despite being a promising and interesting methodology for the study of the microcirculatory function, the wavelet analysis has remained still neglected.

  7. Analysis of Art House Media Texts Use during Media Studies in the Student Audience (Alain Robbe-Grillet Movies Case Study)

    ERIC Educational Resources Information Center

    Fedorov, Alexander

    2012-01-01

    The study of media culture and virtual world requires knowledge and skills of the analysis of media texts of different levels of complexity. In this sense, the cinematic legacy of the great French writer, screenwriter and filmmaker Alain Robbe-Grillet (1922-2008) gives productive opportunities for the analysis of works of the elite media culture…

  8. Serum vitamin D levels in relation to schizophrenia: a systematic review and meta-analysis of observational studies.

    PubMed

    Valipour, Ghazaleh; Saneei, Parvane; Esmaillzadeh, Ahmad

    2014-10-01

    Although several observational studies have investigated the association between vitamin D status and schizophrenia, we are aware of no comprehensive meta-analysis in this regard. We aimed to conduct a systematic review and a meta-analysis of observational studies to summarize the available data on the association between serum vitamin D levels and schizophrenia. A systematic research on all published articles until October 2013 was conducted in PubMed, ISI (Web of science), SCOPUS, and Google Scholar. All observational studies that had measured serum vitamin D levels in schizophrenic patients were included in the systematic review. After considering exclusion criteria, we had 19 studies for the systematic review that were included in three separate meta-analyses: 1) a meta-analysis on mean levels of 25-hydroxyvitamin D [25(OH)D] (n = 13); 2) a meta-analysis on the prevalence of vitamin D deficiency (n = 8); 3) a meta-analysis on odds ratios (n = 8). Findings from a meta-analysis on means revealed that the overall mean difference in serum 25(OH)D levels between schizophrenic patients and control participants was -5.91 ng/mL [95% confidence interval (CI) -10.68, -1.14]. Subgroup analyses based on study design, the patient's hospitalization status, study quality, and study location did not explain between-study heterogeneity; however, type of biomarker assessed [25-hydroxyvitamin D3 vs 25-hydroxyvitamin D (D2 & D3)] could account for some degree of heterogeneity. RESULTS from the meta-analysis on the prevalence of vitamin D deficiency indicated that the overall prevalence of vitamin D deficiency in schizophrenic patients was 65.3% (95% CI 46.4%-84.2%). Findings from the meta-analysis on odds ratios indicated that vitamin D-deficient persons were 2.16 times (95% CI 1.32, 3.56) more likely to have schizophrenia than those with vitamin D sufficiency. No evidence of heterogeneity was detected. We found a strong association between vitamin D deficiency and schizophrenia. However, randomized clinical trials are required to confirm our findings.

  9. Methodology Series Module 6: Systematic Reviews and Meta-analysis

    PubMed Central

    Setia, Maninder Singh

    2016-01-01

    Systematic reviews and meta-analysis have become an important of biomedical literature, and they provide the “highest level of evidence” for various clinical questions. There are a lot of studies – sometimes with contradictory conclusions – on a particular topic in literature. Hence, as a clinician, which results will you believe? What will you tell your patient? Which drug is better? A systematic review or a meta-analysis may help us answer these questions. In addition, it may also help us understand the quality of the articles in literature or the type of studies that have been conducted and published (example, randomized trials or observational studies). The first step it to identify a research question for systematic review or meta-analysis. The next step is to identify the articles that will be included in the study. This will be done by searching various databases; it is important that the researcher should search for articles in more than one database. It will also be useful to form a group of researchers and statisticians that have expertise in conducting systematic reviews and meta-analysis before initiating them. We strongly encourage the readers to register their proposed review/meta-analysis with PROSPERO. Finally, these studies should be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis checklist. PMID:27904176

  10. Methodology Series Module 6: Systematic Reviews and Meta-analysis.

    PubMed

    Setia, Maninder Singh

    2016-01-01

    Systematic reviews and meta-analysis have become an important of biomedical literature, and they provide the "highest level of evidence" for various clinical questions. There are a lot of studies - sometimes with contradictory conclusions - on a particular topic in literature. Hence, as a clinician, which results will you believe? What will you tell your patient? Which drug is better? A systematic review or a meta-analysis may help us answer these questions. In addition, it may also help us understand the quality of the articles in literature or the type of studies that have been conducted and published (example, randomized trials or observational studies). The first step it to identify a research question for systematic review or meta-analysis. The next step is to identify the articles that will be included in the study. This will be done by searching various databases; it is important that the researcher should search for articles in more than one database. It will also be useful to form a group of researchers and statisticians that have expertise in conducting systematic reviews and meta-analysis before initiating them. We strongly encourage the readers to register their proposed review/meta-analysis with PROSPERO. Finally, these studies should be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis checklist.

  11. Mobile phone use and risk of tumors: a meta-analysis.

    PubMed

    Myung, Seung-Kwon; Ju, Woong; McDonnell, Diana D; Lee, Yeon Ji; Kazinets, Gene; Cheng, Chih-Tao; Moskowitz, Joel M

    2009-11-20

    Case-control studies have reported inconsistent findings regarding the association between mobile phone use and tumor risk. We investigated these associations using a meta-analysis. We searched MEDLINE (PubMed), EMBASE, and the Cochrane Library in August 2008. Two evaluators independently reviewed and selected articles based on predetermined selection criteria. Of 465 articles meeting our initial criteria, 23 case-control studies, which involved 37,916 participants (12,344 patient cases and 25,572 controls), were included in the final analyses. Compared with never or rarely having used a mobile phone, the odds ratio for overall use was 0.98 for malignant and benign tumors (95% CI, 0.89 to 1.07) in a random-effects meta-analysis of all 23 studies. However, a significant positive association (harmful effect) was observed in a random-effects meta-analysis of eight studies using blinding, whereas a significant negative association (protective effect) was observed in a fixed-effects meta-analysis of 15 studies not using blinding. Mobile phone use of 10 years or longer was associated with a risk of tumors in 13 studies reporting this association (odds ratio = 1.18; 95% CI, 1.04 to 1.34). Further, these findings were also observed in the subgroup analyses by methodologic quality of study. Blinding and methodologic quality of study were strongly associated with the research group. The current study found that there is possible evidence linking mobile phone use to an increased risk of tumors from a meta-analysis of low-biased case-control studies. Prospective cohort studies providing a higher level of evidence are needed.

  12. Cluster headache and the hypocretin receptor 2 reconsidered: a genetic association study and meta-analysis.

    PubMed

    Weller, Claudia M; Wilbrink, Leopoldine A; Houwing-Duistermaat, Jeanine J; Koelewijn, Stephany C; Vijfhuizen, Lisanne S; Haan, Joost; Ferrari, Michel D; Terwindt, Gisela M; van den Maagdenberg, Arn M J M; de Vries, Boukje

    2015-08-01

    Cluster headache is a severe neurological disorder with a complex genetic background. A missense single nucleotide polymorphism (rs2653349; p.Ile308Val) in the HCRTR2 gene that encodes the hypocretin receptor 2 is the only genetic factor that is reported to be associated with cluster headache in different studies. However, as there are conflicting results between studies, we re-evaluated its role in cluster headache. We performed a genetic association analysis for rs2653349 in our large Leiden University Cluster headache Analysis (LUCA) program study population. Systematic selection of the literature yielded three additional studies comprising five study populations, which were included in our meta-analysis. Data were extracted according to predefined criteria. A total of 575 cluster headache patients from our LUCA study and 874 controls were genotyped for HCRTR2 SNP rs2653349 but no significant association with cluster headache was found (odds ratio 0.91 (95% confidence intervals 0.75-1.10), p = 0.319). In contrast, the meta-analysis that included in total 1167 cluster headache cases and 1618 controls from the six study populations, which were part of four different studies, showed association of the single nucleotide polymorphism with cluster headache (random effect odds ratio 0.69 (95% confidence intervals 0.53-0.90), p = 0.006). The association became weaker, as the odds ratio increased to 0.80, when the meta-analysis was repeated without the initial single South European study with the largest effect size. Although we did not find evidence for association of rs2653349 in our LUCA study, which is the largest investigated study population thus far, our meta-analysis provides genetic evidence for a role of HCRTR2 in cluster headache. Regardless, we feel that the association should be interpreted with caution as meta-analyses with individual populations that have limited power have diminished validity. © International Headache Society 2014.

  13. Observational studies using propensity score analysis underestimated the effect sizes in critical care medicine.

    PubMed

    Zhang, Zhongheng; Ni, Hongying; Xu, Xiao

    2014-08-01

    Propensity score (PS) analysis has been increasingly used in critical care medicine; however, its validation has not been systematically investigated. The present study aimed to compare effect sizes in PS-based observational studies vs. randomized controlled trials (RCTs) (or meta-analysis of RCTs). Critical care observational studies using PS were systematically searched in PubMed from inception to April 2013. Identified PS-based studies were matched to one or more RCTs in terms of population, intervention, comparison, and outcome. The effect sizes of experimental treatments were compared for PS-based studies vs. RCTs (or meta-analysis of RCTs) with sign test. Furthermore, ratio of odds ratio (ROR) was calculated from the interaction term of treatment × study type in a logistic regression model. A ROR < 1 indicates greater benefit for experimental treatment in RCTs compared with PS-based studies. RORs of each comparison were pooled by using meta-analytic approach with random-effects model. A total of 20 PS-based studies were identified and matched to RCTs. Twelve of the 20 comparisons showed greater beneficial effect for experimental treatment in RCTs than that in PS-based studies (sign test P = 0.503). The difference was statistically significant in four comparisons. ROR can be calculated from 13 comparisons, of which four showed significantly greater beneficial effect for experimental treatment in RCTs. The pooled ROR was 0.71 (95% CI: 0.63, 0.79; P = 0.002), suggesting that RCTs (or meta-analysis of RCTs) were more likely to report beneficial effect for the experimental treatment than PS-based studies. The result remained unchanged in sensitivity analysis and meta-regression. In critical care literature, PS-based observational study is likely to report less beneficial effect of experimental treatment compared with RCTs (or meta-analysis of RCTs). Copyright © 2014 Elsevier Inc. All rights reserved.

  14. METHODS ADVANCEMENT FOR MILK ANALYSIS: THE MAMA STUDY

    EPA Science Inventory

    The Methods Advancement for Milk Analysis (MAMA) study was designed by US EPA and CDC investigators to provide data to support the technological and study design needs of the proposed National Children=s Study (NCS). The NCS is a multi-Agency-sponsored study, authorized under the...

  15. Combining individual participant and aggregated data in a meta-analysis with correlational studies.

    PubMed

    Pigott, Terri; Williams, Ryan; Polanin, Joshua

    2012-12-01

    This paper presents methods for combining individual participant data (IPD) with aggregated study level data (AD) in a meta-analysis of correlational studies. Although medical researchers have employed IPD in a wide range of studies, only a single example exists in the social sciences. New policies at the National Science Foundation requiring grantees to submit data archiving plans may increase social scientists' access to individual level data that could be combined with traditional meta-analysis. The methods presented here extend prior work on IPD to meta-analyses using correlational studies. The examples presented illustrate the synthesis of publicly available national datasets in education with aggregated study data from a meta-analysis examining the correlation of socioeconomic status measures and academic achievement. The major benefit of the inclusion of the individual level is that both within-study and between-study interactions among moderators of effect size can be estimated. Given the potential growth in data archives in the social sciences, we should see a corresponding increase in the ability to synthesize IPD and AD in a single meta-analysis, leading to a more complete understanding of how within-study and between-study moderators relate to effect size. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.

  16. A Course in Medical Research Study Design and Analysis.

    ERIC Educational Resources Information Center

    Linskey, Mark E.; And Others

    1987-01-01

    A course to familiarize medical students with the principles of good medical research study design and analysis focuses on three types of studies: clinical trials, laboratory science, and epidemiology and biostatistics. (MSE)

  17. Association between telomere length and the risk of colorectal cancer: a meta-analysis of observational studies.

    PubMed

    Naing, Cho; Aung, Kyan; Lai, Pei Kuan; Mak, Joon Wah

    2017-01-05

    Human chromosomes are capped and stabilized by telomeres. Telomere length regulates a 'cellular mitotic clock' that defines the number of cell divisions and hence, cellular life span. This study aimed to synthesize the evidence on the association between peripheral blood leucocytes (PBL) telomere length and the risk of colorectal cancer (CRC). We searched relevant studies in electronic databases. When two or more observational studies reported the same outcome measures, we performed pooled analysis. All the analyses were performed on PBL using PCR. The odds ratio (OR) and its 95% confidence interval (CI) were used to assess the strength of association. Seven studies (with 8 datasets) were included in this meta-analysis; 3 prospective studies, 3 retrospective studies and 1 study with a separate prospective and retrospective designs. The pooled analysis of 4 prospective studies (summary OR 1.01, 95% CI: 0.77-1.34, I 2 :30%) and 4 retrospective studies (summary OR 1.65, 95% CI: 0.96-2.83, I 2 :96%) showed no relationship between PBL telomere length and the CRC risk. A subgroup analysis of 2 prospective studies exclusively on females also showed no association between PBL telomere length and the CRC risk (summary OR, 1.17, 95% CI:0.72-1.91, I 2 :57%). The current analysis is insufficient to provide evidence on the relationship between PBL telomere length and the risk of CRC. Findings suggest that there may be a complex relationship between PBL telomere length and the CRC risk or discrepancy between genetics, age of patients and clinical studies. Future well powered, large prospective studies on the relationship between telomere length and the risk of CRC, and the investigations of the biologic mechanisms are recommended.

  18. Local structure studies of materials using pair distribution function analysis

    NASA Astrophysics Data System (ADS)

    Peterson, Joseph W.

    A collection of pair distribution function studies on various materials is presented in this dissertation. In each case, local structure information of interest pushes the current limits of what these studies can accomplish. The goal is to provide insight into the individual material behaviors as well as to investigate ways to expand the current limits of PDF analysis. Where possible, I provide a framework for how PDF analysis might be applied to a wider set of material phenomena. Throughout the dissertation, I discuss 0 the capabilities of the PDF method to provide information pertaining to a material's structure and properties, ii) current limitations in the conventional approach to PDF analysis, iii) possible solutions to overcome certain limitations in PDF analysis, and iv) suggestions for future work to expand and improve the capabilities PDF analysis.

  19. Are Brazilian Behavior Analysts Publishing Outside the Box? A Survey of General Science Media.

    PubMed

    Dal Ben, Rodrigo; Calixto, Fernanda Castanho; Ferreira, André Luiz

    2017-09-01

    Recent studies have stressed the importance of disseminating behavior analysis to a more diverse audience and have provided ways to do so effectively. General science publications offer an attractive venue for communicating with a scientifically educated public. The present study examines behavior analysis research published in Science Today and Research Fapesp , monthly general science publications published by the Brazilian Society for the Advancement of Science and São Paulo Research Foundation, respectively. Behavior analytic terms were searched in issues published from 2003 to 2014, along with psychoanalytic terms as a comparative measure. Only 13 behavior analysis articles were found, while psychoanalytic articles totaled 150. Six of the behavior analysis articles misconstrue fundamental concepts of behavior analysis. The study recommends that behavior analysis researchers extend the dissemination of their findings outside the box.

  20. Manual Therapy in the Treatment of Idiopathic Scoliosis. Analysis of Current Knowledge.

    PubMed

    Czaprowski, Dariusz

    2016-10-28

    Apart from the recommended specific physiotherapy, the treatment of idiopathic scoliosis (IS) also incorporates non-specific manual therapy (NMT). The aim of this paper is to assess the efficacy of NMT (manual therapy, chiropractic, osteopathy) used in the treatment of children and adolescents with IS. The study analysed systematic reviews (Analysis 1) and other recent scientific publications (Analysis 2). Analysis 1 encompassed papers on the use of NMT in patients with IS. Works concerning specific physiotherapy (SP) or bracing (B) and other types of scoliosis were excluded from the analysis. Inclusion criteria for Analysis 2 were: treatment with NMT; subjects aged 10-18 years with IS. The following types of papers were excluded: works analysing NMT combined with SP or B, reports concerning adult pa tients, analyses of single cases and publications included in Analysis 1. Analysis 1: six systematic reviews contained 6 papers on the efficacy of NMT in the treatment of IS. The results of these studies are contradictory, ranging from Cobb angle reduction to no treatment effects whatsoever. The papers analysed are characterised by poor methodological quality: small group sizes, incomplete descriptions of the study groups, no follow-up and no control groups. Analysis 2: in total, 217 papers were found. None of them met the criteria set for the analysis. 1. Few papers verifying the efficacy of manual therapy, chiropractic and osteopathy in the treatment of idiopathic scoliosis have been published to date. 2. The majority are experimental studies with poor methodology or observational case studies. 3. At present, the efficacy of non-specific manual therapy in the treatment of patients with idiopathic scoliosis cannot be reliably evaluated. 4. It is necessary to conduct further research based on appropriate methods (prospective, rando mi s ed, controlled studies) in order to reliably assess the usefulness of non-specific manual therapy in the treatment of idiopathic scoliosis.

  1. Relationship between Hypothyroidism and Non-Alcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis.

    PubMed

    He, Weiwei; An, Xiaofei; Li, Ling; Shao, Xiaoqing; Li, Qian; Yao, Qiuming; Zhang, Jin-An

    2017-01-01

    Previous studies propose that hypothyroidism might play a crucial role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD), but findings from published studies on the relationship between hypothyroidism and NAFLD are still controversial. Our study aimed to make a comprehensive evaluation of the relationship between hypothyroidism and NAFLD through a meta-analysis. PubMed, China Dissertation Database, and EMBASE databases were searched to find observational studies assessing the relationship between hypothyroidism and NAFLD. The pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated to evaluate the strength of the relationship between hypothyroidism and NAFLD through meta-analysis. Thirteen articles were ultimately included in our meta-analysis. Meta-analysis of the 13 studies found a high correlation between hypothyroidism and NAFLD (OR = 1.52, 95% CI 1.24-1.87, P  < 0.001). Meta-analysis of 9 studies providing adjusted ORs found that hypothyroidism was independently correlated with NAFLD (OR = 1.72, 95% CI 1.32-2.23, P  < 0.001). Subgroup analysis found that both overt hypothyroidism and subclinical hypothyroidism were significantly correlated with NAFLD, and the pooled ORs were 1.70 (95% CI 1.23-2.36, P  = 0.002) and 1.40 (95% CI 1.10-1.77, P  = 0.006), respectively. Besides, meta-analysis of studies providing adjusted ORs also found that both overt hypothyroidism and subclinical hypothyroidism were independently correlated with NAFLD, and the pooled ORs were 1.81 (95% CI 1.30-2.52, P  < 0.001) and 1.63 (95% CI 1.19-2.24, P  = 0.002), respectively. The meta-analysis provides strong epidemiological evidence for the relationship between hypothyroidism and NAFLD. Both individuals with subclinical and overt hypothyroidism are at higher risk for NAFLD than euthyroid subjects.

  2. High performance computing enabling exhaustive analysis of higher order single nucleotide polymorphism interaction in Genome Wide Association Studies.

    PubMed

    Goudey, Benjamin; Abedini, Mani; Hopper, John L; Inouye, Michael; Makalic, Enes; Schmidt, Daniel F; Wagner, John; Zhou, Zeyu; Zobel, Justin; Reumann, Matthias

    2015-01-01

    Genome-wide association studies (GWAS) are a common approach for systematic discovery of single nucleotide polymorphisms (SNPs) which are associated with a given disease. Univariate analysis approaches commonly employed may miss important SNP associations that only appear through multivariate analysis in complex diseases. However, multivariate SNP analysis is currently limited by its inherent computational complexity. In this work, we present a computational framework that harnesses supercomputers. Based on our results, we estimate a three-way interaction analysis on 1.1 million SNP GWAS data requiring over 5.8 years on the full "Avoca" IBM Blue Gene/Q installation at the Victorian Life Sciences Computation Initiative. This is hundreds of times faster than estimates for other CPU based methods and four times faster than runtimes estimated for GPU methods, indicating how the improvement in the level of hardware applied to interaction analysis may alter the types of analysis that can be performed. Furthermore, the same analysis would take under 3 months on the currently largest IBM Blue Gene/Q supercomputer "Sequoia" at the Lawrence Livermore National Laboratory assuming linear scaling is maintained as our results suggest. Given that the implementation used in this study can be further optimised, this runtime means it is becoming feasible to carry out exhaustive analysis of higher order interaction studies on large modern GWAS.

  3. Skill components of task analysis

    PubMed Central

    Rogers, Wendy A.; Fisk, Arthur D.

    2017-01-01

    Some task analysis methods break down a task into a hierarchy of subgoals. Although an important tool of many fields of study, learning to create such a hierarchy (redescription) is not trivial. To further the understanding of what makes task analysis a skill, the present research examined novices’ problems with learning Hierarchical Task Analysis and captured practitioners’ performance. All participants received a task description and analyzed three cooking and three communication tasks by drawing on their knowledge of those tasks. Thirty six younger adults (18–28 years) in Study 1 analyzed one task before training and five afterwards. Training consisted of a general handout that all participants received and an additional handout that differed between three conditions: a list of steps, a flow-diagram, and concept map. In Study 2, eight experienced task analysts received the same task descriptions as in Study 1 and demonstrated their understanding of task analysis while thinking aloud. Novices’ initial task analysis scored low on all coding criteria. Performance improved on some criteria but was well below 100 % on others. Practitioners’ task analyses were 2–3 levels deep but also scored low on some criteria. A task analyst’s purpose of analysis may be the reason for higher specificity of analysis. This research furthers the understanding of Hierarchical Task Analysis and provides insights into the varying nature of task analyses as a function of experience. The derived skill components can inform training objectives. PMID:29075044

  4. Meta-Analysis: Treatment of Attention-Deficit/Hyperactivity Disorder in Children with Comorbod Tic Disorders

    ERIC Educational Resources Information Center

    Bloch, Michael H.; Panza, Kaitlyn E.; Landeros-Weisenberger, Angeli; Leckman, James F.

    2009-01-01

    Methylphenidate appears to provide the greatest and most immediate improvement of the symptoms of attention deficit hyperactivity disorder and does not appear to worsen tic symptoms based on a meta-analysis study. The meta-analysis included nine studies with 477 subjects.

  5. Sequence analysis to assess labour market participation following vocational rehabilitation: an observational study among patients sick-listed with low back pain from a randomised clinical trial in Denmark

    PubMed Central

    Lindholdt, Louise; Labriola, Merete; Nielsen, Claus Vinther; Horsbøl, Trine Allerslev; Lund, Thomas

    2017-01-01

    Introduction The return-to-work (RTW) process after long-term sickness absence is often complex and long and implies multiple shifts between different labour market states for the absentee. Standard methods for examining RTW research typically rely on the analysis of one outcome measure at a time, which will not capture the many possible states and transitions the absentee can go through. The purpose of this study was to explore the potential added value of sequence analysis in supplement to standard regression analysis of a multidisciplinary RTW intervention among patients with low back pain (LBP). Methods The study population consisted of 160 patients randomly allocated to either a hospital-based brief or a multidisciplinary intervention. Data on labour market participation following intervention were obtained from a national register and analysed in two ways: as a binary outcome expressed as active or passive relief at a 1-year follow-up and as four different categories for labour market participation. Logistic regression and sequence analysis were performed. Results The logistic regression analysis showed no difference in labour market participation for patients in the two groups after 1 year. Applying sequence analysis showed differences in subsequent labour market participation after 2 years after baseline in favour of the brief intervention group versus the multidisciplinary intervention group. Conclusion The study indicated that sequence analysis could provide added analytical value as a supplement to traditional regression analysis in prospective studies of RTW among patients with LBP. PMID:28729315

  6. The importance of replication in wildlife research

    USGS Publications Warehouse

    Johnson, D.H.

    2002-01-01

    Wildlife ecology and management studies have been widely criticized for deficiencies in design or analysis. Manipulative experiments--with controls, randomization, and replication in space and time--provide powerful ways of learning about natural systems and establishing causal relationships, but such studies are rare in our field. Observational studies and sample surveys are more common; they also require appropriate design and analysis. More important than the design and analysis of individual studies is metareplication: replication of entire studies. Similar conclusions obtained from studies of the same phenomenon conducted under widely differing conditions will give us greater confidence in the generality of those findings than would any single study, however well designed and executed.

  7. An Analysis of the Quality Assurance Policies in a Ghanian University

    ERIC Educational Resources Information Center

    Seniwoliba, Joseph Attiah; Yakubu, Richard Nalarb

    2015-01-01

    The study examined the implementation challenges of quality assurance in public universities in Ghana with a focus on University for Development Studies (UDS). The study adopted a qualitative case study design. The data for the study was collected through in-depth interviews, document analysis and participants observation. The study revealed that…

  8. Unit Hydrograph Peaking Analysis for Goose Creek Watershed in Virginia: A Case Study

    DTIC Science & Technology

    2017-05-01

    ER D C/ CH L TR -1 7- 6 Unit Hydrograph Peaking Analysis for Goose Creek Watershed in Virginia: A Case Study Co as ta l a nd H yd ra...default. ERDC/CHL TR-17-6 May 2017 Unit Hydrograph Peaking Analysis for Goose Creek Watershed in Virginia: A Case Study Nawa Raj Pradhan and...confidence interval precipitation depths to the watershed in addition to the 50% value. This study concluded that a design event with a return period greater

  9. THE COMMAND OF THE TREND: SOCIAL MEDIA AS A WEAPON IN THE INFORMATION AGE

    DTIC Science & Technology

    2017-06-01

    and a bot network) based on the analysis within this case study . Table 3. ISIS Case Study Analysis Propaganda Narratives 1. ISIS is strong...get started with an interview and included me in a cyber think-tank for the study of ISIS activity on social media. Additionally, I am still... study demonstrates how social media is a tool for modern warfare in the information age. The report builds on analysis of three distinct topics

  10. Exploring the Effect of Video Used to Enhance the Retrospective Verbal Protocol Analysis: A Multiple Case Study

    ERIC Educational Resources Information Center

    Monroe, Steven D.

    2012-01-01

    The purpose of this study was to explore how the use of video in the cognitive task analysis (CTA) retrospective verbal protocol analysis (RVPA) during a job analysis affects: (a) the quality of performing the CTA, (b) the time to complete the CTA, and (c) the cost to execute the CTA. Research has shown when using the simultaneous VPA during a CTA…

  11. Attitudinal Changes of the Student Teacher--A Further Analysis. An Example of an Orthogonal Comparisons Analysis Model Applied to Educational Research.

    ERIC Educational Resources Information Center

    Courtney, E. Wayne

    This report was designed to present an example of a research study involving the use of coefficients of orthogonal comparisons in analysis of variance tests of significance. A sample research report and analysis was included so as to lead the reader through the design steps. The sample study was designed to determine the extent of attitudinal…

  12. Effects of a Gluten-Free Diet on Rate of Learning in Autistic Children in an Applied Behavioral Analysis Program: Summary Analysis.

    ERIC Educational Resources Information Center

    Pontino, Jamie Lyn; Schaal, Kelly; Chambliss, Catherine

    This summary analysis discusses a series of studies that used both between-subjects and within-subjects analyses to examine the effects of a gluten-free diet on the academic achievement of children with autism. In the first study, the between-subjects analysis included data from eight children with autism (ages 5-7), with four on a gluten-free…

  13. Red and processed meat consumption and the risk of lung cancer: a dose-response meta-analysis of 33 published studies

    PubMed Central

    Xue, Xiu-Juan; Gao, Qing; Qiao, Jian-Hong; Zhang, Jie; Xu, Cui-Ping; Liu, Ju

    2014-01-01

    This meta-analysis was to summarize the published studies about the association between red/processed meat consumption and the risk of lung cancer. 5 databases were systematically reviewed, and random-effect model was used to pool the study results and to assess dose-response relationships. Results shown that six cohort studies and twenty eight case-control studies were included in this meat-analysis. The pooled Risk Radios (RR) for total red meat and processed meat were 1.44 (95% CI, 1.29-1.61) and 1.23 (95% CI, 1.10-1.37), respectively. Dose-response analysis revealed that for every increment of 120 grams red meat per day the risk of lung cancer increases 35% and for every increment of 50 grams red meat per day the risk of lung cancer increases 20%. The present dose-response meta-analysis suggested that both red and processed meat consumption showed a positive effect on lung cancer risk. PMID:25035778

  14. Numerical modelling techniques of soft soil improvement via stone columns: A brief review

    NASA Astrophysics Data System (ADS)

    Zukri, Azhani; Nazir, Ramli

    2018-04-01

    There are a number of numerical studies on stone column systems in the literature. Most of the studies found were involved with two-dimensional analysis of the stone column behaviour, while only a few studies used three-dimensional analysis. The most popular software utilised in those studies was Plaxis 2D and 3D. Other types of software that used for numerical analysis are DIANA, EXAMINE, ZSoil, ABAQUS, ANSYS, NISA, GEOSTUDIO, CRISP, TOCHNOG, CESAR, GEOFEM (2D & 3D), FLAC, and FLAC 3. This paper will review the methodological approaches to model stone column numerically, both in two-dimensional and three-dimensional analyses. The numerical techniques and suitable constitutive model used in the studies will also be discussed. In addition, the validation methods conducted were to verify the numerical analysis conducted will be presented. This review paper also serves as a guide for junior engineers through the applicable procedures and considerations when constructing and running a two or three-dimensional numerical analysis while also citing numerous relevant references.

  15. Discourse analysis and the impact of the philosophy of Enlightenment in nursing research.

    PubMed

    Beedholm, Kirsten; Lomborg, Kirsten; Frederiksen, Kirsten

    2014-06-01

    Discourse analysis has been introduced into nursing research as an approach which has the potential to offer new perspectives and to pose new questions to taken-for-granted assumptions. However, critique has arisen that when applied to nursing studies, the epistemological foundation of the discourse analysis is often overlooked. It is furthermore claimed that the methodological inspiration does not lead to any new insights and that these studies can hardly be differentiated from more traditional studies. This study supports this critique, arguing that the challenges of implementing discourse analysis in nursing research reflect a dominant pattern of thought in the discourse of the nursing profession that have held sway throughout the last century. We argue that this pattern of thought stems from the Western philosophy of consciousness and the conception of the sovereign subject. By applying a discourse analytical perspective to the discourse of the nursing profession itself, this study elucidates the challenges of applying discourse analysis in nursing research. © 2013 John Wiley & Sons Ltd.

  16. Trip generation and data analysis study.

    DOT National Transportation Integrated Search

    2015-09-01

    Through the Trip Generation and Data Analysis Study, the District of Columbia Department of : Transportation (DDOT) is undertaking research to better understand multimodal urban trip generation : at mixed-use sites in the District. The study is helpi...

  17. Association of the 5HTR2A gene with suicidal behavior: CASE-control study and updated meta-analysis

    PubMed Central

    2013-01-01

    Background The polymorphism rs6313 (T102C) has been associated with suicidal behavior in case–control and meta-analysis studies, but results and conclusions remain controversial. The aim of the present study was to examine the association between T102C with suicidal behavior in a case–control study and, to assess the combined evidence – this case–control study and available data from other related studies – we carried out a meta-analysis. Methods We conducted a case–control study that included 161 patients with suicide attempts and 244 controls; we then performed a meta-analysis. The following models were evaluated in the meta-analysis: A) C allele vs T allele; B) T allele vs C allele; C) Caucasian population, D) Asian population, and E) suicide attempters with schizophrenia. Results We found an association between attempted suicide and control participants for genotype (χ2=6.28, p=0.04, df=2) and allele (χ2=6.17, p=0.01, df=1, OR 1.48 95% IC: 1.08-2.03) frequencies in the case–control study. The meta-analysis, comprising 23 association studies (including the present one), showed that the rs6313 polymorphism is not associated with suicidal behavior for the following comparisons:T allele vs C allele (OR: 1.03; 95% CI 0.93-1.13; p(Z)=0.44); C allele vs T allele: (OR:0.99; 95% CI: 0.90-1.08; p(Z)=0.22); Caucasians (OR:1.09; 95% CI: 0.96-1.23), and Asians (OR:0.96; 95% CI: 0.84-1.09). Conclusion Our results showed association between the rs6313 (T102C) polymorphism and suicidal behavior in the case–control study. However, the meta-analysis showed no evidence of association. Therefore, more studies are necessary to determine conclusively an association between T102C and suicidal behavior. PMID:23311440

  18. Depression and risk of fracture and bone loss: an updated meta-analysis of prospective studies.

    PubMed

    Wu, Q; Liu, B; Tonmoy, S

    2018-03-12

    This meta-analysis pooled results from 23 qualifying individual cohort studies and found that depression was significantly associated with an increased risk of fractures and bone loss. The association between depression and risk of fracture remains controversial. We conducted a comprehensive meta-analysis to examine the effect of depression on the risk of osteoporotic fractures and bone loss. We searched databases and reviewed citations in relevant articles for eligible cohort studies. Two investigators independently conducted study selection, appraisal, and data abstraction through the use of a standardized protocol. Random effect models were used for meta-analysis. Cochrane Q and I 2 statistics were used to assess heterogeneity. Funnel plots and rank correlation tests were used to evaluate publication bias. Twenty-three studies were included for meta-analysis. In studies that reported hazard ratio (HR) as the outcome (nine studies [n = 309,862]), depression was associated with 26% increase in fracture risk (HR = 1.26, 95% CI, 1.10-1.43, p < 0.001). Studies that reported risk ratio (RR) as the outcome (seven studies [n = 64,975]) suggested that depression was associated with 39% increase in fracture risk (RR = 1.39, 95% CI, 1.19-1.62, p < 0.001). Among studies that reported hip bone mineral density (BMD) as an outcome (eight studies [n = 15,442]), depression was associated with a reduced mean annual bone loss rate of 0.35% (0.18-0.53%, p < 0.001). The increased risk of fracture and bone loss associated with depression was consistent in all meta-analysis having modified inclusion criteria and in different subgroup analyses as well. Significant heterogeneity was observed in the meta-analysis; however, no significant publication bias was detected. Depression is associated with a significant increased risk in fracture and bone loss. Effective prevention may decrease such risk.

  19. Statin use and the risk of Clostridium difficile infection: a systematic review with meta-analysis.

    PubMed

    Tariq, Raseen; Mukhija, Dhruvika; Gupta, Arjun; Singh, Siddharth; Pardi, Darrell S; Khanna, Sahil

    2018-01-01

    Statins have pleiotropic effects beyond cholesterol lowering by immune modulation. The association of statins with primary Clostridium difficile infection (CDI) is unclear as studies have reported conflicting findings. We performed a systematic review and meta-analysis to evaluate the association between statin use and CDI. We searched MEDLINE, Embase, and Web of Science from January 1978 to December 2016 for studies assessing the association between statin use and CDI. The Newcastle-Ottawa Scale was used to assess the methodologic quality of included studies. Weighted summary estimates were calculated using generalized inverse variance with random-effects model. Eight studies (6 case-control and 2 cohort) were included in the meta-analysis, which comprised 156,722 patients exposed to statins and 356,185 controls, with 34,849 total cases of CDI available in 7 studies. The rate of CDI in patients with statin use was 4.3%, compared with 7.8% in patients without statin use. An overall meta-analysis of 8 studies using the random-effects model demonstrated that statins may be associated with a decreased risk of CDI (maximally adjusted odds ratio [OR], 0.80; 95% CI, 0.66-0.97; P =0.02). There was significant heterogeneity among the studies, with an I 2 of 79%. No publication bias was seen. Meta-analysis of studies that adjusted for confounders revealed no protective effect of statins (adjusted OR, 0.84; 95% CI, 0.70-1.01; P =0.06, I 2 =75%). However, a meta-analysis of only full-text studies using the random-effects model demonstrated a decreased risk of CDI with the use of statins (OR 0.77; 95% CI, 0.61-0.99; P =0.04, I 2 =85%). Meta-analyses of existing studies suggest that patients prescribed a statin may be at decreased risk for CDI. The results must be interpreted with caution given the significant heterogeneity and lack of benefit on analysis of studies that adjusted for confounders.

  20. Multivariate Meta-Analysis of Heterogeneous Studies Using Only Summary Statistics: Efficiency and Robustness

    PubMed Central

    Liu, Dungang; Liu, Regina; Xie, Minge

    2014-01-01

    Meta-analysis has been widely used to synthesize evidence from multiple studies for common hypotheses or parameters of interest. However, it has not yet been fully developed for incorporating heterogeneous studies, which arise often in applications due to different study designs, populations or outcomes. For heterogeneous studies, the parameter of interest may not be estimable for certain studies, and in such a case, these studies are typically excluded from conventional meta-analysis. The exclusion of part of the studies can lead to a non-negligible loss of information. This paper introduces a metaanalysis for heterogeneous studies by combining the confidence density functions derived from the summary statistics of individual studies, hence referred to as the CD approach. It includes all the studies in the analysis and makes use of all information, direct as well as indirect. Under a general likelihood inference framework, this new approach is shown to have several desirable properties, including: i) it is asymptotically as efficient as the maximum likelihood approach using individual participant data (IPD) from all studies; ii) unlike the IPD analysis, it suffices to use summary statistics to carry out the CD approach. Individual-level data are not required; and iii) it is robust against misspecification of the working covariance structure of the parameter estimates. Besides its own theoretical significance, the last property also substantially broadens the applicability of the CD approach. All the properties of the CD approach are further confirmed by data simulated from a randomized clinical trials setting as well as by real data on aircraft landing performance. Overall, one obtains an unifying approach for combining summary statistics, subsuming many of the existing meta-analysis methods as special cases. PMID:26190875

  1. Solar Photovoltaic Manufacturing Cost Analysis | Energy Analysis | NREL

    Science.gov Websites

    Solar Photovoltaic Manufacturing Cost Analysis Solar Photovoltaic Manufacturing Cost Analysis NREL's photovoltaic (PV) manufacturing cost analysis-part of our broader effort supporting manufacturing manufacturing sector, and is that growth sustainable? NREL's manufacturing cost analysis studies show that: U.S

  2. A Multidimensional Analysis Tool for Visualizing Online Interactions

    ERIC Educational Resources Information Center

    Kim, Minjeong; Lee, Eunchul

    2012-01-01

    This study proposes and verifies the performance of an analysis tool for visualizing online interactions. A review of the most widely used methods for analyzing online interactions, including quantitative analysis, content analysis, and social network analysis methods, indicates these analysis methods have some limitations resulting from their…

  3. Study protocol for examining job strain as a risk factor for severe unipolar depression in an individual participant meta-analysis of 14 European cohorts.

    PubMed

    Madsen, Ida E H; Hannerz, Harald; Nyberg, Solja T; Magnusson Hanson, Linda L; Ahola, Kirsi; Alfredsson, Lars; Batty, G David; Bjorner, Jakob B; Borritz, Marianne; Burr, Hermann; Dragano, Nico; Ferrie, Jane E; Hamer, Mark; Jokela, Markus; Knutsson, Anders; Koskenvuo, Markku; Koskinen, Aki; Leineweber, Constanze; Nielsen, Martin L; Nordin, Maria; Oksanen, Tuula; Pejtersen, Jan H; Pentti, Jaana; Salo, Paula; Singh-Manoux, Archana; Suominen, Sakari; Theorell, Töres; Toppinen-Tanner, Salla; Vahtera, Jussi; Väänänen, Ari; Westerholm, Peter J M; Westerlund, Hugo; Fransson, Eleonor; Heikkilä, Katriina; Virtanen, Marianna; Rugulies, Reiner; Kivimäki, Mika

    2013-01-01

    Previous studies have shown that gainfully employed individuals with high work demands and low control at work (denoted "job strain") are at increased risk of common mental disorders, including depression. Most existing studies have, however, measured depression using self-rated symptom scales that do not necessarily correspond to clinically diagnosed depression. In addition, a meta-analysis from 2008 indicated publication bias in the field.   This study protocol describes the planned design and analyses of an individual participant data meta-analysis, to examine whether job strain is associated with an increased risk of clinically diagnosed unipolar depression based on hospital treatment registers.  The study will be based on data from approximately 120,000 individuals who participated in 14 studies on work environment and health in 4 European countries. The self-reported working conditions data will be merged with national registers on psychiatric hospital treatment, primarily hospital admissions. Study-specific risk estimates for the association between job strain and depression will be calculated using Cox regressions. The study-specific risk estimates will be pooled using random effects meta-analysis.   The planned analyses will help clarify whether job strain is associated with an increased risk of clinically diagnosed unipolar depression. As the analysis is based on pre-planned study protocols and an individual participant data meta-analysis, the pooled risk estimates will not be influenced by selective reporting and publication bias. However, the results of the planned study may only pertain to severe cases of unipolar depression, because of the outcome measure applied.

  4. A Comparison of Various MRA Methods Applied to Longitudinal Evaluation Studies in Vocational Education.

    ERIC Educational Resources Information Center

    Kapes, Jerome T.; And Others

    Three models of multiple regression analysis (MRA): single equation, commonality analysis, and path analysis, were applied to longitudinal data from the Pennsylvania Vocational Development Study. Variables influencing weekly income of vocational education students one year after high school graduation were examined: grade point averages (grades…

  5. Development of a Methodology for Assessing Aircrew Workloads.

    DTIC Science & Technology

    1981-11-01

    Workload Feasibility Study. .. ...... 52 Subjects. .. .............. ........ 53 Equipment .. ............... ....... 53 Date Analysis ... analysis ; simulation; standard time systems; switching synthetic time systems; task activities; task interference; time study; tracking; workload; work sampl...standard data systems, information content analysis , work sampling and job evaluation. Con- ventional methods were found to be deficient in accounting

  6. Effects of Computer-Based Training on Procedural Modifications to Standard Functional Analyses

    ERIC Educational Resources Information Center

    Schnell, Lauren K.; Sidener, Tina M.; DeBar, Ruth M.; Vladescu, Jason C.; Kahng, SungWoo

    2018-01-01

    Few studies have evaluated methods for training decision-making when functional analysis data are undifferentiated. The current study evaluated computer-based training to teach 20 graduate students to arrange functional analysis conditions, analyze functional analysis data, and implement procedural modifications. Participants were exposed to…

  7. Shared Decision-Making and the Limits of Democratization: A Case Study of Site-Based Reform.

    ERIC Educational Resources Information Center

    Radnofsky, Mary L.; Spielmann, Guy

    This paper presents findings of an ethnographic study of a school district's Staff Development, Supervision, and Evaluation Program (SDSEP). Data were gathered through interviews, observations, participant observation, analysis of kinesics and proxemics, semiotic analysis of discourse, unobtrusive measures, and analysis of official documents. The…

  8. Image Analysis, Microscopic, and Spectrochemical Study of the PVC Dry Blending Process,

    DTIC Science & Technology

    The dry blending process used in the production of electrical grade pvc formulations has been studies using a combination of image analysis , microscopic...by image analysis techniques. Optical and scanning electron microscopy were used to assess morphological differences. Spectrochemical techniques were used to indicate chemical changes.

  9. REAL-TIME ENERGY INFORMATION AND CONSUMER BEHAVIOR: A META-ANALYSIS AND FORECAST

    EPA Science Inventory

    The meta-analysis of literature and program results will shed light on potential causes of study-to-study variation in information feedback programs and trials. Outputs from the meta-analysis, such as price elasticity, will be used in NEMS to estimate the impact of a nation...

  10. The Information Professional's Profile: An Analysis of Brazilian Job Vacancies on the Internet

    ERIC Educational Resources Information Center

    da Cunha, Miriam Vieira

    2009-01-01

    Introduction: Report of a study to discover and describe job vacancies for information professionals available online at specific sites and discussion lists between January 2005 and February 2008. Method: The study uses Bardin's content analysis technique and the following analysis criteria: information source, institutional type, professional…

  11. An Ecological Analysis of Mathematics Teachers' Noticing

    ERIC Educational Resources Information Center

    Jazby, Dan

    2016-01-01

    Most studies which investigate mathematics teacher noticing cast perception into a passive role. This study develops an ecological analysis of mathematics teachers' noticing in order to investigate how teachers actively look for information in classroom environments. This method of analysis is applied to data collected as an experienced primary…

  12. Linking Brief Functional Analysis to Intervention Design in General Education Settings

    ERIC Educational Resources Information Center

    Ishuin, Tifanie

    2009-01-01

    This study focused on the utility and applicability of brief functional analysis in general education settings. The purpose of the study was to first identify the environmental variables maintaining noncompliance through a brief functional analysis, and then to design and implement a functionally equivalent intervention. The participant exhibited…

  13. Default-Mode Network Functional Connectivity in Aphasia: Therapy-Induced Neuroplasticity

    ERIC Educational Resources Information Center

    Marcotte, Karine; Perlbarg, Vincent; Marrelec, Guillaume; Benali, Habib; Ansaldo, Ana Ines

    2013-01-01

    Previous research on participants with aphasia has mainly been based on standard functional neuroimaging analysis. Recent studies have shown that functional connectivity analysis can detect compensatory activity, not revealed by standard analysis. Little is known, however, about the default-mode network in aphasia. In the current study, we studied…

  14. A User's Guide to the Meta-Analysis of Research Studies. Meta-Stat: Software To Aid in the Meta-Analysis of Research Findings.

    ERIC Educational Resources Information Center

    Rudner, Lawrence M.; Glass Gene V.; Evartt, David L.; Emery, Patrick J.

    This manual and the accompanying software are intended to provide a step-by-step guide to conducting a meta-analytic study along with references for further reading and free high-quality software, "Meta-Stat.""Meta-Stat" is a comprehensive package designed to help in the meta-analysis of research studies in the social and behavioral sciences.…

  15. A Second Look at Dwyer's Studies by Means of Meta-Analysis: The Effects of Pictorial Realism on Text Comprehension and Vocabulary.

    ERIC Educational Resources Information Center

    Reinwein, Joachim; Huberdeau, Lucie

    A meta-analysis examined a series of studies by F.M. Dwyer on the effect of illustrations on text comprehension. Principal component analysis was used to reduce the four posttests used by Dwyer to more fundamental factors of learning, followed by analyses of variance. All nine studies (involving secondary-school and college students) in which…

  16. Proceedings: Economic and Social Analysis Workshop Held at St. Louis, Missouri on 25-29 October 1982,

    DTIC Science & Technology

    1983-10-01

    institutional factors for determining the discount rate. For instance tax impact analysis is particularly troublesome. According to one recent study ...STAND-ALONE TECHNICAL REPORT. THE FOLLOWING COMPONENT PART NUMBERS COMPRISE THE COMPILATION REPORT: AW: TIILE: AD-P002 631 National Waterways Study ...for Military Programs: The Fort -;1uchanan, Puerto Rico, Realignment Study . AD-P002 646 Economic Analysis of Alternative Military Housing

  17. Reproductive disorders among cosmetologists and hairdressers: a meta-analysis.

    PubMed

    Kim, Dohyung; Kang, Mo-Yeol; Choi, Sungyeul; Park, Jaechan; Lee, Hye-Ji; Kim, Eun-A

    2016-07-01

    Occupational risks for reproductive disorders among hairdressers and cosmetologists have been examined in numerous epidemiological studies, although the results of those studies have been inconsistent. Therefore, we conducted a meta-analysis of published studies to evaluate the risks of reproductive disorders among cosmetologists and hairdressers. We searched the MEDLINE, EMBASE, and Cochrane Library databases, as well as the reference lists of relevant publications, to identify studies for our analysis. After careful consideration, 19 eligible studies were included in the meta-analysis. We also performed systematic evaluations of publication bias, heterogeneity, and publication quality. Study-specific odds ratios (ORs) were weighted using the inverse of their variance to calculate fixed- and random-effect pooled estimates. The meta-analysis revealed a significantly increased risk of infertility (OR 1.15, 95 % CI 1.03-1.28), fetal death (OR 1.14, 95 % CI 1.04-1.24), and preterm delivery (OR 1.04, 95 % CI 1.00-1.07) among hairdressers and cosmetologists. These findings indicate that hairdressers and cosmetologists have a higher risk of reproductive disorders, compared to the general population.

  18. Caffeinated and decaffeinated coffee consumption and melanoma risk: a dose-response meta-analysis of prospective cohort studies.

    PubMed

    Micek, Agnieszka; Godos, Justyna; Lafranconi, Alessandra; Marranzano, Marina; Pajak, Andrzej

    2018-06-01

    To determine the association between total, caffeinated and decaffeinated coffee consumption and melanoma risk a dose-response meta-analysis on prospective cohort studies were performed. Eligible studies were identified searching PubMed and EMBASE databases from the earliest available online indexing year to March 2017. The dose-response relationship was assessed by random-effects meta-analysis and the shape of the exposure-outcome curve was modelled linearly and using restricted cubic splines. A total of seven studies eligible for meta-analysis were identified that comprised 1,418,779 participants and 9211 melanoma cases. A linear dose-response meta-analysis showed a significant association between total coffee consumption and melanoma risk. An increase in coffee consumption of one cup per day was associated with a 3% reduction in melanoma risk (RR 0.97; 95% CI 0.95-0.99). Our findings suggest that coffee intake may be inversely associated with incidence of melanoma. Nevertheless, further studies exploring also the role of confounding factors are needed to explain the heterogeneity among studies.

  19. Dietary fat intake and ovarian cancer risk: a meta-analysis of epidemiological studies

    PubMed Central

    Qiu, Wenlong; Lu, Heng; Qi, Yana; Wang, Xiuwen

    2016-01-01

    Observational studies assessing the association of dietary fat and risk of ovarian cancer yield discrepant results. Pertinent prospective cohort studies were identified by a PubMed search from inception to December 2015. Sixteen independent case-control and nine cohort studies on dietary fat intake were included, with approximately 900,000 subjects in total. Relative risks (RRs) with 95% confidence intervals were pooled using a random effects model. Heterogeneity, sensitivity analysis and publication bias were assessed; subgroup analysis and analysis stratified by EOC histology were conducted. The reported studies showed a significant increase of ovarian cancer risk with high consumption of total-, saturated-, and trans-fats, while serous ovarian cancer was more susceptible to dietary fat consumption than other pathological subtypes. No evidence of positive association between dietary fat intake and ovarian cancer risk was provided by cohort studies. Menopausal status, hormone replacement therapy, body mass index (BMI), and pregnancy times, modified the objective associations. In conclusion, the meta-analysis findings indicate that high consumption of total, saturated and trans-fats increase ovarian cancer risk, and different histological subtypes have different susceptibility to dietary fat. PMID:27119509

  20. Intraoral distalizer effects with conventional and skeletal anchorage: a meta-analysis.

    PubMed

    Grec, Roberto Henrique da Costa; Janson, Guilherme; Branco, Nuria Castello; Moura-Grec, Patrícia Garcia; Patel, Mayara Paim; Castanha Henriques, José Fernando

    2013-05-01

    The aims of this meta-analysis were to quantify and to compare the amounts of distalization and anchorage loss of conventional and skeletal anchorage methods in the correction of Class II malocclusion with intraoral distalizers. The literature was searched through 5 electronic databases, and inclusion criteria were applied. Articles that presented pretreatment and posttreatment cephalometric values were preferred. Quality assessments of the studies were performed. The averages and standard deviations of molar and premolar effects were extracted from the studies to perform a meta-analysis. After applying the inclusion and exclusion criteria, 40 studies were included in the systematic review. After the quality analysis, 2 articles were classified as high quality, 27 as medium quality, and 11 as low quality. For the meta-analysis, 6 studies were included, and they showed average molar distalization amounts of 3.34 mm with conventional anchorage and 5.10 mm with skeletal anchorage. The meta-analysis of premolar movement showed estimates of combined effects of 2.30 mm (mesialization) in studies with conventional anchorage and -4.01 mm (distalization) in studies with skeletal anchorage. There was scientific evidence that both anchorage systems are effective for distalization; however, with skeletal anchorage, there was no anchorage loss when direct anchorage was used. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  1. Archaeology: site studies, activation analysis, preservation, and remote sensing. 1978-November 1979 (citations from the NTIS Data Base). Report for 1978-November 1979

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1981-01-01

    This bibliography contains general studies as well as chemical analysis of archaeological specimens. The chemical analysis is mainly activation analysis of articles such as metals, pottery, coins, paintings, soils, glass and paper from Medieval, Grecian, Egyptian, Mayan, and prehistoric times. The general studies include results of excavation from the United States. Also covered is work on preservation of artifacts and remote sensing for the site location. (This updated bibliography contains 237 citations, none of which are new entries to the previous edition.)

  2. Integrating genome-wide association study and expression quantitative trait loci data identifies multiple genes and gene set associated with neuroticism.

    PubMed

    Fan, Qianrui; Wang, Wenyu; Hao, Jingcan; He, Awen; Wen, Yan; Guo, Xiong; Wu, Cuiyan; Ning, Yujie; Wang, Xi; Wang, Sen; Zhang, Feng

    2017-08-01

    Neuroticism is a fundamental personality trait with significant genetic determinant. To identify novel susceptibility genes for neuroticism, we conducted an integrative analysis of genomic and transcriptomic data of genome wide association study (GWAS) and expression quantitative trait locus (eQTL) study. GWAS summary data was driven from published studies of neuroticism, totally involving 170,906 subjects. eQTL dataset containing 927,753 eQTLs were obtained from an eQTL meta-analysis of 5311 samples. Integrative analysis of GWAS and eQTL data was conducted by summary data-based Mendelian randomization (SMR) analysis software. To identify neuroticism associated gene sets, the SMR analysis results were further subjected to gene set enrichment analysis (GSEA). The gene set annotation dataset (containing 13,311 annotated gene sets) of GSEA Molecular Signatures Database was used. SMR single gene analysis identified 6 significant genes for neuroticism, including MSRA (p value=2.27×10 -10 ), MGC57346 (p value=6.92×10 -7 ), BLK (p value=1.01×10 -6 ), XKR6 (p value=1.11×10 -6 ), C17ORF69 (p value=1.12×10 -6 ) and KIAA1267 (p value=4.00×10 -6 ). Gene set enrichment analysis observed significant association for Chr8p23 gene set (false discovery rate=0.033). Our results provide novel clues for the genetic mechanism studies of neuroticism. Copyright © 2017. Published by Elsevier Inc.

  3. Robustness of meta-analyses in finding gene × environment interactions

    PubMed Central

    Shi, Gang; Nehorai, Arye

    2017-01-01

    Meta-analyses that synthesize statistical evidence across studies have become important analytical tools for genetic studies. Inspired by the success of genome-wide association studies of the genetic main effect, researchers are searching for gene × environment interactions. Confounders are routinely included in the genome-wide gene × environment interaction analysis as covariates; however, this does not control for any confounding effects on the results if covariate × environment interactions are present. We carried out simulation studies to evaluate the robustness to the covariate × environment confounder for meta-regression and joint meta-analysis, which are two commonly used meta-analysis methods for testing the gene × environment interaction or the genetic main effect and interaction jointly. Here we show that meta-regression is robust to the covariate × environment confounder while joint meta-analysis is subject to the confounding effect with inflated type I error rates. Given vast sample sizes employed in genome-wide gene × environment interaction studies, non-significant covariate × environment interactions at the study level could substantially elevate the type I error rate at the consortium level. When covariate × environment confounders are present, type I errors can be controlled in joint meta-analysis by including the covariate × environment terms in the analysis at the study level. Alternatively, meta-regression can be applied, which is robust to potential covariate × environment confounders. PMID:28362796

  4. Prevalence of hyperphagia in Alzheimer's disease: a meta-analysis.

    PubMed

    Shea, Yat-Fung; Lee, Shui-Ching; Chu, Leung-Wing

    2018-02-06

    Unlike other behavioural and psychological symptoms of dementia, hyperphagia is less recognized among patients with Alzheimer's disease (AD). The prevalence of hyperphagia varies among studies, but there has been no systematic review or meta-analysis. An extensive search on the literature on hyperphagia in AD published between 1 January 1980 and 30 October 2017 was conducted. Data on the prevalence were retrieved. Meta-analysis with a random effect model was performed to determine the pooled estimate of prevalence. Meta-regression analysis was performed based on study characteristics, population demographics, or condition information. Results from 20 studies were extracted. Twenty-six reported cases of hyperphagia were identified. The mean age of onset was 70.7 ± 8.9 years, with a male predominance (68.4%). Hyperphagia occurred in all stages of AD. Only eight studies reported the prevalence of hyperphagia. Meta-analysis showed a pooled prevalence of hyperphagia of 18.6%. Publication bias may have been present. Meta-regression showed that ethnicity accounted for the variance among studies (coefficient: -1.247 (95% confidence interval: -1.978 to -0.516), R 2 analogue: 0.77, P < 0.001). Hyperphagia occurs in all stages of AD. In this meta-analysis of eight published studies, the prevalence of hyperphagia was 18.6%. In view of the possible publication bias, a large-scale study on hyperphagia is recommended in the future. © 2018 Japanese Psychogeriatric Society.

  5. The political economy of United States multiutilities: The United States electric power industry and communication services

    NASA Astrophysics Data System (ADS)

    Quail, Christine M.

    This study consists of a political economic analysis of the multiutility industry, the industry located at the confluence of electric utilities, telephone, cable, and Internet markets. The study uses a theoretical framework based in political economy and urban theory. Methodologies used include industrial analysis and instrumental analysis. A discussion of technological convergence establishes the technical means by which multiutilities developed. Refusing technological determinism, however, the study presents a critical analysis of the history, philosophy, and regulation of utilities. Distinctions are made between public and private ownership structures in the electric utility industry. Next, the study embarks on an industrial analysis of the multiutility industry. The industrial analysis includes a discussion of the industry's history, markets, ownership types, and legal struggles. Following the broad industrial overview, two case studies are presented: Hawarden Integrated Technology, Energy and Communications (HITEC), and Con Edison Communications, LLC. HITEC is a public multiutility in the City of Hawarden, Iowa. Con Edison Communications is a private multiutility, based in New York City. The case studies provide a vehicle by which theoretical and philosophical underpinnings, as well as general trends, in the multiutility industry are localized and concretized. Finally, the study draws conclusions about the nature, history, and future of public versus private control of multiutilities' converged communications infrastructures. Questions of democratic control of media infrastructures are raised.

  6. Assessment of Reliable Change Using 95% Credible Intervals for the Differences in Proportions: A Statistical Analysis for Case-Study Methodology.

    PubMed

    Unicomb, Rachael; Colyvas, Kim; Harrison, Elisabeth; Hewat, Sally

    2015-06-01

    Case-study methodology studying change is often used in the field of speech-language pathology, but it can be criticized for not being statistically robust. Yet with the heterogeneous nature of many communication disorders, case studies allow clinicians and researchers to closely observe and report on change. Such information is valuable and can further inform large-scale experimental designs. In this research note, a statistical analysis for case-study data is outlined that employs a modification to the Reliable Change Index (Jacobson & Truax, 1991). The relationship between reliable change and clinical significance is discussed. Example data are used to guide the reader through the use and application of this analysis. A method of analysis is detailed that is suitable for assessing change in measures with binary categorical outcomes. The analysis is illustrated using data from one individual, measured before and after treatment for stuttering. The application of this approach to assess change in categorical, binary data has potential application in speech-language pathology. It enables clinicians and researchers to analyze results from case studies for their statistical and clinical significance. This new method addresses a gap in the research design literature, that is, the lack of analysis methods for noncontinuous data (such as counts, rates, proportions of events) that may be used in case-study designs.

  7. Vitamin D Deficiency Increases the Risk of Gestational Diabetes Mellitus: A Meta-Analysis of Observational Studies

    PubMed Central

    Zhang, Meng-Xi; Pan, Guo-Tao; Guo, Jian-Fen; Li, Bing-Yan; Qin, Li-Qiang; Zhang, Zeng-Li

    2015-01-01

    The results investigating the relationship between vitamin D levels and gestational diabetes mellitus (GDM) are inconsistent. Thus, we focused on evaluating the association of vitamin D deficiency with GDM by conducting a meta-analysis of observed studies. A systematic literature search was conducted via PubMed, MEDLINE, and Cochrane library to identify eligible studies before August 2015. The meta-analysis of 20 studies including 9209 participants showed that women with vitamin D deficiency experienced a significantly increased risk for developing GDM (odds ratio (OR) = 1.53; 95% confidence intervals (CI), 1.33, 1.75) with a little heterogeneity (I2 = 16.20%, p = 0.252). A noteworthy decrease of 4.93 nmol/L (95% CI, −6.73, −3.14) in serum 25(OH)D was demonstrated in the participants with GDM, and moderate heterogeneity was observed (I2 = 61.40%, p = 0.001). Subgroup analysis with study design showed that there were obvious heterogeneities in nested case–control studies (I2 > 52.5%, p < 0.07). Sensitivity analysis showed that exclusion of any single study did not materially alter the overall combined effect. In summary, the evidence from this meta-analysis indicates a consistent association between vitamin D deficiency and an increased risk of GDM. However, well-designed randomized controlled trials are needed to elicit the clear effect of vitamin D supplementation on prevention of GDM. PMID:26437429

  8. Dietary Inflammatory Potential Score and Risk of Breast Cancer: Systematic Review and Meta-analysis.

    PubMed

    Zahedi, Hoda; Djalalinia, Shirin; Sadeghi, Omid; Asayesh, Hamid; Noroozi, Mehdi; Gorabi, Armita Mahdavi; Mohammadi, Rasool; Qorbani, Mostafa

    2018-02-07

    Several studies have been conducted on the relationship between dietary inflammatory potential (DIP) and breast cancer. However, the findings are conflicting. This systematic review and meta-analysis summarizes the findings on the association between DIP and the risk of breast cancer. We used relevant keywords and searched online international electronic databases, including PubMed and NLM Gateway (for Medline), Institute for Scientific Information (ISI), and Scopus for articles published through February 2017. All cross-sectional, case-control, and cohort studies were included in this meta-analysis. Meta-analysis was performed using the random effects meta-analysis method to address heterogeneity among studies. Findings were analyzed statistically. Nine studies were included in the present systematic review and meta-analysis. The total sample size of these studies was 296,102, and the number of participants varied from 1453 to 122,788. The random effects meta-analysis showed a positive and significant association between DIP and the risk of breast cancer (pooled odds ratio, 1.14; 95% confidence interval, 1.01-1.27). The pooled effect size was not statistically significant because of the type of studies, including cohort (pooled relative risk, 1.04; 95% confidence interval, 0.98-1.10) and case-control (pooled odds ratio, 1.63; 95% confidence interval, 0.89-2.37) studies. We found a significant and positive association between higher DIP score and risk of breast cancer. Modifying inflammatory characteristics of diet can substantially reduce the risk of breast cancer. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. Association between the BRCA2 rs144848 polymorphism and cancer susceptibility: a meta-analysis.

    PubMed

    Li, Qiuyan; Guan, Rongwei; Qiao, Yuandong; Liu, Chang; He, Ning; Zhang, Xuelong; Jia, Xueyuan; Sun, Haiming; Yu, Jingcui; Xu, Lidan

    2017-06-13

    The BRCA2 gene plays an important role in cancer carcinogenesis, and polymorphisms in this gene have been associated with cancer risk. The BRCA2 rs144848 polymorphism has been associated with several cancers, but results have been inconsistent. In the present study, a meta-analysis was performed to assess the association between the rs144848 polymorphism and cancer risk. Literature was searched from the databases of PubMed, Embase and Google Scholar before April 2016. The fixed or random effects model was used to calculate pooled odd ratios on the basis of heterogeneity. Meta-regression, sensitivity analysis, subgroup analysis and publication bias assessment were also performed using STATA 11.0 software according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009. A total of 40 relevant studies from 30 publications including 34,911 cases and 48,329 controls were included in the final meta-analysis. Among them, 22 studies focused on breast cancer, seven on ovarian cancer, five on non-Hodgkin lymphoma, and the remaining six studies examined various other cancers. The meta-analysis results showed that there were significant associations between the rs144848 polymorphism and cancer risk in all genetic models. Stratified by cancer type, the rs144848 polymorphism was associated with non-Hodgkin lymphoma. Stratified by study design, the allele model was associated with breast cancer risk in population-based studies. The meta-analysis suggests that the BRCA2 rs144848 polymorphism may play a role in cancer risk. Further well-designed studies are warranted to confirm these results.

  10. Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Current and advanced act control system definition study. Volume 2: Appendices

    NASA Technical Reports Server (NTRS)

    Hanks, G. W.; Shomber, H. A.; Dethman, H. A.; Gratzer, L. B.; Maeshiro, A.; Gangsaas, D.; Blight, J. D.; Buchan, S. M.; Crumb, C. B.; Dorwart, R. J.

    1981-01-01

    The current status of the Active Controls Technology (ACT) for the advanced subsonic transport project is investigated through analysis of the systems technical data. Control systems technologies under examination include computerized reliability analysis, pitch axis fly by wire actuator, flaperon actuation system design trade study, control law synthesis and analysis, flutter mode control and gust load alleviation analysis, and implementation of alternative ACT systems. Extensive analysis of the computer techniques involved in each system is included.

  11. Pivot tables for mortality analysis, or who needs life tables anyway?

    PubMed

    Wesley, David; Cox, Hugh F

    2007-01-01

    Actuarial life-table analysis has long been used by life insurance medical directors for mortality abstraction from clinical studies. Ironically, today's life actuary instead uses pivot tables to analyze mortality. Pivot tables (a feature/function in MS Excel) collapse various dimensions of data that were previously arranged in an "experience study" format. Summary statistics such as actual deaths, actual and expected mortality (usually measured in dollars), and calculated results such as actual to expected ratios, are then displayed in a 2-dimensional grid. The same analytic process, excluding the dollar focus, can be used for clinical mortality studies. For raw survival data, especially large datasets, this combination of experience study data and pivot tables has clear advantages over life-table analysis in both accuracy and flexibility. Using the SEER breast cancer data, we compare the results of life-table analysis and pivot-table analysis.

  12. Multivariate meta-analysis with an increasing number of parameters

    PubMed Central

    Boca, Simina M.; Pfeiffer, Ruth M.; Sampson, Joshua N.

    2017-01-01

    Summary Meta-analysis can average estimates of multiple parameters, such as a treatment’s effect on multiple outcomes, across studies. Univariate meta-analysis (UVMA) considers each parameter individually, while multivariate meta-analysis (MVMA) considers the parameters jointly and accounts for the correlation between their estimates. The performance of MVMA and UVMA has been extensively compared in scenarios with two parameters. Our objective is to compare the performance of MVMA and UVMA as the number of parameters, p, increases. Specifically, we show that (i) for fixed-effect meta-analysis, the benefit from using MVMA can substantially increase as p increases; (ii) for random effects meta-analysis, the benefit from MVMA can increase as p increases, but the potential improvement is modest in the presence of high between-study variability and the actual improvement is further reduced by the need to estimate an increasingly large between study covariance matrix; and (iii) when there is little to no between study variability, the loss of efficiency due to choosing random effects MVMA over fixed-effect MVMA increases as p increases. We demonstrate these three features through theory, simulation, and a meta-analysis of risk factors for Non-Hodgkin Lymphoma. PMID:28195655

  13. The choice of prior distribution for a covariance matrix in multivariate meta-analysis: a simulation study.

    PubMed

    Hurtado Rúa, Sandra M; Mazumdar, Madhu; Strawderman, Robert L

    2015-12-30

    Bayesian meta-analysis is an increasingly important component of clinical research, with multivariate meta-analysis a promising tool for studies with multiple endpoints. Model assumptions, including the choice of priors, are crucial aspects of multivariate Bayesian meta-analysis (MBMA) models. In a given model, two different prior distributions can lead to different inferences about a particular parameter. A simulation study was performed in which the impact of families of prior distributions for the covariance matrix of a multivariate normal random effects MBMA model was analyzed. Inferences about effect sizes were not particularly sensitive to prior choice, but the related covariance estimates were. A few families of prior distributions with small relative biases, tight mean squared errors, and close to nominal coverage for the effect size estimates were identified. Our results demonstrate the need for sensitivity analysis and suggest some guidelines for choosing prior distributions in this class of problems. The MBMA models proposed here are illustrated in a small meta-analysis example from the periodontal field and a medium meta-analysis from the study of stroke. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  14. Disorganization of white matter architecture in major depressive disorder: a meta-analysis of diffusion tensor imaging with tract-based spatial statistics.

    PubMed

    Chen, Guangxiang; Hu, Xinyu; Li, Lei; Huang, Xiaoqi; Lui, Su; Kuang, Weihong; Ai, Hua; Bi, Feng; Gu, Zhongwei; Gong, Qiyong

    2016-02-24

    White matter (WM) abnormalities have long been suspected in major depressive disorder (MDD). Tract-based spatial statistics (TBSS) studies have detected abnormalities in fractional anisotropy (FA) in MDD, but the available evidence has been inconsistent. We performed a quantitative meta-analysis of TBSS studies contrasting MDD patients with healthy control subjects (HCS). A total of 17 studies with 18 datasets that included 641 MDD patients and 581 HCS were identified. Anisotropic effect size-signed differential mapping (AES-SDM) meta-analysis was performed to assess FA alterations in MDD patients compared to HCS. FA reductions were identified in the genu of the corpus callosum (CC) extending to the body of the CC and left anterior limb of the internal capsule (ALIC) in MDD patients relative to HCS. Descriptive analysis of quartiles, sensitivity analysis and subgroup analysis further confirmed these findings. Meta-regression analysis revealed that individuals with more severe MDD were significantly more likely to have FA reductions in the genu of the CC. This study provides a thorough profile of WM abnormalities in MDD and evidence that interhemispheric connections and frontal-striatal-thalamic pathways are the most convergent circuits affected in MDD.

  15. Melanocortin-1 receptor, skin cancer and phenotypic characteristics (M-SKIP) project: study design and methods for pooling results of genetic epidemiological studies

    PubMed Central

    2012-01-01

    Background For complex diseases like cancer, pooled-analysis of individual data represents a powerful tool to investigate the joint contribution of genetic, phenotypic and environmental factors to the development of a disease. Pooled-analysis of epidemiological studies has many advantages over meta-analysis, and preliminary results may be obtained faster and with lower costs than with prospective consortia. Design and methods Based on our experience with the study design of the Melanocortin-1 receptor (MC1R) gene, SKin cancer and Phenotypic characteristics (M-SKIP) project, we describe the most important steps in planning and conducting a pooled-analysis of genetic epidemiological studies. We then present the statistical analysis plan that we are going to apply, giving particular attention to methods of analysis recently proposed to account for between-study heterogeneity and to explore the joint contribution of genetic, phenotypic and environmental factors in the development of a disease. Within the M-SKIP project, data on 10,959 skin cancer cases and 14,785 controls from 31 international investigators were checked for quality and recoded for standardization. We first proposed to fit the aggregated data with random-effects logistic regression models. However, for the M-SKIP project, a two-stage analysis will be preferred to overcome the problem regarding the availability of different study covariates. The joint contribution of MC1R variants and phenotypic characteristics to skin cancer development will be studied via logic regression modeling. Discussion Methodological guidelines to correctly design and conduct pooled-analyses are needed to facilitate application of such methods, thus providing a better summary of the actual findings on specific fields. PMID:22862891

  16. Meta-analysis of haplotype-association studies: comparison of methods and empirical evaluation of the literature

    PubMed Central

    2011-01-01

    Background Meta-analysis is a popular methodology in several fields of medical research, including genetic association studies. However, the methods used for meta-analysis of association studies that report haplotypes have not been studied in detail. In this work, methods for performing meta-analysis of haplotype association studies are summarized, compared and presented in a unified framework along with an empirical evaluation of the literature. Results We present multivariate methods that use summary-based data as well as methods that use binary and count data in a generalized linear mixed model framework (logistic regression, multinomial regression and Poisson regression). The methods presented here avoid the inflation of the type I error rate that could be the result of the traditional approach of comparing a haplotype against the remaining ones, whereas, they can be fitted using standard software. Moreover, formal global tests are presented for assessing the statistical significance of the overall association. Although the methods presented here assume that the haplotypes are directly observed, they can be easily extended to allow for such an uncertainty by weighting the haplotypes by their probability. Conclusions An empirical evaluation of the published literature and a comparison against the meta-analyses that use single nucleotide polymorphisms, suggests that the studies reporting meta-analysis of haplotypes contain approximately half of the included studies and produce significant results twice more often. We show that this excess of statistically significant results, stems from the sub-optimal method of analysis used and, in approximately half of the cases, the statistical significance is refuted if the data are properly re-analyzed. Illustrative examples of code are given in Stata and it is anticipated that the methods developed in this work will be widely applied in the meta-analysis of haplotype association studies. PMID:21247440

  17. Proton-pump inhibitors and risk of fractures: an update meta-analysis.

    PubMed

    Zhou, B; Huang, Y; Li, H; Sun, W; Liu, J

    2016-01-01

    To identify the relationship between proton-pump inhibitors (PPIs) and the risk of fracture, we conducted an update meta-analysis of observational studies. Results showed that PPI use was associated with a modestly increased risk of hip, spine, and any-site fracture. Many studies have investigated the association of proton-pump inhibitors (PPIs) with fracture risk, but the results have been inconsistent. To evaluate this question, we performed a meta-analysis of relevant observational studies. A systematic literature search up to February 2015 was performed in PubMed. We combined relative risks (RRs) for fractures using random-effects models and conducted subgroup and stratified analyses. Eighteen studies involving a total of 244,109 fracture cases were included in this meta-analysis. Pooled analysis showed that PPI use could moderately increase the risk of hip fracture [RR = 1.26, 95 % confidence intervals (CIs) 1.16–1.36]. There was statistically significant heterogeneity among studies (p < 0.001; I 2 = 71.9 %). After limiting to cohort studies, there was also a moderate increase in hip fracture risk without evidence of study heterogeneity. Pooling revealed that short-term use (<1 year) and longer use (>1 year) were similarly associated with increased risk of hip fracture. Furthermore, a moderately increased risk of spine (RR = 1.58, 95 % CI 1.38–1.82) and any-site fracture (RR = 1.33, 95 % CI 1.15–1.54) was also found among PPI users. In this update meta-analysis of observational studies, PPI use modestly increased the risk of hip, spine, and any-site fracture, but no evidence of duration effect in subgroup analysis.

  18. Investigation of the Study Characteristics Affecting Clinical Trial Quality Using the Protocol Deviations Leading to Exclusion of Subjects From the Per Protocol Set Data in Studies for New Drug Application: A Retrospective Analysis.

    PubMed

    Kohara, Norihito; Kaneko, Masayuki; Narukawa, Mamoru

    2018-01-01

    The concept of the risk-based approach has been introduced as an effort to secure the quality of clinical trials. In the risk-based approach, identification and evaluation of risk in advance are considered important. For recently completed clinical trials, we investigated the relationship between study characteristics and protocol deviations leading to the exclusion of subjects from Per Protocol Set (PPS) efficacy analysis. New drugs approved in Japan in the fiscal year 2014-2015 were targeted in the research. The reasons for excluding subjects from the PPS efficacy analysis were described in 102 trials out of 492 in the summary of new drug application documents, which was publicly disclosed after the drug's regulatory approval. The author extracted these reasons along with the numbers of the cases and the study characteristics of each clinical trial. Then, the direct comparison, univariate regression analysis, and multivariate regression analysis was carried out based on the exclusion rate. The study characteristics for which exclusion of subjects from the PPS efficacy analysis were frequently observed was multiregional clinical trials in study region; inhalant and external use in administration route; Anti-infective for systemic use; Respiratory system, Dermatologicals, and Nervous system in therapeutic drug under the Anatomical Therapeutic Chemical Classification. In the multivariate regression analysis, the clinical trial variables of inhalant, Respiratory system, or Dermatologicals were selected as study characteristics leading to a higher exclusion rate. The characteristics of the clinical trial that is likely to cause protocol deviations that will affect efficacy analysis were suggested. These studies should be considered for specific attention and priority observation in the trial protocol or its monitoring plan and execution, such as a clear description of inclusion/exclusion criteria in the protocol, development of training materials to site staff, and/or trial subjects as specific risk-alleviating measures.

  19. Realist explanatory theory building method for social epidemiology: a protocol for a mixed method multilevel study of neighbourhood context and postnatal depression.

    PubMed

    Eastwood, John G; Jalaludin, Bin B; Kemp, Lynn A

    2014-01-01

    A recent criticism of social epidemiological studies, and multi-level studies in particular has been a paucity of theory. We will present here the protocol for a study that aims to build a theory of the social epidemiology of maternal depression. We use a critical realist approach which is trans-disciplinary, encompassing both quantitative and qualitative traditions, and that assumes both ontological and hierarchical stratification of reality. We describe a critical realist Explanatory Theory Building Method comprising of an: 1) emergent phase, 2) construction phase, and 3) confirmatory phase. A concurrent triangulated mixed method multilevel cross-sectional study design is described. The Emergent Phase uses: interviews, focus groups, exploratory data analysis, exploratory factor analysis, regression, and multilevel Bayesian spatial data analysis to detect and describe phenomena. Abductive and retroductive reasoning will be applied to: categorical principal component analysis, exploratory factor analysis, regression, coding of concepts and categories, constant comparative analysis, drawing of conceptual networks, and situational analysis to generate theoretical concepts. The Theory Construction Phase will include: 1) defining stratified levels; 2) analytic resolution; 3) abductive reasoning; 4) comparative analysis (triangulation); 5) retroduction; 6) postulate and proposition development; 7) comparison and assessment of theories; and 8) conceptual frameworks and model development. The strength of the critical realist methodology described is the extent to which this paradigm is able to support the epistemological, ontological, axiological, methodological and rhetorical positions of both quantitative and qualitative research in the field of social epidemiology. The extensive multilevel Bayesian studies, intensive qualitative studies, latent variable theory, abductive triangulation, and Inference to Best Explanation provide a strong foundation for Theory Construction. The study will contribute to defining the role that realism and mixed methods can play in explaining the social determinants and developmental origins of health and disease.

  20. Effect of dietary intervention treatment on children with iron deficiency anemia in China: a meta-analysis.

    PubMed

    Sun, Jian; Zhang, Lei; Cui, Jing; Li, Shanshan; Lu, Hongting; Zhang, Yong; Li, Haiming; Sun, Jianping; Baloch, Zulqarnain

    2018-05-10

    Previous studies have shown beneficial effects of dietary approaches for iron deficiency anemia (IDA) control. This study was design to investigate the effect of dietary intervention treatment on children with iron deficiency anemia. We performed a systematic review of published dietary interventions effect on IDA treatment through meta-analysis. CBM, CNKI, Wanfang database, EMBASE, VIP, PubMed and Web of science database were searched to identify studies published between January, 1980 and December, 2016. Statistical analysis was performed by Revmen5.2 software. Initially we retrieved for 373 studies, and then 6 studies with a total of 676 individuals were included in the analysis according to the inclusion and exclusion criteria for meta-analysis. The overall pooled estimate of odds ratio [(OR), 95% confidence intervals (95% CI)] in the dietary intervention on children with iron deficiency anemia was 6.54 (95% CI: 3.48-12.31, Z = 5.82, p<0.001) and funnel plot is symmetric. Our meta-analysis suggested that dietary interventions are effective in improving the iron deficiency in children with iron deficiency anemia (IDA) and should be considered in the overall strategy of IDA management.

  1. Who's in and why? A typology of stakeholder analysis methods for natural resource management.

    PubMed

    Reed, Mark S; Graves, Anil; Dandy, Norman; Posthumus, Helena; Hubacek, Klaus; Morris, Joe; Prell, Christina; Quinn, Claire H; Stringer, Lindsay C

    2009-04-01

    Stakeholder analysis means many things to different people. Various methods and approaches have been developed in different fields for different purposes, leading to confusion over the concept and practice of stakeholder analysis. This paper asks how and why stakeholder analysis should be conducted for participatory natural resource management research. This is achieved by reviewing the development of stakeholder analysis in business management, development and natural resource management. The normative and instrumental theoretical basis for stakeholder analysis is discussed, and a stakeholder analysis typology is proposed. This consists of methods for: i) identifying stakeholders; ii) differentiating between and categorising stakeholders; and iii) investigating relationships between stakeholders. The range of methods that can be used to carry out each type of analysis is reviewed. These methods and approaches are then illustrated through a series of case studies funded through the Rural Economy and Land Use (RELU) programme. These case studies show the wide range of participatory and non-participatory methods that can be used, and discuss some of the challenges and limitations of existing methods for stakeholder analysis. The case studies also propose new tools and combinations of methods that can more effectively identify and categorise stakeholders and help understand their inter-relationships.

  2. Addressing the unit of analysis in medical care studies: a systematic review.

    PubMed

    Calhoun, Aaron W; Guyatt, Gordon H; Cabana, Michael D; Lu, Downing; Turner, David A; Valentine, Stacey; Randolph, Adrienne G

    2008-06-01

    We assessed the frequency that patients are incorrectly used as the unit of analysis among studies of physicians' patient care behavior in articles published in high impact journals. We surveyed 30 high-impact journals across 6 medical fields for articles susceptible to unit of analysis errors published from 1994 to 2005. Three reviewers independently abstracted articles using previously published criteria to determine the presence of analytic errors. One hundred fourteen susceptible articles were found published in 15 journals, 4 journals published the majority (71 of 114 or 62.3%) of studies, 40 were intervention studies, and 74 were noninterventional studies. The unit of analysis error was present in 19 (48%) of the intervention studies and 31 (42%) of the noninterventional studies (overall error rate 44%). The frequency of the error decreased between 1994-1999 (N = 38; 65% error) and 2000-2005 (N = 76; 33% error) (P = 0.001). Although the frequency of the error in published studies is decreasing, further improvement remains desirable.

  3. A regulation probability model-based meta-analysis of multiple transcriptomics data sets for cancer biomarker identification.

    PubMed

    Xie, Xin-Ping; Xie, Yu-Feng; Wang, Hong-Qiang

    2017-08-23

    Large-scale accumulation of omics data poses a pressing challenge of integrative analysis of multiple data sets in bioinformatics. An open question of such integrative analysis is how to pinpoint consistent but subtle gene activity patterns across studies. Study heterogeneity needs to be addressed carefully for this goal. This paper proposes a regulation probability model-based meta-analysis, jGRP, for identifying differentially expressed genes (DEGs). The method integrates multiple transcriptomics data sets in a gene regulatory space instead of in a gene expression space, which makes it easy to capture and manage data heterogeneity across studies from different laboratories or platforms. Specifically, we transform gene expression profiles into a united gene regulation profile across studies by mathematically defining two gene regulation events between two conditions and estimating their occurring probabilities in a sample. Finally, a novel differential expression statistic is established based on the gene regulation profiles, realizing accurate and flexible identification of DEGs in gene regulation space. We evaluated the proposed method on simulation data and real-world cancer datasets and showed the effectiveness and efficiency of jGRP in identifying DEGs identification in the context of meta-analysis. Data heterogeneity largely influences the performance of meta-analysis of DEGs identification. Existing different meta-analysis methods were revealed to exhibit very different degrees of sensitivity to study heterogeneity. The proposed method, jGRP, can be a standalone tool due to its united framework and controllable way to deal with study heterogeneity.

  4. Predicting the extent of heterogeneity in meta-analysis, using empirical data from the Cochrane Database of Systematic Reviews

    PubMed Central

    Turner, Rebecca M; Davey, Jonathan; Clarke, Mike J; Thompson, Simon G; Higgins, Julian PT

    2012-01-01

    Background Many meta-analyses contain only a small number of studies, which makes it difficult to estimate the extent of between-study heterogeneity. Bayesian meta-analysis allows incorporation of external evidence on heterogeneity, and offers advantages over conventional random-effects meta-analysis. To assist in this, we provide empirical evidence on the likely extent of heterogeneity in particular areas of health care. Methods Our analyses included 14 886 meta-analyses from the Cochrane Database of Systematic Reviews. We classified each meta-analysis according to the type of outcome, type of intervention comparison and medical specialty. By modelling the study data from all meta-analyses simultaneously, using the log odds ratio scale, we investigated the impact of meta-analysis characteristics on the underlying between-study heterogeneity variance. Predictive distributions were obtained for the heterogeneity expected in future meta-analyses. Results Between-study heterogeneity variances for meta-analyses in which the outcome was all-cause mortality were found to be on average 17% (95% CI 10–26) of variances for other outcomes. In meta-analyses comparing two active pharmacological interventions, heterogeneity was on average 75% (95% CI 58–95) of variances for non-pharmacological interventions. Meta-analysis size was found to have only a small effect on heterogeneity. Predictive distributions are presented for nine different settings, defined by type of outcome and type of intervention comparison. For example, for a planned meta-analysis comparing a pharmacological intervention against placebo or control with a subjectively measured outcome, the predictive distribution for heterogeneity is a log-normal (−2.13, 1.582) distribution, which has a median value of 0.12. In an example of meta-analysis of six studies, incorporating external evidence led to a smaller heterogeneity estimate and a narrower confidence interval for the combined intervention effect. Conclusions Meta-analysis characteristics were strongly associated with the degree of between-study heterogeneity, and predictive distributions for heterogeneity differed substantially across settings. The informative priors provided will be very beneficial in future meta-analyses including few studies. PMID:22461129

  5. Effect modification of FADS2 polymorphisms on the association between breastfeeding and intelligence: protocol for a collaborative meta-analysis

    PubMed Central

    Hartwig, Fernando Pires; Davies, Neil Martin; Horta, Bernardo Lessa; Victora, Cesar Gomes; Davey Smith, George

    2016-01-01

    Introduction Evidence from observational studies and randomised controlled trials suggests that breastfeeding is positively associated with IQ, possibly because breast milk is a source of long-chain polyunsaturated fatty acids. Different studies have detected gene-breastfeeding interactions involving FADS2 variants and intelligence. However, findings are inconsistent regarding the direction of such effect modification. Methods/design To clarify how FADS2 and breastfeeding interact in their association with IQ, we are conducting a consortium-based meta-analysis of independent studies. Results produced by each individual study using standardised analysis scripts and harmonised data will be used. Inclusion criteria: breastfeeding, IQ and either rs174575 or rs1535 polymorphisms available; and being of European ancestry. Exclusion criteria: twin studies; only poorly imputed genetic data available; or unavailability of proper ethics approval. Studies will be invited based on being known to have at least some of the required data, or suggested by participating studies as potentially eligible. This inclusive approach will favour achieving a larger sample size and be less prone to publication bias. Discussion Improving current understanding of FADS2-breastfeeding interaction may provide important biological insights regarding the importance of long-chain polyunsaturated fatty acids for the breastfeeding-IQ association. This meta-analysis will help to improve such knowledge by replicating earlier studies, conducting additional analysis and evaluating different sources of heterogeneity. Publishing this protocol will minimise the possibility of bias due to post hoc changes to the analysis protocol. PMID:27311901

  6. Association of obesity with hypertension and type 2 diabetes mellitus in India: A meta-analysis of observational studies

    PubMed Central

    Babu, Giridhara R; Murthy, G V S; Ana, Yamuna; Patel, Prital; Deepa, R; Neelon, Sara E Benjamin; Kinra, Sanjay; Reddy, K Srinath

    2018-01-01

    AIM To perform a meta-analysis of the association of obesity with hypertension and type 2 diabetes mellitus (T2DM) in India among adults. METHODS To conduct meta-analysis, we performed comprehensive, electronic literature search in the PubMed, CINAHL Plus, and Google Scholar. We restricted the analysis to studies with documentation of some measure of obesity namely; body mass index, waist-hip ratio, waist circumference and diagnosis of hypertension or diagnosis of T2DM. By obtaining summary estimates of all included studies, the meta-analysis was performed using both RevMan version 5 and “metan” command STATA version 11. Heterogeneity was measured by I2 statistic. Funnel plot analysis has been done to assess the study publication bias. RESULTS Of the 956 studies screened, 18 met the eligibility criteria. The pooled odds ratio between obesity and hypertension was 3.82 (95%CI: 3.39 to 4.25). The heterogeneity around this estimate (I2 statistic) was 0%, indicating low variability. The pooled odds ratio from the included studies showed a statistically significant association between obesity and T2DM (OR = 1.14, 95%CI: 1.04 to 1.24) with a high degree of variability. CONCLUSION Despite methodological differences, obesity showed significant, potentially plausible association with hypertension and T2DM in studies conducted in India. Being a modifiable risk factor, our study informs setting policy priority and intervention efforts to prevent debilitating complications. PMID:29359028

  7. Association of obesity with hypertension and type 2 diabetes mellitus in India: A meta-analysis of observational studies.

    PubMed

    Babu, Giridhara R; Murthy, G V S; Ana, Yamuna; Patel, Prital; Deepa, R; Neelon, Sara E Benjamin; Kinra, Sanjay; Reddy, K Srinath

    2018-01-15

    To perform a meta-analysis of the association of obesity with hypertension and type 2 diabetes mellitus (T2DM) in India among adults. To conduct meta-analysis, we performed comprehensive, electronic literature search in the PubMed, CINAHL Plus, and Google Scholar. We restricted the analysis to studies with documentation of some measure of obesity namely; body mass index, waist-hip ratio, waist circumference and diagnosis of hypertension or diagnosis of T2DM. By obtaining summary estimates of all included studies, the meta-analysis was performed using both RevMan version 5 and "metan" command STATA version 11. Heterogeneity was measured by I 2 statistic. Funnel plot analysis has been done to assess the study publication bias. Of the 956 studies screened, 18 met the eligibility criteria. The pooled odds ratio between obesity and hypertension was 3.82 (95%CI: 3.39 to 4.25). The heterogeneity around this estimate (I2 statistic) was 0%, indicating low variability. The pooled odds ratio from the included studies showed a statistically significant association between obesity and T2DM (OR = 1.14, 95%CI: 1.04 to 1.24) with a high degree of variability. Despite methodological differences, obesity showed significant, potentially plausible association with hypertension and T2DM in studies conducted in India. Being a modifiable risk factor, our study informs setting policy priority and intervention efforts to prevent debilitating complications.

  8. A Comparison of Human Narrative Coding of Redemption and Automated Linguistic Analysis for Understanding Life Stories.

    PubMed

    Weston, Sara J; Cox, Keith S; Condon, David M; Jackson, Joshua J

    2016-10-01

    The majority of life narrative research is performed using trained human coders. In contrast, automated linguistic analysis is oft employed in the study of verbal behaviors. These two methodological approaches are directly compared to determine the utility of automated linguistic analysis for the study of life narratives. In a study of in-person interviews (N = 158) and a second study of life stories collected online (N = 242), redemption scores are compared to the output of the Linguistic Inquiry and Word Count (Pennebaker, Francis & Booth, 2001). Additionally, patterns of language are found using exploratory principal components analysis. In both studies, redemption scores are modestly correlated with some LIWC categories and unassociated with the components. Patterns of language do not replicate across samples, indicating that the structure of language does not extend to a broader population. Redemption scores and linguistic components are independent predictors of life satisfaction up to 3 years later. These studies converge on the finding that human-coded redemption and automated linguistic analysis are complementary and nonredundant methods of analyzing life narratives, and considerations for the study of life narratives are discussed. © 2015 Wiley Periodicals, Inc.

  9. Body mass index and risk of BPH: a meta-analysis.

    PubMed

    Wang, S; Mao, Q; Lin, Y; Wu, J; Wang, X; Zheng, X; Xie, L

    2012-09-01

    Epidemiological studies have reported conflicting results relating obesity to BPH. A meta-analysis of cohort and case-control studies was conducted to pool the risk estimates of the association between obesity and BPH. Eligible studies were retrieved by both computer searches and review of references. We analyzed abstracted data with random effects models to obtain the summary risk estimates. Dose-response meta-analysis was performed for studies reporting categorical risk estimates for a series of exposure levels. A total of 19 studies met the inclusion criteria of the meta-analysis. Positive association with body mass index (BMI) was observed in BPH and lower urinary tract symptoms (LUTS) combined group (odds ratio=1.27, 95% confidence intervals 1.05-1.53). In subgroup analysis, BMI exhibited a positive dose-response relationship with BPH/LUTS in population-based case-control studies and a marginal positive association was observed between risk of BPH and increased BMI. However, no association between BPH/LUTS and BMI was observed in other subgroups stratified by study design, geographical region or primary outcome. The overall current literatures suggested that BMI was associated with increased risk of BPH. Further efforts should be made to confirm these findings and clarify the underlying biological mechanisms.

  10. Simplified method for the transverse bending analysis of twin celled concrete box girder bridges

    NASA Astrophysics Data System (ADS)

    Chithra, J.; Nagarajan, Praveen; S, Sajith A.

    2018-03-01

    Box girder bridges are one of the best options for bridges with span more than 25 m. For the study of these bridges, three-dimensional finite element analysis is the best suited method. However, performing three-dimensional analysis for routine design is difficult as well as time consuming. Also, software used for the three-dimensional analysis are very expensive. Hence designers resort to simplified analysis for predicting longitudinal and transverse bending moments. Among the many analytical methods used to find the transverse bending moments, SFA is the simplest and widely used in design offices. Results from simplified frame analysis can be used for the preliminary analysis of the concrete box girder bridges.From the review of literatures, it is found that majority of the work done using SFA is restricted to the analysis of single cell box girder bridges. Not much work has been done on the analysis multi-cell concrete box girder bridges. In this present study, a double cell concrete box girder bridge is chosen. The bridge is modelled using three- dimensional finite element software and the results are then compared with the simplified frame analysis. The study mainly focuses on establishing correction factors for transverse bending moment values obtained from SFA.

  11. Dynamic stress analysis of smooth and notched fiber composite flexural specimens

    NASA Technical Reports Server (NTRS)

    Murthy, P. L. N.; Chamis, C. C.

    1984-01-01

    A detailed analysis of the dynamic stress field in smooth and notched fiber composite (Charpy-type) specimens is reported in this paper. The analysis is performed with the aid of the direct transient response analysis solution sequence of MSC/NASTRAN. Three unidirectional composites were chosen for the study. They are S-Glass/Epoxy, Kevlar/Epoxy and T-300/Epoxy composite systems. The specimens are subjected to an impact load which is modeled as a triangular impulse with a maximum of 2000 lb and a duration of 1 ms. The results are compared with those of static analysis of the specimens subjected to a peak load of 2000 lb. For the geometry and type of materials studied, the static analysis results gave close conservative estimates for the dynamic stresses. Another interesting inference from the study is that the impact induced effects are felt by S-Glass/Epoxy specimens sooner than Kevlar/Epoxy or T-300/Epoxy specimens.

  12. Transmission Planning Analysis Tool

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    2015-06-23

    Developed to solve specific problem: Assist transmission planning for regional transfers in interconnected power systems. This work was originated in a study for the U.S. Department of State, to recommend transmission reinforcements for the Central American regional system that interconnects 6 countries. Transmission planning analysis is currently performed by engineers with domainspecific and systemspecific knowledge without a unique methodology. The software codes of this disclosure assists engineers by defining systematic analysis procedures to help identify weak points and make decisions on transmission planning of regional interconnected power systems. Transmission Planning Analysis Tool groups PSS/E results of multiple AC contingency analysismore » and voltage stability analysis and QV analysis of many scenarios of study and arrange them in a systematic way to aid power system planning engineers or transmission operators in effective decision]making process or in the off]line study environment.« less

  13. Conducting a narrative analysis.

    PubMed

    Emden, C

    1998-07-01

    This paper describes the process of narrative analysis as undertaken within a nursing study on scholars and scholarship. If follows an earlier paper titled: Theoretical perspectives on narrative inquiry that described the influencing ideas of Bruner (1987) and Roof (1994) upon the same study. Analysis procedures are described here in sufficient detail for other researchers wishing to implement a similar approach to do so. The process as described has two main components: (A) strategies of 'core story creation' and 'employment'; and (B) issues and dilemmas of narrative analysis, especially relating to rigour. The ideas of Polkinghorne (1988), Mishler (1986), and Labov (in Mishler 1986a) are introduced in so far as they impinge upon the analysis process. These relate especially to the development of key terms, and to the analysis strategies of core story creation and employment. Outcomes of the study in question are termed 'Signposting the lived-world of scholarship'.

  14. Caffeine intake from coffee or tea and cognitive disorders: a meta-analysis of observational studies.

    PubMed

    Kim, Young-Seok; Kwak, Sang Mi; Myung, Seung-Kwon

    2015-01-01

    Observational epidemiological studies such as cross-sectional, case-control, and cohort studies have reported inconsistent findings regarding the association between caffeine intake from coffee or tea and the risk of cognitive disorders such as dementia, Alzheimer's disease, cognitive impairment, and cognitive decline. We searched PubMed and EMBASE in September 2014. Three evaluators independently extracted and reviewed articles, based on predetermined selection criteria. Out of 293 articles identified through the search and bibliographies of relevant articles, 20 epidemiological studies from 19 articles, which involved 31,479 participants (8,398 in six cross-sectional studies, 4,601 in five case-control studies, and 19,918 in nine cohort studies), were included in the final analysis. The pooled odds ratio (OR) or relative risk (RR) of caffeine intake from coffee or tea for cognitive disorders (dementia, Alzheimer's disease, cognitive impairment, and cognitive decline) was 0.82 (95% confidence interval [CI], 0.67-1.01, I² = 63.2%) in a random-effects meta-analysis. In the subgroup meta-analysis by caffeine sources, the summary OR or RR of coffee intake was 0.83 (95% CI, 0.70-0.98; I² = 44.8%). However, in the subgroup meta-analysis by study design, the summary estimates (RR or OR) of coffee intake for cognitive disorders were 0.70 (95% CI, 0.50-0.98; I² = 42.0%) for cross-sectional studies, 0.82 (95% CI, 0.55-1.24; I² = 33.4%) for case-control studies, and 0.90 (95% CI, 0.59-1.36; I² = 60.0%) for cohort studies. This meta-analysis found that caffeine intake from coffee or tea was not associated with the risk of cognitive disorders.

  15. Large Deployable Reflector (LDR) feasibility study update

    NASA Technical Reports Server (NTRS)

    Alff, W. H.; Banderman, L. W.

    1983-01-01

    In 1982 a workshop was held to refine the science rationale for large deployable reflectors (LDR) and develop technology requirements that support the science rationale. At the end of the workshop, a set of LDR consensus systems requirements was established. The subject study was undertaken to update the initial LDR study using the new systems requirements. The study included mirror materials selection and configuration, thermal analysis, structural concept definition and analysis, dynamic control analysis and recommendations for further study. The primary emphasis was on the dynamic controls requirements and the sophistication of the controls system needed to meet LDR performance goals.

  16. The role of environmental heterogeneity in meta-analysis of gene-environment interactions with quantitative traits.

    PubMed

    Li, Shi; Mukherjee, Bhramar; Taylor, Jeremy M G; Rice, Kenneth M; Wen, Xiaoquan; Rice, John D; Stringham, Heather M; Boehnke, Michael

    2014-07-01

    With challenges in data harmonization and environmental heterogeneity across various data sources, meta-analysis of gene-environment interaction studies can often involve subtle statistical issues. In this paper, we study the effect of environmental covariate heterogeneity (within and between cohorts) on two approaches for fixed-effect meta-analysis: the standard inverse-variance weighted meta-analysis and a meta-regression approach. Akin to the results in Simmonds and Higgins (), we obtain analytic efficiency results for both methods under certain assumptions. The relative efficiency of the two methods depends on the ratio of within versus between cohort variability of the environmental covariate. We propose to use an adaptively weighted estimator (AWE), between meta-analysis and meta-regression, for the interaction parameter. The AWE retains full efficiency of the joint analysis using individual level data under certain natural assumptions. Lin and Zeng (2010a, b) showed that a multivariate inverse-variance weighted estimator retains full efficiency as joint analysis using individual level data, if the estimates with full covariance matrices for all the common parameters are pooled across all studies. We show consistency of our work with Lin and Zeng (2010a, b). Without sacrificing much efficiency, the AWE uses only univariate summary statistics from each study, and bypasses issues with sharing individual level data or full covariance matrices across studies. We compare the performance of the methods both analytically and numerically. The methods are illustrated through meta-analysis of interaction between Single Nucleotide Polymorphisms in FTO gene and body mass index on high-density lipoprotein cholesterol data from a set of eight studies of type 2 diabetes. © 2014 WILEY PERIODICALS, INC.

  17. Influence of control group therapy on the benefit from dose-dense chemotherapy in early breast cancer: a systemic review and meta-analysis.

    PubMed

    Goldvaser, Hadar; Majeed, Habeeb; Ribnikar, Domen; Šeruga, Boštjan; Ocaña, Alberto; Cescon, David W; Amir, Eitan

    2018-06-01

    Results from clinical trials of adjuvant dose-dense chemotherapy in patients with breast cancer are inconsistent. A systematic search of MEDLINE identified studies comparing the efficacy of dose-dense adjuvant chemotherapy to a standard treatment. The primary analysis included studies that used identical regimens in the experimental and control groups, but varied only dose density. A secondary analysis included studies that used either different drugs or doses in the experimental and the control groups. Hazard ratios (HRs) and 95% confidence intervals were computed for disease-free survival (DFS) and overall survival (OS) and pooled in a meta-analysis. Subgroup analyses and meta-regression explored drug schedules utilized in control groups and the influence of clinicopathologic variables on benefit from dose-dense therapy. The primary analysis included 5 studies comprising 9819 patients while the secondary analysis included 6 studies comprising 9679 patients. Dose-dense treatment significantly improved DFS (HR 0.85, p < 0.001) and OS (HR 0.86, p = 0.008) in the primary analysis. Similar results were observed in the secondary analysis. Dose-dense schedule was important primarily in studies utilizing paclitaxel every 3 weeks as the control group (interaction p = 0.04 for DFS interaction p = 0.001 for OS). A significantly greater relative magnitude of benefit was observed in pre-menopausal women and those with nodal involvement, but there was no influence of hormone receptor status on results. Adjuvant dose-dense regimens improve breast cancer outcomes. It remains uncertain whether the observed benefit reflects the impact of dose density or the inferiority of paclitaxel every 3 weeks as a control group.

  18. Poverty in Latin America: A Critical Analysis of Three Studies.

    ERIC Educational Resources Information Center

    Boltvinik, Julio

    1996-01-01

    Critically evaluates the methodologies used in three recent studies on poverty in Latin America. Maintains that some studies measure the relative nature of nutritional poverty while others record the absolute nature of nutritional poverty (physical survival). Includes a comparative analysis of the studies' results. (MJP)

  19. Impact of tailored feedback in assessment of communication skills for medical students.

    PubMed

    Uhm, Seilin; Lee, Gui H; Jin, Jeong K; Bak, Yong I; Jeoung, Yeon O; Kim, Chan W

    2015-01-01

    Finding out the effective ways of teaching and assessing communication skills remain a challenging part of medication education. This study aims at exploring the usefulness and effectiveness of having additional feedback using qualitative analysis in assessment of communication skills in undergraduate medical training. We also determined the possibilities of using qualitative analysis in developing tailored strategies for improvement in communication skills training. This study was carried out on medical students (n=87) undergoing their final year clinical performance examination on communication skills using standardized patient by video-recording and transcribing their performances. Video-recordings of 26 students were randomly selected for qualitative analysis, and additional feedback was provided. We assessed the level of acceptance of communication skills scores between the study and nonstudy group and within the study group, before and after receiving feedback based on qualitative analysis. There was a statistically significant increase in the level of acceptance of feedback after delivering additional feedback using qualitative analysis, where the percentage of agreement with feedback increased from 15.4 to 80.8% (p<0.001). Incorporating feedback based on qualitative analysis for communication skills assessment gives essential information for medical students to learn and self-reflect, which could potentially lead to improved communication skills. As evident from our study, feedback becomes more meaningful and effective with additional feedback using qualitative analysis.

  20. Impact of tailored feedback in assessment of communication skills for medical students

    PubMed Central

    Uhm, Seilin; Lee, Gui H.; Jin, Jeong K.; Bak, Yong I.; Jeoung, Yeon O.; Kim, Chan W.

    2015-01-01

    Background Finding out the effective ways of teaching and assessing communication skills remain a challenging part of medication education. This study aims at exploring the usefulness and effectiveness of having additional feedback using qualitative analysis in assessment of communication skills in undergraduate medical training. We also determined the possibilities of using qualitative analysis in developing tailored strategies for improvement in communication skills training. Methods This study was carried out on medical students (n=87) undergoing their final year clinical performance examination on communication skills using standardized patient by video-recording and transcribing their performances. Video-recordings of 26 students were randomly selected for qualitative analysis, and additional feedback was provided. We assessed the level of acceptance of communication skills scores between the study and nonstudy group and within the study group, before and after receiving feedback based on qualitative analysis. Results There was a statistically significant increase in the level of acceptance of feedback after delivering additional feedback using qualitative analysis, where the percentage of agreement with feedback increased from 15.4 to 80.8% (p<0.001). Conclusions Incorporating feedback based on qualitative analysis for communication skills assessment gives essential information for medical students to learn and self-reflect, which could potentially lead to improved communication skills. As evident from our study, feedback becomes more meaningful and effective with additional feedback using qualitative analysis. PMID:26154864

  1. A Methodology for the Development of RESTful Semantic Web Services for Gene Expression Analysis

    PubMed Central

    Guardia, Gabriela D. A.; Pires, Luís Ferreira; Vêncio, Ricardo Z. N.; Malmegrim, Kelen C. R.; de Farias, Cléver R. G.

    2015-01-01

    Gene expression studies are generally performed through multi-step analysis processes, which require the integrated use of a number of analysis tools. In order to facilitate tool/data integration, an increasing number of analysis tools have been developed as or adapted to semantic web services. In recent years, some approaches have been defined for the development and semantic annotation of web services created from legacy software tools, but these approaches still present many limitations. In addition, to the best of our knowledge, no suitable approach has been defined for the functional genomics domain. Therefore, this paper aims at defining an integrated methodology for the implementation of RESTful semantic web services created from gene expression analysis tools and the semantic annotation of such services. We have applied our methodology to the development of a number of services to support the analysis of different types of gene expression data, including microarray and RNASeq. All developed services are publicly available in the Gene Expression Analysis Services (GEAS) Repository at http://dcm.ffclrp.usp.br/lssb/geas. Additionally, we have used a number of the developed services to create different integrated analysis scenarios to reproduce parts of two gene expression studies documented in the literature. The first study involves the analysis of one-color microarray data obtained from multiple sclerosis patients and healthy donors. The second study comprises the analysis of RNA-Seq data obtained from melanoma cells to investigate the role of the remodeller BRG1 in the proliferation and morphology of these cells. Our methodology provides concrete guidelines and technical details in order to facilitate the systematic development of semantic web services. Moreover, it encourages the development and reuse of these services for the creation of semantically integrated solutions for gene expression analysis. PMID:26207740

  2. A Methodology for the Development of RESTful Semantic Web Services for Gene Expression Analysis.

    PubMed

    Guardia, Gabriela D A; Pires, Luís Ferreira; Vêncio, Ricardo Z N; Malmegrim, Kelen C R; de Farias, Cléver R G

    2015-01-01

    Gene expression studies are generally performed through multi-step analysis processes, which require the integrated use of a number of analysis tools. In order to facilitate tool/data integration, an increasing number of analysis tools have been developed as or adapted to semantic web services. In recent years, some approaches have been defined for the development and semantic annotation of web services created from legacy software tools, but these approaches still present many limitations. In addition, to the best of our knowledge, no suitable approach has been defined for the functional genomics domain. Therefore, this paper aims at defining an integrated methodology for the implementation of RESTful semantic web services created from gene expression analysis tools and the semantic annotation of such services. We have applied our methodology to the development of a number of services to support the analysis of different types of gene expression data, including microarray and RNASeq. All developed services are publicly available in the Gene Expression Analysis Services (GEAS) Repository at http://dcm.ffclrp.usp.br/lssb/geas. Additionally, we have used a number of the developed services to create different integrated analysis scenarios to reproduce parts of two gene expression studies documented in the literature. The first study involves the analysis of one-color microarray data obtained from multiple sclerosis patients and healthy donors. The second study comprises the analysis of RNA-Seq data obtained from melanoma cells to investigate the role of the remodeller BRG1 in the proliferation and morphology of these cells. Our methodology provides concrete guidelines and technical details in order to facilitate the systematic development of semantic web services. Moreover, it encourages the development and reuse of these services for the creation of semantically integrated solutions for gene expression analysis.

  3. Feasibility study for biomass power plants in Thailand. Volume 2. appendix: Detailed financial analysis results. Export trade information

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    This study, conducted by Black & Veatch, was funded by the U.S. Trade and Development Agency. The report presents a technical and commercial analysis for the development of three nearly identical electricity generating facilities (biomass steam power plants) in the towns of Chachgoengsao, Suphan Buri, and Pichit in Thailand. Volume 2 of the study contains the following appendix: Detailed Financial Analysis Results.

  4. Multifractal detrended Cross Correlation Analysis of Foreign Exchange and SENSEX fluctuation in Indian perspective

    NASA Astrophysics Data System (ADS)

    Dutta, Srimonti; Ghosh, Dipak; Chatterjee, Sucharita

    2016-12-01

    The manuscript studies autocorrelation and cross correlation of SENSEX fluctuations and Forex Exchange Rate in respect to Indian scenario. Multifractal detrended fluctuation analysis (MFDFA) and multifractal detrended cross correlation analysis (MFDXA) were employed to study the correlation between the two series. It was observed that the two series are strongly cross correlated. The change of degree of cross correlation with time was studied and the results are interpreted qualitatively.

  5. Commerce Lab: Mission analysis. Payload integration study

    NASA Technical Reports Server (NTRS)

    Marvin, G. D.

    1984-01-01

    The objectives of the commerce lab mission analysis and payload integration study are discussed. A mission model which accommodates commercial users and provides a basic data base for future mission planning is described. The data bases developed under this study include: (1) user requirements; (2) apparatus capabilities and availabilities; and (3) carrier capabilities. These data bases are synthesized in a trades and analysis phase along with the STS flight opportunities. Optimum missions are identified.

  6. The Joint Chiefs of Staff and National Policy, 1977-1980

    DTIC Science & Technology

    2015-01-01

    advice on program, budget, and force structure issues, allowing him augmented staff support in the studies, analysis, and gaming area, as appropriate... Gaming Agency (SAGA) to provide an assessment of US capabilities to meet contingencies in the Middle East- Persian Gulf. As this study was being...ongoing analysis by the JCS Studies, Analysis, and Gaming Agency (SAGA), a Soviet advance southward toward Tehran in the wake of simultaneous air and

  7. The Sensitivity of the Incidence of Poverty to Different Measures of Income: School-Aged Children and Families. The Measure of Poverty, Technical Paper XVII.

    ERIC Educational Resources Information Center

    Coe, Richard D.; And Others

    This study is a two-part analysis aimed at determining what differences occur in the incidence of poverty when different definitions of income are employed and when the time frame of analysis is changed. The first part of the analysis concentrates on school-aged children, while the second part studies families. The study is based on data from the…

  8. Economic analysis of the health impacts of housing improvement studies: a systematic review.

    PubMed

    Fenwick, Elisabeth; Macdonald, Catriona; Thomson, Hilary

    2013-10-01

    Economic evaluation of public policies has been advocated but rarely performed. Studies from a systematic review of the health impacts of housing improvement included data on costs and some economic analysis. Examination of these data provides an opportunity to explore the difficulties and the potential for economic evaluation of housing. Data were extracted from all studies included in the systematic review of housing improvement which had reported costs and economic analysis (n=29/45). The reported data were assessed for their suitability to economic evaluation. Where an economic analysis was reported the analysis was described according to pre-set definitions of various types of economic analysis used in the field of health economics. 25 studies reported cost data on the intervention and/or benefits to the recipients. Of these, 11 studies reported data which was considered amenable to economic evaluation. A further four studies reported conducting an economic evaluation. Three of these studies presented a hybrid 'balance sheet' approach and indicated a net economic benefit associated with the intervention. One cost-effectiveness evaluation was identified but the data were unclearly reported; the cost-effectiveness plane suggested that the intervention was more costly and less effective than the status quo. Future studies planning an economic evaluation need to (i) make best use of available data and (ii) ensure that all relevant data are collected. To facilitate this, economic evaluations should be planned alongside the intervention with input from health economists from the outset of the study. When undertaken appropriately, economic evaluation provides the potential to make significant contributions to housing policy.

  9. Association between depression and periodontitis: a systematic review and meta-analysis.

    PubMed

    Araújo, Milena Moreira; Martins, Carolina Castro; Costa, Lidiane Cristina Machado; Cota, Luís Otávio Miranda; Faria, Rodrigo Lamounier Araújo Melo; Cunha, Fabiano Araújo; Costa, Fernando Oliveira

    2016-03-01

    The aim of this systematic review and meta-analysis was to assess the scientific evidence on the association between depression and periodontitis. An electronic search was conducted in three databases until October 2015 (PROSPERO-CRD42014006451). Hand searches and grey literature were also included. Search retrieved 423 potentially studies. Two independent reviewers selected the studies, extracted data and assessed risk bias through a modified version of Newcastle-Ottawa scale. Meta-analysis was performed for the presence/absence of periodontitis (dichotomic). Summary effect measures and odds ratio (OR) 95% CI were calculated. After selecting the studies, 15 were included in the systematic review (eight cross-sectional, six case-control and one cohort study). Six studies reported that depression was associated with periodontitis, whereas nine studies did not. The majority of studies had low risk of bias by methodological quality assessment. Meta-analysis of seven cross-sectional studies showed no significant association between depression and periodontitis (OR = 1.03, 95% CI = 0.75-1.41). Findings from the present systematic review showed a great heterogeneity among the studies and the summary effect measure of the meta-analysis cannot affirm an association between depression and periodontitis. Future studies with different designs in distinct populations should be conducted to investigate this association. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Low circulating ghrelin levels in women with polycystic ovary syndrome: a systematic review and meta-analysis

    PubMed Central

    Gao, Tian; Wu, Lang; Chang, Fuhou; Cao, Guifang

    2016-01-01

    Although numerous, human subject studies evaluating the relationship between circulating ghrelin levels and polycystic ovary syndrome (PCOS) risk have yielded inconsistent findings. We aimed to quantitatively assess the association by summarizing all available evidence from human subject studies. The PubMed and Web of Science databases were searched up to February 2015 for eligible studies. Studies were eligible if they reported circulating ghrelin levels in women with PCOS and healthy women controls. A fixed or random-effects model was used to pool risk estimations. Twenty studies including 894 PCOS patients and 574 controls were included in the meta-analysis. The studies had fair methodological quality. The pooling analysis of all available studies revealed that ghrelin levels were significantly lower in PCOS patients than in controls, with standardized mean difference of −0.40 (95% CI: −0.73, −0.08). The significant association persisted in many subgroup strata. However, the heterogeneity across studies was considerable and not eliminated in subgroup analyses. Meta-regression analysis further suggested that the heterogeneity might be relevant to variability in study location, PCOS relevant factors like HOMA-IR ratio, as well as other factors not assessed. In conclusion, our meta-analysis suggested that ghrelin levels were significantly lower in PCOS patients than in controls. Further studies with large sample sizes are warranted to replicate our findings. PMID:26607017

  11. Vitamin D and depression: a systematic review and meta-analysis comparing studies with and without biological flaws.

    PubMed

    Spedding, Simon

    2014-04-11

    Efficacy of Vitamin D supplements in depression is controversial, awaiting further literature analysis. Biological flaws in primary studies is a possible reason meta-analyses of Vitamin D have failed to demonstrate efficacy. This systematic review and meta-analysis of Vitamin D and depression compared studies with and without biological flaws. The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The literature search was undertaken through four databases for randomized controlled trials (RCTs). Studies were critically appraised for methodological quality and biological flaws, in relation to the hypothesis and study design. Meta-analyses were performed for studies according to the presence of biological flaws. The 15 RCTs identified provide a more comprehensive evidence-base than previous systematic reviews; methodological quality of studies was generally good and methodology was diverse. A meta-analysis of all studies without flaws demonstrated a statistically significant improvement in depression with Vitamin D supplements (+0.78 CI +0.24, +1.27). Studies with biological flaws were mainly inconclusive, with the meta-analysis demonstrating a statistically significant worsening in depression by taking Vitamin D supplements (-1.1 CI -0.7, -1.5). Vitamin D supplementation (≥800 I.U. daily) was somewhat favorable in the management of depression in studies that demonstrate a change in vitamin levels, and the effect size was comparable to that of anti-depressant medication.

  12. Sequence analysis to assess labour market participation following vocational rehabilitation: an observational study among patients sick-listed with low back pain from a randomised clinical trial in Denmark.

    PubMed

    Lindholdt, Louise; Labriola, Merete; Nielsen, Claus Vinther; Horsbøl, Trine Allerslev; Lund, Thomas

    2017-07-20

    The return-to-work (RTW) process after long-term sickness absence is often complex and long and implies multiple shifts between different labour market states for the absentee. Standard methods for examining RTW research typically rely on the analysis of one outcome measure at a time, which will not capture the many possible states and transitions the absentee can go through. The purpose of this study was to explore the potential added value of sequence analysis in supplement to standard regression analysis of a multidisciplinary RTW intervention among patients with low back pain (LBP). The study population consisted of 160 patients randomly allocated to either a hospital-based brief or a multidisciplinary intervention. Data on labour market participation following intervention were obtained from a national register and analysed in two ways: as a binary outcome expressed as active or passive relief at a 1-year follow-up and as four different categories for labour market participation. Logistic regression and sequence analysis were performed. The logistic regression analysis showed no difference in labour market participation for patients in the two groups after 1 year. Applying sequence analysis showed differences in subsequent labour market participation after 2 years after baseline in favour of the brief intervention group versus the multidisciplinary intervention group. The study indicated that sequence analysis could provide added analytical value as a supplement to traditional regression analysis in prospective studies of RTW among patients with LBP. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. Prevalence of Orofacial Clefts among Live Births in China: A Systematic Review and Meta-Analysis.

    PubMed

    Wang, Mengying; Yuan, Yuan; Wang, Zifan; Liu, Dongjing; Wang, Zhuqing; Sun, Feng; Wang, Ping; Zhu, Hongping; Li, Jing; Wu, Tao; Beaty, Terri H

    2017-07-17

    Orofacial clefts (OFCs) are common human birth defects in China. However, studies on the prevalence of OFCs present inconsistent results. The overall prevalence and geographic distribution of OFCs are poorly described in China. Thus, we conducted a systematic review and meta-analysis to estimate the prevalence of OFCs. The systematic review and meta-analysis were conducted on the basis of an established protocol (PROSPERO 2015: CRD42015030198). We systematically searched for articles in four electronic databases, including Embase, PubMed, Wanfang Database, and China National Knowledge Infrastructure (CNKI) to identify relevant studies about prevalence of OFCs in China. Meta-analysis, including subgroup analysis, was conducted to estimate the pooled prevalence. A total of 41 studies published between 1986 and 2015 were included in our analysis. The sample size ranged from 2,586 to 4,611,808 live births. The random-effects model of meta-analysis showed that the overall prevalence of OFCs in China was 1.4 per 1000 live births (95% confidence interval [CI], 1.1-1.7). In subgroup analysis based on geographic regions, we found that OFC prevalence in Southwest (2.3 per 1000 live births, 95% CI, 1.1-4.7) was higher than that in other regions of China. There were no significant time trends of OFCs during the study period (p-value = 0.47). The overall prevalence of OFCs in China was 1.4 per 1000 live births. No significant secular trend of prevalence has been found in this analysis. Further studies need to be conducted to explore the etiology of OFC to better control the risk of this common birth defect. Birth Defects Research 109:1011-1019, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  14. Meta-analysis of expression and function of neprilysin in Alzheimer's disease.

    PubMed

    Zhang, Huifeng; Liu, Dan; Wang, Yixing; Huang, Huanhuan; Zhao, Yujia; Zhou, Hui

    2017-09-14

    Neprilysin (NEP) is one of the most important Aβ-degrading enzymes, and its expression and activity in Alzheimer's brain have been widely reported, but the results remain debatable. Thus, the meta-analysis was performed to elucidate the role of NEP in Alzheimer's disease (AD). The relevant case-control or cohort studies were retrieved according to our inclusion/exclusion criteria. Six studies with 123 controls and 141 AD cases, seven studies with 102 controls and 90 AD cases, and four studies with 93 controls and 132 AD cases were included in meta-analysis of NEP's protein, mRNA, and enzyme activity respectively. We conducted Meta regression to detect the sources of heterogeneity and further performed cumulative meta-analysis or subgroup analysis. Our meta-analysis revealed a significantly lower level of NEP mRNA (SMD=-0.44, 95%CI: -0.87, -0.00, p=0.049) in AD cases than in non-AD cases, and such pattern was not altered over time in the cumulative meta-analysis. However, the decrease of NEP protein (SMD=-0.18, 95%CI: -0.62, 0.25) and enzyme activity (SMD=-0.35, 95%CI: -1.03, 0.32) in AD cases did not pass the significance check, while the cumulative meta-analysis by average age showed the pooled effect became insignificant as adding the studies with younger subjects, which indicates that the protein expression and enzyme activity of NEP in the cortex are affected by age. Therefore, the present meta-analysis suggests the need of further investigation of roles of NEP in AD pathogenesis and treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Data Envelopment Analysis: Measurement of Educational Efficiency in Texas

    ERIC Educational Resources Information Center

    Carter, Lacy

    2012-01-01

    The purpose of this study was to examine the efficiency of Texas public school districts through Data Envelopment Analysis. The Data Envelopment Analysis estimation method calculated and assigned efficiency scores to each of the 931 school districts considered in the study. The efficiency scores were utilized in two phases. First, the school…

  16. The Risky Shift in Policy Decision Making: A Comparative Analysis

    ERIC Educational Resources Information Center

    Wilpert, B.; And Others

    1976-01-01

    Based on analysis of data on 432 decision-makers from around the world, this study examines the decision-making phenomenon that individuals tend to move toward riskier decisions after group discussion. Findings of the analysis contradicted earlier studies, showing a consistent shift toward greater risk avoidance. Available from Elsevier Scientific…

  17. Gender Differences in Academic Self-Efficacy: A Meta-Analysis

    ERIC Educational Resources Information Center

    Huang, Chiungjung

    2013-01-01

    A meta-analysis of 187 studies containing 247 independent studies (N = 68,429) on gender differences in academic self-efficacy identified an overall effect size of 0.08, with a small difference favoring males. Moderator analysis demonstrated that content domain was a significant moderator in explaining effect size variation. Females displayed…

  18. Mining Mineral Aggregates in Urban Areas.

    ERIC Educational Resources Information Center

    Thomson, Robert D.

    This study can be used in a geographic research methods course to show how nearest-neighbor analysis and regression analysis can be used to study various aspects of land use. An analysis of the sand, gravel, and crushed stone industry in three urban areas of Pennsylvania, Massachusetts, and Florida illustrates the locational problems faced by…

  19. Q-Type Factor Analysis of Healthy Aged Men.

    ERIC Educational Resources Information Center

    Kleban, Morton H.

    Q-type factor analysis was used to re-analyze baseline data collected in 1957, on 47 men aged 65-91. Q-type analysis is the use of factor methods to study persons rather than tests. Although 550 variables were originally studied involving psychiatry, medicine, cerebral metabolism and chemistry, personality, audiometry, dichotic and diotic memory,…

  20. Coherence Motion Perception in Developmental Dyslexia: A Meta-Analysis of Behavioral Studies

    ERIC Educational Resources Information Center

    Benassi, Mariagrazia; Simonelli, Letizia; Giovagnoli, Sara; Bolzani, Roberto

    2010-01-01

    The magnitude of the association between developmental dyslexia (DD) and motion sensitivity is evaluated in 35 studies, which investigated coherence motion perception in DD. A first analysis is conducted on the differences between DD groups and age-matched control (C) groups. In a second analysis, the relationship between motion coherence…

  1. Comparing Active Pediatric Obesity Treatments Using Meta-Analysis

    ERIC Educational Resources Information Center

    Gilles, Allyson; Cassano, Michael; Shepherd, Elizabeth J.; Higgins, Diana; Hecker, Jeffrey E.; Nangle, Douglas W.

    2008-01-01

    The current meta-analysis reviews research on the treatment of pediatric obesity focusing on studies that have been published since 1994. Eleven studies (22 comparisons, 115 effect sizes, N = 447) were included in the present meta-analysis. Results indicated that comprehensive behavioral interventions may be improved in at least two ways:…

  2. Quantitative Data Analysis--In the Graduate Curriculum

    ERIC Educational Resources Information Center

    Albers, Michael J.

    2017-01-01

    A quantitative research study collects numerical data that must be analyzed to help draw the study's conclusions. Teaching quantitative data analysis is not teaching number crunching, but teaching a way of critical thinking for how to analyze the data. The goal of data analysis is to reveal the underlying patterns, trends, and relationships of a…

  3. 45 CFR 307.15 - Approval of advance planning documents for computerized support enforcement systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... feasibility of the proposed effort and provide for the conduct of a requirements analysis study which address... indicate how the results of the requirements analysis study will be incorporated into the proposed system... address requirements analysis, program design, procurement and project management; and, a description of...

  4. Investigating the Application of Needs Analysis on EAP Business Administration Materials

    ERIC Educational Resources Information Center

    Mohammed, Saifalislam Abdalla Hajahmed

    2016-01-01

    This study is conducted to investigate the application of needs analysis in developing EAP materials for business administration students in two Sudanese universities. The subjects are 2 head departments of English language. To collect data, the researcher uses interview and content analysis. The study adopts the descriptive approach. The data of…

  5. Clusters of Occupations Based on Systematically Derived Work Dimensions: An Exploratory Study.

    ERIC Educational Resources Information Center

    Cunningham, J. W.; And Others

    The study explored the feasibility of deriving an educationally relevant occupational cluster structure based on Occupational Analysis Inventory (OAI) work dimensions. A hierarchical cluster analysis was applied to the factor score profiles of 814 occupations on 22 higher-order OAI work dimensions. From that analysis, 73 occupational clusters were…

  6. Content Analysis of a Computer-Based Faculty Activity Repository

    ERIC Educational Resources Information Center

    Baker-Eveleth, Lori; Stone, Robert W.

    2013-01-01

    The research presents an analysis of faculty opinions regarding the introduction of a new computer-based faculty activity repository (FAR) in a university setting. The qualitative study employs content analysis to better understand the phenomenon underlying these faculty opinions and to augment the findings from a quantitative study. A web-based…

  7. Successful Indicators Study (SIS) Methodology Report: Deviant Case Analysis Pilot.

    ERIC Educational Resources Information Center

    Bailey, Jerry; Hafner, Anne

    A deviant case analysis pilot study analyzed California local education agency data to determine the usefulness of regression analysis in predicting change in achievement from 1984 to 1989 and identified outliers or districts that show greater achievement changes than would be expected given changed demographic conditions. This report on the…

  8. Independent component analysis-based source-level hyperlink analysis for two-person neuroscience studies

    NASA Astrophysics Data System (ADS)

    Zhao, Yang; Dai, Rui-Na; Xiao, Xiang; Zhang, Zong; Duan, Lian; Li, Zheng; Zhu, Chao-Zhe

    2017-02-01

    Two-person neuroscience, a perspective in understanding human social cognition and interaction, involves designing immersive social interaction experiments as well as simultaneously recording brain activity of two or more subjects, a process termed "hyperscanning." Using newly developed imaging techniques, the interbrain connectivity or hyperlink of various types of social interaction has been revealed. Functional near-infrared spectroscopy (fNIRS)-hyperscanning provides a more naturalistic environment for experimental paradigms of social interaction and has recently drawn much attention. However, most fNIRS-hyperscanning studies have computed hyperlinks using sensor data directly while ignoring the fact that the sensor-level signals contain confounding noises, which may lead to a loss of sensitivity and specificity in hyperlink analysis. In this study, on the basis of independent component analysis (ICA), a source-level analysis framework is proposed to investigate the hyperlinks in a fNIRS two-person neuroscience study. The performance of five widely used ICA algorithms in extracting sources of interaction was compared in simulative datasets, and increased sensitivity and specificity of hyperlink analysis by our proposed method were demonstrated in both simulative and real two-person experiments.

  9. Limitations in Using Multiple Imputation to Harmonize Individual Participant Data for Meta-Analysis.

    PubMed

    Siddique, Juned; de Chavez, Peter J; Howe, George; Cruden, Gracelyn; Brown, C Hendricks

    2018-02-01

    Individual participant data (IPD) meta-analysis is a meta-analysis in which the individual-level data for each study are obtained and used for synthesis. A common challenge in IPD meta-analysis is when variables of interest are measured differently in different studies. The term harmonization has been coined to describe the procedure of placing variables on the same scale in order to permit pooling of data from a large number of studies. Using data from an IPD meta-analysis of 19 adolescent depression trials, we describe a multiple imputation approach for harmonizing 10 depression measures across the 19 trials by treating those depression measures that were not used in a study as missing data. We then apply diagnostics to address the fit of our imputation model. Even after reducing the scale of our application, we were still unable to produce accurate imputations of the missing values. We describe those features of the data that made it difficult to harmonize the depression measures and provide some guidelines for using multiple imputation for harmonization in IPD meta-analysis.

  10. Scene analysis in the natural environment

    PubMed Central

    Lewicki, Michael S.; Olshausen, Bruno A.; Surlykke, Annemarie; Moss, Cynthia F.

    2014-01-01

    The problem of scene analysis has been studied in a number of different fields over the past decades. These studies have led to important insights into problems of scene analysis, but not all of these insights are widely appreciated, and there remain critical shortcomings in current approaches that hinder further progress. Here we take the view that scene analysis is a universal problem solved by all animals, and that we can gain new insight by studying the problems that animals face in complex natural environments. In particular, the jumping spider, songbird, echolocating bat, and electric fish, all exhibit behaviors that require robust solutions to scene analysis problems encountered in the natural environment. By examining the behaviors of these seemingly disparate animals, we emerge with a framework for studying scene analysis comprising four essential properties: (1) the ability to solve ill-posed problems, (2) the ability to integrate and store information across time and modality, (3) efficient recovery and representation of 3D scene structure, and (4) the use of optimal motor actions for acquiring information to progress toward behavioral goals. PMID:24744740

  11. Modeling zero-modified count and semicontinuous data in health services research part 2: case studies.

    PubMed

    Neelon, Brian; O'Malley, A James; Smith, Valerie A

    2016-11-30

    This article is the second installment of a two-part tutorial on the analysis of zero-modified count and semicontinuous data. Part 1, which appears as a companion piece in this issue of Statistics in Medicine, provides a general background and overview of the topic, with particular emphasis on applications to health services research. Here, we present three case studies highlighting various approaches for the analysis of zero-modified data. The first case study describes methods for analyzing zero-inflated longitudinal count data. Case study 2 considers the use of hurdle models for the analysis of spatiotemporal count data. The third case study discusses an application of marginalized two-part models to the analysis of semicontinuous health expenditure data. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Network analysis of oyster transcriptome revealed a cascade of cellular responses during recovery after heat shock.

    PubMed

    Zhang, Lingling; Hou, Rui; Su, Hailin; Hu, Xiaoli; Wang, Shi; Bao, Zhenmin

    2012-01-01

    Oysters, as a major group of marine bivalves, can tolerate a wide range of natural and anthropogenic stressors including heat stress. Recent studies have shown that oysters pretreated with heat shock can result in induced heat tolerance. A systematic study of cellular recovery from heat shock may provide insights into the mechanism of acquired thermal tolerance. In this study, we performed the first network analysis of oyster transcriptome by reanalyzing microarray data from a previous study. Network analysis revealed a cascade of cellular responses during oyster recovery after heat shock and identified responsive gene modules and key genes. Our study demonstrates the power of network analysis in a non-model organism with poor gene annotations, which can lead to new discoveries that go beyond the focus on individual genes.

  13. Sex estimation from sternal measurements using multidetector computed tomography.

    PubMed

    Ekizoglu, Oguzhan; Hocaoglu, Elif; Inci, Ercan; Bilgili, Mustafa Gokhan; Solmaz, Dilek; Erdil, Irem; Can, Ismail Ozgur

    2014-12-01

    We aimed to show the utility and reliability of sternal morphometric analysis for sex estimation.Sex estimation is a very important step in forensic identification. Skeletal surveys are main methods for sex estimation studies. Morphometric analysis of sternum may provide high accuracy rated data in sex discrimination. In this study, morphometric analysis of sternum was evaluated in 1 mm chest computed tomography scans for sex estimation. Four hundred forty 3 subjects (202 female, 241 male, mean age: 44 ± 8.1 [distribution: 30-60 year old]) were included the study. Manubrium length (ML), mesosternum length (2L), Sternebra 1 (S1W), and Sternebra 3 (S3W) width were measured and also sternal index (SI) was calculated. Differences between genders were evaluated by student t-test. Predictive factors of sex were determined by discrimination analysis and receiver operating characteristic (ROC) analysis. Male sternal measurement values are significantly higher than females (P < 0.001) while SI is significantly low in males (P < 0.001). In discrimination analysis, MSL has high accuracy rate with 80.2% in females and 80.9% in males. MSL also has the best sensitivity (75.9%) and specificity (87.6%) values. Accuracy rates were above 80% in 3 stepwise discrimination analysis for both sexes. Stepwise 1 (ML, MSL, S1W, S3W) has the highest accuracy rate in stepwise discrimination analysis with 86.1% in females and 83.8% in males. Our study showed that morphometric computed tomography analysis of sternum might provide important information for sex estimation.

  14. Genome-wide gene–gene interaction analysis for next-generation sequencing

    PubMed Central

    Zhao, Jinying; Zhu, Yun; Xiong, Momiao

    2016-01-01

    The critical barrier in interaction analysis for next-generation sequencing (NGS) data is that the traditional pairwise interaction analysis that is suitable for common variants is difficult to apply to rare variants because of their prohibitive computational time, large number of tests and low power. The great challenges for successful detection of interactions with NGS data are (1) the demands in the paradigm of changes in interaction analysis; (2) severe multiple testing; and (3) heavy computations. To meet these challenges, we shift the paradigm of interaction analysis between two SNPs to interaction analysis between two genomic regions. In other words, we take a gene as a unit of analysis and use functional data analysis techniques as dimensional reduction tools to develop a novel statistic to collectively test interaction between all possible pairs of SNPs within two genome regions. By intensive simulations, we demonstrate that the functional logistic regression for interaction analysis has the correct type 1 error rates and higher power to detect interaction than the currently used methods. The proposed method was applied to a coronary artery disease dataset from the Wellcome Trust Case Control Consortium (WTCCC) study and the Framingham Heart Study (FHS) dataset, and the early-onset myocardial infarction (EOMI) exome sequence datasets with European origin from the NHLBI's Exome Sequencing Project. We discovered that 6 of 27 pairs of significantly interacted genes in the FHS were replicated in the independent WTCCC study and 24 pairs of significantly interacted genes after applying Bonferroni correction in the EOMI study. PMID:26173972

  15. Meta-analysis with missing study-level sample variance data.

    PubMed

    Chowdhry, Amit K; Dworkin, Robert H; McDermott, Michael P

    2016-07-30

    We consider a study-level meta-analysis with a normally distributed outcome variable and possibly unequal study-level variances, where the object of inference is the difference in means between a treatment and control group. A common complication in such an analysis is missing sample variances for some studies. A frequently used approach is to impute the weighted (by sample size) mean of the observed variances (mean imputation). Another approach is to include only those studies with variances reported (complete case analysis). Both mean imputation and complete case analysis are only valid under the missing-completely-at-random assumption, and even then the inverse variance weights produced are not necessarily optimal. We propose a multiple imputation method employing gamma meta-regression to impute the missing sample variances. Our method takes advantage of study-level covariates that may be used to provide information about the missing data. Through simulation studies, we show that multiple imputation, when the imputation model is correctly specified, is superior to competing methods in terms of confidence interval coverage probability and type I error probability when testing a specified group difference. Finally, we describe a similar approach to handling missing variances in cross-over studies. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  16. What is an adequate sample size? Operationalising data saturation for theory-based interview studies.

    PubMed

    Francis, Jill J; Johnston, Marie; Robertson, Clare; Glidewell, Liz; Entwistle, Vikki; Eccles, Martin P; Grimshaw, Jeremy M

    2010-12-01

    In interview studies, sample size is often justified by interviewing participants until reaching 'data saturation'. However, there is no agreed method of establishing this. We propose principles for deciding saturation in theory-based interview studies (where conceptual categories are pre-established by existing theory). First, specify a minimum sample size for initial analysis (initial analysis sample). Second, specify how many more interviews will be conducted without new ideas emerging (stopping criterion). We demonstrate these principles in two studies, based on the theory of planned behaviour, designed to identify three belief categories (Behavioural, Normative and Control), using an initial analysis sample of 10 and stopping criterion of 3. Study 1 (retrospective analysis of existing data) identified 84 shared beliefs of 14 general medical practitioners about managing patients with sore throat without prescribing antibiotics. The criterion for saturation was achieved for Normative beliefs but not for other beliefs or studywise saturation. In Study 2 (prospective analysis), 17 relatives of people with Paget's disease of the bone reported 44 shared beliefs about taking genetic testing. Studywise data saturation was achieved at interview 17. We propose specification of these principles for reporting data saturation in theory-based interview studies. The principles may be adaptable for other types of studies.

  17. Dietary flavonoid intake and the risk of stroke: a dose-response meta-analysis of prospective cohort studies

    PubMed Central

    Tang, Zhenyu; Li, Min; Zhang, Xiaowei; Hou, Wenshang

    2016-01-01

    Objective To clarify and quantify the potential association between intake of flavonoids and risk of stroke. Design Meta-analysis of prospective cohort studies. Data source Studies published before January 2016 identified through electronic searches using PubMed, Embase and the Cochrane Library. Eligibility criteria for selecting studies Prospective cohort studies with relative risks and 95% CIs for stroke according to intake of flavonoids (assessed as dietary intake). Results The meta-analysis yielded 11 prospective cohort studies involving 356 627 participants and more than 5154 stroke cases. The pooled estimate of the multivariate relative risk of stroke for the highest compared with the lowest dietary flavonoid intake was 0.89 (95% CI 0.82 to 0.97; p=0.006). Dose-response analysis indicated that the summary relative risk of stroke for an increase of 100 mg flavonoids consumed per day was 0.91 (95% CI 0.77 to 1.08) without heterogeneity among studies (I2=0%). Stratifying by follow-up duration, the relative risk of stroke for flavonoid intake was 0.89 (95% CI 0.81 to 0.99) in studies with more than 10 years of follow-up. Conclusions Results from this meta-analysis suggest that higher dietary flavonoid intake may moderately lower the risk of stroke. PMID:27279473

  18. Coupled Aerodynamic and Structural Sensitivity Analysis of a High-Speed Civil Transport

    NASA Technical Reports Server (NTRS)

    Mason, B. H.; Walsh, J. L.

    2001-01-01

    An objective of the High Performance Computing and Communication Program at the NASA Langley Research Center is to demonstrate multidisciplinary shape and sizing optimization of a complete aerospace vehicle configuration by using high-fidelity, finite-element structural analysis and computational fluid dynamics aerodynamic analysis. In a previous study, a multi-disciplinary analysis system for a high-speed civil transport was formulated to integrate a set of existing discipline analysis codes, some of them computationally intensive, This paper is an extension of the previous study, in which the sensitivity analysis for the coupled aerodynamic and structural analysis problem is formulated and implemented. Uncoupled stress sensitivities computed with a constant load vector in a commercial finite element analysis code are compared to coupled aeroelastic sensitivities computed by finite differences. The computational expense of these sensitivity calculation methods is discussed.

  19. Navigation study for low-altitude Earth satellites

    NASA Technical Reports Server (NTRS)

    Pastor, P. R.; Fang, B. T.; Yee, C. P.

    1985-01-01

    This document describes several navigation studies for low-altitude Earth satellites. The use of Global Positioning System Navigation Package data for LANDSAT-5 orbit determination is evaluated. In addition, a navigation analysis for the proposed Tracking and Data Aquisition System is presented. This analysis, based on simulations employing one-way Doppler data, is used to determine the agreement between the Research and Development Goddard Trajectory Determination System and the Sequential Error Analysis Program results. Properties of several geopotential error models are studied and an exploratory study of orbit smoother process noise is presented.

  20. Considerations for the design, analysis and presentation of in vivo studies.

    PubMed

    Ranstam, J; Cook, J A

    2017-03-01

    To describe, explain and give practical suggestions regarding important principles and key methodological challenges in the study design, statistical analysis, and reporting of results from in vivo studies. Pre-specifying endpoints and analysis, recognizing the common underlying assumption of statistically independent observations, performing sample size calculations, and addressing multiplicity issues are important parts of an in vivo study. A clear reporting of results and informative graphical presentations of data are other important parts. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  1. Developing Sampling Frame for Case Study: Challenges and Conditions

    ERIC Educational Resources Information Center

    Ishak, Noriah Mohd; Abu Bakar, Abu Yazid

    2014-01-01

    Due to statistical analysis, the issue of random sampling is pertinent to any quantitative study. Unlike quantitative study, the elimination of inferential statistical analysis, allows qualitative researchers to be more creative in dealing with sampling issue. Since results from qualitative study cannot be generalized to the bigger population,…

  2. The Psychophysiology of Posttraumatic Stress Disorder: A Meta-Analysis

    ERIC Educational Resources Information Center

    Pole, Nnamdi

    2007-01-01

    This meta-analysis of 58 resting baseline studies, 25 startle studies, 17 standardized trauma cue studies, and 22 idiographic trauma cue studies compared adults with and without posttraumatic stress disorder (PTSD) on psychophysiological variables: facial electromyography (EMG), heart rate (HR), skin conductance (SC), and blood pressure.…

  3. DOD/NASA system impact analysis (study 2.1). Volume 2: Study results

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Results of the tug turnaround cost study and the space transportation system (STS) abort modes and effects study are presented for DOD/NASA system impact analysis. Cost estimates are given for tug turnabout; and vehicle description, abort assessment, and abort performance capability are given for the STS.

  4. Understanding virtual water flows: A multiregion input-output case study of Victoria

    NASA Astrophysics Data System (ADS)

    Lenzen, Manfred

    2009-09-01

    This article explains and interprets virtual water flows from the well-established perspective of input-output analysis. Using a case study of the Australian state of Victoria, it demonstrates that input-output analysis can enumerate virtual water flows without systematic and unknown truncation errors, an issue which has been largely absent from the virtual water literature. Whereas a simplified flow analysis from a producer perspective would portray Victoria as a net virtual water importer, enumerating the water embodiments across the full supply chain using input-output analysis shows Victoria as a significant net virtual water exporter. This study has succeeded in informing government policy in Australia, which is an encouraging sign that input-output analysis will be able to contribute much value to other national and international applications.

  5. Shift work, night work, and the risk of prostate cancer: A meta-analysis based on 9 cohort studies.

    PubMed

    Du, Hong-Bing; Bin, Kai-Yun; Liu, Wen-Hong; Yang, Feng-Sheng

    2017-11-01

    Epidemiology studies suggested that shift work or night work may be linked to prostate cancer (PCa); the relationship, however, remains controversy. PubMed, ScienceDirect, and Embase (Ovid) databases were searched before (started from the building of the databases) February 4, 2017 for eligible cohort studies. We pooled the evidence included by a random- or fixed-effect model, according to the heterogeneity. A predefined subgroup analysis was conducted to see the potential discrepancy between groups. Sensitivity analysis was used to test whether our results were stale. Nine cohort studies were eligible for meta-analysis with 2,570,790 male subjects. Our meta-analysis showed that, under the fixed-effect model, the pooled relevant risk (RR) of PCa was 1.05 (95% confidence interval [CI]: 1.00, 1.11; P = .06; I = 24.00%) for men who had ever engaged in night shift work; and under the random-effect model, the pooled RR was 1.08 (0.99, 1.17; P = .08; I = 24.00%). Subgroup analysis showed the RR of PCa among males in western countries was 1.05 (95% CI: 0.99, 1.11; P = .09; I = 0.00%), while among Asian countries it was 2.45 (95% CI: 1.19, 5.04; P = .02; I = 0.00%); and the RR was 1.04 (95% CI: 0.95, 1.14; P = .40; I = 29.20%) for the high-quality group compared with 1.21 (95% CI: 1.03, 1.41; P = .02; I = 0.00%) for the moderate/low-quality group. Sensitivity analysis showed robust results. Based on the current evidence of cohort studies, we found no obvious association between night shift work and PCa. However, our subgroup analysis suggests that night shift work may increase the risk of PCa in Asian men. Some evidence of a small study effect was observed in this meta-analysis.

  6. Diagnostic value of 18F-FDG-PET/CT for the evaluation of solitary pulmonary nodules: a systematic review and meta-analysis.

    PubMed

    Ruilong, Zong; Daohai, Xie; Li, Geng; Xiaohong, Wang; Chunjie, Wang; Lei, Tian

    2017-01-01

    To carry out a meta-analysis on the performance of fluorine-18-fluorodeoxyglucose (F-FDG) PET/computed tomography (PET/CT) for the evaluation of solitary pulmonary nodules. In the meta-analysis, we performed searches of several electronic databases for relevant studies, including Google Scholar, PubMed, Cochrane Library, and several Chinese databases. The quality of all included studies was assessed by Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). Two observers independently extracted data of eligible articles. For the meta-analysis, the total sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratios were pooled. A summary receiver operating characteristic curve was constructed. The I-test was performed to assess the impact of study heterogeneity on the results of the meta-analysis. Meta-regression and subgroup analysis were carried out to investigate the potential covariates that might have considerable impacts on heterogeneity. Overall, 12 studies were included in this meta-analysis, including a total of 1297 patients and 1301 pulmonary nodules. The pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio with corresponding 95% confidence intervals (CIs) were 0.82 (95% CI, 0.76-0.87), 0.81 (95% CI, 0.66-0.90), 4.3 (95% CI, 2.3-7.9), and 0.22 (95% CI, 0.16-0.30), respectively. Significant heterogeneity was observed in sensitivity (I=81.1%) and specificity (I=89.6%). Subgroup analysis showed that the best results for sensitivity (0.90; 95% CI, 0.68-0.86) and accuracy (0.93; 95% CI, 0.90-0.95) were present in a prospective study. The results of our analysis suggest that PET/CT is a useful tool for detecting malignant pulmonary nodules qualitatively. Although current evidence showed moderate accuracy for PET/CT in differentiating malignant from benign solitary pulmonary nodules, further work needs to be carried out to improve its reliability.

  7. Comparison of Estimates between Cohort and Case-Control Studies in Meta-Analyses of Therapeutic Interventions: A Meta-Epidemiological Study.

    PubMed

    Lanza, Amy; Ravaud, Philippe; Riveros, Carolina; Dechartres, Agnes

    2016-01-01

    Observational studies are increasingly being used for assessing therapeutic interventions. Case-control studies are generally considered to have greater risk of bias than cohort studies, but we lack evidence of differences in effect estimates between the 2 study types. We aimed to compare estimates between cohort and case-control studies in meta-analyses of observational studies of therapeutic interventions by using a meta-epidemiological study. We used a random sample of meta-analyses of therapeutic interventions published in 2013 that included both cohort and case-control studies assessing a binary outcome. For each meta-analysis, the ratio of estimates (RE) was calculated by comparing the estimate in case-control studies to that in cohort studies. Then, we used random-effects meta-analysis to estimate a combined RE across meta-analyses. An RE < 1 indicated that case-control studies yielded larger estimates than cohort studies. The final analysis included 23 meta-analyses: 138 cohort and 133 case-control studies. Treatment effect estimates did not significantly differ between case-control and cohort studies (combined RE 0.97 [95% CI 0.86-1.09]). Heterogeneity was low, with between-meta-analysis variance τ2 = 0.0049. Estimates did not differ between case-control and prospective or retrospective cohort studies (RE = 1.05 [95% CI 0.96-1.15] and RE = 0.99 [95% CI, 0.83-1.19], respectively). Sensitivity analysis of studies reporting adjusted estimates also revealed no significant difference (RE = 1.03 [95% CI 0.91-1.16]). Heterogeneity was also low for these analyses. We found no significant difference in treatment effect estimates between case-control and cohort studies assessing therapeutic interventions.

  8. Rare-Variant Association Analysis: Study Designs and Statistical Tests

    PubMed Central

    Lee, Seunggeung; Abecasis, Gonçalo R.; Boehnke, Michael; Lin, Xihong

    2014-01-01

    Despite the extensive discovery of trait- and disease-associated common variants, much of the genetic contribution to complex traits remains unexplained. Rare variants can explain additional disease risk or trait variability. An increasing number of studies are underway to identify trait- and disease-associated rare variants. In this review, we provide an overview of statistical issues in rare-variant association studies with a focus on study designs and statistical tests. We present the design and analysis pipeline of rare-variant studies and review cost-effective sequencing designs and genotyping platforms. We compare various gene- or region-based association tests, including burden tests, variance-component tests, and combined omnibus tests, in terms of their assumptions and performance. Also discussed are the related topics of meta-analysis, population-stratification adjustment, genotype imputation, follow-up studies, and heritability due to rare variants. We provide guidelines for analysis and discuss some of the challenges inherent in these studies and future research directions. PMID:24995866

  9. Strengths weaknesses opportunities and threats of blended learning: students' perceptions.

    PubMed

    Hande, S

    2014-05-01

    Blended learning (BL) in a cell biology course of the premedical program at the Kasturba Medical College International Centre, Manipal, India, commenced in 2006. The program provides training in basic sciences to students, especially from the United States and Canada. The approach to the study was phenomenographic, with a qualitative study design using an open-ended questionnaire, focused interviews and empirical observations. The aim of this study was to identify the strengths, weaknesses, opportunities and threats (SWOT) of BL in a premedical class. It was a cross-sectional study. Ninety six students in a premedical cell biology class participated in the study. SWOT analysis of students' perceptions was conducted manually. Statistical analysis included content analysis of qualitative data to classify data and aligning them into the SWOT analysis matrix. The outcomes of the study revealed student perceptions in terms of SWOT of BL and the potential uses of this strategy. The study provides background for educators and curriculum experts to plan their modules while incorporating a BL approach.

  10. Research Review, 1983

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The Global Modeling and Simulation Branch (GMSB) of the Laboratory for Atmospheric Sciences (GLAS) is engaged in general circulation modeling studies related to global atmospheric and oceanographic research. The research activities discussed are organized into two disciplines: Global Weather/Observing Systems and Climate/Ocean-Air Interactions. The Global Weather activities are grouped in four areas: (1) Analysis and Forecast Studies, (2) Satellite Observing Systems, (3) Analysis and Model Development, (4) Atmospheric Dynamics and Diagnostic Studies. The GLAS Analysis/Forecast/Retrieval System was applied to both FGGE and post FGGE periods. The resulting analyses have already been used in a large number of theoretical studies of atmospheric dynamics, forecast impact studies and development of new or improved algorithms for the utilization of satellite data. Ocean studies have focused on the analysis of long-term global sea surface temperature data, for use in the study of the response of the atmosphere to sea surface temperature anomalies. Climate research has concentrated on the simulation of global cloudiness, and on the sensitivities of the climate to sea surface temperature and ground wetness anomalies.

  11. A study and meta-analysis of lay attributions of cures for overcoming specific psychological problems.

    PubMed

    Furnham, A; Hayward, R

    1997-09-01

    Lay beliefs about the importance of 24 different contributors to overcoming 4 disorders that constitute primarily cognitive deficits were studied. A meta-analysis of previous programmatic studies in the area was performed so that 22 different psychological problems could be compared. In the present study, 107 participants completed a questionnaire indicating how effective 24 factors were in overcoming 4 specific problems: dyslexia, fear of flying, amnesia, and learning difficulties. Factor analysis revealed almost identical clusters (inner control, social consequences, understanding, receiving help, and fate) for each problem. The perceived relevance of those factors differed significantly between problems. Some individual difference factors (sex and religion) were found to predict certain factor attributions for specific disorders. A meta-analysis of the 5 studies in this series yielded a 6-factor structure comparable to those of the individual studies and provided results indicating the benefits and limitations of this kind of investigation. The clinical relevance of studying attributions for cure is considered.

  12. Industrial Water Analysis Program: A Critical Study.

    DTIC Science & Technology

    1983-09-01

    Patterson Air Force Base, Ohio UMAMUION lTATEMNT A APtO.6UPbhtd3WJ 83 11 04 014’ X. .. . INDUSTRIAL WATER ANALYSIS PROGRAM: A CRITICAL STUDY Dennis C...Twhoo-17 (ATC) Wright-FPafewon AFB O 44 3 1S. KEY WORDS (Continue on reverse aide if necessary and identify by block number) Industrial Water Analysis ...Boiler Water Analysis Preservation Procedures Air Force Industrial Water Stabilization Procedures 20. ABSTRACT (Continue on reverse side it necessary and

  13. A Comparative Study of Data Envelopment Analysis and Other Approaches to Efficiency Evaluation and Estimation.

    DTIC Science & Technology

    1982-11-01

    ADA27 91 A COMPARATIVE STJDO DATAENVEOPMENT ANALYSISAND / HER APPROACHES TO A .i)TEXAS UN VAT AUSIN CENTER FOCAS RE CCYR 5 NO BERRETIC STADIES A... COMPARATIVE STUDY OF DATA ENVELOPMENT ANALYSIS AND OTHER APPROACHES TO EFFICIENCY EVALUATION AND ESTIMATIONt by A. Charnes W.W. Cooper H.D. Sherman...School of Business, 1981, entitled "Measurement of Hospital Efficiency: A Comparative Analysis of Data Envelopment Analysis and Other Approaches for

  14. Creating and Manipulating a Domain-Specific Formal Object Base to Support a Domain-Oriented Application Composition System

    DTIC Science & Technology

    1992-12-01

    and add new attributes as needed (11:129). 2.2.3.2 Feature Oriented Domain Analysis In their Feature-Oriented Domain Analysis ( FODA ) study, the...dissertation, The University of Texas at Austin, Austin Texas, 1990. 12. Kang, Kyo C. and others. Feature-Oriented Domain Analysis ( FODA ) Feasibil- ity Study...2-1 2.2.2 Requirements Languages ..................... 2-2 2.2.3 Domain Analysis ............................ 2-3 2.2.4

  15. ROCKETSHIP: a flexible and modular software tool for the planning, processing and analysis of dynamic MRI studies.

    PubMed

    Barnes, Samuel R; Ng, Thomas S C; Santa-Maria, Naomi; Montagne, Axel; Zlokovic, Berislav V; Jacobs, Russell E

    2015-06-16

    Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a promising technique to characterize pathology and evaluate treatment response. However, analysis of DCE-MRI data is complex and benefits from concurrent analysis of multiple kinetic models and parameters. Few software tools are currently available that specifically focuses on DCE-MRI analysis with multiple kinetic models. Here, we developed ROCKETSHIP, an open-source, flexible and modular software for DCE-MRI analysis. ROCKETSHIP incorporates analyses with multiple kinetic models, including data-driven nested model analysis. ROCKETSHIP was implemented using the MATLAB programming language. Robustness of the software to provide reliable fits using multiple kinetic models is demonstrated using simulated data. Simulations also demonstrate the utility of the data-driven nested model analysis. Applicability of ROCKETSHIP for both preclinical and clinical studies is shown using DCE-MRI studies of the human brain and a murine tumor model. A DCE-MRI software suite was implemented and tested using simulations. Its applicability to both preclinical and clinical datasets is shown. ROCKETSHIP was designed to be easily accessible for the beginner, but flexible enough for changes or additions to be made by the advanced user as well. The availability of a flexible analysis tool will aid future studies using DCE-MRI. A public release of ROCKETSHIP is available at https://github.com/petmri/ROCKETSHIP .

  16. Aircraft Conceptual Design and Risk Analysis Using Physics-Based Noise Prediction

    NASA Technical Reports Server (NTRS)

    Olson, Erik D.; Mavris, Dimitri N.

    2006-01-01

    An approach was developed which allows for design studies of commercial aircraft using physics-based noise analysis methods while retaining the ability to perform the rapid trade-off and risk analysis studies needed at the conceptual design stage. A prototype integrated analysis process was created for computing the total aircraft EPNL at the Federal Aviation Regulations Part 36 certification measurement locations using physics-based methods for fan rotor-stator interaction tones and jet mixing noise. The methodology was then used in combination with design of experiments to create response surface equations (RSEs) for the engine and aircraft performance metrics, geometric constraints and take-off and landing noise levels. In addition, Monte Carlo analysis was used to assess the expected variability of the metrics under the influence of uncertainty, and to determine how the variability is affected by the choice of engine cycle. Finally, the RSEs were used to conduct a series of proof-of-concept conceptual-level design studies demonstrating the utility of the approach. The study found that a key advantage to using physics-based analysis during conceptual design lies in the ability to assess the benefits of new technologies as a function of the design to which they are applied. The greatest difficulty in implementing physics-based analysis proved to be the generation of design geometry at a sufficient level of detail for high-fidelity analysis.

  17. Teachers' Professional Development: A Content Analysis about the Tendencies in Studies

    ERIC Educational Resources Information Center

    Yurtseven, Nihal; Bademcioglu, Mehtap

    2016-01-01

    The purpose of this study is to carry out a content analysis about the studies on teachers' professional development and to determine the tendencies in these studies. Within this scope, 60 studies that were registered to Turkish National Thesis Centre and ProQuest database between the years 2005-2015 were examined. Of the 60 studies, 37 of them…

  18. Study design and statistical analysis of data in human population studies with the micronucleus assay.

    PubMed

    Ceppi, Marcello; Gallo, Fabio; Bonassi, Stefano

    2011-01-01

    The most common study design performed in population studies based on the micronucleus (MN) assay, is the cross-sectional study, which is largely performed to evaluate the DNA damaging effects of exposure to genotoxic agents in the workplace, in the environment, as well as from diet or lifestyle factors. Sample size is still a critical issue in the design of MN studies since most recent studies considering gene-environment interaction, often require a sample size of several hundred subjects, which is in many cases difficult to achieve. The control of confounding is another major threat to the validity of causal inference. The most popular confounders considered in population studies using MN are age, gender and smoking habit. Extensive attention is given to the assessment of effect modification, given the increasing inclusion of biomarkers of genetic susceptibility in the study design. Selected issues concerning the statistical treatment of data have been addressed in this mini-review, starting from data description, which is a critical step of statistical analysis, since it allows to detect possible errors in the dataset to be analysed and to check the validity of assumptions required for more complex analyses. Basic issues dealing with statistical analysis of biomarkers are extensively evaluated, including methods to explore the dose-response relationship among two continuous variables and inferential analysis. A critical approach to the use of parametric and non-parametric methods is presented, before addressing the issue of most suitable multivariate models to fit MN data. In the last decade, the quality of statistical analysis of MN data has certainly evolved, although even nowadays only a small number of studies apply the Poisson model, which is the most suitable method for the analysis of MN data.

  19. A Karnaugh map based approach towards systemic reviews and meta-analysis.

    PubMed

    Hassan, Abdul Wahab; Hassan, Ahmad Kamal

    2016-01-01

    Studying meta-analysis and systemic reviews since long had helped us conclude numerous parallel or conflicting studies. Existing studies are presented in tabulated forms which contain appropriate information for specific cases yet it is difficult to visualize. On meta-analysis of data, this can lead to absorption and subsumption errors henceforth having undesirable potential of consecutive misunderstandings in social and operational methodologies. The purpose of this study is to investigate an alternate forum for meta-data presentation that relies on humans' strong pictorial perception capability. Analysis of big-data is assumed to be a complex and daunting task often reserved on the computational powers of machines yet there exist mapping tools which can analyze such data in a hand-handled manner. Data analysis on such scale can benefit from the use of statistical tools like Karnaugh maps where all studies can be put together on a graph based mapping. Such a formulation can lead to more control in observing patterns of research community and analyzing further for uncertainty and reliability metrics. We present a methodological process of converting a well-established study in Health care to its equaling binary representation followed by furnishing values on to a Karnaugh Map. The data used for the studies presented herein is from Burns et al (J Publ Health 34(1):138-148, 2011) consisting of retrospectively collected data sets from various studies on clinical coding data accuracy. Using a customized filtration process, a total of 25 studies were selected for review with no, partial, or complete knowledge of six independent variables thus forming 64 independent cells on a Karnaugh map. The study concluded that this pictorial graphing as expected had helped in simplifying the overview of meta-analysis and systemic reviews.

  20. Night Shift Work and Risk of Depression: Meta-analysis of Observational Studies.

    PubMed

    Lee, Aeyoung; Myung, Seung Kwon; Cho, Jung Jin; Jung, Yu Jin; Yoon, Jong Lull; Kim, Mee Young

    2017-07-01

    This study aimed to assess whether night shift work is associated with the risk of depression by using a meta-analysis of observational studies. We searched PubMed and EMBASE in August, 2016 to locate eligible studies and investigated the association between night shift work and the risk of depression, reporting outcome measures with adjusted odds ratios (ORs) or relative risks (RRs) and 95% confidence intervals (CIs). In the meta-analysis of a total of 11 observational studies with 9 cross-sectional study, 1 longitudinal study, and 1 cohort study, night shift work was significantly associated with an increased risk of depression (OR/RR, 1.43; 95% CI, 1.24-1.64; I² = 78.0%). Also, subgroup meta-analyses by gender, night shift work duration, type of occupation, continent, and type of publication showed that night shift work was consistently associated with the increased risk of depression. The current meta-analysis suggests that night shift work is associated with the increased risk of depression. However, further large prospective cohort studies are needed to confirm this association. © 2017 The Korean Academy of Medical Sciences.

  1. Night Shift Work and Risk of Depression: Meta-analysis of Observational Studies

    PubMed Central

    2017-01-01

    This study aimed to assess whether night shift work is associated with the risk of depression by using a meta-analysis of observational studies. We searched PubMed and EMBASE in August, 2016 to locate eligible studies and investigated the association between night shift work and the risk of depression, reporting outcome measures with adjusted odds ratios (ORs) or relative risks (RRs) and 95% confidence intervals (CIs). In the meta-analysis of a total of 11 observational studies with 9 cross-sectional study, 1 longitudinal study, and 1 cohort study, night shift work was significantly associated with an increased risk of depression (OR/RR, 1.43; 95% CI, 1.24–1.64; I2 = 78.0%). Also, subgroup meta-analyses by gender, night shift work duration, type of occupation, continent, and type of publication showed that night shift work was consistently associated with the increased risk of depression. The current meta-analysis suggests that night shift work is associated with the increased risk of depression. However, further large prospective cohort studies are needed to confirm this association. PMID:28581264

  2. Archaeology: site studies, activation analysis, preservation, and remote sensing. Volume 3. 1978-November 1979 (a bibliography with abstracts). Report for 1978-November 79

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cavagnaro, D.

    1979-12-01

    These citations of federally-funded research are divided into two parts; namely, a chemical analysis of archaeological specimens, and general studies. The chemical analysis section deals primarily with activation analysis. Articles examined include metals, pottery, coins, paintings, soils, glass, and paper from Medieval, Grecian, Egyptian, Mayan, and prehistoric times. The general studies section cites other archaeological research, including results of excavation from the United States. Also covered is work on preservation of artifacts and remote sensing for the site location. (This updated bibliography contains 237 abstracts, 149 of which are new entries to the previous edition.)

  3. Archaeology: site studies, activation analysis, preservation, and remote sensing. December 1979-December 1980 (citations from the NTIS Data Base). Report for December 1970-December 1980

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1981-01-01

    These citations of federally-funded research contains the chemical analysis of archaeological specimens, as well as general studies. The chemical analysis deals primarily with activation analysis. Articles examined include metals, pottery, coins, paintings, soils, glass, and paper from Medieval, Grecian, Egyptian, Mayan, and prehistoric times. The general studies cites other archaeological research, including results of excavation from the United States. Also covered is work on preservation of artifacts and remote sensing for the site location. (This updated bibliography contains 133 citations, all of which are new entries to the previous edition.)

  4. Archaeology: site studies, activation analysis, preservation, and remote sensing. Volume 2. 1977 (a bibliography with abstracts). Report for 1977

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cavagnaro, D.

    1979-12-01

    The cited reports of Federally-funded research are divided into two parts: namely, a chemical analysis of archaeological specimens, and general studies. The chemical analysis section deals primarily with activation analysis. Artifacts examined include metals, pottery, coins, paintings, soils, glass, and paper from Medieval, Grecian, Egyptian, Mayan, and prehistoric times. The general studies section discusses other archaeological research, including results of excavation from the United States. Also covered is work on preservation of artifacts and remote sensing for the site location. (This updated bibliography contains 128 abstracts, none of which are new entries to the previous edition.)

  5. Archaeology: site studies, activation analysis, preservation, and remote sensing. volume 2. 1977-november, 1978 (a bibliography with abstracts). Report for 1977-Nov 78

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cavagnaro, D.M.

    1978-11-01

    These citations of Federally-funded research are divided into two parts; namely, a chemical analysis of archaeological specimens, and general studies. The chemical analysis section deals primarily with activation analysis. Articles examined include metals, pottery, coins, paintings, soils, glass, and paper from Medieval, Grecian, Egyptian, Mayan and prehistoric times. The general studies section cites other archaeological research, including results of excavation from the United States. Also covered is work on preservation of artifacts and remote sensing for the site location. (This updated bibliography contains 209 abstracts, 141 of which are new entries to the previous edition.)

  6. Adaptation and validation of the Spanish version of the Dieting Peer Competitiveness Scale to adolescents of both genders.

    PubMed

    Pamies-Aubalat, Lidia; Quiles-Marcos, Yolanda; Núñez-Núñez, Rosa M

    2013-12-01

    This study examined the Dieting Peer Competitiveness Scale; it is an instrument for evaluating this social comparison in young people. This instrumental study has two aims: The objective of the first aim was to present preliminary psychometric data from the Spanish version of the Dieting Peer Competitiveness Scale, including statistical item analysis, research about this instrument's internal structure, and a reliability analysis, from a sample of 1067 secondary school adolescents. The second objective of the study corresponds to confirmatory factor analysis of the scale's internal structure, as well as analysis for evidence of validity from a sample of 1075 adolescents.

  7. Ataxia Telangiectasia–Mutated Gene Polymorphisms and Acute Normal Tissue Injuries in Cancer Patients After Radiation Therapy: A Systematic Review and Meta-analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dong, Lihua; Cui, Jingkun; Tang, Fengjiao

    Purpose: Studies of the association between ataxia telangiectasia–mutated (ATM) gene polymorphisms and acute radiation injuries are often small in sample size, and the results are inconsistent. We conducted the first meta-analysis to provide a systematic review of published findings. Methods and Materials: Publications were identified by searching PubMed up to April 25, 2014. Primary meta-analysis was performed for all acute radiation injuries, and subgroup meta-analyses were based on clinical endpoint. The influence of sample size and radiation injury incidence on genetic effects was estimated in sensitivity analyses. Power calculations were also conducted. Results: The meta-analysis was conducted on the ATMmore » polymorphism rs1801516, including 5 studies with 1588 participants. For all studies, the cut-off for differentiating cases from controls was grade 2 acute radiation injuries. The primary meta-analysis showed a significant association with overall acute radiation injuries (allelic model: odds ratio = 1.33, 95% confidence interval: 1.04-1.71). Subgroup analyses detected an association between the rs1801516 polymorphism and a significant increase in urinary and lower gastrointestinal injuries and an increase in skin injury that was not statistically significant. There was no between-study heterogeneity in any meta-analyses. In the sensitivity analyses, small studies did not show larger effects than large studies. In addition, studies with high incidence of acute radiation injuries showed larger effects than studies with low incidence. Power calculations revealed that the statistical power of the primary meta-analysis was borderline, whereas there was adequate power for the subgroup analysis of studies with high incidence of acute radiation injuries. Conclusions: Our meta-analysis showed a consistency of the results from the overall and subgroup analyses. We also showed that the genetic effect of the rs1801516 polymorphism on acute radiation injuries was dependent on the incidence of the injury. These support the evidence of an association between the rs1801516 polymorphism and acute radiation injuries, encouraging further research of this topic.« less

  8. Association between the rs1143634 polymorphism in interleukin-1B and chronic periodontitis: Results from a meta-analysis composed by 54 case/control studies.

    PubMed

    da Silva, Felipe Rodolfo Pereira; Vasconcelos, Any Carolina Cardoso Guimarães; de Carvalho França, Luiz Felipe; Di Lenardo, David; Nascimento, Hélio Mateus Silva; Vasconcelos, Daniel Fernando Pereira

    2018-08-20

    Several factors are involved in the periodontitis with host response through cytokines and as well as with influence of polymorphisms in cytokine genes, however the results remained contradictory. This study aimed at evaluating the rs1143634 polymorphism in interleukin-1B gene, a cytokine gene, and the risk of chronic periodontitis with conducting a meta-analysis focusing in ethnicity. A review in literature was performed in several databases to studies published before June 2017. Data extraction was performed by two calibrated investigators and the calculations of the meta-analysis were obtained through Review Manager version 5.2 statistical software with Odds Ratio (OR) calculation and Funnel plot (P < 0.05) to heterogeneity and the Comprehensive Meta-analysis version 3.3.070 to assessment publication bias by Egger's and Begg's tests. In overall, 54 case/control studies composed the meta-analysis. T allele was significantly associated with patients case (OR = 1.35, 95% CI: 1.24, 1.48, P < 0.00001) in the overall analysis. The stratified evaluation showed the rs1143634 polymorphism had significant association with disease in Caucasian, Asian and mixed population was excepted in African ethnicity (P > 0.05). No publication bias was found in allelic evaluation. This meta-analysis in 9376 participants with 54 case/control studies revealed the rs1143634 polymorphism was associated with elevated risk of chronic periodontitis in overall analysis as well as Caucasian and Asian ethnicities and Mixed population. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Assessment of environmental impacts part one. Intervention analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hipel, Keith William; Lettenmaier, Dennis P.; McLeod, A. Ian

    The use of intervention analysis as a statistical method of gauging the effects of environmental changes is discussed. The Box-Jenkins model, serves as the basis for the intervention analysis methodology. Environmental studies of the Aswan Dam, the South Saskatchewan River, and a forest fire near the Pipers Hole River, Canada, are included as case studies in which intervention analysis was employed. Methods of data collection for intervention analysis are found to have a significant impact on model reliability; effective data collection processes for the Box-Jenkins model are provided. (15 graphs, 27 references, 2 tables)

  10. Drivers of wetland conversion: a global meta-analysis.

    PubMed

    van Asselen, Sanneke; Verburg, Peter H; Vermaat, Jan E; Janse, Jan H

    2013-01-01

    Meta-analysis of case studies has become an important tool for synthesizing case study findings in land change. Meta-analyses of deforestation, urbanization, desertification and change in shifting cultivation systems have been published. This present study adds to this literature, with an analysis of the proximate causes and underlying forces of wetland conversion at a global scale using two complementary approaches of systematic review. Firstly, a meta-analysis of 105 case-study papers describing wetland conversion was performed, showing that different combinations of multiple-factor proximate causes, and underlying forces, drive wetland conversion. Agricultural development has been the main proximate cause of wetland conversion, and economic growth and population density are the most frequently identified underlying forces. Secondly, to add a more quantitative component to the study, a logistic meta-regression analysis was performed to estimate the likelihood of wetland conversion worldwide, using globally-consistent biophysical and socioeconomic location factor maps. Significant factors explaining wetland conversion, in order of importance, are market influence, total wetland area (lower conversion probability), mean annual temperature and cropland or built-up area. The regression analyses results support the outcomes of the meta-analysis of the processes of conversion mentioned in the individual case studies. In other meta-analyses of land change, similar factors (e.g., agricultural development, population growth, market/economic factors) are also identified as important causes of various types of land change (e.g., deforestation, desertification). Meta-analysis helps to identify commonalities across the various local case studies and identify which variables may lead to individual cases to behave differently. The meta-regression provides maps indicating the likelihood of wetland conversion worldwide based on the location factors that have determined historic conversions.

  11. Meta-analysis of thirty-two case-control and two ecological radon studies of lung cancer.

    PubMed

    Dobrzynski, Ludwik; Fornalski, Krzysztof W; Reszczynska, Joanna

    2018-03-01

    A re-analysis has been carried out of thirty-two case-control and two ecological studies concerning the influence of radon, a radioactive gas, on the risk of lung cancer. Three mathematically simplest dose-response relationships (models) were tested: constant (zero health effect), linear, and parabolic (linear-quadratic). Health effect end-points reported in the analysed studies are odds ratios or relative risk ratios, related either to morbidity or mortality. In our preliminary analysis, we show that the results of dose-response fitting are qualitatively (within uncertainties, given as error bars) the same, whichever of these health effect end-points are applied. Therefore, we deemed it reasonable to aggregate all response data into the so-called Relative Health Factor and jointly analysed such mixed data, to obtain better statistical power. In the second part of our analysis, robust Bayesian and classical methods of analysis were applied to this combined dataset. In this part of our analysis, we selected different subranges of radon concentrations. In view of substantial differences between the methodology used by the authors of case-control and ecological studies, the mathematical relationships (models) were applied mainly to the thirty-two case-control studies. The degree to which the two ecological studies, analysed separately, affect the overall results when combined with the thirty-two case-control studies, has also been evaluated. In all, as a result of our meta-analysis of the combined cohort, we conclude that the analysed data concerning radon concentrations below ~1000 Bq/m3 (~20 mSv/year of effective dose to the whole body) do not support the thesis that radon may be a cause of any statistically significant increase in lung cancer incidence.

  12. Physical activity is associated with reduced risk of esophageal cancer, particularly esophageal adenocarcinoma: a systematic review and meta-analysis

    PubMed Central

    2014-01-01

    Background Physical activity has been inversely associated with risk of several cancers. We performed a systematic review and meta-analysis to evaluate the association between physical activity and risk of esophageal cancer (esophageal adenocarcinoma [EAC] and/or esophageal squamous cell carcinoma [ESCC]). Methods We conducted a comprehensive search of bibliographic databases and conference proceedings from inception through February 2013 for observational studies that examined associations between recreational and/or occupational physical activity and esophageal cancer risk. Summary adjusted odds ratio (OR) estimates with 95% confidence intervals (CI) were estimated using the random-effects model. Results The analysis included 9 studies (4 cohort, 5 case–control) reporting 1,871 cases of esophageal cancer among 1,381,844 patients. Meta-analysis demonstrated that the risk of esophageal cancer was 29% lower among the most physically active compared to the least physically active subjects (OR, 0.71; 95% CI, 0.57-0.89), with moderate heterogeneity (I2 = 47%). On histology-specific analysis, physical activity was associated with a 32% decreased risk of EAC (4 studies, 503 cases of EAC; OR, 0.68; 95% CI, 0.55-0.85) with minimal heterogeneity (I2 = 0%). There were only 3 studies reporting the association between physical activity and risk of ESCC with conflicting results, and the meta-analysis demonstrated a null association (OR, 1.10; 95% CI, 0.21-5.64). The results were consistent across study design, geographic location and study quality, with a non-significant trend towards a dose–response relationship. Conclusions Meta-analysis of published observational studies indicates that physical activity may be associated with reduced risk of esophageal adenocarcinoma. Lifestyle interventions focusing on increasing physical activity may decrease the global burden of EAC. PMID:24886123

  13. Drivers of Wetland Conversion: a Global Meta-Analysis

    PubMed Central

    van Asselen, Sanneke; Verburg, Peter H.; Vermaat, Jan E.; Janse, Jan H.

    2013-01-01

    Meta-analysis of case studies has become an important tool for synthesizing case study findings in land change. Meta-analyses of deforestation, urbanization, desertification and change in shifting cultivation systems have been published. This present study adds to this literature, with an analysis of the proximate causes and underlying forces of wetland conversion at a global scale using two complementary approaches of systematic review. Firstly, a meta-analysis of 105 case-study papers describing wetland conversion was performed, showing that different combinations of multiple-factor proximate causes, and underlying forces, drive wetland conversion. Agricultural development has been the main proximate cause of wetland conversion, and economic growth and population density are the most frequently identified underlying forces. Secondly, to add a more quantitative component to the study, a logistic meta-regression analysis was performed to estimate the likelihood of wetland conversion worldwide, using globally-consistent biophysical and socioeconomic location factor maps. Significant factors explaining wetland conversion, in order of importance, are market influence, total wetland area (lower conversion probability), mean annual temperature and cropland or built-up area. The regression analyses results support the outcomes of the meta-analysis of the processes of conversion mentioned in the individual case studies. In other meta-analyses of land change, similar factors (e.g., agricultural development, population growth, market/economic factors) are also identified as important causes of various types of land change (e.g., deforestation, desertification). Meta-analysis helps to identify commonalities across the various local case studies and identify which variables may lead to individual cases to behave differently. The meta-regression provides maps indicating the likelihood of wetland conversion worldwide based on the location factors that have determined historic conversions. PMID:24282580

  14. Consumption of vegetables and fruit and the risk of inflammatory bowel disease: a meta-analysis.

    PubMed

    Li, Fang; Liu, Xiaoqin; Wang, Weijing; Zhang, Dongfeng

    2015-06-01

    To date, associations between consumption of vegetables and fruit and the risk of inflammatory bowel disease have been a controversial subject. Therefore, we carried out a meta-analysis to evaluate the associations. A comprehensive search was performed in PubMed, Embase, Web of Science, and the China National Knowledge Infrastructure to identify all relevant studies. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) from random-effects or fixed-effects models were calculated. Publication bias was estimated using Egger's test and the funnel plot. A total of 14 case-control studies were included in this meta-analysis. On the basis of the highest versus the lowest analysis, consumption of vegetables was associated inversely with the risk of ulcerative colitis (UC) (OR=0.71, 95% CI 0.58-0.88, n=9 studies), but not with Crohn's disease (CD) (OR=0.66, 95% CI 0.40-1.09, n=8 studies). Higher consumption of fruit was associated inversely with the risk of UC (OR=0.69, 95% CI 0.49-0.96, n=8 studies) and CD (OR=0.57, 95% CI 0.44-0.74, n=10 studies). For intake of vegetables and the risk of CD, subgroup analysis showed a significant association for studies carried out in Europe (OR=0.36, 95% CI 0.23-0.57), but not in Asia (OR=1.00, 95% CI 0.50-2.03). No significant publication bias was found for the analysis of intake of vegetables and the risk of UC, intake of fruit and the risk of UC, and intake of vegetables and the risk of CD. This meta-analysis indicates that consumption of vegetables and fruit might be associated inversely with the risk of UC and CD, and the results need to be further confirmed.

  15. Writing for Learning in Science: A Secondary Analysis of Six Studies

    ERIC Educational Resources Information Center

    Gunel, Murat; Hand, Brian; Prain, Vaughan

    2007-01-01

    This study is a secondary analysis of six previous studies that formed part of an ongoing research program focused on examining the benefits of using writing-to-learn strategies within science classrooms. The study is an attempt to make broader generalizations than those based on individual studies, given limitations related to sample sizes,…

  16. A Content Analysis Concerning the Studies on Challenges Faced by Novice Teachers

    ERIC Educational Resources Information Center

    Kozikoglu, Ishak

    2017-01-01

    The purpose of this research is to analyze the studies concerning challenges faced by novice teachers in terms of various aspects and compare challenges according to location of the studies conducted in Turkey and abroad. A total of 30 research studies were included in detailed analysis. This is a descriptive study based on qualitative research…

  17. Content Analysis of Curriculum-Related Studies in Turkey between 2000 and 2014

    ERIC Educational Resources Information Center

    Aksan, Elif; Baki, Adnan

    2017-01-01

    This study aims to carry out a content analysis determining the general framework of studies related to curriculum. For this purpose, 154 curriculum-related studies carried out in Turkey between 2000 and 2014 were examined in terms of year, sample, method, data collection technique, purpose, and result. The most studies related to curriculum were…

  18. USAF (United States Air Force) Stability and Control DATCOM (Data Compendium)

    DTIC Science & Technology

    1978-04-01

    regression analysis involves the study of a group of variables to determine their effect on a given parameter. Because of the empirical nature of this...regression analysis of mathematical statistics. In general, a regression analysis involves the study of a group of variables to determine their effect on a...Excperiment, OSR TN 58-114, MIT Fluid Dynamics Research Group Rapt. 57-5, 1957. (U) 90. Kennet, H., and Ashley, H.: Review of Unsteady Aerodynamic Studies in

  19. A Preliminary Study: USMC Tactical Communications Technical Control Needs for the Landing Force Integrated Communications System.

    DTIC Science & Technology

    1985-09-01

    BSTRACT This study uses a systems analysis approach to determine the communications technical control needs of the Fleet Marine Force as the transition...subsequent analysis and decision. In the acquisi- tion of military systems, it is typical to find these assumptions used to construct various measures of...relatively free from the typical underlying estimates used in cost and operational effective- ness analysis (COEA) type studies which are designed to compare

  20. Prognostic value of pretreatment albumin/globulin ratio in digestive system cancers: A meta-analysis.

    PubMed

    Guo, Hui-Wen; Yuan, Tang-Zhan; Chen, Jia-Xi; Zheng, Yang

    2018-01-01

    The albumin/globulin ratio (AGR) has been widely reported to be a potential predictor of prognosis in digestive system cancers (DSCs), but convincing conclusions have not been made. Therefore, herein, we performed a meta-analysis of relevant studies regarding this topic to evaluate the prognostic value of AGR in patients with DSCs. Three databases, including PubMed, EMBase, and Web of science, were searched comprehensively for eligible studies through September 8, 2017. The outcomes of interest included overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS). In our meta-analysis, pooled analysis of 13 studies with 9269 patients showed that a low AGR was significantly correlated with poor OS (HR = 1.94; 95% CI: 1.57-2.38; P <0.001). Five studies with 6538 participants involved DFS, and our pooled analysis of these studies also demonstrated that there was a significant association of a low AGR with worse DFS (HR = 1.49; 95% CI: 1.10 to 2.00; P < 0.001). In addition, only 2 studies referred to CSS, and we also detected a significant relationship between a low AGR and worse CSS from the results of our meta-analysis. In summary, a low pretreatment AGR was related to unfavorable survival in human digestive system cancers. A low pretreatment AGR may be a useful predictive prognostic biomarker in human digestive system cancers.

  1. The use of paleo-imaging and microbiological testing in the analysis of antique cultural material: multislice tomography, and microbial analysis of the Trogir Cathedral cope hood depicting St. Martin and a beggar.

    PubMed

    Cavka, Mislav; Petaros, Anja; Kavur, Lovro; Skrlin, Jasenka; Mlinaric Missoni, Emilija; Jankovic, Ivor; Brkljacic, Boris

    2013-01-01

    Paleoradiology is the study of biological and other materials from archeological settings through the use of various medical imaging techniques. Although it is most often used in the scientific study of ancient human remains, it can also be used to study metals, ceramics, paper, and clothes. The aim of this study was to test two paleoimaging techniques (MSCT and mammography) in the analysis of an important Croatian liturgical vestment: the hood of a bishop's cope from St. Lawrence's Treasury in Trogir depicting St. Martin and a beggar. To ensure a safe environment for scientists participating in the analysis, a preliminary microbiological analysis was performed, which contributed to the database of microbiological flora found on Croatian archeological remains and relics studied to date. Due to a great amount of metal filaments, the paleoradiological analysis did not produce satisfactory results. However, a digitally enhanced image clearly showed fine metal embroidery of the hood that was not so easily perceived by naked eye. This article argues in favor of expanding paleoradiological studies on materials other than human remains and also of publishing unsatisfactory results, as important lessons for future development of techniques and methods to analyze ancient remains and seek answers about human historical and cultural heritage.

  2. Vitamin B6 Intake and the Risk of Colorectal Cancer: A Meta-Analysis of Prospective Cohort Studies.

    PubMed

    Jia, Kai; Wang, Rong; Tian, Jingfeng

    2017-07-01

    We performed this meta-analysis to estimate the association between vitamin B 6 intake and colorectal cancer risk. Prospective cohort studies on vitamin B 6 intake and colorectal cancer risk were identified by searching databases from the period of 1960 to 2016. Results from individual studies were synthetically combined using Stata 13.0 software. A total of 10 prospective cohort studies including 13 data sets were included in our meta-analysis, containing 7,817 cases and 784,550 subjects. The combined relative risks (RR) of colorectal cancer for the highest vitamin B 6 intake compared with the lowest vitamin B 6 intake was 0.88 [95% confidence intervals (CIs): 0.77-1.02]. Dose-response meta-analysis based on five eligible studies showed that for each additional 3 and 5 mg of vitamin B 6 intake, the risk would decrease by 11% (RR: 0.89, 95%CI: 0.81-0.98) and 17% (RR: 0.83, 95%CI: 0.71-0.97), respectively. Little evidence of publication bias was found. This meta-analysis provides evidence of a nonsignificant decrease in colorectal cancer risk associated with the high level of vitamin B 6 intake, but the risk in dose-response analysis is significant. However, the latter finding is based on a limited number of studies, which should be interpreted with caution.

  3. Family history of diabetes and the risk of gestational diabetes mellitus in Iran: A systematic review and meta-analysis.

    PubMed

    Moosazadeh, Mahmood; Asemi, Zatollah; Lankarani, Kamran B; Tabrizi, Reza; Maharlouei, Najmeh; Naghibzadeh-Tahami, Ahmad; Yousefzadeh, Gholamreza; Sadeghi, Reza; Khatibi, Seyed Reza; Afshari, Mahdi; Khodadost, Mahmoud; Akbari, Maryam

    2017-11-01

    Gestational diabetes is the most prevalent metabolic disorder being firstly diagnosed during pregnancy. The relationship between the family history of diabetes and the gestational diabetes mellitus (GDM) has been investigated in several primary studies with a number of contradictions in the results. Hence, the purpose of the present study is to determine the relationship between the GDM and the family history of diabetes using the meta-analysis method. All published papers in main national and international databases were systematically searched with some specific keywords to find the related studies between 2000 and 2016. We calculated the odds ratio (OR) with 95% confidence interval (CI) in analysis for each study using a random-effect and Mantel-Haenzel method. We also determined heterogeneity among these 33 articles and their publication bias. We entered 33 relevant studies of 2516 articles into the meta-analysis process including 2697 women with family history of diabetes mellitus as well as 29134 women without. Of them, 954 and 4372 subjects developed GDM respectively. Combining the results of the primary studies using the meta-analysis method, the overall odds ratio of family history for developing GDM was estimated as of 3.46 (95% CI: 2.80-4.27). This meta-analysis study revealed that the family history of diabetes is an important risk factor for the gestational diabetes mellitus. Copyright © 2016 Diabetes India. Published by Elsevier Ltd. All rights reserved.

  4. Statistical methodology for estimating the mean difference in a meta-analysis without study-specific variance information.

    PubMed

    Sangnawakij, Patarawan; Böhning, Dankmar; Adams, Stephen; Stanton, Michael; Holling, Heinz

    2017-04-30

    Statistical inference for analyzing the results from several independent studies on the same quantity of interest has been investigated frequently in recent decades. Typically, any meta-analytic inference requires that the quantity of interest is available from each study together with an estimate of its variability. The current work is motivated by a meta-analysis on comparing two treatments (thoracoscopic and open) of congenital lung malformations in young children. Quantities of interest include continuous end-points such as length of operation or number of chest tube days. As studies only report mean values (and no standard errors or confidence intervals), the question arises how meta-analytic inference can be developed. We suggest two methods to estimate study-specific variances in such a meta-analysis, where only sample means and sample sizes are available in the treatment arms. A general likelihood ratio test is derived for testing equality of variances in two groups. By means of simulation studies, the bias and estimated standard error of the overall mean difference from both methodologies are evaluated and compared with two existing approaches: complete study analysis only and partial variance information. The performance of the test is evaluated in terms of type I error. Additionally, we illustrate these methods in the meta-analysis on comparing thoracoscopic and open surgery for congenital lung malformations and in a meta-analysis on the change in renal function after kidney donation. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Using meta-analysis to inform the design of subsequent studies of diagnostic test accuracy.

    PubMed

    Hinchliffe, Sally R; Crowther, Michael J; Phillips, Robert S; Sutton, Alex J

    2013-06-01

    An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial evidence to underpin reliable clinical decision-making. Very few investigators consider any sample size calculations when designing a new diagnostic accuracy study. However, it is important to consider the number of subjects in a new study in order to achieve a precise measure of accuracy. Sutton et al. have suggested previously that when designing a new therapeutic trial, it could be more beneficial to consider the power of the updated meta-analysis including the new trial rather than of the new trial itself. The methodology involves simulating new studies for a range of sample sizes and estimating the power of the updated meta-analysis with each new study added. Plotting the power values against the range of sample sizes allows the clinician to make an informed decision about the sample size of a new trial. This paper extends this approach from the trial setting and applies it to diagnostic accuracy studies. Several meta-analytic models are considered including bivariate random effects meta-analysis that models the correlation between sensitivity and specificity. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.

  6. Analytical characterization of recombinant hCG and comparative studies with reference product.

    PubMed

    Thennati, Rajamannar; Singh, Sanjay Kumar; Nage, Nitin; Patel, Yena; Bose, Sandip Kumar; Burade, Vinod; Ranbhor, Ranjit Sudhakar

    2018-01-01

    Regulatory agencies recommend a stepwise approach for demonstrating biosimilarity between a proposed biosimilar and reference biological product emphasizing for functional and structural characterization to trace if there is any difference which may impact safety and efficacy. We studied the comparative structural and biological attributes of recombinant human chorionic gonadotropin (rhCG), SB005, with reference product, Ovidrel ® and Ovitrelle ® . Recombiant hCG was approved in 2000 by the US Food and Drug Administration for the induction of final follicular maturation, early luteinization in infertile women as part of assisted reproductive technology program. It is also indicated for the induction of ovulation and pregnancy in ovulatory infertile patients whose cause of infertility is not due to ovarian failure. Primary structure was studied by intact mass analysis, peptide fingerprinting, peptide mass fingerprinting and sequence coverage analysis. Higher order structure was studied by circular dichroism, ultraviolet-visible spectroscopy, fluorescence spectroscopy, and disulfide bridge analysis. Different isoforms of reference product and SB005 were identified using capillary isoelectric focusing and capillary zone electrophoresis. Glycosylation was studied by N-glycan mapping using LC-ESI-MS, point of glycosylation, released glycan analysis using ultra performance liquid chromatography and sialic acid analysis. Product related impurities such as oligomer content analysis and oxidized impurities were studied using size exclusion chromatography and reverse phase high performance liquid chromatography, respectively. Biological activity in term of potency of reference product and SB005 was studied by in vivo analysis. In this study we have compared analytical similarity of recombinant rhCG (SB005) produced at Sun Pharmaceuticals with the reference product with respect to its primary, higher order structure, isoforms, charge variants, glycosylation, sialyation pattern, pharmacodynamic and in vivo efficacy. Our studies show that the in house produced rhCG has a high degree of structural and functional similarity with the reference product available in the market.

  7. Analytical characterization of recombinant hCG and comparative studies with reference product

    PubMed Central

    Thennati, Rajamannar; Singh, Sanjay Kumar; Nage, Nitin; Patel, Yena; Bose, Sandip Kumar; Burade, Vinod

    2018-01-01

    Introduction Regulatory agencies recommend a stepwise approach for demonstrating biosimilarity between a proposed biosimilar and reference biological product emphasizing for functional and structural characterization to trace if there is any difference which may impact safety and efficacy. We studied the comparative structural and biological attributes of recombinant human chorionic gonadotropin (rhCG), SB005, with reference product, Ovidrel® and Ovitrelle®. Recombiant hCG was approved in 2000 by the US Food and Drug Administration for the induction of final follicular maturation, early luteinization in infertile women as part of assisted reproductive technology program. It is also indicated for the induction of ovulation and pregnancy in ovulatory infertile patients whose cause of infertility is not due to ovarian failure. Materials and methods Primary structure was studied by intact mass analysis, peptide fingerprinting, peptide mass fingerprinting and sequence coverage analysis. Higher order structure was studied by circular dichroism, ultraviolet-visible spectroscopy, fluorescence spectroscopy, and disulfide bridge analysis. Different isoforms of reference product and SB005 were identified using capillary isoelectric focusing and capillary zone electrophoresis. Glycosylation was studied by N-glycan mapping using LC-ESI-MS, point of glycosylation, released glycan analysis using ultra performance liquid chromatography and sialic acid analysis. Product related impurities such as oligomer content analysis and oxidized impurities were studied using size exclusion chromatography and reverse phase high performance liquid chromatography, respectively. Biological activity in term of potency of reference product and SB005 was studied by in vivo analysis. Results and Conclusion In this study we have compared analytical similarity of recombinant rhCG (SB005) produced at Sun Pharmaceuticals with the reference product with respect to its primary, higher order structure, isoforms, charge variants, glycosylation, sialyation pattern, pharmacodynamic and in vivo efficacy. Our studies show that the in house produced rhCG has a high degree of structural and functional similarity with the reference product available in the market. PMID:29430170

  8. Advanced Connectivity Analysis (ACA): a Large Scale Functional Connectivity Data Mining Environment.

    PubMed

    Chen, Rong; Nixon, Erika; Herskovits, Edward

    2016-04-01

    Using resting-state functional magnetic resonance imaging (rs-fMRI) to study functional connectivity is of great importance to understand normal development and function as well as a host of neurological and psychiatric disorders. Seed-based analysis is one of the most widely used rs-fMRI analysis methods. Here we describe a freely available large scale functional connectivity data mining software package called Advanced Connectivity Analysis (ACA). ACA enables large-scale seed-based analysis and brain-behavior analysis. It can seamlessly examine a large number of seed regions with minimal user input. ACA has a brain-behavior analysis component to delineate associations among imaging biomarkers and one or more behavioral variables. We demonstrate applications of ACA to rs-fMRI data sets from a study of autism.

  9. Survival rates and prognostic predictors of high grade brain stem gliomas in childhood: a systematic review and meta-analysis.

    PubMed

    Hassan, Hadeel; Pinches, Anne; Picton, Susan V; Phillips, Robert S

    2017-10-01

    Diagnosis of a pediatric high grade brain stem glioma is devastating with dismal outcomes. This systematic review and meta-analysis was undertaken to determine the survival rates and assess potential prognostic factors including selected interventions. Studies included involved pediatric participants with high grade brain stem gliomas diagnosed by magnetic resonance imaging or biopsy reporting overall survival rates. Meta-analysis was undertaken using a binomial random effects model. Sixty-five studies (2336 participants) were included. Meta-analysis showed 1 year overall survival (OS) of 41% (95% confidence interval (CI) 38-44%, I-sq 52%, 2083 participants), 2 year OS of 15.3% (95% confidence interval 12-20%, I-sq 73.1%, 1329 participants) and 3 year OS of 7.3% (95% confidence interval 5.2-10%, I-sq 26%, 584 participants). Meta-analyses of median overall survival results was not possible due to the lack of reported measures of variance. Subgroup analysis comparing date of study, classification of tumor, use of temozolomide, non-standard interventions or phase 1/2 versus other studies demonstrated no difference in survival outcomes. There was insufficient data to undertake subgroup meta-analysis of patient age, duration of symptoms, K27M histone mutations and AVCR1 mutations. Survival outcomes of high grade brain stem gliomas have remained very poor, and do not clearly vary according to classification, phase of study or use of different therapeutic interventions. Future studies should harmonize outcome and prognostic variable reporting to enable accurate meta-analysis and better exploration of prognosis.

  10. Processed red meat intake and risk of COPD: A systematic review and dose-response meta-analysis of prospective cohort studies.

    PubMed

    Salari-Moghaddam, Asma; Milajerdi, Alireza; Larijani, Bagher; Esmaillzadeh, Ahmad

    2018-06-01

    No earlier study has summarized findings from previous publications on processed red meat intake and risk of Chronic Obstructive Pulmonary Disease (COPD). This systematic review and meta-analysis was conducted to examine the association between processed red meat intake and COPD risk. We searched in PubMed/Medline, ISI Web of Knowledge, Scopus, EMBASE and Google Scholar up to April 2018 to identify relevant studies. Prospective cohort studies that considered processed red meat as the exposure variable and COPD as the main outcome variable or as one of the outcomes were included in the systematic review. Publications in which hazard ratios (HRs) were reported as effect size were included in the meta-analysis. Finally, five cohort studies were considered in this systematic review and meta-analysis. In total, 289,952 participants, including 8338 subjects with COPD, aged ≥27 years were included in the meta-analysis. These studies were from Sweden and the US. Linear dose response meta-analysis revealed that each 50 gr/week increase in processed red meat intake was associated with 8% higher risk of COPD (HR: 1.08; 95% CI: 1.03, 1.13). There was an evidence of non-linear association between processed red meat intake and risk of COPD (P < 0.001). In this systematic review and meta-analysis, we found a significant positive association between processed red meat intake and risk of COPD. CRD42017077971. Copyright © 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  11. Meta-analysis of lung cancer in asphalt roofing and paving workers with external adjustment for confounding by coal tar

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fayerweather, W.E.

    2007-07-01

    The study's objectives were to update Partanen's and Boffetta's 1994 meta-analysis of lung cancer among roofing and paving asphalt workers and explore the role of coal tar in explaining the statistical heterogeneity among these studies. Information retrieval strategies and eligibility criteria were defined for identifying the epidemiologic studies to be included in the analysis. The relative risk ratio (RR) for lung cancer was selected as the effect measure of interest. Coal tar bias factors were developed and used to externally adjust each eligible study's published RR for confounding by coal tar. The meta-Relative Risk (meta-RR) and its variance were estimatedmore » by general variance-based methods. Heterogeneity of the RRs was assessed by heterogeneity chi-square and I{sup 2} tests. The results from this update were similar to those in Partanen's and Boffetta's original meta-analysis. Although the meta-RRs for the roofers and the pavers were no longer statistically significantly different from one another, significant heterogeneity remained within each of the coal tar-adjusted sectors. Meta-analysis of non-experimental epidemiologic studies is subject to significant uncertainties as is externally correcting studies for confounding. Given these uncertainties, the specific quantitative estimates in this (or any similar) analysis must be viewed with caution. Nevertheless, this analysis provides support for the hypothesis proposed by several major reviewers that confounding by coal tar-related PAH exposures may explain most or all of the lung cancer risks found in the epidemiologic literature on asphalt roofing and paving workers.« less

  12. A systematic review and meta-analysis of the circulatory, erythrocellular and CSF selenium levels in Alzheimer's disease: A metal meta-analysis (AMMA study-I).

    PubMed

    Reddy, Varikasuvu Seshadri; Bukke, Suman; Dutt, Naveen; Rana, Puneet; Pandey, Arun Kumar

    2017-07-01

    Available studies in the literature on the selenium levels in Alzheimer's disease (AD) are inconsistent with some studies reporting its decrease in the circulation, while others reported an increase or no change as compared to controls. The objective of this study was to perform a meta-analysis of circulatory (plasma/serum and blood), erythrocyte and cerebrospinal fluid (CSF) selenium levels in AD compared controls. We also performed a meta-analysis of the correlation coefficients (r) to demonstrate the associations between selenium and glutathione peroxidase (GPx) in AD patients. All major databases were searched for eligible studies. We included 12 case-control/observational studies reporting selenium concentrations in AD and controls. Pooled-overall effect size as standardized mean difference (SMD) and pooled r-values were generated using Review Manager 5.3 and MedCalc 15.8 software. Random-effects meta-analysis indicated a decrease in circulatory (SMD=-0.44), erythrocellular (SMD=-0.52) and CSF (SMD=-0.14) selenium levels in AD patients compared to controls. Stratified meta-analysis demonstrated that the selenium levels were decreased in both the subgroups with (SMD=-0.55) and without (SMD=-0.37) age matching between AD and controls. Our results also demonstrated a direct association between decreased selenium levels and GPx in AD. This meta-analysis suggests that circulatory selenium concentration is significantly lower in AD patients compared to controls and this decrease in selenium is directly correlated with an important antioxidant enzyme, the GPx, in AD. Copyright © 2017 Elsevier GmbH. All rights reserved.

  13. A systematic review and meta-analysis of the proportion of dogs surrendered for dog-related and owner-related reasons.

    PubMed

    Lambert, Kim; Coe, Jason; Niel, Lee; Dewey, Cate; Sargeant, Jan M

    2015-01-01

    Companion-animal relinquishment is a worldwide phenomenon that leaves companion animals homeless. Knowing why humans make the decision to end their relationship with a companion-animal can help in our understanding of this complex societal issue and can help to develop preventive strategies. A systematic review and meta-analysis was conducted to summarize reasons why dogs are surrendered, and determine if certain study characteristics were associated with the reported proportions of reasons for surrender. Articles investigating one or more reasons for dog surrender were selected from the references of a published scoping review. Two reviewers assessed the titles and abstracts of these articles, identifying 39 relevant articles. From these, 21 articles were further excluded because of ineligible study design, insufficient data available for calculating a proportion, or no data available for dogs. Data were extracted from 18 articles and meta-analysis was conducted on articles investigating reasons for dog surrender to a shelter (n=9) or dog surrender for euthanasia (n=5). Three studies were excluded from meta-analysis because they were duplicate populations. Other reasons for excluding studies from meta-analysis were, (1) the study only investigated reasons for dog re-relinquishment (n=2) and (2) the study sample size was <10 (n=1). Two articles investigated reasons for both dog surrender to a shelter and dog surrender for euthanasia. Results of meta-analysis found owner health/illness as a reason for dog surrender to a shelter had an overall estimate of 4.6% (95% CI: 4.1%, 5.2%). For all other identified reasons for surrender there was significant variation in methodology among studies preventing further meta-analysis. Univariable meta-regression was conducted to explore sources of variation among these studies. Country was identified as a significant source of variation (p<0.01) among studies reporting behavioural problems as a reason for dog surrender for euthanasia. The overall estimate for studies from Australia was 10% (95% CI: 8.0%, 12.0%; I(2)=15.5%), compared to 16% (95% CI: 15.0%, 18.0%; I(2)=20.2%) for studies from other countries. The present systematic review and meta-analysis highlights the need for further research and standardization of data collection to improve understanding of the reasons for dog relinquishment. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. CMS Analysis and Data Reduction with Apache Spark

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gutsche, Oliver; Canali, Luca; Cremer, Illia

    Experimental Particle Physics has been at the forefront of analyzing the world's largest datasets for decades. The HEP community was among the first to develop suitable software and computing tools for this task. In recent times, new toolkits and systems for distributed data processing, collectively called "Big Data" technologies have emerged from industry and open source projects to support the analysis of Petabyte and Exabyte datasets in industry. While the principles of data analysis in HEP have not changed (filtering and transforming experiment-specific data formats), these new technologies use different approaches and tools, promising a fresh look at analysis ofmore » very large datasets that could potentially reduce the time-to-physics with increased interactivity. Moreover these new tools are typically actively developed by large communities, often profiting of industry resources, and under open source licensing. These factors result in a boost for adoption and maturity of the tools and for the communities supporting them, at the same time helping in reducing the cost of ownership for the end-users. In this talk, we are presenting studies of using Apache Spark for end user data analysis. We are studying the HEP analysis workflow separated into two thrusts: the reduction of centrally produced experiment datasets and the end-analysis up to the publication plot. Studying the first thrust, CMS is working together with CERN openlab and Intel on the CMS Big Data Reduction Facility. The goal is to reduce 1 PB of official CMS data to 1 TB of ntuple output for analysis. We are presenting the progress of this 2-year project with first results of scaling up Spark-based HEP analysis. Studying the second thrust, we are presenting studies on using Apache Spark for a CMS Dark Matter physics search, comparing Spark's feasibility, usability and performance to the ROOT-based analysis.« less

  15. Hypothyroidism as a risk factor for open angle glaucoma: A systematic review and meta-analysis

    PubMed Central

    Liu, Yue; Zheng, Guangying

    2017-01-01

    Purpose The relationship between hypothyroidism and primary open angle glaucoma (POAG) has attracted intense interest recently, but the reported results have been controversial. This meta-analysis was carried out to determine the association between hypothyroidism and POAG. Methods The literature was identified from three databases (Web of Science, Embase, and PubMed). The meta-analyses were performed using random-effects models, with results reported as adjusted odds ratios (ORs) with 95% confidence intervals (CI 95%). Results A total of 11 studies meeting the inclusion criteria were included in the final meta-analysis. The pooled OR based on 11 risk estimates showed a statistically significant increased risk of POAG prevalence among individuals with hypothyroidism (OR = 1.64, 95% CI = 1.27–2.13). Substantial heterogeneity among these studies was detected (P < 0.001; I2 = 83.2%). Sub-group analysis revealed that the cohort studies and case–control studies showed a significant association between hypothyroidism and POAG, which was not observed in cross-sectional studies. There was no significant publication bias in this study. Conclusions The findings of this meta-analysis indicate that individuals with hypothyroidism have an increased risk of developing POAG. PMID:29069095

  16. Behavior analytic approaches to problem behavior in intellectual disabilities.

    PubMed

    Hagopian, Louis P; Gregory, Meagan K

    2016-03-01

    The purpose of the current review is to summarize recent behavior analytic research on problem behavior in individuals with intellectual disabilities. We have focused our review on studies published from 2013 to 2015, but also included earlier studies that were relevant. Behavior analytic research on problem behavior continues to focus on the use and refinement of functional behavioral assessment procedures and function-based interventions. During the review period, a number of studies reported on procedures aimed at making functional analysis procedures more time efficient. Behavioral interventions continue to evolve, and there were several larger scale clinical studies reporting on multiple individuals. There was increased attention on the part of behavioral researchers to develop statistical methods for analysis of within subject data and continued efforts to aggregate findings across studies through evaluative reviews and meta-analyses. Findings support continued utility of functional analysis for guiding individualized interventions and for classifying problem behavior. Modifications designed to make functional analysis more efficient relative to the standard method of functional analysis were reported; however, these require further validation. Larger scale studies on behavioral assessment and treatment procedures provided additional empirical support for effectiveness of these approaches and their sustainability outside controlled clinical settings.

  17. User-Centered Iterative Design of a Collaborative Virtual Environment

    DTIC Science & Technology

    2001-03-01

    cognitive task analysis methods to study land navigators. This study was intended to validate the use of user-centered design methodologies for the design of...have explored the cognitive aspects of collaborative human way finding and design for collaborative virtual environments. Further investigation of design paradigms should include cognitive task analysis and behavioral task analysis.

  18. The Analysis of Detective Genre in Media Studies in the Student Audience

    ERIC Educational Resources Information Center

    Fedorov, Alexander

    2011-01-01

    Development of skills for the critical analysis of media texts--an important task of media education. However, media literacy practice shows that students have the problems with the discussion/analysis of entertainment genres in the early stages of media studies, for example, the difficulties in the process of understanding and interpreting the…

  19. Collection, handling and analysis of specimens for studies of mucosal immunity in animals of veterinary importance - Appendix III

    USDA-ARS?s Scientific Manuscript database

    The validity of data in science depends on the reliability of the collection procedure and the methods used for data analysis. This becomes a major challenge in studies of mucosal immunology since samples for analysis come from various anatomical sources which differ remarkably in their content and ...

  20. The Construct Validity of Scores on a Japanese Version of the Perceptual Component of the Style Analysis Survey

    ERIC Educational Resources Information Center

    Isemonger, Ian; Watanabe, Kaoru

    2007-01-01

    This study examines the psychometrics of the perceptual component of the Style Analysis Survey (SAS) [Oxford, R.L., 1993a. "Style Analysis Survey (SAS)." University of Alabama, Tuscaloosa, AL]. The study is conducted in the context of questions over another perceptual learning-styles instrument, the "Perceptual Learning Styles Preferences…

  1. The Hard but Necessary Task of Gathering Order-One Effect Size Indices in Meta-Analysis

    ERIC Educational Resources Information Center

    Ortego, Carmen; Botella, Juan

    2010-01-01

    Meta-analysis of studies with two groups and two measurement occasions must employ order-one effect size indices to represent study outcomes. Especially with non-random assignment, non-equivalent control group designs, a statistical analysis restricted to post-treatment scores can lead to severely biased conclusions. The 109 primary studies…

  2. Effectiveness of Various Innovative Learning Methods in Health Science Classrooms: A Meta-Analysis

    ERIC Educational Resources Information Center

    Kalaian, Sema A.; Kasim, Rafa M.

    2017-01-01

    This study reports the results of a meta-analysis of the available literature on the effectiveness of various forms of innovative small-group learning methods on student achievement in undergraduate college health science classrooms. The results of the analysis revealed that most of the primary studies supported the effectiveness of the…

  3. Object motion analysis study

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The use of optical data processing (ODP) techniques for motion analysis in two-dimensional imagery was studied. The basic feasibility of this approach was demonstrated, but inconsistent performance of the photoplastic used for recording spatial filters prevented totally automatic operation. Promising solutions to the problems encountered are discussed, and it is concluded that ODP techniques could be quite useful for motion analysis.

  4. Improving Skill Development: An Exploratory Study Comparing a Philosophical and an Applied Ethical Analysis Technique

    ERIC Educational Resources Information Center

    Al-Saggaf, Yeslam; Burmeister, Oliver K.

    2012-01-01

    This exploratory study compares and contrasts two types of critical thinking techniques; one is a philosophical and the other an applied ethical analysis technique. The two techniques analyse an ethically challenging situation involving ICT that a recent media article raised to demonstrate their ability to develop the ethical analysis skills of…

  5. Psychometric Properties and Factorial Structure of the Chinese Version of the Gratitude Resentment and Appreciation Test

    ERIC Educational Resources Information Center

    Lin, Shu-Hui; Huang, Yun-Chen

    2016-01-01

    The purpose of this study was to validate a Chinese version of the Gratitude Resentment and Appreciation Test (GRAT) with Taiwanese students. In Study 1, a total of 2511 Taiwanese students participated and completed the translated GRAT. Exploratory factor analysis, confirmatory factor analysis and reliability analysis were undertaken to assess the…

  6. The Limits of Outcomes Analysis; A Comment on "Sex Discrimination in Higher Employment: An Empirical Analysis of the Case Law."

    ERIC Educational Resources Information Center

    Lee, Barbara A.

    1990-01-01

    Questions assumptions by Schoenfeld and Zirkel in a study reviewing gender discrimination cases against institutions of higher education. Critiques the methodology used in that study, cautions about the overall utility of "outcomes analysis," and reports more promising routes of empirical legal research. (15 references) (MLF)

  7. Evaluating Language Environment Analysis System Performance for Chinese: A Pilot Study in Shanghai

    ERIC Educational Resources Information Center

    Gilkerson, Jill; Zhang, Yiwen; Xu, Dongxin; Richards, Jeffrey A.; Xu, Xiaojuan; Jiang, Fan; Harnsberger, James; Topping, Keith

    2015-01-01

    Purpose: The purpose of this study was to evaluate performance of the Language Environment Analysis (LENA) automated language-analysis system for the Chinese Shanghai dialect and Mandarin (SDM) languages. Method: Volunteer parents of 22 children aged 3-23 months were recruited in Shanghai. Families provided daylong in-home audio recordings using…

  8. Efficacy of Virtual Patients in Medical Education: A Meta-Analysis of Randomized Studies

    ERIC Educational Resources Information Center

    Consorti, Fabrizio; Mancuso, Rosaria; Nocioni, Martina; Piccolo, Annalisa

    2012-01-01

    A meta-analysis was performed to assess the Effect Size (ES) from randomized studies comparing the effect of educational interventions in which Virtual patients (VPs) were used either as an alternative method or additive to usual curriculum versus interventions based on more traditional methods. Meta-analysis was designed, conducted and reported…

  9. Exploring Advertising in Higher Education: An Empirical Analysis in North America, Europe, and Japan

    ERIC Educational Resources Information Center

    Papadimitriou, Antigoni; Blanco Ramírez, Gerardo

    2015-01-01

    This empirical study explores higher education advertising campaigns displayed in five world cities: Boston, New York, Oslo, Tokyo, and Toronto. The study follows a mixed-methods research design relying on content analysis and multimodal semiotic analysis and employs a conceptual framework based on the knowledge triangle of education, research,…

  10. Family Early Literacy Practices Questionnaire: A Validation Study for a Spanish-Speaking Population

    ERIC Educational Resources Information Center

    Lewis, Kandia

    2012-01-01

    The purpose of the current study was to evaluate the psychometric validity of a Spanish translated version of a family involvement questionnaire (the FELP) using a mixed-methods design. Thus, statistical analyses (i.e., factor analysis, reliability analysis, and item analysis) and qualitative analyses (i.e., focus group data) were assessed.…

  11. An Analysis of the Teaching of Critical Thinking Skills in History in Postsecondary Education

    ERIC Educational Resources Information Center

    Arrington, Walter T. Ted

    2017-01-01

    This study is an investigation and analysis of the teaching of critical thinking skills in eight public universities in Texas, in particular the History, Education, and Business departments. The study is, in part, a document analysis of the universities' mission statements, the departments' stated learning objectives, and two upper level…

  12. Mass Media Representation of Teaching: A Behaviour Analysis Approach.

    ERIC Educational Resources Information Center

    Hobbs, Sandy; Mackie, Stirling

    Although psychological studies of the mass media have been dominated by cognitivist and psychodynamic concepts, a study of the mass media using a behavior analysis method may be used to analyze the content of the mass media. By applying that analysis to fictional teacher-learner interactions an interpretation of those relationships can be made and…

  13. National Job Corps Study: Report on the Process Analysis. Research and Evaluation Report Series.

    ERIC Educational Resources Information Center

    Johnson, Terry; Gritz, Mark; Jackson, Russell; Burghardt, John; Boussy, Carol; Leonard, Jan; Orians, Carlyn

    This report presents results of a process analysis that describes and documents Job Corps services and operations. Chapter one provides overviews of Job Corps, the national Job Corps study, and the process analysis. Chapter two describes the administrative structure of Job Corps and presents data on the geographic distribution and characteristics…

  14. English Language Needs Analysis of Qur'anic Sciences and Tradition Students in Iran

    ERIC Educational Resources Information Center

    Salehi, Hadi; Davari, Ameneh; Yunus, Melor Md

    2015-01-01

    Needs analysis is fundamental to determine what students need to achieve through the medium of English accurately analysis. In this regard, the present study seeks to evaluate the ESP course book entitled "The ESP Course of Qur'anic Sciences and Tradition" taught at some universities in Iran. More specifically, the study aims to identify…

  15. A Discursive Formation that Undermined Integration at a Historically Advantaged School in South Africa

    ERIC Educational Resources Information Center

    Naidoo, Devika

    2010-01-01

    This paper provides an analysis of the extent of integration at a historically advantaged school. A qualitative multi-method case study allowed for in-depth analysis of integration in the school. Bernstein's theory of code, classification, boundary and power framed the study. Data analysis showed that: racial desegregation was achieved at student…

  16. An Analysis of Corporal Punishment Practices in the State of Mississippi

    ERIC Educational Resources Information Center

    Williams-Damond, Twyla A.

    2014-01-01

    The focus of this research mainly centers on a quantitative descriptive overview of corporal punishment practices in the state of Mississippi, but this study also includes a legal document analysis component. This study forms the Mississippi portion of a comprehensive analysis of the demographics of corporal punishment in the public schools of the…

  17. Space transfer concepts and analysis for exploration missions

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Covered here is the second phase of a broad scoped and systematic study of space transfer concepts for human lunar and Mars missions. The study addressed issues that were raised during Phase 1, developed generic Mars missions profile analysis data, and conducted preliminary analysis of the Mars in-space transportation requirements and implementation from the Stafford Committee Synthesis Report.

  18. A Factor Analysis of Peking Opera: Its Functions in Mass Communications.

    ERIC Educational Resources Information Center

    Cheng, Philip H.

    The study reported in this paper examined the structure and function of Chinese opera (also known as Peking opera) as an effective communication medium of social control and change in China, a land populated by 800 million people and nourished by a 5,000-year-old civilization. The study followed structural-functional analysis, content analysis,…

  19. Concept Maps as Instructional Tools for Improving Learning of Phase Transitions in Object-Oriented Analysis and Design

    ERIC Educational Resources Information Center

    Shin, Shin-Shing

    2016-01-01

    Students attending object-oriented analysis and design (OOAD) courses typically encounter difficulties transitioning from requirements analysis to logical design and then to physical design. Concept maps have been widely used in studies of user learning. The study reported here, based on the relationship of concept maps to learning theory and…

  20. Space shuttle navigation analysis. Volume 2: Baseline system navigation

    NASA Technical Reports Server (NTRS)

    Jones, H. L.; Luders, G.; Matchett, G. A.; Rains, R. G.

    1980-01-01

    Studies related to the baseline navigation system for the orbiter are presented. The baseline navigation system studies include a covariance analysis of the Inertial Measurement Unit calibration and alignment procedures, postflight IMU error recovery for the approach and landing phases, on-orbit calibration of IMU instrument biases, and a covariance analysis of entry and prelaunch navigation system performance.

  1. Meta-Analysis of Planetarium Efficacy Research

    ERIC Educational Resources Information Center

    Brazell, Bruce D.; Espinoza, Sue

    2009-01-01

    In this study, the instructional effectiveness of the planetarium in astronomy education was explored through a meta-analysis of 19 studies. This analysis resulted in a heterogeneous distribution of 24 effect sizes with a mean of +0.28, p less than 0.05. The variability in this distribution was not fully explained under a fixed effect model. As a…

  2. Technology's Effect on Achievement in Higher Education: A Stage I Meta-Analysis of Classroom Applications

    ERIC Educational Resources Information Center

    Schmid, Richard F.; Bernard, Robert M.; Borokhovski, Eugene; Tamim, Rana; Abrami, Philip C.; Wade, C. Anne; Surkes, Michael A.; Lowerison, Gretchen

    2009-01-01

    This paper reports the findings of a Stage I meta-analysis exploring the achievement effects of computer-based technology use in higher education classrooms (non-distance education). An extensive literature search revealed more than 6,000 potentially relevant primary empirical studies. Analysis of a representative sample of 231 studies (k = 310)…

  3. Development of the Spatial Ability Test for Middle School Students

    ERIC Educational Resources Information Center

    Yildiz, Sevda Göktepe; Özdemir, Ahmet Sükrü

    2017-01-01

    The purpose of this study was to develop a test to determine spatial ability of middle school students. The participants were 704 middle school students (6th, 7th and 8th grade) who were studying at different schools from Istanbul. Item analysis, exploratory and confirmatory factor analysis, reliability analysis were used to analyse the data.…

  4. Vibration Transmission through Rolling Element Bearings in Geared Rotor Systems

    DTIC Science & Technology

    1990-11-01

    147 4.8 Concluding Remarks ........................................................... 153 V STATISTICAL ENERGY ANALYSIS ............................................ 155...and dynamic finite element techniques are used to develop the discrete vibration models while statistical energy analysis method is used for the broad...bearing system studies, geared rotor system studies, and statistical energy analysis . Each chapter is self sufficient since it is written in a

  5. Preliminary Rural Analysis of the Early Childhood Longitudinal Study--Kindergarten Cohort. Rural Early Childhood Brief Number 2

    ERIC Educational Resources Information Center

    National Center for Rural Early Childhood Learning Initiatives - Mississippi State University Early Childhood Institute, 2005

    2005-01-01

    This brief introduces the first results from a rural analysis of selected national datasets. Provided are key findings concerning kindergarten readiness of rural children from an analysis of the Kindergarten Cohort of the Early Childhood Longitudinal Study (ECLS). Future briefs will summarize the findings concerning the health of the Kindergarten…

  6. Evidence-based mapping of design heterogeneity prior to meta-analysis: a systematic review and evidence synthesis.

    PubMed

    Althuis, Michelle D; Weed, Douglas L; Frankenfeld, Cara L

    2014-07-23

    Assessment of design heterogeneity conducted prior to meta-analysis is infrequently reported; it is often presented post hoc to explain statistical heterogeneity. However, design heterogeneity determines the mix of included studies and how they are analyzed in a meta-analysis, which in turn can importantly influence the results. The goal of this work is to introduce ways to improve the assessment and reporting of design heterogeneity prior to statistical summarization of epidemiologic studies. In this paper, we use an assessment of sugar-sweetened beverages (SSB) and type 2 diabetes (T2D) as an example to show how a technique called 'evidence mapping' can be used to organize studies and evaluate design heterogeneity prior to meta-analysis.. Employing a systematic and reproducible approach, we evaluated the following elements across 11 selected cohort studies: variation in definitions of SSB, T2D, and co-variables, design features and population characteristics associated with specific definitions of SSB, and diversity in modeling strategies. Evidence mapping strategies effectively organized complex data and clearly depicted design heterogeneity. For example, across 11 studies of SSB and T2D, 7 measured diet only once (with 7 to 16 years of disease follow-up), 5 included primarily low SSB consumers, and 3 defined the study variable (SSB) as consumption of either sugar or artificially-sweetened beverages. This exercise also identified diversity in analysis strategies, such as adjustment for 11 to 17 co-variables and a large degree of fluctuation in SSB-T2D risk estimates depending on variables selected for multivariable models (2 to 95% change in the risk estimate from the age-adjusted model). Meta-analysis seeks to understand heterogeneity in addition to computing a summary risk estimate. This strategy effectively documents design heterogeneity, thus improving the practice of meta-analysis by aiding in: 1) protocol and analysis planning, 2) transparent reporting of differences in study designs, and 3) interpretation of pooled estimates. We recommend expanding the practice of meta-analysis reporting to include a table that summarizes design heterogeneity. This would provide readers with more evidence to interpret the summary risk estimates.

  7. Evidence-based mapping of design heterogeneity prior to meta-analysis: a systematic review and evidence synthesis

    PubMed Central

    2014-01-01

    Background Assessment of design heterogeneity conducted prior to meta-analysis is infrequently reported; it is often presented post hoc to explain statistical heterogeneity. However, design heterogeneity determines the mix of included studies and how they are analyzed in a meta-analysis, which in turn can importantly influence the results. The goal of this work is to introduce ways to improve the assessment and reporting of design heterogeneity prior to statistical summarization of epidemiologic studies. Methods In this paper, we use an assessment of sugar-sweetened beverages (SSB) and type 2 diabetes (T2D) as an example to show how a technique called ‘evidence mapping’ can be used to organize studies and evaluate design heterogeneity prior to meta-analysis.. Employing a systematic and reproducible approach, we evaluated the following elements across 11 selected cohort studies: variation in definitions of SSB, T2D, and co-variables, design features and population characteristics associated with specific definitions of SSB, and diversity in modeling strategies. Results Evidence mapping strategies effectively organized complex data and clearly depicted design heterogeneity. For example, across 11 studies of SSB and T2D, 7 measured diet only once (with 7 to 16 years of disease follow-up), 5 included primarily low SSB consumers, and 3 defined the study variable (SSB) as consumption of either sugar or artificially-sweetened beverages. This exercise also identified diversity in analysis strategies, such as adjustment for 11 to 17 co-variables and a large degree of fluctuation in SSB-T2D risk estimates depending on variables selected for multivariable models (2 to 95% change in the risk estimate from the age-adjusted model). Conclusions Meta-analysis seeks to understand heterogeneity in addition to computing a summary risk estimate. This strategy effectively documents design heterogeneity, thus improving the practice of meta-analysis by aiding in: 1) protocol and analysis planning, 2) transparent reporting of differences in study designs, and 3) interpretation of pooled estimates. We recommend expanding the practice of meta-analysis reporting to include a table that summarizes design heterogeneity. This would provide readers with more evidence to interpret the summary risk estimates. PMID:25055879

  8. Serum Uric Acid Levels and Diabetic Peripheral Neuropathy in Type 2 Diabetes: a Systematic Review and Meta-analysis.

    PubMed

    Yu, Shuai; Chen, Ying; Hou, Xu; Xu, Donghua; Che, Kui; Li, Changgui; Yan, Shengli; Wang, Yangang; Wang, Bin

    2016-03-01

    Previous studies suggested a possible association between serum uric acid levels and peripheral neuropathy in patients with type 2 diabetes, but no definite evidence was available. A systematic review and meta-analysis of relevant studies were performed to comprehensively estimate the association. Pubmed, Web of Science, Embase, and China Biology Medicine (CBM) databases were searched for eligible studies. Study-specific data were combined using random-effect or fixed-effect models of meta-analysis according to between-study heterogeneity. Twelve studies were finally included into the meta-analysis, which involved a total of 1388 type 2 diabetic patients with peripheral neuropathy and 4746 patients without peripheral neuropathy. Meta-analysis showed that there were obvious increased serum uric acid levels in diabetic patients with peripheral neuropathy (weighted mean difference [WMD] = 50.03 μmol/L, 95% confidence interval [95%CI] 22.14-77.93, P = 0.0004). Hyperuricemia was also significantly associated with increased risk of peripheral neuropathy in patients with type 2 diabetes (risk ratio [RR] = 2.83, 95%CI 2.13-3.76, P < 0.00001). Meta-analysis of two studies with adjusted risk estimates showed that hyperuricemia was independently associated with increased risk of peripheral neuropathy in type 2 diabetic patients (RR = 1.95, 95%CI 1.23-3.11, P = 0.005). Type 2 diabetic patients with peripheral neuropathy have obvious increased serum uric acid levels, and hyperuricemia is associated with increased risk of peripheral neuropathy. Further prospective cohort studies are needed to validate the impact of serum uric acid levels on peripheral neuropathy risk.

  9. Glutathione S-transferase M1 polymorphism and endometriosis susceptibility: a meta-analysis.

    PubMed

    Li, H; Zhang, Y

    2015-02-01

    Many studies have investigated the association between glutathione S-transferase M1 (GSTM1) null genotype and the risk of endometriosis. However, the effect of the GSTM1 null genotype on endometriosis is still unclear because of apparent inconsistencies among those studies. A meta-analysis was performed to characterize the relationship more accurately. PubMed, Embase, and Web of Science were searched. To derive a more precise estimation of the relationship, a meta-analysis was performed. We estimated the summary odds ratio (OR) with a 95% confidence interval (95% CI) to assess the association. Up to 24 case-control studies with 2,684 endometriosis cases and 3,119 control cases were included into this meta-analysis. Meta-analysis of the 24 studies showed that GSTM1 null genotype was associated with the risk of endometriosis (random effects OR=1.66, 95% CI 1.23 to 2.24). In the subgroup analysis by ethnicity, increased risks were found for both Caucasians (OR=1.26, 95% CI 1.04-1.51) and Asians (OR=1.28, 95% CI 1.06-1.55). No evidence of publication bias was observed. In conclusion, this meta-analysis suggests that the GSTM1 null genotype increases the overall risk of endometriosis. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  10. Estimation of low back moments from video analysis: a validation study.

    PubMed

    Coenen, Pieter; Kingma, Idsart; Boot, Cécile R L; Faber, Gert S; Xu, Xu; Bongers, Paulien M; van Dieën, Jaap H

    2011-09-02

    This study aimed to develop, compare and validate two versions of a video analysis method for assessment of low back moments during occupational lifting tasks since for epidemiological studies and ergonomic practice relatively cheap and easily applicable methods to assess low back loads are needed. Ten healthy subjects participated in a protocol comprising 12 lifting conditions. Low back moments were assessed using two variants of a video analysis method and a lab-based reference method. Repeated measures ANOVAs showed no overall differences in peak moments between the two versions of the video analysis method and the reference method. However, two conditions showed a minor overestimation of one of the video analysis method moments. Standard deviations were considerable suggesting that errors in the video analysis were random. Furthermore, there was a small underestimation of dynamic components and overestimation of the static components of the moments. Intraclass correlations coefficients for peak moments showed high correspondence (>0.85) of the video analyses with the reference method. It is concluded that, when a sufficient number of measurements can be taken, the video analysis method for assessment of low back loads during lifting tasks provides valid estimates of low back moments in ergonomic practice and epidemiological studies for lifts up to a moderate level of asymmetry. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Analytical Round Robin for Elastic-Plastic Analysis of Surface Cracked Plates: Phase I Results

    NASA Technical Reports Server (NTRS)

    Wells, D. N.; Allen, P. A.

    2012-01-01

    An analytical round robin for the elastic-plastic analysis of surface cracks in flat plates was conducted with 15 participants. Experimental results from a surface crack tension test in 2219-T8 aluminum plate provided the basis for the inter-laboratory study (ILS). The study proceeded in a blind fashion given that the analysis methodology was not specified to the participants, and key experimental results were withheld. This approach allowed the ILS to serve as a current measure of the state of the art for elastic-plastic fracture mechanics analysis. The analytical results and the associated methodologies were collected for comparison, and sources of variability were studied and isolated. The results of the study revealed that the J-integral analysis methodology using the domain integral method is robust, providing reliable J-integral values without being overly sensitive to modeling details. General modeling choices such as analysis code, model size (mesh density), crack tip meshing, or boundary conditions, were not found to be sources of significant variability. For analyses controlled only by far-field boundary conditions, the greatest source of variability in the J-integral assessment is introduced through the constitutive model. This variability can be substantially reduced by using crack mouth opening displacements to anchor the assessment. Conclusions provide recommendations for analysis standardization.

  12. Multivariate meta-analysis with an increasing number of parameters.

    PubMed

    Boca, Simina M; Pfeiffer, Ruth M; Sampson, Joshua N

    2017-05-01

    Meta-analysis can average estimates of multiple parameters, such as a treatment's effect on multiple outcomes, across studies. Univariate meta-analysis (UVMA) considers each parameter individually, while multivariate meta-analysis (MVMA) considers the parameters jointly and accounts for the correlation between their estimates. The performance of MVMA and UVMA has been extensively compared in scenarios with two parameters. Our objective is to compare the performance of MVMA and UVMA as the number of parameters, p, increases. Specifically, we show that (i) for fixed-effect (FE) meta-analysis, the benefit from using MVMA can substantially increase as p increases; (ii) for random effects (RE) meta-analysis, the benefit from MVMA can increase as p increases, but the potential improvement is modest in the presence of high between-study variability and the actual improvement is further reduced by the need to estimate an increasingly large between study covariance matrix; and (iii) when there is little to no between-study variability, the loss of efficiency due to choosing RE MVMA over FE MVMA increases as p increases. We demonstrate these three features through theory, simulation, and a meta-analysis of risk factors for non-Hodgkin lymphoma. © Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  13. A comparison study on detection of key geochemical variables and factors through three different types of factor analysis

    NASA Astrophysics Data System (ADS)

    Hoseinzade, Zohre; Mokhtari, Ahmad Reza

    2017-10-01

    Large numbers of variables have been measured to explain different phenomena. Factor analysis has widely been used in order to reduce the dimension of datasets. Additionally, the technique has been employed to highlight underlying factors hidden in a complex system. As geochemical studies benefit from multivariate assays, application of this method is widespread in geochemistry. However, the conventional protocols in implementing factor analysis have some drawbacks in spite of their advantages. In the present study, a geochemical dataset including 804 soil samples collected from a mining area in central Iran in order to search for MVT type Pb-Zn deposits was considered to outline geochemical analysis through various fractal methods. Routine factor analysis, sequential factor analysis, and staged factor analysis were applied to the dataset after opening the data with (additive logratio) alr-transformation to extract mineralization factor in the dataset. A comparison between these methods indicated that sequential factor analysis has more clearly revealed MVT paragenesis elements in surface samples with nearly 50% variation in F1. In addition, staged factor analysis has given acceptable results while it is easy to practice. It could detect mineralization related elements while larger factor loadings are given to these elements resulting in better pronunciation of mineralization.

  14. A primer on the study of transitory dynamics in ecological series using the scale-dependent correlation analysis.

    PubMed

    Rodríguez-Arias, Miquel Angel; Rodó, Xavier

    2004-03-01

    Here we describe a practical, step-by-step primer to scale-dependent correlation (SDC) analysis. The analysis of transitory processes is an important but often neglected topic in ecological studies because only a few statistical techniques appear to detect temporary features accurately enough. We introduce here the SDC analysis, a statistical and graphical method to study transitory processes at any temporal or spatial scale. SDC analysis, thanks to the combination of conventional procedures and simple well-known statistical techniques, becomes an improved time-domain analogue of wavelet analysis. We use several simple synthetic series to describe the method, a more complex example, full of transitory features, to compare SDC and wavelet analysis, and finally we analyze some selected ecological series to illustrate the methodology. The SDC analysis of time series of copepod abundances in the North Sea indicates that ENSO primarily is the main climatic driver of short-term changes in population dynamics. SDC also uncovers some long-term, unexpected features in the population. Similarly, the SDC analysis of Nicholson's blowflies data locates where the proposed models fail and provides new insights about the mechanism that drives the apparent vanishing of the population cycle during the second half of the series.

  15. Fixed Route Comprehensive Operational Analysis, 1994 Operating Year. Fourth Installment Route 3: Mill Ridge/Mill Plain Analysis

    DOT National Transportation Integrated Search

    1995-05-01

    In October, of 1992, the Housatonic Area Regional Transit (HART) District published a planning study providing an in-depth analysis of its fixed route bus transit service. This comprehensive operational analysis (COA) was the first detailed analysis ...

  16. Fixed Route Comprehensive Operational Analysis, 1994 Operating Year. First Installment, Route 1: Medical Center/Golden Hill Analysis

    DOT National Transportation Integrated Search

    1994-07-01

    In October, of 1992, the Housatonic Area Regional Transit (HART) District published a planning study providing an in-depth analysis of its fixed route bus transit service. This comprehensive operational analysis (COA) was the first detailed analysis ...

  17. Fixed Route Comprehensive Operational Analysis, 1994 Operating Year. Third Installment, Route 6: Lake Avenue/Danbury Fair Mall Analysis

    DOT National Transportation Integrated Search

    1995-02-01

    In October, of 1992, the Housatonic Area Regional Transit (HART) District published a planning study providing an in-depth analysis of its fixed route bus transit service. This comprehensive operational analysis (COA) was the first detailed analysis ...

  18. Space Station Furnace Facility. Volume 2: Requirements Definition and Conceptual Design Study. Appendix 3: Environment Analysis. Volume 2; Appendix 3

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A Preliminary Safety Analysis (PSA) is being accomplished as part of the Space Station Furnace Facility (SSFF) contract. This analysis is intended to support SSFF activities by analyzing concepts and designs as they mature to develop essential safety requirements for inclusion in the appropriate specifications, and designs, as early as possible. In addition, the analysis identifies significant safety concerns that may warrant specific trade studies or design definition, etc. The analysis activity to date concentrated on hazard and hazard cause identification and requirements development with the goal of developing a baseline set of detailed requirements to support trade study, specifications development, and preliminary design activities. The analysis activity will continue as the design and concepts mature. Section 2 defines what was analyzed, but it is likely that the SSFF definitions will undergo further changes. The safety analysis activity will reflect these changes as they occur. The analysis provides the foundation for later safety activities. The hazards identified will in most cases have Preliminary Design Review (PDR) applicability. The requirements and recommendations developed for each hazard will be tracked to ensure proper and early resolution of safety concerns.

  19. The Serotonin Transporter Promoter Variant (5-HTTLPR), Stress, and Depression Meta-Analysis Revisited: Evidence of Genetic Moderation

    PubMed Central

    Karg, Katja; Burmeister, Margit; Shedden, Kerby; Sen, Srijan

    2013-01-01

    Context The initial report of an interaction between a serotonin transporter promoter polymorphism (5-HTTLPR) and stress in the development of depression is perhaps the best-known and most cited finding in psychiatric genetics. Two recent meta-analyses explored the studies seeking to replicate this initial report and concluded that the evidence did not support the presence of the interaction. However, even the larger of the meta-analyses included only 14 of the 56 studies that have explored the relationship between 5-HTTLPR, stress and depression. Objective We sought to perform a meta-analysis including all relevant studies assessing whether 5-HTTLPR moderates the relationship between stress and depression. Data Sources We identified relevant articles from previous meta-analyses and reviews and a PubMed database search. Study Selection We excluded two studies presenting data that were included in other, larger, studies already included in our meta-analysis to avoid duplicate counting of subjects. Data Extraction In order to perform a more inclusive meta-analysis, we used the Liptak-Stouffer Z-score method to combine findings of primary studies at the significance test level rather than raw data level. Results We included 54 studies and found strong evidence that 5-HTTLPR moderates the relationship between stress and depression, with the 5-HTTLPR s allele associated with an increased risk of developing depression under stress (p<0.0001). When restricting our analysis to the studies included in the previous meta-analyses, we found no evidence of association (Munafo studies p=0.16; Risch studies p=0.11). This suggests that the difference in results between previous meta-analyses and ours was not due to the difference in meta-analytic technique but instead to the expanded set of studies included in this analysis. Conclusions Contrary to the results of the smaller earlier meta-analyses, we find strong evidence that 5-HTTLPR moderates the relationship between stress and depression in the studies published to date. PMID:21199959

  20. Farber's Disease

    MedlinePlus

    ... of these disorders. Additional studies will emphasize the quantitative analysis of the central nervous system structure and ... of these disorders. Additional studies will emphasize the quantitative analysis of the central nervous system structure and ...

  1. Analysis of magnetometer data/wave signals in the Earth's magnetosphere

    NASA Technical Reports Server (NTRS)

    Engebretson, Mark J.

    1993-01-01

    Work on the reduction and analysis of Dynamics Explorer (DE) satellite magnetometer data with special emphasis on the ULF fluctuations and waves evident in such data is described. Research focused on the following: (1) studies of Pc 1 wave packets near the plasmapause; (2) satellite-ground pulsation study; (3) support for studies of ion energization processes; (4) search for Pc 1 wave events in 1981 DE 1 data; (5) study of Pc 3-5 events observed simultaneously by DE 1 and by AMPTE CCE; (6) support for studies of electromagnetic transients on DE 1; and (7) analysis of wave events induced by sudden impulses.

  2. Descriptive analysis of staff satisfaction and turnover intention in a Malaysian University

    NASA Astrophysics Data System (ADS)

    Sidik, Mohamad Hazeem; Hamid, Mohd Rashid Ab; Ibrahim, Abdullah

    2017-05-01

    This paper discussed the descriptive analysis of staff satisfaction in education organisation. This study employed a cross-sectional study involving a total of 1042 of respondents from a university in east coast of Malaysia. The survey covers six dimensions of staff satisfaction which are leadership, staff involvement, workload, self-development, working environment and communication. From the analysis of the mean score, it reveals that the staff enjoyed moderate level of satisfaction and the findings of the study generally support the past findings in the literature. This study paved the way for in-depth investigation towards staff satisfaction at the university under study.

  3. Preliminary phytochemical screening, Antibacterial potential and GC-MS analysis of two medicinal plant extracts.

    PubMed

    Vijayaram, Seerangaraj; Kannan, Suruli; Saravanan, Konda Mani; Vasantharaj, Seerangaraj; Sathiyavimal, Selvam; P, Palanisamy Senthilkumar

    2016-05-01

    The presence study was aimed to catalyze the primary metabolites and their confirmation by using GC-MS analysis and antibacterial potential of leaf extract of two important medicinal plant viz., Eucalyptus and Azadirachta indica. The antibacterial potential of the methanol leaf extract of the studied species was tested against Escherichia coli, Pseudomonas aeruginosa, Klebsiellap neumoniae, Streptococcus pyogens, Staphylococcus aureus using by agar well diffusion method. The higher zone of inhibition (16mm) was observed against the bacterium Pseudomonas aeruginosa at 100μl concentration of methanol leaf extract. Preliminary phytochemical analysis of studied species shows that presence of phytochemical compounds like steroids, phenolic compounds and flavonoids. GC-MS analysis confirms the occurrence of 20 different compounds in the methanol leaf extract of the both studied species.

  4. Failure mode effect analysis and fault tree analysis as a combined methodology in risk management

    NASA Astrophysics Data System (ADS)

    Wessiani, N. A.; Yoshio, F.

    2018-04-01

    There have been many studies reported the implementation of Failure Mode Effect Analysis (FMEA) and Fault Tree Analysis (FTA) as a method in risk management. However, most of the studies usually only choose one of these two methods in their risk management methodology. On the other side, combining these two methods will reduce the drawbacks of each methods when implemented separately. This paper aims to combine the methodology of FMEA and FTA in assessing risk. A case study in the metal company will illustrate how this methodology can be implemented. In the case study, this combined methodology will assess the internal risks that occur in the production process. Further, those internal risks should be mitigated based on their level of risks.

  5. Collaborative Study of Analysis of High Resolution Infrared Atmospheric Spectra Between NASA Langley Research Center and the University of Denver

    NASA Technical Reports Server (NTRS)

    Goldman, Aaron

    1999-01-01

    The Langley-D.U. collaboration on the analysis of high resolution infrared atmospheric spectra covered a number of important studies of trace gases identification and quantification from field spectra, and spectral line parameters analysis. The collaborative work included: Quantification and monitoring of trace gases from ground-based spectra available from various locations and seasons and from balloon flights. Studies toward identification and quantification of isotopic species, mostly oxygen and Sulfur isotopes. Search for new species on the available spectra. Update of spectroscopic line parameters, by combining laboratory and atmospheric spectra with theoretical spectroscopy methods. Study of trends of atmosphere trace constituents. Algorithms developments, retrievals intercomparisons and automatization of the analysis of NDSC spectra, for both column amounts and vertical profiles.

  6. Preliminary analysis of the National Crash Severity Study : factors in fatal accidents

    DOT National Transportation Integrated Search

    1979-06-01

    This study investigates the fatalities on the National Crash Severity Study (NCSS) of towaway, passenger car accidents. The analysis is in three stages. First, NCSS fatalities are compared to the fatally-injured occupants reported on the Fatal Accide...

  7. Validity and consistency assessment of accident analysis methods in the petroleum industry.

    PubMed

    Ahmadi, Omran; Mortazavi, Seyed Bagher; Khavanin, Ali; Mokarami, Hamidreza

    2017-11-17

    Accident analysis is the main aspect of accident investigation. It includes the method of connecting different causes in a procedural way. Therefore, it is important to use valid and reliable methods for the investigation of different causal factors of accidents, especially the noteworthy ones. This study aimed to prominently assess the accuracy (sensitivity index [SI]) and consistency of the six most commonly used accident analysis methods in the petroleum industry. In order to evaluate the methods of accident analysis, two real case studies (process safety and personal accident) from the petroleum industry were analyzed by 10 assessors. The accuracy and consistency of these methods were then evaluated. The assessors were trained in the workshop of accident analysis methods. The systematic cause analysis technique and bowtie methods gained the greatest SI scores for both personal and process safety accidents, respectively. The best average results of the consistency in a single method (based on 10 independent assessors) were in the region of 70%. This study confirmed that the application of methods with pre-defined causes and a logic tree could enhance the sensitivity and consistency of accident analysis.

  8. Similarity of markers identified from cancer gene expression studies: observations from GEO.

    PubMed

    Shi, Xingjie; Shen, Shihao; Liu, Jin; Huang, Jian; Zhou, Yong; Ma, Shuangge

    2014-09-01

    Gene expression profiling has been extensively conducted in cancer research. The analysis of multiple independent cancer gene expression datasets may provide additional information and complement single-dataset analysis. In this study, we conduct multi-dataset analysis and are interested in evaluating the similarity of cancer-associated genes identified from different datasets. The first objective of this study is to briefly review some statistical methods that can be used for such evaluation. Both marginal analysis and joint analysis methods are reviewed. The second objective is to apply those methods to 26 Gene Expression Omnibus (GEO) datasets on five types of cancers. Our analysis suggests that for the same cancer, the marker identification results may vary significantly across datasets, and different datasets share few common genes. In addition, datasets on different cancers share few common genes. The shared genetic basis of datasets on the same or different cancers, which has been suggested in the literature, is not observed in the analysis of GEO data. © The Author 2013. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  9. Understanding the variable effect of instructional innovations on student learning

    NASA Astrophysics Data System (ADS)

    Iverson, Heidi L.

    2012-02-01

    As a result of dissatisfaction with the traditional lecture-based model of education a large number of reform-oriented instructional innovations have been developed, enacted, and studied in undergraduate physics courses. While previous work has shown that the impact of instructional innovations on student learning has been overwhelmingly positive, it has also been highly variable. The purpose of this analysis is to investigate this variability. For this analysis, 79 published studies on undergraduate physics instructional innovations were analyzed with respect to the types of innovations used and the methodological characteristics of the studies themselves. The findings of this analysis have indicated that nearly half of the variability in effect size can be accounted for by study design characteristics rather than by the characteristics of the innovations used. However, a subsequent analysis illustrated that one specific innovation, Workshop/Studio Physics, appears to be particularly effective within the observed sample of studies.

  10. Spectroscopic analysis of solar and cosmic X-ray spectra. 1: The nature of cosmic X-ray spectra and proposed analytical techniques

    NASA Technical Reports Server (NTRS)

    Walker, A. B. C., Jr.

    1975-01-01

    Techniques for the study of the solar corona are reviewed as an introduction to a discussion of modifications required for the study of cosmic sources. Spectroscopic analysis of individual sources and the interstellar medium is considered. The latter was studied via analysis of its effect on the spectra of selected individual sources. The effects of various characteristics of the ISM, including the presence of grains, molecules, and ionization, are first discussed, and the development of ISM models is described. The expected spectral structure of individual cosmic sources is then reviewed with emphasis on supernovae remnants and binary X-ray sources. The observational and analytical requirements imposed by the characteristics of these sources are identified, and prospects for the analysis of abundances and the study of physical parameters within them are assessed. Prospects for the spectroscopic study of other classes of X-ray sources are also discussed.

  11. A Global Meta-Analysis of the Value of Ecosystem Services Provided by Lakes.

    PubMed

    Reynaud, Arnaud; Lanzanova, Denis

    2017-07-01

    This study presents the first meta-analysis on the economic value of ecosystem services delivered by lakes. A worldwide data set of 699 observations drawn from 133 studies combines information reported in primary studies with geospatial data. The meta-analysis explores antagonisms and synergies between ecosystem services. This is the first meta-analysis to incorporate simultaneously external geospatial data and ecosystem service interactions. We first show that it is possible to reliably predict the value of ecosystem services provided by lakes based on their physical and geographic characteristics. Second, we demonstrate that interactions between ecosystem services appear to be significant for explaining lake ecosystem service values. Third, we provide an estimation of the average value of ecosystem services provided by lakes: between 106 and 140 USD$2010 per respondent per year for non-hedonic price studies and between 169 and 403 USD$2010 per property per year for hedonic price studies.

  12. Polycystic ovary syndrome (PCOS) and the risk of coronary heart disease (CHD): a meta-analysis.

    PubMed

    Zhao, Luqian; Zhu, Zhigang; Lou, Huiling; Zhu, Guodong; Huang, Weimin; Zhang, Shaogang; Liu, Feng

    2016-06-07

    Some studies reported a significant association between polycystic ovary syndrome (PCOS) and risk of cardiovascular disease (CVD). However, the results are controversial. A systematic search was conducted in the PubMed, Science Direct, EMBASE, and Cochrane Library databases. Five case-control studies and 5 cohort studies were selected, involving a total of 104392 subjects in this meta-analysis. PCOS was significantly associated with the increased risk of CVD (OR = 1.30; 95% CI 1.09 - 1.56; P = 0.004). In the subgroup analysis of study design, both case-control studies and prospective cohort studies showed significant results (OR = 1.79; 95% CI 1.16 - 2.77; P = 0.009; OR = 1.20; 95% CI 1.06 - 1.37; P = 0.005), while retrospective cohort studies did not show positive result (OR = 0.91; 95% CI 0.60 - 1.40; P = 0.68). In a further stratified analysis by type of CVD, a significant association was found between PCOS and coronary heart disease (CHD) (OR = 1.44; 95% CI 1.13 - 1.84; P = 0.004). However, no significant association was observed between PCOS and myocardial infarction (MI) (OR = 1.01; 95% CI 0.68 - 1.51; P = 0.95). In conclusion, this meta-analysis suggested that PCOS is significantly associated with increased CHD risk.

  13. Studies on densification, mechanical, micro-structural and structure–properties relationship of magnesium aluminate spinel refractory aggregates prepared from Indian magnesite

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ghosh, Chandrima; Ghosh, Arup; Haldar, Manas Kamal, E-mail: manashaldar@cgcri.res.in

    The present work intends to study the development of magnesium aluminate spinel aggregates from Indian magnesite in a single firing stage. The raw magnesite has been evaluated in terms of chemical analysis, differential thermal analysis, thermogravimetric analysis, infrared spectroscopy, and X-ray diffraction. The experimental batch containing Indian magnesite and calcined alumina has been sintered in the temperature range of 1550 °C–1700 °C. The sintered material has been characterized in terms of physico-chemical properties like bulk density, apparent porosity, true density, relative density and thermo-mechanical/mechanical properties like hot modulus of rupture, thermal shock resistance, cold modulus of rupture and structural propertiesmore » by X-ray diffraction in terms of phase identification and evaluation of crystal structure parameters of corresponding phases by Rietveld analysis. The microstructures developed at different temperatures have been analyzed by field emission scanning electron microscope study and compositional analysis of the developed phase has been carried out by energy dispersive X-ray study. - Highlights: • The studies have been done to characterize the developed magnesium aluminate spinel. • The studies reveal correlation between refractory behavior of spinel and developed microstructures. • The studies show the values of lattice parameters of developed phases.« less

  14. The correlation between apparent diffusion coefficient and tumor cellularity in patients: a meta-analysis.

    PubMed

    Chen, Lihua; Liu, Min; Bao, Jing; Xia, Yunbao; Zhang, Jiuquan; Zhang, Lin; Huang, Xuequan; Wang, Jian

    2013-01-01

    To perform a meta-analysis exploring the correlation between the apparent diffusion coefficient (ADC) and tumor cellularity in patients. We searched medical and scientific literature databases for studies discussing the correlation between the ADC and tumor cellularity in patients. Only studies that were published in English or Chinese prior to November 2012 were considered for inclusion. Summary correlation coefficient (r) values were extracted from each study, and 95% confidence intervals (CIs) were calculated. Sensitivity and subgroup analyses were performed to investigate potential heterogeneity. Of 189 studies, 28 were included in the meta-analysis, comprising 729 patients. The pooled r for all studies was -0.57 (95% CI: -0.62, -0.52), indicating notable heterogeneity (P<0.001). After the sensitivity analysis, two studies were excluded, and the pooled r was -0.61 (95% CI: -0.66, -0.56) and was not significantly heterogeneous (P = 0.127). Regarding tumor type subgroup analysis, there were sufficient data to support a strong negative correlation between the ADC and cellularity for brain tumors. There was no notable evidence of publication bias. There is a strong negative correlation between the ADC and tumor cellularity in patients, particularly in the brain. However, larger, prospective studies are warranted to validate these findings in other cancer types.

  15. Cumulative meta-analysis: a new tool for detection of temporal trends and publication bias in ecology.

    PubMed Central

    Leimu, Roosa; Koricheva, Julia

    2004-01-01

    Temporal changes in the magnitude of research findings have recently been recognized as a general phenomenon in ecology, and have been attributed to the delayed publication of non-significant results and disconfirming evidence. Here we introduce a method of cumulative meta-analysis which allows detection of both temporal trends and publication bias in the ecological literature. To illustrate the application of the method, we used two datasets from recently conducted meta-analyses of studies testing two plant defence theories. Our results revealed three phases in the evolution of the treatment effects. Early studies strongly supported the hypothesis tested, but the magnitude of the effect decreased considerably in later studies. In the latest studies, a trend towards an increase in effect size was observed. In one of the datasets, a cumulative meta-analysis revealed publication bias against studies reporting disconfirming evidence; such studies were published in journals with a lower impact factor compared to studies with results supporting the hypothesis tested. Correlation analysis revealed neither temporal trends nor evidence of publication bias in the datasets analysed. We thus suggest that cumulative meta-analysis should be used as a visual aid to detect temporal trends and publication bias in research findings in ecology in addition to the correlative approach. PMID:15347521

  16. Glucose-6-phosphate dehydrogenase deficiency and the risk of malaria: A meta-analysis and trial sequential analysis

    NASA Astrophysics Data System (ADS)

    Sun, Fengmei; Zhang, Juan; Pu, Yuepu

    2017-10-01

    This study is designed to perform a meta-analysis and trial sequential analysis (TSA) to investigate whether people with G6PD deficiency suffered less malarial infection. We searched from PubMed, Science Direct, Springer Link, CNKI, and Wan Fang databases for case-control study, cohort study or cross section study until April 2017. TSA was used to determine the state of evidence and calculate the required sample size. Eight case-control studies and five cross-sectional studies (30,683participants) were included in this meta-analysis. Compared with normal control group, we found significant protection from severe malaria (OR 0.644, 95% CI [0.493-0.842]; P=0.001) among people with decreasing G6PD activity. People with variations of G6PD gene at nucleotide 202(G6PD A-) were also found to be associated with resistance on severe malaria pooled (OR 0.851, 95% CI [0.779-0.930]; P =0.0001). Sex-stratified test suggested that protection of severe malaria is conferred to both G6PD A-males and heterozygous females (with a single copy of the variant). In conclusion, our study found a significant protection from severe malaria among G6PD deficient people compared to the

  17. Neophyte experiences of football (soccer) match analysis: a multiple case study approach.

    PubMed

    McKenna, Mark; Cowan, Daryl Thomas; Stevenson, David; Baker, Julien Steven

    2018-03-05

    Performance analysis is extensively used in sport, but its pedagogical application is little understood. Given its expanding role across football, this study explored the experiences of neophyte performance analysts. Experiences of six analysis interns, across three professional football clubs, were investigated as multiple cases of new match analysis. Each intern was interviewed after their first season, with archival data providing background information. Four themes emerged from qualitative analysis: (1) "building of relationships" was important, along with trust and role clarity; (2) "establishing an analysis system" was difficult due to tacit coach knowledge, but analysis was established; (3) the quality of the "feedback process" hinged on coaching styles, with balance of feedback and athlete engagement considered essential; (4) "establishing effect" was complex with no statistical effects reported; yet enhanced relationships, role clarity, and improved performances were reported. Other emic accounts are required to further understand occupational culture within performance analysis.

  18. Application of multivariable statistical techniques in plant-wide WWTP control strategies analysis.

    PubMed

    Flores, X; Comas, J; Roda, I R; Jiménez, L; Gernaey, K V

    2007-01-01

    The main objective of this paper is to present the application of selected multivariable statistical techniques in plant-wide wastewater treatment plant (WWTP) control strategies analysis. In this study, cluster analysis (CA), principal component analysis/factor analysis (PCA/FA) and discriminant analysis (DA) are applied to the evaluation matrix data set obtained by simulation of several control strategies applied to the plant-wide IWA Benchmark Simulation Model No 2 (BSM2). These techniques allow i) to determine natural groups or clusters of control strategies with a similar behaviour, ii) to find and interpret hidden, complex and casual relation features in the data set and iii) to identify important discriminant variables within the groups found by the cluster analysis. This study illustrates the usefulness of multivariable statistical techniques for both analysis and interpretation of the complex multicriteria data sets and allows an improved use of information for effective evaluation of control strategies.

  19. Vehicle Design Evaluation Program (VDEP). A computer program for weight sizing, economic, performance and mission analysis of fuel-conservative aircraft, multibodied aircraft and large cargo aircraft using both JP and alternative fuels

    NASA Technical Reports Server (NTRS)

    Oman, B. H.

    1977-01-01

    The NASA Langley Research Center vehicle design evaluation program (VDEP-2) was expanded by (1) incorporating into the program a capability to conduct preliminary design studies on subsonic commercial transport type aircraft using both JP and such alternate fuels as hydrogen and methane;(2) incorporating an aircraft detailed mission and performance analysis capability; and (3) developing and incorporating an external loads analysis capability. The resulting computer program (VDEP-3) provides a preliminary design tool that enables the user to perform integrated sizing, structural analysis, and cost studies on subsonic commercial transport aircraft. Both versions of the VDEP-3 Program which are designated preliminary Analysis VDEP-3 and detailed Analysis VDEP utilize the same vehicle sizing subprogram which includes a detailed mission analysis capability, as well as a geometry and weight analysis for multibodied configurations.

  20. Content analysis and thematic analysis: Implications for conducting a qualitative descriptive study.

    PubMed

    Vaismoradi, Mojtaba; Turunen, Hannele; Bondas, Terese

    2013-09-01

    Qualitative content analysis and thematic analysis are two commonly used approaches in data analysis of nursing research, but boundaries between the two have not been clearly specified. In other words, they are being used interchangeably and it seems difficult for the researcher to choose between them. In this respect, this paper describes and discusses the boundaries between qualitative content analysis and thematic analysis and presents implications to improve the consistency between the purpose of related studies and the method of data analyses. This is a discussion paper, comprising an analytical overview and discussion of the definitions, aims, philosophical background, data gathering, and analysis of content analysis and thematic analysis, and addressing their methodological subtleties. It is concluded that in spite of many similarities between the approaches, including cutting across data and searching for patterns and themes, their main difference lies in the opportunity for quantification of data. It means that measuring the frequency of different categories and themes is possible in content analysis with caution as a proxy for significance. © 2013 Wiley Publishing Asia Pty Ltd.

  1. Mathematical Modelling Research in Turkey: A Content Analysis Study

    ERIC Educational Resources Information Center

    Çelik, H. Coskun

    2017-01-01

    The aim of the present study was to examine the mathematical modelling studies done between 2004 and 2015 in Turkey and to reveal their tendencies. Forty-nine studies were selected using purposeful sampling based on the term, "mathematical modelling" with Higher Education Academic Search Engine. They were analyzed with content analysis.…

  2. A Framework for Analysis of Case Studies of Reading Lessons

    ERIC Educational Resources Information Center

    Carlisle, Joanne F.; Kelcey, Ben; Rosaen, Cheryl; Phelps, Geoffrey; Vereb, Anita

    2013-01-01

    This paper focuses on the development and study of a framework to provide direction and guidance for practicing teachers in using a web-based case studies program for professional development in early reading; the program is called Case Studies Reading Lessons (CSRL). The framework directs and guides teachers' analysis of reading instruction by…

  3. Developing Teaching Skills through the School Practicum in Turkey: A Metasynthesis Study

    ERIC Educational Resources Information Center

    Tas, Mükerrem Akbulut; Karabay, Aysegül

    2016-01-01

    Using a metasynthesis approach, this study examined general teaching skills in previous studies on school practicum. The results and suggestions from 53 qualitative primary research studies that focused on school practicum in Turkey were reviewed. Data were collected using document analysis and content analysis using the NVivo10 programme. The…

  4. Using Meta-Analysis to Inform the Design of Subsequent Studies of Diagnostic Test Accuracy

    ERIC Educational Resources Information Center

    Hinchliffe, Sally R.; Crowther, Michael J.; Phillips, Robert S.; Sutton, Alex J.

    2013-01-01

    An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial…

  5. The practical application of adaptive study design in early phase clinical trials: a retrospective analysis of time savings.

    PubMed

    Lorch, U; Berelowitz, K; Ozen, C; Naseem, A; Akuffo, E; Taubel, J

    2012-05-01

    The interest in adaptive study design is evident from the growing amount of clinical research employing this model in the mid to later stages of medicines development. Little has been published on the practical application and merits of adaptive study design in early phase clinical research. This paper describes a retrospective analysis performed on a sample of 29 industry lead adaptive early phase studies commencing between 1 January 2006 and 31 December 2010 in a clinical trials unit in London, England. All studies containing at least one adaptive feature in the original protocol were included in the analysis. The scope of the analysis was to assess whether the use of adaptive study designs provided tangible benefits over the use of conventional study designs using time savings as the main measure. We conclude that the use of adaptive study design saves time in early phase research programs. This is achieved by abolishing the need for substantial amendments or by mitigating their impact on timelines and by using adaptive scheduling efficiencies.

  6. Text grouping in patent analysis using adaptive K-means clustering algorithm

    NASA Astrophysics Data System (ADS)

    Shanie, Tiara; Suprijadi, Jadi; Zulhanif

    2017-03-01

    Patents are one of the Intellectual Property. Analyzing patent is one requirement in knowing well the development of technology in each country and in the world now. This study uses the patent document coming from the Espacenet server about Green Tea. Patent documents related to the technology in the field of tea is still widespread, so it will be difficult for users to information retrieval (IR). Therefore, it is necessary efforts to categorize documents in a specific group of related terms contained therein. This study uses titles patent text data with the proposed Green Tea in Statistical Text Mining methods consists of two phases: data preparation and data analysis stage. The data preparation phase uses Text Mining methods and data analysis stage is done by statistics. Statistical analysis in this study using a cluster analysis algorithm, the Adaptive K-Means Clustering Algorithm. Results from this study showed that based on the maximum value Silhouette, generate 87 clusters associated fifteen terms therein that can be utilized in the process of information retrieval needs.

  7. Integrative Analysis of Cancer Diagnosis Studies with Composite Penalization

    PubMed Central

    Liu, Jin; Huang, Jian; Ma, Shuangge

    2013-01-01

    Summary In cancer diagnosis studies, high-throughput gene profiling has been extensively conducted, searching for genes whose expressions may serve as markers. Data generated from such studies have the “large d, small n” feature, with the number of genes profiled much larger than the sample size. Penalization has been extensively adopted for simultaneous estimation and marker selection. Because of small sample sizes, markers identified from the analysis of single datasets can be unsatisfactory. A cost-effective remedy is to conduct integrative analysis of multiple heterogeneous datasets. In this article, we investigate composite penalization methods for estimation and marker selection in integrative analysis. The proposed methods use the minimax concave penalty (MCP) as the outer penalty. Under the homogeneity model, the ridge penalty is adopted as the inner penalty. Under the heterogeneity model, the Lasso penalty and MCP are adopted as the inner penalty. Effective computational algorithms based on coordinate descent are developed. Numerical studies, including simulation and analysis of practical cancer datasets, show satisfactory performance of the proposed methods. PMID:24578589

  8. Computational Analysis of the Caenorhabditis elegans Germline to Study the Distribution of Nuclei, Proteins, and the Cytoskeleton.

    PubMed

    Gopal, Sandeep; Pocock, Roger

    2018-04-19

    The Caenorhabditis elegans (C. elegans) germline is used to study several biologically important processes including stem cell development, apoptosis, and chromosome dynamics. While the germline is an excellent model, the analysis is often two dimensional due to the time and labor required for three-dimensional analysis. Major readouts in such studies are the number/position of nuclei and protein distribution within the germline. Here, we present a method to perform automated analysis of the germline using confocal microscopy and computational approaches to determine the number and position of nuclei in each region of the germline. Our method also analyzes germline protein distribution that enables the three-dimensional examination of protein expression in different genetic backgrounds. Further, our study shows variations in cytoskeletal architecture in distinct regions of the germline that may accommodate specific spatial developmental requirements. Finally, our method enables automated counting of the sperm in the spermatheca of each germline. Taken together, our method enables rapid and reproducible phenotypic analysis of the C. elegans germline.

  9. Economic analysis of the health impacts of housing improvement studies: a systematic review

    PubMed Central

    Fenwick, Elisabeth; Macdonald, Catriona; Thomson, Hilary

    2013-01-01

    Background Economic evaluation of public policies has been advocated but rarely performed. Studies from a systematic review of the health impacts of housing improvement included data on costs and some economic analysis. Examination of these data provides an opportunity to explore the difficulties and the potential for economic evaluation of housing. Methods Data were extracted from all studies included in the systematic review of housing improvement which had reported costs and economic analysis (n=29/45). The reported data were assessed for their suitability to economic evaluation. Where an economic analysis was reported the analysis was described according to pre-set definitions of various types of economic analysis used in the field of health economics. Results 25 studies reported cost data on the intervention and/or benefits to the recipients. Of these, 11 studies reported data which was considered amenable to economic evaluation. A further four studies reported conducting an economic evaluation. Three of these studies presented a hybrid ‘balance sheet’ approach and indicated a net economic benefit associated with the intervention. One cost-effectiveness evaluation was identified but the data were unclearly reported; the cost-effectiveness plane suggested that the intervention was more costly and less effective than the status quo. Conclusions Future studies planning an economic evaluation need to (i) make best use of available data and (ii) ensure that all relevant data are collected. To facilitate this, economic evaluations should be planned alongside the intervention with input from health economists from the outset of the study. When undertaken appropriately, economic evaluation provides the potential to make significant contributions to housing policy. PMID:23929616

  10. Predictors of Shunt-dependent Hydrocephalus After Aneurysmal Subarachnoid Hemorrhage? A Systematic Review and Meta-Analysis.

    PubMed

    Xie, Zhiyi; Hu, Xin; Zan, Xin; Lin, Sen; Li, Hao; You, Chao

    2017-10-01

    Hydrocephalus is a well-recognized complication after aneurysmal subarachnoid hemorrhage (aSAH). This study aimed to identify predictors for shunt-dependent hydrocephalus (SDHC) after aSAH via a systematic review and meta-analysis. A systematic search was conducted using the Embase, MEDLINE, and Web of Science databases for studies pertaining to aSAH and SDHC. Risk factors were assessed by meta-analysis when they were reported by at least 2 studies. The results were presented as odd ratios or risk ratios according to the study design with the corresponding 95% confidence intervals (CI). Twenty-five studies were included. In primary analysis of 14 potential risk factors, 12 were identified as predictors of SDHC after aSAH including age ≥50 years, female gender, high Hunt-Hess grade, Glasgow Coma Scale ≤8, Fisher grade ≥3, acute hydrocephalus, external ventricular drainage insertion, intraventricular hemorrhage, postcirculation aneurysm, anterior communicating artery aneurysm, meningitis, and rebleeding. The meta-analysis based on cohort studies found a significantly increased risk for SDHC in patients with aSAH treated by coiling (risk ratio, 1.16; 95% CI, 1.05-1.29), while the meta-analysis based on case-controlled studies failed to replicate this finding (odds ratio, 1.27; 95% CI, 0.95-1.71). Several new predictors of SDHC after aSAH were identified that may assist with the early recognition and prevention of SDHC. The controversial evidence found in this study was insufficient to support the potential of neurosurgical clipping for reducing the risk of shunt dependency. Further well-designed studies are warranted to explore the effect of treatment modality on SDHC risk. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Analytical study of comet nucleus samples

    NASA Technical Reports Server (NTRS)

    Albee, A. L.

    1989-01-01

    Analytical procedures for studying and handling frozen (130 K) core samples of comet nuclei are discussed. These methods include neutron activation analysis, x ray fluorescent analysis and high resolution mass spectroscopy.

  12. Reporting quality of statistical methods in surgical observational studies: protocol for systematic review.

    PubMed

    Wu, Robert; Glen, Peter; Ramsay, Tim; Martel, Guillaume

    2014-06-28

    Observational studies dominate the surgical literature. Statistical adjustment is an important strategy to account for confounders in observational studies. Research has shown that published articles are often poor in statistical quality, which may jeopardize their conclusions. The Statistical Analyses and Methods in the Published Literature (SAMPL) guidelines have been published to help establish standards for statistical reporting.This study will seek to determine whether the quality of statistical adjustment and the reporting of these methods are adequate in surgical observational studies. We hypothesize that incomplete reporting will be found in all surgical observational studies, and that the quality and reporting of these methods will be of lower quality in surgical journals when compared with medical journals. Finally, this work will seek to identify predictors of high-quality reporting. This work will examine the top five general surgical and medical journals, based on a 5-year impact factor (2007-2012). All observational studies investigating an intervention related to an essential component area of general surgery (defined by the American Board of Surgery), with an exposure, outcome, and comparator, will be included in this systematic review. Essential elements related to statistical reporting and quality were extracted from the SAMPL guidelines and include domains such as intent of analysis, primary analysis, multiple comparisons, numbers and descriptive statistics, association and correlation analyses, linear regression, logistic regression, Cox proportional hazard analysis, analysis of variance, survival analysis, propensity analysis, and independent and correlated analyses. Each article will be scored as a proportion based on fulfilling criteria in relevant analyses used in the study. A logistic regression model will be built to identify variables associated with high-quality reporting. A comparison will be made between the scores of surgical observational studies published in medical versus surgical journals. Secondary outcomes will pertain to individual domains of analysis. Sensitivity analyses will be conducted. This study will explore the reporting and quality of statistical analyses in surgical observational studies published in the most referenced surgical and medical journals in 2013 and examine whether variables (including the type of journal) can predict high-quality reporting.

  13. Space tug economic analysis study. Volume 2: Tug concepts analysis. Part 2: Economic analysis

    NASA Technical Reports Server (NTRS)

    1972-01-01

    An economic analysis of space tug operations is presented. The subjects discussed are: (1) cost uncertainties, (2) scenario analysis, (3) economic sensitivities, (4) mixed integer programming formulation of the space tug problem, and (5) critical parameters in the evaluation of a public expenditure.

  14. Periodontal disease and carotid atherosclerosis: A meta-analysis of 17,330 participants.

    PubMed

    Zeng, Xian-Tao; Leng, Wei-Dong; Lam, Yat-Yin; Yan, Bryan P; Wei, Xue-Mei; Weng, Hong; Kwong, Joey S W

    2016-01-15

    The association between periodontal disease and carotid atherosclerosis has been evaluated primarily in single-center studies, and whether periodontal disease is an independent risk factor of carotid atherosclerosis remains uncertain. This meta-analysis aimed to evaluate the association between periodontal disease and carotid atherosclerosis. We searched PubMed and Embase for relevant observational studies up to February 20, 2015. Two authors independently extracted data from included studies, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for overall and subgroup meta-analyses. Statistical heterogeneity was assessed by the chi-squared test (P<0.1 for statistical significance) and quantified by the I(2) statistic. Data analysis was conducted using the Comprehensive Meta-Analysis (CMA) software. Fifteen observational studies involving 17,330 participants were included in the meta-analysis. The overall pooled result showed that periodontal disease was associated with carotid atherosclerosis (OR: 1.27, 95% CI: 1.14-1.41; P<0.001) but statistical heterogeneity was substantial (I(2)=78.90%). Subgroup analysis of adjusted smoking and diabetes mellitus showed borderline significance (OR: 1.08; 95% CI: 1.00-1.18; P=0.05). Sensitivity and cumulative analyses both indicated that our results were robust. Findings of our meta-analysis indicated that the presence of periodontal disease was associated with carotid atherosclerosis; however, further large-scale, well-conducted clinical studies are needed to explore the precise risk of developing carotid atherosclerosis in patients with periodontal disease. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Cardiopulmonary resuscitation quality: Widespread variation in data intervals used for analysis.

    PubMed

    Talikowska, Milena; Tohira, Hideo; Bailey, Paul; Finn, Judith

    2016-05-01

    There is a growing body of evidence for the relationship between CPR quality and survival in cardiac arrest patients. We sought to describe the characteristics of the analysis intervals used across studies. Relevant papers were selected as described in our recent systematic review. From these papers we collected information about (1) the time interval used for analysis; (2) the event that marked the beginning of the analysis interval; and (3) the minimum amount of CPR quality data required for a case to be included in the analysed cohort. We then compared this data across papers. Twenty-one studies reported on the association between CPR quality and cardiac arrest patient survival. In two thirds of studies data from the start of the resuscitation episode was analysed, in particular the first 5min. Commencement of the analysis interval was marked by various events including ECG pad placement and first chest compression. Nine studies specified a minimum amount of data that had to have been collected for the individual case to be included in the analysis; most commonly 1min of data. The use of shorter intervals allowed for inclusion of more cases as it included cases that did not have a complete dataset. To facilitate comparisons across studies, a standardised definition of the data analysis interval should be developed; one that maximises the amount of cases available without compromising the data's representability of the resuscitation effort. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Genome-Wide Identification and Evaluation of Reference Genes for Quantitative RT-PCR Analysis during Tomato Fruit Development.

    PubMed

    Cheng, Yuan; Bian, Wuying; Pang, Xin; Yu, Jiahong; Ahammed, Golam J; Zhou, Guozhi; Wang, Rongqing; Ruan, Meiying; Li, Zhimiao; Ye, Qingjing; Yao, Zhuping; Yang, Yuejian; Wan, Hongjian

    2017-01-01

    Gene expression analysis in tomato fruit has drawn increasing attention nowadays. Quantitative real-time PCR (qPCR) is a routine technique for gene expression analysis. In qPCR operation, reliability of results largely depends on the choice of appropriate reference genes (RGs). Although tomato is a model for fruit biology study, few RGs for qPCR analysis in tomato fruit had yet been developed. In this study, we initially identified 38 most stably expressed genes based on tomato transcriptome data set, and their expression stabilities were further determined in a set of tomato fruit samples of four different fruit developmental stages (Immature, mature green, breaker, mature red) using qPCR analysis. Two statistical algorithms, geNorm and Normfinder, concordantly determined the superiority of these identified putative RGs. Notably, SlFRG05 (Solyc01g104170), SlFRG12 (Solyc04g009770), SlFRG16 (Solyc10g081190), SlFRG27 (Solyc06g007510), and SlFRG37 (Solyc11g005330) were proved to be suitable RGs for tomato fruit development study. Further analysis using geNorm indicate that the combined use of SlFRG03 (Solyc02g063070) and SlFRG27 would provide more reliable normalization results in qPCR experiments. The identified RGs in this study will be beneficial for future qPCR analysis of tomato fruit developmental study, as well as for the potential identification of optimal normalization controls in other plant species.

  17. Genome-Wide Identification and Evaluation of Reference Genes for Quantitative RT-PCR Analysis during Tomato Fruit Development

    PubMed Central

    Cheng, Yuan; Bian, Wuying; Pang, Xin; Yu, Jiahong; Ahammed, Golam J.; Zhou, Guozhi; Wang, Rongqing; Ruan, Meiying; Li, Zhimiao; Ye, Qingjing; Yao, Zhuping; Yang, Yuejian; Wan, Hongjian

    2017-01-01

    Gene expression analysis in tomato fruit has drawn increasing attention nowadays. Quantitative real-time PCR (qPCR) is a routine technique for gene expression analysis. In qPCR operation, reliability of results largely depends on the choice of appropriate reference genes (RGs). Although tomato is a model for fruit biology study, few RGs for qPCR analysis in tomato fruit had yet been developed. In this study, we initially identified 38 most stably expressed genes based on tomato transcriptome data set, and their expression stabilities were further determined in a set of tomato fruit samples of four different fruit developmental stages (Immature, mature green, breaker, mature red) using qPCR analysis. Two statistical algorithms, geNorm and Normfinder, concordantly determined the superiority of these identified putative RGs. Notably, SlFRG05 (Solyc01g104170), SlFRG12 (Solyc04g009770), SlFRG16 (Solyc10g081190), SlFRG27 (Solyc06g007510), and SlFRG37 (Solyc11g005330) were proved to be suitable RGs for tomato fruit development study. Further analysis using geNorm indicate that the combined use of SlFRG03 (Solyc02g063070) and SlFRG27 would provide more reliable normalization results in qPCR experiments. The identified RGs in this study will be beneficial for future qPCR analysis of tomato fruit developmental study, as well as for the potential identification of optimal normalization controls in other plant species. PMID:28900431

  18. Association between metabolic syndrome and bone fractures: a meta-analysis of observational studies.

    PubMed

    Sun, Kan; Liu, Jianmin; Lu, Nan; Sun, Hanxiao; Ning, Guang

    2014-02-09

    Emerging epidemiological evidence suggest an association between metabolic syndrome and fractures. However, whether metabolic syndrome is an independent risk or protective factor of fractures remains controversial. Our goal is to provide a quantitative assessment of the association between metabolic syndrome and bone fractures by conducting a meta-analysis of observational studies. The PubMed and Embase database were searched through to March 2013 to identify studies that met pre-established inclusion criteria. Reference lists of retrieved articles were also reviewed. Summary effect estimates with 95% confidence intervals (CI) were derived using a fixed or random effects model, depending on the heterogeneity of the included studies. Eight epidemiologic studies involving 39,938 participants were included in the meta-analysis. In overall analysis, metabolic syndrome was not associated with prevalent fractures [pooled odds ratio (OR) 0.93, 95% CI 0.84 - 1.03] in cross-sectional studies or incident fractures [pooled relative risk (RR) 0.88, 95% CI 0.37 - 2.12] in prospective cohort studies. No evidence of heterogeneity was found in cross-sectional studies (p = 0.786, I2 = 0.0%). A substantial heterogeneity was detected in cohort studies (p = 0.001, I2 = 85.7%). No indication of significant publication bias was found either from Begg's test or Egger's test. Estimates of total effects were substantially consistent in the sensitivity and stratification analyses. The present meta-analysis of observational studies suggests that the metabolic syndrome has no explicit effect on bone fractures.

  19. Vitamin D and Depression: A Systematic Review and Meta-Analysis Comparing Studies with and without Biological Flaws

    PubMed Central

    Spedding, Simon

    2014-01-01

    Efficacy of Vitamin D supplements in depression is controversial, awaiting further literature analysis. Biological flaws in primary studies is a possible reason meta-analyses of Vitamin D have failed to demonstrate efficacy. This systematic review and meta-analysis of Vitamin D and depression compared studies with and without biological flaws. The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The literature search was undertaken through four databases for randomized controlled trials (RCTs). Studies were critically appraised for methodological quality and biological flaws, in relation to the hypothesis and study design. Meta-analyses were performed for studies according to the presence of biological flaws. The 15 RCTs identified provide a more comprehensive evidence-base than previous systematic reviews; methodological quality of studies was generally good and methodology was diverse. A meta-analysis of all studies without flaws demonstrated a statistically significant improvement in depression with Vitamin D supplements (+0.78 CI +0.24, +1.27). Studies with biological flaws were mainly inconclusive, with the meta-analysis demonstrating a statistically significant worsening in depression by taking Vitamin D supplements (−1.1 CI −0.7, −1.5). Vitamin D supplementation (≥800 I.U. daily) was somewhat favorable in the management of depression in studies that demonstrate a change in vitamin levels, and the effect size was comparable to that of anti-depressant medication. PMID:24732019

  20. The impact of response measurement error on the analysis of designed experiments

    DOE PAGES

    Anderson-Cook, Christine Michaela; Hamada, Michael Scott; Burr, Thomas Lee

    2016-11-01

    This study considers the analysis of designed experiments when there is measurement error in the true response or so-called response measurement error. We consider both additive and multiplicative response measurement errors. Through a simulation study, we investigate the impact of ignoring the response measurement error in the analysis, that is, by using a standard analysis based on t-tests. In addition, we examine the role of repeat measurements in improving the quality of estimation and prediction in the presence of response measurement error. We also study a Bayesian approach that accounts for the response measurement error directly through the specification ofmore » the model, and allows including additional information about variability in the analysis. We consider the impact on power, prediction, and optimization. Copyright © 2015 John Wiley & Sons, Ltd.« less

  1. The impact of response measurement error on the analysis of designed experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson-Cook, Christine Michaela; Hamada, Michael Scott; Burr, Thomas Lee

    This study considers the analysis of designed experiments when there is measurement error in the true response or so-called response measurement error. We consider both additive and multiplicative response measurement errors. Through a simulation study, we investigate the impact of ignoring the response measurement error in the analysis, that is, by using a standard analysis based on t-tests. In addition, we examine the role of repeat measurements in improving the quality of estimation and prediction in the presence of response measurement error. We also study a Bayesian approach that accounts for the response measurement error directly through the specification ofmore » the model, and allows including additional information about variability in the analysis. We consider the impact on power, prediction, and optimization. Copyright © 2015 John Wiley & Sons, Ltd.« less

  2. Parametric and experimental analysis using a power flow approach

    NASA Technical Reports Server (NTRS)

    Cuschieri, J. M.

    1990-01-01

    A structural power flow approach for the analysis of structure-borne transmission of vibrations is used to analyze the influence of structural parameters on transmitted power. The parametric analysis is also performed using the Statistical Energy Analysis approach and the results are compared with those obtained using the power flow approach. The advantages of structural power flow analysis are demonstrated by comparing the type of results that are obtained by the two analytical methods. Also, to demonstrate that the power flow results represent a direct physical parameter that can be measured on a typical structure, an experimental study of structural power flow is presented. This experimental study presents results for an L shaped beam for which an available solution was already obtained. Various methods to measure vibrational power flow are compared to study their advantages and disadvantages.

  3. Shuttle Ground Operations Efficiencies/Technologies (SGOE/T) study. Volume 2: Ground Operations evaluation

    NASA Technical Reports Server (NTRS)

    Scholz, A. L.; Hart, M. T.; Lowry, D. J.

    1987-01-01

    The Ground Operations Evaluation describes the breath and depth of the various study elements selected as a result of an operational analysis conducted during the early part of the study. Analysis techniques used for the evaluation are described in detail. Elements selected for further evaluation are identified; the results of the analysis documented; and a follow-on course of action recommended. The background and rationale for developing recommendations for the current Shuttle or for future programs is presented.

  4. Real Options in Defense R and D: A Decision Tree Analysis Approach for Options to Defer, Abandon, and Expand

    DTIC Science & Technology

    2016-12-01

    chosen rather than complex ones , and responds to the criticism of the DTA approach. Chapter IV provides three separate case studies in defense R&D...defense R&D projects. To this end, the first section describes the case study method and the advantages of using simple models over more complex ones ...the analysis lacked empirical data and relied on subjective data, the analysis successfully combined the DTA approach with the case study method and

  5. Space shuttle navigation analysis

    NASA Technical Reports Server (NTRS)

    Jones, H. L.; Luders, G.; Matchett, G. A.; Sciabarrasi, J. E.

    1976-01-01

    A detailed analysis of space shuttle navigation for each of the major mission phases is presented. A covariance analysis program for prelaunch IMU calibration and alignment for the orbital flight tests (OFT) is described, and a partial error budget is presented. The ascent, orbital operations and deorbit maneuver study considered GPS-aided inertial navigation in the Phase III GPS (1984+) time frame. The entry and landing study evaluated navigation performance for the OFT baseline system. Detailed error budgets and sensitivity analyses are provided for both the ascent and entry studies.

  6. Some studies on the use of NASTRAN for nuclear power plant structural analysis and design

    NASA Technical Reports Server (NTRS)

    Setlur, A. V.; Valathur, M.

    1973-01-01

    Studies made on the use of NASTRAN for nuclear power plant analysis and design are presented. These studies indicate that NASTRAN could be effectively used for static, dynamic and special purpose problems encountered in the design of such plants. Normal mode capability of NASTRAN is extended through a post-processor program to handle seismic analysis. Static and dynamic substructuring is discussed. Extension of NASTRAN to include the needs in the civil engineering industry is discussed.

  7. Sex Estimation From Sternal Measurements Using Multidetector Computed Tomography

    PubMed Central

    Ekizoglu, Oguzhan; Hocaoglu, Elif; Inci, Ercan; Bilgili, Mustafa Gokhan; Solmaz, Dilek; Erdil, Irem; Can, Ismail Ozgur

    2014-01-01

    Abstract We aimed to show the utility and reliability of sternal morphometric analysis for sex estimation. Sex estimation is a very important step in forensic identification. Skeletal surveys are main methods for sex estimation studies. Morphometric analysis of sternum may provide high accuracy rated data in sex discrimination. In this study, morphometric analysis of sternum was evaluated in 1 mm chest computed tomography scans for sex estimation. Four hundred forty 3 subjects (202 female, 241 male, mean age: 44 ± 8.1 [distribution: 30–60 year old]) were included the study. Manubrium length (ML), mesosternum length (2L), Sternebra 1 (S1W), and Sternebra 3 (S3W) width were measured and also sternal index (SI) was calculated. Differences between genders were evaluated by student t-test. Predictive factors of sex were determined by discrimination analysis and receiver operating characteristic (ROC) analysis. Male sternal measurement values are significantly higher than females (P < 0.001) while SI is significantly low in males (P < 0.001). In discrimination analysis, MSL has high accuracy rate with 80.2% in females and 80.9% in males. MSL also has the best sensitivity (75.9%) and specificity (87.6%) values. Accuracy rates were above 80% in 3 stepwise discrimination analysis for both sexes. Stepwise 1 (ML, MSL, S1W, S3W) has the highest accuracy rate in stepwise discrimination analysis with 86.1% in females and 83.8% in males. Our study showed that morphometric computed tomography analysis of sternum might provide important information for sex estimation. PMID:25501090

  8. A Content Analysis of the WH-Questions in the EFL Textbook of "Horizons"

    ERIC Educational Resources Information Center

    Igbaria, Abdul Kareem

    2013-01-01

    This study dealt with analysis of the study units in the textbook "Horizons" for 9th-grade students studying English in mixed ability classes. The study sought to examine the variety in the cognitive level represented by the WH-questions in the textbook according to Bloom's taxonomy. The study also attempted to examine the extent in…

  9. Validity analysis on merged and averaged data using within and between analysis: focus on effect of qualitative social capital on self-rated health.

    PubMed

    Shin, Sang Soo; Shin, Young-Jeon

    2016-01-01

    With an increasing number of studies highlighting regional social capital (SC) as a determinant of health, many studies are using multi-level analysis with merged and averaged scores of community residents' survey responses calculated from community SC data. Sufficient examination is required to validate if the merged and averaged data can represent the community. Therefore, this study analyzes the validity of the selected indicators and their applicability in multi-level analysis. Within and between analysis (WABA) was performed after creating community variables using merged and averaged data of community residents' responses from the 2013 Community Health Survey in Korea, using subjective self-rated health assessment as a dependent variable. Further analysis was performed following the model suggested by WABA result. Both E-test results (1) and WABA results (2) revealed that single-level analysis needs to be performed using qualitative SC variable with cluster mean centering. Through single-level multivariate regression analysis, qualitative SC with cluster mean centering showed positive effect on self-rated health (0.054, p<0.001), although there was no substantial difference in comparison to analysis using SC variables without cluster mean centering or multi-level analysis. As modification in qualitative SC was larger within the community than between communities, we validate that relational analysis of individual self-rated health can be performed within the group, using cluster mean centering. Other tests besides the WABA can be performed in the future to confirm the validity of using community variables and their applicability in multi-level analysis.

  10. The Woodlands Metro Center energy study. Case studies of project planning and design for energy conservation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1980-03-01

    Appendix II of The Woodlands Metro Center Energy Study near Houston consists of the following: Metro Center Program, Conventional Plan Building Prototypes and Detail Parcel Analysis, Energy Plan Building Prototypes, and Energy Plan Detail Parcel Analysis.

  11. NHEXAS PHASE I MARYLAND STUDY--LIST OF AVAILABLE DOCUMENTS: PROTOCOLS AND SOPS

    EPA Science Inventory

    This document lists available protocols and SOPs for the NHEXAS Phase I Maryland study. It identifies protocols and SOPs for the following study components: (1) Sample collection and field operations, (2) Sample analysis and general laboratory procedures, (3) Data Analysis Proced...

  12. Use of LEED, Auger emission spectroscopy and field ion microscopy in microstructural studies

    NASA Technical Reports Server (NTRS)

    Ferrante, J.; Buckley, D. H.; Pepper, S. V.; Brainard, W. A.

    1972-01-01

    Surface research tools such as LEED, Auger emission spectroscopy analysis, and field ion microscopy are discussed. Examples of their use in studying adhesion, friction, wear, and lubrication presented. These tools have provided considerable insight into the basic nature of solid surface interactions. The transfer of metals from one surface to another at the atomic level has been observed and studied with each of these devices. The field ion microscope has been used to study polymer-metal interactions and Auger analysis to study the mechanism of polymer adhesion to metals. LEED and Auger analysis have identified surface segregation of alloying elements and indicated the influence of these elements in metallic adhesion. LEED and Auger analysis have assisted in adsorption studies in determining the structural arrangement and quantity of adsorbed species present in making an understanding of the influence of these species on adhesion possible. These devices are assisting in the furtherance of understanding of the fundamental mechanism involved in the adhesion, friction, wear, and lubrication processes.

  13. A Study of ATLAS Grid Performance for Distributed Analysis

    NASA Astrophysics Data System (ADS)

    Panitkin, Sergey; Fine, Valery; Wenaus, Torre

    2012-12-01

    In the past two years the ATLAS Collaboration at the LHC has collected a large volume of data and published a number of ground breaking papers. The Grid-based ATLAS distributed computing infrastructure played a crucial role in enabling timely analysis of the data. We will present a study of the performance and usage of the ATLAS Grid as platform for physics analysis in 2011. This includes studies of general properties as well as timing properties of user jobs (wait time, run time, etc). These studies are based on mining of data archived by the PanDA workload management system.

  14. Four applications of a software data collection and analysis methodology

    NASA Technical Reports Server (NTRS)

    Basili, Victor R.; Selby, Richard W., Jr.

    1985-01-01

    The evaluation of software technologies suffers because of the lack of quantitative assessment of their effect on software development and modification. A seven-step data collection and analysis methodology couples software technology evaluation with software measurement. Four in-depth applications of the methodology are presented. The four studies represent each of the general categories of analyses on the software product and development process: blocked subject-project studies, replicated project studies, multi-project variation studies, and single project strategies. The four applications are in the areas of, respectively, software testing, cleanroom software development, characteristic software metric sets, and software error analysis.

  15. Analysis of airframe/engine interactions in integrated flight and propulsion control

    NASA Technical Reports Server (NTRS)

    Schierman, John D.; Schmidt, David K.

    1991-01-01

    An analysis framework for the assessment of dynamic cross-coupling between airframe and engine systems from the perspective of integrated flight/propulsion control is presented. This analysis involves to determining the significance of the interactions with respect to deterioration in stability robustness and performance, as well as critical frequency ranges where problems may occur due to these interactions. The analysis illustrated here investigates both the airframe's effects on the engine control loops and the engine's effects on the airframe control loops in two case studies. The second case study involves a multi-input/multi-output analysis of the airframe. Sensitivity studies are performed on critical interactions to examine the degradations in the system's stability robustness and performance. Magnitudes of the interactions required to cause instabilities, as well as the frequencies at which the instabilities occur are recorded. Finally, the analysis framework is expanded to include control laws which contain cross-feeds between the airframe and engine systems.

  16. 34 CFR 477.4 - What regulations apply?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., DEPARTMENT OF EDUCATION STATE PROGRAM ANALYSIS ASSISTANCE AND POLICY STUDIES PROGRAM General § 477.4 What regulations apply? The following regulations apply to the State Program Analysis Assistance and Policy Studies...

  17. 34 CFR 477.4 - What regulations apply?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., DEPARTMENT OF EDUCATION STATE PROGRAM ANALYSIS ASSISTANCE AND POLICY STUDIES PROGRAM General § 477.4 What regulations apply? The following regulations apply to the State Program Analysis Assistance and Policy Studies...

  18. An improved method for bivariate meta-analysis when within-study correlations are unknown.

    PubMed

    Hong, Chuan; D Riley, Richard; Chen, Yong

    2018-03-01

    Multivariate meta-analysis, which jointly analyzes multiple and possibly correlated outcomes in a single analysis, is becoming increasingly popular in recent years. An attractive feature of the multivariate meta-analysis is its ability to account for the dependence between multiple estimates from the same study. However, standard inference procedures for multivariate meta-analysis require the knowledge of within-study correlations, which are usually unavailable. This limits standard inference approaches in practice. Riley et al proposed a working model and an overall synthesis correlation parameter to account for the marginal correlation between outcomes, where the only data needed are those required for a separate univariate random-effects meta-analysis. As within-study correlations are not required, the Riley method is applicable to a wide variety of evidence synthesis situations. However, the standard variance estimator of the Riley method is not entirely correct under many important settings. As a consequence, the coverage of a function of pooled estimates may not reach the nominal level even when the number of studies in the multivariate meta-analysis is large. In this paper, we improve the Riley method by proposing a robust variance estimator, which is asymptotically correct even when the model is misspecified (ie, when the likelihood function is incorrect). Simulation studies of a bivariate meta-analysis, in a variety of settings, show a function of pooled estimates has improved performance when using the proposed robust variance estimator. In terms of individual pooled estimates themselves, the standard variance estimator and robust variance estimator give similar results to the original method, with appropriate coverage. The proposed robust variance estimator performs well when the number of studies is relatively large. Therefore, we recommend the use of the robust method for meta-analyses with a relatively large number of studies (eg, m≥50). When the sample size is relatively small, we recommend the use of the robust method under the working independence assumption. We illustrate the proposed method through 2 meta-analyses. Copyright © 2017 John Wiley & Sons, Ltd.

  19. Meta-analysis of the association between short-term exposure to ambient ozone and respiratory hospital admissions

    NASA Astrophysics Data System (ADS)

    Ji, Meng; Cohan, Daniel S.; Bell, Michelle L.

    2011-04-01

    Ozone is associated with health impacts including respiratory outcomes; however, results differ across studies. Meta-analysis is an increasingly important approach to synthesizing evidence across studies. We conducted meta-analysis of short-term ozone exposure and respiratory hospitalizations to evaluate variation across studies and explore some of the challenges in meta-analysis. We identified 136 estimates from 96 studies and investigated how estimates differed by age, ozone metric, season, lag, region, disease category, and hospitalization type. Overall results indicate associations between ozone and various kinds of respiratory hospitalizations; however, study characteristics affected risk estimates. Estimates were similar, but higher, for the elderly compared to all ages and for previous day exposure compared to same day exposure. Comparison across studies was hindered by variation in definitions of disease categories, as some (e.g., asthma) were identified through >= 3 different sets of ICD codes. Although not all analyses exhibited evidence of publication bias, adjustment for publication bias generally lowered overall estimates. Emergency hospitalizations for total respiratory disease increased by 4.47% (95% interval: 2.48, 6.50%) per 10 ppb 24 h ozone among the elderly without adjustment for publication bias and 2.97% (1.05, 4.94%) with adjustment. Comparison of multi-city study results and meta-analysis based on single-city studies further suggested publication bias.

  20. Use of direct gradient analysis to uncover biological hypotheses in 16s survey data and beyond.

    PubMed

    Erb-Downward, John R; Sadighi Akha, Amir A; Wang, Juan; Shen, Ning; He, Bei; Martinez, Fernando J; Gyetko, Margaret R; Curtis, Jeffrey L; Huffnagle, Gary B

    2012-01-01

    This study investigated the use of direct gradient analysis of bacterial 16S pyrosequencing surveys to identify relevant bacterial community signals in the midst of a "noisy" background, and to facilitate hypothesis-testing both within and beyond the realm of ecological surveys. The results, utilizing 3 different real world data sets, demonstrate the utility of adding direct gradient analysis to any analysis that draws conclusions from indirect methods such as Principal Component Analysis (PCA) and Principal Coordinates Analysis (PCoA). Direct gradient analysis produces testable models, and can identify significant patterns in the midst of noisy data. Additionally, we demonstrate that direct gradient analysis can be used with other kinds of multivariate data sets, such as flow cytometric data, to identify differentially expressed populations. The results of this study demonstrate the utility of direct gradient analysis in microbial ecology and in other areas of research where large multivariate data sets are involved.

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