Sample records for randomized experimental study

  1. Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship – Quasi-Experimental Designs

    PubMed Central

    Schweizer, Marin L.; Braun, Barbara I.; Milstone, Aaron M.

    2016-01-01

    Quasi-experimental studies evaluate the association between an intervention and an outcome using experiments in which the intervention is not randomly assigned. Quasi-experimental studies are often used to evaluate rapid responses to outbreaks or other patient safety problems requiring prompt non-randomized interventions. Quasi-experimental studies can be categorized into three major types: interrupted time series designs, designs with control groups, and designs without control groups. This methods paper highlights key considerations for quasi-experimental studies in healthcare epidemiology and antimicrobial stewardship including study design and analytic approaches to avoid selection bias and other common pitfalls of quasi-experimental studies. PMID:27267457

  2. Time-varying output performances of piezoelectric vibration energy harvesting under nonstationary random vibrations

    NASA Astrophysics Data System (ADS)

    Yoon, Heonjun; Kim, Miso; Park, Choon-Su; Youn, Byeng D.

    2018-01-01

    Piezoelectric vibration energy harvesting (PVEH) has received much attention as a potential solution that could ultimately realize self-powered wireless sensor networks. Since most ambient vibrations in nature are inherently random and nonstationary, the output performances of PVEH devices also randomly change with time. However, little attention has been paid to investigating the randomly time-varying electroelastic behaviors of PVEH systems both analytically and experimentally. The objective of this study is thus to make a step forward towards a deep understanding of the time-varying performances of PVEH devices under nonstationary random vibrations. Two typical cases of nonstationary random vibration signals are considered: (1) randomly-varying amplitude (amplitude modulation; AM) and (2) randomly-varying amplitude with randomly-varying instantaneous frequency (amplitude and frequency modulation; AM-FM). In both cases, this study pursues well-balanced correlations of analytical predictions and experimental observations to deduce the relationships between the time-varying output performances of the PVEH device and two primary input parameters, such as a central frequency and an external electrical resistance. We introduce three correlation metrics to quantitatively compare analytical prediction and experimental observation, including the normalized root mean square error, the correlation coefficient, and the weighted integrated factor. Analytical predictions are in an excellent agreement with experimental observations both mechanically and electrically. This study provides insightful guidelines for designing PVEH devices to reliably generate electric power under nonstationary random vibrations.

  3. Study Design Rigor in Animal-Experimental Research Published in Anesthesia Journals.

    PubMed

    Hoerauf, Janine M; Moss, Angela F; Fernandez-Bustamante, Ana; Bartels, Karsten

    2018-01-01

    Lack of reproducibility of preclinical studies has been identified as an impediment for translation of basic mechanistic research into effective clinical therapies. Indeed, the National Institutes of Health has revised its grant application process to require more rigorous study design, including sample size calculations, blinding procedures, and randomization steps. We hypothesized that the reporting of such metrics of study design rigor has increased over time for animal-experimental research published in anesthesia journals. PubMed was searched for animal-experimental studies published in 2005, 2010, and 2015 in primarily English-language anesthesia journals. A total of 1466 publications were graded on the performance of sample size estimation, randomization, and blinding. Cochran-Armitage test was used to assess linear trends over time for the primary outcome of whether or not a metric was reported. Interrater agreement for each of the 3 metrics (power, randomization, and blinding) was assessed using the weighted κ coefficient in a 10% random sample of articles rerated by a second investigator blinded to the ratings of the first investigator. A total of 1466 manuscripts were analyzed. Reporting for all 3 metrics of experimental design rigor increased over time (2005 to 2010 to 2015): for power analysis, from 5% (27/516), to 12% (59/485), to 17% (77/465); for randomization, from 41% (213/516), to 50% (243/485), to 54% (253/465); and for blinding, from 26% (135/516), to 38% (186/485), to 47% (217/465). The weighted κ coefficients and 98.3% confidence interval indicate almost perfect agreement between the 2 raters beyond that which occurs by chance alone (power, 0.93 [0.85, 1.0], randomization, 0.91 [0.85, 0.98], and blinding, 0.90 [0.84, 0.96]). Our hypothesis that reported metrics of rigor in animal-experimental studies in anesthesia journals have increased during the past decade was confirmed. More consistent reporting, or explicit justification for absence, of sample size calculations, blinding techniques, and randomization procedures could better enable readers to evaluate potential sources of bias in animal-experimental research manuscripts. Future studies should assess whether such steps lead to improved translation of animal-experimental anesthesia research into successful clinical trials.

  4. A Comparative Study of Random Patterns for Digital Image Correlation

    NASA Astrophysics Data System (ADS)

    Stoilov, G.; Kavardzhikov, V.; Pashkouleva, D.

    2012-06-01

    Digital Image Correlation (DIC) is a computer based image analysis technique utilizing random patterns, which finds applications in experimental mechanics of solids and structures. In this paper a comparative study of three simulated random patterns is done. One of them is generated according to a new algorithm, introduced by the authors. A criterion for quantitative evaluation of random patterns after the calculation of their autocorrelation functions is introduced. The patterns' deformations are simulated numerically and realized experimentally. The displacements are measured by using the DIC method. Tensile tests are performed after printing the generated random patterns on surfaces of standard iron sheet specimens. It is found that the new designed random pattern keeps relatively good quality until reaching 20% deformation.

  5. [Realization of design regarding experimental research in the clinical real-world research].

    PubMed

    He, Q; Shi, J P

    2018-04-10

    Real world study (RWS), a further verification and supplement for explanatory randomized controlled trial to evaluate the effectiveness of intervention measures in real clinical environment, has increasingly become the focus in the field of research on medical and health care services. However, some people mistakenly equate real world study with observational research, and argue that intervention and randomization cannot be carried out in real world study. In fact, both observational and experimental design are the basic designs in real world study, while the latter usually refers to pragmatic randomized controlled trial and registry-based randomized controlled trial. Other nonrandomized controlled and adaptive designs can also be adopted in the RWS.

  6. An Experimental Study of Interventions for the Acquisition and Retention of Motivational Interviewing Skills among Probation Officers

    ERIC Educational Resources Information Center

    Asteris, Mark M., Jr.

    2012-01-01

    This study was designed to investigate the differences in Motivational Interviewing (MI) skill acquisition and retention among probation officers. This study had a randomized, experimental, pretest-posttest control group design using the MITI 3.1.1 and the VASE-R to measure MI skill acquisition and retention. A random sample (n = 24) of probation…

  7. Effect of Peer-Led Team Learning (PLTL) on Student Achievement, Attitude, and Self-Concept in College General Chemistry in Randomized and Quasi Experimental Designs

    ERIC Educational Resources Information Center

    Chan, Julia Y. K.; Bauer, Christopher F.

    2015-01-01

    This study investigated exam achievement and affective characteristics of students in general chemistry in a fully-randomized experimental design, contrasting Peer-Led Team Learning (PLTL) participation with a control group balanced for time-on-task and study activity. This study population included two independent first-semester courses with…

  8. Just-in-time consent: The ethical case for an alternative to traditional informed consent in randomized trials comparing an experimental intervention with usual care.

    PubMed

    Vickers, Andrew J; Young-Afat, Danny A; Ehdaie, Behfar; Kim, Scott Yh

    2018-02-01

    Informed consent for randomized trials often causes significant and persistent anxiety, distress and confusion to patients. Where an experimental treatment is compared to a standard care control, much of this burden is potentially avoidable in the control group. We propose a "just-in-time" consent in which consent discussions take place in two stages: an initial consent to research from all participants and a later specific consent to randomized treatment only from those assigned to the experimental intervention. All patients are first approached and informed about research procedures, such as questionnaires or tests. They are also informed that they might be randomly selected to receive an experimental treatment and that, if selected, they can learn more about the treatment and decide whether or not to accept it at that time. After randomization, control patients undergo standard clinical consent whereas patients randomized to the experimental procedure undergo a second consent discussion. Analysis would be by intent-to-treat, which protects the trial from selection bias, although not from poor acceptance of experimental treatment. The advantages of just-in-time consent stem from the fact that only patients randomized to the experimental treatment are subject to a discussion of that intervention. We hypothesize that this will reduce much of the patient's burden associated with the consent process, such as decisional anxiety, confusion and information overload. We recommend well-controlled studies to compare just-in-time and traditional consent, with endpoints to include characteristics of participants, distress and anxiety and participants' understanding of research procedures.

  9. RANDOMIZATION PROCEDURES FOR THE ANALYSIS OF EDUCATIONAL EXPERIMENTS.

    ERIC Educational Resources Information Center

    COLLIER, RAYMOND O.

    CERTAIN SPECIFIC ASPECTS OF HYPOTHESIS TESTS USED FOR ANALYSIS OF RESULTS IN RANDOMIZED EXPERIMENTS WERE STUDIED--(1) THE DEVELOPMENT OF THE THEORETICAL FACTOR, THAT OF PROVIDING INFORMATION ON STATISTICAL TESTS FOR CERTAIN EXPERIMENTAL DESIGNS AND (2) THE DEVELOPMENT OF THE APPLIED ELEMENT, THAT OF SUPPLYING THE EXPERIMENTER WITH MACHINERY FOR…

  10. Design approaches to experimental mediation☆

    PubMed Central

    Pirlott, Angela G.; MacKinnon, David P.

    2016-01-01

    Identifying causal mechanisms has become a cornerstone of experimental social psychology, and editors in top social psychology journals champion the use of mediation methods, particularly innovative ones when possible (e.g. Halberstadt, 2010, Smith, 2012). Commonly, studies in experimental social psychology randomly assign participants to levels of the independent variable and measure the mediating and dependent variables, and the mediator is assumed to causally affect the dependent variable. However, participants are not randomly assigned to levels of the mediating variable(s), i.e., the relationship between the mediating and dependent variables is correlational. Although researchers likely know that correlational studies pose a risk of confounding, this problem seems forgotten when thinking about experimental designs randomly assigning participants to levels of the independent variable and measuring the mediator (i.e., “measurement-of-mediation” designs). Experimentally manipulating the mediator provides an approach to solving these problems, yet these methods contain their own set of challenges (e.g., Bullock, Green, & Ha, 2010). We describe types of experimental manipulations targeting the mediator (manipulations demonstrating a causal effect of the mediator on the dependent variable and manipulations targeting the strength of the causal effect of the mediator) and types of experimental designs (double randomization, concurrent double randomization, and parallel), provide published examples of the designs, and discuss the strengths and challenges of each design. Therefore, the goals of this paper include providing a practical guide to manipulation-of-mediator designs in light of their challenges and encouraging researchers to use more rigorous approaches to mediation because manipulation-of-mediator designs strengthen the ability to infer causality of the mediating variable on the dependent variable. PMID:27570259

  11. Design approaches to experimental mediation.

    PubMed

    Pirlott, Angela G; MacKinnon, David P

    2016-09-01

    Identifying causal mechanisms has become a cornerstone of experimental social psychology, and editors in top social psychology journals champion the use of mediation methods, particularly innovative ones when possible (e.g. Halberstadt, 2010, Smith, 2012). Commonly, studies in experimental social psychology randomly assign participants to levels of the independent variable and measure the mediating and dependent variables, and the mediator is assumed to causally affect the dependent variable. However, participants are not randomly assigned to levels of the mediating variable(s), i.e., the relationship between the mediating and dependent variables is correlational. Although researchers likely know that correlational studies pose a risk of confounding, this problem seems forgotten when thinking about experimental designs randomly assigning participants to levels of the independent variable and measuring the mediator (i.e., "measurement-of-mediation" designs). Experimentally manipulating the mediator provides an approach to solving these problems, yet these methods contain their own set of challenges (e.g., Bullock, Green, & Ha, 2010). We describe types of experimental manipulations targeting the mediator (manipulations demonstrating a causal effect of the mediator on the dependent variable and manipulations targeting the strength of the causal effect of the mediator) and types of experimental designs (double randomization, concurrent double randomization, and parallel), provide published examples of the designs, and discuss the strengths and challenges of each design. Therefore, the goals of this paper include providing a practical guide to manipulation-of-mediator designs in light of their challenges and encouraging researchers to use more rigorous approaches to mediation because manipulation-of-mediator designs strengthen the ability to infer causality of the mediating variable on the dependent variable.

  12. Experimental study of a quantum random-number generator based on two independent lasers

    NASA Astrophysics Data System (ADS)

    Sun, Shi-Hai; Xu, Feihu

    2017-12-01

    A quantum random-number generator (QRNG) can produce true randomness by utilizing the inherent probabilistic nature of quantum mechanics. Recently, the spontaneous-emission quantum phase noise of the laser has been widely deployed for quantum random-number generation, due to its high rate, its low cost, and the feasibility of chip-scale integration. Here, we perform a comprehensive experimental study of a phase-noise-based QRNG with two independent lasers, each of which operates in either continuous-wave (CW) or pulsed mode. We implement the QRNG by operating the two lasers in three configurations, namely, CW + CW, CW + pulsed, and pulsed + pulsed, and demonstrate their trade-offs, strengths, and weaknesses.

  13. Change in Pulmonary Function after Incentive Spirometer Exercise in Children with Spastic Cerebral Palsy: A Randomized Controlled Study.

    PubMed

    Choi, Ja Young; Rha, Dong-wook; Park, Eun Sook

    2016-05-01

    The aim of this study was to investigate the effect of incentive spirometer exercise (ISE) on pulmonary function and maximal phonation time (MPT) in children with spastic cerebral palsy (CP). Fifty children with CP were randomly assigned to two groups: the experimental group and the control group. Both groups underwent comprehensive rehabilitation therapy. The experimental group underwent additional ISE. The forced vital capacity (FVC), forced expiratory volume at one second (FEV₁), FEV₁/FVC ratio, peak expiratory flow (PEF), and MPT were assessed as outcome measures before and after 4 weeks of training. There were significant improvements in FVC, FEV₁, PEF, and MPT in the experimental group, but not in the control group. In addition, the improvements in FVC, FEV₁, and MPT were significantly greater in the experimental group than in the control group. The results of this randomized controlled study support the use of ISE for enhancing pulmonary function and breath control for speech production in children with CP.

  14. Feasibility of quasi-random band model in evaluating atmospheric radiance

    NASA Technical Reports Server (NTRS)

    Tiwari, S. N.; Mirakhur, N.

    1980-01-01

    The use of the quasi-random band model in evaluating upwelling atmospheric radiation is investigated. The spectral transmittance and total band adsorptance are evaluated for selected molecular bands by using the line by line model, quasi-random band model, exponential sum fit method, and empirical correlations, and these are compared with the available experimental results. The atmospheric transmittance and upwelling radiance were calculated by using the line by line and quasi random band models and were compared with the results of an existing program called LOWTRAN. The results obtained by the exponential sum fit and empirical relations were not in good agreement with experimental results and their use cannot be justified for atmospheric studies. The line by line model was found to be the best model for atmospheric applications, but it is not practical because of high computational costs. The results of the quasi random band model compare well with the line by line and experimental results. The use of the quasi random band model is recommended for evaluation of the atmospheric radiation.

  15. Obstacles in Using Randomization Tests in Single-Case Experimentation.

    ERIC Educational Resources Information Center

    Kazdin, Alan E.

    1980-01-01

    Problems associated with randomization tests in single- case experiments are discussed. This article follows a discussion of randomization tests in single case studies in the same issue of this journal. (See TM 505 799; 505 801).(Author/JKS)

  16. Micro-Randomized Trials: An Experimental Design for Developing Just-in-Time Adaptive Interventions

    PubMed Central

    Klasnja, Predrag; Hekler, Eric B.; Shiffman, Saul; Boruvka, Audrey; Almirall, Daniel; Tewari, Ambuj; Murphy, Susan A.

    2015-01-01

    Objective This paper presents an experimental design, the micro-randomized trial, developed to support optimization of just-in-time adaptive interventions (JITAIs). JITAIs are mHealth technologies that aim to deliver the right intervention components at the right times and locations to optimally support individuals’ health behaviors. Micro-randomized trials offer a way to optimize such interventions by enabling modeling of causal effects and time-varying effect moderation for individual intervention components within a JITAI. Methods The paper describes the micro-randomized trial design, enumerates research questions that this experimental design can help answer, and provides an overview of the data analyses that can be used to assess the causal effects of studied intervention components and investigate time-varying moderation of those effects. Results Micro-randomized trials enable causal modeling of proximal effects of the randomized intervention components and assessment of time-varying moderation of those effects. Conclusions Micro-randomized trials can help researchers understand whether their interventions are having intended effects, when and for whom they are effective, and what factors moderate the interventions’ effects, enabling creation of more effective JITAIs. PMID:26651463

  17. Glutamine Randomized Studies in Early Life: The Unsolved Riddle of Experimental and Clinical Studies

    PubMed Central

    Briassouli, Efrossini; Briassoulis, George

    2012-01-01

    Glutamine may have benefits during immaturity or critical illness in early life but its effects on outcome end hardpoints are controversial. Our aim was to review randomized studies on glutamine supplementation in pups, infants, and children examining whether glutamine affects outcome. Experimental work has proposed various mechanisms of glutamine action but none of the randomized studies in early life showed any effect on mortality and only a few showed some effect on inflammatory response, organ function, and a trend for infection control. Although apparently safe in animal models (pups), premature infants, and critically ill children, glutamine supplementation does not reduce mortality or late onset sepsis, and its routine use cannot be recommended in these sensitive populations. Large prospectively stratified trials are needed to better define the crucial interrelations of “glutamine-heat shock proteins-stress response” in critical illness and to identify the specific subgroups of premature neonates and critically ill infants or children who may have a greater need for glutamine and who may eventually benefit from its supplementation. The methodological problems noted in the reviewed randomized experimental and clinical trials should be seriously considered in any future well-designed large blinded randomized controlled trial involving glutamine supplementation in critical illness. PMID:23019424

  18. Designing Studies That Would Address the Multilayered Nature of Health Care

    PubMed Central

    Pennell, Michael; Rhoda, Dale; Hade, Erinn M.; Paskett, Electra D.

    2010-01-01

    We review design and analytic methods available for multilevel interventions in cancer research with particular attention to study design, sample size requirements, and potential to provide statistical evidence for causal inference. The most appropriate methods will depend on the stage of development of the research and whether randomization is possible. Early on, fractional factorial designs may be used to screen intervention components, particularly when randomization of individuals is possible. Quasi-experimental designs, including time-series and multiple baseline designs, can be useful once the intervention is designed because they require few sites and can provide the preliminary evidence to plan efficacy studies. In efficacy and effectiveness studies, group-randomized trials are preferred when randomization is possible and regression discontinuity designs are preferred otherwise if assignment based on a quantitative score is possible. Quasi-experimental designs may be used, especially when combined with recent developments in analytic methods to reduce bias in effect estimates. PMID:20386057

  19. A Simulation Study on the Performance of the Simple Difference and Covariance-Adjusted Scores in Randomized Experimental Designs

    ERIC Educational Resources Information Center

    Petscher, Yaacov; Schatschneider, Christopher

    2011-01-01

    Research by Huck and McLean (1975) demonstrated that the covariance-adjusted score is more powerful than the simple difference score, yet recent reviews indicate researchers are equally likely to use either score type in two-wave randomized experimental designs. A Monte Carlo simulation was conducted to examine the conditions under which the…

  20. A School-Randomized Clinical Trial of an Integrated Social-Emotional Learning and Literacy Intervention: Impacts after 1 School Year

    ERIC Educational Resources Information Center

    Jones, Stephanie M.; Brown, Joshua L.; Hoglund, Wendy L. G.; Aber, J. Lawrence

    2010-01-01

    Objective: To report experimental impacts of a universal, integrated school-based intervention in social-emotional learning and literacy development on change over 1 school year in 3rd-grade children's social-emotional, behavioral, and academic outcomes. Method: This study employed a school-randomized, experimental design and included 942…

  1. Change in Pulmonary Function after Incentive Spirometer Exercise in Children with Spastic Cerebral Palsy: A Randomized Controlled Study

    PubMed Central

    Choi, Ja Young; Rha, Dong-wook

    2016-01-01

    Purpose The aim of this study was to investigate the effect of incentive spirometer exercise (ISE) on pulmonary function and maximal phonation time (MPT) in children with spastic cerebral palsy (CP). Materials and Methods Fifty children with CP were randomly assigned to two groups: the experimental group and the control group. Both groups underwent comprehensive rehabilitation therapy. The experimental group underwent additional ISE. The forced vital capacity (FVC), forced expiratory volume at one second (FEV1), FEV1/FVC ratio, peak expiratory flow (PEF), and MPT were assessed as outcome measures before and after 4 weeks of training. Results There were significant improvements in FVC, FEV1, PEF, and MPT in the experimental group, but not in the control group. In addition, the improvements in FVC, FEV1, and MPT were significantly greater in the experimental group than in the control group. Conclusion The results of this randomized controlled study support the use of ISE for enhancing pulmonary function and breath control for speech production in children with CP. PMID:26996580

  2. Effects of far-infrared irradiation on myofascial neck pain: a randomized, double-blind, placebo-controlled pilot study.

    PubMed

    Lai, Chien-Hung; Leung, Ting-Kai; Peng, Chih-Wei; Chang, Kwang-Hwa; Lai, Ming-Jun; Lai, Wen-Fu; Chen, Shih-Ching

    2014-02-01

    The objective of this study was to determine the relative efficacy of irradiation using a device containing a far-infrared emitting ceramic powder (cFIR) for the management of chronic myofascial neck pain compared with a control treatment. This was a randomized, double-blind, placebo-controlled pilot study. The study comprised 48 patients with chronic, myofascial neck pain. Patients were randomly assigned to the experimental group or the control (sham-treatment) group. The patients in the experimental group wore a cFIR neck device for 1 week, and the control group wore an inert neck device for 1 week. Quantitative measurements based on a visual analogue scale (VAS) scoring of pain, a sleep quality assessment, pressure-pain threshold (PPT) testing, muscle tone and compliance analysis, and skin temperature analysis were obtained. Both the experimental and control groups demonstrated significant improvement in pain scores. However, no statistically significant difference in the pain scores was observed between the experimental and control groups. Significant decreases in muscle stiffness in the upper regions of the trapezius muscles were reported in the experimental group after 1 week of treatment. Short-term treatment using the cFIR neck device partly reduced muscle stiffness. Although the differences in the VAS and PPT scores for the experimental and control groups were not statistically significant, the improvement in muscle stiffness in the experimental group warrants further investigation of the long-term effects of cFIR treatment for pain management.

  3. Testing a Violence-Prevention Intervention for Incarcerated Women Using a Randomized Control Trial

    ERIC Educational Resources Information Center

    Kubiak, Sheryl Pimlott; Kim, Woo Jong; Fedock, Gina; Bybee, Deborah

    2015-01-01

    Objective: Beyond Violence (BV), a new prevention program for women with assaultive offenses, demonstrated feasibility in previous studies. This study's purpose is to assess the efficacy of BV using a randomized control trial. Method: Eligible women were randomly assigned to treatment as usual (TAU) and the experimental condition (BV). Measures of…

  4. Dynamic probability of reinforcement for cooperation: Random game termination in the centipede game.

    PubMed

    Krockow, Eva M; Colman, Andrew M; Pulford, Briony D

    2018-03-01

    Experimental games have previously been used to study principles of human interaction. Many such games are characterized by iterated or repeated designs that model dynamic relationships, including reciprocal cooperation. To enable the study of infinite game repetitions and to avoid endgame effects of lower cooperation toward the final game round, investigators have introduced random termination rules. This study extends previous research that has focused narrowly on repeated Prisoner's Dilemma games by conducting a controlled experiment of two-player, random termination Centipede games involving probabilistic reinforcement and characterized by the longest decision sequences reported in the empirical literature to date (24 decision nodes). Specifically, we assessed mean exit points and cooperation rates, and compared the effects of four different termination rules: no random game termination, random game termination with constant termination probability, random game termination with increasing termination probability, and random game termination with decreasing termination probability. We found that although mean exit points were lower for games with shorter expected game lengths, the subjects' cooperativeness was significantly reduced only in the most extreme condition with decreasing computer termination probability and an expected game length of two decision nodes. © 2018 Society for the Experimental Analysis of Behavior.

  5. The effect of asthma education program on knowledge of school teachers: a randomized controlled trial.

    PubMed

    Kawafha, Mariam M; Tawalbeh, Loai Issa

    2015-04-01

    The purpose of this study was to examine the effect of an asthma education program on schoolteachers' knowledge. Pre-test-post-test experimental randomized controlled design was used. A multistage-cluster sampling technique was used to randomly select governorate, primary schools, and schoolteachers. Schoolteachers were randomly assigned either to the experimental group (n = 36) and attended three educational sessions or to the control group (n = 38) who did not receive any intervention. Knowledge about asthma was measured using the Asthma General Knowledge Questionnaire for Adults (AGKQA). The results indicated that teachers in the experimental group showed significantly (p < .001) higher knowledge of asthma in the first post-test and the second post-test compared with those in the control group. Implementing asthma education enhanced schoolteachers' knowledge of asthma. The asthma education program should target schoolteachers to improve knowledge about asthma. © The Author(s) 2014.

  6. Effect of Rosa damascene aromatherapy on sleep quality in cardiac patients: a randomized controlled trial.

    PubMed

    Hajibagheri, Ali; Babaii, Atye; Adib-Hajbaghery, Mohsen

    2014-08-01

    Sleep disorders are common among patients hospitalized in coronary care unit (CCU). This study aimed to investigate the effect of Rosa damascene aromatherapy on sleep quality of patients hospitalized in CCU. In this randomized controlled trial, 60 patients who met the inclusion criteria were conveniently sampled and randomly allocated to the experimental and control groups. Patients in the control group received routine care. In the experimental group, patients received routine care and Rosa damascene aromatherapy for three subsequent nights. In the both groups the sleep quality was assessed using the Pittsburgh Sleep Quality Index. After the study, the mean scores of five domains of Pittsburg Sleep Quality Index as well as the mean of total score of the index in the experimental group were significantly lower than the control group. Rosa damascene aromatherapy can significantly improve the sleep quality of patients hospitalized in CCUs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Design of a factorial experiment with randomization restrictions to assess medical device performance on vascular tissue.

    PubMed

    Diestelkamp, Wiebke S; Krane, Carissa M; Pinnell, Margaret F

    2011-05-20

    Energy-based surgical scalpels are designed to efficiently transect and seal blood vessels using thermal energy to promote protein denaturation and coagulation. Assessment and design improvement of ultrasonic scalpel performance relies on both in vivo and ex vivo testing. The objective of this work was to design and implement a robust, experimental test matrix with randomization restrictions and predictive statistical power, which allowed for identification of those experimental variables that may affect the quality of the seal obtained ex vivo. The design of the experiment included three factors: temperature (two levels); the type of solution used to perfuse the artery during transection (three types); and artery type (two types) resulting in a total of twelve possible treatment combinations. Burst pressures of porcine carotid and renal arteries sealed ex vivo were assigned as the response variable. The experimental test matrix was designed and carried out as a split-plot experiment in order to assess the contributions of several variables and their interactions while accounting for randomization restrictions present in the experimental setup. The statistical software package SAS was utilized and PROC MIXED was used to account for the randomization restrictions in the split-plot design. The combination of temperature, solution, and vessel type had a statistically significant impact on seal quality. The design and implementation of a split-plot experimental test-matrix provided a mechanism for addressing the existing technical randomization restrictions of ex vivo ultrasonic scalpel performance testing, while preserving the ability to examine the potential effects of independent factors or variables. This method for generating the experimental design and the statistical analyses of the resulting data are adaptable to a wide variety of experimental problems involving large-scale tissue-based studies of medical or experimental device efficacy and performance.

  8. Impact of Thematic Approach on Communication Skill in Preschool

    ERIC Educational Resources Information Center

    Ashokan, Varun; Venugopal, Kalpana

    2016-01-01

    The study investigated the effects of thematic approach on communication skills for preschool children. The study was a quasi experimental non-equivalent pretest-post-test control group design whereby 5-6 year old preschool children (n = 49) were randomly assigned to an experimental and a control group. The experimental group students were exposed…

  9. The Modern Design of Experiments for Configuration Aerodynamics: A Case Study

    NASA Technical Reports Server (NTRS)

    DeLoach, Richard

    2006-01-01

    The effects of slowly varying and persisting covariate effects on the accuracy and precision of experimental result is reviewed, as is the rationale for run-order randomization as a quality assurance tactic employed in the Modern Design of Experiments (MDOE) to defend against such effects. Considerable analytical complexity is introduced by restrictions on randomization in configuration aerodynamics tests because they involve hard-to-change configuration variables that cannot be randomized conveniently. Tradeoffs are examined between quality and productivity associated with varying degrees of rigor in accounting for such randomization restrictions. Certain characteristics of a configuration aerodynamics test are considered that may justify a relaxed accounting for randomization restrictions to achieve a significant reduction in analytical complexity with a comparably negligible adverse impact on the validity of the experimental results.

  10. The Effects of Total Physical Response by Storytelling and the Traditional Teaching Styles of a Foreign Language in a Selected High School

    ERIC Educational Resources Information Center

    Kariuki, Patrick N. K.; Bush, Elizabeth Danielle

    2008-01-01

    The purpose of this study was to examine the effects of Total Physical Response by Storytelling and the traditional teaching method on a foreign language in a selected high school. The sample consisted of 30 students who were randomly selected and randomly assigned to experimental and control group. The experimental group was taught using Total…

  11. Randomized Controlled Studies and Alternative Designs in Outcome Studies: Challenges and Opportunities

    ERIC Educational Resources Information Center

    Shadish, William R.

    2011-01-01

    This article reviews several decades of the author's meta-analytic and experimental research on the conditions under which nonrandomized experiments can approximate the results from randomized experiments (REs). Several studies make clear that we can expect accurate effect estimates from the regression discontinuity design, though its statistical…

  12. Using Non-experimental Data to Estimate Treatment Effects

    PubMed Central

    Stuart, Elizabeth A.; Marcus, Sue M.; Horvitz-Lennon, Marcela V.; Gibbons, Robert D.; Normand, Sharon-Lise T.

    2009-01-01

    While much psychiatric research is based on randomized controlled trials (RCTs), where patients are randomly assigned to treatments, sometimes RCTs are not feasible. This paper describes propensity score approaches, which are increasingly used for estimating treatment effects in non-experimental settings. The primary goal of propensity score methods is to create sets of treated and comparison subjects who look as similar as possible, in essence replicating a randomized experiment, at least with respect to observed patient characteristics. A study to estimate the metabolic effects of antipsychotic medication in a sample of Florida Medicaid beneficiaries with schizophrenia illustrates methods. PMID:20563313

  13. An Experimental Study for Effectiveness of Super-Learning Technique at Elementary Level in Pakistan

    ERIC Educational Resources Information Center

    Shafqat, Hussain; Muhammad, Sarwar; Imran, Yousaf; Naemullah; Inamullah

    2010-01-01

    The objective of the study was to experience the effectiveness of super-learning technique of teaching at elementary level. The study was conducted with 8th grade students at a public sector school. Pre-test and post-test control group designs were used. Experimental and control groups were formed randomly, the experimental group (N = 62),…

  14. True and Quasi-Experimental Designs. ERIC/AE Digest.

    ERIC Educational Resources Information Center

    Gribbons, Barry; Herman, Joan

    Among the different types of experimental design are two general categories: true experimental designs and quasi- experimental designs. True experimental designs include more than one purposively created group, common measured outcomes, and random assignment. Quasi-experimental designs are commonly used when random assignment is not practical or…

  15. Randomizing Roaches: Exploring the "Bugs" of Randomization in Experimental Design

    ERIC Educational Resources Information Center

    Wagler, Amy; Wagler, Ron

    2014-01-01

    Understanding the roles of random selection and random assignment in experimental design is a central learning objective in most introductory statistics courses. This article describes an activity, appropriate for a high school or introductory statistics course, designed to teach the concepts, values and pitfalls of random selection and assignment…

  16. Assessing effects of a semi-customized experimental cervical pillow on symptomatic adults with chronic neck pain with and without headache

    PubMed Central

    Erfanian, Parham; Tenzif, Siamak; Guerriero, Rocco C

    2004-01-01

    Objective To determine the effects of a semi-customized experimental cervical pillow on symptomatic adults with chronic neck pain (with and without headache) during a four week study. Design A randomized controlled trial. Sample size Thirty-six adults were recruited for the trial, and randomly assigned to experimental or non-experimental groups of 17 and 19 participants respectively. Subjects Adults with chronic biomechanical neck pain who were recruited from the Canadian Memorial Chiropractic College (CMCC) Walk-in Clinic. Outcome measures Subjective findings were assessed using a mail-in self-report daily pain diary, and the CMCC Neck Disability Index (NDI). Statistical analysis Using repeated measure analysis of variance weekly NDI scores, average weekly AM and PM pain scores between the experimental and non-experimental groups were compared throughout the study. Results The experimental group had statistically significant lower NDI scores (p < 0.05) than the non-experimental group. The average weekly AM scores were lower and statistically significant (p < 0.05) in the experimental group. The PM scores in the experimental group were lower but not statistically significant than the other group. Conclusions The study results show that compared to conventional pillows, this experimental semi-customized cervical pillow was effective in reducing low-level neck pain intensity, especially in the morning following its use in a 4 week long study. PMID:17549216

  17. Divergence of Scientific Heuristic Method and Direct Algebraic Instruction

    ERIC Educational Resources Information Center

    Calucag, Lina S.

    2016-01-01

    This is an experimental study, made used of the non-randomized experimental and control groups, pretest-posttest designs. The experimental and control groups were two separate intact classes in Algebra. For a period of twelve sessions, the experimental group was subjected to the scientific heuristic method, but the control group instead was given…

  18. 76 FR 28788 - Proposed Data Collections Submitted for Public Comment and Recommendations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-18

    ... studies have been quasi-experimental designs focused on short term workload assessments as outcomes. The... experimental research to define further the effectiveness and cost-benefit of MSD control interventions. A... prospective experimental design (multiple baselines across groups with randomization). These interventions...

  19. The Effects of a Computerized Study Program on the Acquisition of Science Vocabulary

    ERIC Educational Resources Information Center

    Rollins, Karen F.

    2012-01-01

    The following study examined the difference in science vocabulary acquisition comparing computer-assisted learning and a traditional study review sheet. Fourth and fifth grade students from a suburban school in central Texas were randomly selected and randomly assigned to either experimental group or control group. Both groups were given a…

  20. Comparison of Cognitive Orientation to daily Occupational Performance and conventional occupational therapy on occupational performance in individuals with stroke: A randomized controlled trial.

    PubMed

    Ahn, Si-Nae; Yoo, Eun-Young; Jung, Min-Ye; Park, Hae-Yean; Lee, Ji-Yeon; Choi, Yoo-Im

    2017-01-01

    Cognitive Orientation to daily Occupational Performance (CO-OP) approach based on cognitive strategy in occupational therapy. To investigate the effects of CO-OP approach on occupational performance in individuals with hemiparetic stroke. This study was designed as a 5-week, randomized, single-blind. Forty-three participants who had a diagnosis of first stroke were enrolled in this study. The participants were randomly assigned to the experimental group (n = 20) or the control group (n = 23). The experimental group conducted CO-OP approach while the control group conducted conventional occupational therapy based on occupational performance components. This study measured Canadian Occupational Performance Measure (COPM) and Performance Quality Rating Scale (PQRS). Outcome measurements were performed at baseline and post-intervention. After training, the scores of COPM and PQRS in trained task were significantly higher for the score in the experimental group than the control group. In addition, the non-trained task was significantly higher for the score in the experimental group than the control group in COPM and the PQRS. This study suggests that the CO-OP approach is beneficial effects on the occupational performance to improvement in individuals with hemiparetic stroke, and have positive effects on generalization and transfer of acquired skills.

  1. The need for randomization in animal trials: an overview of systematic reviews.

    PubMed

    Hirst, Jennifer A; Howick, Jeremy; Aronson, Jeffrey K; Roberts, Nia; Perera, Rafael; Koshiaris, Constantinos; Heneghan, Carl

    2014-01-01

    Randomization, allocation concealment, and blind outcome assessment have been shown to reduce bias in human studies. Authors from the Collaborative Approach to Meta Analysis and Review of Animal Data from Experimental Studies (CAMARADES) collaboration recently found that these features protect against bias in animal stroke studies. We extended the scope the work from CAMARADES to include investigations of treatments for any condition. We conducted an overview of systematic reviews. We searched Medline and Embase for systematic reviews of animal studies testing any intervention (against any control) and we included any disease area and outcome. We included reviews comparing randomized versus not randomized (but otherwise controlled), concealed versus unconcealed treatment allocation, or blinded versus unblinded outcome assessment. Thirty-one systematic reviews met our inclusion criteria: 20 investigated treatments for experimental stroke, 4 reviews investigated treatments for spinal cord diseases, while 1 review each investigated treatments for bone cancer, intracerebral hemorrhage, glioma, multiple sclerosis, Parkinson's disease, and treatments used in emergency medicine. In our sample 29% of studies reported randomization, 15% of studies reported allocation concealment, and 35% of studies reported blinded outcome assessment. We pooled the results in a meta-analysis, and in our primary analysis found that failure to randomize significantly increased effect sizes, whereas allocation concealment and blinding did not. In our secondary analyses we found that randomization, allocation concealment, and blinding reduced effect sizes, especially where outcomes were subjective. Our study demonstrates the need for randomization, allocation concealment, and blind outcome assessment in animal research across a wide range of outcomes and disease areas. Since human studies are often justified based on results from animal studies, our results suggest that unduly biased animal studies should not be allowed to constitute part of the rationale for human trials.

  2. Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship-Quasi-Experimental Designs.

    PubMed

    Schweizer, Marin L; Braun, Barbara I; Milstone, Aaron M

    2016-10-01

    Quasi-experimental studies evaluate the association between an intervention and an outcome using experiments in which the intervention is not randomly assigned. Quasi-experimental studies are often used to evaluate rapid responses to outbreaks or other patient safety problems requiring prompt, nonrandomized interventions. Quasi-experimental studies can be categorized into 3 major types: interrupted time-series designs, designs with control groups, and designs without control groups. This methods paper highlights key considerations for quasi-experimental studies in healthcare epidemiology and antimicrobial stewardship, including study design and analytic approaches to avoid selection bias and other common pitfalls of quasi-experimental studies. Infect Control Hosp Epidemiol 2016;1-6.

  3. Efficacy of Visual-Acoustic Biofeedback Intervention for Residual Rhotic Errors: A Single-Subject Randomization Study

    ERIC Educational Resources Information Center

    Byun, Tara McAllister

    2017-01-01

    Purpose: This study documented the efficacy of visual-acoustic biofeedback intervention for residual rhotic errors, relative to a comparison condition involving traditional articulatory treatment. All participants received both treatments in a single-subject experimental design featuring alternating treatments with blocked randomization of…

  4. Efficiency of a Care Coordination Model: A Randomized Study with Stroke Patients

    ERIC Educational Resources Information Center

    Claiborne, Nancy

    2006-01-01

    Objectives: This study investigated the efficiency of a social work care coordination model for stroke patients. Care coordination addresses patient care and treatment resources across the health care system to reduce risk, improve clinical outcomes, and maximize efficiency. Method: A randomly assigned, pre-post experimental design measured…

  5. The Role of Friends' Disruptive Behavior in the Development of Children's Tobacco Experimentation: Results from a Preventive Intervention Study

    ERIC Educational Resources Information Center

    van Lier, Pol A. C.; Huizink, Anja; Vuijk, Patricia

    2011-01-01

    Having friends who engage in disruptive behavior in childhood may be a risk factor for childhood tobacco experimentation. This study tested the role of friends' disruptive behavior as a mediator of the effects of a classroom based intervention on children's tobacco experimentation. 433 Children (52% males) were randomly assigned to the Good…

  6. Scaffolding Voluntary Summer Reading for Children in Grades 3 to 5: An Experimental Study

    ERIC Educational Resources Information Center

    Kim, James S.; White, Thomas G.

    2008-01-01

    The effects of a voluntary summer reading intervention with teacher and parent scaffolding were investigated in an experimental study. A total of 24 teachers and 400 children in Grades 3, 4, and 5 were randomly assigned to one of four experimental conditions: control, books only, books with oral reading scaffolding, and books with oral reading and…

  7. 75 FR 43172 - Maternal, Infant, and Early Childhood Home Visiting Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ... the evaluation results have been published in a peer-reviewed journal; or (bb) quasi-experimental... design (i.e. randomized controlled trial [RCT] or quasi-experimental design [QED]), level of attrition... a quasi-experimental design as a study design in which sample members are selected for the program...

  8. Design of a factorial experiment with randomization restrictions to assess medical device performance on vascular tissue

    PubMed Central

    2011-01-01

    Background Energy-based surgical scalpels are designed to efficiently transect and seal blood vessels using thermal energy to promote protein denaturation and coagulation. Assessment and design improvement of ultrasonic scalpel performance relies on both in vivo and ex vivo testing. The objective of this work was to design and implement a robust, experimental test matrix with randomization restrictions and predictive statistical power, which allowed for identification of those experimental variables that may affect the quality of the seal obtained ex vivo. Methods The design of the experiment included three factors: temperature (two levels); the type of solution used to perfuse the artery during transection (three types); and artery type (two types) resulting in a total of twelve possible treatment combinations. Burst pressures of porcine carotid and renal arteries sealed ex vivo were assigned as the response variable. Results The experimental test matrix was designed and carried out as a split-plot experiment in order to assess the contributions of several variables and their interactions while accounting for randomization restrictions present in the experimental setup. The statistical software package SAS was utilized and PROC MIXED was used to account for the randomization restrictions in the split-plot design. The combination of temperature, solution, and vessel type had a statistically significant impact on seal quality. Conclusions The design and implementation of a split-plot experimental test-matrix provided a mechanism for addressing the existing technical randomization restrictions of ex vivo ultrasonic scalpel performance testing, while preserving the ability to examine the potential effects of independent factors or variables. This method for generating the experimental design and the statistical analyses of the resulting data are adaptable to a wide variety of experimental problems involving large-scale tissue-based studies of medical or experimental device efficacy and performance. PMID:21599963

  9. Influence of Problem Based Learning on Critical Thinking Skills and Competence Class VIII SMPN 1 Gunuang Omeh, 2016/2017

    NASA Astrophysics Data System (ADS)

    Aswan, D. M.; Lufri, L.; Sumarmin, R.

    2018-04-01

    This research intends to determine the effect of Problem Based Learning models on students' critical thinking skills and competences. This study was a quasi-experimental research. The population of the study was the students of class VIII SMPN 1 Subdistrict Gunuang Omeh. Random sample selection is done by randomizing the class. Sample class that was chosen VIII3 as an experimental class given that treatment study based on problems and class VIII1 as control class that treatment usually given study. Instrument that used to consist of critical thinking test, cognitive tests, observation sheet of affective and psychomotor. Independent t-test and Mann Whitney U test was used for the analysis. Results showed that there was significant difference (sig <0.05) between control and experimental group. The conclusion of this study was Problem Based Learning models affected the students’ critical thinking skills and competences.

  10. Experimental transmission of Corynebacterium pseudotuberculosis in horses by house flies

    USDA-ARS?s Scientific Manuscript database

    The route of infection of pigeon fever remains undetermined. The purpose of this study was to investigate house flies (Musca domestica L.) as vectors of Corynebacterium pseudotuberculosis in horses. Eight ponies were used in a randomized, controlled, blinded experimental study. Ten wounds were creat...

  11. Evaluation of the Oral Tolerance of Three Fluoride Toothpaste Formulations in a Dry Mouth Population: Results from Two Randomized Studies.

    PubMed

    Jose, Anto; Ward, John; Shneyer, Lucy; Skinner, Jacob; Jeal, Nathan; Cronin, Matthew; Bosma, Mary Lynn

    2016-03-01

    To evaluate the oral tolerance of three experimental toothpaste formulations containing sodium fluoride (NaF), compared with two marketed sodium monofluorophosphate (SMFP)-containing biotène® toothpastes, in a dry mouth population after 14 days (primary objective) and 7 days (secondary objective) of use. Toothpastes were tested in two separate dual-site, examiner-blind, randomized, parallel group studies in subjects (35-84 years) with self-reported dry mouth. Oral soft tissue (OST) and oral hard tissue (OHT) examinations were performed at screening, followed by a 7- to 28-day wash-in period using a control toothpaste. Subjects were randomized to receive a NaF-containing toothpaste (Study 1: commercially available toothpaste Pronamel® for Children, n = 82; Study 2: experimental plaque biofilm-loosening formula [PBF] toothpaste, n = 79; or experimental Gentle Mint toothpaste, n = 78) or a reference toothpaste (Study 1: biotène® Fresh Mint Original toothpaste [previously marketed formulation], n = 82; Study 2: biotène® Gentle Mint Gel toothpaste [previously marketed formulation], n = 77) during the 14-day treatment phase. Subjects brushed their teeth twice daily for one timed minute with a ribbon of toothpaste to cover the head of the toothbrush provided. Subjects received further OST and OHT examinations at Day 1 and Day 15, and an additional OST examination at Day 8. Adverse events (AEs) and serious AEs (SAEs) were reported throughout the study. Study 1: At Day 15, 42 oral treatment-emergent AEs (TEAEs) were reported in 33 subjects, of which seven in five subjects (commercially available toothpaste Pronamel for Children: n = 2; control: n = 3) were considered to be treatment-related. One SAE (dyspnea) was reported in a participant who was randomized but withdrew from the study before receiving the allocated toothpaste. Study 2: At Day 15, 41 oral TEAEs were reported in 38 subjects, of which two in two subjects (experimental Gentle Mint toothpaste: n = 1; control: n = 1) were considered treatment-related, according to the investigator. No SAEs were reported. In both studies, the experimental and reference toothpastes were well tolerated after 7 and 14 days of use. The experimental NaF-containing toothpastes offer potential alternatives to individuals with dry mouth.

  12. What Does a Random Line Look Like: An Experimental Study

    ERIC Educational Resources Information Center

    Turner, Nigel E.; Liu, Eleanor; Toneatto, Tony

    2011-01-01

    The study examined the perception of random lines by people with gambling problems compared to people without gambling problems. The sample consisted of 67 probable pathological gamblers and 46 people without gambling problems. Participants completed a number of questionnaires about their gambling and were then presented with a series of random…

  13. Assessing Sensitivity of Early Head Start Study Findings to Manipulated Randomization Threats

    ERIC Educational Resources Information Center

    Green, Sheridan

    2013-01-01

    Increasing demands for design rigor and an emphasis on evidence-based practice on a national level indicated a need for further guidance related to successful implementation of randomized studies in education. Rigorous and meaningful experimental research and its conclusions help establish a valid theoretical and evidence base for educational…

  14. Randomization and Data-Analysis Items in Quality Standards for Single-Case Experimental Studies

    ERIC Educational Resources Information Center

    Heyvaert, Mieke; Wendt, Oliver; Van den Noortgate, Wim; Onghena, Patrick

    2015-01-01

    Reporting standards and critical appraisal tools serve as beacons for researchers, reviewers, and research consumers. Parallel to existing guidelines for researchers to report and evaluate group-comparison studies, single-case experimental (SCE) researchers are in need of guidelines for reporting and evaluating SCE studies. A systematic search was…

  15. Effects of leisure education on self-rated health among older adults.

    PubMed

    Chang, Liang-Chih; Yu, Ping; Jeng, Mei-Yuan

    2015-01-01

    This study examined whether a leisure education program could promote leisure autonomy and self-rated health (SRH) among older adults. A pretest-posttest randomized experimental design was conducted. Subjects were randomly assigned to either an experimental group (n = 30) or a control group (n = 30). Data related to leisure autonomy and SRH were collected shortly before and after the experiment. Pretest and posttest data were analyzed using an analysis of covariance. The results indicated that the average posttest scores of leisure autonomy and SRH in the experimental group were significantly higher than those in the control group. Implications of the results are discussed.

  16. A Comparison of Single Sample and Bootstrap Methods to Assess Mediation in Cluster Randomized Trials

    ERIC Educational Resources Information Center

    Pituch, Keenan A.; Stapleton, Laura M.; Kang, Joo Youn

    2006-01-01

    A Monte Carlo study examined the statistical performance of single sample and bootstrap methods that can be used to test and form confidence interval estimates of indirect effects in two cluster randomized experimental designs. The designs were similar in that they featured random assignment of clusters to one of two treatment conditions and…

  17. Theoretical and Experimental Investigation of Random Gust Loads Part I : Aerodynamic Transfer Function of a Simple Wing Configuration in Incompressible Flow

    NASA Technical Reports Server (NTRS)

    Hakkinen, Raimo J; Richardson, A S , Jr

    1957-01-01

    Sinusoidally oscillating downwash and lift produced on a simple rigid airfoil were measured and compared with calculated values. Statistically stationary random downwash and the corresponding lift on a simple rigid airfoil were also measured and the transfer functions between their power spectra determined. The random experimental values are compared with theoretically approximated values. Limitations of the experimental technique and the need for more extensive experimental data are discussed.

  18. Impacts of Dialogical Storybook Reading on Young Children's Reading Attitudes and Vocabulary Development

    ERIC Educational Resources Information Center

    Kotaman, Huseyin

    2013-01-01

    The current study assessed the impact of parents' dialogical storybook reading on their children's receptive vocabulary and reading attitudes. Forty parents and their preschoolers participated in the study. Parents were randomly assigned to experimental or control groups. The experimental group received dialogical storybook reading training.…

  19. Accelerating Recovery from Poverty: Prevention Effects for Recently Separated Mothers

    ERIC Educational Resources Information Center

    Forgatch, Marion S.; DeGarmo, David S.

    2007-01-01

    This study evaluated benefits of a preventive intervention to the living standards of recently separated mothers. In the Oregon Divorce Study's randomized experimental design, data were collected 5 times over 30 months and evaluated with Hierarchical Linear Growth Models. Relative to their no-intervention control counterparts, experimental mothers…

  20. An Experimental Test of the Effects of Gender Constancy on Sex Typing

    ERIC Educational Resources Information Center

    Arthur, Andrea E.; Bigler, Rebecca S.; Ruble, Diane N.

    2009-01-01

    This study provides an experimental test of the hypothesis that level of gender constancy understanding affects children's sex typing. Preschool-age children (N = 62, mean age = 47 months) were randomly assigned to experimental lessons that taught that biological traits (including gender) are either fixed (pro-constancy condition) or mutable…

  1. The Question of Education Science: "Experiment"ism Versus "Experimental"ism

    ERIC Educational Resources Information Center

    Howe, Kenneth R.

    2005-01-01

    The ascendant view in the current debate about education science -- experimentism -- is a reassertion of the randomized experiment as the methodological gold standard. Advocates of this view have ignored, not answered, long-standing criticisms of the randomized experiment: its frequent impracticality, its lack of external validity, its confinement…

  2. Biases in Estimating Treatment Effects Due to Attrition in Randomized Controlled Trials and Cluster Randomized Controlled Trials: A Simulation Study

    ERIC Educational Resources Information Center

    Dong, Nianbo; Lipsey, Mark W.

    2011-01-01

    Attrition occurs when study participants who were assigned to the treatment and control conditions do not provide outcome data and thus do not contribute to the estimation of the treatment effects. It is very common in experimental studies in education as illustrated, for instance, in a meta-analysis studying "the effects of attrition on baseline…

  3. The Role of Exposure Condition in the Effectiveness of Explicit Correction

    ERIC Educational Resources Information Center

    Yilmaz, Yucel

    2016-01-01

    This article reports on a study that investigated the effects of two feedback exposure conditions on the acquisition of two Turkish morphemes. The study followed a randomized experimental design with an immediate and a delayed posttest. Forty-two Chinese-speaking learners of Turkish were randomly assigned to one of three groups: receivers,…

  4. Visual Literacy and the Integration of Parametric Modeling in the Problem-Based Curriculum

    ERIC Educational Resources Information Center

    Assenmacher, Matthew Benedict

    2013-01-01

    This quasi-experimental study investigated the application of visual literacy skills in the form of parametric modeling software in relation to traditional forms of sketching. The study included two groups of high school technical design students. The control and experimental groups involved in the study consisted of two randomly selected groups…

  5. Effects of Eight Week Plyometric Study on the Balance Performance of Hearing Impaired Athletes

    ERIC Educational Resources Information Center

    Nacaroglu, Ersin; Karakoc, Onder

    2018-01-01

    This is an experimental study and it was aimed to identify the effects of 8-week plyometric training of hearing-impaired athletes on balance. 24 Male hearing-impaired volleyball players participated in the study. Random method was used when experimental and control groups were identified. Subjects used in the study were divided into two groups as…

  6. Using Propensity Scores in Quasi-Experimental Designs to Equate Groups

    ERIC Educational Resources Information Center

    Lane, Forrest C.; Henson, Robin K.

    2010-01-01

    Education research rarely lends itself to large scale experimental research and true randomization, leaving the researcher to quasi-experimental designs. The problem with quasi-experimental research is that underlying factors may impact group selection and lead to potentially biased results. One way to minimize the impact of non-randomization is…

  7. Pilot study of the Korean Parent Training Program using a partial group randomized experimental study

    PubMed Central

    Kim, Eunjung; Cain, Kevin; Boutain, Doris; Chun, Jin-Joo; Kim, Sangho; Im, Hyesang

    2017-01-01

    Problems Korean American (KA) children experience mental health problems due to difficulties in parenting dysfunction complicated by living in two cultures. Methods Korean Parent Training Program (KPTP) was pilot tested with 48 KA mothers of children (ages 3–8) using partial group randomized controlled experimental study design. Self-report survey and observation data were gathered. Findings Analyses using generalized estimating equation indicated the intervention group mothers increased effective parenting and their children decreased behavior problems and reported less acculturation conflict with mothers. Conclusions The KPTP is a promising way to promote effective parenting and increase positive child mental health in KA families. PMID:24645901

  8. Effect of Strategy Training on Vocabulary in EFL Contexts

    ERIC Educational Resources Information Center

    Ostovar-Namaghi, Seyd Ali; Rajaee, Mehdi

    2013-01-01

    Sixty Iranian high school EFL learners between 14 and 16 males participated in this study were randomly divided into two groups; experimental, and control. As the study aimed to know whether vocabulary strategy training effects on vocabulary learning of Iranian students, at first the control and experimental group were given a writing per-test…

  9. Replicating Experimental Impact Estimates Using a Regression Discontinuity Approach. NCEE 2012-4025

    ERIC Educational Resources Information Center

    Gleason, Philip M.; Resch, Alexandra M.; Berk, Jillian A.

    2012-01-01

    This NCEE Technical Methods Paper compares the estimated impacts of an educational intervention using experimental and regression discontinuity (RD) study designs. The analysis used data from two large-scale randomized controlled trials--the Education Technology Evaluation and the Teach for America Study--to provide evidence on the performance of…

  10. The Effects of Death Anxiety and Mode of "Case Study" Presentation on Shifts of Attitude toward Euthanasia.

    ERIC Educational Resources Information Center

    Hart, Edward J.

    1978-01-01

    College students (N = 18) were randomized to one of two experimental treatments: a video tape presentation of a burn victim, and a written narrative of the same "case study." There appeared to be significant differences in attitudes toward euthanasia between experimental groups. (Authors)

  11. Experimental Evaluations of Elementary Science Programs: A Best-Evidence Synthesis

    ERIC Educational Resources Information Center

    Slavin, Robert E.; Lake, Cynthia; Hanley, Pam; Thurston, Allen

    2014-01-01

    This article presents a systematic review of research on the achievement outcomes of all types of approaches to teaching science in elementary schools. Study inclusion criteria included use of randomized or matched control groups, a study duration of at least 4 weeks, and use of achievement measures independent of the experimental treatment. A…

  12. Impact of referral source and study applicants' preference for randomly assigned service on research enrollment, service engagement, and evaluative outcomes.

    PubMed

    Macias, Cathaleene; Barreira, Paul; Hargreaves, William; Bickman, Leonard; Fisher, William; Aronson, Elliot

    2005-04-01

    The inability to blind research participants to their experimental conditions is the Achilles' heel of mental health services research. When one experimental condition receives more disappointed participants, or more satisfied participants, research findings can be biased in spite of random assignment. The authors explored the potential for research participants' preference for one experimental program over another to compromise the generalizability and validity of randomized controlled service evaluations as well as cross-study comparisons. Three Cox regression analyses measured the impact of applicants' service assignment preference on research project enrollment, engagement in assigned services, and a service-related outcome, competitive employment. A stated service preference, referral by an agency with a low level of continuity in outpatient care, and willingness to switch from current services were significant positive predictors of research enrollment. Match to service assignment preference was a significant positive predictor of service engagement, and mismatch to assignment preference was a significant negative predictor of both service engagement and employment outcome. Referral source type and service assignment preference should be routinely measured and statistically controlled for in all studies of mental health service effectiveness to provide a sound empirical base for evidence-based practice.

  13. Free radicals and antioxidant enzymes in older adults after regular senior elastic band exercising: an experimental randomized controlled pilot study.

    PubMed

    Liao, Lin Yu; Chung, Wei Sheng; Chen, Kuei Min

    2017-01-01

    The aim of this study was to pilot test the effects of regular senior elastic band exercises on the generation of free radicals and antioxidant enzyme activities in older adults. Long-term regular exercises have positive health promotion outcomes. On the contrary, high-intensity, high-speed and short-term exercises in older adults may increase free radicals and cause chronic disease and ageing effect. A prospective randomized controlled pilot study. Data were collected during 2012. Twenty-five older adults were recruited from a community care centre, southern Taiwan and were randomly assigned to either an experimental or control group. Twenty-two participants completed the study: experimental group (n = 10) and control group (n = 12). The experimental group performed 6-month senior elastic band exercises while the control group kept regular daily routines. Both groups received blood tests (thiobarbituric acid-reacting substances and glutathione peroxidase) 30 minutes before the study began and 1 hour after the final intervention treatment. At the end of the 6-month senior elastic band exercises, no statistically significant differences in thiobarbituric acid-reacting substances and glutathione peroxidase values between the experimental and control groups. No significant differences existed in both thiobarbituric acid-reacting substances and glutathione peroxidase values before and after the 6-month senior elastic band exercises either. Regular senior elastic band exercises did not increase the generation of free radicals and antioxidant enzyme activities. Senior elastic band exercises have the potential to be promoted among older adults in the community as an exercise option without adverse effects on free radicals and have potential for mitigating ageing and increasing disease control. © 2016 John Wiley & Sons Ltd.

  14. Effect of cryotherapy on arteriovenous fistula puncture-related pain in hemodialysis patients.

    PubMed

    P B, Sabitha; Khakha, D C; Mahajan, S; Gupta, S; Agarwal, M; Yadav, S L

    2008-10-01

    Pain during areteriovenous fistula (AVF) cannulation remains a common problem in hemodialysis (HD) patients. This study was undertaken to assess the effect of cryotherapy on pain due to arteriovenous fistula puncture in hemodialysis patients. A convenience sample of 60 patients (30 each in experimental and control groups) who were undergoing hemodialysis by using AVF, was assessed in a randomized control trial. Hemodialysis patients who met the inclusion criteria, were randomly assigned to experimental and control groups using a randomization table. Objective and subjective pain scoring was done on two consecutive days of HD treatment (with cryotherapy for the experimental and without cryotherapy for the control group). The tools used were a questionnaire examining demographic and clinical characteristics, an observation checklist for assessing objective pain behavior, and a numerical rating scale for subjective pain assessment. Descriptive statistics were used as deemed appropriate. Chi square, two-sample and paired t-tests, the Mann Whitney test, Wilcoxon's signed rank test, the Kruskal Wallis test, and Spearman's and Pearson's correlations were used for inferential statistics. We found that the objective and subjective pain scores were found to be significantly (P = 0.001) reduced within the experimental group with the application of cryotherapy. This study highlights the need for adopting alternative therapies such as cryotherapy for effective pain management in hospital settings.

  15. What's in a Trial? On the Importance of Distinguishing Between Experimental Lab Studies and Randomized Controlled Trials: The Case of Cognitive Bias Modification and Alcohol Use Disorders.

    PubMed

    Wiers, Reinout W; Boffo, Marilisa; Field, Matt

    2018-05-01

    Recently, the National Institutes of Health (NIH) redefined clinical trials to include any study involving behavioral or biomedical interventions. In line with a general framework from experimental medicine, we argue that it is crucial to distinguish between experimental laboratory studies aimed at revealing psychological mechanisms underlying behavior and randomized controlled trials (RCTs) in clinical samples aimed at testing the efficacy of an intervention. As an illustration, we reviewed the current state of the evidence on the efficacy of cognitive bias modification (CBM) interventions in alcohol use disorders. A recent meta-analysis "cast serious doubts on the clinical utility of CBM interventions for addiction." That analysis combined experimental laboratory studies and RCTs. We demonstrated that, when studies are differentiated regarding study type (experimental laboratory study or RCT), mode of delivery (controlled experiment or Internet), and population (healthy volunteers or patients), the following effects are found: (a) short-lived effects of CBM on drinking behavior in experimental laboratory studies in students, but only when the bias is successfully manipulated; (b) small but robust effects of CBM on treatment outcome when administered as an adjunct to established treatments in clinical settings in RCTs with alcohol-dependent patients; and (c) nonspecific effects (reduced drinking irrespective of condition) in RCTs of CBM administered online to problem drinkers. We discuss how CBM might be improved when it is better integrated into regular treatment, especially cognitive behavioral therapy, and we conclude that disregarding the difference between experimental laboratory studies and RCTs can lead to invalid conclusions.

  16. Object Recognition and Random Image Structure Evolution

    ERIC Educational Resources Information Center

    Sadr, Jvid; Sinha, Pawan

    2004-01-01

    We present a technique called Random Image Structure Evolution (RISE) for use in experimental investigations of high-level visual perception. Potential applications of RISE include the quantitative measurement of perceptual hysteresis and priming, the study of the neural substrates of object perception, and the assessment and detection of subtle…

  17. Flux control coefficients determined by inhibitor titration: the design and analysis of experiments to minimize errors.

    PubMed Central

    Small, J R

    1993-01-01

    This paper is a study into the effects of experimental error on the estimated values of flux control coefficients obtained using specific inhibitors. Two possible techniques for analysing the experimental data are compared: a simple extrapolation method (the so-called graph method) and a non-linear function fitting method. For these techniques, the sources of systematic errors are identified and the effects of systematic and random errors are quantified, using both statistical analysis and numerical computation. It is shown that the graph method is very sensitive to random errors and, under all conditions studied, that the fitting method, even under conditions where the assumptions underlying the fitted function do not hold, outperformed the graph method. Possible ways of designing experiments to minimize the effects of experimental errors are analysed and discussed. PMID:8257434

  18. Computer Assisted English Language Learning in Costa Rican Elementary Schools: An Experimental Study

    ERIC Educational Resources Information Center

    Alvarez-Marinelli, Horacio; Blanco, Marta; Lara-Alecio, Rafael; Irby, Beverly J.; Tong, Fuhui; Stanley, Katherine; Fan, Yinan

    2016-01-01

    This study presents first-year findings of a 25-week longitudinal project derived from a two-year longitudinal randomized trial study at the elementary school level in Costa Rica on effective computer-assisted language learning (CALL) approaches in an English as a foreign language (EFL) setting. A pre-test-post-test experimental group design was…

  19. Optical Interactions at Randomly Rough Surfaces

    DTIC Science & Technology

    2003-03-10

    frequency range. The design of a random surface that acts as a Lambertian diffuser, especially in the infrared region of the optical spectrum, is...FTIR grazing angle microscopy. Recently, an experimental study was performed of the far-field scattering at small grazing angles, especially the enhanced...a specular component in the scattered light, in this frequency range. The design of a random surface that acts as a Lambertian diffuser, especially in

  20. Experimental analysis of the flow near the boundary of random porous media

    NASA Astrophysics Data System (ADS)

    Wu, Zhenxing; Mirbod, Parisa

    2018-04-01

    The aim of this work is to experimentally examine flow over and near random porous media. Different porous materials were chosen to achieve porosity ranging from 0.95 to 0.99. In this study, we report the detailed velocity measurements of the flow over and near random porous material inside a rectangular duct using a planar particle image velocimetry (PIV) technique. By controlling the flow rate, two different Reynolds numbers were achieved. We determined the slip velocity at the interface between the porous media and free flow. Values of the slip velocity normalized either by the maximum flow velocity or by the shear rate at the interface and the screening distance K1/2 were found to depend on porosity. It was also shown that the depth of penetration inside the porous material was larger than the screening length using Brinkman's prediction. Moreover, we examined a model for the laminar coupled flow over and inside porous media and analyzed the permeability of a random porous medium. This study provided detailed analysis of flow over and at the interface of various specific random porous media using the PIV technique. This analysis has the potential to serve as a first step toward using random porous media as a new passive technique to control the flow over smooth surfaces.

  1. An Investigation of Effectiveness of Conceptual Change Text-oriented Instruction on Students' Understanding of Solution Concepts

    NASA Astrophysics Data System (ADS)

    Pinarbaşi; , Tacettin; Canpolat, Nurtaç; Bayrakçeken, Samih; Geban, Ömer

    2006-12-01

    This study investigated the effect of conceptual change text-oriented instruction over traditional instruction on students' understanding of solution concepts (e.g., dissolving, solubility, factors affecting solubility, concentrations of solutions, types of solutions, physical properties of solutions) and their attitudes towards chemistry. The sample of this study consisted of 87 undergraduate students from two classes enrolled in an introductory chemistry course. One of the classes was assigned randomly to the control group, and the other class were assigned randomly to the experimental group. During teaching the topic of solution concepts in the chemistry curriculum, a conceptual change text-oriented instruction was applied in the experimental group whereas traditional instruction was followed in the control group. The results showed that the students in the experimental group performed better with respect to solution concepts. In addition, it has been found that there was no significant difference between the attitudes of students in the experimental and control groups towards chemistry.

  2. A minimal-contact intervention for cardiac inpatients: long-term effects on smoking cessation.

    PubMed

    Bolman, Catherine; de Vries, Hein; van Breukelen, Gerard

    2002-08-01

    This study examined the 1-year effects of a minimal-contact smoking cessation intervention for cardiac inpatients. The multicenter study included cardiac inpatients who had smoked prior to hospitalization. A pretest-posttest quasi-experimental design was used. Patients' experimental condition depended on the hospital they were assigned to. The design was partially randomized: 4 of the 11 hospitals selected the experimental condition themselves (2 experimental, 2 control), while the remaining 7 hospitals were randomly assigned. The experimental group consisted of patients of 5 hospitals (N = 388). Patients of 6 other hospitals served as the control group (N = 401). The intervention included stop-smoking advice by the cardiologist, brief counseling by the nurse, the provision of self-help materials, and aftercare by the cardiologist. Logistic regression analyses controlling for baseline differences and covariates did not show significant intervention effects on point prevalence and continuous abstinence. The study also showed that the outcomes were not significantly related to the way hospitals were assigned to the experimental condition. While short-term effects were found, the minimal-contact intervention did not result in significant effects after 12 months, at least if patients lost to follow-up were treated as posttest smokers. Efforts should be made to improve the intervention, especially the aftercare.

  3. Randomization Does Not Help Much, Comparability Does

    PubMed Central

    Saint-Mont, Uwe

    2015-01-01

    According to R.A. Fisher, randomization “relieves the experimenter from the anxiety of considering innumerable causes by which the data may be disturbed.” Since, in particular, it is said to control for known and unknown nuisance factors that may considerably challenge the validity of a result, it has become very popular. This contribution challenges the received view. First, looking for quantitative support, we study a number of straightforward, mathematically simple models. They all demonstrate that the optimism surrounding randomization is questionable: In small to medium-sized samples, random allocation of units to treatments typically yields a considerable imbalance between the groups, i.e., confounding due to randomization is the rule rather than the exception. In the second part of this contribution, the reasoning is extended to a number of traditional arguments in favour of randomization. This discussion is rather non-technical, and sometimes touches on the rather fundamental Frequentist/Bayesian debate. However, the result of this analysis turns out to be quite similar: While the contribution of randomization remains doubtful, comparability contributes much to a compelling conclusion. Summing up, classical experimentation based on sound background theory and the systematic construction of exchangeable groups seems to be advisable. PMID:26193621

  4. Effect of a toothpaste containing triclosan, cetylpyridinium chloride, and essential oils on gingival status in schoolchildren: a randomized clinical pilot study.

    PubMed

    Cagetti, Maria Grazia; Strohmenger, Laura; Basile, Valentina; Abati, Silvio; Mastroberardino, Stefano; Campus, Guglielmo

    2015-05-01

    This randomized double-blind in vivo pilot study has evaluated the effects of a toothpaste containing fluoride (control) versus toothpaste containing fluoride, triclosan, cetylpyridinium chloride and essential oils (experimental) in controlling supragingival dental plaque and bleeding on probing in a sample of healthy schoolchildren. In total, 48 children (8 to 10 years) were selected and randomly divided into two groups (experimental and control), using the two different toothpastes twice a day for 2 minutes each for a 4-week period. The investigation included an evaluation of plaque quantity, using the Turesky modified Quigley-Hein method, and bleeding on probing that was recorded dichotomously. The unit of analysis was set at the gingival site level. Plaque Index and bleeding on probing were analyzed using distribution tables and chi-square test. A generalized estimating equation was used to estimate the parameters of a generalized linear model with a possible unknown correlation between outcomes. In total, 40 schoolchildren completed the trial. Considering each group separately, a statistically significant difference in plaque scores was recorded for both treatments (z-test = 9.23, P < .01 for the experimental toothpaste; and z-test = 7.47, P < .01 for the control toothpaste). Nevertheless, the effect over time was higher for the experimental toothpaste than for the control one (3.38 vs 1.96). No statistically significant results were observed regarding bleeding on probing. The 4-week use of the experimental toothpaste seems to produce higher plaque reduction compared to fluoridated toothpaste without other antibacterial ingredients. This finding has to be confirmed in a larger study.

  5. An Experimental Evaluation of a School-Based Emancipatory Intervention to Promote African American Well-Being and Youth Leadership

    ERIC Educational Resources Information Center

    Lewis, Kelly M.; Sullivan, Cris M.; Bybee, Deborah

    2006-01-01

    This study experimentally examined the effect of a school-based emancipatory intervention on the psychological and behavioral well-being of African American adolescents. Sixty-five eighth graders in an inner-city, predominantly Black school were randomly assigned to either receive the experimental intervention or a regular Life Skills course (the…

  6. Using Advance Organizers to Enhance Pupils' Achievement in Learning Poetry in English Language

    ERIC Educational Resources Information Center

    Muiruri, Mary; Wambugu, Patriciah; Wamukuru, Kuria

    2016-01-01

    The study was a quasi-experimental that investigated the effects of Advance Organizers (AO) on achievement in poetry. Target population was class seven pupils of Nakuru North Sub-county primary schools in Kenya. 160 pupils were involved in the study. Four sampled schools were randomly assigned to control and experimental groups in Solomon Four…

  7. An Experimental Study Comparing English-Only and Transitional Bilingual Education on Spanish-Speaking Preschoolers' Early Literacy Development

    ERIC Educational Resources Information Center

    Duran, Lillian K.; Roseth, Cary J.; Hoffman, Patricia

    2010-01-01

    A longitudinal, experimental-control design was used to test the hypothesis that native language instruction enhances English language learner's (ELL's) native language and literacy development without significant cost to English development. In this study, 31 Spanish-speaking preschoolers (aged 38-48 months) were randomly assigned to two Head…

  8. The Impact of Concept Mapping on EFL Learners' Critical Thinking Ability

    ERIC Educational Resources Information Center

    Khodadady, Ebrahim; Ghanizadeh, Afsaneh

    2011-01-01

    The present study investigated the influence of concept mapping as a post-reading strategy on EFL learners' critical thinking ability. The study utilized a pretest-posttest control and experimental group design. To do so, thirty six EFL learners at upper intermediate and advanced levels were randomly assigned to experimental (n=18) and control…

  9. Cross-Age Peer Tutors in Asynchronous Discussion Groups: Studying the Impact of Tutors Labelling Their Interventions

    ERIC Educational Resources Information Center

    De Smet, M.; Van Keer, H.; Valcke, M.

    2008-01-01

    Cross-age tutors were randomly assigned to one of the three tutor training conditions distinguished for the current study: (1) the labelling experimental condition, characterized by requirements to label their tutor interventions, based on the e-moderating model of Salmon; (2) the non-labelling experimental condition, focusing on tutor's acting…

  10. Systematic versus random sampling in stereological studies.

    PubMed

    West, Mark J

    2012-12-01

    The sampling that takes place at all levels of an experimental design must be random if the estimate is to be unbiased in a statistical sense. There are two fundamental ways by which one can make a random sample of the sections and positions to be probed on the sections. Using a card-sampling analogy, one can pick any card at all out of a deck of cards. This is referred to as independent random sampling because the sampling of any one card is made without reference to the position of the other cards. The other approach to obtaining a random sample would be to pick a card within a set number of cards and others at equal intervals within the deck. Systematic sampling along one axis of many biological structures is more efficient than random sampling, because most biological structures are not randomly organized. This article discusses the merits of systematic versus random sampling in stereological studies.

  11. A dual-docking microfluidic cell migration assay (D2-Chip) for testing neutrophil chemotaxis and the memory effect.

    PubMed

    Yang, Ke; Wu, Jiandong; Xu, Guoqing; Xie, Dongxue; Peretz-Soroka, Hagit; Santos, Susy; Alexander, Murray; Zhu, Ling; Zhang, Michael; Liu, Yong; Lin, Francis

    2017-04-18

    Chemotaxis is a classic mechanism for guiding cell migration and an important topic in both fundamental cell biology and health sciences. Neutrophils are a widely used model to study eukaryotic cell migration and neutrophil chemotaxis itself can lead to protective or harmful immune actions to the body. While much has been learnt from past research about how neutrophils effectively navigate through a chemoattractant gradient, many interesting questions remain unclear. For example, while it is tempting to model neutrophil chemotaxis using the well-established biased random walk theory, the experimental proof was challenged by the cell's highly persistent migrating nature. A special experimental design is required to test the key predictions from the random walk model. Another question that has interested the cell migration community for decades concerns the existence of chemotactic memory and its underlying mechanism. Although chemotactic memory has been suggested in various studies, a clear quantitative experimental demonstration will improve our understanding of the migratory memory effect. Motivated by these questions, we developed a microfluidic cell migration assay (so-called dual-docking chip or D 2 -Chip) that can test both the biased random walk model and the memory effect for neutrophil chemotaxis on a single chip enabled by multi-region gradient generation and dual-region cell alignment. Our results provide experimental support for the biased random walk model and chemotactic memory for neutrophil chemotaxis. Quantitative data analyses provide new insights into neutrophil chemotaxis and memory by making connections to entropic disorder, cell morphology and oscillating migratory response.

  12. Preference in Random Assignment: Implications for the Interpretation of Randomized Trials

    PubMed Central

    Gold, Paul B.; Hargreaves, William A.; Aronson, Elliot; Bickman, Leonard; Barreira, Paul J.; Jones, Danson R.; Rodican, Charles F.; Fisher, William H.

    2009-01-01

    Random assignment to a preferred experimental condition can increase service engagement and enhance outcomes, while assignment to a less-preferred condition can discourage service receipt and limit outcome attainment. We examined randomized trials for one prominent psychiatric rehabilitation intervention, supported employment, to gauge how often assignment preference might have complicated the interpretation of findings. Condition descriptions, and greater early attrition from services-as-usual comparison conditions, suggest that many study enrollees favored assignment to new rapid-job-placement supported employment, but no study took this possibility into account. Reviews of trials in other service fields are needed to determine whether this design problem is widespread. PMID:19434489

  13. Warm-up for Sprint Swimming: Race-Pace or Aerobic Stimulation? A Randomized Study.

    PubMed

    Neiva, Henrique P; Marques, Mário C; Barbosa, Tiago M; Izquierdo, Mikel; Viana, João L; Teixeira, Ana M; Marinho, Daniel A

    2017-09-01

    Neiva, HP, Marques, MC, Barbosa, TM, Izquierdo, M, Viana, JL, Teixeira, AM, and Marinho, DA. Warm-up for sprint swimming: race-pace or aerobic stimulation? A randomized study. J Strength Cond Res 31(9): 2423-2431, 2017-The aim of this study was to compare the effects of 2 different warm-up intensities on 100-m swimming performance in a randomized controlled trial. Thirteen competitive swimmers performed two 100-m freestyle time-trials on separate days after either control or experimental warm-up in a randomized design. The control warm-up included a typical race-pace set (4 × 25 m), whereas the experimental warm-up included an aerobic set (8 × 50 m at 98-102% of critical velocity). Cortisol, testosterone, blood lactate ([La]), oxygen uptake (V[Combining Dot Above]O2), heart rate, core (Tcore and Tcorenet) and tympanic temperatures, and rating of perceived exertion (RPE) were monitored. Stroke length (SL), stroke frequency (SF), stroke index (SI), and propelling efficiency (ηp) were assessed for each 50-m lap. We found that V[Combining Dot Above]O2, heart rate, and Tcorenet were higher after experimental warm-up (d > 0.73), but only the positive effect for Tcorenet was maintained until the trial. Performance was not different between conditions (d = 0.07). Experimental warm-up was found to slow SF (mean change ±90% CL = 2.06 ± 1.48%) and increase SL (1.65 ± 1.40%) and ηp (1.87 ± 1.33%) in the first lap. After the time-trials, this warm-up had a positive effect on Tcorenet (d = 0.69) and a negative effect on [La] (d = 0.56). Although the warm-ups had similar outcomes in the 100-m freestyle, performance was achieved through different biomechanical strategies. Stroke length and efficiency were higher in the first lap after the experimental warm-up, whereas SF was higher after control warm-up. Physiological adaptations were observed mainly through an increased Tcore after experimental warm-up. In this condition, the lower [La] after the trial suggests lower dependency on anaerobic metabolism.

  14. Evaluation of a School-Based Teen Obesity Prevention Minimal Intervention

    ERIC Educational Resources Information Center

    Abood, Doris A.; Black, David R.; Coster, Daniel C.

    2008-01-01

    Objective: A school-based nutrition education minimal intervention (MI) was evaluated. Design: The design was experimental, with random assignment at the school level. Setting: Seven schools were randomly assigned as experimental, and 7 as delayed-treatment. Participants: The experimental group included 551 teens, and the delayed treatment group…

  15. The Implications of "Contamination" for Experimental Design in Education

    ERIC Educational Resources Information Center

    Rhoads, Christopher H.

    2011-01-01

    Experimental designs that randomly assign entire clusters of individuals (e.g., schools and classrooms) to treatments are frequently advocated as a way of guarding against contamination of the estimated average causal effect of treatment. However, in the absence of contamination, experimental designs that randomly assign intact clusters to…

  16. Impulsive lifestyle counseling to prevent dropout from treatment for substance use disorders in people with antisocial personality disorder: A randomized study.

    PubMed

    Thylstrup, Birgitte; Hesse, Morten

    2016-06-01

    Patients with antisocial personality disorder in outpatient treatment for substance use disorders are at high risk of drop-out. Using a randomized design, this study tested the impact of adding a brief psycho-educational program, the Impulsive Lifestyle Counseling program, to outpatient substance abuse treatment in order to prevent treatment dropout. Patients (N=175) were recruited from 13 municipal treatment centers in Denmark, and assigned to treatment as usual or to the experimental condition. In all, 172 patients could be included in the analyses. In the intent-to-treat analysis, the risk of treatment dropout was reduced among patients randomized to the experimental program (hazard ratio=0.63, p=.031), after controlling for age, gender, and substitution treatment status. The study supported the efficacy of the Impulsive Lifestyle Counseling program as a method for preventing treatment dropout for patients with comorbid antisocial personality disorder in substance abuse treatment. Trial registration #ISRCTN67266318. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Effects of Teaching a Library Usage Unit to Seventh Graders.

    ERIC Educational Resources Information Center

    Gifford, Vernon; Gifford, Jean

    This document reports the results of a study undertaken to determine if teaching a 2-week unit on library usage to 7th graders would increase their use of the library. From three non-ability grouped 7th grade classes, two classes of 26 students each were randomly selected for the study. One class was randomly assigned as the experimental group and…

  18. On-line failure detection and damping measurement of aerospace structures by random decrement signatures

    NASA Technical Reports Server (NTRS)

    Cole, H. A., Jr.

    1973-01-01

    Random decrement signatures of structures vibrating in a random environment are studied through use of computer-generated and experimental data. Statistical properties obtained indicate that these signatures are stable in form and scale and hence, should have wide application in one-line failure detection and damping measurement. On-line procedures are described and equations for estimating record-length requirements to obtain signatures of a prescribed precision are given.

  19. Entre Dos Mundos/Between Two Worlds: Youth Violence Prevention for Acculturating Latino Families

    ERIC Educational Resources Information Center

    Smokowski, Paul R.; Bacallao, Martica

    2009-01-01

    Objective: This study evaluated the efficacy of Entre Dos Mundos/Between Two Worlds (EDM) prevention for Latino adolescents. Method: In an experimental trial to compare implementation formats, 41 Latino families were randomly assigned to EDM action-oriented skills training groups, and 47 families were randomly assigned to unstructured EDM support…

  20. The Effect of Diffused Aromatherapy on Test Anxiety among Baccalaureate Nursing Students

    ERIC Educational Resources Information Center

    Johnson, Catherine E.

    2013-01-01

    A quantitative, randomized, pretest, posttest study was conducted to assess the effect of aromatherapy on cognitive test anxiety among nursing students. Sophomore nursing students (n = 39) from a private, 4-year college, were randomized into either the control group (n = 18) or the experimental group (n = 21). Each participant completed the…

  1. Driving with Intuition: A Preregistered Study about the EEG Anticipation of Simulated Random Car Accidents

    PubMed Central

    Duma, Gian Marco; Mento, Giovanni; Manari, Tommaso; Martinelli, Massimiliano

    2017-01-01

    The study of neural pre-stimulus or “anticipatory” activity opened a new window for understanding how the brain actively constructs the forthcoming reality. Usually, experimental paradigms designed to study anticipatory activity make use of stimuli. The purpose of the present study is to expand the study of neural anticipatory activity upon the temporal occurrence of dichotomic, statistically unpredictable (random) stimuli within an ecological experimental paradigm. To this purpose, we used a simplified driving simulation including two possible, randomly-presented trial types: a car crash end trial and a no car crash end trial. Event Related Potentials (ERP) were extracted -3,000 ms before stimulus onset. We identified a fronto-central negativity starting around 1,000 ms before car crash presentation. By contrast, a whole-scalp distributed positivity characterized the anticipatory activity observed before the end of the trial in the no car crash end condition. The present data are in line with the hypothesis that the brain may also anticipate dichotomic, statistically unpredictable stimuli, relaying onto different pre-stimulus ERP activity. Possible integration with car-smart-systems is also suggested. PMID:28103303

  2. Experimental vibroacoustic testing of plane panels using synthesized random pressure fields.

    PubMed

    Robin, Olivier; Berry, Alain; Moreau, Stéphane

    2014-06-01

    The experimental reproduction of random pressure fields on a plane panel and corresponding induced vibrations is studied. An open-loop reproduction strategy is proposed that uses the synthetic array concept, for which a small array element is moved to create a large array by post-processing. Three possible approaches are suggested to define the complex amplitudes to be imposed to the reproduction sources distributed on a virtual plane facing the panel to be tested. Using a single acoustic monopole, a scanning laser vibrometer and a baffled simply supported aluminum panel, experimental vibroacoustic indicators such as the Transmission Loss for Diffuse Acoustic Field, high-speed subsonic and supersonic Turbulent Boundary Layer excitations are obtained. Comparisons with simulation results obtained using a commercial software show that the Transmission Loss estimation is possible under both excitations. Moreover and as a complement to frequency domain indicators, the vibroacoustic behavior of the panel can be studied in the wave number domain.

  3. R. A. Fisher and his advocacy of randomization.

    PubMed

    Hall, Nancy S

    2007-01-01

    The requirement of randomization in experimental design was first stated by R. A. Fisher, statistician and geneticist, in 1925 in his book Statistical Methods for Research Workers. Earlier designs were systematic and involved the judgment of the experimenter; this led to possible bias and inaccurate interpretation of the data. Fisher's dictum was that randomization eliminates bias and permits a valid test of significance. Randomization in experimenting had been used by Charles Sanders Peirce in 1885 but the practice was not continued. Fisher developed his concepts of randomizing as he considered the mathematics of small samples, in discussions with "Student," William Sealy Gosset. Fisher published extensively. His principles of experimental design were spread worldwide by the many "voluntary workers" who came from other institutions to Rothamsted Agricultural Station in England to learn Fisher's methods.

  4. Study of Teaching Residents How to Teach.

    ERIC Educational Resources Information Center

    Edwards, Janine C.; And Others

    1988-01-01

    The effectiveness of a teaching skills program for residents at Louisiana State University Medical Center was evaluated among 22 residents in obstetrics and gynecology, medicine, and family medicine who were randomly assigned to control and experimental groups. There was greater increase in the scores of the experimental than the control groups.…

  5. Effects of Critical Discussions on Middle School Students' Written Historical Arguments

    ERIC Educational Resources Information Center

    Wissinger, Daniel R.; De La Paz, Susan

    2016-01-01

    In this experimental study, 151 middle school students explored 3 historical controversies, first reading and discussing primary source documents in groups, then writing arguments on their own. Students were either randomly assigned to an experimental condition, using argumentative schemes and critical questions as guides during discussions, or to…

  6. Inquiry in the Physical Geology Classroom: Supporting Students' Conceptual Model Development

    ERIC Educational Resources Information Center

    Miller, Heather R.; McNeal, Karen S.; Herbert, Bruce E.

    2010-01-01

    This study characterizes the impact of an inquiry-based learning (IBL) module versus a traditionally structured laboratory exercise. Laboratory sections were randomized into experimental and control groups. The experimental group was taught using IBL pedagogical techniques and included manipulation of large-scale data-sets, use of multiple…

  7. Capturing Students' Attention: An Empirical Study

    ERIC Educational Resources Information Center

    Rosegard, Erik; Wilson, Jackson

    2013-01-01

    College students ("n" = 846) enrolled in a general education course were randomly assigned to either an arousal (experimental) or no-arousal (control) group. The experimental group was exposed to a topic-relevant, 90-second external stimulus (a technique used to elevate arousal and focus attention). The control group listened to the…

  8. Evaluation of the Better Parenting Programme in Jordan

    ERIC Educational Resources Information Center

    Al-Hassan, Suha M.; Lansford, Jennifer E.

    2011-01-01

    This study evaluates the Better Parenting Programme (BPP) which has been implemented nationally in Jordan to enhance parents' knowledge, attitudes, and behaviours related to caring for young children. The participants (N = 337, 94% female) were randomly assigned to an experimental group or a control group. The experimental group participated in…

  9. Snoezelen Room and Childbirth Outcome: A Randomized Clinical Trial.

    PubMed

    Jamshidi Manesh, Mansoureh; Kalati, Mahnaz; Hosseini, Fatemeh

    2015-05-01

    One of the strategies for a good outcome and pain free childbearing is to design the delivery room. The aim of this study was to evaluate the effects of snoezelen room on childbearing outcome such as pain intensity, duration of labor, and perinea status in nulliparous women. This study was a randomized controlled clinical trial consists of 100 childbearing women. They were randomly divided into 2 groups. The experimental group went to snoezelen room when their cervix dilation was 4 cm, while the control group went to physiologic delivery room with the same cervix dilation. The mean ± SD of VAS (Visual Analogue Scale) pain intensity of the experimental and control groups before the intervention were 5.1 ± 1.95 and 5.58 ± 1.62, respectively (P = 0.13). The mean ± SD of VAS pain intensity scores of the experimental and control groups after 3 hours spending in their assigned rooms were 5.26 ± 0.86 and 9.56 ± 1.48, respectively (P = 0.01). The mean ± SD of the first stage scores of the experimental and control groups were 6.95 ± 0.97 and 8.41 ± 0.67, respectively (P = 0.042). About 92% of participants' intervention vs. 66% of control participants had perinea laceration (P = 0.041). According to the findings of the present study, distracting senses in snoezelen room decreases mother's pain intensity, the length of labor, and incidence of episiotomy.

  10. Snoezelen Room and Childbirth Outcome: A Randomized Clinical Trial

    PubMed Central

    Jamshidi Manesh, Mansoureh; Kalati, Mahnaz; Hosseini, Fatemeh

    2015-01-01

    Background: One of the strategies for a good outcome and pain free childbearing is to design the delivery room. Objectives: The aim of this study was to evaluate the effects of snoezelen room on childbearing outcome such as pain intensity, duration of labor, and perinea status in nulliparous women. Patients and Methods: This study was a randomized controlled clinical trial consists of 100 childbearing women. They were randomly divided into 2 groups. The experimental group went to snoezelen room when their cervix dilation was 4 cm, while the control group went to physiologic delivery room with the same cervix dilation. Results: The mean ± SD of VAS (Visual Analogue Scale) pain intensity of the experimental and control groups before the intervention were 5.1 ± 1.95 and 5.58 ± 1.62, respectively (P = 0.13). The mean ± SD of VAS pain intensity scores of the experimental and control groups after 3 hours spending in their assigned rooms were 5.26 ± 0.86 and 9.56 ± 1.48, respectively (P = 0.01). The mean ± SD of the first stage scores of the experimental and control groups were 6.95 ± 0.97 and 8.41 ± 0.67, respectively (P = 0.042). About 92% of participants’ intervention vs. 66% of control participants had perinea laceration (P = 0.041). Conclusions: According to the findings of the present study, distracting senses in snoezelen room decreases mother’s pain intensity, the length of labor, and incidence of episiotomy. PMID:26082849

  11. Effect of random surface inhomogeneities on spectral properties of dielectric-disk microresonators: theory and modeling at millimeter wave range.

    PubMed

    Ganapolskii, E M; Eremenko, Z E; Tarasov, Yu V

    2009-04-01

    The influence of random axially homogeneous surface roughness on spectral properties of dielectric resonators of circular disk form is studied both theoretically and experimentally. To solve the equations governing the dynamics of electromagnetic fields, the method of eigenmode separation is applied previously developed with reference to inhomogeneous systems subject to arbitrary external static potential. We prove theoretically that it is the gradient mechanism of wave-surface scattering that is highly responsible for nondissipative loss in the resonator. The influence of side-boundary inhomogeneities on the resonator spectrum is shown to be described in terms of effective renormalization of mode wave numbers jointly with azimuth indices in the characteristic equation. To study experimentally the effect of inhomogeneities on the resonator spectrum, the method of modeling in the millimeter wave range is applied. As a model object, we use a dielectric disk resonator (DDR) fitted with external inhomogeneities randomly arranged at its side boundary. Experimental results show good agreement with theoretical predictions as regards the predominance of the gradient scattering mechanism. It is shown theoretically and confirmed in the experiment that TM oscillations in the DDR are less affected by surface inhomogeneities than TE oscillations with the same azimuth indices. The DDR model chosen for our study as well as characteristic equations obtained thereupon enable one to calculate both the eigenfrequencies and the Q factors of resonance spectral lines to fairly good accuracy. The results of calculations agree well with obtained experimental data.

  12. A randomized controlled trial of an intervention program to Brazilian mothers who use corporal punishment.

    PubMed

    Santini, Paolla Magioni; Williams, Lucia C A

    2017-09-01

    This study evaluated a positive parenting program to Brazilian mothers who used corporal punishment with their children. The intervention was conducted in four agencies serving vulnerable children, and at a home replica laboratory at the University. Mothers who admitted using corporal punishment were randomly assigned between experimental (n=20) and control group (n=20). The program consisted of 12 individual sessions using one unit from Projeto Parceria (Partnership Project), with specific guidelines and materials on positive parenting, followed by observational sessions of mother-child interaction with live coaching and a video feedback session in the lab. The study used an equivalent group experimental design with pre/post-test and follow-up, in randomized controlled trials. Measures involved: Initial Interview; Strengths and Difficulties Questionnaire (SDQ) - parent and child versions; Beck Depression Inventory (BDI); observational sessions with a protocol; and a Program Evaluation by participants. Analysis of mixed models for repeated measures revealed significant positive effects on the BDI and SDQ total scores, as well as less Conduct problems and Hyperactivity in SDQ measures from the experimental group mothers, comparing pre with post-test. Observational data also indicated significant improvement in positive interaction from the experimental group mothers at post-test, in comparison with controls. No significant results were found, however, in children's observational measures. Limitations of the study involved using a restricted sample, among others. Implications for future research are suggested. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Fluid dynamics during Random Positioning Machine micro-gravity experiments

    NASA Astrophysics Data System (ADS)

    Leguy, Carole A. D.; Delfos, René; Pourquie, Mathieu J. B. M.; Poelma, Christian; Westerweel, Jerry; van Loon, Jack J. W. A.

    2017-06-01

    A Random Positioning Machine (RPM) is a device used to study the role of gravity on biological systems. This is accomplished through continuous reorientation of the sample such that the net influence of gravity is randomized over time. The aim of this study is to predict fluid flow behavior during such RPM simulated microgravity studies, which may explain differences found between RPM and space flight experiments. An analytical solution is given for a cylinder as a model for an experimental container. Then, a dual-axis rotating frame is used to mimic the motion characteristics of an RPM with sinusoidal rotation frequencies of 0.2 Hz and 0.1 Hz while Particle Image Velocimetry is used to measure the velocity field inside a flask. To reproduce the same experiment numerically, a Direct Numerical Simulation model is used. The analytical model predicts that an increase in the Womersley number leads to higher shear stresses at the cylinder wall and decrease in fluid angular velocity inside the cylinder. The experimental results show that periodic single-axis rotation induces a fluid motion parallel to the wall and that a complex flow is observed for two-axis rotation with a maximum wall shear stress of 8.0 mPa (80 mdyne /cm2). The experimental and numerical results show that oscillatory motion inside an RPM induces flow motion that can, depending on the experimental samples, reduce the quality of the simulated microgravity. Thus, it is crucial to determine the appropriate oscillatory frequency of the axes to design biological experiments.

  14. Effect of Solution Focused Group Counseling for High School Students in Order to Struggle with School Burnout

    ERIC Educational Resources Information Center

    Ates, Bünyamin

    2016-01-01

    In this research, the effect of solution focused group counseling upon high school students struggling with school burnout was analyzed. The research was an experimental study in which a pre-test post-test control group random design was used, depending upon the real experimental model. The study group included 30 students that volunteered from…

  15. Impact of Referral Source and Study Applicants’ Preference for Randomly Assigned Service on Research Enrollment, Service Engagement, and Evaluative Outcomes

    PubMed Central

    Macias, Cathaleene; Barreira, Paul; Hargreaves, William; Bickman, Leonard; Fisher, William; Aronson, Elliot

    2009-01-01

    Objective The inability to blind research participants to their experimental conditions is the Achilles’ heel of mental health services research. When one experimental condition receives more disappointed participants, or more satisfied participants, research findings can be biased in spite of random assignment. The authors explored the potential for research participants’ preference for one experimental program over another to compromise the generalizability and validity of randomized controlled service evaluations as well as cross-study comparisons. Method Three Cox regression analyses measured the impact of applicants’ service assignment preference on research project enrollment, engagement in assigned services, and a service-related outcome, competitive employment. Results A stated service preference, referral by an agency with a low level of continuity in outpatient care, and willingness to switch from current services were significant positive predictors of research enrollment. Match to service assignment preference was a significant positive predictor of service engagement, and mismatch to assignment preference was a significant negative predictor of both service engagement and employment outcome. Conclusions Referral source type and service assignment preference should be routinely measured and statistically controlled for in all studies of mental health service effectiveness to provide a sound empirical base for evidence-based practice. PMID:15800153

  16. No Randomization? No Problem: Experimental Control and Random Assignment in Single Case Research

    ERIC Educational Resources Information Center

    Ledford, Jennifer R.

    2018-01-01

    Randomization of large number of participants to different treatment groups is often not a feasible or preferable way to answer questions of immediate interest to professional practice. Single case designs (SCDs) are a class of research designs that are experimental in nature but require only a few participants, all of whom receive the…

  17. Evaluation of the Efficiency of the Nursing Care Plan Applied Using NANDA, NOC, and NIC Linkages to Elderly Women with Incontinence Living in a Nursing Home: A Randomized Controlled Study.

    PubMed

    Gencbas, Dercan; Bebis, Hatice; Cicek, Hatice

    2017-05-30

    Evaluate the efficiency of the nursing care plan, applied with the use of NANDA-I, NOC, and NIC (NNN) linkages, for elderly women with incontinence who live in nursing homes. A randomized controlled experimental design was applied. NNN linkages were prepared and applied for 12 weeks in an experimental group. NOC scales were evaluated again for two groups. A 0.5 NOC point change targeted in all elderly in the experimental group were provided between pretest-posttest scores. The experimental group had higher life quality and lower incontinence severity/symptoms than the control group. It is important that NNN linkages effective for solving the problems are used in different groups and with larger samples to create further evidence linking NNN. © 2017 NANDA International, Inc.

  18. Experimental effects of exposure to pornography: the moderating effect of personality and mediating effect of sexual arousal.

    PubMed

    Hald, Gert Martin; Malamuth, Neil N

    2015-01-01

    Using a randomly selected community sample of 200 Danish young adult men and women in a randomized experimental design, the study investigated the effects of a personality trait (agreeableness), past pornography consumption, and experimental exposure to non-violent pornography on attitudes supporting violence against women (ASV). We found that lower levels of agreeableness and higher levels of past pornography consumption significantly predicted ASV. In addition, experimental exposure to pornography increased ASV but only among men low in agreeableness. This relationship was found to be significantly mediated by sexual arousal with sexual arousal referring to the subjective assessment of feeling sexually excited, ready for sexual activities, and/or bodily sensations associated with being sexually aroused. In underscoring the importance of individual differences, the results supported the hierarchical confluence model of sexual aggression and the media literature on affective engagement and priming effects.

  19. Endometrial Injury May Increase the Pregnancy Rate in Patients Undergoing Intrauterine Insemination: An Interventional Randomized Clinical Trial.

    PubMed

    Bahaa Eldin, Ahmed M; Abdelmaabud, Karim H; Laban, Mohamed; Hassanin, Alaa S; Tharwat, Ahmed A; Aly, Tarek R; Elbohoty, Ahmed E; Elsayed, Helmy M; Ibrahim, Ahmed M; Ibrahim, Mohammed E; Sabaa, Haitham M; Abdelrazik, Azza A; Abdelhady, Ibrahim

    2016-10-01

    This study aimed to investigate the effect of endometrial injury using Pipelle catheter in the follicular phase (cycle day 5, 6, or 7) of the stimulation cycle on pregnancy rates in patients undergoing intrauterine insemination. This prospective randomized controlled study was carried out in the Assisted Reproductive Technology Unit of Ain Shams University Maternity Hospital, Cairo, Egypt, from July 1, 2013 to August 31, 2015. Three hundred sixty women, 20 to 35 years of age, with patent fallopian tubes, mild male factor infertility, or unexplained infertility were recruited. Participants were allocated randomly into 2 groups: experimental arm and control arm. Women in the experimental arm underwent endometrial biopsy using a Pipelle catheter on day 5, 6, or 7 of the stimulation cycle combined with intrauterine insemination. Women in the control group underwent intrauterine insemination with no endometrial biopsy done. The primary outcomes were the clinical and chemical pregnancy rates. Data of 344 participants were statistically analyzed. The chemical pregnancy rate was 23.66% in the experimental arm and 10.85% in the control arm (P = .002). The clinical pregnancy rate was 18.93% in the experimental arm and 7.42% in the control arm (P = .003). Endometrial injury using a Pipelle catheter in the stimulation cycle may improve pregnancy rates in women undergoing intrauterine insemination. © The Author(s) 2016.

  20. Ab initio random structure searching of organic molecular solids: assessment and validation against experimental data.

    PubMed

    Zilka, Miri; Dudenko, Dmytro V; Hughes, Colan E; Williams, P Andrew; Sturniolo, Simone; Franks, W Trent; Pickard, Chris J; Yates, Jonathan R; Harris, Kenneth D M; Brown, Steven P

    2017-10-04

    This paper explores the capability of using the DFT-D ab initio random structure searching (AIRSS) method to generate crystal structures of organic molecular materials, focusing on a system (m-aminobenzoic acid; m-ABA) that is known from experimental studies to exhibit abundant polymorphism. Within the structural constraints selected for the AIRSS calculations (specifically, centrosymmetric structures with Z = 4 for zwitterionic m-ABA molecules), the method is shown to successfully generate the two known polymorphs of m-ABA (form III and form IV) that have these structural features. We highlight various issues that are encountered in comparing crystal structures generated by AIRSS to experimental powder X-ray diffraction (XRD) data and solid-state magic-angle spinning (MAS) NMR data, demonstrating successful fitting for some of the lowest energy structures from the AIRSS calculations against experimental low-temperature powder XRD data for known polymorphs of m-ABA, and showing that comparison of computed and experimental solid-state NMR parameters allows different hydrogen-bonding motifs to be discriminated.

  1. Effects of the Anger Coping Programme based on cognitive behavioural techniques on adolescents' anger, aggression and psychological symptoms.

    PubMed

    Avci, Dilek; Kelleci, Meral

    2016-04-01

    This study aimed to determine the effects of an Anger Coping Programme based on cognitive behavioural techniques on adolescents' anger, aggression and psychological symptoms. In this randomized controlled experimental study, 385 ninth-year high school students in Turkey were administered the State-Trait Anger Expression Inventory, the Aggression Scale and the Brief Symptom Inventory in 2011-2012. Of the 385 students, 62 who met the inclusion criteria were randomly assigned to experimental and control groups by gender and the scores they obtained from the scales. The students in the experimental group met 1 day a week for 1.5 h, and the study lasted 10 weeks. The scales were administered three times: before the programme was started, immediately after the programme was completed and 6 weeks later. The Anger Coping Programme was effective at reducing students' anger and aggression levels, and a range of psychological symptoms except for somatization. © 2015 John Wiley & Sons Australia, Ltd.

  2. Prevention of Recurrent Foot Ulcers With Plantar Pressure–Based In-Shoe Orthoses: The CareFUL Prevention Multicenter Randomized Controlled Trial

    PubMed Central

    Ulbrecht, Jan S.; Hurley, Timothy; Mauger, David T.

    2014-01-01

    OBJECTIVE To assess the efficacy of in-shoe orthoses that were designed based on shape and barefoot plantar pressure in reducing the incidence of submetatarsal head plantar ulcers in people with diabetes, peripheral neuropathy, and a history of similar prior ulceration. RESEARCH DESIGN AND METHODS Single-blinded multicenter randomized controlled trial with subjects randomized to wear shape- and pressure-based orthoses (experimental, n = 66) or standard-of-care A5513 orthoses (control, n = 64). Patients were followed for 15 months, until a study end point (forefoot plantar ulcer or nonulcerative plantar forefoot lesion) or to study termination. Proportional hazards regression was used for analysis. RESULTS There was a trend in the composite primary end point (both ulcers and nonulcerative lesions) across the full follow-up period (P = 0.13) in favor of the experimental orthoses. This trend was due to a marked difference in ulcer occurrence (P = 0.007) but no difference in the rate of nonulcerative lesions (P = 0.76). At 180 days, the ulcer prevention effect of the experimental orthoses was already significant (P = 0.003) when compared with control, and the benefit of the experimental orthoses with respect to the composite end point was also significant (P = 0.042). The hazard ratio was 3.4 (95% CI 1.3–8.7) for the occurrence of a submetatarsal head plantar ulcer in the control compared with experimental arm over the duration of the study. CONCLUSIONS We conclude that shape- and barefoot plantar pressure–based orthoses were more effective in reducing submetatarsal head plantar ulcer recurrence than current standard-of-care orthoses, but they did not significantly reduce nonulcerative lesions. PMID:24760263

  3. Prevention of recurrent foot ulcers with plantar pressure-based in-shoe orthoses: the CareFUL prevention multicenter randomized controlled trial.

    PubMed

    Ulbrecht, Jan S; Hurley, Timothy; Mauger, David T; Cavanagh, Peter R

    2014-07-01

    To assess the efficacy of in-shoe orthoses that were designed based on shape and barefoot plantar pressure in reducing the incidence of submetatarsal head plantar ulcers in people with diabetes, peripheral neuropathy, and a history of similar prior ulceration. Single-blinded multicenter randomized controlled trial with subjects randomized to wear shape- and pressure-based orthoses (experimental, n = 66) or standard-of-care A5513 orthoses (control, n = 64). Patients were followed for 15 months, until a study end point (forefoot plantar ulcer or nonulcerative plantar forefoot lesion) or to study termination. Proportional hazards regression was used for analysis. There was a trend in the composite primary end point (both ulcers and nonulcerative lesions) across the full follow-up period (P = 0.13) in favor of the experimental orthoses. This trend was due to a marked difference in ulcer occurrence (P = 0.007) but no difference in the rate of nonulcerative lesions (P = 0.76). At 180 days, the ulcer prevention effect of the experimental orthoses was already significant (P = 0.003) when compared with control, and the benefit of the experimental orthoses with respect to the composite end point was also significant (P = 0.042). The hazard ratio was 3.4 (95% CI 1.3-8.7) for the occurrence of a submetatarsal head plantar ulcer in the control compared with experimental arm over the duration of the study. We conclude that shape- and barefoot plantar pressure-based orthoses were more effective in reducing submetatarsal head plantar ulcer recurrence than current standard-of-care orthoses, but they did not significantly reduce nonulcerative lesions. © 2014 by the American Diabetes Association.

  4. On the Reporting of Experimental and Control Therapies in Stroke Rehabilitation Trials: A Systematic Review.

    PubMed

    Lohse, Keith R; Pathania, Anupriya; Wegman, Rebecca; Boyd, Lara A; Lang, Catherine E

    2018-03-01

    To use the Centralized Open-Access Rehabilitation database for Stroke to explore reporting of both experimental and control interventions in randomized controlled trials for stroke rehabilitation (including upper and lower extremity therapies). The Centralized Open-Access Rehabilitation database for Stroke was created from a search of MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Cumulative Index of Nursing and Allied Health from the earliest available date to May 31, 2014. A total of 2892 titles were reduced to 514 that were screened by full text. This screening left 215 randomized controlled trials in the database (489 independent groups representing 12,847 patients). Using a mixture of qualitative and quantitative methods, we performed a text-based analysis of how the procedures of experimental and control therapies were described. Experimental and control groups were rated by 2 independent coders according to the Template for Intervention Description and Replication criteria. Linear mixed-effects regression with a random effect of study (groups nested within studies) showed that experimental groups had statistically more words in their procedures (mean, 271.8 words) than did control groups (mean, 154.8 words) (P<.001). Experimental groups had statistically more references in their procedures (mean, 1.60 references) than did control groups (mean, .82 references) (P<.001). Experimental groups also scored significantly higher on the total Template for Intervention Description and Replication checklist (mean score, 7.43 points) than did control groups (mean score, 5.23 points) (P<.001). Control treatments in stroke motor rehabilitation trials are underdescribed relative to experimental treatments. These poor descriptions are especially problematic for "conventional" therapy control groups. Poor reporting is a threat to the internal validity and generalizability of clinical trial results. We recommend authors use preregistered protocols and established reporting criteria to improve transparency. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Teaching experimental design.

    PubMed

    Fry, Derek J

    2014-01-01

    Awareness of poor design and published concerns over study quality stimulated the development of courses on experimental design intended to improve matters. This article describes some of the thinking behind these courses and how the topics can be presented in a variety of formats. The premises are that education in experimental design should be undertaken with an awareness of educational principles, of how adults learn, and of the particular topics in the subject that need emphasis. For those using laboratory animals, it should include ethical considerations, particularly severity issues, and accommodate learners not confident with mathematics. Basic principles, explanation of fully randomized, randomized block, and factorial designs, and discussion of how to size an experiment form the minimum set of topics. A problem-solving approach can help develop the skills of deciding what are correct experimental units and suitable controls in different experimental scenarios, identifying when an experiment has not been properly randomized or blinded, and selecting the most efficient design for particular experimental situations. Content, pace, and presentation should suit the audience and time available, and variety both within a presentation and in ways of interacting with those being taught is likely to be effective. Details are given of a three-day course based on these ideas, which has been rated informative, educational, and enjoyable, and can form a postgraduate module. It has oral presentations reinforced by group exercises and discussions based on realistic problems, and computer exercises which include some analysis. Other case studies consider a half-day format and a module for animal technicians. © The Author 2014. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  6. A randomized phase II study comparing paclitaxel-carboplatin-bevacizumab with or without nitroglycerin patches in patients with stage IV nonsquamous nonsmall-cell lung cancer: NVALT12 (NCT01171170)†.

    PubMed

    Dingemans, A-M C; Groen, H J M; Herder, G J M; Stigt, J A; Smit, E F; Bahce, I; Burgers, J A; van den Borne, B E E M; Biesma, B; Vincent, A; van der Noort, V; Aerts, J G

    2015-11-01

    Nitroglycerin (NTG) increases tumor blood flow and oxygenation by inhibiting hypoxia-inducible-factor (HIF)-1. A randomized phase II study has shown improved outcome when NTG patches were added to vinorelbine/cisplatin in patients with advanced nonsmall-cell lung cancer (NSCLC). In addition, there is evidence that the combination of bevacizumab and HIF-1 inhibitors increases antitumor activity. In this randomized phase II trial, chemo-naive patients with stage IV nonsquamous NSCLC were randomized to four cycles of carboplatin (area under the curve 6)-paclitaxel (200 mg/m(2))-bevacizumab 15 mg/kg on day 1 every 3 weeks with or without NTG patches 15 mg (day -2 to +2) followed by bevacizumab with or without NTG until progression. Response was assessed every two cycles. Primary end point was progression-free survival (PFS). The study was powered (80%) to detect a decrease in the hazard of tumor progression of 33% at α = 0.05 with a two-sided log-rank test when 222 patients were enrolled and followed until 195 events were observed. Between 1 January 2011 and 1 January 2013, a total of 223 patients were randomized; 112 control arm and 111 experimental arm; response rate was 54% in control arm and 38% in experimental arm. Median [95% confidence interval (CI)] PFS in control arm was 6.8 months (5.6-7.3) and 5.1 months (4.2-5.8) in experimental arm, hazard ratio (HR) 1.27 (95% CI 0.96-1.67). Overall survival (OS) was 11.6 months (8.8-13.6) in control arm and 9.4 months (7.8-11.3) in experimental arm, HR 1.02 (95% CI 0.71-1.46). In the experimental arm, no additional toxicity was observed except headache (6% versus 52% in patients treated with NTG). Adding NTG to first-line carboplatin-paclitaxel-bevacizumab did not improve PFS and OS in patients with stage IV nonsquamous NSCLC. © The Author 2015. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  7. A Cognitive Strategy Instruction to Improve Math Calculation for Children with ADHD and LD: A Randomized Controlled Study

    ERIC Educational Resources Information Center

    Iseman, Jackie S.; Naglieri, Jack A.

    2011-01-01

    The authors examined the effectiveness of cognitive strategy instruction based on PASS (Planning, Attention, Simultaneous, Successive) given by special education teachers to students with ADHD randomly assigned by classroom. Students in the experimental group were exposed to a brief cognitive strategy instruction for 10 days, which was designed to…

  8. Outcomes of an HIV Prevention Peer Group Intervention for Rural Adults in Malawi

    ERIC Educational Resources Information Center

    Kaponda, Chrissie P. N.; Norr, Kathleen F.; Crittenden, Kathleen S.; Norr, James L.; McCreary, Linda L.; Kachingwe, Sitingawawo I.; Mbeba, Mary M.; Jere, Diana L. N.; Dancy, Barbara L.

    2011-01-01

    This study used a quasi-experimental design to evaluate a six-session peer group intervention for HIV prevention among rural adults in Malawi. Two rural districts were randomly assigned to intervention and control conditions. Independent random samples of community adults compared the districts at baseline and at 6 and 18 months postintervention.…

  9. Fisher, Sir Ronald Aylmer (1890-1962)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Statistician, born in London, England. After studying astronomy using AIRY's manual on the Theory of Errors he became interested in statistics, and laid the foundation of randomization in experimental design, the analysis of variance and the use of data in estimating the properties of the parent population from which it was drawn. Invented the maximum likelihood method for estimating from random ...

  10. Summer Outreach with Near-Age Peer Mentors: A Randomized Experiment to Improve the Transition to College

    ERIC Educational Resources Information Center

    Schneider, Barbara; Broda, Michael; Judy, Justina

    2013-01-01

    Although students leave high school stating their plans to continue their education, some lack the information and strategies to successfully navigate a successful transition to college. This paper presents results from a randomized study that is part of a larger, quasi-experimental intervention, the College Ambition Program (CAP). The embedded…

  11. Realization of a Quantum Random Generator Certified with the Kochen-Specker Theorem

    NASA Astrophysics Data System (ADS)

    Kulikov, Anatoly; Jerger, Markus; Potočnik, Anton; Wallraff, Andreas; Fedorov, Arkady

    2017-12-01

    Random numbers are required for a variety of applications from secure communications to Monte Carlo simulation. Yet randomness is an asymptotic property, and no output string generated by a physical device can be strictly proven to be random. We report an experimental realization of a quantum random number generator (QRNG) with randomness certified by quantum contextuality and the Kochen-Specker theorem. The certification is not performed in a device-independent way but through a rigorous theoretical proof of each outcome being value indefinite even in the presence of experimental imperfections. The analysis of the generated data confirms the incomputable nature of our QRNG.

  12. Realization of a Quantum Random Generator Certified with the Kochen-Specker Theorem.

    PubMed

    Kulikov, Anatoly; Jerger, Markus; Potočnik, Anton; Wallraff, Andreas; Fedorov, Arkady

    2017-12-15

    Random numbers are required for a variety of applications from secure communications to Monte Carlo simulation. Yet randomness is an asymptotic property, and no output string generated by a physical device can be strictly proven to be random. We report an experimental realization of a quantum random number generator (QRNG) with randomness certified by quantum contextuality and the Kochen-Specker theorem. The certification is not performed in a device-independent way but through a rigorous theoretical proof of each outcome being value indefinite even in the presence of experimental imperfections. The analysis of the generated data confirms the incomputable nature of our QRNG.

  13. Effect of guava and vitamin C supplementation on experimental gingivitis A randomized clinical trial.

    PubMed

    Amaliya, Amaliya; Risdiana, Ajeng S; der Velden, Ubele Van

    2018-05-14

    To study the effect of guava and synthetic vitamin C on the development of gingival inflammation during experimental gingivitis. Participants were randomly assigned to three groups supplemented daily with either 200g guava, 200mg synthetic vitamin C or water. The study included a 14 days pre-experimental period with oral hygiene instructions, scaling, prophylaxis and supplementation. Thereafter, experiment gingivitis was initiated, while continuing supplementation. At baseline, day 7 and day 14 of experimental gingivitis, Plaque Index (PlI) and Gingival Index (GI) were assessed. During the entire study, dietary fruit/vegetables intake was minimal. PlI increased in guava-, vitamin C- and control group (ΔPlI: 1.30, 1.61 and 1.79 respectively). However, the guava group developed significantly less plaque compared to the control group. The GI increase of both guava- and vitamin C group was significantly less than the increase of the control group (ΔGI: 0.10, 0.24 and 0.87 respectively). in a population of young non-smoking adults, consumption of either 200g guava/day or 200mg synthetic vitamin C/day, prior to and during the oral hygiene abstention period, has a preventive effect on the development of experimental gingivitis as compared to the control group that developed the usual amount of experimental gingivitis. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  14. Effect of family presence on pain and anxiety during invasive nursing procedures in an emergency department: A randomized controlled experimental study.

    PubMed

    İşlekdemir, Burcu; Kaya, Nurten

    2016-01-01

    Patients generally prefer to have their family present during medical or nursing interventions. Family presence is assumed to reduce anxiety, especially during painful interventions. This study employed a randomized controlled experimental design to determine the effects of family presence on pain and anxiety during invasive nursing procedures. The study population consisted of patients hospitalized in the observation unit of the internal medicine section in the emergency department of a university hospital. The sample comprised 138 patients assigned into the experimental and control groups by drawing lots. The invasive nursing procedure was carried out in the presence of family members, for members of the experimental group, and without family members, for members of the control group. Thus, the effects of family presence on pain and anxiety during the administration of an invasive nursing procedure to patients were analyzed. The results showed that members of the experimental and control groups did not differ with respect to the pain and state anxiety scores during the intervention. Family presence does not influence the participants' pain and anxiety during an invasive nursing procedure. Thus, the decision regarding family presence during such procedures should be based on patient preference. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Cost-effectiveness of an experimental caries-control regimen in a 3.4-yr randomized clinical trial among 11-12-yr-old Finnish schoolchildren.

    PubMed

    Hietasalo, Pauliina; Seppä, Liisa; Lahti, Satu; Niinimaa, Ahti; Kallio, Jouko; Aronen, Pasi; Sintonen, Harri; Hausen, Hannu

    2009-12-01

    The aim of this study was to assess the cost-effectiveness of an experimental caries-control regimen in a randomized clinical trial (RCT) conducted in Pori, Finland, in 2001-2005. Children (n = 497) who were 11-12 yr of age and had at least one active initial caries lesion at baseline were studied. The children in the experimental group (n = 250) were offered an individually designed patient-centered regimen for caries control. The children in the control group (n = 247) received standard dental care. Furthermore, the whole population was exposed to continuous community-level oral health promotion. Individual costs of treatment procedures and outcomes (DMFS increment score) for the follow-up period of 3.4 yr were calculated for each child in both groups. The incremental cost-effectiveness ratio was euro 34.07 per averted DMF surface. The experimental regimen was more effective, and also more costly. However, the total costs decreased year after year, and for the last 2 yr the experimental regimen was less expensive than the standard dental care. The experimental regimen would probably have been more cost-effective than standard dental care if the follow-up period had been longer, the regimen less comprehensive, and/or if dental nurses had conducted the preventive procedures.

  16. The Effects of Reading from the Screen on the Reading Motivation Levels of Elementary 5th Graders

    ERIC Educational Resources Information Center

    Aydemir, Zeynep; Ozturk, Ergun

    2012-01-01

    This study aims to explore the effects of reading from the screen on elementary 5th grade students' reading motivation levels. It used the randomized control-group pretest-posttest model, which is a true experimental design. The study group consisted of 60 students, 30 experimental and 30 control, who were attending the 5th grade of a public…

  17. Do Early Literacy Skills in Children's First Language Promote Development of Skills in Their Second Language? An Experimental Evaluation of Transfer

    ERIC Educational Resources Information Center

    Goodrich, J. Marc; Lonigan, Christopher J.; Farver, JoAnn M.

    2013-01-01

    The purpose of this study was to evaluate the cross-language transfer of the emergent literacy skills of preschoolers who were Spanish-speaking language-minority children in the context of an experimental intervention study. Ninety-four children were randomly assigned either to a control condition (HighScope Preschool Curriculum) or to receive…

  18. Statistical process control in nursing research.

    PubMed

    Polit, Denise F; Chaboyer, Wendy

    2012-02-01

    In intervention studies in which randomization to groups is not possible, researchers typically use quasi-experimental designs. Time series designs are strong quasi-experimental designs but are seldom used, perhaps because of technical and analytic hurdles. Statistical process control (SPC) is an alternative analytic approach to testing hypotheses about intervention effects using data collected over time. SPC, like traditional statistical methods, is a tool for understanding variation and involves the construction of control charts that distinguish between normal, random fluctuations (common cause variation), and statistically significant special cause variation that can result from an innovation. The purpose of this article is to provide an overview of SPC and to illustrate its use in a study of a nursing practice improvement intervention. Copyright © 2011 Wiley Periodicals, Inc.

  19. In situ medical simulation investigation of emergency department procedural sedation with randomized trial of experimental bedside clinical process guidance intervention.

    PubMed

    Siegel, Nathan A; Kobayashi, Leo; Dunbar-Viveiros, Jennifer A; Devine, Jeffrey; Al-Rasheed, Rakan S; Gardiner, Fenwick G; Olsson, Krister; Lai, Stella; Jones, Mark S; Dannecker, Max; Overly, Frank L; Gosbee, John W; Portelli, David C; Jay, Gregory D

    2015-06-01

    Patient safety during emergency department procedural sedation (EDPS) can be difficult to study. Investigators sought to delineate and experimentally assess EDPS performance and safety practices of senior-level emergency medicine residents through in situ simulation. Study sessions used 2 pilot-tested EDPS scenarios with critical action checklists, institutional forms, embedded probes, and situational awareness questionnaires. An experimental informatics system was separately developed for bedside EDPS process guidance. Postgraduate year 3 and 4 subjects completed both scenarios in randomized order; only experimental subjects were provided with the experimental system during second scenarios. Twenty-four residents were recruited into a control group (n = 12; 6.2 ± 7.4 live EDPS experience) and experimental group (n = 12; 11.3 ± 8.2 live EDPS experience [P = 0.10]). Critical actions for EDPS medication selection, induction, and adverse event recognition with resuscitation were correctly performed by most subjects. Presedation evaluations, sedation rescue preparation, equipment checks, time-outs, and documentation were frequently missed. Time-outs and postsedation assessments increased during second scenarios in the experimental group. Emergency department procedural sedation safety probe detection did not change across scenarios in either group. Situational awareness scores were 51% ± 7% for control group and 58% ± 12% for experimental group. Subjects using the experimental system completed more time-outs and scored higher Simulation EDPS Safety Composite Scores, although without comprehensive improvements in EDPS practice or safety. Study simulations delineated EDPS and assessed safety behaviors in senior emergency medicine residents, who exhibited the requisite medical knowledge base and procedural skill set but lacked some nontechnical skills that pertain to emergency department microsystem functions and patient safety. The experimental system exhibited limited impact only on in-simulation time-out compliance.

  20. Quantum walk computation

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

    Kendon, Viv

    2014-12-04

    Quantum versions of random walks have diverse applications that are motivating experimental implementations as well as theoretical studies. Recent results showing quantum walks are “universal for quantum computation” relate to algorithms, to be run on quantum computers. We consider whether an experimental implementation of a quantum walk could provide useful computation before we have a universal quantum computer.

  1. Effective Secondary Science Programs: A Best-Evidence Synthesis

    ERIC Educational Resources Information Center

    Cheung, Alan; Slavin, Robert E.; Kim, Elizabeth; Lake, Cynthia

    2017-01-01

    This article reports a systematic review of research on science programs in grades 6-12. Twenty-one studies met inclusion criteria including use of randomized or quasi-experimental assignment to conditions, measures that assess content emphasized equally in experimental and control groups, and a duration of at least 12 weeks. Programs fell into…

  2. Students' Reactions to Manual-Based Treatments for Substance Abuse: An Exploratory Study

    ERIC Educational Resources Information Center

    Simons, Lori; Jacobucci, Raymond; Houston, Hank

    2006-01-01

    A quasi-experimental research design with quantitative and qualitative methodologies was conducted to explore reactions of 21 students to treatment manuals for substance abuse. Students were randomized to experimental (n = 11) and attention-control (n = 10) groups involving exposure to one of two manual-based therapy interventions. Quantitative…

  3. Leveraging Volunteers: An Experimental Evaluation of a Tutoring Program for Struggling Readers

    ERIC Educational Resources Information Center

    Jacob, Robin; Armstrong, Catherine; Bowden, A. Brooks; Pan, Yilin

    2016-01-01

    This study evaluates the impacts and costs of the Reading Partners program, which uses community volunteers to provide one-on-one tutoring to struggling readers in under-resourced elementary schools. The evaluation uses an experimental design. Students were randomly assigned within 19 different Reading Partners sites to a program or control…

  4. An Exploration of Students' Perceptions of Empirically Supported Treatments: The Significance of Gender and Ethnicity

    ERIC Educational Resources Information Center

    Simons, Lori; Giorgio, Tina; Houston, Hank; Jacobucci, Ray

    2007-01-01

    A secondary analysis of a quasi-experimental study was conducted to evaluate differences in students 'perceptions of empirically supported treatments (ESTS) randomized to experimental (n= 10) and attention-control (n= 10) manual-based therapy interventions. The results indicated that attitudinal changes took place for both groups. The results…

  5. Fostering Emotional Adjustment among Nigerian Adolescents with Rational Emotive Behaviour Therapy

    ERIC Educational Resources Information Center

    Adomeh, Ilu O. C.

    2006-01-01

    This study examined the efficacy of Albert Ellis' Rational Emotive Behaviour Therapy (REBT) in fostering emotional adjustment among Nigerian adolescents. Fifty senior secondary school students were randomly selected and divided equally into experimental and control groups. The experimental group was treated with REBT twice a week for six weeks.…

  6. Two-Way and Monolingual English Immersion in Preschool Education: An Experimental Comparison

    ERIC Educational Resources Information Center

    Barnett, W. Steven; Yarosz, Donald J.; Thomas, Jessica; Jung, Kwanghee; Blanco, Dulce

    2007-01-01

    An experimental study was conducted comparing the effects of dual language, or two-way immersion (TWI) and monolingual English immersion (EI) preschool education programs on children's learning. Three-and four-year old children were randomly assigned by lottery to either a newly established TWI Spanish/English program or a monolingual English…

  7. Attenders versus Slackers: A Classroom Demonstration of Quasi-Experimentation and Self-Selecting Samples

    ERIC Educational Resources Information Center

    Stellmack, Mark A.

    2013-01-01

    Studies of the effects of class attendance on class performance typically are quasi-experimental because students choose whether or not to attend class; that is, the samples are self-selecting. The lack of random assignment prevents one from establishing a causal relationship between attendance and performance. Relating attendance to performance…

  8. A randomized study of two methods of teaching perineal massage: effects on practice rates, episiotomy rates, and lacerations.

    PubMed

    Mynaugh, P A

    1991-09-01

    This study examined the effects of two methods of teaching perineal massage on the rates of practice of perineal massage, of episiotomy, and of lacerations in primiparas at birth. Couples in 20 randomly selected sections of four prenatal class series received routine printed and verbal instruction and a 12-minute video demonstration of perineal massage, or only the routine printed and verbal instruction. Women reported their practice rates in daily diary records, which were mailed to the researcher weekly. Hospital records provided delivery data. Of the 83 women, 23 (28%) practiced perineal massage: 16 (35.6%) in the experimental group, 7 (18.4%) controls. Even though the rate of practice almost doubled among experimental group women, the videotape instruction method was statistically nonsignificant. Episiotomy and laceration rates were not affected by teaching method. More severe lacerations occurred among the experimental group; however, the control group had almost four times as many severe (21%) as minor (5.3%) lacerations. The experimental group had twice as many severe (28.9%) as minor (13.3%) lacerations. These results were also nonsignificant.

  9. Using non-contact therapeutic touch to manage post-surgical pain in the elderly.

    PubMed

    McCormack, Guy L

    2009-01-01

    The purpose of this study was to investigate the effects of non-contact therapeutic touch on post-surgical pain in an elderly population receiving occupational therapy in an acute care hospital unit in the United States. Ninety participants were randomly assigned to three groups (experimental, control and placebo) using a three-group experimental pre-test-post-test design and a randomized clinical trial. The experimental group received the non-contact touch intervention, the control group received routine care and the placebo group received the sound of a metronome set at a steady slow pace. Objective measures included the Memorial Pain Scale, the Tellegen Absorption Scale, the Health Attribution Scale and measures of pulse rate and pupil size, which were performed as repeated measures. In the experimental group, 22 out of 30 (73%) demonstrated a statistically significant decrease in pain intensity scores from pre-test to post-test (t [7] = 7.24, p < 0.01) and were better able to participate in occupations. Further research is recommended to replicate this study. 2009 John Wiley & Sons, Ltd

  10. The Effects of the Bali Yoga Program for Breast Cancer Patients on Chemotherapy-Induced Nausea and Vomiting: Results of a Partially Randomized and Blinded Controlled Trial.

    PubMed

    Anestin, Annélie S; Dupuis, Gilles; Lanctôt, Dominique; Bali, Madan

    2017-10-01

    Complementary and alternative medicine has been shown to be beneficial in reducing chemotherapy-induced nausea and vomiting. However, conclusive results are lacking in order to confirm its usefulness. The purpose of this study was to determine whether a standardized yoga intervention could reduce these adverse symptoms. This was a partially randomized and blinded controlled trial comparing a standardized yoga intervention with standard care. Eligible patients were adults diagnosed with stages I to III breast cancer receiving chemotherapy. Patients randomized to the experimental group participated in an 8-week yoga program. There was no significant difference between the experimental and control groups on chemotherapy-induced nausea and vomiting after 8 weeks. Results suggest the yoga program is not beneficial in managing these adverse symptoms. However, considering preliminary evidence suggesting yoga's beneficial impact in cancer symptom management, methodological limitations should be explored and additional studies should be conducted.

  11. Quasi-experimental designs in practice-based research settings: design and implementation considerations.

    PubMed

    Handley, Margaret A; Schillinger, Dean; Shiboski, Stephen

    2011-01-01

    Although randomized controlled trials are often a gold standard for determining intervention effects, in the area of practice-based research (PBR), there are many situations in which individual randomization is not possible. Alternative approaches to evaluating interventions have received increased attention, particularly those that can retain elements of randomization such that they can be considered "controlled" trials. Methodological design elements and practical implementation considerations for two quasi-experimental design approaches that have considerable promise in PBR settings--the stepped-wedge design, and a variant of this design, a wait-list cross-over design, are presented along with a case study from a recent PBR intervention for patients with diabetes. PBR-relevant design features include: creation of a cohort over time that collects control data but allows all participants (clusters or patients) to receive the intervention; staggered introduction of clusters; multiple data collection points; and one-way cross-over into the intervention arm. Practical considerations include: randomization versus stratification, training run in phases; and extended time period for overall study completion. Several design features of practice based research studies can be adapted to local circumstances yet retain elements to improve methodological rigor. Studies that utilize these methods, such as the stepped-wedge design and the wait-list cross-over design, can increase the evidence base for controlled studies conducted within the complex environment of PBR.

  12. Results of a multisite randomized trial of supported employment interventions for individuals with severe mental illness.

    PubMed

    Cook, Judith A; Leff, H Stephen; Blyler, Crystal R; Gold, Paul B; Goldberg, Richard W; Mueser, Kim T; Toprac, Marcia G; McFarlane, William R; Shafer, Michael S; Blankertz, Laura E; Dudek, Ken; Razzano, Lisa A; Grey, Dennis D; Burke-Miller, Jane

    2005-05-01

    National probability surveys indicate that most individuals with schizophrenia and other severe mental illnesses are not employed. This multisite study tested the effectiveness of supported employment (SE) models combining clinical and vocational rehabilitation services to establish competitive employment. We randomly assigned 1273 outpatients with severe mental illness from 7 states in the United States to an experimental SE program or to a comparison or a services-as-usual condition, with follow-up for 24 months. Participants were interviewed semiannually, paid employment was tracked weekly, and vocational and clinical services were measured monthly. Mixed-effects random regression analysis was used to predict the likelihood of competitive employment, working 40 or more hours in a given month, and monthly earnings. Cumulative results during 24 months show that experimental group participants (359/648 [55%]) were more likely than those in the comparison programs (210/625 [34%]) to achieve competitive employment (chi(2) = 61.17; P<.001). Similarly, patients in experimental group programs (330/648 [51%]) were more likely than those in comparison programs (245/625 [39%]) to work 40 or more hours in a given month (chi(2) = 17.66; P<.001). Finally, participants in experimental group programs had significantly higher monthly earnings than those in the comparison programs (mean, US 122 dollars/mo [n=639] vs US 99 dollars/mo [n=622]); t(1259) = -2.04; P<.05). In the multivariate longitudinal analysis, experimental condition subjects were more likely than comparison group subjects to be competitively employed, work 40 or more hours in a given month, and have higher earnings, despite controlling for demographic, clinical, work history, disability beneficiary status, and study site confounders. Moreover, the advantage of experimental over comparison group participants increased during the 24-month study period. The SE models tailored by integrating clinical and vocational services were more effective than services as usual or unenhanced services.

  13. Animal-Assisted Therapies for Youth with or at risk for Mental Health Problems: A Systematic Review.

    PubMed

    Hoagwood, Kimberly Eaton; Acri, Mary; Morrissey, Meghan; Peth-Pierce, Robin

    2017-01-01

    To systematically review experimental evidence about animal-assisted therapies (AAT) for children or adolescents with or at risk for mental health conditions, we reviewed all experimental AAT studies published between 2000-2015, and compared studies by animal type, intervention, and outcomes. Studies were included if used therapeutically for children and adolescents (≤21 years) with or at risk for a mental health problem; used random assignment or a waitlist comparison/control group; and included child-specific outcome data. Of 1,535 studies, 24 met inclusion criteria. Of 24 studies identified, almost half were randomized controlled trials, with 9 of 11 published in the past two years. The largest group addresses equine therapies for autism. Findings are generally promising for positive effects associated with equine therapies for autism and canine therapies for childhood trauma. The AAT research base is slim; a more focused research agenda is outlined.

  14. Effect of aerobic exercise on peripheral nerve functions of population with diabetic peripheral neuropathy in type 2 diabetes: a single blind, parallel group randomized controlled trial.

    PubMed

    Dixit, Snehil; Maiya, Arun G; Shastry, B A

    2014-01-01

    To evaluate the effect of moderate intensity aerobic exercise (40%-60% of Heart Rate Reserve (HRR)) on diabetic peripheral neuropathy. A parallel-group, randomized controlled trial was carried out in a tertiary health care setting, India. The study comprised of experimental (moderate intensity aerobic exercise and standard care) and control groups (standard care). Population with type 2 diabetes with clinical neuropathy, defined as a minimum score of seven on the Michigan Diabetic Neuropathy Score (MDNS), was randomly assigned to experimental and control groups by computer generated random number tables. RANOVA was used for data analysis (p<0.05 was significant). A total of 87 patients with DPN were evaluated in the study. After randomization there were 47 patients in the control group and 40 patients in the experimental group. A comparison of two groups using RANOVA for anthropometric measures showed an insignificant change at eight weeks. For distal peroneal nerve's conduction velocity there was a significant difference in two groups at eight weeks (p<0.05), Degrees of freedom (Df)=1, 62, F=5.14, and p=0.03. Sural sensory nerve at eight weeks showed a significant difference in two groups for conduction velocity, Df =1, 60, F=10.16, and p=0.00. Significant differences in mean scores of MDNS were also observed in the two groups at eight weeks (p value significant<0.05). Moderate intensity aerobic exercises can play a valuable role to disrupt the normal progression of DPN in type 2 diabetes. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Tunable random lasing behavior in plasmonic nanostructures

    NASA Astrophysics Data System (ADS)

    Yadav, Ashish; Zhong, Liubiao; Sun, Jun; Jiang, Lin; Cheng, Gary J.; Chi, Lifeng

    2017-01-01

    Random lasing is desired in plasmonics nanostructures through surface plasmon amplification. In this study, tunable random lasing behavior was observed in dye molecules attached with Au nanorods (NRs), Au nanoparticles (NPs) and Au@Ag nanorods (NRs) respectively. Our experimental investigations showed that all nanostructures i.e., Au@AgNRs, AuNRs & AuNPs have intensive tunable spectral effects. The random lasing has been observed at excitation wavelength 532 nm and varying pump powers. The best random lasing properties were noticed in Au@AgNRs structure, which exhibits broad absorption spectrum, sufficiently overlapping with that of dye Rhodamine B (RhB). Au@AgNRs significantly enhance the tunable spectral behavior through localized electromagnetic field and scattering. The random lasing in Au@AgNRs provides an efficient coherent feedback for random lasers.

  16. Brownian motion properties of optoelectronic random bit generators based on laser chaos.

    PubMed

    Li, Pu; Yi, Xiaogang; Liu, Xianglian; Wang, Yuncai; Wang, Yongge

    2016-07-11

    The nondeterministic property of the optoelectronic random bit generator (RBG) based on laser chaos are experimentally analyzed from two aspects of the central limit theorem and law of iterated logarithm. The random bits are extracted from an optical feedback chaotic laser diode using a multi-bit extraction technique in the electrical domain. Our experimental results demonstrate that the generated random bits have no statistical distance from the Brownian motion, besides that they can pass the state-of-the-art industry-benchmark statistical test suite (NIST SP800-22). All of them give a mathematically provable evidence that the ultrafast random bit generator based on laser chaos can be used as a nondeterministic random bit source.

  17. Experimentally Generated Random Numbers Certified by the Impossibility of Superluminal Signaling

    NASA Astrophysics Data System (ADS)

    Bierhorst, Peter; Shalm, Lynden K.; Mink, Alan; Jordan, Stephen; Liu, Yi-Kai; Rommal, Andrea; Glancy, Scott; Christensen, Bradley; Nam, Sae Woo; Knill, Emanuel

    Random numbers are an important resource for applications such as numerical simulation and secure communication. However, it is difficult to certify whether a physical random number generator is truly unpredictable. Here, we exploit the phenomenon of quantum nonlocality in a loophole-free photonic Bell test experiment to obtain data containing randomness that cannot be predicted by any theory that does not also allow the sending of signals faster than the speed of light. To certify and quantify the randomness, we develop a new protocol that performs well in an experimental regime characterized by low violation of Bell inequalities. Applying an extractor function to our data, we obtain 256 new random bits, uniform to within 10- 3 .

  18. Does the patient-held record improve continuity and related outcomes in cancer care: a systematic review.

    PubMed

    Gysels, Marjolein; Richardson, Alison; Higginson, Irene J

    2007-03-01

    To assess the effectiveness of the patient-held record (PHR) in cancer care. Patients with cancer may receive care from different services resulting in gaps. A PHR could provide continuity and patient involvement in care. Relevant literature was identified through five electronic databases (Medline, Embase, Cinahl, CCTR and CDSR) and hand searches. Patient-held records in cancer care with the purpose of improving communication and information exchange between and within different levels of care and to promote continuity of care and patients' involvement in their own care. Data extraction recorded characteristics of intervention, type of study and factors that contributed to methodological quality of individual studies. Data were then contrasted by setting, objectives, population, study design, outcome measures and changes in outcome, including knowledge, satisfaction, anxiety and depression. Methodological quality of randomized control trials and non-experimental studies were assessed with separate standard grading scales. Seven randomized control trials and six non-experimental studies were identified. Evaluations of the PHR have reached equivocal findings. Randomized trials found an absence of effect, non-experimental evaluations shed light on the conditions for its successful use. Most patients welcomed introduction of a PHR. Main problems related to its suitability for different patient groups and the lack of agreement between patients and health professionals regarding its function. Further research is required to determine the conditions under which the PHR can realize its potential as a tool to promote continuity of care and patient participation.

  19. Mirror Therapy with Neuromuscular Electrical Stimulation for improving motor function of stroke survivors: A pilot randomized clinical study.

    PubMed

    Lee, DongGeon; Lee, GyuChang; Jeong, JiSim

    2016-07-27

    This study was to investigate the effects of Mirror Therapy (MT) combined with Neuromuscular Electrical Stimulation (NMES) on muscle strength and tone, motor function, balance, and gait ability in stroke survivors with hemiplegia. This study was a randomized controlled trial. Twenty-seven hemiplegic stroke survivors from a rehabilitation center participated in the study. The participants were randomly assigned to either an experimental or a control group. The experimental group (n = 14) underwent MT combined with NMES and conventional physical therapy, and the control group (n = 13) underwent conventional physical therapy alone. Muscle strength and tone, balance, and gait ability were examined at baseline and after 4 weeks of intervention. A hand-held dynamometer was used to assess muscle strength, the Modified Ashworth Scale (MAS) was used to assess muscle tone, the Berg Balance Scale (BBS) and Timed Up and Go test (TUG) were used to ascertain balance, and the 6-m Walk Test (6mWT) was used to examine gait ability. After the intervention, compared to baseline values, there were significant improvements in muscle strength and MAS, BBS, TUG, and 6mWT values in the experimental group (P< 0.05). In addition, at post-intervention, there were significant differences between the two groups in muscle strength and BBS (P< 0.05). MT combined with NMES may effectively improve muscle strength and balance in hemiplegic stroke survivors. However, further studies are necessary to demonstrate brain reorganization after MT combined with NMES.

  20. A Simulation Study on the Performance of the Simple Difference and Covariance-Adjusted Scores in Randomized Experimental Designs.

    PubMed

    Petscher, Yaacov; Schatschneider, Christopher

    2011-01-01

    Research by Huck and McLean (1975) demonstrated that the covariance-adjusted score is more powerful than the simple difference score, yet recent reviews indicate researchers are equally likely to use either score type in two-wave randomized experimental designs. A Monte Carlo simulation was conducted to examine the conditions under which the simple difference and covariance-adjusted scores were more or less powerful to detect treatment effects when relaxing certain assumptions made by Huck and McLean (1975). Four factors were manipulated in the design including sample size, normality of the pretest and posttest distributions, the correlation between pretest and posttest, and posttest variance. A 5 × 5 × 4 × 3 mostly crossed design was run with 1,000 replications per condition, resulting in 226,000 unique samples. The gain score was nearly as powerful as the covariance-adjusted score when pretest and posttest variances were equal, and as powerful in fan-spread growth conditions; thus, under certain circumstances the gain score could be used in two-wave randomized experimental designs.

  1. A Simulation Study on the Performance of the Simple Difference and Covariance-Adjusted Scores in Randomized Experimental Designs

    PubMed Central

    Petscher, Yaacov; Schatschneider, Christopher

    2015-01-01

    Research by Huck and McLean (1975) demonstrated that the covariance-adjusted score is more powerful than the simple difference score, yet recent reviews indicate researchers are equally likely to use either score type in two-wave randomized experimental designs. A Monte Carlo simulation was conducted to examine the conditions under which the simple difference and covariance-adjusted scores were more or less powerful to detect treatment effects when relaxing certain assumptions made by Huck and McLean (1975). Four factors were manipulated in the design including sample size, normality of the pretest and posttest distributions, the correlation between pretest and posttest, and posttest variance. A 5 × 5 × 4 × 3 mostly crossed design was run with 1,000 replications per condition, resulting in 226,000 unique samples. The gain score was nearly as powerful as the covariance-adjusted score when pretest and posttest variances were equal, and as powerful in fan-spread growth conditions; thus, under certain circumstances the gain score could be used in two-wave randomized experimental designs. PMID:26379310

  2. Alleviating Parenting Stress in Parents with Intellectual Disabilities: A Randomized Controlled Trial of a Video-feedback Intervention to Promote Positive Parenting.

    PubMed

    Hodes, Marja W; Meppelder, Marieke; de Moor, Marleen; Kef, Sabina; Schuengel, Carlo

    2017-05-01

    Adapted parenting support may alleviate the high levels of parenting stress experienced by many parents with intellectual disabilities. Parents with mild intellectual disabilities or borderline intellectual functioning were randomized to experimental (n = 43) and control (n = 42) conditions. Parents in both groups received care-as-usual. The experimental group also received an adapted version of video-feedback intervention for positive parenting and learning difficulties (VIPP-LD). Measures of parenting stress were obtained pre-test, post-test and 3-month follow-up. Randomization to the experimental group led to a steeper decline in parenting stress related to the child compared to the control group (d = 0.46). No statistically significant effect on stress related to the parent's own functioning or situation was found. The results of the study suggest the feasibility of reducing parenting stress in parents with mild intellectual disability (MID) through parenting support, to the possible benefit of their children. © 2016 John Wiley & Sons Ltd.

  3. Evaluation of a smartphone application for self-care performance of patients with chronic hepatitis B: A randomized controlled trial.

    PubMed

    Jeon, Jae Hee

    2016-11-01

    To verify the usefulness of a smartphone application (App) for facilitating self-care in patients with chronic hepatitis B (CHB). CHB is a global health problem, and patients with CHB need to routinely perform self-care. Health-related smartphone apps could help users self-manage their disease. Fifty-three CHB patients were assessed in this randomized controlled before-and-after experimental study. The patients were randomly and equally assigned to groups that did (n=26) or did not (n=27) use the smartphone app for 12weeks. The experimental and control groups were analyzed for differences in disease knowledge, self-efficacy, and self-care before and after use of the smartphone app. After intervention, patients who used the app displayed significantly increased disease knowledge compared with the control group (p=.015). Self-efficacy and self-care also significantly increased in the experimental group (p=0.006 and 0.001, respectively). The smartphone app can be useful for increasing self-care in CHB patients. App: application, CHB: chronic hepatitis B, CVI: content validity. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Improvement of spontaneous language in stroke patients with chronic aphasia treated with music therapy: a randomized controlled trial.

    PubMed

    Raglio, Alfredo; Oasi, Osmano; Gianotti, Marta; Rossi, Agnese; Goulene, Karine; Stramba-Badiale, Marco

    2016-01-01

    The aim of this research is to evaluate the effects of active music therapy (MT) based on free-improvisation (relational approach) in addition to speech language therapy (SLT) compared with SLT alone (communicative-pragmatic approach: Promoting Aphasic's Communicative Effectiveness) in stroke patients with chronic aphasia. The experimental group (n = 10) was randomized to 30 MT individual sessions over 15 weeks in addition to 30 SLT individual sessions while the control group (n = 10) was randomized to only 30 SLT sessions during the same period. Psychological and speech language assessment were made before (T0) and after (T1) the treatments. The study shows a significant improvement in spontaneous speech in the experimental group (Aachener Aphasie subtest: p = 0.020; Cohen's d = 0.35); the 50% of the experimental group showed also an improvement in vitality scores of Short Form Health Survey (chi-square test = 4.114; p = 0.043). The current trial highlights the possibility that the combined use of MT and SLT can lead to a better result in the rehabilitation of patients with aphasia than SLT alone.

  5. Extensions of Existing Methods for Use with a New Class of Experimental Designs Useful when There Is Treatment Effect Contamination

    ERIC Educational Resources Information Center

    Rhoads, Christopher

    2011-01-01

    Researchers planning a randomized field trial to evaluate the effectiveness of an educational intervention often face the following dilemma. They plan to recruit schools to participate in their study. The question is, "Should the researchers randomly assign individuals (either students or teachers, depending on the intervention) within schools to…

  6. Promoting the Purchase of Low-Calorie Foods from School Vending Machines: A Cluster-Randomized Controlled Study

    ERIC Educational Resources Information Center

    Kocken, Paul L.; Eeuwijk, Jennifer; van Kesteren, Nicole M.C.; Dusseldorp, Elise; Buijs, Goof; Bassa-Dafesh, Zeina; Snel, Jeltje

    2012-01-01

    Background: Vending machines account for food sales and revenue in schools. We examined 3 strategies for promoting the sale of lower-calorie food products from vending machines in high schools in the Netherlands. Methods: A school-based randomized controlled trial was conducted in 13 experimental schools and 15 control schools. Three strategies…

  7. Resistivity and magnetoresistivity of amorphous rare-earth alloys

    NASA Astrophysics Data System (ADS)

    Borchi, E.; Poli, M.; De Gennaro, S.

    1982-05-01

    The resistivity and magnetoresistivity of amorphous rare-earth alloys are studied starting from the general approach of Van Peski-Tinbergen and Dekker. The random axial crystal-field and the magnetic correlations between the rare-earth ions are consistently taken into account. The characteristic features of the available experimental data are explained both of the case of random ferromagnetic and antiferromagnetic order.

  8. Combining Randomized and Non-Randomized Evidence in Clinical Research: A Review of Methods and Applications

    ERIC Educational Resources Information Center

    Verde, Pablo E.; Ohmann, Christian

    2015-01-01

    Researchers may have multiple motivations for combining disparate pieces of evidence in a meta-analysis, such as generalizing experimental results or increasing the power to detect an effect that a single study is not able to detect. However, while in meta-analysis, the main question may be simple, the structure of evidence available to answer it…

  9. The effects of preoperative aromatherapy massage on anxiety and sleep quality of colorectal surgery patients: A randomized controlled study.

    PubMed

    Ayik, Cahide; Özden, Dilek

    2018-02-01

    To examine the effects of aromatherapy massage on anxiety and sleep quality in patients undergoing colorectal surgery in the preoperative period. In recent years, there has been an increase in the number of studies conducted on aromatherapy massage. It is stated that studies conducted on aromatherapy massage for anxiety and sleep quality reveal contradictory results and that more research is required on the issue. A randomized controlled trial. Eighty patients undergoing colorectal surgery were randomly assigned to experimental and control group. To the experimental group (n = 40), aromatherapy massage was applied in accordance with the "Back Massage Guide" using 5% lavender oil (Lavandula Hybrida) for ten minutes before surgery and the morning of surgery. The control group received standard nursing care in compliance with the hospital procedure. Data were obtained by the State Anxiety Inventory (SAI) and Richard-Campbell Sleep Questionnaire (RCSQ). Results were analyzed using the t-test, Chi-square test or Fisher's exact test. There was no baseline difference between the groups. A statistically significant difference was found between the experimental and control group in terms of the SAI and RCSQ mean scores recorded on the morning of surgery. It was determined that the SAI and RCSQ mean score of the experimental group after aromatherapy massage on the morning of surgery decreased when compared to that of the evening before surgery. It was found that aromatherapy massage with lavender oil increased the sleep quality and reduced the level of anxiety in patients with colorectal surgery in the preoperative period. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Effects of pleasant olfactory mental imagery on the arterial oxygenation in patients with open heart surgery: A randomized controlled trial.

    PubMed

    Rezaei-Nodehi, Masoud; Bagheri-Nesami, Masoumeh; Shorofi, Seyed Afshin; Yazdani-Charati, Jamshid; Ghafari, Rahman

    2017-11-01

    Arterial hypoxemia is one of the most common respiratory complications following cardiac surgery. This study was intended to examine the effects of pleasant olfactory mental imagery on postoperative hypoxemia in patients undergoing open heart surgery. This is a randomized controlled clinical trial. The sample consisted of 80 patients who were randomly assigned to either practice olfactory mental imagery (experimental group) or receive routine care (control group). A card with the image of roses was given to patients and they were asked to look at the image, visualize the scent of roses in the mind, and then sniff as much as possible, hold their breath for 2 s and eventually exhale slowly through the nose. This procedure was consecutively repeated five times. After a fifteen-minute break, patients proceeded to practice olfactory mental imagery with other fruit images. The experimental group executed the olfactory mental imagery for two hours in the morning and two hours in the afternoon on postoperative days 1 and 2. No statistically significant differences were observed between the experimental and control groups regarding sociodemographic characteristics, medical and surgical information. This study also demonstrated that the mean Spao2 was significantly higher in the experimental group (97.400 ± 1.70) than the control group (96.465 ± 1.70) (p = 0.015). The results of this study suggest that olfactory mental imagery can improve arterial oxygenation in patients with cardiac surgery. Copyright © 2017. Published by Elsevier Ltd.

  11. A randomized control study of psychological intervention to reduce anxiety, amotivation and psychological distress among medical students.

    PubMed

    Saravanan, Coumaravelou; Kingston, Rajiah

    2014-05-01

    Test anxiety aggravates psychological distress and reduces the motivation among graduate students. This study aimed to identify psychological intervention for test anxiety, which reduces the level of psychological distress, amotivation and increases the intrinsic and extrinsic motivation among medical students. Westside test anxiety scale, Kessler Perceived Stress Scale and Academic Motivation Scale were used to measure test anxiety, psychological distress and motivation on 436 1(st) year medical students. Out of 436 students, 74 students who exhibited moderate to high test anxiety were randomly divided into either experimental or waiting list group. In this true randomized experimental study, 32 participants from the intervention group received five sessions of psychological intervention consist of psychoeducation, relaxation therapy and systematic desensitization. Thirty-three students from waiting list received one session of advice and suggestions. After received psychological intervention participants from the intervention group experienced less anxiety, psychological distress, and amotivation (P < 0.01) and high intrinsic and extrinsic motivation (P < 0.01) in the postassessment compared with their preassessment scores. Overall psychological intervention is effective to reduce anxiety scores and its related variables.

  12. A Cross-Sectional Analysis of Publication Types in Quality Improvement Journals.

    PubMed

    Wong, Christopher J; White, Andrew A; Merel, Susan E; Brock, Douglas M; Staiger, Thomas O

    2016-07-01

    Despite widespread engagement in quality improvement activities, little is known about the designs of studies currently published in quality improvement journals. This study's goal is to establish the prevalence of the types of research conducted in articles published in journals dedicated to quality improvement. A cross-sectional analysis was performed of 145 research articles published in 11 quality improvement journals in 2011. The majority of study designs were considered pre-experimental (95%), with a small percentage of quasi-experimental and experimental designs. Of the studies that reported the results of an intervention (n = 60), the most common research designs were pre-post studies (33%) and case studies (25%). There were few randomized controlled trials or quasi-experimental study designs (12% of intervention studies). These results suggest that there are opportunities for increased use of quasi-experimental study designs. © The Author(s) 2015.

  13. The Effect of Acupressure at Spleen 6 Acupuncture Point on the Anxiety Level and Sedative and Analgesics Consumption of Women during Labor: A Randomized, Single-blind Clinical Trial

    PubMed Central

    Samadi, Parisa; Alipour, Zahra; Lamyian, Minoor

    2018-01-01

    Background: Labor pain is the most severe pain women would experience, which could lead to loss of emotional control that plays a key role in creating a traumatic delivery experience and psychological disorders. The goal of this study was to evaluate the effect of acupressure on anxiety level and sedative and analgesics consumption in women during labor. Materials and Methods: This study was a randomized, single-blind clinical trial performed at Maryam Hospital in Tehran, Iran. One hundred and thirty-one pregnant women in Labor Ward were selected by convenience sampling. Subjects were randomly allocated to three groups, namely experimental group (pressure group), control group 1(touh group) and, control group 2 (routine care group). The study data were gathered using demographic information form, and assessed with Faces Anxiety Scale (FAS). For participants belonging to the experimental group, pressure was applied to the Spleen 6 acupoint for 30 min, and for those with only light touch was applied to the Spleen 6 acupoint for 30 min. The collected data were analyzed using Statistical Package for the Social Sciences 16 and descriptive statistics. Results: There was a significant difference between the three groups in terms of the mean of anxiety after 30 min of starting the intervention and 30 min after termination of the intervention; the anxiety of the experimental group was significantly decreased (p = 0.03). Sedative and analgesics consumption was significantly lower in the experimental group compared to the other groups (p = 0.006). Conclusions: This study showed that compression of the Spleen 6 acupoint was an effective complementary method to decrease maternal anxiety and analgesic consumption, especially pethidine. PMID:29628954

  14. Evaluation of a Two-Phase Experimental Study of a Small Group ("MultiLit") Reading Intervention for Older Low-Progress Readers

    ERIC Educational Resources Information Center

    Buckingham, Jennifer; Beaman-Wheldall, Robyn; Wheldall, Kevin

    2014-01-01

    The study reported here examined the efficacy of a small group (Tier 2 in a three-tier Response to Intervention model) literacy intervention for older low-progress readers (in Years 3-6). This article focuses on the second phase of a two-phase, crossover randomized control trial involving 26 students. In Phase 1, the experimental group (E1)…

  15. Efficacy of eye movement desensitization and reprocessing on the phantom limb pain of patients with amputations within a 24-month follow-up.

    PubMed

    Rostaminejad, Akbar; Behnammoghadam, Mohammad; Rostaminejad, Marzieh; Behnammoghadam, Zargham; Bashti, Somaye

    2017-09-01

    The aim of this study was to evaluate the efficacy of eye movement desensitization and reprocessing (EMDR) on the phantom limb pain (PLP) of patients with amputations within a 24-month follow-up. This study was a randomized-controlled trial. A total of 60 patients with amputations were selected by a purposive sampling and patients were divided randomly into two experimental and control groups. Samples were assigned through randomized allocation. EMDR therapy was administered individually to the experimental group participants in 12 one-hour sessions over a 1-month period In each session, the patient completed the Subjective Units of Distress Scale and a pain-rating scale before and after the intervention. Follow-up measures were obtained 24 months later for the experimental group. The participants in the control group were measured on the two scales at an initial session and again after 1- and 24-month follow-up. The mean PLP decreased in the experimental group between the first and last sessions and remained so at a 24-month follow-up. No decrease occurred for the control group over the 1- and 24-month period. The differences were statistically significant (P<0.001) according to a repeated-measures analysis of variance. EMDR therapy proved to be a successful treatment for PLP. Because of its efficacy and the fact that the positive effects were maintained at the 24-month follow-up, this therapy is recommended for the treatment of PLP.

  16. Effect of perioperative parecoxib sodium on postoperative pain control for transcatheter arterial chemoembolization for inoperable hepatocellular carcinoma: a prospective randomized trial.

    PubMed

    Lv, Ning; Kong, Yanan; Mu, Luwen; Pan, Tao; Xie, Qiankun; Zhao, Ming

    2016-10-01

    Pain is one of the most common side effects of transcatheter arterial chemoembolization (TACE) treatment. This study aimed to assess the analgesic effect of parecoxib sodium for postoperative pain control in patients with inoperable hepatocellular carcinoma (HCC) undergoing TACE. This randomized placebo-controlled prospective clinical study was conducted at a single cancer centre. Patients were randomly assigned to receive parecoxib sodium (experimental group; n = 60) or 0.9 % sodium chloride (control group; n = 60) 1 h before TACE and once every 12 h for 2 days after TACE. Pain level, morphine consumption, adverse events, and quality of life were evaluated and compared between the two groups. Pain scores, percentage distribution of pain categories, and morphine consumption were significantly lower in the experimental group than in the control group (P < 0.05). Fever score comparisons revealed significantly better body temperature balance in the experimental group than in the control group (P = 0.024). Quality-of-life scores in the experimental group were significantly better than those in the control group (P < 0.05). Our results demonstrate that the perioperative administration of parecoxib significantly improved its effectiveness in the control of postoperative pain after TACE. • Perioperative administration of parecoxib is effective for control of pain after TACE. • COX-2 inhibitors provide effective and safe pain control. • Parecoxib helps improve quality-of-life after TACE for patients with inoperable hepatocellular carcinoma.

  17. Long-lasting effects of a new memory self-efficacy training for stroke patients: a randomized controlled trial.

    PubMed

    Aben, Laurien; Heijenbrok-Kal, Majanka H; Ponds, Rudolf W H M; Busschbach, Jan J V; Ribbers, Gerard M

    2014-01-01

    This study aims to determine the long-term effects of a new Memory Self-efficacy (MSE) training program for stroke patients on MSE, depression, and quality of life. In a randomized controlled trial, patients were allocated to a MSE training or a peer support group. Outcome measures were MSE, depression, and quality of life, measured with the Metamemory-In-Adulthood questionnaire, Center for Epidemiological Studies-Depression Scale (CES-D), and the Who-Qol Bref questionnaire, respectively. We used linear mixed models to compare the outcomes of both groups immediately after training, after 6 months, and after 12 months, adjusted for baseline. In total, 153 former inpatients from 2 rehabilitation centers were randomized-77 to the experimental and 76 to the control group. MSE increased significantly more in the experimental group and remained significantly higher than in the control group after 6 and 12 months (B = 0.42; P = .010). Psychological quality of life also increased more in the experimental group but not significantly (B = 0.09; P = .077). However, in the younger subgroup of patients (<65 years old), psychological quality of life significantly improved in the experimental group compared to the control group and remained significantly higher over time (B = 0.14; P = .030). Other outcome measures were not significantly different between both groups. An MSE training program improved MSE and psychological quality of life in stroke patients aged <65 years. These effects persisted during 12 months of follow-up.

  18. Study of The Vector Product using Three Dimensions Vector Card of Engineering in Pathumwan Institute of Technology

    NASA Astrophysics Data System (ADS)

    Mueanploy, Wannapa

    2015-06-01

    The objective of this research was to offer the way to improve engineering students in Physics topic of vector product. The sampling of this research was the engineering students at Pathumwan Institute of Technology during the first semester of academic year 2013. 1) Select 120 students by random sampling are asked to fill in a satisfaction questionnaire scale, to select size of three dimensions vector card in order to apply in the classroom. 2) Select 60 students by random sampling to do achievement test and take the test to be used in the classroom. The methods used in analysis of achievement test by the Kuder-Richardson Method (KR- 20). The results show that 12 items of achievement test are appropriate to be applied in the classroom. The achievement test gets Difficulty (P) = 0.40-0.67, Discrimination = 0.33-0.73 and Reliability (r) = 0.70.The experimental in the classroom. 3) Select 60 students by random sampling divide into two groups; group one (the controlled group) with 30 students was chosen to study in the vector product lesson by the regular teaching method. Group two (the experimental group) with 30 students was chosen to learn the vector product lesson with three dimensions vector card. 4) Analyzed data between the controlled group and the experimental group, the result showed that experimental group got higher achievement test than the controlled group significant at .01 level.

  19. Quasi-experimental evaluation without regression analysis.

    PubMed

    Rohrer, James E

    2009-01-01

    Evaluators of public health programs in field settings cannot always randomize subjects into experimental or control groups. By default, they may choose to employ the weakest study design available: the pretest, posttest approach without a comparison group. This essay argues that natural experiments involving comparison groups are within reach of public health program managers. Methods for analyzing natural experiments are discussed.

  20. Effects of Computer-Assisted Instruction on Performance of Senior High School Biology Students in Ghana

    ERIC Educational Resources Information Center

    Owusu, K. A.; Monney, K. A.; Appiah, J. Y.; Wilmot, E. M.

    2010-01-01

    This study investigated the comparative efficiency of computer-assisted instruction (CAI) and conventional teaching method in biology on senior high school students. A science class was selected in each of two randomly selected schools. The pretest-posttest non equivalent quasi experimental design was used. The students in the experimental group…

  1. The Effect of a Sport Stacking Intervention on Handwriting with Second Grade Students

    ERIC Educational Resources Information Center

    Li, Yuhua; Coleman, Diane; Ransdell, Mary; Coleman, Lyndsie; Irwin, Carol

    2014-01-01

    The present study examined the impact a 14-week sport stacking (cup stacking) exercise intervention would have on children's handwriting quality and speed. Eighty-three second graders were randomly assigned to either an experimental or a control group. The experimental group (n = 42) participated in a 15-min session of sport stacking activities…

  2. An Experimental Investigation into the Efficiency of Cooperative Learning with Consideration of Multiple Grouping Criteria

    ERIC Educational Resources Information Center

    Hsiung, C. -M.

    2010-01-01

    The present study conducts an experimental investigation to compare the efficiency of the cooperative learning method with that of the traditional learning method. A total of 42 engineering students are randomly assigned to the two learning conditions and are formed into mixed-ability groups comprising three team members. In addition to the…

  3. Argumentation Practices in Classroom: Pre-Service Teachers' Conceptual Understanding of Chemical Equilibrium

    ERIC Educational Resources Information Center

    Kaya, Ebru

    2013-01-01

    This study examines the impact of argumentation practices on pre-service teachers' understanding of chemical equilibrium. The sample consisted of 100 pre-service teachers in two classes of a public university. One of these classes was assigned as experimental and the other as control group, randomly. In the experimental group, the subject of…

  4. Aggregate and Individual Replication Probability within an Explicit Model of the Research Process

    ERIC Educational Resources Information Center

    Miller, Jeff; Schwarz, Wolf

    2011-01-01

    We study a model of the research process in which the true effect size, the replication jitter due to changes in experimental procedure, and the statistical error of effect size measurement are all normally distributed random variables. Within this model, we analyze the probability of successfully replicating an initial experimental result by…

  5. The Effects of Accelerated Math Utilization on Grade Equivalency Score at a Selected Elementary School

    ERIC Educational Resources Information Center

    Kariuki, Patrick; Gentry, Christi

    2010-01-01

    The purpose of this study was to examine the effects of Accelerated Math utilization on students' grade equivalency scores. Twelve students for both experimental and control groups were randomly selected from 37 students enrolled in math in grades four through six. The experimental group consisted of the students who actively participated in…

  6. An Experimental Evaluation of the Effectiveness of an Audio-Tutorial Method in Teaching Vocational Agriculture.

    ERIC Educational Resources Information Center

    McVey, Gary C.

    To determine the effectiveness of an audio-tutorial technique in vocational agriculture, six treatment schools and six control schools were randomly selected from 48 Iowa high schools qualifying for participation in the study. While each school was provided the same reference material and teaching outline for the 14-day experimental period, the…

  7. Does Comparing Solution Methods Facilitate Conceptual and Procedural Knowledge? An Experimental Study on Learning to Solve Equations

    ERIC Educational Resources Information Center

    Rittle-Johnson, Bethany; Star, Jon R.

    2007-01-01

    Encouraging students to share and compare solution methods is a key component of reform efforts in mathematics, and comparison is emerging as a fundamental learning mechanism. To experimentally evaluate the effects of comparison for mathematics learning, the authors randomly assigned 70 seventh-grade students to learn about algebra equation…

  8. Practising Mental Rotation Using Interactive Desktop Mental Rotation Trainer (iDeMRT)

    ERIC Educational Resources Information Center

    Rafi, Ahmad; Samsudin, Khairulanuar

    2009-01-01

    An experimental study involving 30 undergraduates (mean age = 20.5 years) in mental rotation (MR) training was conducted in an interactive Desktop Mental Rotation Trainer (iDeMRT). Stratified random sampling assigned students into one experimental group and one control group. The former trained in iDeMRT and the latter trained in conventional…

  9. The Computer as a Teaching Aid for Eleventh Grade Mathematics: A Comparison Study.

    ERIC Educational Resources Information Center

    Kieren, Thomas Ervin

    To determine the effect of learning computer programming and the use of a computer on mathematical achievement of eleventh grade students, for each of two years, average and above average students were randomly assigned to an experimental and control group. The experimental group wrote computer programs and used the output from the computer in…

  10. A Randomized Experimental Study of Gender-Responsive Substance Abuse Treatment for Women in Prison

    PubMed Central

    Messina, Nena; Grella, Christine E.; Cartier, Jerry; Torres, Stephanie

    2009-01-01

    This experimental pilot study compared post-release outcomes for 115 women who participated in prison-based substance abuse treatment. Women were randomized to a gender-responsive treatment (GRT) program using manualized curricula (Helping Women Recover and Beyond Trauma) or a standard prison-based therapeutic community (TC). Data were collected from the participants at prison program entry and 6 and 12 months after release. Bivariate and multivariate analyses were conducted. Results indicate that both groups improved in psychological well-being; however, GRT participants had greater reductions in drug use, were more likely to remain in residential aftercare longer (2.6 months vs. 1.8 months, p < .05), and were less likely to have been reincarcerated within 12 months after parole (31% vs. 45%, respectively; a 67% reduction in odds for the experimental group, p < .05). Findings show the beneficial effects of treatment components oriented toward women's needs and support the integration of GRT in prison programs for women. PMID:20015605

  11. Quasi experimental designs in pharmacist intervention research.

    PubMed

    Krass, Ines

    2016-06-01

    Background In the field of pharmacist intervention research it is often difficult to conform to the rigorous requirements of the "true experimental" models, especially the requirement of randomization. When randomization is not feasible, a practice based researcher can choose from a range of "quasi-experimental designs" i.e., non-randomised and at time non controlled. Objective The aim of this article was to provide an overview of quasi-experimental designs, discuss their strengths and weaknesses and to investigate their application in pharmacist intervention research over the previous decade. Results In the literature quasi experimental studies may be classified into five broad categories: quasi-experimental design without control groups; quasi-experimental design that use control groups with no pre-test; quasi-experimental design that use control groups and pre-tests; interrupted time series and stepped wedge designs. Quasi-experimental study design has consistently featured in the evolution of pharmacist intervention research. The most commonly applied of all quasi experimental designs in the practice based research literature are the one group pre-post-test design and the non-equivalent control group design i.e., (untreated control group with dependent pre-tests and post-tests) and have been used to test the impact of pharmacist interventions in general medications management as well as in specific disease states. Conclusion Quasi experimental studies have a role to play as proof of concept, in the pilot phases of interventions when testing different intervention components, especially in complex interventions. They serve to develop an understanding of possible intervention effects: while in isolation they yield weak evidence of clinical efficacy, taken collectively, they help build a body of evidence in support of the value of pharmacist interventions across different practice settings and countries. However, when a traditional RCT is not feasible for logistical and/or ethical reasons researchers should endeavour to use the more robust of the quasi experimental designs.

  12. Random electric field instabilities of relaxor ferroelectrics

    NASA Astrophysics Data System (ADS)

    Arce-Gamboa, José R.; Guzmán-Verri, Gian G.

    2017-06-01

    Relaxor ferroelectrics are complex oxide materials which are rather unique to study the effects of compositional disorder on phase transitions. Here, we study the effects of quenched cubic random electric fields on the lattice instabilities that lead to a ferroelectric transition and show that, within a microscopic model and a statistical mechanical solution, even weak compositional disorder can prohibit the development of long-range order and that a random field state with anisotropic and power-law correlations of polarization emerges from the combined effect of their characteristic dipole forces and their inherent charge disorder. We compare and reproduce several key experimental observations in the well-studied relaxor PbMg1/3Nb2/3O3-PbTiO3.

  13. Use of a Linear Paul Trap to Study Random Noise-Induced Beam Degradation in High-Intensity Accelerators

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

    Chung, Moses; Gilson, Erik P.; Davidson, Ronald C.

    2009-04-10

    A random noise-induced beam degradation that can affect intense beam transport over long propagation distances has been experimentally studied by making use of the transverse beam dynamics equivalence between an alternating-gradient (AG) focusing system and a linear Paul trap system. For the present studies, machine imperfections in the quadrupole focusing lattice are considered, which are emulated by adding small random noise on the voltage waveform of the quadrupole electrodes in the Paul trap. It is observed that externally driven noise continuously produces a nonthermal tail of trapped ions, and increases the transverse emittance almost linearly with the duration of themore » noise.« less

  14. Efficacy of an experimental toothpaste containing 5% calcium sodium phosphosilicate in the relief of dentin hypersensitivity: An 8-week randomized study (Study 1).

    PubMed

    Sufi, Farzana; Hall, Claire; Mason, Stephen; Shaw, David; Kennedy, Liam; Gallob, John T

    2016-04-01

    To evaluate the efficacy of an experimental toothpaste containing 5% (w/w) calcium sodium phosphosilicate (CSPS) in relieving dentin hypersensitivity (DH) compared with control toothpastes containing no known anti-sensitivity ingredients. This was the first of two exploratory, randomized, four-treatment, examiner-blind, parallel-design, single-site, 8-week studies in healthy subjects with self-reported and clinically diagnosed DH. The experimental toothpaste contained 5% CSPS with a modified surfactant system, developed to enhance its organoleptic properties. Efficacy was evaluated against an abrasivity-matched placebo formulation (0% CSPS) with additional abrasive silica replacing the CSPS, and two commercially available fluoride toothpastes as controls. After an initial lead-in period, subjects were randomized to one of the four study treatments and instructed to brush twice daily for the next 8 weeks. DH was assessed at baseline and following 4 and 8 weeks of treatment by response to tactile and evaporative (air) stimuli, and using a Dentine Hypersensitivity Experience Questionnaire (DHEQ; a validated quality-of-life measure for DH). A total of 134 subjects were randomized and completed the study. All treatments demonstrated statistically significant reductions in sensitivity from baseline at Week 4 and Week 8 for each clinical measure of sensitivity (all P ≤ 0.001). The 0% CSPS toothpaste demonstrated small but statistically significant reductions in Schiff sensitivity score compared with the other study toothpastes at Week 8 (all P< 0.05), whereas the experimental 5% CSPS toothpaste significantly improved the tactile threshold at Week 4 compared with the 0% CSPS toothpaste (P = 0.0467). The DHEQ responses did not reveal any consistent statistically significant within-treatment changes from baseline or between-treatment differences. Correlation analysis showed weak-to-moderate associations between the DHEQ outcomes and clinical endpoints. Study treatments were well tolerated. The treatment differences observed in this exploratory study were small and inconsistent between measures. The reasons for the inconsistencies are not clear but may be related to the properties of the abrasivity-matched 0% CSPS formulation, with the increased level of dental silica conferring an advantage in terms of reducing DH. The ability of dental silicas to occlude exposed dentin tubules and thereby reduce DH has been demonstrated in previous studies, and may warrant further clinical investigation.

  15. The effects of reflexology on pain and sleep deprivation in patients with rheumatoid arthritis: A randomized controlled trial.

    PubMed

    Bakir, Ercan; Baglama, Sevgin Samancioglu; Gursoy, Savas

    2018-05-01

    This study was intended to examine the effect of foot reflexology on RA patients' pain and sleep quality. This is a randomized controlled trial and was held at the "Rheumatology Follow-up Polyclinic" in Turkey between January-July 2015. A total of 60 patients were included in the research. A sociodemographic data form, the Pittsburgh Sleep Quality Index (PSQI) and the Visual Analogue Scale (VAS) were used. Foot Reflexology was administered to the experimental group. The research found that the pain scores of the experimental group were statistically more significant than those of the control group (p < .01). The experimental group's average pain was reduced by the six weeks of foot reflexology. The total PSQI score of the experimental group was lowered. Foot reflexology is a non-pharmacological nursing intervention that may reduce the pain and sleep deprivation symptoms of RA patients. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Randomized test of an implementation intention-based tool to reduce stress-induced eating.

    PubMed

    O'Connor, Daryl B; Armitage, Christopher J; Ferguson, Eamonn

    2015-06-01

    Stress may indirectly contribute to disease (e.g. cardiovascular disease, cancer) by producing deleterious changes to diet. The purpose of this study was to test the effectiveness of a stress management support (SMS) tool to reduce stress-related unhealthy snacking and to promote stress-related healthy snacking. Participants were randomized to complete a SMS tool with instruction to link stressful situations with healthy snack alternatives (experimental) or a SMS tool without a linking instruction (control). On-line daily reports of stressors and snacking were completed for 7 days. Daily stressors were associated with unhealthy snack consumption in the control condition but not in the experimental condition. Participants highly motivated towards healthy eating consumed a greater number of healthy snacks in the experimental condition on stressful days compared to participants in the experimental condition with low and mean levels of motivation. This tool is an effective, theory driven, intervention that helps to protect against stress-induced high-calorie snack consumption.

  17. Modeling Local Interactions during the Motion of Cyanobacteria

    PubMed Central

    Galante, Amanda; Wisen, Susanne; Bhaya, Devaki; Levy, Doron

    2012-01-01

    Synechocystis sp., a common unicellular freshwater cyanobacterium, has been used as a model organism to study phototaxis, an ability to move in the direction of a light source. This microorganism displays a number of additional characteristics such as delayed motion, surface dependence, and a quasi-random motion, where cells move in a seemingly disordered fashion instead of in the direction of the light source, a global force on the system. These unexplained motions are thought to be modulated by local interactions between cells such as intercellular communication. In this paper, we consider only local interactions of these phototactic cells in order to mathematically model this quasi-random motion. We analyze an experimental data set to illustrate the presence of quasi-random motion and then derive a stochastic dynamic particle system modeling interacting phototactic cells. The simulations of our model are consistent with experimentally observed phototactic motion. PMID:22713858

  18. Standard of reporting animal-based experimental research in Indian Journal of Pharmacology.

    PubMed

    Aiman, Umme; Rahman, Syed Ziaur

    2015-01-01

    The objective of present study was to survey and determine the reporting standards of animal studies published during three years from 2012 to 2014 in the Indian Journal of Pharmacology (IJP). All issues of IJP published in the year 2012, 2013 and 2014 were reviewed to identify animal studies. Each animal study was searched for 15 parameters specifically designed to review standards of animal experimentation and research methodology. All published studies had clearly defined aims and objectives while a statement on ethical clearance about the study protocol was provided in 97% of papers. Information about animal strain and sex was given in 91.8% and 90% of papers respectively. Age of experimental animals was mentioned by 44.4% papers while source of animals was given in 50.8% papers. Randomization was reported by 37.4% while 9.9% studies reported blinding. Only 3.5% studies mentioned any limitations of their work. Present study demonstrates relatively good reporting standards in animal studies published in IJP. The items which need to be improved are randomization, blinding, sample size calculation, stating the limitations of study, sources of support and conflict of interest. The knowledge shared in the present paper could be used for better reporting of animal based experiments.

  19. A Randomized Controlled Trial of a Home-Visiting Intervention Aimed at Preventing Relationship Problems in Depressed Mothers and Their Infants

    ERIC Educational Resources Information Center

    van Doesum, Karin T. M.; Riksen-Walraven, J. Marianne; Hosman, Clemens M. H.; Hoefnagels, Cees

    2008-01-01

    This study examined the effect of a mother-baby intervention on the quality of mother-child interaction, infant-mother attachment security, and infant socioemotional functioning in a group of depressed mothers with infants aged 1-12 months. A randomized controlled trial compared an experimental group (n = 35) receiving the intervention (8-10 home…

  20. "Using Data" to Inform Decisions: How Teachers Use Data to Inform Practice and Improve Student Performance in Mathematics. Results from a Randomized Experiment of Program Efficacy

    ERIC Educational Resources Information Center

    Cavalluzzo, Linda; Geraghty, Thomas M.; Steele, Jennifer L.; Holian, Laura; Jenkins, Frank; Alexander, Jane M.; Yamasaki, Kelsey Y.

    2014-01-01

    The purpose of this study is to evaluate, using a randomized experimental design, the efficacy of TERC's "Using Data" program to change teacher behavior and improve student learning outcomes. The "Using Data" intervention provides professional development and technical assistance to teachers to help them use data…

  1. Packet Randomized Experiments for Eliminating Classes of Confounders

    PubMed Central

    Pavela, Greg; Wiener, Howard; Fontaine, Kevin R.; Fields, David A.; Voss, Jameson D.; Allison, David B.

    2014-01-01

    Background Although randomization is considered essential for causal inference, it is often not possible to randomize in nutrition and obesity research. To address this, we develop a framework for an experimental design—packet randomized experiments (PREs), which improves causal inferences when randomization on a single treatment variable is not possible. This situation arises when subjects are randomly assigned to a condition (such as a new roommate) which varies in one characteristic of interest (such as weight), but also varies across many others. There has been no general discussion of this experimental design, including its strengths, limitations, and statistical properties. As such, researchers are left to develop and apply PREs on an ad hoc basis, limiting its potential to improve causal inferences among nutrition and obesity researchers. Methods We introduce PREs as an intermediary design between randomized controlled trials and observational studies. We review previous research that used the PRE design and describe its application in obesity-related research, including random roommate assignments, heterochronic parabiosis, and the quasi-random assignment of subjects to geographic areas. We then provide a statistical framework to control for potential packet-level confounders not accounted for by randomization. Results PREs have successfully been used to improve causal estimates of the effect of roommates, altitude, and breastfeeding on weight outcomes. When certain assumptions are met, PREs can asymptotically control for packet-level characteristics. This has the potential to statistically estimate the effect of a single treatment even when randomization to a single treatment did not occur. Conclusions Applying PREs to obesity-related research will improve decisions about clinical, public health, and policy actions insofar as it offers researchers new insight into cause and effect relationships among variables. PMID:25444088

  2. Histopathological evaluation of the effect of locally administered strontium on healing time in mandibular fractures: An experimental study.

    PubMed

    Durmuş, Kasım; Turgut, Nergiz Hacer; Doğan, Mehtap; Tuncer, Ersin; Özer, Hatice; Altuntaş, Emine Elif; Akyol, Melih

    2017-10-01

    Mandibular fractures are the most common facial fractures. They can be treated by conservative techniques or by surgery. The authors hypothesized that the application of a single local dose of strontium chloride would accelerate the healing of subcondylar mandibular fractures, shorten the recovery time and prevent complications. The aim of the present pilot study was to evaluate the effects of a single local dose of strontium chloride on the healing of subcondylar mandibular fractures in rats. This randomized experimental study was carried out on 24 male Wistar albino rats. The rats were randomly divided into 3 groups: experimental group 1, receiving 3% strontium chloride; experimental group 2, receiving 5% strontium chloride; and the control group. A full thickness surgical osteotomy was created in the subcondylar area. A single dose of strontium solution (0.3 cc/site) was administered locally by injection on the bone surfaces of the fracture line created. Nothing was administered to the control group. The mandibles were dissected on postoperative day 21. The fractured hemimandibles were submitted to histopathological examination. The median bone fracture healing score was 9 (range: 7-9) in experimental group 1; 8 (range: 7-10) in experimental group 2; and 7.50 (range: 7-8) in the control group. When the groups were compared in terms of bone healing scores, there was a statistically significant difference between experimental group 1 and the control group (p < 0.05). This study is the first to show that local strontium may have positive effects on the healing of subcondylar mandibular fractures. In the authors' opinion, 3% strontium was beneficial for accelerating facial skeleton consolidation and bone regeneration in rat subcondylar mandibular fractures. This treatment procedure may be combined with closed fracture treatment or a conservative approach.

  3. Experimental gingivitis, bacteremia and systemic biomarkers: a randomized clinical trial.

    PubMed

    Kinane, D F; Zhang, P; Benakanakere, M; Singleton, J; Biesbrock, A; Nonnenmacher, C; He, T

    2015-12-01

    Bacteremia and systemic inflammatory markers are associated with periodontal and systemic diseases and may be linking mechanisms between these conditions. We hypothesized that in the development of gingival inflammation, systemic markers of inflammation and bacteremia would increase. To study the effect of bacteremia on systemic inflammatory markers, we recruited 80 subjects to participate in an experimental gingivitis study. Subjects were stratified based on gender, smoking and the number of bleeding sites and then randomized to one of two groups: control group (n = 40) or experimental gingivitis group (n = 40). Subjects in the control group conducted an oral hygiene regimen: brushing twice daily with a regular sodium fluoride cavity protection dentifrice and a standard manual toothbrush, flossing twice daily, and mouth rinsing with an anti-cavity fluoride rinse once daily. The experimental group stopped brushing and flossing, and used only the fluoride anti-cavity mouth rinse for 21 d. Seventy-nine of 80 subjects were evaluable. One subject in the control group was excluded from the results due to antibiotic use during the study. Our data showed the experimental gingivitis group exhibited a significant (p < 0.05) increase in dental plaque level and gingival inflammatory indices relative to baseline and the control group but a decrease in bacteremia and soluble intercellular adhesion molecule-1 levels vs. baseline. Bacteremia was negatively correlated with gingival inflammatory indices and soluble intercellular adhesion molecule-1 levels in the experimental gingivitis group, thus negating our hypothesis. We conclude that there are marked differences in systemic cytokine levels over the course of short-term experimentally induced gingivitis and further conclude that a long-term periodontitis study must be considered to address mechanisms whereby oral diseases may affect systemic diseases. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Voice Quality After a Semi-Occluded Vocal Tract Exercise With a Ventilation Mask in Contemporary Commercial Singers: Acoustic Analysis and Self-Assessments.

    PubMed

    Fantini, Marco; Succo, Giovanni; Crosetti, Erika; Borragán Torre, Alfonso; Demo, Roberto; Fussi, Franco

    2017-05-01

    The current study aimed at investigating the immediate effects of a semi-occluded vocal tract exercise with a ventilation mask in a group of contemporary commercial singers. A randomized controlled study was carried out. Thirty professional or semi-professional singers with no voice complaints were randomly divided into two groups on recruitment: an experimental group and a control group. The same warm-up exercise was performed by the experimental group with an occluded ventilation mask placed over the nose and the mouth and by the control group without the ventilation mask. Voice was recorded before and after the exercise. Acoustic and self-assessment analysis were accomplished. The acoustic parameters of the voice samples recorded before and after training were compared, as well as the parameters' variations between the experimental and the control group. Self-assessment results of the experimental and the control group were compared too. Significant changes after the warm-up exercise included jitter, shimmer, and singing power ratio (SPR) in the experimental group. No significant changes were recorded in the control group. Significant differences between the experimental and the control group were found for ΔShimmer and ΔSPR. Self-assessment analysis confirmed a significantly higher phonatory comfort and voice quality perception for the experimental group. The results of the present study support the immediate advantageous effects on singing voice of a semi-occluded vocal tract exercise with a ventilation mask in terms of acoustic quality, phonatory comfort, and voice quality perception in contemporary commercial singers. Long-term effects still remain to be studied. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  5. Neurofeedback Training as a New Method in Treatment of Crystal Methamphetamine Dependent Patients: A Preliminary Study.

    PubMed

    Rostami, R; Dehghani-Arani, F

    2015-09-01

    This study aimed to compare the effectiveness of neurofeedback (NFB) plus pharmacotherapy with pharmacotherapy alone, on addiction severity, mental health, and quality of life in crystal methamphetamine-dependent (CMD) patients. The study included 100 CMD patients undergoing a medical treatment who volunteered for this randomized controlled trial. After being evaluated by a battery of questionnaires that included addiction severity index questionnaire, Symptoms Check List 90 version, and World Health Organization Quality of Life, the participants were randomly assigned to an experimental or a control group. The experimental group received thirty 50-min sessions of NFB in addition to their usual medication over a 2-month period; meanwhile, the control group received only their usual medication. In accordance with this study's pre-test-post-test design, both study groups were evaluated again after completing their respective treatment regimens. Multivariate analysis of covariance showed the experimental group to have lower severity of addiction, better psychological health, and better quality of life in than the control group. The differences between the two groups were statistically significant. These finding suggest that NFB can be used to improve the effectiveness of treatment results in CMD patients.

  6. Experimental sleep restriction causes endothelial dysfunction in healthy humans.

    PubMed

    Calvin, Andrew D; Covassin, Naima; Kremers, Walter K; Adachi, Taro; Macedo, Paula; Albuquerque, Felipe N; Bukartyk, Jan; Davison, Diane E; Levine, James A; Singh, Prachi; Wang, Shihan; Somers, Virend K

    2014-11-25

    Epidemiologic evidence suggests a link between short sleep duration and cardiovascular risk, although the nature of any relationship and mechanisms remain unclear. Short sleep duration has also been linked to an increase in cardiovascular events. Endothelial dysfunction has itself been implicated as a mediator of heightened cardiovascular risk. We sought to determine the effect of 8 days/8 nights of partial sleep restriction on endothelial function in healthy humans. Sixteen healthy volunteers underwent a randomized study of usual sleep versus sleep restriction of two-thirds normal sleep time for 8 days/8 nights in a hospital-based clinical research unit. The main outcome was endothelial function measured by flow-mediated brachial artery vasodilatation (FMD). Those randomized to sleep restriction slept 5.1 hours/night during the experimental period compared with 6.9 hours/night in the control group. Sleep restriction was associated with significant impairment in FMD (8.6±4.6% during the initial pre-randomization acclimation phase versus 5.2±3.4% during the randomized experimental phase, P=0.01) whereas no change was seen in the control group (5.0±3.0 during the acclimation phase versus 6.73±2.9% during the experimental phase, P=0.10) for a between-groups difference of -4.40% (95% CI -7.00 to -1.81%, P=0.003). No change was seen in non-flow mediated vasodilatation (NFMD) in either group. In healthy individuals, moderate sleep restriction causes endothelial dysfunction. ClinicalTrials.gov. Unique identifier: NCT01334788. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  7. Review of research designs and statistical methods employed in dental postgraduate dissertations.

    PubMed

    Shirahatti, Ravi V; Hegde-Shetiya, Sahana

    2015-01-01

    There is a need to evaluate the quality of postgraduate dissertations of dentistry submitted to university in the light of the international standards of reporting. We conducted the review with an objective to document the use of sampling methods, measurement standardization, blinding, methods to eliminate bias, appropriate use of statistical tests, appropriate use of data presentation in postgraduate dental research and suggest and recommend modifications. The public access database of the dissertations from Rajiv Gandhi University of Health Sciences was reviewed. Three hundred and thirty-three eligible dissertations underwent preliminary evaluation followed by detailed evaluation of 10% of randomly selected dissertations. The dissertations were assessed based on international reporting guidelines such as strengthening the reporting of observational studies in epidemiology (STROBE), consolidated standards of reporting trials (CONSORT), and other scholarly resources. The data were compiled using MS Excel and SPSS 10.0. Numbers and percentages were used for describing the data. The "in vitro" studies were the most common type of research (39%), followed by observational (32%) and experimental studies (29%). The disciplines conservative dentistry (92%) and prosthodontics (75%) reported high numbers of in vitro research. Disciplines oral surgery (80%) and periodontics (67%) had conducted experimental studies as a major share of their research. Lacunae in the studies included observational studies not following random sampling (70%), experimental studies not following random allocation (75%), not mentioning about blinding, confounding variables and calibrations in measurements, misrepresenting the data by inappropriate data presentation, errors in reporting probability values and not reporting confidence intervals. Few studies showed grossly inappropriate choice of statistical tests and many studies needed additional tests. Overall observations indicated the need to comply with standard guidelines of reporting research.

  8. Random anisotropy model approach on ion beam sputtered Co 20Cu 80 granular alloy

    NASA Astrophysics Data System (ADS)

    Errahmani, H.; Hassanaı̈n, N.; Berrada, A.; Abid, M.; Lassri, H.; Schmerber, G.; Dinia, A.

    2002-03-01

    The Co 20Cu 80 granular film has been elaborated using ion beam sputtering technique. The magnetic properties of the sample were studied in the temperature range 5-300 K at H⩽50 kOe. From the thermomagnetisation curve, which is found to obey to the Bloch law, we have extracted the spin wave stiffness constant D and the exchange constant A. The magnetic experimental results have been interpreted in the framework of random anisotropy model. We have determined the local anisotropy constant KL and the local correlation length of anisotropy axis Ra, which is compared to the experimental grains size obtained by transmission electronic microscopy.

  9. Low-lying dipole response in the stable 40,48Ca nuclei within the second random-phase approximation

    NASA Astrophysics Data System (ADS)

    Gambacurta, D.; Grasso, M.; Catara, F.

    2012-10-01

    The low-lying dipole strength distributions of 40CaCa and 48Ca, in the energy region between 5 and 10 MeV, are studied within the second random phase approximation (RPA) with Skyrme interaction. Standard RPA models do not usually predict any presence of strength in this energy region, while experimentally a significant amount of strength is found. The inclusion of the 2 particle -2 hole configurations allows to obtain a description in a rather good agreement with the experimental data. The properties of the most collective state are analyzed in terms of its 1 particle -1 hole nature and its transition densities.

  10. Impact of a Plant-Based Diet and Support on Mitigating Type 2 Diabetes Mellitus in Latinos Living in Medically Underserved Areas.

    PubMed

    Ramal, Edelweiss; Champlin, Andrea; Bahjri, Khaled

    2018-03-01

    To determine the impact that a high-fiber, low-fat diet, derived from mostly plant-based sources, when coupled with support has upon self-management of type 2 diabetes mellitus in Latinos from medically underserved areas (MUAs). Experimental randomized controlled community pilot study. Three community clinics in MUAs located within San Bernardino County, California. Thirty-two randomly assigned Latinos with A1 C greater than 6.4: 15 control and 17 experimental. Participants completed a 5-week education program. Researchers provided follow-up support for 17 randomly assigned experimental group participants through focus groups held at participating clinics-1, 3, and 6 months posteducation. Changes in fat and fiber consumption were measured using a modified Dietary Screener for Mexican Americans. Self-management was measured through the Self-Efficacy for Exercise Scale and Diabetes Quality of Life Measure. Baseline characteristics for both groups were analyzed using independent t tests and χ 2 tests. A 2-way repeated-measures analysis of variance was used to analyze biometric data between baseline and 6 months for both groups. Mean A1 C levels decreased from baseline to 6 months for both groups: control, μ 1 = 9.57, μ 2 = 9.49; experimental, μ 1 = 8.53, μ 2 = 7.31. The experimental group demonstrated a statistically significant reduction in mean A1 C levels ( P = .002) when compared to the control group.

  11. The Effects of a Flipped Classroom Model of Instruction on Students' Performance and Attitudes towards Chemistry

    ERIC Educational Resources Information Center

    Olakanmi, Eunice Eyitayo

    2017-01-01

    This study establishes the effects of a flipped classroom model of instruction on academic performance and attitudes of 66 first-year secondary school students towards chemistry. A pre-test and post-test experimental design was employed to assign students randomly into either the experimental or control group. In order to assess the suitability of…

  12. Variation: Use It or Misuse It--Replication and Its Variants

    ERIC Educational Resources Information Center

    Drummond, Gordon B.; Vowler, Sarah L.

    2012-01-01

    In this article, the authors talk about variation and how variation between measurements may be reduced if sampling is not random. They also talk about replication and its variants. A replicate is a repeated measurement from the same experimental unit. An experimental unit is the smallest part of an experiment or a study that can be subject to a…

  13. Effects of Training Method and Gender on Learning 2D/3D Geometry

    ERIC Educational Resources Information Center

    Khairulanuar, Samsudin; Nazre, Abd Rashid; Jamilah, H.; Sairabanu, Omar Khan; Norasikin, Fabil

    2010-01-01

    This article reports the findings of an experimental study involving 36 primary school students (16 girls, 20 boys, Mean age = 9.5 years, age range: 8-10 years) in geometrical understanding of 2D and 3D objects. Students were assigned into two experimental groups and one control group based on a stratified random sampling procedure. The first…

  14. The Effects of Computerized and Traditional Ear Training Programs on Aural Skills of Elementary Students

    ERIC Educational Resources Information Center

    Kariuki, Patrick N.; Ross, Zachary R.

    2017-01-01

    The purpose of this study was to investigate the effects of computerized and traditional ear training methods on the aural skills abilities of elementary music students. The sample consisted of 20 students who were randomly assigned to either an experimental or control group. The experimental group was taught for five sessions using computerized…

  15. The Effects of Strategy Training and an Extrinsic Incentive on Fourth- and Fifth-Grade Students' Performance, Confidence, and Calibration Accuracy

    ERIC Educational Resources Information Center

    Gutierrez de Blume, Antonio P.

    2017-01-01

    This study investigated the influence of strategy training instruction and an extrinsic incentive on American fourth- and fifth-grade students' (N = 35) performance, confidence in performance, and calibration accuracy. Using an experimental design, children were randomized to either an experimental group (strategy training and an extrinsic…

  16. The Effects of Inhalation Aromatherapy on Anxiety in Patients With Myocardial Infarction: A Randomized Clinical Trial

    PubMed Central

    Najafi, Zahra; Taghadosi, Mohsen; Sharifi, Khadijeh; Farrokhian, Alireza; Tagharrobi, Zahra

    2014-01-01

    Background: Anxiety is an important mental health problem in patients with cardiac disease. Anxiety reduces patients’ quality of life and increases the risk of different cardiac complications. Objectives: The aim of this study was to investigate the effects of inhalation aromatherapy on anxiety in patients with myocardial infarction. Patients and Methods: This was a randomized clinical trial conduced on 68 patients with myocardial infarction hospitalized in coronary care units of a large-scale teaching hospital affiliated to Kashan University of Medical Sciences, Kashan, Iran in 2013. By using the block randomization technique, patients were randomly assigned to experimental (33 patients receiving inhalation aromatherapy with lavender aroma twice a day for two subsequent days) and control (35 patients receiving routine care of study setting including no aromatherapy) groups. At the beginning of study and twenty minutes after each aromatherapy session, anxiety state of patients was assessed using the Spielberger’s State Anxiety Inventory. Data was analyzed using SPSS v. 16.0. We used Chi-square, Fisher’s exact, independent-samples T-test and repeated measures analysis of variance to analyze the study data. Results: The study groups did not differ significantly regarding baseline anxiety mean and demographic characteristics. However, after the administration of aromatherapy, anxiety mean in the experimental group was significantly lower than the control group. Conclusions: Inhalation aromatherapy with lavender aroma can reduce anxiety in patients with myocardial infarction. Consequently, healthcare providers, particularly nurses, can use this strategy to improve postmyocardial infarction anxiety management. PMID:25389481

  17. Epidemiologic methods in clinical trials.

    PubMed

    Rothman, K J

    1977-04-01

    Epidemiologic methods developed to control confounding in non-experimental studies are equally applicable for experiments. In experiments, most confounding is usually controlled by random allocation of subjects to treatment groups, but randomization does not preclude confounding except for extremely large studies, the degree of confounding expected being inversely related to the size of the treatment groups. In experiments, as in non-experimental studies, the extent of confounding for each risk indicator should be assessed, and if sufficiently large, controlled. Confounding is properly assessed by comparing the unconfounded effect estimate to the crude effect estimate; a common error is to assess confounding by statistical tests of significance. Assessment of confounding involves its control as a prerequisite. Control is most readily and cogently achieved by stratification of the data, though with many factors to control simultaneously, multivariate analysis or a combination of multivariate analysis and stratification might be necessary.

  18. Effects of live sax music on various physiological parameters, pain level, and mood level in cancer patients: a randomized controlled trial.

    PubMed

    Burrai, Francesco; Micheluzzi, Valentina; Bugani, Valentina

    2014-01-01

    Few randomized controlled trial studies have focused on the effect of music in cancer patients, and there are no randomized controlled trials on the effects of live music with saxophone in cancer patients. To determine the effects of live saxophone music on various physiological parameters, pain level, and mood level. A randomized controlled trial study. 52 cancer patients were randomized to a control group (n = 26), an experimental group (n = 26) whose members received 30 minutes of live music therapy with saxophone. Systolic and diastolic blood pressure, pulse rate, glycemia, oxygen saturation, pain level, and mood level were measured before and after the live music performance. There was a statistical difference between the groups for oxygen saturation (0.003) and mood level (0.001). Live music performed with a saxophone could be introduced in oncology care to improve the oxygen saturation and mood in cancer patients.

  19. A comparative study of restricted randomization procedures for multiarm trials with equal or unequal treatment allocation ratios.

    PubMed

    Ryeznik, Yevgen; Sverdlov, Oleksandr

    2018-06-04

    Randomization designs for multiarm clinical trials are increasingly used in practice, especially in phase II dose-ranging studies. Many new methods have been proposed in the literature; however, there is lack of systematic, head-to-head comparison of the competing designs. In this paper, we systematically investigate statistical properties of various restricted randomization procedures for multiarm trials with fixed and possibly unequal allocation ratios. The design operating characteristics include measures of allocation balance, randomness of treatment assignments, variations in the allocation ratio, and statistical characteristics such as type I error rate and power. The results from the current paper should help clinical investigators select an appropriate randomization procedure for their clinical trial. We also provide a web-based R shiny application that can be used to reproduce all results in this paper and run simulations under additional user-defined experimental scenarios. Copyright © 2018 John Wiley & Sons, Ltd.

  20. Does the patient‐held record improve continuity and related outcomes in cancer care: a systematic review

    PubMed Central

    Gysels, Marjolein; Richardson, Alison; Higginson, Irene J.

    2006-01-01

    Abstract Objectives  To assess the effectiveness of the patient‐held record (PHR) in cancer care. Background  Patients with cancer may receive care from different services resulting in gaps. A PHR could provide continuity and patient involvement in care. Search strategy  Relevant literature was identified through five electronic databases (Medline, Embase, Cinahl, CCTR and CDSR) and hand searches. Inclusion criteria  Patient‐held records in cancer care with the purpose of improving communication and information exchange between and within different levels of care and to promote continuity of care and patients’ involvement in their own care. Data extraction and synthesis  Data extraction recorded characteristics of intervention, type of study and factors that contributed to methodological quality of individual studies. Data were then contrasted by setting, objectives, population, study design, outcome measures and changes in outcome, including knowledge, satisfaction, anxiety and depression. Methodological quality of randomized control trials and non‐experimental studies were assessed with separate standard grading scales. Main results and conclusions  Seven randomized control trials and six non‐experimental studies were identified. Evaluations of the PHR have reached equivocal findings. Randomized trials found an absence of effect, non‐experimental evaluations shed light on the conditions for its successful use. Most patients welcomed introduction of a PHR. Main problems related to its suitability for different patient groups and the lack of agreement between patients and health professionals regarding its function. Further research is required to determine the conditions under which the PHR can realize its potential as a tool to promote continuity of care and patient participation. PMID:17324196

  1. Generation of a tunable environment for electrical oscillator systems.

    PubMed

    León-Montiel, R de J; Svozilík, J; Torres, Juan P

    2014-07-01

    Many physical, chemical, and biological systems can be modeled by means of random-frequency harmonic oscillator systems. Even though the noise-free evolution of harmonic oscillator systems can be easily implemented, the way to experimentally introduce, and control, noise effects due to a surrounding environment remains a subject of lively interest. Here, we experimentally demonstrate a setup that provides a unique tool to generate a fully tunable environment for classical electrical oscillator systems. We illustrate the operation of the setup by implementing the case of a damped random-frequency harmonic oscillator. The high degree of tunability and control of our scheme is demonstrated by gradually modifying the statistics of the oscillator's frequency fluctuations. This tunable system can readily be used to experimentally study interesting noise effects, such as noise-induced transitions in systems driven by multiplicative noise, and noise-induced transport, a phenomenon that takes place in quantum and classical coupled oscillator networks.

  2. Women's experiences as members of attention control and experimental intervention groups in a randomized controlled trial.

    PubMed

    Beal, Claudia C; Stuifbergen, Alexa; Volker, Deborah; Becker, Heather

    2009-12-01

    Attention control groups are often used in research testing the efficacy of psychosocial and behavioural interventions in order to control for placebo effects. The authors conducted a descriptive qualitative study to investigate how participants viewed their experiences in attention control and experimental intervention groups following a randomized controlled trial for women with fibromyalgia syndrome. Moderately structured interviews were conducted with 18 women (12 from the experimental intervention group and 6 from the attention control group). Members of the control group reported some benefits but few behavioural changes as a result of participating in the RCT, and some participants expressed disappointment at not receiving the intervention. Perceptions of changes in attitudes towards fibromyalgia syndrome and behaviours reported by the intervention group appear to be consistent with the theory underlying the intervention. Possible placebo effects identified in both groups include negative and positive social interactions with other participants.

  3. The effect of foot reflexology on physiologic parameters and mechanical ventilation weaning time in patients undergoing open-heart surgery: A clinical trial study.

    PubMed

    Ebadi, Abbas; Kavei, Parastoo; Moradian, Seyyed Tayyeb; Saeid, Yaser

    2015-08-01

    The aim of this study was to investigate the efficacy of foot reflexology on physiological parameters and mechanical ventilation weaning time in patients undergoing open-heart surgery. This was a double blind three-group randomized controlled trial. Totally, 96 patients were recruited and randomly allocated to the experimental, placebo, and the control groups. Study groups respectively received foot reflexology, simple surface touching, and the routine care of the study setting. Physiological parameters (pulse rate, respiratory rate, systolic and diastolic blood pressures, mean arterial pressure, percutaneous oxygen saturation) and weaning time were measured. The study groups did not differ significantly in terms of physiological parameters (P value > 0.05). However, the length of weaning time in the experimental group was significantly shorter than the placebo and the control groups (P value < 0.05). The study findings demonstrated the efficiency of foot reflexology in shortening the length of weaning time. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. 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.

  5. A randomized, controlled, single-blind, 6-month pilot study to evaluate the efficacy of MS-Line!: a cognitive rehabilitation programme for patients with multiple sclerosis.

    PubMed

    Gich, Jordi; Freixanet, Jordi; García, Rafael; Vilanova, Joan Carles; Genís, David; Silva, Yolanda; Montalban, Xavier; Ramió-Torrentà, Lluís

    2015-09-01

    MS-Line! was created to provide an effective treatment for cognitive impairment in multiple sclerosis (MS) patients. To assess the efficacy of MS-Line!. A randomized, controlled, single-blind, 6-month pilot study. Patients were randomly assigned to an experimental group (cognitive rehabilitation with the programme) or to a control group (no cognitive rehabilitation). Randomization was stratified by cognitive impairment level. Cognitive assessment included: selective reminding test, 10/36 spatial recall test (10/36 SPART), symbol digit modalities test, paced auditory serial addition test, word list generation (WLG), FAS test, subtests of WAIS-III, Boston naming test (BNT), and trail making test (TMT). Forty-three patients (22 in the experimental group, 21 in the control group) were analyzed. Covariance analysis showed significant differences in 10/36 SPART (P=0.0002), 10/36 SPART delayed recall (P=0.0021), WLG (P=0.0123), LNS (P=0.0413), BNT (P=0.0007) and TMT-A (P=0.010) scores between groups. The study showed a significant improvement related to learning and visual memory, executive functions, attention and information processing speed, and naming ability in those patients who received cognitive rehabilitation. The results suggest that MS-Line! is effective in improving cognitive impairment in MS patients. © The Author(s), 2015.

  6. Mirror therapy for distal radial fractures: A pilot randomized controlled study.

    PubMed

    Bayon-Calatayud, Manuel; Benavente-Valdepeñas, Ana Maria; Del Prado Vazquez-Muñoz, Maria

    2016-10-12

    To investigate the efficacy of mirror therapy in reducing pain and disability in patients with distal radial fractures. Pilot randomized controlled study. Twenty-two patients with closed distal radial fracture. Patients were randomly assigned to experimental (= 11) or control (= 11) groups. Researchers were blinded to group allocation. Both groups received conventional physiotherapy. In addition, the experimental group had 15 sessions of mirror therapy (a daily session, 30 min). The control group received the same amount of conventional occupational therapy. Assessment was made from baseline to post-treatment. Pain was measured on a visual analogue scale (VAS). Active wrist extension and Quick-DASH (Disabilities of Arm, Shoulder and Hand) were used to assess functional recovery. Pain, disability, and range of motion improved for both groups after intervention. No significant post-treatment differences were found between groups in Quick-DASH (= 0.409), active wrist extension (= 0.191) and VAS scores (= 0.807). There was no significant difference in active wrist extension between groups. Mirror therapy was not superior to conventional occupational therapy in reducing pain and disability.

  7. From Planning to Implementation: An Examination of Changes in the Research Design, Sample Size, and Precision of Group Randomized Trials Launched by the Institute of Education Sciences

    ERIC Educational Resources Information Center

    Spybrook, Jessaca; Puente, Anne Cullen; Lininger, Monica

    2013-01-01

    This article examines changes in the research design, sample size, and precision between the planning phase and implementation phase of group randomized trials (GRTs) funded by the Institute of Education Sciences. Thirty-eight GRTs funded between 2002 and 2006 were examined. Three studies revealed changes in the experimental design. Ten studies…

  8. Determining the Effects That the Order of Abstraction and Type of Reflection Have on Content Knowledge When Teaching Experientially: An Exploratory Experiment

    ERIC Educational Resources Information Center

    Baker, Marshall A.; Brown, Nicholas R.; Blackburn, J. Joey; Robinson, J. Shane

    2014-01-01

    The purpose of this experimental study was to determine the effects of order of abstraction and type of reflection on student knowledge acquisition. Students were assigned randomly to one of four treatment combinations in the completely randomized 2 x 2 design which included either abstraction prior to or directly after an experience, and either…

  9. The Impact of Supplemental Handwriting and Spelling Instruction with First Grade Students Who Do Not Acquire Transcription Skills as Rapidly as Peers: A Randomized Control Trial

    ERIC Educational Resources Information Center

    Graham, Steve; Harris, Karen R.; Adkins, Mary

    2018-01-01

    The impact of supplemental handwriting and spelling instruction on learning to write was examined in an experimental study with first grade students who were not acquiring these skills as rapidly as their classmates. Thirty students (16 boys, 14 girls) were randomly assigned to a handwriting and spelling instructional condition or a phonological…

  10. Response of space shuttle insulation panels to acoustic noise pressure

    NASA Technical Reports Server (NTRS)

    Vaicaitis, R.

    1976-01-01

    The response of reusable space shuttle insulation panels to random acoustic pressure fields are studied. The basic analytical approach in formulating the governing equations of motion uses a Rayleigh-Ritz technique. The input pressure field is modeled as a stationary Gaussian random process for which the cross-spectral density function is known empirically from experimental measurements. The response calculations are performed in both frequency and time domain.

  11. Survival distributions impact the power of randomized placebo-phase design and parallel groups randomized clinical trials.

    PubMed

    Abrahamyan, Lusine; Li, Chuan Silvia; Beyene, Joseph; Willan, Andrew R; Feldman, Brian M

    2011-03-01

    The study evaluated the power of the randomized placebo-phase design (RPPD)-a new design of randomized clinical trials (RCTs), compared with the traditional parallel groups design, assuming various response time distributions. In the RPPD, at some point, all subjects receive the experimental therapy, and the exposure to placebo is for only a short fixed period of time. For the study, an object-oriented simulation program was written in R. The power of the simulated trials was evaluated using six scenarios, where the treatment response times followed the exponential, Weibull, or lognormal distributions. The median response time was assumed to be 355 days for the placebo and 42 days for the experimental drug. Based on the simulation results, the sample size requirements to achieve the same level of power were different under different response time to treatment distributions. The scenario where the response times followed the exponential distribution had the highest sample size requirement. In most scenarios, the parallel groups RCT had higher power compared with the RPPD. The sample size requirement varies depending on the underlying hazard distribution. The RPPD requires more subjects to achieve a similar power to the parallel groups design. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Continuous time quantum random walks in free space

    NASA Astrophysics Data System (ADS)

    Eichelkraut, Toni; Vetter, Christian; Perez-Leija, Armando; Christodoulides, Demetrios; Szameit, Alexander

    2014-05-01

    We show theoretically and experimentally that two-dimensional continuous time coherent random walks are possible in free space, that is, in the absence of any external potential, by properly tailoring the associated initial wave function. These effects are experimentally demonstrated using classical paraxial light. Evidently, the usage of classical beams to explore the dynamics of point-like quantum particles is possible since both phenomena are mathematically equivalent. This in turn makes our approach suitable for the realization of random walks using different quantum particles, including electrons and photons. To study the spatial evolution of a wavefunction theoretically, we consider the one-dimensional paraxial wave equation (i∂z +1/2 ∂x2) Ψ = 0 . Starting with the initially localized wavefunction Ψ (x , 0) = exp [ -x2 / 2σ2 ] J0 (αx) , one can show that the evolution of such Gaussian-apodized Bessel envelopes within a region of validity resembles the probability pattern of a quantum walker traversing a uniform lattice. In order to generate the desired input-field in our experimental setting we shape the amplitude and phase of a collimated light beam originating from a classical HeNe-Laser (633 nm) utilizing a spatial light modulator.

  13. Quasi-experimental study designs series-paper 1: introduction: two historical lineages.

    PubMed

    Bärnighausen, Till; Røttingen, John-Arne; Rockers, Peter; Shemilt, Ian; Tugwell, Peter

    2017-09-01

    The objective of this study was to contrast the historical development of experiments and quasi-experiments and provide the motivation for a journal series on quasi-experimental designs in health research. A short historical narrative, with concrete examples, and arguments based on an understanding of the practice of health research and evidence synthesis. Health research has played a key role in developing today's gold standard for causal inference-the randomized controlled multiply blinded trial. Historically, allocation approaches developed from convenience and purposive allocation to alternate and, finally, to random allocation. This development was motivated both by concerns for manipulation in allocation as well as statistical and theoretical developments demonstrating the power of randomization in creating counterfactuals for causal inference. In contrast to the sequential development of experiments, quasi-experiments originated at very different points in time, from very different scientific perspectives, and with frequent and long interruptions in their methodological development. Health researchers have only recently started to recognize the value of quasi-experiments for generating novel insights on causal relationships. While quasi-experiments are unlikely to replace experiments in generating the efficacy and safety evidence required for clinical guidelines and regulatory approval of medical technologies, quasi-experiments can play an important role in establishing the effectiveness of health care practice, programs, and policies. The papers in this series describe and discuss a range of important issues in utilizing quasi-experimental designs for primary research and quasi-experimental results for evidence synthesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Effects of interactive visual feedback training on post-stroke pusher syndrome: a pilot randomized controlled study.

    PubMed

    Yang, Yea-Ru; Chen, Yi-Hua; Chang, Heng-Chih; Chan, Rai-Chi; Wei, Shun-Hwa; Wang, Ray-Yau

    2015-10-01

    We investigated the effects of a computer-generated interactive visual feedback training program on the recovery from pusher syndrome in stroke patients. Assessor-blinded, pilot randomized controlled study. A total of 12 stroke patients with pusher syndrome were randomly assigned to either the experimental group (N = 7, computer-generated interactive visual feedback training) or control group (N = 5, mirror visual feedback training). The scale for contraversive pushing for severity of pusher syndrome, the Berg Balance Scale for balance performance, and the Fugl-Meyer assessment scale for motor control were the outcome measures. Patients were assessed pre- and posttraining. A comparison of pre- and posttraining assessment results revealed that both training programs led to the following significant changes: decreased severity of pusher syndrome scores (decreases of 4.0 ± 1.1 and 1.4 ± 1.0 in the experimental and control groups, respectively); improved balance scores (increases of 14.7 ± 4.3 and 7.2 ± 1.6 in the experimental and control groups, respectively); and higher scores for lower extremity motor control (increases of 8.4 ± 2.2 and 5.6 ± 3.3 in the experimental and control groups, respectively). Furthermore, the computer-generated interactive visual feedback training program produced significantly better outcomes in the improvement of pusher syndrome (p < 0.01) and balance (p < 0.05) compared with the mirror visual feedback training program. Although both training programs were beneficial, the computer-generated interactive visual feedback training program more effectively aided recovery from pusher syndrome compared with mirror visual feedback training. © The Author(s) 2014.

  15. A randomized control study of psychological intervention to reduce anxiety, amotivation and psychological distress among medical students

    PubMed Central

    Saravanan, Coumaravelou; Kingston, Rajiah

    2014-01-01

    Background: Test anxiety aggravates psychological distress and reduces the motivation among graduate students. This study aimed to identify psychological intervention for test anxiety, which reduces the level of psychological distress, amotivation and increases the intrinsic and extrinsic motivation among medical students. Materials and Methods: Westside test anxiety scale, Kessler Perceived Stress Scale and Academic Motivation Scale were used to measure test anxiety, psychological distress and motivation on 436 1st year medical students. Out of 436 students, 74 students who exhibited moderate to high test anxiety were randomly divided into either experimental or waiting list group. In this true randomized experimental study, 32 participants from the intervention group received five sessions of psychological intervention consist of psychoeducation, relaxation therapy and systematic desensitization. Thirty-three students from waiting list received one session of advice and suggestions. Results: After received psychological intervention participants from the intervention group experienced less anxiety, psychological distress, and amotivation (P < 0.01) and high intrinsic and extrinsic motivation (P < 0.01) in the postassessment compared with their preassessment scores. Conclusion: Overall psychological intervention is effective to reduce anxiety scores and its related variables. PMID:25097619

  16. The preliminary effect of a parenting program for Korean American mothers: a randomized controlled experimental study.

    PubMed

    Kim, Eunjung; Cain, Kevin C; Webster-Stratton, Carolyn

    2008-09-01

    Traditional Korean American discipline is characterized by a lack of expression of affection and use of harsh discipline. The purpose of this study was to pilot test the effect of the Incredible Years Parenting Program among Korean American mothers. A randomized controlled experimental study design was used; 29 first-generation Korean American mothers of young children (3-8 years old) were randomly assigned to intervention (n=20) and control (n=9) groups. Intervention group mothers received a 12-week parenting program. Control group mothers did not receive the intervention. Mothers reported on discipline styles (positive, appropriate, and harsh), level of acculturation, and their child's outcomes (behavioral problems and social competence) at pre-, post-, and 1-year follow-up intervals. After completing the program, intervention group mothers significantly increased use of positive discipline as compared to control group mothers. Among intervention group mothers, high-acculturated mothers significantly increased appropriate discipline whereas low-acculturated mothers significantly decreased harsh discipline. In the 1-year follow-up, intervention group mothers maintained the significant effect for positive discipline. Providing this program appears to be a promising way of promoting positive discipline among Korean American mothers.

  17. The effects of mirror therapy on the gait of subacute stroke patients: a randomized controlled trial.

    PubMed

    Ji, Sang Gu; Kim, Myoung Kwon

    2015-04-01

    To investigate the effect of mirror therapy on the gait of patients with subacute stroke. Randomized controlled experimental study. Outpatient rehabilitation hospital. Thirty-four patients with stroke were randomly assigned to two groups: a mirror therapy group (experimental) and a control group. The stroke patients in the experimental group underwent comprehensive rehabilitation therapy and mirror therapy for the lower limbs. The stroke patients in the control group underwent sham therapy and comprehensive rehabilitation therapy. Participants in both groups received therapy five days per week for four weeks. Temporospatial gait characteristics, such as single stance, stance phase, step length, stride, swing phase, velocity, and cadence, were assessed before and after the four weeks therapy period. A significant difference was observed in post-training gains for the single stance (10.32 SD 4.14 vs. 6.54 SD 3.23), step length (8.47 SD 4.12 vs. 4.83 SD 2.14), and stride length (17.03 SD 6.57 vs 10.54 SD 4.34) between the experimental group and the control group (p < 0.05). However, there were no significant differences between two groups on stance phase, swing phase, velocity, cadence, and step width (P > 0.05). We conclude that mirror therapy may be beneficial in improving the effects of stroke on gait ability. © The Author(s) 2014.

  18. Block randomization versus complete randomization of human perception stimuli: is there a difference?

    NASA Astrophysics Data System (ADS)

    Moyer, Steve; Uhl, Elizabeth R.

    2015-05-01

    For more than 50 years, the U.S. Army RDECOM CERDEC Night Vision and Electronic Sensors Directorate (NVESD) has been studying and modeling the human visual discrimination process as it pertains to military imaging systems. In order to develop sensor performance models, human observers are trained to expert levels in the identification of military vehicles. From 1998 until 2006, the experimental stimuli were block randomized, meaning that stimuli with similar difficulty levels (for example, in terms of distance from target, blur, noise, etc.) were presented together in blocks of approximately 24 images but the order of images within the block was random. Starting in 2006, complete randomization came into vogue, meaning that difficulty could change image to image. It was thought that this would provide a more statistically robust result. In this study we investigated the impact of the two types of randomization on performance in two groups of observers matched for skill to create equivalent groups. It is hypothesized that Soldiers in the Complete Randomized condition will have to shift their decision criterion more frequently than Soldiers in the Block Randomization group and this shifting is expected to impede performance so that Soldiers in the Block Randomized group perform better.

  19. High-Speed Device-Independent Quantum Random Number Generation without a Detection Loophole

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Yuan, Xiao; Li, Ming-Han; Zhang, Weijun; Zhao, Qi; Zhong, Jiaqiang; Cao, Yuan; Li, Yu-Huai; Chen, Luo-Kan; Li, Hao; Peng, Tianyi; Chen, Yu-Ao; Peng, Cheng-Zhi; Shi, Sheng-Cai; Wang, Zhen; You, Lixing; Ma, Xiongfeng; Fan, Jingyun; Zhang, Qiang; Pan, Jian-Wei

    2018-01-01

    Quantum mechanics provides the means of generating genuine randomness that is impossible with deterministic classical processes. Remarkably, the unpredictability of randomness can be certified in a manner that is independent of implementation devices. Here, we present an experimental study of device-independent quantum random number generation based on a detection-loophole-free Bell test with entangled photons. In the randomness analysis, without the independent identical distribution assumption, we consider the worst case scenario that the adversary launches the most powerful attacks against the quantum adversary. After considering statistical fluctuations and applying an 80 Gb ×45.6 Mb Toeplitz matrix hashing, we achieve a final random bit rate of 114 bits /s , with a failure probability less than 10-5. This marks a critical step towards realistic applications in cryptography and fundamental physics tests.

  20. Affectionate Writing Reduces Total Cholesterol: Two Randomized, Controlled Trials

    ERIC Educational Resources Information Center

    Floyd, Kory; Mikkelson, Alan C.; Hesse, Colin; Pauley, Perry M.

    2007-01-01

    In two 5-week trials, healthy college students were randomly assigned either to experimental or control groups. Participants in the experimental groups wrote about their affection for significant friends, relatives, and/or romantic partners for 20 minutes on three separate occasions; on the same schedule, those in the control groups wrote about…

  1. Efficacy of an experimental toothpaste containing 5% calcium sodium phosphosilicate in the relief of dentin hypersensitivity: An 8-week randomized study (Study 2).

    PubMed

    Sufi, Farzana; Hall, Claire; Mason, Stephen; Shaw, David; Milleman, Jeffery; Milleman, Kimberly

    2016-04-01

    To compare the efficacy of an experimental toothpaste containing 5% (w/w) calcium sodium phosphosilicate (CSPS) in relieving dentin hypersensitivity (DH) with that of control toothpastes containing no known anti-sensitivity ingredients. This was the second of two exploratory, randomized, four-treatment, examiner-blind, parallel-design, single-site, 8-week studies in healthy subjects with self-reported and clinically diagnosed DH. After an initial lead-in period, subjects were randomized to one of four study treatments: the experimental toothpaste containing 5% CSPS with a modified surfactant system, developed to enhance its organoleptic properties; an abrasivity-matched placebo formulation (0% CSPS) with additional abrasive silica replacing the CSPS; or one of two commercially available fluoride toothpastes as controls. Subjects were instructed to brush twice daily for the next 8 weeks. DH was assessed at baseline and following 4 and 8 weeks of treatment by response to tactile and evaporative (air) stimuli, and using a Dentine Hypersensitivity Experience Questionnaire (DHEQ; a validated quality of life measure for DH). A total of 137 subjects were included in the efficacy analysis. The experimental 5% CSPS toothpaste demonstrated statistically significant reductions from baseline in sensitivity at Week 4 and Week 8 for each clinical measure (all P< 0.01). It also demonstrated significantly greater improvements in DH compared with the two control toothpastes for the majority of clinical measures at Week 4 (P ≤ 0.01) and for all clinical measures at Week 8 (all P < 0.01). The abrasivity-matched 0% CSPS toothpaste was associated with similar outcomes to the 5% CSPS toothpaste. The DHEQ responses did not reveal any consistent statistically significant within-treatment changes from baseline or between-treatment differences. Strong correlations with DHEQ outcomes were only observed for the subjects' sensitivity rating in response to evaporative (air) stimuli at Week 8. Study treatments were well tolerated.

  2. Online gambling's moderators: how effective? Study protocol for a randomized controlled trial.

    PubMed

    Caillon, Julie; Grall-Bronnec, Marie; Hardouin, Jean-Benoit; Venisse, Jean-Luc; Challet-Bouju, Gaelle

    2015-05-30

    Online gambling has been legalized in France in 2010. Licenses are issued to gambling operators who demonstrate their ability to respect the legal framework (security, taxation, consumer protection, etc.). The preventive measures to protect vulnerable gamblers include an obligation to provide online gambling moderators. These moderators should allow gamblers to limit their bets, exclude themselves from the website for 7 days, and consult the balance of the gambler's account at any time. However, there are only a few published reports of empirical research investigating the effectiveness of Internet-based protective measures implemented by French law. Moreover, no empirical research has yet studied the impact of bonuses on gambling behaviors. This research is an experimental randomized controlled trial, risk prevention targeted. The research is divided into four sub-studies depending on the studied moderator: limiting bonuses, self-exclusion, self-limitation and information. The study sample consists of 485 volunteers. For each experimental condition and the control groups, the sample is composed of gamblers equally recruited from gamblers having preferences in each of the three major forms of games (lottery and scratch tickets, sports and horserace betting, and poker). For each form of gambling, the gamblers are recruited in order to obtain as many problem gamblers as non-problem gamblers. According to the randomization, the experimental session begins. The experimental session is a gambling situation on a computer in our research center. The gambler is invited to play on his favorite gambling site as usual, with his own gambler account and his own money. Data collected comprise sociodemographic characteristics, gambling habits, an interview about enjoyment and feeling out of control during the gambling session, moderator impact on gambling practice, statement of gambling parameters and questionnaires (BMIS, GRCS, CPGI, GACS). Moderator efficiency is assessed based on the two major characteristics of gambling behavior: money wagered and time spent in gambling. The results of this research will be important to prevent online problem gambling and influence policy-makers. NCT01789580. Registered 8 February 2013.

  3. Fatigue failure of materials under broad band random vibrations

    NASA Technical Reports Server (NTRS)

    Huang, T. C.; Lanz, R. W.

    1971-01-01

    The fatigue life of material under multifactor influence of broad band random excitations has been investigated. Parameters which affect the fatigue life are postulated to be peak stress, variance of stress and the natural frequency of the system. Experimental data were processed by the hybrid computer. Based on the experimental results and regression analysis a best predicting model has been found. All values of the experimental fatigue lives are within the 95% confidence intervals of the predicting equation.

  4. Use of Portfolio Assessment Technique in Teaching Map Sketching and Location in Secondary School Geography in Jos, Nigeria

    ERIC Educational Resources Information Center

    Ugodulunwa, Christiana; Wakjissa, Sayita

    2015-01-01

    This study investigated the use of portfolio assessment technique in teaching map sketching and location in geography in Jos, Nigeria. It adopted a quasi-experimental design. Two schools were selected using a table of random numbers from a population of 51 schools in Jos South and assigned to each of experimental and control group. The…

  5. "Learning to Become a Family Caregiver" Efficacy of an Intervention Program for Caregivers Following Diagnosis of Dementia in a Relative

    ERIC Educational Resources Information Center

    Ducharme, Francine C.; Levesque, Louise L.; Lachance, Lise M.; Kergoat, Marie-Jeanne; Legault, Alain J.; Beaudet, Line M.; Zarit, Steven H.

    2011-01-01

    Purpose: The purpose of this experimental study was to test the efficacy of a psychoeducational individual program conceived to facilitate transition to the caregiver role following diagnosis of Alzheimer disease in a relative. Design and Methods: Caregivers were recruited in memory clinics and randomized to an experimental group (n = 62) or a…

  6. Effectiveness of Mutual Learning Approach in the Academic Achievement of B.Ed Students in Learning Optional II English

    ERIC Educational Resources Information Center

    Arulselvi, Evangelin

    2013-01-01

    The present study aims at finding out the effectiveness of Mutual learning approach over the conventional method in learning English optional II among B.Ed students. The randomized pre-test, post test, control group and experimental group design was employed. The B.Ed students of the same college formed the control and experimental groups. Each…

  7. Project Clarion: Three Years of Science Instruction in Title I Schools among K-Third Grade Students

    ERIC Educational Resources Information Center

    Kim, Kyung Hee; VanTassel-Baska, Joyce; Bracken, Bruce A.; Feng, Annie; Stambaugh, Tamra; Bland, Lori

    2012-01-01

    The purpose of the study was to measure the effects of higher level, inquiry-based science curricula on students at primary level in Title I schools. Approximately 3,300 K-3 students from six schools were assigned to experimental or control classes (N = 115 total) on a random basis according to class. Experimental students were exposed to…

  8. An Evaluation of the Effectiveness of the Remediation Plus Program on Improving Reading Achievement of Students in the Marinette (WI) School District

    ERIC Educational Resources Information Center

    Corcoran, Roisin P.; Ross, Steven M.

    2015-01-01

    The study was implemented in the Title I Marinette School District using a randomized experimental design and parallel quasi experimental design spanning three grades 1-3 in 3 district elementary schools. The Remediation Plus Intervention is a multi-sensory, systematic synthetic phonics curriculum for all ages of students who struggle with…

  9. Evaluation of the effect of cryotherapy in preventing oral mucositis associated with chemotherapy - a randomized controlled trial.

    PubMed

    Katrancı, Nilgün; Ovayolu, Nimet; Ovayolu, Ozlem; Sevinc, Alper

    2012-09-01

    The goal of this study was to assess the effect of oral cryotherapy on the development of oral mucositis related to infusion of 5-fluorouracil (5-FU) with leucovorin. This study, a randomized controlled trial with random assignments to the experimental and control groups, was conducted with cancer patients. The study included 60 patients; 30 patients in the study group were instructed to hold ice cubes in their mouth shortly before, during, and shortly after infusion of 5-FU with leucovorin, the 30 patients in the control group received routine care. Oral mucositis in the patients was evaluated at 7, 14, and 21 days after chemotherapy. For analysis of data, chi-square, Fisher's tests were used; p < 0.05 was accepted as statistically significant. In the majority of patients receiving cryotherapy, oral mucositis was not observed (Grade 0) at 7 and 14 days. Similarly, incidence of Grades 1, 2, and 3 oral mucositis in the experimental group was quite a bit lower when compared to the control group (p < 0.05). On day 21, no statistically significant difference between the experimental and control groups was determined based on the development of oral mucositis (p > 0.05). We found that oral cryotherapy has a significant contribution to the protection of oral health by reducing mucositis score according to the WHO mucositis scale, especially on the 7th and 14th days. Nurses' awareness of how cryotherapy can affect patients and options for resolving problems will enable them to provide a higher standard of individualized care. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Effects of online games on student performance in undergraduate physics

    NASA Astrophysics Data System (ADS)

    Sadiq, Irfan

    The present state of physics teaching and learning is a reflection of the difficulty of the subject matter which has resulted in students' low motivation toward physics as well as lack of meaningful and deeper learning experiences. In light of an overall decline in interest in physics, an investigation of alternate teaching and learning methods and tools was appropriate. The research posed the following question: To what extent do online games about kinematics and two-dimensional motion impact student performance in undergraduate general physics as measured by a unit posttest? Two intact classes of 20 students each were randomly assigned to either the experimental group or the control group. Only the experimental group received the treatment of using online games. The duration of topics covered in the game content was identical to the lecture on kinematics and two-dimensional motion. Instructors for the experimental group incorporated online games in their regular classroom teaching, whereas those in the control group continued with their previously used curriculum without games. This study was conducted in three weekly sessions. Although students were not selected using random sampling, existing classes were randomly assigned to either the experimental group or the control group. There were 20 students in the experimental group and 20 students in the control group. The independent samples t test was conducted to compare the means of two independently sampled experimental and control groups. Analysis of covariance (ANCOVA) was used to determine if the two groups were significantly different with regard to their general physics performance on the posttest while controlling for the pretest scores. Analysis of posttest and pretest scores revealed that game-based learning did not significantly impact student performance.

  11. Core stabilization exercise with real-time feedback for chronic hemiparetic stroke: a pilot randomized controlled trials.

    PubMed

    Chung, Eunjung; Lee, Byoung-Hee; Hwang, Sujin

    2014-01-01

    The purpose of this study was to examine the feasibility of core stabilization exercise with real-time feedback on balance and gait function in patients with chronic hemiparetic stroke. Nineteen stroke subjects were enrolled in this study. The patients were randomly divided into the experimental (n = 10) and control groups (n = 9). Subjects in the experimental group performed core stabilization exercise with real-time feedback training for 30 minutes per day during a period of six weeks. Subjects in the control group performed core stabilization exercise during the same period. This study assessed the kinematic parameters using a portable walkway system, and timed up-and-go test. Gait velocity showed significantly greater improvement in the experimental group (7.3 ± 5.0 sec) than in the control group (-0.7 ± 10.6). Stride length showed significantly greater increase in the experimental group (13.2 ± 7.9 on the affected side and 12.6 ± 8.0 on the less affected side) than the control group (3.5 ± 8.7 on the affected side and 3.4 ± 8.5 on the less affected side). After training, change in results on the timed up and go test was significantly greater in the experimental group than in the control group. Core stabilization exercise using real-time feedback produces greater improvement in gait performance in chronic hemiparetic stroke patients than core stabilization exercise only.

  12. Effects of vibration and shock on the performance of gas-bearing space-power Brayton cycle turbomachinery. Part 3: Sinusoidal and random vibration data reduction and evaluation, and random vibration probability analysis

    NASA Technical Reports Server (NTRS)

    Tessarzik, J. M.; Chiang, T.; Badgley, R. H.

    1973-01-01

    The random vibration response of a gas bearing rotor support system has been experimentally and analytically investigated in the amplitude and frequency domains. The NASA Brayton Rotating Unit (BRU), a 36,000 rpm, 10 KWe turbogenerator had previously been subjected in the laboratory to external random vibrations, and the response data recorded on magnetic tape. This data has now been experimentally analyzed for amplitude distribution and magnetic tape. This data has now been experimentally analyzed for amplitude distribution and frequency content. The results of the power spectral density analysis indicate strong vibration responses for the major rotor-bearing system components at frequencies which correspond closely to their resonant frequencies obtained under periodic vibration testing. The results of amplitude analysis indicate an increasing shift towards non-Gaussian distributions as the input level of external vibrations is raised. Analysis of axial random vibration response of the BRU was performed by using a linear three-mass model. Power spectral densities, the root-mean-square value of the thrust bearing surface contact were calculated for specified input random excitation.

  13. Simvastatin as an Adjunct to Conventional Therapy of Non-infectious Uveitis: A Randomized, Open-Label Pilot Study.

    PubMed

    Shirinsky, Ivan V; Biryukova, Anastasia A; Shirinsky, Valery S

    2017-12-01

    Statins have been shown to reduce ocular inflammation in animal models of uveitis and to prevent development of uveitis in observational studies. There have been no experimental human studies evaluating statins' efficacy and safety in uveitis. In this study, we aimed to investigate efficacy and safety of simvastatin in patients with uveitis. For this single-center, open-label, randomized study, we enrolled patients with acute non-infectious uveitis. The patients were randomized to receive 40 mg simvastatin per day for 2 months in addition to conventional treatment or conventional treatment alone. The studied outcomes were the rate of steroid-sparing control of ocular inflammation, measures of ocular inflammation, intraocular pressure, and visual acuity. Fifty patients were enrolled in the study. Twenty-five patients were randomly assigned to receive simvastatin with conventional treatment and 25 to conventional treatment alone. Simvastatin was associated with significantly higher rates of steroid-sparing ocular inflammation control, decrease in anterior chamber inflammation, and improvement in visual acuity. The treatment was well tolerated, no serious adverse effects were observed. Our findings suggest that statins may have therapeutic potential in uveitis. These results need to be confirmed in double-blind, randomized, controlled studies.

  14. Cognitive behavioral therapy program for cannabis use cessation in first-episode psychosis patients: study protocol for a randomized controlled trial.

    PubMed

    González-Ortega, Itxaso; Echeburúa, Enrique; García-Alocén, Adriana; Vega, Patricia; González-Pinto, Ana

    2016-07-29

    The high rate of cannabis use among patients with first-episode psychosis (FEP), as well as the associated negative impact on illness course and treatment outcomes, underlines the need for effective interventions in these populations. However, to date, there have been few clinical treatment trials (of pharmacological or psychological interventions) that have specifically focused on addressing comorbid cannabis use among these patients. The aim of this paper is to describe the design of a study protocol for a randomized controlled trial in which the objective is to assess the efficacy of a specific cognitive behavioral therapy program for cannabis cessation in patients with FEP compared to standard treatment (psychoeducation). This is a single-blind randomized study with 1 year of follow-up. Patients are to be randomly assigned to one of two treatments: (1) specific cognitive behavioral therapy for cannabis cessation composed of 1-hour sessions once a week for 16 weeks, in addition to pharmacological treatment scheduled by the psychiatrist, or (2) a control group (psychoeducation + pharmacological treatment) following the same format as the experimental group. Participants in both groups will be evaluated at baseline (pre-treatment), at 16 weeks (post-treatment), and at 3 and 6 months and 1 year of follow-up. The primary outcome will be that patients in the experimental group will have greater cannabis cessation than patients in the control group at post-treatment. The secondary outcome will be that the experimental group will have better clinical and functional outcomes than the control group. This study provides the description of a clinical trial design based on specific cognitive behavioral therapy for cannabis cessation in FEP patients, aiming to improve clinical and functional outcome, as well as tackling the addictive disorder. NCT02319746 ClinicalTrials.gov Identifier. ClinicalTrials.gov Protocol and Results Registration System (PRS) Receipt Release Date: 15 December 2014.

  15. Flexible random lasers with tunable lasing emissions.

    PubMed

    Lee, Ya-Ju; Chou, Chun-Yang; Yang, Zu-Po; Nguyen, Thi Bich Hanh; Yao, Yung-Chi; Yeh, Ting-Wei; Tsai, Meng-Tsan; Kuo, Hao-Chun

    2018-04-19

    In this study, we experimentally demonstrated a flexible random laser fabricated on a polyethylene terephthalate (PET) substrate with a high degree of tunability in lasing emissions. Random lasing oscillation arises mainly from the resonance coupling between the emitted photons of gain medium (Rhodamine 6G, R6G) and the localized surface plasmon (LSP) of silver nanoprisms (Ag NPRs), which increases the effective cross-section for multiple light scattering, thus stimulating the lasing emissions. More importantly, it was found that the random lasing wavelength is blue-shifted monolithically with the increase in bending strains exerted on the PET substrate, and a maximum shift of ∼15 nm was achieved in the lasing wavelength, when a 50% bending strain was exerted on the PET substrate. Such observation is highly repeatable and reversible, and this validates that we can control the lasing wavelength by simply bending the flexible substrate decorated with the Ag NPRs. The scattering spectrum of the Ag NPRs was obtained using a dark-field microscope to understand the mechanism for the dependence of the wavelength shift on the exerted bending strains. As a result, we believe that the experimental demonstration of tunable lasing emissions based on the revealed structure is expected to open up a new application field of random lasers.

  16. Random field assessment of nanoscopic inhomogeneity of bone

    PubMed Central

    Dong, X. Neil; Luo, Qing; Sparkman, Daniel M.; Millwater, Harry R.; Wang, Xiaodu

    2010-01-01

    Bone quality is significantly correlated with the inhomogeneous distribution of material and ultrastructural properties (e.g., modulus and mineralization) of the tissue. Current techniques for quantifying inhomogeneity consist of descriptive statistics such as mean, standard deviation and coefficient of variation. However, these parameters do not describe the spatial variations of bone properties. The objective of this study was to develop a novel statistical method to characterize and quantitatively describe the spatial variation of bone properties at ultrastructural levels. To do so, a random field defined by an exponential covariance function was used to present the spatial uncertainty of elastic modulus by delineating the correlation of the modulus at different locations in bone lamellae. The correlation length, a characteristic parameter of the covariance function, was employed to estimate the fluctuation of the elastic modulus in the random field. Using this approach, two distribution maps of the elastic modulus within bone lamellae were generated using simulation and compared with those obtained experimentally by a combination of atomic force microscopy and nanoindentation techniques. The simulation-generated maps of elastic modulus were in close agreement with the experimental ones, thus validating the random field approach in defining the inhomogeneity of elastic modulus in lamellae of bone. Indeed, generation of such random fields will facilitate multi-scale modeling of bone in more pragmatic details. PMID:20817128

  17. Cluster-Glass Phase in Pyrochlore X Y Antiferromagnets with Quenched Disorder

    NASA Astrophysics Data System (ADS)

    Andrade, Eric C.; Hoyos, José A.; Rachel, Stephan; Vojta, Matthias

    2018-03-01

    We study the impact of quenched disorder (random exchange couplings or site dilution) on easy-plane pyrochlore antiferromagnets. In the clean system, order by disorder selects a magnetically ordered state from a classically degenerate manifold. In the presence of randomness, however, different orders can be chosen locally depending on details of the disorder configuration. Using a combination of analytical considerations and classical Monte Carlo simulations, we argue that any long-range-ordered magnetic state is destroyed beyond a critical level of randomness where the system breaks into magnetic domains due to random exchange anisotropies, becoming, therefore, a glass of spin clusters, in accordance with the available experimental data. These random anisotropies originate from off-diagonal exchange couplings in the microscopic Hamiltonian, establishing their relevance to other magnets with strong spin-orbit coupling.

  18. Asymmetrically dominated choice problems, the isolation hypothesis and random incentive mechanisms.

    PubMed

    Cox, James C; Sadiraj, Vjollca; Schmidt, Ulrich

    2014-01-01

    This paper presents an experimental study of the random incentive mechanisms which are a standard procedure in economic and psychological experiments. Random incentive mechanisms have several advantages but are incentive-compatible only if responses to the single tasks are independent. This is true if either the independence axiom of expected utility theory or the isolation hypothesis of prospect theory holds. We present a simple test of this in the context of choice under risk. In the baseline (one task) treatment we observe risk behavior in a given choice problem. We show that by integrating a second, asymmetrically dominated choice problem in a random incentive mechanism risk behavior can be manipulated systematically. This implies that the isolation hypothesis is violated and the random incentive mechanism does not elicit true preferences in our example.

  19. Spline methods for approximating quantile functions and generating random samples

    NASA Technical Reports Server (NTRS)

    Schiess, J. R.; Matthews, C. G.

    1985-01-01

    Two cubic spline formulations are presented for representing the quantile function (inverse cumulative distribution function) of a random sample of data. Both B-spline and rational spline approximations are compared with analytic representations of the quantile function. It is also shown how these representations can be used to generate random samples for use in simulation studies. Comparisons are made on samples generated from known distributions and a sample of experimental data. The spline representations are more accurate for multimodal and skewed samples and to require much less time to generate samples than the analytic representation.

  20. Phase Diagram of a Three-Dimensional Antiferromagnet with Random Magnetic Anisotropy

    DOE PAGES

    Perez, Felio A.; Borisov, Pavel; Johnson, Trent A.; ...

    2015-03-04

    Three-dimensional (3D) antiferromagnets with random magnetic anisotropy (RMA) that were experimentally studied to date have competing two-dimensional and three-dimensional exchange interactions which can obscure the authentic effects of RMA. The magnetic phase diagram of Fe xNi 1-xF 2 epitaxial thin films with true random single-ion anisotropy was deduced from magnetometry and neutron scattering measurements and analyzed using mean field theory. Regions with uniaxial, oblique and easy plane anisotropies were identified. A RMA-induced glass region was discovered where a Griffiths-like breakdown of long-range spin order occurs.

  1. Mode detuning in systems of weakly coupled oscillators

    NASA Astrophysics Data System (ADS)

    Spencer, Ross L.; Robertson, Richard D.

    2001-11-01

    A system of weakly magnetically coupled oscillating blades is studied experimentally, computationally, and theoretically. It is found that when the uncoupled natural frequencies of the blades are nearly equal, the normal modes produced by the coupling are almost impossible to find experimentally if the random variation level in the system parameters is on the order of (or larger than) the relative differences between mode frequencies. But if the uncoupled natural frequencies are made to vary (detuned) in a smooth way such that the total relative spread in natural frequency exceeds the random variations, normal modes are rather easy to find. And if the detuned uncoupled frequencies of the system are parabolically distributed, the modes are found to be shaped like Hermite functions.

  2. Low-lying dipole response in the stable {sup 40,48}Ca nuclei within the second random-phase approximation

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

    Gambacurta, D.; Grasso, M.; Catara, F.

    2012-10-20

    The low-lying dipole strength distributions of {sup 40}CaCa and {sup 48}Ca, in the energy region between 5 and 10 MeV, are studied within the second random phase approximation (RPA) with Skyrme interaction. Standard RPA models do not usually predict any presence of strength in this energy region, while experimentally a significant amount of strength is found. The inclusion of the 2 particle -2 hole configurations allows to obtain a description in a rather good agreement with the experimental data. The properties of the most collective state are analyzed in terms of its 1 particle -1 hole nature and its transitionmore » densities.« less

  3. Association of funding and conclusions in randomized drug trials: a reflection of treatment effect or adverse events?

    PubMed

    Als-Nielsen, Bodil; Chen, Wendong; Gluud, Christian; Kjaergard, Lise L

    2003-08-20

    Previous studies indicate that industry-sponsored trials tend to draw proindustry conclusions. To explore whether the association between funding and conclusions in randomized drug trials reflects treatment effects or adverse events. Observational study of 370 randomized drug trials included in meta-analyses from Cochrane reviews selected from the Cochrane Library, May 2001. From a random sample of 167 Cochrane reviews, 25 contained eligible meta-analyses (assessed a binary outcome; pooled at least 5 full-paper trials of which at least 1 reported adequate and 1 reported inadequate allocation concealment). The primary binary outcome from each meta-analysis was considered the primary outcome for all trials included in each meta-analysis. The association between funding and conclusions was analyzed by logistic regression with adjustment for treatment effect, adverse events, and additional confounding factors (methodological quality, control intervention, sample size, publication year, and place of publication). Conclusions in trials, classified into whether the experimental drug was recommended as the treatment of choice or not. The experimental drug was recommended as treatment of choice in 16% of trials funded by nonprofit organizations, 30% of trials not reporting funding, 35% of trials funded by both nonprofit and for-profit organizations, and 51% of trials funded by for-profit organizations (P<.001; chi2 test). Logistic regression analyses indicated that funding, treatment effect, and double blinding were the only significant predictors of conclusions. Adjusted analyses showed that trials funded by for-profit organizations were significantly more likely to recommend the experimental drug as treatment of choice (odds ratio, 5.3; 95% confidence interval, 2.0-14.4) compared with trials funded by nonprofit organizations. This association did not appear to reflect treatment effect or adverse events. Conclusions in trials funded by for-profit organizations may be more positive due to biased interpretation of trial results. Readers should carefully evaluate whether conclusions in randomized trials are supported by data.

  4. Marginalized Women in West Iran

    PubMed

    Malmir, Shabnam; Barati, Majid; Khani Jeihooni, Ali; Bashirian, Saeed; Hazavehei, Seyed Mohammad Mehdi

    2018-03-27

    Objective: This study aimed to determine the effectiveness of an educational intervention to prevent cervical cancer among marginalized Iranianwomen based on the Protection Motivation Theory (PMT) as a theoretical framework. Methods: This quasi-experimental study was carried out on 143 women of Kermanshah City in western Iran during 2017. Participants were recruited through cluster and simple random sampling and randomly divided into experimental (n=72) and control groups (n=71). All completed a self-administered questionnaire including PMT constructs and demographic variables. An intervention over six sessions was then applied to the experimental group. Reassessment was conducted three months after the intervention, with data was analyzed with SPSS-16 using chi-square, McNemar, paired T- and independent T-tests. Results: The mean scores for the constructs of PMT, and cervical cancer screening behavior showed no significant differences between the two groups before the intervention (P>0.05). The educational manipulation had significant effects on the experimental groups’ average response for perceived vulnerability, perceived severity, perceived reward, self-efficacy, response efficacy, response cost and protection motivation (all p < 0.001). Also, the prevalence of regular Pap smear testing and referral to health centers were significantly increased after 3 months in the experimental (P=0.048), but notthe control group (P>0.05). Conclusions: The results show that applying an educational intervention based on PMT might help prevent cervical cancer and improve regular Pap smear testing. Creative Commons Attribution License

  5. The effects of trunk stabilization exercise on bone density after menopause.

    PubMed

    Kang, Jeong-Il; Jeong, Dae-Keun; Choi, Hyun

    2015-12-01

    [Purpose] This study examined the effect of low intensity exercise on bone density by conducting trunk stabilization exercise on females after menopause for 24 weeks. [Subjects and Methods] Thirty three female subjects over 47 years old and under the age of 53 were selected and 16 for experimental group and 17 for control group were randomly selected. Experimental group had performed spinal and pelvic stabilization exercise 30 minutes a day, 5times a week, for 24 weeks. Except for the daily life, control group did not participate in any characteristic movement. Bone density of every member in experimental group was measured using average value of bone density of 1st-4th lumbar through quantitative computer tomography. [Results] There was a meaningful difference in only control group about measured value of bone density within each group, experimental and control group, but there was no meaningful difference in measured value of bone density between two groups, experimental group and control group. [Conclusion] Through this research, we could see the fact that although trunk stability exercise could not change bone density meaningfully, it could maintain bone density. In the future, it is randomly necessary to study things related this because results of researches can show different results according to exercise intensity, exercise period, age, weight, hormone status and mediation period. It is considered that it will help to prevent and treat patients with osteoporosis a lot.

  6. Sample size determinations for group-based randomized clinical trials with different levels of data hierarchy between experimental and control arms.

    PubMed

    Heo, Moonseong; Litwin, Alain H; Blackstock, Oni; Kim, Namhee; Arnsten, Julia H

    2017-02-01

    We derived sample size formulae for detecting main effects in group-based randomized clinical trials with different levels of data hierarchy between experimental and control arms. Such designs are necessary when experimental interventions need to be administered to groups of subjects whereas control conditions need to be administered to individual subjects. This type of trial, often referred to as a partially nested or partially clustered design, has been implemented for management of chronic diseases such as diabetes and is beginning to emerge more commonly in wider clinical settings. Depending on the research setting, the level of hierarchy of data structure for the experimental arm can be three or two, whereas that for the control arm is two or one. Such different levels of data hierarchy assume correlation structures of outcomes that are different between arms, regardless of whether research settings require two or three level data structure for the experimental arm. Therefore, the different correlations should be taken into account for statistical modeling and for sample size determinations. To this end, we considered mixed-effects linear models with different correlation structures between experimental and control arms to theoretically derive and empirically validate the sample size formulae with simulation studies.

  7. Triadic Gaze Intervention for Young Children with Physical Disabilities

    PubMed Central

    Olswang, Lesley B.; Dowden, Patricia; Feuerstein, Julie; Greenslade, Kathryn; Pinder, Gay Lloyd; Fleming, Kandace

    2018-01-01

    Purpose This randomized controlled study investigated whether a supplemental treatment designed to teach triadic gaze (TG) as a signal of coordinated joint attention (CJA) would yield a significantly greater increase in TG in the experimental versus control group. Method Eighteen 10- to 24-month-old children with severe motor impairments were randomly assigned to an experimental (n=9) or control group (n=9). For approximately 29 sessions over 17 weeks, experimental participants received TG treatment twice weekly with a speech-language pathologist (SLP) in addition to standard practice. Controls received only standard practice from birth-to-three therapists. Coders masked to group assignment coded TG productions with an unfamiliar SLP at baseline, every three weeks during the experimental phase, and at the final measurement session. Results TG increased across groups from baseline to final measurement, with the experimental group showing slightly greater change. Performance trends were examined using experimental phase moving averages. Comparisons revealed significant differences between groups at two time points (at 12 weeks, r= .30, a medium effect and at the end of the phase r=.50, large effect). Conclusion Results suggest the promise of a short-term, focused treatment to teach TG as a behavioral manifestation of CJA to children with severe physical disabilities. PMID:24686825

  8. High intensity acoustic tests of a thermally stressed aluminum plate in TAFA

    NASA Technical Reports Server (NTRS)

    Ng, Chung Fai; Clevenson, Sherman A.

    1989-01-01

    An investigation was conducted in the Thermal Acoustic Fatigue Apparatus at the Langley Research Center to study the acoustically excited random motion of an aluminum plate which is buckled due to thermal stresses. The thermal buckling displacements were measured and compared with theory. The general trends of the changes in resonances frequencies and random responses of the plate agree with previous theoretical prediction and experimental results for a mechanically buckled plate.

  9. Effects of a Physical Education-Based Programme on Health-Related Physical Fitness and Its Maintenance in High School Students: A Cluster-Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Mayorga-Vega, Daniel; Montoro-Escaño, Jorge; Merino-Marban, Rafael; Viciana, Jesús

    2016-01-01

    The purpose of this study was to examine the effects of a physical education-based development and maintenance programme on objective and perceived health-related physical fitness in high school students. A sample of 111 students aged 12-14 years old from six classes were cluster-randomly assigned to an experimental group (n = 54) or a control…

  10. Effects of group songwriting on motivation and readiness for treatment on patients in detoxification: a randomized wait-list effectiveness study.

    PubMed

    Silverman, Michael J

    2012-01-01

    Songwriting is a commonly utilized music therapy technique for clients in substance abuse rehabilitation. For these patients, motivation and readiness for treatment remain two key treatment areas. Moreover, there is a lack of randomized and controlled music therapy studies systematically investigating how group songwrit-ing can affect patients on a detoxification unit. The purposes of this study were to measure the effects of a single group songwriting session on motivation and readiness for treatment and determine emerging themes from patient-composed songs with patients on a detoxification unit. Participants (N = 99) were randomized to experimental (posttest only) or wait-list control (pretest only) conditions to provide treatment to all participants in an inclusive single-session design. There were significant between-group differences in motivation and readiness for treatment, with experimental participants having higher means than control participants. Code categorizations from patients' composed song lyrics concerned "action," "emotions and feelings," "change," "reflection," "admission," and "responsibility." From the results of this study, it seems that a single group songwriting session can be an effective intervention concerning motivation and readiness for treatment in patients on a detoxification unit. Implications for clinical practice, suggestions for future research, and limitations are provided.

  11. Leisure education reduces stress among older adults.

    PubMed

    Chang, Liang-Chih

    2014-01-01

    The objectives of this study were to examine whether a leisure education program could facilitate leisure competence among older adults and whether it could also reduce their stress. A pre-test-post-test randomized experimental design was conducted. Subjects were randomly assigned to either an experimental group (n = 30) or a control group (n = 30). A leisure education program was used to serve as the intervention. A day before this experiment was carried out, pre-test data were collected using leisure competence and stress scales. Thirty minutes after this experiment ended, post-test data were collected using the same scales. These data were analyzed using an analysis of covariance. The results indicated that the average post-test scores of leisure competence in the experimental group were significantly higher than those in the control group and that the average post-test scores of stress in the experimental group were significantly lower than those in the control group. Healthcare practitioners should adopt the provision of leisure education as a priority to facilitate leisure competence and reduce stress among older adults.

  12. A cluster randomized controlled trial to increase the availability and acceptability of voluntary medical male circumcision in Zambia: The Spear and Shield Project

    PubMed Central

    Weiss, Stephen M; Zulu, Robert; Jones, Deborah L; Redding, Colleen A; Cook, Ryan; Chitalu, Ndashi

    2015-01-01

    Background Widespread voluntary medical male circumcision (VMMC) in Africa could avert an estimated 3·436 million HIV infections and 300,000 deaths over the next 10 years. Most Zambian men, however, have expressed little interest in undergoing VMMC. This study tested the effect of an intervention designed to increase demand for VMMC among these “hard to reach” men. Methods This cluster randomized controlled trial was conducted from 2012 to 2014 in Lusaka, Zambia (HIV prevalence = 20·8%). 13 Community Health Centers (CHCs) were stratified by HIV voluntary counseling and testing (VCT) rates and patient census and randomly assigned (5:5:3) to Experimental, Control or Observation Only conditions. CHC health care providers at all 13 sites received VMMC training. Trial statisticians did not participate in randomization. 800 uncircumcised HIV-, post-VCT men, 400 per condition, were recruited; female partners were invited to participate. The primary outcome was the likelihood of VMMC by 12 months post-intervention. The trial registration is NCT 01688167. Findings 161 participants in the Experimental condition underwent VMMC as compared to 96 Control participants [adjusted odds ratio = 2·45, 95% CI = (1·24, 4·90) p = ·0166]. Post-VMMC condom use among Experimental condition participants increased compared to baseline, with no change among Control participants. No adverse events related to study participation were reported. Interpretation The Spear and Shield intervention combined with VMMC training was associated with a significant increase in the number of VMMCs performed as well as in condom use among “hard to reach” Zambian men. Results support the importance of comprehensive HIV prevention programs that increase supply of and demand for VMMC services. Funding NIH/NIMH R01MH095539. PMID:26120594

  13. Surgical site infections following colorectal cancer surgery: a randomized prospective trial comparing common and advanced antimicrobial dressing containing ionic silver.

    PubMed

    Biffi, Roberto; Fattori, Luca; Bertani, Emilio; Radice, Davide; Rotmensz, Nicole; Misitano, Pasquale; Cenciarelli, Sabine; Chiappa, Antonio; Tadini, Liliana; Mancini, Marina; Pesenti, Giovanni; Andreoni, Bruno; Nespoli, Angelo

    2012-05-23

    An antimicrobial dressing containing ionic silver was found effective in reducing surgical-site infection in a preliminary study of colorectal cancer elective surgery. We decided to test this finding in a randomized, double-blind trial. Adults undergoing elective colorectal cancer surgery at two university-affiliated hospitals were randomly assigned to have the surgical incision dressed with Aquacel Ag Hydrofiber dressing or a common dressing. To blind the patient and the nursing and medical staff to the nature of the dressing used, scrub nurses covered Aquacel Ag Hydrofiber with a common wound dressing in the experimental arm, whereas a double common dressing was applied to patients of control group. The primary end-point of the study was the occurrence of any surgical-site infection within 30 days of surgery. A total of 112 patients (58 in the experimental arm and 54 in the control group) qualified for primary end-point analysis. The characteristics of the patient population and their surgical procedures were similar. The overall rate of surgical-site infection was lower in the experimental group (11.1% center 1, 17.5% center 2; overall 15.5%) than in controls (14.3% center 1, 24.2% center 2, overall 20.4%), but the observed difference was not statistically significant (P = 0.451), even with respect to surgical-site infection grade 1 (superficial) versus grades 2 and 3, or grade 1 and 2 versus grade 3. This randomized trial did not confirm a statistically significant superiority of Aquacel Ag Hydrofiber dressing in reducing surgical-site infection after elective colorectal cancer surgery. Clinicaltrials.gov: NCT00981110.

  14. Depth profiling of high energy nitrogen ions implanted in the <1 0 0>, <1 1 0> and randomly oriented silicon crystals

    NASA Astrophysics Data System (ADS)

    Erić, M.; Petrović, S.; Kokkoris, M.; Lagoyannis, A.; Paneta, V.; Harissopulos, S.; Telečki, I.

    2012-03-01

    This work reports on the experimentally obtained depth profiles of 4 MeV 14N2+ ions implanted in the <1 0 0>, <1 1 0> and randomly oriented silicon crystals. The ion fluence was 1017 particles/cm2. The nitrogen depth profiling has been performed using the Nuclear Reaction Analysis (NRA) method, via the study of 14N(d,α0)12C and 14N(d,α1)12C nuclear reactions, and with the implementation of SRIM 2010 and SIMNRA computer simulation codes. For the randomly oriented silicon crystal, change of the density of silicon matrix and the nitrogen "bubble" formation have been proposed as the explanation for the difference between the experimental and simulated nitrogen depth profiles. During the implantation, the RBS/C spectra were measured on the nitrogen implanted and on the virgin crystal spots. These spectra provide information on the amorphization of the silicon crystals induced by the ion implantation.

  15. Reflections on experimental research in medical education.

    PubMed

    Cook, David A; Beckman, Thomas J

    2010-08-01

    As medical education research advances, it is important that education researchers employ rigorous methods for conducting and reporting their investigations. In this article we discuss several important yet oft neglected issues in designing experimental research in education. First, randomization controls for only a subset of possible confounders. Second, the posttest-only design is inherently stronger than the pretest-posttest design, provided the study is randomized and the sample is sufficiently large. Third, demonstrating the superiority of an educational intervention in comparison to no intervention does little to advance the art and science of education. Fourth, comparisons involving multifactorial interventions are hopelessly confounded, have limited application to new settings, and do little to advance our understanding of education. Fifth, single-group pretest-posttest studies are susceptible to numerous validity threats. Finally, educational interventions (including the comparison group) must be described in detail sufficient to allow replication.

  16. Lingual nerve damage after mandibular third molar surgery: a randomized clinical trial.

    PubMed

    Gomes, Ana Cláudia Amorim; Vasconcelos, Belmiro Cavalcanti do Egito; de Oliveira e Silva, Emanuel Dias; da Silva, Luiz Carlos Ferreira

    2005-10-01

    The objective of this study was to clinically evaluate the frequency, type, and risk factors for lingual nerve damage after mandibular third molar surgery with reference to lingual flap retraction. A total of fifty-five patients referred for bilateral mandibular third molar removal were included in this study. Each patient was randomly allotted to have the procedure performed on 1 side (experimental group) with lingual flap retraction. On the opposite side (control group), the same procedure was performed without lingual flap retraction. Lingual nerve damage occurred in 9.1% in the experimental group in which lingual flap retraction was performed. In the control group, damage to the lingual nerve was not observed. The difference was statistically significant (P <.001) as measured by the Cochran test. Lingual nerve retraction represented a risk factor to temporary lingual nerve damage during mandibular third molar surgery.

  17. A Wave Chaotic Study of Quantum Graphs with Microwave Networks

    NASA Astrophysics Data System (ADS)

    Fu, Ziyuan

    Quantum graphs provide a setting to test the hypothesis that all ray-chaotic systems show universal wave chaotic properties. I study the quantum graphs with a wave chaotic approach. Here, an experimental setup consisting of a microwave coaxial cable network is used to simulate quantum graphs. Some basic features and the distributions of impedance statistics are analyzed from experimental data on an ensemble of tetrahedral networks. The random coupling model (RCM) is applied in an attempt to uncover the universal statistical properties of the system. Deviations from RCM predictions have been observed in that the statistics of diagonal and off-diagonal impedance elements are different. Waves trapped due to multiple reflections on bonds between nodes in the graph most likely cause the deviations from universal behavior in the finite-size realization of a quantum graph. In addition, I have done some investigations on the Random Coupling Model, which are useful for further research.

  18. High-Speed Device-Independent Quantum Random Number Generation without a Detection Loophole.

    PubMed

    Liu, Yang; Yuan, Xiao; Li, Ming-Han; Zhang, Weijun; Zhao, Qi; Zhong, Jiaqiang; Cao, Yuan; Li, Yu-Huai; Chen, Luo-Kan; Li, Hao; Peng, Tianyi; Chen, Yu-Ao; Peng, Cheng-Zhi; Shi, Sheng-Cai; Wang, Zhen; You, Lixing; Ma, Xiongfeng; Fan, Jingyun; Zhang, Qiang; Pan, Jian-Wei

    2018-01-05

    Quantum mechanics provides the means of generating genuine randomness that is impossible with deterministic classical processes. Remarkably, the unpredictability of randomness can be certified in a manner that is independent of implementation devices. Here, we present an experimental study of device-independent quantum random number generation based on a detection-loophole-free Bell test with entangled photons. In the randomness analysis, without the independent identical distribution assumption, we consider the worst case scenario that the adversary launches the most powerful attacks against the quantum adversary. After considering statistical fluctuations and applying an 80  Gb×45.6  Mb Toeplitz matrix hashing, we achieve a final random bit rate of 114  bits/s, with a failure probability less than 10^{-5}. This marks a critical step towards realistic applications in cryptography and fundamental physics tests.

  19. The Medical and Endovascular Treatment of Atherosclerotic Renal Artery Stenosis (METRAS) study: rationale and study design.

    PubMed

    Rossi, G P; Seccia, T M; Miotto, D; Zucchetta, P; Cecchin, D; Calò, L; Puato, M; Motta, R; Caielli, P; Vincenzi, M; Ramondo, G; Taddei, S; Ferri, C; Letizia, C; Borghi, C; Morganti, A; Pessina, A C

    2012-08-01

    It is unclear whether revascularization of renal artery stenosis (RAS) by means of percutaneous renal angioplasty and stenting (PTRAS) is advantageous over optimal medical therapy. Hence, we designed a randomized clinical trial based on an optimized patient selection strategy and hard experimental endpoints. Primary objective of this study is to determine whether PTRAS is superior or equivalent to optimal medical treatment for preserving glomerular filtration rate (GFR) in the ischemic kidney as assessed by 99mTcDTPA sequential renal scintiscan. Secondary objectives of this study are to establish whether the two treatments are equivalent in lowering blood pressure, preserving overall renal function and regressing target organ damage, preventing cardiovascular events and improving quality of life. The study is designed as a prospective multicentre randomized, un-blinded two-arm study. Eligible patients will have clinical and angio-CT evidence of RAS. Inclusion criteria is RAS affecting the main renal artery or its major branches either >70% or, if <70, with post-stenotic dilatation. Renal function will be assessed with 99mTc-DTPA renal scintigraphy. Patients will be randomized to either arms considering both resistance index value in the ischemic kidney and the presence of unilateral/bilateral stenosis. Primary experimental endpoint will be the GFR of the ischemic kidney, assessed as quantitative variable by 99TcDTPA, and the loss of ischemic kidney defined as a categorical variable.

  20. Random electric field instabilities of relaxor ferroelectrics

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

    Arce-Gamboa, Jose R.; Guzman-Verri, Gian G.

    Relaxor ferroelectrics are complex oxide materials which are rather unique to study the effects of compositional disorder on phase transitions. Here, we study the effects of quenched cubic random electric fields on the lattice instabilities that lead to a ferroelectric transition and show that, within a microscopic model and a statistical mechanical solution, even weak compositional disorder can prohibit the development of long-range order and that a random field state with anisotropic and power-law correlations of polarization emerges from the combined effect of their characteristic dipole forces and their inherent charge disorder. As a result, we compare and reproduce severalmore » key experimental observations in the well-studied relaxor PbMg 1/3Nb 2/3O 3–PbTiO 3.« less

  1. Random electric field instabilities of relaxor ferroelectrics

    DOE PAGES

    Arce-Gamboa, Jose R.; Guzman-Verri, Gian G.

    2017-06-13

    Relaxor ferroelectrics are complex oxide materials which are rather unique to study the effects of compositional disorder on phase transitions. Here, we study the effects of quenched cubic random electric fields on the lattice instabilities that lead to a ferroelectric transition and show that, within a microscopic model and a statistical mechanical solution, even weak compositional disorder can prohibit the development of long-range order and that a random field state with anisotropic and power-law correlations of polarization emerges from the combined effect of their characteristic dipole forces and their inherent charge disorder. As a result, we compare and reproduce severalmore » key experimental observations in the well-studied relaxor PbMg 1/3Nb 2/3O 3–PbTiO 3.« less

  2. The Effectiveness of the "Lions Quest Program: Skills for Growing" on School Climate, Students' Behaviors, Perceptions of School, and Conflict Resolution Skills

    ERIC Educational Resources Information Center

    Gol-Guven, Mine

    2017-01-01

    This study examines the effectiveness of the Lions Quest Program: Skills for Growing by employing a quasi-experimental design with a control group. The experimental and control group each comprises two primary schools--one public, one private. One classroom at each grade level, 1 through 4, in each school was selected by random sampling for a…

  3. Clinical Investigation Program, RCS MED-300 (RI).

    DTIC Science & Technology

    1984-10-01

    temperature/dry. Technical Approach: 1) Experimental desion: a post-test only, equivalent - group experimental design will be used in this study. Random...5650 * It. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE Commander October 1984 Dwight David Eisenhower Army Medical Center 1s. NUMBEROFPAGES...Fort Gordon, Georgia 30905-5650 210 14. MONITORING AGENCY NAME I ADORESS(11 different from Controlling Offce) IS. SECURITY CLASS. (of tAle MP*H

  4. Cortical Dynamics in Presence of Assemblies of Densely Connected Weight-Hub Neurons

    PubMed Central

    Setareh, Hesam; Deger, Moritz; Petersen, Carl C. H.; Gerstner, Wulfram

    2017-01-01

    Experimental measurements of pairwise connection probability of pyramidal neurons together with the distribution of synaptic weights have been used to construct randomly connected model networks. However, several experimental studies suggest that both wiring and synaptic weight structure between neurons show statistics that differ from random networks. Here we study a network containing a subset of neurons which we call weight-hub neurons, that are characterized by strong inward synapses. We propose a connectivity structure for excitatory neurons that contain assemblies of densely connected weight-hub neurons, while the pairwise connection probability and synaptic weight distribution remain consistent with experimental data. Simulations of such a network with generalized integrate-and-fire neurons display regular and irregular slow oscillations akin to experimentally observed up/down state transitions in the activity of cortical neurons with a broad distribution of pairwise spike correlations. Moreover, stimulation of a model network in the presence or absence of assembly structure exhibits responses similar to light-evoked responses of cortical layers in optogenetically modified animals. We conclude that a high connection probability into and within assemblies of excitatory weight-hub neurons, as it likely is present in some but not all cortical layers, changes the dynamics of a layer of cortical microcircuitry significantly. PMID:28690508

  5. Clinical Knowledge from Observational Studies: Everything You Wanted to Know but Were Afraid to Ask.

    PubMed

    Gershon, Andrea S; Jafarzadeh, S Reza; Wilson, Kevin C; Walkey, Allan J

    2018-05-07

    Well-done randomized trials provide accurate estimates of treatment effect by producing groups that are similar on all measures except for the intervention of interest. However, inferences of efficacy in tightly-controlled experimental settings may not translate into similar effectiveness in real-world settings. Observational studies generally enable inferences over a wider range of patient characteristics and evaluation of a broader range of outcomes over a longer period than randomized trials. However, clinicians are often reluctant to incorporate the findings of observational studies into clinical practice. Reason for uncertainty regarding observational studies include a lack of familiarity with observational research methods, occasional disagreements between results of observational studies and randomized trials, the perceived risk of spurious results from systematic bias, and prior teaching that randomized trials are the most reliable source of medical evidence. We propose that a better understanding of observational research will enhance clinicians' ability to distinguish reliable observational studies from those that are subjected to biases and, therefore, provide more confidence to apply observational research results into clinical practice when appropriate. Herein, we explain why observational studies may be perceived as less conclusive than randomized trials, address situations in which observational research and randomized trials produced different findings, and provide information on observational study design so that quality can be evaluated. We conclude that observational research is a valuable source of medical evidence and that clinical action is strongest when supported by both high quality observational studies and randomized trials.

  6. Experimental studies of two-stage centrifugal dust concentrator

    NASA Astrophysics Data System (ADS)

    Vechkanova, M. V.; Fadin, Yu M.; Ovsyannikov, Yu G.

    2018-03-01

    The article presents data of experimental results of two-stage centrifugal dust concentrator, describes its design, and shows the development of a method of engineering calculation and laboratory investigations. For the experiments, the authors used quartz, ceramic dust and slag. Experimental dispersion analysis of dust particles was obtained by sedimentation method. To build a mathematical model of the process, dust collection was built using central composite rotatable design of the four factorial experiment. A sequence of experiments was conducted in accordance with the table of random numbers. Conclusion were made.

  7. Experimental evaluation of the effects of drug information on antibiotic prescribing: a study in outpatient care in an area of Sri lanka.

    PubMed

    Angunawela, I I; Diwan, V K; Tomson, G

    1991-06-01

    The intervention level of epidemiology is useful for studying effects in health systems research. Due to practical and ethical reasons, it is often difficult to apply experimental methods such as classical randomized clinical trials in the field. However with alternative approaches such as 'randomization by group' some of these problems can be overcome. Drug information has since long been considered as an instrument to influence physicians, however evaluation of its effects is a new field of research. In the present study the impact of drug information on prescribing behaviour was evaluated in an outpatient setting in Sri Lanka. The study included 15 state health institutions (45 prescribers) with a common drug formulary. Groups of prescribers were randomized into two interventions; newsletters and newsletters reinforced by a group seminar, and one control group. The target topic was 'rational prescribing of antibiotics'. Some 18,766 randomly selected outpatient drug prescriptions were studied. Antibiotics (and sulphonamides) were prescribed to 33.2% of the patients. An overall trend towards a decrease in proportion of patients prescribed antibiotics in the two intervention groups was seen, although the difference was not significant (p greater than 0.05) compared to the control group. This is similar to the effect of written information on prescribing in other studies. A mean difference of -7.4% in written, -7.3% in written + seminar and -0.4% in the control group was shown. The general antibiotic prescribing pattern did not change in any of the three groups. Penicillin was the most commonly prescribed antibiotic and tetracycline was only rarely prescribed to children. This experiment indicates the feasibility of drug information intervention studies in developing countries.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Examining clinical supervision as a mechanism for changes in practice: a research protocol.

    PubMed

    Dilworth, Sophie; Higgins, Isabel; Parker, Vicki; Kelly, Brian; Turner, Jane

    2014-02-01

    This paper describes the research protocol for a study exploring if and how clinical supervision facilitates change in practice relating to psychosocial aspects of care for Health Professionals, who have been trained to deliver a psychosocial intervention to adults with cancer. There is a recognized need to implement care that is in line with clinical practice guidelines for the psychosocial care of adults with cancer. Clinical supervision is recommended as a means to support Health Professionals in providing the recommended psychosocial care. A qualitative design embedded within an experimental, stepped wedge randomized control trial. The study will use discourse analysis to analyse audio-recorded data collected in clinical supervision sessions that are being delivered as one element of a large randomized control trial. The sessions will be attended primarily by nurses, but including physiotherapists, radiation therapists, occupational therapists. The Health Professionals are participants in a randomized control trial designed to reduce anxiety and depression of distressed adults with cancer. The sessions will be facilitated by psychiatrists experienced in psycho-oncology and the provision of clinical supervision. The proposed research is designed specifically to facilitate exploration of the mechanisms by which clinical supervision enables Health Professionals to deliver a brief, tailored psychosocial intervention in the context of their everyday practice. This is the first study to use discourse analysis embedded within an experimental randomized control trial to explore the mechanisms of change generated within clinical supervision by analysing the discourse within the clinical supervision sessions. © 2013 John Wiley & Sons Ltd.

  9. Irrigation of Abdomen With Imipenem Solution Decreases Surgical Site Infections in Patients With Perforated Appendicitis: A Randomized Clinical Trial

    PubMed Central

    Hesami, Mohammad Ali; Alipour, Hamid; Nikoupour Daylami, Hamed; Alipour, Bijan; Bazargan-Hejazi, Shahrzad; Ahmadi, Alireza

    2014-01-01

    Background: Perforated appendicitis is one of the most common causes of acute abdomen requiring emergent surgery for immediate appendectomy and peritoneal cavity irrigation; however, the efficacy of irrigation with antibiotic solutions is controversial. Objectives: The aim of this study was to assess the efficacy of imipenem solution irrigation on post-operative surgical site infections (SSIs), hospital length of stay, and hospital costs. We hypothesized that there would be lower rate of SSIs, a shorter hospital stay, and lower hospital cost in patients with perforated appendicitis who received peritoneal cavity irrigation with imipenem solution in comparison to their counterparts who received irrigation with normal saline. Patients and Methods: In this randomized single-blind parallel-group clinical trial, we enrolled 90 patients with perforated appendicitis with 12-50 years of age and randomly allocated them into experimental group (n = 45) and control group (n = 45). The control group received peritoneal irrigation with normal saline (0.9%) and experimental group underwent peritoneal irrigation with imipenem solution (1 mg/mL). All surgical procedures were performed in Imam Reza Hospital of Kermanshah University of Medical Sciences. The study primary outcome was surgical site infections (including wound infection and abdominal abscess) and the secondary outcomes were length of hospital stay and hospital cost. Chi-squared and t-tests were used to analyze the study data. Results: Imipenem solution irrigation was associated with significant clinical improvement at one-month follow-up. The experimental group presented with significantly lower rate of SSIs and shorter length of hospital stay. The experimental group had lower rate of SSIs compared to the control group (4.4% vs. 22.2%, respectively) (p= 0.013). The duration of hospital stay was nearly one day longer in control group (5.84 ± 2.58 days) vs. experimental group (4.91 ± 1.29 days) (P = 0.034), and hospital costs were $50 lower in experimental group ($500 ± $292) vs. control group ($450 ± $170) (P = 0.281). Conclusions: The study findings revealed that peritoneal lavage with imipenem solution (1 mg/mL) decreases the rate of post-operative SSIs in patients with perforated appendicitis in comparison to patients irrigated with normal saline alone. These patients also had shorter hospital stay, and lower hospital costs. PMID:24910794

  10. Supporting stress management for women undergoing the early stages of fertility treatment: a cluster-randomized controlled trial.

    PubMed

    Mori, Akiko

    2009-06-01

    The purpose of this study was to determine the effects of a support program for the stress management of women undergoing fertility treatment to reduce stress related to infertility and treatment. We randomly assigned seven institutions into an experimental group (four institutions, n = 96) and a control group (three institutions, n = 44) using cluster randomization. The women in the experimental group were asked to continue stress management homework for 3 months. A nurse provided feedback on the homework every month. Those in the control group were given only the booklet. The primary outcomes were the risk ratios of "depression" and "anxiety" according to the Hospital Anxiety and Depression Scale. The secondary outcomes were "health status" from the Medical Outcomes Study Short-Form 36-item Health Survey (SF-36) v2 and "satisfaction" from the Visual Analogue Scale. We excluded 15 women who became pregnant and performed an intention-to-treat analysis of 125 women. There were no differences in the incidence of depression and anxiety between the experimental and control groups. There were significant interaction effects between the program and time in the scores of the two subscales of SF-36 and the summary. There was no difference in satisfaction. The use of ovulation-enhancing agents showed that the scores of "role functioning physical" and "physical component summary" in the non-use subgroup were higher at 2 and 3 months in the experimental group, compared to the control group. Positive effects of the support program were observed on two subscales of the SF-36 in the subgroup that did not use ovulation-enhancing agents.

  11. On the Choice of Adequate Randomization Ranges for Limiting the Use of Unwanted Cues in Same-Different, Dual-Pair, and Oddity Tasks

    PubMed Central

    Dai, Huanping; Micheyl, Christophe

    2010-01-01

    A major concern when designing a psychophysical experiment is that participants may use another stimulus feature (“cue”) than that intended by the experimenter. One way to avoid this involves applying random variations to the corresponding feature across stimulus presentations, to make the “unwanted” cue unreliable. An important question facing experimenters who use this randomization (“roving”) technique is: How large should the randomization range be to ensure that participants cannot achieve a certain proportion correct (PC) by using the unwanted cue, while at the same time avoiding unnecessary interference of the randomization with task performance? Previous publications have provided formulas for the selection of adequate randomization ranges in yes-no and multiple-alternative, forced-choice tasks. In this article, we provide figures and tables, which can be used to select randomization ranges that are better suited to experiments involving a same-different, dual-pair, or oddity task. PMID:20139466

  12. Distinguishability of generic quantum states

    NASA Astrophysics Data System (ADS)

    Puchała, Zbigniew; Pawela, Łukasz; Życzkowski, Karol

    2016-06-01

    Properties of random mixed states of dimension N distributed uniformly with respect to the Hilbert-Schmidt measure are investigated. We show that for large N , due to the concentration of measure, the trace distance between two random states tends to a fixed number D ˜=1 /4 +1 /π , which yields the Helstrom bound on their distinguishability. To arrive at this result, we apply free random calculus and derive the symmetrized Marchenko-Pastur distribution, which is shown to describe numerical data for the model of coupled quantum kicked tops. Asymptotic value for the root fidelity between two random states, √{F }=3/4 , can serve as a universal reference value for further theoretical and experimental studies. Analogous results for quantum relative entropy and Chernoff quantity provide other bounds on the distinguishablity of both states in a multiple measurement setup due to the quantum Sanov theorem. We study also mean entropy of coherence of random pure and mixed states and entanglement of a generic mixed state of a bipartite system.

  13. Involving Parents in Paired Reading with Preschoolers: Results from a Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Lam, Shui-fong; Chow-Yeung, Kamfung; Wong, Bernard P. H.; Lau, Kwok Kiu; Tse, Shuk In

    2013-01-01

    A paired reading program was implemented for 195 Hong Kong preschoolers (mean age = 4.7 years) and their parents from families with a wide range of family income. The preschoolers were randomly assigned to experimental or waitlist control groups. The parents in the experimental group received 12 sessions of school-based training on paired reading…

  14. Delayed School Start Times and Adolescent Sleep: A Systematic Review of the Experimental Evidence

    PubMed Central

    Minges, Karl E.; Redeker, Nancy S.

    2016-01-01

    Summary Many schools have instituted later morning start times to improve sleep, academic, and other outcomes in response to the mismatch between youth circadian rhythms and early morning start times. However, there has been no systematic synthesis of the evidence on the effects of this practice. To examine the impact of delayed school start time on students’ sleep, health, and academic outcomes, electronic databases were systematically searched and data were extracted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Six studies satisfied selection criteria and used pre-post, no control (n=3), randomized controlled trial (n=2), and quasi-experimental (n=1) designs. School start times were delayed 25 to 60 minutes, and correspondingly, total sleep time increased from 25 to 77 minutes per weeknight. Some studies revealed reduced daytime sleepiness, depression, caffeine use, tardiness to class, and trouble staying awake. Overall, the evidence supports recent non-experimental study findings and calls for policy that advocates for delayed school start time to improve sleep. This presents a potential long-term solution to chronic sleep restriction during adolescence. However, there is a need for rigorous randomized study designs and reporting of consistent outcomes, including objective sleep measures and consistent measures of health and academic performance. PMID:26545246

  15. HandTutor™ enhanced hand rehabilitation after stroke--a pilot study.

    PubMed

    Carmeli, Eli; Peleg, Sara; Bartur, Gadi; Elbo, Enbal; Vatine, Jean-Jacques

    2011-12-01

    This study assessed the potential therapeutic benefi t of using HandTutor™ in combination with traditional rehabilitation in a post-stroke sub-acute population. The study compares an experimental group receiving traditional therapy combined with HandTutorTM treatment, against a control group receiving only traditional therapy. An assessor-blinded, randomized controlled pilot trial, was conducted in the Reuth rehabilitation unit in Israel. Thirty-one stroke patients in the sub-acute phase, were randomly assigned to one of the two groups (experimental or control) in sets of three. The experimental group (n = 16) underwent a hand rehabilitation programme using the HandTutorTM combined with traditional therapy. The control group (n = 15) received only traditional therapy. The treatment schedules for both groups were of similar duration and frequency. Improvements were evaluated using three indicators: 1) The Brunnström-Fugl-Meyer (FM) test, 2) the Box and Blocks (B&B) test and 3) improvement parameters as determined by the HandTutorTM software. Following 15 consecutive treatment sessions, a signifi cant improvement was observed within the experimental group (95% confi dence intervals) compared with the control group: B&B p = 0.015; FM p = 0.041, HandTutor™ performance accuracy on x axis and performance accuracy on y axis p < 0.0003. The results from this pilot study support further investigation of the use of the HandTutorTM in combination with traditional occupational therapy and physiotherapy during post stroke hand function rehabilitation.

  16. A perfect correlate does not a surrogate make

    PubMed Central

    Baker, Stuart G; Kramer, Barnett S

    2003-01-01

    Background There is common belief among some medical researchers that if a potential surrogate endpoint is highly correlated with a true endpoint, then a positive (or negative) difference in potential surrogate endpoints between randomization groups would imply a positive (or negative) difference in unobserved true endpoints between randomization groups. We investigate this belief when the potential surrogate and unobserved true endpoints are perfectly correlated within each randomization group. Methods We use a graphical approach. The vertical axis is the unobserved true endpoint and the horizontal axis is the potential surrogate endpoint. Perfect correlation within each randomization group implies that, for each randomization group, potential surrogate and true endpoints are related by a straight line. In this scenario the investigator does not know the slopes or intercepts. We consider a plausible example where the slope of the line is higher for the experimental group than for the control group. Results In our example with unknown lines, a decrease in mean potential surrogate endpoints from control to experimental groups corresponds to an increase in mean true endpoint from control to experimental groups. Thus the potential surrogate endpoints give the wrong inference. Similar results hold for binary potential surrogate and true outcomes (although the notion of correlation does not apply). The potential surrogate endpointwould give the correct inference if either (i) the unknown lines for the two group coincided, which means that the distribution of true endpoint conditional on potential surrogate endpoint does not depend on treatment group, which is called the Prentice Criterion or (ii) if one could accurately predict the lines based on data from prior studies. Conclusion Perfect correlation between potential surrogate and unobserved true outcomes within randomized groups does not guarantee correct inference based on a potential surrogate endpoint. Even in early phase trials, investigators should not base conclusions on potential surrogate endpoints in which the only validation is high correlation with the true endpoint within a group. PMID:12962545

  17. Voucher-Based Contingent Reinforcement of Smoking Abstinence among Methadone-Maintained Patients: A Pilot Study

    ERIC Educational Resources Information Center

    Dunn, Kelly E.; Sigmon, Stacey C.; Thomas, Colleen S.; Heil, Sarah H.; Higgins, Stephen T.

    2008-01-01

    This study evaluated the efficacy of a contingency management (CM) intervention to promote smoking cessation in methadone-maintained patients. Twenty participants, randomized into contingent (n = 10) or noncontingent (n = 10) experimental conditions, completed the 14-day study. Abstinence was determined using breath carbon monoxide and urine…

  18. Studying the Effectiveness of an Online Language Learning Platform in China

    ERIC Educational Resources Information Center

    Baker, Ryan; Wang, Feng; Ma, Zhenjun; Ma, Wei; Zheng, Shiyue

    2018-01-01

    In this paper we evaluate the effectiveness of an adaptive online learning platform, designed to support Chinese students in learning the English language. The adaptive platform is studied in three studies, where the experimental platform is compared to an alternate, non-adaptive platform, with random assignment to conditions (the adaptive…

  19. Hydrotherapy for the treatment of pain in people with multiple sclerosis: a randomized controlled trial.

    PubMed

    Castro-Sánchez, Adelaida María; Matarán-Peñarrocha, Guillermo A; Lara-Palomo, Inmaculada; Saavedra-Hernández, Manuel; Arroyo-Morales, Manuel; Moreno-Lorenzo, Carmen

    2012-01-01

    Background. Multiple sclerosis (MS) is a chronic demyelinating neurological disease. Several studies have reported that complementary and alternative therapies can have positive effects against pain in these patients. Objective. The objective was to investigate the effectiveness of an Ai-Chi aquatic exercise program against pain and other symptoms in MS patients. Methods. In this randomized controlled trial, 73 MS patients were randomly assigned to an experimental or control group for a 20-week treatment program. The experimental group underwent 40 sessions of Ai-Chi exercise in swimming pool and the control group 40 sessions of abdominal breathing and contraction-relaxation exercises in therapy room. Outcome variables were pain, disability, spasm, depression, fatigue, and autonomy, which were assessed before the intervention and immediately and at 4 and 10 weeks after the last treatment session. Results. The experimental group showed a significant (P < 0.028) and clinically relevant decrease in pain intensity versus baseline, with an immediate posttreatment reduction in median visual analogue scale scores of 50% that was maintained for up to 10 weeks. Significant improvements were also observed in spasm, fatigue, disability, and autonomy. Conclusion. According to these findings, an Ai-Chi aquatic exercise program improves pain, spasms, disability, fatigue, depression, and autonomy in MS patients.

  20. Hydrotherapy for the Treatment of Pain in People with Multiple Sclerosis: A Randomized Controlled Trial

    PubMed Central

    Castro-Sánchez, Adelaida María; Matarán-Peñarrocha, Guillermo A.; Lara-Palomo, Inmaculada; Saavedra-Hernández, Manuel; Arroyo-Morales, Manuel; Moreno-Lorenzo, Carmen

    2012-01-01

    Background. Multiple sclerosis (MS) is a chronic demyelinating neurological disease. Several studies have reported that complementary and alternative therapies can have positive effects against pain in these patients. Objective. The objective was to investigate the effectiveness of an Ai-Chi aquatic exercise program against pain and other symptoms in MS patients. Methods. In this randomized controlled trial, 73 MS patients were randomly assigned to an experimental or control group for a 20-week treatment program. The experimental group underwent 40 sessions of Ai-Chi exercise in swimming pool and the control group 40 sessions of abdominal breathing and contraction-relaxation exercises in therapy room. Outcome variables were pain, disability, spasm, depression, fatigue, and autonomy, which were assessed before the intervention and immediately and at 4 and 10 weeks after the last treatment session. Results. The experimental group showed a significant (P < 0.028) and clinically relevant decrease in pain intensity versus baseline, with an immediate posttreatment reduction in median visual analogue scale scores of 50% that was maintained for up to 10 weeks. Significant improvements were also observed in spasm, fatigue, disability, and autonomy. Conclusion. According to these findings, an Ai-Chi aquatic exercise program improves pain, spasms, disability, fatigue, depression, and autonomy in MS patients. PMID:21785645

  1. Optical nano artifact metrics using silicon random nanostructures

    NASA Astrophysics Data System (ADS)

    Matsumoto, Tsutomu; Yoshida, Naoki; Nishio, Shumpei; Hoga, Morihisa; Ohyagi, Yasuyuki; Tate, Naoya; Naruse, Makoto

    2016-08-01

    Nano-artifact metrics exploit unique physical attributes of nanostructured matter for authentication and clone resistance, which is vitally important in the age of Internet-of-Things where securing identities is critical. However, expensive and huge experimental apparatuses, such as scanning electron microscopy, have been required in the former studies. Herein, we demonstrate an optical approach to characterise the nanoscale-precision signatures of silicon random structures towards realising low-cost and high-value information security technology. Unique and versatile silicon nanostructures are generated via resist collapse phenomena, which contains dimensions that are well below the diffraction limit of light. We exploit the nanoscale precision ability of confocal laser microscopy in the height dimension; our experimental results demonstrate that the vertical precision of measurement is essential in satisfying the performances required for artifact metrics. Furthermore, by using state-of-the-art nanostructuring technology, we experimentally fabricate clones from the genuine devices. We demonstrate that the statistical properties of the genuine and clone devices are successfully exploited, showing that the liveness-detection-type approach, which is widely deployed in biometrics, is valid in artificially-constructed solid-state nanostructures. These findings pave the way for reasonable and yet sufficiently secure novel principles for information security based on silicon random nanostructures and optical technologies.

  2. Effect of therapeutic exercises on pregnancy-related low back pain and pelvic girdle pain: Secondary analysis of a randomized controlled trial.

    PubMed

    Sklempe Kokic, Iva; Ivanisevic, Marina; Uremovic, Melita; Kokic, Tomislav; Pisot, Rado; Simunic, Bostjan

    2017-03-06

    To investigate the effect of a supervised, structured exercise programme on the occurrence and severity of pregnancy-related lumbopelvic pain. Randomized controlled trial. A total of 45 pregnant women were randomly assigned to 2 groups: an experimental group (n = 20; mean age 32.8 (standard deviation (SD) 3.6) years) and a control group (n = 22; mean age 32.2 years (SD 4.9)). Exercise intervention for the experimental group consisted of aerobic and resistance exercises performed bi-weekly from the date of inclusion into the study until the end of pregnancy, together with at least 30 min of brisk daily walks. A numeric rating scale, Roland-Morris Disability Questionnaire (RMDQ), and Pelvic Girdle Questionnaire (PGQ) were used to measure outcomes. The control group received only standard antenatal care. There were significant differences between the 2 groups on the numeric rating scale, PGQ and RMDQ scores in the 36th week of pregnancy (p = 0.017; p = 0.005; p < 0.001, respectively) in favour of the experimental group. The exercise programme had a beneficial effect on the severity of lumbopelvic pain in pregnancy, reducing the intensity of pain and the level of disability experienced as a result.

  3. Parametric Analytical Studies for the Nonlinear Dynamic Response of the Tile/Pad Space Shuttle Thermal Protection System

    NASA Technical Reports Server (NTRS)

    Edighoffer, H.

    1981-01-01

    The studies examined for imposed sinusoidal and random motions of the shuttle skin and/or applied tile pressure. Studies are performed using the computer code DYNOTA which takes into account the highly nonlinear stiffening hysteresis and viscous behavior of the pad joining the tile to the shuttle skin. Where available, experimental data are used to confirm the validity of the analysis. Both analytical and experimental studies reveal that the system resonant frequency is very high for low amplitude oscillations but decreases rapidly to a minimum value with increasing amplitude.

  4. Randomness increases self-reported anxiety and neurophysiological correlates of performance monitoring

    PubMed Central

    Kay, Aaron C.; Inzlicht, Michael

    2015-01-01

    Several prominent theories spanning clinical, social and developmental psychology suggest that people are motivated to see the world as a sensible orderly place. These theories presuppose that randomness is aversive because it is associated with unpredictability. If this is the case, thinking that the world is random should lead to increased anxiety and heightened monitoring of one’s actions and their consequences. Here, we conduct experimental tests of both of these ideas. Participants read one of three passages: (i) comprehensible order, (ii) incomprehensible order and (iii) randomness. In Study 1, we examined the effects of these passages on self-reported anxiety. In Study 2, we examined the effects of the same manipulation on the error-related negativity (ERN), an event-related brain potential associated with performance monitoring. We found that messages about randomness increased self-reported anxiety and ERN amplitude relative to comprehensible order, whereas incomprehensible order had intermediate effects. These results lend support to the theoretically important idea that randomness is unsettling because it implies that the world is unpredictable. PMID:25062840

  5. Efficacy of antimicrobial photodynamic therapy in the disinfection of acrylic denture surfaces: A systematic review.

    PubMed

    Varela Kellesarian, Sergio; Abduljabbar, Tariq; Vohra, Fahim; Malmstrom, Hans; Yunker, Michael; Varela Kellesarian, Tammy; Romanos, Georgios E; Javed, Fawad

    2017-03-01

    The aim of the present systematic review was to assess the efficacy of antimicrobial photodynamic therapy (aPDT) in the disinfection of acrylic denture surfaces. IN order to address the focused question: "Is aPDT more effective in decontaminating denture surfaces compared with traditional denture-disinfection techniques?" an electronic search without time or language restrictions was conducted up to November 2016 in indexed databases using different key words. The exclusion criteria included qualitative and/or quantitative reviews, case reports, case series, commentaries, letters to the editor, interviews, and updates. A total of 14 studies were included and processed for data extraction, out of which 1 study was a randomized clinical trial and 13 studies were performed in vitro. Results from 12 experimental studies reported that aPDT was effective in reducing bacteria and/or yeast cultured in single or multispecies biofilm growth on acrylic resin specimens. One experimental study reported selective microorganism reduction on acrylic resin after aPDT. One clinical randomized control trial reported that aPDT presented similar microorganism reduction compared with oral antifungal medication for the disinfection of denture surfaces. The role of aPDT in the disinfection of acrylic resin surfaces is unclear. From a clinical perspective further randomized control trials are needed to assess the efficacy of aPDT in the disinfection of acrylic resin surfaces. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. The Effects of Experimentally Manipulated Social Status on Acute Eating Behavior: A Randomized, Crossover Pilot Study

    PubMed Central

    Cardel, MI; Johnson, SL; Beck, J; Dhurandhar, E; Keita, AD; Tomczik, AC; Pavela, G; Huo, T; Janicke, DM; Muller, K; Piff, PK; Peters, JC; Hill, JO; Allison, DB

    2016-01-01

    Both subjective and objectively measured social status has been associated with multiple health outcomes, including weight status, but the mechanism for this relationship remains unclear. Experimental studies may help identify the causal mechanisms underlying low social standing as a pathway for obesity. Our objective was to investigate the effects of experimentally manipulated social status on ad libitum acute dietary intakes and stress-related outcomes as potential mechanisms relating social status and weight. This was a pilot feasibility, randomized, crossover study in Hispanic young adults (n=9; age 19–25; 67% female; BMI ≥18.5 and ≤30 kg/m2). At visit 1, participants consumed a standardized breakfast and were randomized to a high social status position (HIGH) or low social status position (LOW) in a rigged game of Monopoly™. The rules for the game differed substantially in terms of degree of ‘privilege’ depending on randomization to HIGH or LOW. Following Monopoly™, participants were given an ad libitum buffet meal and energy intakes (kcal) were estimated by pre- and post-weighing foods consumed. Stress-related markers were measured at baseline, after the game of Monopoly™, and after lunch. Visit 2 used the same standardized protocol; however, participants were exposed to the opposite social status condition. When compared to HIGH, participants in LOW consumed 130 more calories (p=0.07) and a significantly higher proportion of their daily calorie needs in the ad libitum buffet meal (39% in LOW versus 31% in HIGH; p=0.04). In LOW, participants reported decreased feelings of pride and powerfulness following Monopoly™ (p=0.05) and after their lunch meal (p=0.08). Relative to HIGH, participants in LOW demonstrated higher heart rates following Monopoly™ (p=0.06), but this relationship was not significant once lunch was consumed (p=0.31). Our pilot data suggest a possible causal relationship between experimentally manipulated low social status and increased acute energy intakes in Hispanic young adults, potentially influenced by decreased feelings of pride and powerfulness. Increased energy intake over time, resulting in positive energy balance, could contribute to increased risk for obesity, which could partially explain the observed relationship between low social standing and higher weight. Larger and longitudinal studies in a diverse sample need to be conducted to confirm findings, increase generalizability, and assess whether this relationship persists over time. PMID:27094920

  7. The effects of experimentally manipulated social status on acute eating behavior: A randomized, crossover pilot study.

    PubMed

    Cardel, M I; Johnson, S L; Beck, J; Dhurandhar, E; Keita, A D; Tomczik, A C; Pavela, G; Huo, T; Janicke, D M; Muller, K; Piff, P K; Peters, J C; Hill, J O; Allison, D B

    2016-08-01

    Both subjective and objectively measured social status has been associated with multiple health outcomes, including weight status, but the mechanism for this relationship remains unclear. Experimental studies may help identify the causal mechanisms underlying low social standing as a pathway for obesity. Our objective was to investigate the effects of experimentally manipulated social status on ad libitum acute dietary intakes and stress-related outcomes as potential mechanisms relating social status and weight. This was a pilot feasibility, randomized, crossover study in Hispanic young adults (n=9; age 19-25; 67% female; BMI ≥18.5 and ≤30kg/m(2)). At visit 1, participants consumed a standardized breakfast and were randomized to a high social status position (HIGH) or low social status position (LOW) in a rigged game of Monopoly™. The rules for the game differed substantially in terms of degree of 'privilege' depending on randomization to HIGH or LOW. Following Monopoly™, participants were given an ad libitum buffet meal and energy intakes (kcal) were estimated by pre- and post-weighing foods consumed. Stress-related markers were measured at baseline, after the game of Monopoly™, and after lunch. Visit 2 used the same standardized protocol; however, participants were exposed to the opposite social status condition. When compared to HIGH, participants in LOW consumed 130 more calories (p=0.07) and a significantly higher proportion of their daily calorie needs in the ad libitum buffet meal (39% in LOW versus 31% in HIGH; p=0.04). In LOW, participants reported decreased feelings of pride and powerfulness following Monopoly™ (p=0.05) and after their lunch meal (p=0.08). Relative to HIGH, participants in LOW demonstrated higher heart rates following Monopoly™ (p=0.06), but this relationship was not significant once lunch was consumed (p=0.31). Our pilot data suggest a possible causal relationship between experimentally manipulated low social status and increased acute energy intakes in Hispanic young adults, potentially influenced by decreased feelings of pride and powerfulness. Increased energy intake over time, resulting in positive energy balance, could contribute to increased risk for obesity, which could partially explain the observed relationship between low social standing and higher weight. Larger and longitudinal studies in a diverse sample need to be conducted to confirm findings, increase generalizability, and assess whether this relationship persists over time. Published by Elsevier Inc.

  8. Effect of continuous oral suctioning on the development of ventilator-associated pneumonia: a pilot randomized controlled trial.

    PubMed

    Chow, Meyrick C M; Kwok, Shu-Man; Luk, Hing-Wah; Law, Jenny W H; Leung, Bartholomew P K

    2012-11-01

    Both continuous and intermittent aspiration of subglottic secretions by means of specially designed endotracheal tubes containing a separate dorsal lumen that opens into the subglottic region have been shown to be useful in reducing ventilator-associated pneumonia (VAP). However, the high cost of these tubes restricts their use. The aim of this pilot randomized controlled trial was to test the effect of a low-cost device (saliva ejector) for continuous oral suctioning (COS) on the incidence of VAP in patients receiving mechanical ventilation. The study was conducted in the six-bed medical-surgical ICU of a hospital with over 400 beds that provides comprehensive medical services to the public. The design of this study was a parallel-group randomized controlled trial. While both the experimental and control groups used the conventional endotracheal tube, the saliva ejector was only applied to patients assigned to the experimental group. The device was put between the patient's cheek and teeth, and then connected to 100mmHg of suction for the continuous drainage of saliva. Fourteen patients were randomized to receive COS and 13 patients were randomized to the control group. The two groups were similar in demographics, reasons for intubation, co-morbidity, and risk factors for acquiring VAP. VAP was found in 3 patients (23.1%; 71 episodes of VAP per 1000 ventilation days) receiving COS and in 10 patients (83.3%; 141 episodes of VAP per 1000 ventilation days) in the control group (relative risk, 0.28; 95% confidence interval, 0.10-0.77; p=0.003). The duration of mechanical ventilation in the experimental group was 3.2 days (SD 1.3), while that in the control group was 5.9 days (SD 2.8) (p=0.009); and the length of ICU stay was 4.8 days (SD 1.6) versus 9.8 days (SD 6.3) for the experimental and control groups, respectively (p=0.019). Continuous clearance of oral secretion by the saliva ejector may have an important role to play in reducing the rate of VAP, decreasing the duration of mechanical ventilation, and shortening the length of stay of patients in the ICU. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Assessment on Experimental Bacterial Biofilms and in Clinical Practice of the Efficacy of Sampling Solutions for Microbiological Testing of Endoscopes

    PubMed Central

    Aumeran, C.; Thibert, E.; Chapelle, F. A.; Hennequin, C.; Lesens, O.

    2012-01-01

    Opinions differ on the value of microbiological testing of endoscopes, which varies according to the technique used. We compared the efficacy on bacterial biofilms of sampling solutions used for the surveillance of the contamination of endoscope channels. To compare efficacy, we used an experimental model of a 48-h Pseudomonas biofilm grown on endoscope internal tubing. Sampling of this experimental biofilm was performed with a Tween 80-lecithin-based solution, saline, and sterile water. We also performed a randomized prospective study during routine clinical practice in our hospital sampling randomly with two different solutions the endoscopes after reprocessing. Biofilm recovery expressed as a logarithmic ratio of bacteria recovered on bacteria initially present in biofilm was significantly more effective with the Tween 80-lecithin-based solution than with saline solution (P = 0.002) and sterile water (P = 0.002). There was no significant difference between saline and sterile water. In the randomized clinical study, the rates of endoscopes that were contaminated with the Tween 80-lecithin-based sampling solution and the saline were 8/25 and 1/25, respectively (P = 0.02), and the mean numbers of bacteria recovered were 281 and 19 CFU/100 ml (P = 0.001), respectively. In conclusion, the efficiency and therefore the value of the monitoring of endoscope reprocessing by microbiological cultures is dependent on the sampling solutions used. A sampling solution with a tensioactive action is more efficient than saline in detecting biofilm contamination of endoscopes. PMID:22170930

  10. The Effect of Music on Anxiety and Cardiovascular Indices in Patients Undergoing Coronary Artery Bypass Graft: A Randomized Controlled Trial.

    PubMed

    Heidari, Saeide; Babaii, Atye; Abbasinia, Mohammad; Shamali, Mahdi; Abbasi, Mohammad; Rezaei, Mahboobe

    2015-12-01

    The instability of cardiovascular indices and anxiety disorders are common among patients undergoing coronary artery bypass graft (CABG) and could interfere with their recovery. Therefore, improving the cardiovascular indices and anxiety is essential. This study aimed to investigate the effect of music therapy on anxiety and cardiovascular indices in patients undergoing CABG. In this randomized controlled trial, 60 patients hospitalized in the cardiovascular surgical intensive care unit of Shahid Beheshti Hospital in Qom city, Iran, in 2013 were selected using a consecutive sampling method and randomly allocated into the experimental and control groups. In the experimental group, patients received 30 minutes of light music, whereas in the control group, patients had 30 minutes of rest in bed. The cardiovascular indices and anxiety were measured immediately before, immediately after and half an hour after the study. Data were analyzed using the chi-square test and repeated measures analysis of variance. Compared to the immediately before intervention, the mean anxiety scores immediately after and 30 minutes after the intervention were significantly lower in the experimental group (P < 0.037) while it did not significantly change in the control group. However, there were no significant differences regarding the cardiovascular indices in the three consecutive measurements (P > 0.05). Music therapy is effective in decreasing anxiety among patients undergoing CABG. However, the intervention was not effective on cardiovascular indices. Music can effectively be used as a non-pharmacological method to manage anxiety after CABG.

  11. Experimental knee joint pain during strength training and muscle strength gain in healthy subjects: a randomized controlled trial.

    PubMed

    Sørensen, T J; Langberg, H; Hodges, P W; Bliddal, H; Henriksen, M

    2012-01-01

    Knee joint pain and reduced quadriceps strength are cardinal symptoms in many knee pathologies. In people with painful knee pathologies, quadriceps exercise reduces pain, improves physical function, and increases muscle strength. A general assumption is that pain compromises muscle function and thus may prevent effective rehabilitation. This study evaluated the effects of experimental knee joint pain during quadriceps strength training on muscle strength gain in healthy individuals. Twenty-seven healthy untrained volunteers participated in a randomized controlled trial of quadriceps strengthening (3 times per week for 8 weeks). Participants were randomized to perform resistance training either during pain induced by injections of painful hypertonic saline (pain group, n = 13) or during a nonpainful control condition with injection of isotonic saline (control group, n = 14) into the infrapatellar fat pad. The primary outcome measure was change in maximal isokinetic muscle strength in knee extension/flexion (60, 120, and 180 degrees/second). The group who exercised with pain had a significantly larger improvement in isokinetic muscle strength at all angular velocities of knee extension compared to the control group. In knee flexion there were improvements in isokinetic muscle strength in both groups with no between-group differences. Experimental knee joint pain improved the training-induced gain in muscle strength following 8 weeks of quadriceps training. It remains to be studied whether knee joint pain has a positive effect on strength gain in patients with knee pathology. Copyright © 2012 by the American College of Rheumatology.

  12. Combined effects of sensory cueing and limb activation on unilateral neglect in subacute left hemiplegic stroke patients: a randomized controlled pilot study.

    PubMed

    Fong, Kenneth N K; Yang, Nicole Y H; Chan, Marko K L; Chan, Dora Y L; Lau, Andy F C; Chan, Dick Y W; Cheung, Joyce T Y; Cheung, Hobby K Y; Chung, Raymond C K; Chan, Chetwyn C H

    2013-07-01

    To compare the effects of contralesional sensory cueing and limb activation with that of sham control in the treatment of unilateral neglect after stroke. A randomized, single-blinded, sham-controlled pilot study. Two rehabilitation hospitals. Forty subacute left hemiplegic stroke inpatients with unilateral neglect. Participants were assigned randomly to 1 of 2 groups. The experimental group wore a wristwatch cueing device over the hemiplegic arm for three hours a day, five days per week, for three weeks, and also underwent conventional rehabilitation. Patients were encouraged to move their hemiplegic arm five consecutive times after each prompt. The sham group underwent the same rehabilitation process, except they wore a sham device. Neglect, arm motor performance, and overall functioning were assessed pre- and posttraining, and at follow-up. There were no significant differences between groups in outcome measures except the neglect drawing tasks (p = 0.034) (the mean gain score from baseline to follow-up assessment was 5.2 (3.7) in the experimental group and 1.9 (3.5) in the sham group), across three time intervals. The experimental group showed greater improvement in arm motor performance than did the sham group. The results did not confirm that sensory cueing and limb activation treatment is effective when compared with those receiving placebo to reduce unilateral neglect, but it might be useful for promoting hemiplegic arm performance in stroke patients.

  13. Use of virtual reality intervention to improve reaction time in children with cerebral palsy: A randomized controlled trial.

    PubMed

    Pourazar, Morteza; Mirakhori, Fatemeh; Hemayattalab, Rasool; Bagherzadeh, Fazlolah

    2017-09-21

    The purpose of this study was to investigate the training effects of Virtual Reality (VR) intervention program on reaction time in children with cerebral palsy. Thirty boys ranging from 7 to 12 years (mean = 11.20; SD = .76) were selected by available sampling method and randomly divided into the experimental and control groups. Simple Reaction Time (SRT) and Discriminative Reaction Time (DRT) were measured at baseline and 1 day after completion of VR intervention. Multivariate analysis of variance (MANOVA) and paired sample t-test were performed to analyze the results. MANOVA test revealed significant effects for group in posttest phase, with lower reaction time in both measures for the experimental group. Based on paired sample t-test results, both RT measures significantly improved in experimental group following the VR intervention program. This paper proposes VR as a promising tool into the rehabilitation process for improving reaction time in children with cerebral palsy.

  14. The effect of the support program on the resilience of female family caregivers of stroke patients: Randomized controlled trial.

    PubMed

    İnci, Fadime Hatice; Temel, Ayla Bayik

    2016-11-01

    The purpose of the study was to determine the effect of a support program on the resilience of female family caregivers of stroke patients. This is a randomized controlled trial. The sample consisted 70 female family caregivers (34 experimental, 36 control group). Data were collected three times (pretest-posttest, follow-up test). Data were collected using the demographical data form, the Family Index of Regenerativity and Adaptation-General. A significant difference was determined between the experimental and control group's follow-up test scores for relative and friend support, social support and family-coping coherence. A significant difference was determined between the experimental group's mean pretest, posttest and follow-up test scores in terms of family strain, relative and friend support, social support, family coping-coherence, family hardiness and family distress. These results suggest that the Support Program contributes to the improvement of the components of resilience of family caregivers of stroke patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Machine learning algorithms for the creation of clinical healthcare enterprise systems

    NASA Astrophysics Data System (ADS)

    Mandal, Indrajit

    2017-10-01

    Clinical recommender systems are increasingly becoming popular for improving modern healthcare systems. Enterprise systems are persuasively used for creating effective nurse care plans to provide nurse training, clinical recommendations and clinical quality control. A novel design of a reliable clinical recommender system based on multiple classifier system (MCS) is implemented. A hybrid machine learning (ML) ensemble based on random subspace method and random forest is presented. The performance accuracy and robustness of proposed enterprise architecture are quantitatively estimated to be above 99% and 97%, respectively (above 95% confidence interval). The study then extends to experimental analysis of the clinical recommender system with respect to the noisy data environment. The ranking of items in nurse care plan is demonstrated using machine learning algorithms (MLAs) to overcome the drawback of the traditional association rule method. The promising experimental results are compared against the sate-of-the-art approaches to highlight the advancement in recommendation technology. The proposed recommender system is experimentally validated using five benchmark clinical data to reinforce the research findings.

  16. A virtual patient educational activity to improve interprofessional competencies: A randomized trial.

    PubMed

    Shoemaker, Michael J; de Voest, Margaret; Booth, Andrew; Meny, Lisa; Victor, Justin

    2015-01-01

    The purpose of the present study was to determine whether an interprofessional virtual patient educational activity improved interprofessional competencies in pharmacy, physician assistant, and physical therapy graduate students. Seventy-two fifth semester pharmacy (n = 33), fourth semester physician assistant (n = 27) and fourth semester physical therapy (n = 12) graduate students participated in the study. Participants were stratified by discipline and randomized into control (n = 38) and experimental groups (n = 34). At baseline and at study completion, all participants completed an original, investigator-developed survey that measured improvement in selected Interprofessional Education Collaborative (IPEC) competencies and the Readiness for Interprofessional Learning Scale (RIPLS). The experimental group had statistically significantly greater odds of improving on a variety of IPEC competencies and RIPLS items. The use of a single, interprofessional educational activity resulted in having a greater awareness of other professions' scopes of practice, what other professions have to offer a given patient and how different professions can collaborate in patient care.

  17. Classes of Split-Plot Response Surface Designs for Equivalent Estimation

    NASA Technical Reports Server (NTRS)

    Parker, Peter A.; Kowalski, Scott M.; Vining, G. Geoffrey

    2006-01-01

    When planning an experimental investigation, we are frequently faced with factors that are difficult or time consuming to manipulate, thereby making complete randomization impractical. A split-plot structure differentiates between the experimental units associated with these hard-to-change factors and others that are relatively easy-to-change and provides an efficient strategy that integrates the restrictions imposed by the experimental apparatus. Several industrial and scientific examples are presented to illustrate design considerations encountered in the restricted randomization context. In this paper, we propose classes of split-plot response designs that provide an intuitive and natural extension from the completely randomized context. For these designs, the ordinary least squares estimates of the model are equivalent to the generalized least squares estimates. This property provides best linear unbiased estimators and simplifies model estimation. The design conditions that allow for equivalent estimation are presented enabling design construction strategies to transform completely randomized Box-Behnken, equiradial, and small composite designs into a split-plot structure.

  18. Instructional Set, Deep Relaxation and Growth Enhancement: A Pilot Study

    ERIC Educational Resources Information Center

    Leeb, Charles; And Others

    1976-01-01

    This study provides experimental evidence that instructional set can influence access to altered states of consciousness. Fifteen male subjects were randomly assigned to three groups, each of which received the same autogenic biofeedback training in hand temperature control, but each group received a different attitudinal set. (Editor)

  19. A Comparative Study of Exact versus Propensity Matching Techniques Using Monte Carlo Simulation

    ERIC Educational Resources Information Center

    Itang'ata, Mukaria J. J.

    2013-01-01

    Often researchers face situations where comparative studies between two or more programs are necessary to make causal inferences for informed policy decision-making. Experimental designs employing randomization provide the strongest evidence for causal inferences. However, many pragmatic and ethical challenges may preclude the use of randomized…

  20. The Effect of Preschool Education on Math Achievement.

    ERIC Educational Resources Information Center

    Vondrak, Maripatricia

    A study examined the effects of preschool attendance on third graders' mathematics achievement. The subjects for the study were randomly selected from 111 third graders from a predominantly low socioeconomic neighborhood in Chicago. All students were from minority groups. The experimental group was comprised of 21 students who had attended…

  1. Children's Ability to Comprehend Main Ideas After Reading Expository Prose.

    ERIC Educational Resources Information Center

    Baumann, James F.

    A study was conducted to evaluate children's ability to comprehend main ideas after reading connected discourse and to develop and validate a straightforward and intuitively simple system for identifying main ideas in prose. Three experimental passages were randomly selected from third and sixth grade social studies textbooks, and education…

  2. Mindful Listening Instruction: Does It Make a Difference

    ERIC Educational Resources Information Center

    Anderson, William Todd

    2013-01-01

    This study examines the effect of mindfulness on student listening. Mindfulness is defined as "the process of noticing novel distinctions." Fifth grade students (N = 38) at a single school participated in this study, which used a posttest-only, random selection experimental design. The Independent Variable was exposure to mindful…

  3. Experimental Treatment of Early Stuttering: A Preliminary Study

    ERIC Educational Resources Information Center

    Franken, Marie-Christine J.; Kielstra-Van der Schalk, Carine J.; Boelens, Harrie

    2005-01-01

    This pilot study compared two treatments for stuttering in preschool-age children. Thirty children were randomly assigned to either a Lidcombe Program (LP) treatment or a Demands and Capacities Model (DCM) treatment. Stuttering frequencies and severity ratings were obtained immediately before and after treatment (12 weeks). The stuttering…

  4. Optimal Design for Regression Discontinuity Studies with Clustering

    ERIC Educational Resources Information Center

    Rhoads, Christopher; Dye, Charles

    2014-01-01

    Recent years have seen an increased interest in quantitative educational research studies that use random assignment (RA) to evaluate the causal impacts of educational interventions (Angrist, 2004). The multi-level structure of the public education system in the United States often leads to experimental designs where naturally occurring clusters…

  5. A controlled, randomized, comparative study of a radiant heat bandage on the healing of stage 3-4 pressure ulcers: a pilot study.

    PubMed

    Thomas, David R; Diebold, Marilyn R; Eggemeyer, Linda M

    2005-01-01

    Pressure ulcers, like other chronic wounds, fail to proceed through an orderly and timely process to produce anatomical or functional integrity. Treatment of pressure ulcers is directed to improving host factors and providing an optimum wound environment. In addition to providing a moist wound environment, it has been theorized that preventing hypothermia in a wound and maintaining a normothermic state might improve wound healing. Forty-one subjects with a stage 3 or stage 4 truncal pressure ulcer >1.0 cm(2) were recruited from outpatient clinics, long-term care nursing homes, and a rehabilitation center. The experimental group was randomized to a radiant-heat dressing device and the control group was randomized to a hydrocolloid dressing, with or without a calcium alginate filler. Subjects were followed until healed or for 12 weeks. Eight subjects (57%) in the experimental group had complete healing of their pressure ulcer compared with 7 subjects (44%) with complete healing in the control group (P = .46). Although a 13% difference in healing rate between the two arms of the study was found, this difference was not statistically significant. At almost all points along the healing curve, the proportion not healed was higher in the control arm.

  6. Set statistics in conductive bridge random access memory device with Cu/HfO{sub 2}/Pt structure

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

    Zhang, Meiyun; Long, Shibing, E-mail: longshibing@ime.ac.cn; Wang, Guoming

    2014-11-10

    The switching parameter variation of resistive switching memory is one of the most important challenges in its application. In this letter, we have studied the set statistics of conductive bridge random access memory with a Cu/HfO{sub 2}/Pt structure. The experimental distributions of the set parameters in several off resistance ranges are shown to nicely fit a Weibull model. The Weibull slopes of the set voltage and current increase and decrease logarithmically with off resistance, respectively. This experimental behavior is perfectly captured by a Monte Carlo simulator based on the cell-based set voltage statistics model and the Quantum Point Contact electronmore » transport model. Our work provides indications for the improvement of the switching uniformity.« less

  7. Using Natural Experiments to Study the Impact of Media on the Family

    ERIC Educational Resources Information Center

    Price, Joseph; Dahl, Gordon B.

    2012-01-01

    The randomized trial is the gold standard in scientific research and is used by several fields to study the effects of media. Although useful for studying the immediate response to media exposure, the experimental approach is not well suited to studying long-term effects or behavior outside the laboratory. The "natural experiment" approach, a…

  8. Quasi-experimental study designs series-paper 4: uses and value.

    PubMed

    Bärnighausen, Till; Tugwell, Peter; Røttingen, John-Arne; Shemilt, Ian; Rockers, Peter; Geldsetzer, Pascal; Lavis, John; Grimshaw, Jeremy; Daniels, Karen; Brown, Annette; Bor, Jacob; Tanner, Jeffery; Rashidian, Arash; Barreto, Mauricio; Vollmer, Sebastian; Atun, Rifat

    2017-09-01

    Quasi-experimental studies are increasingly used to establish causal relationships in epidemiology and health systems research. Quasi-experimental studies offer important opportunities to increase and improve evidence on causal effects: (1) they can generate causal evidence when randomized controlled trials are impossible; (2) they typically generate causal evidence with a high degree of external validity; (3) they avoid the threats to internal validity that arise when participants in nonblinded experiments change their behavior in response to the experimental assignment to either intervention or control arm (such as compensatory rivalry or resentful demoralization); (4) they are often well suited to generate causal evidence on long-term health outcomes of an intervention, as well as nonhealth outcomes such as economic and social consequences; and (5) they can often generate evidence faster and at lower cost than experiments and other intervention studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. All-optical animation projection system with rotating fieldstone.

    PubMed

    Ishii, Yuko; Takayama, Yoshihisa; Kodate, Kashiko

    2007-06-11

    A simple and compact rewritable holographic memory system using a fieldstone of Ulexite is proposed. The role of the fieldstone is to impose random patterns on the reference beam to record plural images with the random-reference multiplexing scheme. The operations for writing and reading holograms are carried out by simply rotating the fieldstone in one direction. One of the features of this approach is found in a way to generate random patterns without computer drawings. The experimental study confirms that our system enables the smooth readout of the stored images one after another so that the series of reproduced images are projected as an animation.

  10. All-optical animation projection system with rotating fieldstone

    NASA Astrophysics Data System (ADS)

    Ishii, Yuko; Takayama, Yoshihisa; Kodate, Kashiko

    2007-06-01

    A simple and compact rewritable holographic memory system using a fieldstone of Ulexite is proposed. The role of the fieldstone is to impose random patterns on the reference beam to record plural images with the random-reference multiplexing scheme. The operations for writing and reading holograms are carried out by simply rotating the fieldstone in one direction. One of the features of this approach is found in a way to generate random patterns without computer drawings. The experimental study confirms that our system enables the smooth readout of the stored images one after another so that the series of reproduced images are projected as an animation.

  11. Lap Top Computers and the Learning Disabled Student. A Study of the Value of Portable Computers to the Writing Progress of Students with Fine Motor Problems. No. 193.

    ERIC Educational Resources Information Center

    Yau, Maria; And Others

    Fifty-six Toronto (Ontario, Canada) seventh-grade and eighth-grade learning-disabled students whose handwriting was very difficult to read were randomly assigned to either an experimental or comparison group. Experimental group students were loaned a portable computer to use freely at school and at home during the course of the experiment.…

  12. Simulation-based Randomized Comparative Assessment of Out-of-Hospital Cardiac Arrest Resuscitation Bundle Completion by Emergency Medical Service Teams Using Standard Life Support or an Experimental Automation-assisted Approach.

    PubMed

    Choi, Bryan; Asselin, Nicholas; Pettit, Catherine C; Dannecker, Max; Machan, Jason T; Merck, Derek L; Merck, Lisa H; Suner, Selim; Williams, Kenneth A; Jay, Gregory D; Kobayashi, Leo

    2016-12-01

    Effective resuscitation of out-of-hospital cardiac arrest (OHCA) patients is challenging. Alternative resuscitative approaches using electromechanical adjuncts may improve provider performance. Investigators applied simulation to study the effect of an experimental automation-assisted, goal-directed OHCA management protocol on EMS providers' resuscitation performance relative to standard protocols and equipment. Two-provider (emergency medical technicians (EMT)-B and EMT-I/C/P) teams were randomized to control or experimental group. Each team engaged in 3 simulations: baseline simulation (standard roles); repeat simulation (standard roles); and abbreviated repeat simulation (reversed roles, i.e., basic life support provider performing ALS tasks). Control teams used standard OHCA protocols and equipment (with high-performance cardiopulmonary resuscitation training intervention); for second and third simulations, experimental teams performed chest compression, defibrillation, airway, pulmonary ventilation, vascular access, medication, and transport tasks with goal-directed protocol and resuscitation-automating devices. Videorecorders and simulator logs collected resuscitation data. Ten control and 10 experimental teams comprised 20 EMT-B's; 1 EMT-I, 8 EMT-C's, and 11 EMT-P's; study groups were not fully matched. Both groups suboptimally performed chest compressions and ventilations at baseline. For their second simulations, control teams performed similarly except for reduced on-scene time, and experimental teams improved their chest compressions (P=0.03), pulmonary ventilations (P<0.01), and medication administration (P=0.02); changes in their performance of chest compression, defibrillation, airway, and transport tasks did not attain significance against control teams' changes. Experimental teams maintained performance improvements during reversed-role simulations. Simulation-based investigation into OHCA resuscitation revealed considerable variability and improvable deficiencies in small EMS teams. Goal-directed, automation-assisted OHCA management augmented select resuscitation bundle element performance without comprehensive improvement.

  13. Self-Organization of Temporal Structures — A Possible Solution for the Intervention Problem

    NASA Astrophysics Data System (ADS)

    von Lucadou, Walter

    2006-10-01

    The paper presents an experiment that is a conceptual replication of two earlier experiments which demonstrate entanglement correlations between a quantum physical random process and certain psychological variables of human observers. In the present study button-pushes were used as psychological variables. The button-pushes were performed by the subject with his or her left or right hand in order to "control" (according to the instruction) a random process that could be observed on a display. Each button-push started the next random event which, however, in reality, was independent of the button-pushes. The study consists of three independent sets of data (n = 386) that were gained with almost fee same apparatus in three different experimental situations. The first data set serves as reference. It was an automatic control-run without subjects. The second set was produced mainly by subjects who asked for taking part in a para-psychological experiment and who visited the "Parapsychological Counseling Office" in Freiburg especially for this purpose. Most of them were highly motivated persons who wanted to test their "psi ability". In this case the number of runs could be selected by the subjects before the experimental session. The third set of data (of the same size) was collected during two public exhibitions (at Basel and at Freiburg) where the visitors had the opportunity to participate in a "PK experiment". In this case the number of trials and runs was fixed in advance, but the duration of the experiment was dependent of the speed of button-pushes. The results corroborate the previous studies. The specific way how the subjects pushed the buttons is highly significantly correlated with the independent random process. This correlation shows up for the momentarily generated random events as well as for the previous and the later runs during the experimental session. In a strict sense, only the correlations with the future random events can be interpreted as non-local correlations. The structure of the data, however, allows the conclusion, that all observed correlations can be considered as entanglement-correlations. The number of entanglement-correlations was significantly higher for the highly motivated group (data set 2) than for the unselected group of the exhibition participants (data set 3). The latter, however, where not completely unsuccessful: A subgroup who showed "innovative" behavior also showed significant entanglement-correlations. It could further be shown, that the structure of the matrix of entanglement-correlations is not stable in time and changes if the experiment is repeated. In comparison with previous correlation-experiments, no decline of the effect size was observed. These results are in agreement with the predictions of the "Weak Quantum Theory (WQT)" and the "Model of Pragmatic Information (MPI)". These models interpret the measured correlations as entanglement-correlations within a self-organizing, organizationally closed, psycho-physical system that exist during a certain time-interval (as long as the system is active). The entanglement-correlations cannot be considered as a causal influence (in the sense of a PK-Influence) and thus are called "micro-synchronicity". After a short introduction (1.), the question is discussed how non-local correlations can be created in psycho-physical systems (2.). In chapter (3.) the description of the experimental setting is given and the apparatus (4.) and randomness test of the random event generator (5.) are described. Additionally, an overview of the structure of the data is given (6.) and the analysis methods are described (7.). In chapter (8.) the experimental hypotheses are formulated and the results are reported (9.). After the discussion of the results (10.) the conclusions (11).) of the study are presented.

  14. Effect of Music Therapy on Patients' Anxiety and Hemodynamic Parameters During Coronary Angioplasty: A Randomized Controlled Trial.

    PubMed

    Forooghy, Masoumeh; Mottahedian Tabrizi, Elaheh; Hajizadeh, Ebrahim; Pishgoo, Bahram

    2015-06-01

    A cardiac catheterization laboratory can be a frightening environment and music can be a supportive source of environmental sound that stimulates and maintains relaxation. However, the results of studies are conflicting in this regard. The aim of this study was to investigate the effect of music therapy on patients' anxiety and hemodynamic parameters during percutaneous transluminal coronary angioplasty. This was a randomized controlled trial, conducted in the Catheterization Laboratory Unit of Baqiyatallah Hospital, in Tehran, Iran. A sample of 64 patients, who were planned to undergo coronary angioplasty, was recruited. Patients were randomly allocated to either the control or the experimental groups. In the experimental group, patients received a 20 to 40-minute music therapy intervention, consisting of light instrumental music albums by Johann Sebastian Bach and Mariko Makino. Patients in the control group received the routine care of the study setting, which consisted of no music therapy intervention. Study data were collected by a demographic questionnaire, the Spielberger's State Anxiety Inventory, and a data sheet for documenting hemodynamic parameters. Chi-square, independent-samples t tests, paired-samples t-test and repeated measures analysis of variance were used to analyze the data. Before the intervention, the study groups did not differ significantly in terms of anxiety level and hemodynamic parameters. Moreover, the differences between the two groups, regarding hemodynamic parameters, were not significant after the intervention (P > 0.05). However, the level of post-intervention anxiety in the experimental group was significantly lower than the control group (32.06 ± 8.57 and 38.97 ± 12.77, respectively; P = 0.014). Compared with the baseline readings, the level of anxiety in the control group did not change significantly after the study (41.91 ± 9.88 vs. 38.97 ± 12.77; P = 0.101); however, in the experimental group, the level of post-intervention anxiety was significantly lower than the pretest readings (32.06 ± 8.57 vs. 41.16 ± 10.6; P = 0.001). Music therapy is a safe, simple, inexpensive, and non-invasive nursing intervention, which can significantly alleviate patients' anxiety during coronary angioplasty.

  15. Random field assessment of nanoscopic inhomogeneity of bone.

    PubMed

    Dong, X Neil; Luo, Qing; Sparkman, Daniel M; Millwater, Harry R; Wang, Xiaodu

    2010-12-01

    Bone quality is significantly correlated with the inhomogeneous distribution of material and ultrastructural properties (e.g., modulus and mineralization) of the tissue. Current techniques for quantifying inhomogeneity consist of descriptive statistics such as mean, standard deviation and coefficient of variation. However, these parameters do not describe the spatial variations of bone properties. The objective of this study was to develop a novel statistical method to characterize and quantitatively describe the spatial variation of bone properties at ultrastructural levels. To do so, a random field defined by an exponential covariance function was used to represent the spatial uncertainty of elastic modulus by delineating the correlation of the modulus at different locations in bone lamellae. The correlation length, a characteristic parameter of the covariance function, was employed to estimate the fluctuation of the elastic modulus in the random field. Using this approach, two distribution maps of the elastic modulus within bone lamellae were generated using simulation and compared with those obtained experimentally by a combination of atomic force microscopy and nanoindentation techniques. The simulation-generated maps of elastic modulus were in close agreement with the experimental ones, thus validating the random field approach in defining the inhomogeneity of elastic modulus in lamellae of bone. Indeed, generation of such random fields will facilitate multi-scale modeling of bone in more pragmatic details. Copyright © 2010 Elsevier Inc. All rights reserved.

  16. The analgesic effects of exogenous melatonin in humans.

    PubMed

    Andersen, Lars Peter Holst

    2016-10-01

    The hormone, melatonin is produced with circadian rhythm by the pineal gland in humans. The melatonin rhythm provides an endogenous synchronizer, modulating e.g. blood pressure, body temperature, cortisol rhythm, sleep-awake-cycle, immune function and anti-oxidative defence. Interestingly, a number of experimental animal studies demonstrate significant dose-dependent anti-nociceptive effects of exogenous melatonin. Similarly, recent experimental- and clinical studies in humans indicate significant analgesic effects. In study I, we systematically reviewed all randomized studies investigating clinical effects of perioperative melatonin. Meta-analyses demonstrated significant analgesic and anxiolytic effects of melatonin in surgical patients, equating reductions of 20 mm and 19 mm, respectively on a VAS, compared with placebo. Profound heterogeneity between the included studies was, however, present. In study II, we aimed to investigate the analgesic, anti-hyperalgesic and anti-inflammatory effects of exogenous melatonin in a validated human inflammatory pain model, the human burn model. The study was performed as a randomized, double blind placebo-controlled crossover study. Primary outcomes were pain during the burn injury and areas of secondary hyperalgesia. No significant effects of exogenous melatonin were observed with respect to primary or secondary outcomes, compared to placebo. Study III and IV estimated the pharmacokinetic variables of exogenous melatonin. Oral melatonin demonstrated a t max value of 41 minutes. Bioavailability of oral melatonin was only 3%. Elimination t 1/2 were approximately 45 minutes following both oral and intravenous administration, respectively. High-dose intravenous melatonin was not associated with increased sedation, in terms of simple reaction times, compared to placebo. Similarly, no other adverse effects were reported. In Study V, we aimed to re-analyse data obtained from a randomized analgesic drug trial by a selection of standard statistical test. Furthermore, we presented an integrated assessment method of longitudinally measured pain intensity and opioid consumption. Our analyses documented that the employed statistical method impacted the statistical significance of post-operative analgesic outcomes. Furthermore, the novel integrated assessment method combines two interdependent outcomes, lowers the risk of type 2 errors, increases the statistical power, and provides a more accurate description of post-operative analgesic efficacy. Exogenous melatonin may offer an effective and safe analgesic drug. At this moment, however, the results of human studies have been contradictory. High-quality randomized experimental- and clinical studies are still needed to establish a "genuine" analgesic effect of the drug in humans. Other perioperative effects of exogenous melatonin should also be investigated, before melatonin can be introduced for clinical routine use in surgical patients. Despite promising experimental and clinical findings, several unanswered questions also relate to optimal dosage, timing of administration and administration route of exogenous melatonin.

  17. Do bacterial cell numbers follow a theoretical Poisson distribution? Comparison of experimentally obtained numbers of single cells with random number generation via computer simulation.

    PubMed

    Koyama, Kento; Hokunan, Hidekazu; Hasegawa, Mayumi; Kawamura, Shuso; Koseki, Shigenobu

    2016-12-01

    We investigated a bacterial sample preparation procedure for single-cell studies. In the present study, we examined whether single bacterial cells obtained via 10-fold dilution followed a theoretical Poisson distribution. Four serotypes of Salmonella enterica, three serotypes of enterohaemorrhagic Escherichia coli and one serotype of Listeria monocytogenes were used as sample bacteria. An inoculum of each serotype was prepared via a 10-fold dilution series to obtain bacterial cell counts with mean values of one or two. To determine whether the experimentally obtained bacterial cell counts follow a theoretical Poisson distribution, a likelihood ratio test between the experimentally obtained cell counts and Poisson distribution which parameter estimated by maximum likelihood estimation (MLE) was conducted. The bacterial cell counts of each serotype sufficiently followed a Poisson distribution. Furthermore, to examine the validity of the parameters of Poisson distribution from experimentally obtained bacterial cell counts, we compared these with the parameters of a Poisson distribution that were estimated using random number generation via computer simulation. The Poisson distribution parameters experimentally obtained from bacterial cell counts were within the range of the parameters estimated using a computer simulation. These results demonstrate that the bacterial cell counts of each serotype obtained via 10-fold dilution followed a Poisson distribution. The fact that the frequency of bacterial cell counts follows a Poisson distribution at low number would be applied to some single-cell studies with a few bacterial cells. In particular, the procedure presented in this study enables us to develop an inactivation model at the single-cell level that can estimate the variability of survival bacterial numbers during the bacterial death process. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Adequacy of different experimental designs for eucalyptus spacing trials in Portuguese environmental conditions

    Treesearch

    Paula Soares; Margarida Tome

    2000-01-01

    In Portugal, several eucalyptus spacing trials cover a relatively broad range of experimental designs: trials with a non-randomized block design with plots of different size and number of trees per plot; trials based on a non-systematic design in which spacings were randomized resulting in a factorial arrangement with plots of different size and shape and equal number...

  19. Social and Clinical Effects of a Leisure Program on Adults with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Garcia-Villamisar, Domingo; Dattilo, John

    2011-01-01

    Using a pre-test, post-test experimental design, effects of a 1-year group leisure program were examined on 31 participants (20 male and 11 female), ages 27-38 (M = 32.05 at start of program), with an autism spectrum disorder (ASD) diagnosis randomly assigned to the experimental condition and a group of 20 adults with ASD randomly assigned to the…

  20. Sampling large random knots in a confined space

    NASA Astrophysics Data System (ADS)

    Arsuaga, J.; Blackstone, T.; Diao, Y.; Hinson, K.; Karadayi, E.; Saito, M.

    2007-09-01

    DNA knots formed under extreme conditions of condensation, as in bacteriophage P4, are difficult to analyze experimentally and theoretically. In this paper, we propose to use the uniform random polygon model as a supplementary method to the existing methods for generating random knots in confinement. The uniform random polygon model allows us to sample knots with large crossing numbers and also to generate large diagrammatically prime knot diagrams. We show numerically that uniform random polygons sample knots with large minimum crossing numbers and certain complicated knot invariants (as those observed experimentally). We do this in terms of the knot determinants or colorings. Our numerical results suggest that the average determinant of a uniform random polygon of n vertices grows faster than O(e^{n^2}) . We also investigate the complexity of prime knot diagrams. We show rigorously that the probability that a randomly selected 2D uniform random polygon of n vertices is almost diagrammatically prime goes to 1 as n goes to infinity. Furthermore, the average number of crossings in such a diagram is at the order of O(n2). Therefore, the two-dimensional uniform random polygons offer an effective way in sampling large (prime) knots, which can be useful in various applications.

  1. Midstream clean-catch urine collection in newborns: a randomized controlled study.

    PubMed

    Altuntas, Nilgun; Tayfur, Asli Celebi; Kocak, Mesut; Razi, Hasan Cem; Akkurt, Serpil

    2015-05-01

    We aimed to evaluate a recently defined technique based on bladder stimulation and paravertebral lumbar massage maneuvers in collecting a midstream clean-catch urine sample in newborns. A total of 127 term newborns were randomly assigned either to the experimental group or the control group. Twenty-five minutes after feeding, the genital and perineal areas of the babies were cleaned. The babies were held under the armpits with legs dangling. Bladder stimulation and lumbar paravertebral massage maneuvers were only applied to the babies in the experimental group. Success was defined as collection of a urine sample within 5 min of starting the stimulation maneuvers in the experimental group and of holding under the armpits in the control group. The success rate of urine collection was significantly higher in the experimental group (78%) than in the control group (33%; p < 0.001). The median time (interquartile range) for sample collection was 60 s (64.5 s) in the experimental group and 300 s (95 s) in the control group (p < 0.0001). Contamination rates were similar in both groups (p = 0.770). We suggest that bladder stimulation and lumbar paravertebral massage is a safe, quick, and effective way of collecting midstream clean-catch urine in newborns.

  2. Experimental Infection with Sporulated Oocysts of Eimeria maxima (Apicomplexa: Eimeriidae) in Broiler

    PubMed Central

    Brito, Luciana da S.; Pereira, Elder N.; da Silva, Augusta A.; Bentivóglio Costa Silva, Vinícius; Freitas, Fagner L. da C.

    2014-01-01

    Through this study we assessed the metabolic and pathological changes in broilers experimentally infected with oocysts of Eimeria maxima. To perform the experiment, we used 150 broiler strain cooB males, with ten days of age, were randomized according to weight and randomly assigned to two experimental groups: the control group was inoculated with 0.5 mL of distilled water; the infected group inoculated with 0.5 mL of solution containing 5 × 104 sporulated oocysts of Eimeria maxima. The live performance was evaluated on day 0 (day of inoculation), 5°, 10°, 15°, 25°, and 35° dpi, being slaughtered by cervical dislocation, fifteen birds/group. Although the sum in meat production was higher in the control group, the weight of the heart and gizzard of the experimental animals showed no significant difference, while the liver had difference on day 5°, 15°, and 35° dpi. The pathologic evaluation showed congested mucosa and presence of large amounts of mucus at 6 dpi. Therefore, it is concluded that the dose of 5 × 104  E. maxima inoculated in the experimental group was enough to cause harm to the animal organism. PMID:26464925

  3. Multivariate analysis: greater insights into complex systems

    USDA-ARS?s Scientific Manuscript database

    Many agronomic researchers measure and collect multiple response variables in an effort to understand the more complex nature of the system being studied. Multivariate (MV) statistical methods encompass the simultaneous analysis of all random variables (RV) measured on each experimental or sampling ...

  4. [Clinical and experimental study on effect of qinbal ointment in treating psoriasis in the active stage of blood-heat syndrome type].

    PubMed

    Xu, Jia; Zhang, Cang; Qu, Xing

    2009-07-01

    To investigate and compare the efficacy and safety of two kinds of Qinbai ointment prepared conventionally and finely (C-QBO and F-QBO) in treating psoriasis in the active stage of blood-heat syndrome type, and to observe their influences on vaginal epithelial cell mitosis, also on keratinization of caudal flakes in mice. Adopting randomized, single-blinded, controlled design, 93 patients administered orally with Liangxue Huoxue Decoction were randomized into three groups treated externally with C-QBO, F-QBO and white vaseline respectively, applied twice a day for 8 weeks. The safety was checked and the changes of modified psoriasis area severity index (PASI), as well as the conditions of skin lesions (size, erythema, infiltration, squama, and itching) and symptom improving time were compared. Experimental study 1: Mice were randomized into the model group, the C-QBO group, the F-QBO group and the blank group, 7 in each group. Their vaginal epithelial cell mitosis indices were compared after 3 days of treatment with corresponding remedies. Experimental study 2: Mice were randomized into the C-QBO group, the F-QBO group and the blank group, 7 in each group. After the mice had been treated with corresponding remedies for 28 days, the granular layer formation in their caudal scales was compared. The markedly effective rate was 63.3% (25/30) in the C-QBO group, 66.7% (20/30) in the F-QBO group, and 36.7% (11/30) in the control group. No statistical difference was showen between the two QBO treated groups (P > 0.05), but that in both of them was significantly different from that in the control group (P < 0.05). PASI scores lowered after treatment in all the three groups (P < 0.01), but the improvement in the two QBO groups was better than that in the control group (P < 0.05); the conditions of skin lesion were improved in all groups, but the improvements were more significant in the two QBO groups in terms of squama, infiltration and itching (P < 0.05), in aspects of improving time on erythema, infiltration and itching, especially the itching, F-QBO was superior to the C-QBO. Experimental study 1: The mitosis index in both QBO groups was lower than that in the blank group and the model group (P < 0.01). Experimental study 2: Number of scales with granular layer formation was higher in the two QBO groups than in the blank group (P < 0.01). C-QBO and F-QBO can effectively relieve the skin lesion of psoriasis patients in the active stage of blood-heat type, and they could also promote the formation of epithelial granular layer in the caudal scales of mice.

  5. An Investigation of Factors Influencing Learning in the Mentally Retarded, and Their Use in the Design of Instructional Materials; Effects of a Set for Delayed Response on Recall by MR's. Interim Report.

    ERIC Educational Resources Information Center

    Seitz, Sue; Morris, Dan

    In a study on short term memory, 32 educable mentally retarded subjects (mean IQ 62.68, mean mental age 103.78 months) were randomly assigned to each of the four experimental conditions. An automated machine presented the stimuli (32 three-letter words) and the interference items (a list of random numbers read aloud between stimuli presentations).…

  6. Experimental human influenza: observations from studies of influenza antivirals.

    PubMed

    Hayden, Frederick G

    2012-01-01

    Randomized, placebo-controlled trials have been conducted for nearly five decades in experimentally induced human influenza infections to assess the effectiveness, tolerability and pharmacological properties of influenza antivirals. The results of such studies have not only provided key proof-of-concept data to facilitate drug development but also contributed to our understanding of influenza pathogenesis and transmission. The lack of availability of contemporary, safety-tested virus inoculation pools in recent years needs to be resolved in order to avoid hindering the development of new drugs and vaccines.

  7. [Problems of study designs with randomization, blinding and placebos].

    PubMed

    Heusser, P

    1999-04-01

    As randomised double-blind trials are not rarely demanded as a prerequisite for the scientific acceptance of complementary medicine, the author has analysed the soundness of this demand on the basis of the international literature. As a result there appeared a number of methodological, practical and ethical problems which question the theoretically deduced primal value of this study design relative to the needs of medical practice and of health insurance issues. The experimental instruments of randomisation, blinding and placebo deliberately exclude essential therapeutic factors which are integral elements of complementary medical concepts; therefore, it is suggested to supplement quantitatively and collectively oriented experimental research by non-experimental procedures, which adequately reflect the context- and practice-related individual reality.

  8. Effects of Problem-Solving Method on Secondary School Students' Achievement and Retention in Social Studies, in Ekiti State, Nigeria

    ERIC Educational Resources Information Center

    Abdu-Raheem, B. O.

    2012-01-01

    This study investigated the effects of problem-solving method of teaching on secondary school students' achievement and retention in Social Studies. The study adopted the quasi-experimental, pre-test, post-test, control group design. The sample for the study consisted of 240 Junior Secondary School Class II students randomly selected from six…

  9. Effectiveness of Wii-based rehabilitation in stroke: A randomized controlled study.

    PubMed

    Karasu, Ayça Utkan; Batur, Elif Balevi; Karataş, Gülçin Kaymak

    2018-05-08

    To investigate the efficacy of Nintendo Wii Fit®-based balance rehabilitation as an adjunc-tive therapy to conventional rehabilitation in stroke patients. During the study period, 70 stroke patients were evaluated. Of these, 23 who met the study criteria were randomly assigned to either the experimental group (n = 12) or the control group (n = 11) by block randomization. Primary outcome measures were Berg Balance Scale, Functional Reach Test, Postural Assessment Scale for Stroke Patients, Timed Up and Go Test and Static Balance Index. Secondary outcome measures were postural sway, as assessed with Emed-X, Functional Independence Measure Transfer and Ambulation Scores. An evaluator who was blinded to the groups made assessments immediately before (baseline), immediately after (post-treatment), and 4 weeks after completion of the study (follow-up). Group-time interaction was significant in the Berg Balance Scale, Functional Reach Test, anteroposterior and mediolateral centre of pressure displacement with eyes open, anteroposterior centre of pressure displacement with eyes closed, centre of pressure displacement during weight shifting to affected side, to unaffected side and total centre of pressure displacement during weight shifting. Demonstrating significant group-time interaction in those parameters suggests that, while both groups exhibited significant improvement, the experimental group showed greater improvement than the control group. Virtual reality exercises with the Nintendo Wii system could represent a useful adjunctive therapy to traditional treatment to improve static and dynamic balance in stroke patients.

  10. Self-regulation of brain activity in patients with postherpetic neuralgia: a double-blind randomized study using real-time FMRI neurofeedback.

    PubMed

    Guan, Min; Ma, Lijia; Li, Li; Yan, Bin; Zhao, Lu; Tong, Li; Dou, Shewei; Xia, Linjie; Wang, Meiyun; Shi, Dapeng

    2015-01-01

    A pilot study has shown that real-time fMRI (rtfMRI) neurofeedback could be an alternative approach for chronic pain treatment. Considering the relative small sample of patients recruited and not strictly controlled condition, it is desirable to perform a replication as well as a double-blinded randomized study with a different control condition in chronic pain patients. Here we conducted a rtfMRI neurofeedback study in a subgroup of pain patients - patients with postherpetic neuralgia (PHN) and used a different sham neurofeedback control. We explored the feasibility of self-regulation of the rostral anterior cingulate cortex (rACC) activation in patients with PHN through rtfMRI neurofeedback and regulation of pain perception. Sixteen patients (46-71 years) with PHN were randomly allocated to a experimental group (n = 8) or a control group (n = 8). 2 patients in the control group were excluded for large head motion. The experimental group was given true feedback information from their rACC whereas the control group was given sham feedback information from their posterior cingulate cortex (PCC). All subjects were instructed to perform an imagery task to increase and decrease activation within the target region using rtfMRI neurofeedback. Online analysis showed 6/8 patients in the experimental group were able to increase and decrease the blood oxygen level dependent (BOLD) fMRI signal magnitude during intermittent feedback training. However, this modulation effect was not observed in the control group. Offline analysis showed that the percentage of BOLD signal change of the target region between the last and first training in the experimental group was significantly different from the control group's and was also significantly different than 0. The changes of pain perception reflected by numerical rating scale (NRS) in the experimental group were significantly different from the control group. However, there existed no significant correlations between BOLD signal change and NRS change. Patients with PHN could learn to voluntarily control over activation in rACC through rtfMRI neurofeedback and alter their pain perception level. The present study may provide new evidence that rtfMRI neurofeedback training may be a supplemental approach for chronic clinical pain management.

  11. Self-Regulation of Brain Activity in Patients with Postherpetic Neuralgia: A Double-Blind Randomized Study Using Real-Time fMRI Neurofeedback

    PubMed Central

    Li, Li; Yan, Bin; Zhao, Lu; Tong, Li; Dou, Shewei; Xia, Linjie; Wang, Meiyun; Shi, Dapeng

    2015-01-01

    Background A pilot study has shown that real-time fMRI (rtfMRI) neurofeedback could be an alternative approach for chronic pain treatment. Considering the relative small sample of patients recruited and not strictly controlled condition, it is desirable to perform a replication as well as a double-blinded randomized study with a different control condition in chronic pain patients. Here we conducted a rtfMRI neurofeedback study in a subgroup of pain patients – patients with postherpetic neuralgia (PHN) and used a different sham neurofeedback control. We explored the feasibility of self-regulation of the rostral anterior cingulate cortex (rACC) activation in patients with PHN through rtfMRI neurofeedback and regulation of pain perception. Methods Sixteen patients (46–71 years) with PHN were randomly allocated to a experimental group (n = 8) or a control group (n = 8). 2 patients in the control group were excluded for large head motion. The experimental group was given true feedback information from their rACC whereas the control group was given sham feedback information from their posterior cingulate cortex (PCC). All subjects were instructed to perform an imagery task to increase and decrease activation within the target region using rtfMRI neurofeedback. Results Online analysis showed 6/8 patients in the experimental group were able to increase and decrease the blood oxygen level dependent (BOLD) fMRI signal magnitude during intermittent feedback training. However, this modulation effect was not observed in the control group. Offline analysis showed that the percentage of BOLD signal change of the target region between the last and first training in the experimental group was significantly different from the control group’s and was also significantly different than 0. The changes of pain perception reflected by numerical rating scale (NRS) in the experimental group were significantly different from the control group. However, there existed no significant correlations between BOLD signal change and NRS change. Conclusion Patients with PHN could learn to voluntarily control over activation in rACC through rtfMRI neurofeedback and alter their pain perception level. The present study may provide new evidence that rtfMRI neurofeedback training may be a supplemental approach for chronic clinical pain management. PMID:25848773

  12. 75 FR 39220 - National Institute on Disability and Rehabilitation Research (NIDRR)-Disability and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-08

    ... free to choose experimental, quasi-experimental, case-control, or other applicable research designs...: Nothing in the priority either precludes or requires the use of randomized experimental trials of VR...

  13. Immediate effects of Tuina techniques on working-related musculoskeletal disorder of professional orchestra musicians.

    PubMed

    Sousa, Cláudia Maria; Moreira, Luis; Coimbra, Daniela; Machado, Jorge; Greten, Henry J

    2015-07-01

    Musicians are a prone group to suffer from working-related musculoskeletal disorder (WRMD). Conventional solutions to control musculoskeletal pain include pharmacological treatment and rehabilitation programs but their efficiency is sometimes disappointing. The aim of this research is to study the immediate effects of Tuina techniques on WRMD of professional orchestra musicians from the north of Portugal. We performed a prospective, controlled, single-blinded, randomized study. Professional orchestra musicians with a diagnosis of WRMD were randomly distributed into the experimental group (n=39) and the control group (n=30). During an individual interview, Chinese diagnosis took place and treatment points were chosen. Real acupoints were treated by Tuina techniques into the experimental group and non-specific skin points were treated into the control group. Pain was measured by verbal numerical scale before and immediately after intervention. After one treatment session, pain was reduced in 91.8% of the cases for the experimental group and 7.9% for the control group. Although results showed that Tuina techniques are effectively reducing WRMD in professional orchestra musicians of the north of Portugal, further investigations with stronger measurements, double-blinding designs and bigger simple sizes are needed.

  14. Experimental and Quasi-Experimental Design.

    ERIC Educational Resources Information Center

    Cottrell, Edward B.

    With an emphasis on the problems of control of extraneous variables and threats to internal and external validity, the arrangement or design of experiments is discussed. The purpose of experimentation in an educational institution, and the principles governing true experimentation (randomization, replication, and control) are presented, as are…

  15. Evaluation of the "Energize Your Life!" Social Marketing Campaign Pilot Study to Increase Fruit Intake among Community College Students

    ERIC Educational Resources Information Center

    Shive, Steven E.; Morris, Michelle Neyman

    2006-01-01

    In this study, the authors evaluated the effectiveness of the "Energize Your Life!" social-marketing campaign pilot study to improve knowledge, attitudes, and fruit intake among community college students. The authors used a cross-sectional, quasi-experimental, pre- and posttest design. They randomly selected community college students…

  16. A Study of Reliability of Marking and Absolute Grading in Secondary Schools

    ERIC Educational Resources Information Center

    Abdul Gafoor, K.; Jisha, P.

    2014-01-01

    Using a non-experimental comparative group design in a sample consisting of 100 English teachers randomly selected from 30 secondary schools of a district of Kerala and assigning fifty teachers to groups for marking and grading, this study compares inter and intra-individual reliability in marking and absolute grading. Studying (1) the in marking…

  17. Learning English through Actions: A Study of Mobile-Assisted Language Learning

    ERIC Educational Resources Information Center

    Liu, Pei-Lin; Chen, Chiu-Jung

    2015-01-01

    This study investigated the impact of taking photos using mobile phones on the English phrase-learning performance of English as a second-language learners. A total of 116 students enrolled in a college in Central Taiwan participated in this study. The participants were divided randomly into two groups: a control group and an experimental group…

  18. The Effect of Using Computer Edutainment on Developing 2nd Primary Graders' Writing Skills

    ERIC Educational Resources Information Center

    Mohammed Abdel Raheem, Azza Ashraf

    2011-01-01

    The present study attempted to examine the effect of using computer edutainment on developing 2nd graders' writing skills. The study comprised thirty-second year primary stage enrolled in Bani Hamad primary governmental school, Minia governorate. The study adopted the quasi-experimental design. Thirty participants were randomly assigned to one…

  19. The Effectiveness of the Harm Reduction Group Therapy Based on Bandura's Self-Efficacy Theory on Risky Behaviors of Drug-Dependent Sex Worker Women.

    PubMed

    Rabani-Bavojdan, Marjan; Rabani-Bavojdan, Mozhgan; Rajabizadeh, Ghodratollah; Kaviani, Nahid; Bahramnejad, Ali; Ghaffari, Zohreh; Shafiei-Bafti, Mehdi

    2017-07-01

    The aim of this study was to investigate the effectiveness of the harm reduction group therapy based on Bandura's self-efficacy theory on risky behaviors of sex workers in Kerman, Iran. A quasi-experimental two-group design (a random selection with pre-test and post-test) was used. A risky behaviors questionnaire was used to collect. The sample was selected among sex workers referring to drop-in centers in Kerman. Subjects were allocated to two groups and were randomly classified into two experimental and control groups. The sample group consisted of 56 subjects. The experimental design was carried out during 12 sessions, and the post-test was performed one month and two weeks after the completion of the sessions. The results were analyzed statistically. By reducing harm based on Bandura's self-efficacy theory, the risky behaviors of the experimental group, including injection behavior, sexual behavior, violence, and damage to the skin, were significantly reduced in the pre-test compared to the post-test (P < 0.010). The harm reduction group therapy based on Bandura's self-efficacy theory can reduce the risky behaviors of sex workers.

  20. Randomized trials published in Chinese or Western journals: comparative empirical analysis.

    PubMed

    Purgato, Marianna; Cipriani, Andrea; Barbui, Corrado

    2012-06-01

    A major concern to the inclusion in systematic reviews of studies originating in China and published in Chinese journals refers to the quality of study reporting. In this systematic survey of randomized trials, we compared the characteristics of studies published in Chinese journals with those of studies published in Western journals. We included 69 studies comparing citalopram with other antidepressant drugs in the treatment of major depression. Of these, 37 (54%) were published in Chinese journals. The standard of reporting was generally poor in both Western and Chinese studies. In some Chinese studies, the generation of the randomization sequence raised concern about their experimental nature, and in almost all included studies, the concealment of allocation was not properly described. Blinding was seldom adopted in Chinese studies, and the risk of sponsorship bias was uncertain because Chinese studies did not report any financial support. In most Western studies, outcome data were selectively and incompletely reported. Pooling together all trials revealed that citalopram was similarly effective in comparison with all other antidepressant drugs both in Western studies (standardized mean difference, -0.04; 95% confidence interval, -0.15 to 0.06) and in Chinese studies (standardized mean difference, -0.08, 95% confidence interval, -0.18 to 0.02). Randomized controlled trials published in Chinese journals represent most of the studies included in this review. This suggests that omitting to search biomedical databases originating from China would systematically exclude a relevant proportion of randomized trials published in Chinese journals, with a risk of random error or bias. The increasing inclusion of Chinese studies in systematic reviews reinforces the need to check the quality of randomized trials that are meta-analyzed.

  1. Random Assignment: Practical Considerations from Field Experiments.

    ERIC Educational Resources Information Center

    Dunford, Franklyn W.

    1990-01-01

    Seven qualitative issues associated with randomization that have the potential to weaken or destroy otherwise sound experimental designs are reviewed and illustrated via actual field experiments. Issue areas include ethics and legality, liability risks, manipulation of randomized outcomes, hidden bias, design intrusiveness, case flow, and…

  2. Experimental task-based optimization of a four-camera variable-pinhole small-animal SPECT system

    NASA Astrophysics Data System (ADS)

    Hesterman, Jacob Y.; Kupinski, Matthew A.; Furenlid, Lars R.; Wilson, Donald W.

    2005-04-01

    We have previously utilized lumpy object models and simulated imaging systems in conjunction with the ideal observer to compute figures of merit for hardware optimization. In this paper, we describe the development of methods and phantoms necessary to validate or experimentally carry out these optimizations. Our study was conducted on a four-camera small-animal SPECT system that employs interchangeable pinhole plates to operate under a variety of pinhole configurations and magnifications (representing optimizable system parameters). We developed a small-animal phantom capable of producing random backgrounds for each image sequence. The task chosen for the study was the detection of a 2mm diameter sphere within the phantom-generated random background. A total of 138 projection images were used, half of which included the signal. As our observer, we employed the channelized Hotelling observer (CHO) with Laguerre-Gauss channels. The signal-to-noise (SNR) of this observer was used to compare different system configurations. Results indicate agreement between experimental and simulated data with higher detectability rates found for multiple-camera, multiple-pinhole, and high-magnification systems, although it was found that mixtures of magnifications often outperform systems employing a single magnification. This work will serve as a basis for future studies pertaining to system hardware optimization.

  3. Device-independent randomness generation from several Bell estimators

    NASA Astrophysics Data System (ADS)

    Nieto-Silleras, Olmo; Bamps, Cédric; Silman, Jonathan; Pironio, Stefano

    2018-02-01

    Device-independent randomness generation and quantum key distribution protocols rely on a fundamental relation between the non-locality of quantum theory and its random character. This relation is usually expressed in terms of a trade-off between the probability of guessing correctly the outcomes of measurements performed on quantum systems and the amount of violation of a given Bell inequality. However, a more accurate assessment of the randomness produced in Bell experiments can be obtained if the value of several Bell expressions is simultaneously taken into account, or if the full set of probabilities characterizing the behavior of the device is considered. We introduce protocols for device-independent randomness generation secure against classical side information, that rely on the estimation of an arbitrary number of Bell expressions or even directly on the experimental frequencies of measurement outcomes. Asymptotically, this results in an optimal generation of randomness from experimental data (as measured by the min-entropy), without having to assume beforehand that the devices violate a specific Bell inequality.

  4. Effect of acclimation training on physiological changes in a randomized controlled trial in hot-humid environment.

    PubMed

    Zhang, Lei; Bao, Ying-chun

    2014-11-01

    This study was aimed to explore the physiological changes and the effect of heat acclimation training via a randomized control trial study. Forty healthy male volunteers were chosen and divided into experimental group and control group randomly. Those in experimental group received heat acclimation training including but not limited to meditation, unarmed run, yoga, and stepping in hot lab environment. And then, subjective feeling, rectal temperature, average skin temperature, and sweat electrolytes concentration were detected in order to describe their physiological changes. Before and after the training, both groups received some tests and their 3 000 m run-race time, nervous reaction time and subjective perception scores were recorded to evaluate the effect of acclimation training. (1) There was no difference in 3 000 m between the 2 groups in the same environment. Subjects' 3 000 m race time in experimental group was obviously shortened than that in control group in room temperature environment (t = 2.326, P < 0.05). And subjects' 3 000 m race time in experimental group was obviously shortened than that in control group in hot-humid environment (t = 4.518, P < 0.01). (2) Subjects' reaction time (RT) in experimental group was shortened than that in control group in room temperature environment (Z = 11.258, P < 0.05). And Subjects' RT in experimental group was sharply shortened than that in control group in hot-humid environment (Z = 6.519, P < 0.01). (3) No difference between the experimental and control groups was observed in subjective perception score (SPS) in room temperature environment. But subjects' SPS in experimental group was obviously lowered than that in control group and in hot-humid environment (t = 17.958, P < 0.01).(4) Anal temperature (AT) was lowered during training, while the change of mean skin temperature (MST) was not significant. Sweat sodium concentration (SSC) was lowered during training. SPS continued to decrease and entered plateau on the 13th day after training.(5) After acclimation training, the working capacity of the experimental group in hot-humid environment was over 85% of that in room temperature environment. While subjects' working capacity in control group in hot-humid environment was about 80% of that in room temperature environment. Hot-humid environment acclimation training improved the working capacity. After training, subjects' working capacity in hot-humid environment remained over 85% of that in room temperature environment, which was higher than that of those subjects who did not take part in training.

  5. Parametric down-conversion with nonideal and random quasi-phase-matching

    NASA Astrophysics Data System (ADS)

    Yang, Chun-Yao; Lin, Chun; Liljestrand, Charlotte; Su, Wei-Min; Canalias, Carlota; Chuu, Chih-Sung

    2016-05-01

    Quasi-phase-matching (QPM) has enriched the capacity of parametric down-conversion (PDC) in generating biphotons for many fundamental tests and advanced applications. However, it is not clear how the nonidealities and randomness in the QPM grating of a parametric down-converter may affect the quantum properties of the biphotons. This paper intends to provide insights into the interplay between PDC and nonideal or random QPM structures. Using a periodically poled nonlinear crystal with short periodicity, we conduct experimental and theoretical studies of PDC subject to nonideal duty cycle and random errors in domain lengths. We report the observation of biphotons emerging through noncritical birefringent-phasematching, which is impossible to occur in PDC with an ideal QPM grating, and a biphoton spectrum determined by the details of nonidealities and randomness. We also observed QPM biphotons with a diminished strength. These features are both confirmed by our theory. Our work provides new perspectives for biphoton engineering with QPM.

  6. An experimental test of the effects of gender constancy on sex typing.

    PubMed

    Arthur, Andrea E; Bigler, Rebecca S; Ruble, Diane N

    2009-12-01

    This study provides an experimental test of the hypothesis that level of gender constancy understanding affects children's sex typing. Preschool-age children (N=62, mean age=47 months) were randomly assigned to experimental lessons that taught that biological traits (including gender) are either fixed (pro-constancy condition) or mutable (anti-constancy condition). Posttests revealed that the lessons were effective; children in the pro-constancy condition showed higher gender constancy and appearance-reality distinction scores than did children in the anti-constancy condition. Sex typing did not, however, differ between treatment conditions at immediate and 3-month posttesting.

  7. Emergency dispatcher assistance decreases time to defibrillation in a public venue: a randomized controlled trial.

    PubMed

    Riyapan, Sattha; Lubin, Jeffrey

    2016-03-01

    We attempted to determine the effect of prearrival instructions that included the specific location of automated external defibrillators (AEDs) in a public venue on the time to defibrillation in a simulated cardiac arrest scenario using untrained bystanders. The study was a randomized controlled trial at an urban shopping mall. Participants were asked to retrieve an AED and come back to defibrillate a mannequin. Only the experimental group received the location of the AED. We measured the percentage of shocks that were delivered in less than 3 minutes from the start of the scenario and also recorded several other time intervals. Thirty-nine participants completed the study, with 20 participants in the experimental group. The median time to defibrillation in the experimental group was 2.6 minutes (interquartile range, 2.4-2.8) which was significantly less than the control group's median time of 5.9 minutes (interquartile range, 4.38-7.65). Ninety percent (95% confidence interval, 68.3%-98.8%) of the participants in the experimental group defibrillated within 3 minutes, which was significantly different from the control group (10.5%; 95% confidence interval, 1.3%-33.1%). In this study, a prearrival protocol providing participants with the location of the nearest AED in a public building resulted in a significant decrease in the time required to deliver a simulated shock. Further investigations in various types of public settings are needed to confirm the results. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. The influence of formative assessments on student motivation, achievement, and conceptual change

    NASA Astrophysics Data System (ADS)

    Yin, Yue

    2005-07-01

    This study connected research on formative assessment, motivation, and conceptual change. In particular, it examined three research questions: (1) Can formative assessment improve students' motivational beliefs? (2) Can formative assessment improve students' achievement in science and bring about conceptual change? and (3) Are students' science achievement and conceptual change correlated with their motivational beliefs? Formative assessment in this study refers to assessments embedded in an inquiry-based curriculum. To answer those questions, a randomized experiment was conducted. One thousand and two 6th or 7th graders of 12 teachers in 12 different schools in six states participated in the study. The 12 teachers were matched in pairs and randomly assigned to the experimental and control group. The experimental group employed embedded formative assessments while teaching a science curriculum unit and the control group taught the same unit without formative assessments. All the students were given a motivation survey and one or more achievement tests at pre- and posttest. By comparing the experimental and control students' motivation and achievement scores at pretest and posttest, I examined whether the formative assessment treatment affected students' motivation, learning, and conceptual change. By correlating students' posttest motivation, achievement as well as conceptual change scores, I examined whether students' motivation was related to their achievement and conceptual change. Analyses indicated that, the embedded assessments used by the experimental group did not significantly influence students' motivation, achievement, or conceptual change compared to students in the control group. Most motivation beliefs were correlated with students' achievement in a way similar to what has been reported in the literature. They were not correlated with students' conceptual change scores as hypothesized. Teachers, as well as some contextual factors associated with teachers, were extremely influential on students' motivation, achievement, and conceptual change; teacher effects overshadowed the treatment effect. This study revealed many of the challenges and problems teachers, researchers and randomized experiments are likely to encounter. It also highlighted the difficulty and importance of high-fidelity formative assessment implementation. Finally, it suggested that a cognitive approach in studying conceptual change still has great value to further research.

  9. The Spanish Version of the Unified Protocol for Transdiagnostic Treatment of Emotional Disorders in Adolescents (UP-A) Adapted as a School-Based Anxiety and Depression Prevention Program: Study Protocol for a Cluster Randomized Controlled Trial.

    PubMed

    García-Escalera, Julia; Valiente, Rosa M; Chorot, Paloma; Ehrenreich-May, Jill; Kennedy, Sarah M; Sandín, Bonifacio

    2017-08-21

    Anxiety and depression are common, impairing conditions that evidence high comorbidity rates in adolescence. The Unified Protocol for Transdiagnostic Treatment of Emotional Disorders in Adolescents (UP-A) is one of the few existing resources aimed at applying transdiagnostic treatment principles to target core dysfunctions associated with both anxiety and depression within a single protocol. To our knowledge, this is the first study examining the efficacy of the UP-A adapted as a universal preventive intervention program. The primary aim of this study is to examine whether the Spanish version of the UP-A is more effective than a waitlist (WL) control group in reducing and preventing symptoms of anxiety and depression when employed as a universal, classroom-based preventive intervention. The secondary aim is to investigate changes in a broad range of secondary outcome measures, including negative and positive affect, anxiety sensitivity, emotional avoidance, top problems ratings, school grades, depression and anxiety-related interference, self-esteem, life satisfaction, quality of life, conduct problems, hyperactivity/inattention symptoms, peer problems, prosocial behavior, school adjustment, and discipline problems. Other aims are to assess a range of possible predictors of intervention effects and to examine the feasibility and the acceptability of implementing UP-A in a prevention group format and in a school setting. A cluster, randomized, WL, controlled trial design with classroom as the unit of randomization was used in this study. Five classes including a total of 152 adolescents were randomized to the experimental or WL control groups. Participants in the experimental group received 9 55-minute sessions delivered by advanced doctoral and masters students in clinical psychology. The WL control group will receive the intervention once the 3-month follow-up assessment is completed. We have recruited participants to the cluster randomized controlled trial (RCT) and have conducted the intervention with the experimental group. We expect the WL control group to complete the intervention in July 2017. Data analysis will take place during the second semester of 2017. We expect the experimental group to outperform the WL control group at post-intervention and 3-month follow-up. We also expect the WL control group to show improvements in primary and secondary outcome measures after receiving the intervention. Results will have implications for researchers, families, and education providers. Clinicaltrials.gov NCT03123991; https://clinicaltrials.gov/ct2/show/NCT03123991 (Archived by WebCite at http://www.webcitation.org/6qp7GIzcR). ©Julia García-Escalera, Rosa M Valiente, Paloma Chorot, Jill Ehrenreich-May, Sarah M Kennedy, Bonifacio Sandín. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 21.08.2017.

  10. The Spanish Version of the Unified Protocol for Transdiagnostic Treatment of Emotional Disorders in Adolescents (UP-A) Adapted as a School-Based Anxiety and Depression Prevention Program: Study Protocol for a Cluster Randomized Controlled Trial

    PubMed Central

    García-Escalera, Julia; Valiente, Rosa M; Ehrenreich-May, Jill; Kennedy, Sarah M; Sandín, Bonifacio

    2017-01-01

    Background Anxiety and depression are common, impairing conditions that evidence high comorbidity rates in adolescence. The Unified Protocol for Transdiagnostic Treatment of Emotional Disorders in Adolescents (UP-A) is one of the few existing resources aimed at applying transdiagnostic treatment principles to target core dysfunctions associated with both anxiety and depression within a single protocol. To our knowledge, this is the first study examining the efficacy of the UP-A adapted as a universal preventive intervention program. Objective The primary aim of this study is to examine whether the Spanish version of the UP-A is more effective than a waitlist (WL) control group in reducing and preventing symptoms of anxiety and depression when employed as a universal, classroom-based preventive intervention. The secondary aim is to investigate changes in a broad range of secondary outcome measures, including negative and positive affect, anxiety sensitivity, emotional avoidance, top problems ratings, school grades, depression and anxiety-related interference, self-esteem, life satisfaction, quality of life, conduct problems, hyperactivity/inattention symptoms, peer problems, prosocial behavior, school adjustment, and discipline problems. Other aims are to assess a range of possible predictors of intervention effects and to examine the feasibility and the acceptability of implementing UP-A in a prevention group format and in a school setting. Methods A cluster, randomized, WL, controlled trial design with classroom as the unit of randomization was used in this study. Five classes including a total of 152 adolescents were randomized to the experimental or WL control groups. Participants in the experimental group received 9 55-minute sessions delivered by advanced doctoral and masters students in clinical psychology. The WL control group will receive the intervention once the 3-month follow-up assessment is completed. Results We have recruited participants to the cluster randomized controlled trial (RCT) and have conducted the intervention with the experimental group. We expect the WL control group to complete the intervention in July 2017. Data analysis will take place during the second semester of 2017. Conclusions We expect the experimental group to outperform the WL control group at post-intervention and 3-month follow-up. We also expect the WL control group to show improvements in primary and secondary outcome measures after receiving the intervention. Results will have implications for researchers, families, and education providers. Trial Registration Clinicaltrials.gov NCT03123991; https://clinicaltrials.gov/ct2/show/NCT03123991 (Archived by WebCite at http://www.webcitation.org/6qp7GIzcR) PMID:28827212

  11. Applied statistics in agricultural, biological, and environmental sciences.

    USDA-ARS?s Scientific Manuscript database

    Agronomic research often involves measurement and collection of multiple response variables in an effort to understand the more complex nature of the system being studied. Multivariate statistical methods encompass the simultaneous analysis of all random variables measured on each experimental or s...

  12. Levels of Conformity to Leader in Normal and Critical Situations

    ERIC Educational Resources Information Center

    Gündüz, Yüksel

    2017-01-01

    The aim of this study is to determine primary school, middle school, high school and university students' levels of conformity to leader in normal and critical situations. Experimental model was used in the research. Study group is comprised of 80 students chosen randomly from Karadeniz Bakir Primary School, Gazi Middle School, Kazim Karabekir…

  13. Effective Programs for Elementary Science: A Best-Evidence Synthesis

    ERIC Educational Resources Information Center

    Slavin, Robert E.; Lake, Cynthia; Hanley, Pam; Thurston, Allen

    2012-01-01

    This article presents a systematic review of research on the achievement outcomes of all types of approaches to teaching science in elementary schools. Study inclusion criteria included use of randomized or matched control groups, a study duration of at least 4 weeks, and use of achievement measures independent of the experimental treatment. A…

  14. Can Coloring Mandalas Reduce Anxiety? A Replication Study

    ERIC Educational Resources Information Center

    van der Vennet, Renee; Serice, Susan

    2012-01-01

    This experimental study replicated Curry and Kasser's (2005) research that tested whether coloring a mandala would reduce anxiety. After inducing an anxious mood via a writing activity, participants were randomly assigned to three groups that colored either on a mandala design, on a plaid design, or on a blank paper. Anxiety level was measured…

  15. Assessing Professional Openness to a Novel Publication Approach.

    ERIC Educational Resources Information Center

    DeFiore, Roberta M.; Kramer, Thomas J.

    In response to criticism of the peer review publication process, a study surveyed a random sample of 600 members of the American Psychological Association (APA) to determine (1) whether professional openness exists regarding the publication of a journal highlighting studies that, due to a difficulty in the experimental procedure, would usually be…

  16. Application of Network Planning to Teaching Wind-Surfing

    ERIC Educational Resources Information Center

    Zybko, Przemyslaw; Jaczynowski, Lech

    2008-01-01

    Study aim: To determine the effects of network planning on teaching untrained subjects windsurfing. Material and methods: Untrained physical education students (n = 390), aged 19-23 years, took part in the study while staying on a summer camp. They were randomly assigned into two groups: experimental (n = 216) and control (n = 174). Two methods of…

  17. Flipped Instruction in a High School Science Classroom

    ERIC Educational Resources Information Center

    Leo, Jonathan; Puzio, Kelly

    2016-01-01

    This paper reports on a quasi-experimental study examining the effectiveness of flipped instruction in a 9th grade biology classroom. This study included four sections of freshmen-level biology taught by the first author at a private secondary school in the Pacific Northwest. Using a block randomized design, two sections were flipped and two…

  18. Effects of Activity Based Blended Learning Strategy on Prospective of Teachers' Achievement and Motivation

    ERIC Educational Resources Information Center

    Abdelraheem, Ahmed Yousif; Ahmed, Abdelrahman Mohammed

    2015-01-01

    The study investigates the effect of Activity based Blended Learning strategy and Conventional Blended Learning strategy on students' achievement and motivation. Two groups namely, experimental and control group from Sultan Qaboos University were selected randomly for the study. To assess students' achievement in the different groups, pre- and…

  19. The Effects on Students' Conceptual Understanding of Electric Circuits of Introducing Virtual Manipulatives within a Physical Manipulatives-Oriented Curriculum

    ERIC Educational Resources Information Center

    Zacharia, Zacharias C.; de Jong, Ton

    2014-01-01

    This study investigates whether Virtual Manipulatives (VM) within a Physical Manipulatives (PM)-oriented curriculum affect conceptual understanding of electric circuits and related experimentation processes. A pre-post comparison study randomly assigned 194 undergraduates in an introductory physics course to one of five conditions: three…

  20. An in silico approach helped to identify the best experimental design, population, and outcome for future randomized clinical trials.

    PubMed

    Bajard, Agathe; Chabaud, Sylvie; Cornu, Catherine; Castellan, Anne-Charlotte; Malik, Salma; Kurbatova, Polina; Volpert, Vitaly; Eymard, Nathalie; Kassai, Behrouz; Nony, Patrice

    2016-01-01

    The main objective of our work was to compare different randomized clinical trial (RCT) experimental designs in terms of power, accuracy of the estimation of treatment effect, and number of patients receiving active treatment using in silico simulations. A virtual population of patients was simulated and randomized in potential clinical trials. Treatment effect was modeled using a dose-effect relation for quantitative or qualitative outcomes. Different experimental designs were considered, and performances between designs were compared. One thousand clinical trials were simulated for each design based on an example of modeled disease. According to simulation results, the number of patients needed to reach 80% power was 50 for crossover, 60 for parallel or randomized withdrawal, 65 for drop the loser (DL), and 70 for early escape or play the winner (PW). For a given sample size, each design had its own advantage: low duration (parallel, early escape), high statistical power and precision (crossover), and higher number of patients receiving the active treatment (PW and DL). Our approach can help to identify the best experimental design, population, and outcome for future RCTs. This may be particularly useful for drug development in rare diseases, theragnostic approaches, or personalized medicine. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. The relationship between simulation in nursing education and medication safety.

    PubMed

    Sears, Kimberley; Goldsworthy, Sandra; Goodman, William M

    2010-01-01

    This experimental study examined whether the use of clinical simulation in nursing education could help reduce medication errors. Fifty-four student volunteers were randomly assigned to an experimental (treatment) group (24 students) or a clinical control group (30 students). The treatment replaced some early-term clinical placement hours with a simulated clinical experience. The control group had all normally scheduled clinical hours. Treatment occurred prior to opportunities for medication administration. Copyright 2010, SLACK Incorporated.

  2. Theoretical and experimental studies of hyperreflective polymer-network cholesteric liquid crystal structures with helicity inversion

    NASA Astrophysics Data System (ADS)

    Tasolamprou, A. C.; Mitov, M.; Zografopoulos, D. C.; Kriezis, E. E.

    2009-03-01

    Single-layer cholesteric liquid crystals exhibit a reflection coefficient which is at most 50% for unpolarized incident light. We give theoretical and experimental evidence of single-layer polymer-stabilized cholesteric liquid-crystalline structures that demonstrate hyper-reflective properties. Such original features are derived by the concurrent and randomly interlaced presence of both helicities. The fundamental properties of such structures are revealed by detailed numerical simulations based on a stochastic approach.

  3. Ways of learning: Observational studies versus experiments

    USGS Publications Warehouse

    Shaffer, T.L.; Johnson, D.H.

    2008-01-01

    Manipulative experimentation that features random assignment of treatments, replication, and controls is an effective way to determine causal relationships. Wildlife ecologists, however, often must take a more passive approach to investigating causality. Their observational studies lack one or more of the 3 cornerstones of experimentation: controls, randomization, and replication. Although an observational study can be analyzed similarly to an experiment, one is less certain that the presumed treatment actually caused the observed response. Because the investigator does not actively manipulate the system, the chance that something other than the treatment caused the observed results is increased. We reviewed observational studies and contrasted them with experiments and, to a lesser extent, sample surveys. We identified features that distinguish each method of learning and illustrate or discuss some complications that may arise when analyzing results of observational studies. Findings from observational studies are prone to bias. Investigators can reduce the chance of reaching erroneous conclusions by formulating a priori hypotheses that can be pursued multiple ways and by evaluating the sensitivity of study conclusions to biases of various magnitudes. In the end, however, professional judgment that considers all available evidence is necessary to render a decision regarding causality based on observational studies.

  4. Randomized controlled trial of care bundles with chlorhexidine dressing and advanced dressings to prevent catheter-related bloodstream infections in pediatric hematology-oncology patients.

    PubMed

    Gerçeker, Gülçin Özalp; Yardımcı, Figen; Aydınok, Yeşim

    2017-06-01

    To compare the effects of the care bundles including chlorhexidine dressing and advanced dressings on the catheter-related bloodstream infection (CRBSI) rates in pediatric hematology-oncology patients with central venous catheters (CVCs). Twenty-seven PHO patients were recruited to participate in a prospective, randomized study in Turkey. The researcher used care bundles with chlorhexidine dressing in the experimental group (n = 14), and care bundles with advanced dressings in the control group (n = 13). According to the study results, 28.6% of the patients in the experimental group had CRBSI, while this rate was 38.5% in the control group patients. The CRBSI rate in the experimental group was 3.9, and the control group had 4.4 per 1000 inpatient catheter days. There was no exit-site infection in the experimental group. However, the control group had 1.7 per 1000 inpatient catheter days. Even though there was no difference between the two groups in which the researcher implemented care bundles with chlorhexidine dressing and advanced dressings in terms of CRBSI development, there was reduction in the CRBSI rates thanks to the care bundle approach. It is possible to control the CRBSI rates using care bundles in pediatric hematology-oncology patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Effects of a Stretching Development and Maintenance Program on Hamstring Extensibility in Schoolchildren: A Cluster-Randomized Controlled Trial

    PubMed Central

    Mayorga-Vega, Daniel; Merino-Marban, Rafael; Manzano-Lagunas, Jorge; Blanco, Humberto; Viciana, Jesús

    2016-01-01

    The main purpose of the present study was to examine the effects of a physical education-based stretching development and maintenance program on hamstring extensibility in schoolchildren. A sample of 150 schoolchildren aged 7-10 years old from a primary school participated in the present study (140 participants were finally included). The six classes balanced by grade were cluster randomly assigned to the experimental group 1 (n = 51), experimental group 2 (n = 51) or control group (n = 49) (i.e., a cluster randomized controlled trial design was used). During the physical education classes, the students from the experimental groups 1 and 2 performed a four-minute stretching program twice a week for nine weeks (first semester). Then, after a five-week period of detraining coinciding with the Christmas holidays, the students from the experimental groups 1 and 2 completed another stretching program twice a week for eleven weeks (second semester). The students from the experimental group 1 continued performing the stretching program for four minutes while those from the experimental group 2 completed a flexibility maintenance program for only one minute. The results of the two-way analysis of variance showed that the physical education-based stretching development program significantly improved the students’ hamstring extensibility (p < 0.001), as well as that these gains obtained remained after the stretching maintenance program (p < 0.001). Additionally, statistically significant differences between the two experimental groups were not found (p > 0.05). After a short-term stretching development program, a physical education-based stretching maintenance program of only one-minute sessions twice a week is effective in maintaining hamstring extensibility among schoolchildren. This knowledge could help and guide teachers to design programs that allow a feasible and effective development and maintenance of students’ flexibility in the physical education setting. Key points A physical education-based stretching maintenance program of only one-minute sessions twice a week is effective in maintaining hamstring extensibility among schoolchildren. A four-minute maintenance program shows similar effects that the one-minute maintenance program on hamstring extensibility among schoolchildren. Physical education teachers and other practitioners could carry out one-minute programs for a feasible and effective maintenance of students’ flexibility. PMID:26957928

  6. Two biomarker-directed randomized trials in European and Chinese patients with nonsmall-cell lung cancer: the BRCA1-RAP80 Expression Customization (BREC) studies.

    PubMed

    Moran, T; Wei, J; Cobo, M; Qian, X; Domine, M; Zou, Z; Bover, I; Wang, L; Provencio, M; Yu, L; Chaib, I; You, C; Massuti, B; Song, Y; Vergnenegre, A; Lu, H; Lopez-Vivanco, G; Hu, W; Robinet, G; Yan, J; Insa, A; Xu, X; Majem, M; Chen, X; de Las Peñas, R; Karachaliou, N; Sala, M A; Wu, Q; Isla, D; Zhou, Y; Baize, N; Zhang, F; Garde, J; Germonpre, P; Rauh, S; ALHusaini, H; Sanchez-Ronco, M; Drozdowskyj, A; Sanchez, J J; Camps, C; Liu, B; Rosell, R

    2014-11-01

    In a Spanish Lung Cancer Group (SLCG) phase II trial, the combination of BRCA1 and receptor-associated protein 80 (RAP80) expression was significantly associated with outcome in Caucasian patients with nonsmall-cell lung cancer (NSCLC). The SLCG therefore undertook an industry-independent collaborative randomized phase III trial comparing nonselected cisplatin-based chemotherapy with therapy customized according to BRCA1/RAP80 expression. An analogous randomized phase II trial was carried out in China under the auspices of the SLCG to evaluate the effect of BRCA1/RAP80 expression in Asian patients. Eligibility criteria included stage IIIB-IV NSCLC and sufficient tumor specimen for molecular analysis. Randomization to the control or experimental arm was 1 : 1 in the SLCG trial and 1 : 3 in the Chinese trial. In both trials, patients in the control arm received docetaxel/cisplatin; in the experimental arm, patients with low RAP80 expression received gemcitabine/cisplatin, those with intermediate/high RAP80 expression and low/intermediate BRCA1 expression received docetaxel/cisplatin, and those with intermediate/high RAP80 expression and high BRCA1 expression received docetaxel alone. The primary end point was progression-free survival (PFS). Two hundred and seventy-nine patients in the SLCG trial and 124 in the Chinese trial were assessable for PFS. PFS in the control and experimental arms in the SLCG trial was 5.49 and 4.38 months, respectively [log rank P = 0.07; hazard ratio (HR) 1.28; P = 0.03]. In the Chinese trial, PFS was 4.74 and 3.78 months, respectively (log rank P = 0.82; HR 0.95; P = 0.82). Accrual was prematurely closed on the SLCG trial due to the absence of clinical benefit in the experimental over the control arm. However, the BREC studies provide proof of concept that an international, nonindustry, biomarker-directed trial is feasible. Thanks to the groundwork laid by these studies, we expect that ongoing further research on alternative biomarkers to elucidate DNA repair mechanisms will help define novel therapeutic approaches. NCT00617656/GECP-BREC and ChiCTR-TRC-12001860/BREC-CHINA. © The Author 2014. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  7. The Lévy flight paradigm: random search patterns and mechanisms.

    PubMed

    Reynolds, A M; Rhodes, C J

    2009-04-01

    Over recent years there has been an accumulation of evidence from a variety of experimental, theoretical, and field studies that many organisms use a movement strategy approximated by Lévy flights when they are searching for resources. Lévy flights are random movements that can maximize the efficiency of resource searches in uncertain environments. This is a highly significant finding because it suggests that Lévy flights provide a rigorous mathematical basis for separating out evolved, innate behaviors from environmental influences. We discuss recent developments in random-search theory, as well as the many different experimental and data collection initiatives that have investigated search strategies. Methods for trajectory construction and robust data analysis procedures are presented. The key to prediction and understanding does, however, lie in the elucidation of mechanisms underlying the observed patterns. We discuss candidate neurological, olfactory, and learning mechanisms for the emergence of Lévy flight patterns in some organisms, and note that convergence of behaviors along such different evolutionary pathways is not surprising given the energetic efficiencies that Lévy flight movement patterns confer.

  8. The Effect of Emotional Focused Intervention on Spousal Emotional Abuse and Marital Satisfaction among Elderly Married Couples: A Randomized Controlled Trial.

    PubMed

    Hazrati, Maryam; Hamid, Tengku Aizan; Ibrahim, Rahimah; Hassan, Siti Aishah; Sharif, Farkhondeh; Bagheri, Zahra

    2017-10-01

    This study examined the impacts of an Emotional Focused Intervention on emotional abuse behaviors and marital satisfaction among the elderly married couples. This randomized controlled trial study was carried out in Shiraz-Iran, during September 2013-2014. The elderly couples were invited to join an emotional focused intervention, following the advertisement and announcement on bulletin boards in the elderly day clinic centers and all governmental primary health care centers. Then, 57 couples (114 participants) who were eligible for study were assigned in two groups by block randomization (29 in the experimental and 28 in the control group(.The couples in the experimental group received intervention twice a week for four weeks. Each session lasted 90 minutes. The control group didn't receive any intervention and the subjects were put in the waiting list. The outcome measures were evaluated by Multidimensional Measure of Emotional Abuse Questionnaire (MMEAQ) and Marital Satisfaction Questionnaire for Older People (MSQFOP). Repeated measurement ANOVA was used to detect any significant changes between groups in their mean scores of emotional abuse behaviors and marital satisfaction from pre- to post-test, and 3 months after the intervention. Analysis of data was performed using SPSS, version 19, and P≤0.05 was measured as significant. The mean duration of marriage was 39.56±9.64 years. In the experimental group, the abusive behaviors decreased significantly (P<0.001) at times 2 and 3 compared with time 1, and marital satisfaction improved significantly only at time 3 (P<0.001). These differences were not significant in the control group. Emotion-focused couple-based interventions are helpful in reducing the spousal emotional abuse and improving marital satisfaction in among the elderly couples. Trial Registration Number: 2013111715426N1.

  9. Effects of a T'ai Chi-Based Health Promotion Program on Metabolic Syndrome Markers, Health Behaviors, and Quality of Life in Middle-Aged Male Office Workers: A Randomized Trial.

    PubMed

    Choi, Ye-Sook; Song, Rhayun; Ku, Bon Jeong

    2017-12-01

    To determine the effects of a t'ai chi-applied worksite health promotion program on metabolic syndrome markers, health behaviors, and quality of life in middle-aged male office workers at a high risk of metabolic syndrome. A prospective randomized controlled study. Health center of a government office building in Korea. Forty-three male office workers with two or more metabolic syndrome markers. The office workers were randomly assigned either to an experimental group that received t'ai chi combined with health education twice weekly for 12 weeks, or to a control group that received health education only. Blood sampling for metabolic syndrome markers and structured questionnaires for health behaviors and quality of life. The experimental group showed significant reductions in systolic (t = -3.103, p = 0.003) and diastolic (t = -2.159, p = 0.037) blood pressures and the triglyceride level (t = -2.451, p = 0.019) compared with the control group. Those in the experimental group also performed health behaviors more frequently (t = 4.047, p < 0.001) and reported a significantly better quality of life (t = 3.193, p = 0.003) than those in the control group. The study findings show that t'ai chi was an effective adjunctive intervention in a worksite health promotion program for middle-aged office workers at a high risk of metabolic syndrome. Future studies should examine the long-term effects of t'ai chi-applied worksite health promotion programs in individuals with confirmed metabolic syndrome.

  10. Opportunistic detection of atrial fibrillation in subjects aged 65 years or older in primare care: a randomised clinical trial of efficacy. DOFA-AP study protocol.

    PubMed

    Pérula-de-Torres, Luis Á; Martínez-Adell, Miguel Á; González-Blanco, Virginia; Baena-Díez, José M; Martín-Rioboó, Enrique; Parras-Rejano, Juan M; González-Lama, Jesús; Martín-Alvarez, Remedios; Ruiz-Moral, Roger; Fernández-García, José Á; Pérez-Díaz, Modesto; Ruiz-de-Castroviejo, Joaquin; Pérula-de-Torres, Carlos; Valero-Martín, Antonio; Roldán-Villalobos, Ana; Criado-Larumbe, Margarita; Burdoy-Joaquín, Emili; Coma-Solé, Montserrat; Cervera-León, Mercè; Cuixart-Costa, Lluís

    2012-10-30

    Clinical Practice Guidelines recommend using peripheral blood pulse measuring as a screening test for Atrial Fibrillation. However, there is no adequate evidence supporting the efficacy of such procedure in primary care clinical practice. This paper describes a study protocol designed to verify whether early opportunistic screening for Atrial Fibrillation by measuring blood pulse is more effective than regular practice in subjects aged 65 years attending primary care centers. An cluster-randomized controlled trial conducted in Primary Care Centers of the Spanish National Health Service. A total of 269 physicians and nurses will be allocated to one of the two arms of the trial by stratified randomization with a 3:2 ratio (three practitioners will be assigned to the Control Group for every two practitioners assigned to the Experimental Group). As many as 12 870 patients aged 65 years or older and meeting eligibility criteria will be recruited (8 580 will be allocated to the Experimental Group and 4 290 to the Control Group). Randomization and allocation to trial groups will be carried out by a central computer system. The Experimental Group practitioners will conduct an opportunistic case finding for patients with Atrial Fibrillation, while the Control Group practitioners will follow the regular guidelines. The first step will be finding new Atrial Fibrillation cases. A descriptive inferential analysis will be performed (bivariate and multivariate by multilevel logistic regression analysis). If our hypothesis is confirmed, we expect Primary Care professionals to take a more proactive approach and adopt a new protocol when a patient meeting the established screening criteria is identified. Finally, we expect this measure to be incorporated into Clinical Practice Guidelines. The study is registered as NCT01291953 (ClinicalTrials.gob).

  11. A Prospective Randomized Clinical Trial of a Novel, Noninvasive Perfusion Enhancement System for the Prevention of Hospital-Acquired Sacral Pressure Injuries.

    PubMed

    Bharucha, Jitendra B; Seaman, Linda; Powers, Michele; Kelly, Erica; Seaman, Rodney; Forcier, Lea; McGinnis, Janice; Nodiff, Isabel; Pawlak, Brooke; Snyder, Samantha; Nodiff, Susan; Patel, Rohan; Squitieri, Rafael; Wang, Lansheng

    2018-06-08

    The purpose of this study was to determine the effectiveness of a novel, noninvasive perfusion enhancement system versus beds with integrated alternating pressure capabilities for the prevention of hospital-acquired sacral region (sacral, coccygeal, and ischium) pressure injuries in a high-risk, acute care patient population. A prospective randomized trial of high-risk inpatients without preexisting sacral region pressure injuries was conducted. The sample comprised 431 randomly enrolled adult patients in a 300-bed tertiary care community teaching hospital. Subjects were randomly allocated to one of 2 groups: control and experimental. Both groups received "standard-of-care" pressure injury prevention measures per hospital policy, and both were placed on alternating pressure beds during their hospital stays. In addition, patients in the experimental group used a noninvasive perfusion enhancement system placed on top of their alternating pressure beds and recovery chairs throughout their hospital stay. Fischer's exact probability test was used to compare group differences, and odds ratio (OR) were calculated for comparing pressure injury rates in the experimental and control groups. Three hundred ninety-nine patients completed the trial; 186 patients were allocated to the experimental group and 213 patients to the control group. Eleven patients in the control group versus 2 in the experimental group developed hospital-acquired sacral region pressure injuries (51.6% vs 1.07%; P = .024). Control patients were 5.04 times more likely to develop hospital-acquired sacral region pressure injuries (OR = 0.1996; 95% CI, 0.0437-0.9125). Patients using a noninvasive perfusion enhancement system developed significantly fewer hospital-acquired sacral pressure injuries than those using an alternating pressure bed without the perfusion enhancement system. These findings suggest that a perfusion enhancement system enhances the success of use of pressure redistributing beds for prevention of hospital-acquired sacral pressure injuries.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

  12. An alcohol training program improves Chinese nurses' knowledge, self-efficacy, and practice: a randomized controlled trial.

    PubMed

    Tsai, Yun-Fang; Tsai, Mei-Chu; Lin, Yea-Pyng; Weng, Chih-Erh; Chou, Yu-Ling; Chen, Ching-Yen

    2011-05-01

    Excessive alcohol use has been associated with health, social and legal problems. Helping health care providers to manage hazardous or harmful drinkers is an important worldwide issue. Alcohol is a legal and accessible substance in Taiwan and is viewed as an acceptable drink for relieving stress and enhancing socialization in Chinese culture. These cultural factors may contribute to drinking problems being easily ignored and to lack of alcohol training programs for health care providers. For this randomized controlled clinical trial with 1- and 3-month posttests, six hospitals were randomly selected throughout Taiwan and were randomly assigned to an experimental or control group. In these hospitals, nurses were selected from the Emergency Department, psychiatric, and gastrointestinal medical-surgical units where most patients with alcohol problems are seen. For the experimental group, nurses received a 1.5-hour alcohol training program consisting of an introduction to alcohol, factors influencing alcohol drinking, impacts of high-risk drinking on a person, as well as introduction to and practice of the Alcohol Use Disorders Identification Test and brief alcohol intervention. The program also discussed Taiwanese nurses' perceived barriers and facilitators to intervening for problem alcohol use. Teaching strategies included lecture, discussion, demonstration, practice, role-playing, and sharing experiences. The control group did not receive any training. Data were collected at pretest, 1-month, and 3-month posttests using a self-report questionnaire on knowledge, self-efficacy, clinical practice scales, and a demographic form. The study was completed by 395 nurses, including 191 nurses in the experimental group and 204 nurses in the control group. Knowledge scores significantly improved in the experimental group at the 1- and 3-month posttests but not for the control group. Similarly, nurses' self-efficacy and clinical practice scores significantly improved in the experimental group at the 3-month posttest but not for the control group. Our results suggest that the alcohol training program could be used to enhance nurses' alcohol knowledge, self-efficacy, and clinical practice not only in Taiwan but also other countries. Copyright © 2011 by the Research Society on Alcoholism.

  13. Effectiveness of Computer Tailoring Versus Peer Support Web-Based Interventions in Promoting Physical Activity Among Insufficiently Active Canadian Adults With Type 2 Diabetes: Protocol for a Randomized Controlled Trial

    PubMed Central

    Côté, José

    2016-01-01

    Background Type 2 diabetes is a major challenge for Canadian public health authorities, and regular physical activity is a key factor in the management of this disease. Given that less than half of people with type 2 diabetes in Canada are sufficiently active to meet the Canadian Diabetes Association's guidelines, effective programs targeting the adoption of regular physical activity are in demand for this population. Many researchers have argued that Web-based interventions targeting physical activity are a promising avenue for insufficiently active populations; however, it remains unclear if this type of intervention is effective among people with type 2 diabetes. Objective This research project aims to evaluate the effectiveness of two Web-based interventions targeting the adoption of regular aerobic physical activity among insufficiently active adult Canadian Francophones with type 2 diabetes. Methods A 3-arm, parallel randomized controlled trial with 2 experimental groups and 1 control group was conducted in the province of Quebec, Canada. A total of 234 participants were randomized at a 1:1:1 ratio to receive an 8-week, fully automated, computer-tailored, Web-based intervention (experimental group 1); an 8-week peer support (ie, Facebook group) Web-based intervention (experimental group 2); or no intervention (control group) during the study period. Results The primary outcome of this study is self-reported physical activity level (total min/week of moderate-intensity aerobic physical activity). Secondary outcomes are attitude, social influence, self-efficacy, type of motivation, and intention. All outcomes are assessed at baseline and 3 and 9 months after baseline with a self-reported questionnaire filled directly on the study websites. Conclusions By evaluating and comparing the effectiveness of 2 Web-based interventions characterized by different behavior change perspectives, findings of this study will contribute to advances in the field of physical activity promotion in adult populations with type 2 diabetes. Trial Registration International Standard Randomized Controlled Trial Number (ISRCTN): ISRCTN15747108; http://www.isrctn.com/ISRCTN15747108 (Archived by WebCite at http://www.webcitation.org/6eJTi0m3r) PMID:26869015

  14. Effects of a Skin Barrier Cream on Management of Incontinence-Associated Dermatitis in Older Women: A Cluster Randomized Controlled Trial.

    PubMed

    Kon, Yuka; Ichikawa-Shigeta, Yoshie; Iuchi, Terumi; Nakajima, Yukari; Nakagami, Gojiro; Tabata, Keiko; Sanada, Hiromi; Sugama, Junko

    The purpose of this study was to examine the effects of a skin barrier cream with moisturization and skin-protectant characteristics for improving the severity of incontinence-associated dermatitis (IAD) pertaining to the skin physiology and appearance. We measured the following outcomes: (1) skin physiological characteristics indicating skin protection and enhancement of the skin's moisture barrier (stratum corneum hydration, dermis hydration level, transepidermal water loss, and skin pH); and (2) changes in skin appearance (the degree of erythema and pigmentation, and the sulcus cutis condition). Single-blind, cluster randomized controlled trial. The study was conducted in a long-term care facility in Japan between November 7, 2011, and May 6, 2012. We used block randomization to obtain a random sample of 6 (4 experimental and 2 control) out of 10 available wards. All subjects were elderly women with IAD of the buttock or inner thigh. We assessed 295 patients, but only 33 met inclusion criteria; 18 were allocated to the experimental group and 15 were allocated to the control group. All participants were managed with cleansing with a skin cleanser and application of a moisturizer daily. In addition, a skin barrier cream designed to enhance the skin's moisture barrier and act as a protective barrier was applied to the skin of patients in the experimental group 3 times a day when absorptive briefs were changed. Skin physiological and appearance characteristics were scored only at the buttock or thigh area. All data were collected on days 1 and 14 of the study. Univariate analysis found that the erythema index was lower in the intervention group than in the control group at day 14 (P = .004). Multivariate analysis found significant associations between use of the skin barrier cream and increased stratum corneum hydration (β= .443, P = .031), decreased skin pH (β=-.439, P = .020), and magnitude of erythema (β=-.451, P = .018). Study findings suggest that a barrier cream designed to enhance the skin's moisture barrier and act as a skin protectant increased stratum corneum hydration, reduced cutaneous pH, and reduced erythema.

  15. The effect of integrating constructivist and evidence-based practice on baccalaureate nursing student's cognitive load and learning performance in a research course.

    PubMed

    Hsieh, Suh-Ing; Hsu, Li-Ling; Huang, Tzu-Hsin

    2016-07-01

    Baccalaureate nursing students perceive research as unattractive, doubt the value of nursing research, and do not appreciate the link of research with practice. No studies have examined students' cognitive load during an evidence-based practice research course versus a traditional research course. To assess the effect of integrating constructivist theories and evidence-based practice on student cognitive load and learning performance in a research course. A true experimental study. A Registered Nurse-to-Bachelor of Science in Nursing program. Six classes of second-year students. Students were randomly allocated to the control group (two classes) or the experimental group (two classes) using cluster randomization. The control group underwent "traditional research"; the experimental group experienced "integrating evidence-based practice into research." Instruments for outcome assessment include the Cognitive Load Scale, cognitive test, team critique paper, and qualitative feedback on course satisfaction. The between-subjects effects were compared by Analysis of Covariance. The experimental group had significantly higher mental load (8.74 vs. 7.27, p<.001), mental effort (11.07 vs. 10.07, p=.009), mental efficiency (0.33 vs. -0.31, p<.001), and research knowledge (70.61 vs. 44.92, p<.001) than the control group. The experimental group had better critique paper scores in introduction (92.80%), literature review (91.70%), and assignment requirement and writing (89.40%). Some experimental learners expressed satisfaction with learning evidence-based practice (17.78%) and critiquing a research article (7.78%). Integrating evidence-based practice into a research course not only improved the research knowledge of baccalaureate nursing students, but also increased their mental load, mental effort, and mental efficiency. Additional studies may track learners' responses to different learning systems using the developed instrument to measure the three types of cognitive load. These findings may help educators design more effective and interesting curricula for integrating research and evidence-based practice into the studies of student nurses. Copyright © 2016. Published by Elsevier Ltd.

  16. Political science. Reverse-engineering censorship in China: randomized experimentation and participant observation.

    PubMed

    King, Gary; Pan, Jennifer; Roberts, Margaret E

    2014-08-22

    Existing research on the extensive Chinese censorship organization uses observational methods with well-known limitations. We conducted the first large-scale experimental study of censorship by creating accounts on numerous social media sites, randomly submitting different texts, and observing from a worldwide network of computers which texts were censored and which were not. We also supplemented interviews with confidential sources by creating our own social media site, contracting with Chinese firms to install the same censoring technologies as existing sites, and--with their software, documentation, and even customer support--reverse-engineering how it all works. Our results offer rigorous support for the recent hypothesis that criticisms of the state, its leaders, and their policies are published, whereas posts about real-world events with collective action potential are censored. Copyright © 2014, American Association for the Advancement of Science.

  17. The effects of Internet or interactive computer-based patient education in the field of breast cancer: a systematic literature review.

    PubMed

    Ryhänen, Anne M; Siekkinen, Mervi; Rankinen, Sirkku; Korvenranta, Heikki; Leino-Kilpi, Helena

    2010-04-01

    The aim of this systematic review was to analyze what kind of Internet or interactive computer-based patient education programs have been developed and to analyze the effectiveness of these programs in the field of breast cancer patient education. Patient education for breast cancer patients is an important intervention to empower the patient. However, we know very little about the effects and potential of Internet-based patient education in the empowerment of breast cancer patients. Complete databases were searched covering the period from the beginning of each database to November 2008. Studies were included if they concerned patient education for breast cancer patients with Internet or interactive computer programs and were based on randomized controlled, on clinical trials or quasi-experimental studies. We identified 14 articles involving 2374 participants. The design was randomized controlled trial in nine papers, in two papers clinical trial and in three quasi-experimental. Seven of the studies were randomized to experimental and control groups, in two papers participants were grouped by ethnic and racial differences and by mode of Internet use and three studies measured the same group pre- and post-tests after using a computer program. The interventions used were described as interactive computer or multimedia programs and use of the Internet. The methodological solutions of the studies varied. The effects of the studies were diverse except for knowledge-related issues. Internet or interactive computer-based patient education programs in the care of breast cancer patients may have positive effect increasing breast cancer knowledge. The results suggest a positive relationship between the Internet or computer-based patient education program use and the knowledge level of patients with breast cancer but a diverse relationship between patient's participation and other outcome measures. There is need to develop and research more Internet-based patient education. 2009 Elsevier Ireland Ltd. All rights reserved.

  18. Screening and brief interventions for hazardous and harmful alcohol use among university students in South Africa: results from a randomized controlled trial.

    PubMed

    Pengpid, Supa; Peltzer, Karl; van der Heever, Hendry; Skaal, Linda

    2013-05-21

    The aim of this study was to assess the effectiveness of Screening and Brief Intervention (SBI) for alcohol problems among university students in South Africa. The study design for this efficacy study is a randomized controlled trial with 6- and 12-month follow-ups to examine the effects of a brief alcohol intervention to reduce alcohol use by hazardous and harmful drinkers in a university setting. The unit of randomization is the individual university student identified as a hazardous or harmful drinker attending public recruitment venues in a university campus. University students were screened for alcohol problems, and those identified as hazardous or harmful drinkers were randomized into an experimental or control group. The experimental group received one brief counseling session on alcohol risk reduction, while the control group received a health education leaflet. Results indicate that of the 722 screened for alcohol and who agreed to participate in the trial 152 (21.1%) tested positive for the Alcohol Use Disorder Identification Test (AUDIT) (score 8 or more). Among the 147 (96.7%) university students who also attended the 12-month follow-up session, the intervention effect on the AUDIT score was -1.5, which was statistically significant (P = 0.009). Further, the depression scores marginally significantly decreased over time across treatment groups, while other substance use (tobacco and cannabis use), self-rated health status and Posttraumatic Stress Disorder (PTSD) scores did not change over time across treatment groups. The study provides evidence of effective brief intervention by assistant nurses with hazardous and harmful drinkers in a university setting in South Africa. The short duration of the brief intervention makes it a realistic candidate for use in a university setting.

  19. Construction of a stochastic model of track geometry irregularities and validation through experimental measurements of dynamic loading

    NASA Astrophysics Data System (ADS)

    Panunzio, Alfonso M.; Puel, G.; Cottereau, R.; Simon, S.; Quost, X.

    2017-03-01

    This paper describes the construction of a stochastic model of urban railway track geometry irregularities, based on experimental data. The considered irregularities are track gauge, superelevation, horizontal and vertical curvatures. They are modelled as random fields whose statistical properties are extracted from a large set of on-track measurements of the geometry of an urban railway network. About 300-1000 terms are used in the Karhunen-Loève/Polynomial Chaos expansions to represent the random fields with appropriate accuracy. The construction of the random fields is then validated by comparing on-track measurements of the contact forces and numerical dynamics simulations for different operational conditions (train velocity and car load) and horizontal layouts (alignment, curve). The dynamics simulations are performed both with and without randomly generated geometrical irregularities for the track. The power spectrum densities obtained from the dynamics simulations with the model of geometrical irregularities compare extremely well with those obtained from the experimental contact forces. Without irregularities, the spectrum is 10-50 dB too low.

  20. Unitary n -designs via random quenches in atomic Hubbard and spin models: Application to the measurement of Rényi entropies

    NASA Astrophysics Data System (ADS)

    Vermersch, B.; Elben, A.; Dalmonte, M.; Cirac, J. I.; Zoller, P.

    2018-02-01

    We present a general framework for the generation of random unitaries based on random quenches in atomic Hubbard and spin models, forming approximate unitary n -designs, and their application to the measurement of Rényi entropies. We generalize our protocol presented in Elben et al. [Phys. Rev. Lett. 120, 050406 (2018), 10.1103/PhysRevLett.120.050406] to a broad class of atomic and spin-lattice models. We further present an in-depth numerical and analytical study of experimental imperfections, including the effect of decoherence and statistical errors, and discuss connections of our approach with many-body quantum chaos.

  1. Leader Positivity and Follower Creativity: An Experimental Analysis

    ERIC Educational Resources Information Center

    Avey, James B.; Richmond, F. Lynn; Nixon, Don R.

    2012-01-01

    Using an experimental research design, 191 working adults were randomly assigned to two experimental conditions in order to test a theoretical model linking leader and follower positive psychological capital (PsyCap). Multiple methods were used to gather information from the participants. We found when leader PsyCap was manipulated experimentally,…

  2. Efficacy of an Attachment-Based Intervention Model on Health Indices in Children with Chronic Disease and Their Mothers.

    PubMed

    Dehghani-Arani, Fateme; Besharat, Mohammad Ali; Fitton, Victoria A; Aghamohammadi, Asghar

    2018-05-07

    Studies have shown significant relationship between health conditions and attachment. This study aimed to examine an attachment-based intervention model named mother-child-disease triangle (MCDT) on health indices in children with chronic disease and their mothers. This randomized trial study included 22 volunteer children aged 12-18 years undergoing medical treatment for a chronic disease and their mothers. After evaluation by 28-form General Health Questionnaire (GHQ-28), inventory of parent and peer attachment (IPPA), 28-form Child Health Questionnaire (CHQ-28) and Illness Perception Questionnaire (IPQ), the mother-child dyads were paired on the basis of IPPA scores. These pairs were then randomly assigned to an experimental or control group. The experimental group received ten 90-min sessions of MCDT over a 7-week period. Meanwhile, the control group received ten simple conversational sessions as a dummy intervention. In accordance with this study's pre-test/post-test design, both groups were evaluated once again after completing their respective treatment. Multivariate analysis of covariance (MANCOVA) showed members of the experimental group to have significantly stronger attachment and better physiological and psychosocial health than those in the control group. These findings suggest that attachment-based interventions can be used to improve the effectiveness of treatment among children with chronic disease and their mothers.

  3. Game-Based Virtual Reality Canoe Paddling Training to Improve Postural Balance and Upper Extremity Function: A Preliminary Randomized Controlled Study of 30 Patients with Subacute Stroke.

    PubMed

    Lee, Myung Mo; Lee, Kyeong Jin; Song, Chang Ho

    2018-04-27

    BACKGROUND Virtual reality (VR) training with motion-controlled console games can be incorporated into stroke rehabilitation programs. The use of a variety of gaming software can provide the patient with an opportunity to perform activities that are exciting, entertaining, and that may not be feasible in clinical environments. The aim of this preliminary randomized controlled study was to investigate the effects of game-based VR canoe paddling training, when combined with conventional physical rehabilitation programs, on postural balance and upper extremity function in 30 patients with subacute stroke. MATERIAL AND METHODS Thirty patients, who were within six months following the diagnosis of stroke, were randomly allocated to either the experimental group (n=15) or the control group (n=15). All participants participated in a conventional rehabilitation program. Also, the experimental group (n=15) performed the VR canoe paddling training for 30 minutes each day, three times per week, for five weeks. After five weeks, outcomes of changes in postural balance and upper extremity function were evaluated and compared between the two groups. RESULTS At five weeks, postural balance and upper extremity function showed significant improvements in both patients groups when compared with the baseline measurements (p<0.05). However, postural balance and upper extremity function were significantly improved in the experimental group when compared with the control group (p<0.05). CONCLUSIONS Game-based VR canoe paddling training is an effective rehabilitation therapy that enhances postural balance and upper extremity function in patients with subacute stroke when combined with conventional physical rehabilitation programs.

  4. [Effects of an exercise and relaxation aquatic program in patients with spondyloarthritis: A randomized trial].

    PubMed

    Fernández García, Rubén; Sánchez Sánchez, Laura de Carmen; López Rodríguez, María Del Mar; Sánchez Granados, Gema

    2015-11-06

    Spondyloarthritis is a general term referring to a group of chronic rheumatic illnesses that share clinical, genetic, radiological and epidemiological features. The clinical presentation of spondyloarthritis is characterized by the compromise of both the axial and peripheral articular skeleton. We aimed to evaluate the efficacy of an aquatic exercise plus relaxation program in patients with spondyloarthritis. This was a randomized single blind study including 30 patients with spondylitis who were randomly assigned to an experimental or control group. For 2 months, the experimental group underwent an aquatic fitness plus relaxation program (3 sessions per week). Evaluations were also performed in the control group the same days as the experimental group but they did not participate in any supervised exercise program. The following data were obtained at baseline and immediately after application of the last session: Bath Ankylosing Spondylitis Functional Index, Bath Ankylosing Spondylitis Disease Activity Index, Health Questionnaire SF-12 and Sigma PC3(®) (Sigma-Elektro GmbH, Neustadt, Germany) Heart Rate Monitor. The Mann-Whitney test showed statistically significant differences in the quality of life (physical function [P=.05]), Bath Ankylosing Spondylitis Functional Index (P=.015), Bath Ankylosing Spondylitis Disease Activity Index (fatigue [P=.032], neck pain, back and hips [P=.045], pain or swelling in other joints [P=.032] and in waking morning stiffness [P=.019]). The results of the present study suggest that therapy with physical exercise plus relaxation provides benefits to spondyloarthritis patients and these are advised as a part of their usual treatment. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  5. The Effect of Music on Anxiety and Cardiovascular Indices in Patients Undergoing Coronary Artery Bypass Graft: A Randomized Controlled Trial

    PubMed Central

    Heidari, Saeide; Babaii, Atye; Abbasinia, Mohammad; Shamali, Mahdi; Abbasi, Mohammad; Rezaei, Mahboobe

    2015-01-01

    Background: The instability of cardiovascular indices and anxiety disorders are common among patients undergoing coronary artery bypass graft (CABG) and could interfere with their recovery. Therefore, improving the cardiovascular indices and anxiety is essential. Objectives: This study aimed to investigate the effect of music therapy on anxiety and cardiovascular indices in patients undergoing CABG. Patients and Methods: In this randomized controlled trial, 60 patients hospitalized in the cardiovascular surgical intensive care unit of Shahid Beheshti Hospital in Qom city, Iran, in 2013 were selected using a consecutive sampling method and randomly allocated into the experimental and control groups. In the experimental group, patients received 30 minutes of light music, whereas in the control group, patients had 30 minutes of rest in bed. The cardiovascular indices and anxiety were measured immediately before, immediately after and half an hour after the study. Data were analyzed using the chi-square test and repeated measures analysis of variance. Results: Compared to the immediately before intervention, the mean anxiety scores immediately after and 30 minutes after the intervention were significantly lower in the experimental group (P < 0.037) while it did not significantly change in the control group. However, there were no significant differences regarding the cardiovascular indices in the three consecutive measurements (P > 0.05). Conclusions: Music therapy is effective in decreasing anxiety among patients undergoing CABG. However, the intervention was not effective on cardiovascular indices. Music can effectively be used as a non-pharmacological method to manage anxiety after CABG. PMID:26835471

  6. Immediate effect of subliminal priming with positive reward stimuli on standing balance in healthy individuals: A randomized controlled trial.

    PubMed

    Aoyama, Yasuhiro; Uchida, Hiroyuki; Sugi, Yasuyuki; Kawakami, Akinobu; Fujii, Miki; Kiso, Kanae; Kono, Ryota; Takebayashi, Takashi; Hirao, Kazuki

    2017-07-01

    Information received subconsciously can influence exercise performance; however, it remains unclear whether subliminal or supraliminal reward is more effective in improving standing balance ability when priming stimuli are subconsciously delivered. The present study aimed to compare the effects of subliminal priming-plus-subliminal reward stimuli (experimental) with subliminal priming-plus-supraliminal reward stimuli (control) on standing balance ability. This was a single-blind (outcome assessor), parallel-group, randomized controlled trial involving healthy young adults recruited from a university in Japan. Assessments were conducted at baseline and immediately after intervention. The primary outcome was the functional reach test (FRT) measurement. The secondary outcome was one-leg standing time (OLST) with eyes closed. Of the 52 participants screened, 25 were randomly assigned to experimental and control groups each. Both interventions were effective for improving the FRT between the baseline and intervention; however, smaller improvements were observed in the experimental group. We found a large between-groups effect size immediately after the intervention for the FRT (d = -0.92). In contrast, there were no differences in improvements in OLST between the 2 groups (d = -0.06); furthermore, neither intervention was found to be effective for this parameter. We concluded that subliminal priming with conscious reward stimuli results in improvements in immediate-term forward reach ability, which is superior to that achieved by subliminal priming with subconscious reward stimuli.

  7. Effect of early amniotomy on dystocia risk and cesarean delivery in nulliparous women: a randomized clinical trial.

    PubMed

    Ghafarzadeh, Masoomeh; Moeininasab, Samira; Namdari, Mehrdad

    2015-08-01

    Artificial rupture of amniotic membranes (amniotomy) which induces or accelerates labor is the most common obstetrical procedure. There is controversy about the effect of early amniotomy on dystocia and cesarean delivery. The study aim was to determine the effect of early amniotomy on the risk of dystocia and cesarean delivery in nulliparous women. This randomized controlled clinical trial was conducted on 300 nulliparous women. They were randomly assigned into the experimental (early amniotomy; artificial amniotomy at cervical dilation ≤ 4 cm) and control (routine management) groups (each 150 women). Length of labor, dystocia, cesarean delivery, placental abruption, and umbilical cord prolapse were compared between the groups. Early amniotomy shortened labor duration significantly in experimental group (7.5 ± 0.7 h) compared to control group (9.9 ± 1.0 h) (P < 0.001). Dystocia (6.7 vs. 25.3 %, P < 0.0001), cesarean delivery (11.3 vs. 39.3 %, P < 0.001), and placental abruption (4.7 vs. 13.3 %, P = 0.009) were significantly lower in experimental group compared to the control group. Multiple logistic regression showed that early amniotomy decreased the odds of dystocia 80.6 % (95 % CI 58.6-90.1 %) and the odds of cesarean section 81.7 % (95 % CI 66.2-90.1 %). Early amniotomy was associated with lower rate of dystocia and cesarean delivery as well as shorter duration of labor.

  8. Effect of facial neuromuscular re-education on facial symmetry in patients with Bell's palsy: a randomized controlled trial.

    PubMed

    Manikandan, N

    2007-04-01

    To determine the effect of facial neuromuscular re-education over conventional therapeutic measures in improving facial symmetry in patients with Bell's palsy. Randomized controlled trial. Neurorehabilitation unit. Fifty-nine patients diagnosed with Bell's palsy were included in the study after they met the inclusion criteria. Patients were randomly divided into two groups: control (n = 30) and experimental (n = 29). Control group patients received conventional therapeutic measures while the facial neuromuscular re-education group patients received techniques that were tailored to each patient in three sessions per day for six days per week for a period of two weeks. All the patients were evaluated using a Facial Grading Scale before treatment and after three months. The Facial Grading Scale scores showed significant improvement in both control (mean 32 (range 9.7-54) to 54.5 (42.2-71.7)) and the experimental (33 (18-43.5) to 66 (54-76.7)) group. Facial Grading Scale change scores showed that experimental group (27.5 (20-43.77)) improved significantly more than the control group (16.5 (12.2-24.7)). Analysis of Facial Grading Scale subcomponents did not show statistical significance, except in the movement score (12 (8-16) to 24 (12-18)). Individualized facial neuromuscular re-education is more effective in improving facial symmetry in patients with Bell's palsy than conventional therapeutic measures.

  9. Empirical Modeling Of Single-Event Upset

    NASA Technical Reports Server (NTRS)

    Zoutendyk, John A.; Smith, Lawrence S.; Soli, George A.; Thieberger, Peter; Smith, Stephen L.; Atwood, Gregory E.

    1988-01-01

    Experimental study presents examples of empirical modeling of single-event upset in negatively-doped-source/drain metal-oxide-semiconductor static random-access memory cells. Data supports adoption of simplified worst-case model in which cross sectionof SEU by ion above threshold energy equals area of memory cell.

  10. Immediate effect of a functional wrist orthosis for children with cerebral palsy or brain injury: A randomized controlled trial.

    PubMed

    Jackman, Michelle; Novak, Iona; Lannin, Natasha; Galea, Claire

    2017-10-28

    Two-group randomized controlled trial. Upper limb orthoses worn during functional tasks are commonly used in pediatric neurologic rehabilitation, despite a paucity of high-level evidence. The purpose of this study was to investigate if a customized functional wrist orthosis, when placed on the limb, leads to an immediate improvement in hand function for children with cerebral palsy or brain injury. A 2-group randomized controlled trial involving 30 children was conducted. Participants were randomized to either receive a customized functional wrist orthosis (experimental, n = 15) or not receive an orthosis (control, n = 15). The box and blocks test was administered at baseline and repeated 1 hour after experimental intervention, with the orthosis on if randomized to the orthotic group. After intervention, there were no significant differences on the box and blocks test between the orthotic group (mean, 10.13; standard deviation, 11.476) and the no orthotic group (mean, 14.07; standard deviation, 11.106; t[28], -0.954; P = .348; and 95% confidence interval, -12.380 to 4.513). In contrast to the findings of previous studies, our results suggest that a functional wrist orthosis, when supporting the joint in a 'typical' position, may not lead to an immediate improvement in hand function. Wearing a functional wrist orthosis did not lead to an immediate improvement in the ability of children with cerebral palsy or brain injury to grasp and release. Further research is needed combining upper limb orthoses with task-specific training and measuring outcomes over the medium to long term. Copyright © 2017 Hanley & Belfus. All rights reserved.

  11. Efficacy of aquatic therapy for multiple sclerosis: a systematic review.

    PubMed

    Corvillo, Iluminada; Varela, Enrique; Armijo, Francisco; Alvarez-Badillo, Antonio; Armijo, Onica; Maraver, Francisco

    2017-12-01

    Multiple sclerosis (MS) is a chronic, inflammatory, progressive, disabling autoimmune disease affecting the central nervous system. Symptoms and signs of MS vary widely and patients may lose their ability to walk. To date the benefits of aquatic therapy often used for rehabilitation in MS patients have not been reviewed. The aim of this study was to systematically review the current state of aquatic treatment for persons with MS (hydrotherapy, aquatic therapy, aquatic exercises, spa therapy) and to evaluate the scientific evidence supporting the benefits of this therapeutic option. The databases PubMed, Scopus, WoS and PEDro were searched to identify relevant reports published from January 1, 2011 to April 30, 2016. Of 306 articles identified, only 10 fulfilled the inclusion criteria: 5 randomized controlled, 2 simple randomized quasi-experimental, 1 semi-experimental, 1 blind controlled pilot and 1 pilot. Evidence that aquatic treatment improves quality of life in affected patients was very good in two studies, good in four, fair in two and weak in two.

  12. The effect of combined stimulation of external cold and vibration during immunization on pain and anxiety levels in children.

    PubMed

    Canbulat Şahiner, Nejla; İnal, Sevil; Sevim Akbay, Ayşe

    2015-06-01

    Procedures involving needles are the most common and major sources of pain in children. External cold and vibration via Buzzy (MMJ Labs, Atlanta, GA) is a method that combines cooling and vibration. This study investigated the effect of the combined stimulation of skin with external cold and vibration via Buzzy on the pain and anxiety levels in children during immunization. This study was a prospective, randomized controlled trial. Children were randomized into two groups: experimental (external cold and Buzzy) and control (no intervention). The pain and anxiety levels of the children were assessed using the Wong-Baker FACES scale and Children Fear Scale. The experimental group showed significantly lower pain and anxiety levels than the control group during immunization. The combined stimulation of skin with external cold and vibration can be used to reduce pain and anxiety during pediatric immunization. Copyright © 2015 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.

  13. Intention-to-Treat Analysis in Partially Nested Randomized Controlled Trials with Real-World Complexity

    ERIC Educational Resources Information Center

    Schweig, Jonathan David; Pane, John F.

    2016-01-01

    Demands for scientific knowledge of what works in educational policy and practice has driven interest in quantitative investigations of educational outcomes, and randomized controlled trials (RCTs) have proliferated under these conditions. In educational settings, even when individuals are randomized, both experimental and control students are…

  14. DNA asymmetry in stem cells - immortal or mortal?

    PubMed

    Yadlapalli, Swathi; Yamashita, Yukiko M

    2013-09-15

    The immortal strand hypothesis proposes that stem cells retain a template copy of genomic DNA (i.e. an 'immortal strand') to avoid replication-induced mutations. An alternative hypothesis suggests that certain cells segregate sister chromatids non-randomly to transmit distinct epigenetic information. However, this area of research has been highly controversial, with conflicting data even from the same cell types. Moreover, historically, the same term of 'non-random sister chromatid segregation' or 'biased sister chromatid segregation' has been used to indicate distinct biological processes, generating a confusion in the biological significance and potential mechanism of each phenomenon. Here, we discuss the models of non-random sister chromatid segregation, and we explore the strengths and limitations of the various techniques and experimental model systems used to study this question. We also describe our recent study on Drosophila male germline stem cells, where sister chromatids of X and Y chromosomes are segregated non-randomly during cell division. We aim to integrate the existing evidence to speculate on the underlying mechanisms and biological relevance of this long-standing observation on non-random sister chromatid segregation.

  15. DNA asymmetry in stem cells – immortal or mortal?

    PubMed Central

    Yadlapalli, Swathi; Yamashita, Yukiko M.

    2013-01-01

    Summary The immortal strand hypothesis proposes that stem cells retain a template copy of genomic DNA (i.e. an ‘immortal strand’) to avoid replication-induced mutations. An alternative hypothesis suggests that certain cells segregate sister chromatids non-randomly to transmit distinct epigenetic information. However, this area of research has been highly controversial, with conflicting data even from the same cell types. Moreover, historically, the same term of ‘non-random sister chromatid segregation’ or ‘biased sister chromatid segregation’ has been used to indicate distinct biological processes, generating a confusion in the biological significance and potential mechanism of each phenomenon. Here, we discuss the models of non-random sister chromatid segregation, and we explore the strengths and limitations of the various techniques and experimental model systems used to study this question. We also describe our recent study on Drosophila male germline stem cells, where sister chromatids of X and Y chromosomes are segregated non-randomly during cell division. We aim to integrate the existing evidence to speculate on the underlying mechanisms and biological relevance of this long-standing observation on non-random sister chromatid segregation. PMID:23970416

  16. Reducing cancer screening disparities in medicare beneficiaries through cancer patient navigation.

    PubMed

    Braun, Kathryn L; Thomas, William L; Domingo, Jermy-Leigh B; Allison, Amanda L; Ponce, Avette; Haunani Kamakana, P; Brazzel, Sandra S; Emmett Aluli, N; Tsark, JoAnn U

    2015-02-01

    Significant racial disparities in cancer mortality are seen between Medicare beneficiaries. A randomized controlled trial tested the use of lay navigators (care managers) to increase cancer screening of Asian and Pacific Islander Medicare beneficiaries. The study setting was Moloka'i General Hospital on the island of Moloka'i, Hawai'i, which was one of six sites participating in the Cancer Prevention and Treatment Demonstration sponsored by the Centers for Medicare and Medicaid Services. Between 2006 and 2009, 488 Medicare beneficiaries (45% Hawaiian, 35% Filipino, 11% Japanese, 8% other) were randomized to have a navigator help them access cancer screening services (experimental condition, n = 242) or cancer education (control condition, n = 246). Self-reported data on screening participation were collected at baseline and exit from the study, and differences were tested using chi-square. Groups were similar in demographic characteristics and baseline screening prevalence of breast, cervical, prostate, and colorectal cancers. At study exit, 57.0% of women in the experimental arm and 36.4% of controls had had a Papanicolaou test in the past 24 months (P = .001), 61.7% of women in the experimental arm and 42.4% of controls had had a mammogram in the past 12 months (P = .003), 54.4% of men in the experimental arm and 36.0% of controls had had a prostate-specific antigen test in the past 12 months (P = .008), and 43.0% of both sexes in the experimental arm and 27.2% of controls had had a flexible sigmoidoscopy or colonoscopy in the past 5 years (P < .001). Findings suggest that navigation services can increase cancer screening in Medicare beneficiaries in groups with significant disparities. © 2015, Copyright the Authors Journal compilation © 2015, The American Geriatrics Society.

  17. Effects of a price increase on purchases of sugar sweetened beverages. Results from a randomized controlled trial.

    PubMed

    Waterlander, Wilma Elzeline; Ni Mhurchu, Cliona; Steenhuis, Ingrid H M

    2014-07-01

    Sugar sweetened beverage (SSB) taxes are receiving increased political interest. However, there have been no experimental studies of the effects of price increases on SSBs or the effects on close substitutes such as diet drinks, alcohol or sugary snacks. Therefore, the aim of this study was to examine the effects of a price increase on SSBs on beverage and snack purchases using a randomized controlled design within a three-dimensional web-based supermarket. The trial contained two conditions: experimental condition with a 19% tax on SSBs (to reflect an increase in Dutch value added tax from 6% to 19%); and a control condition with regular prices. N = 102 participants were randomized and purchased groceries on a single occasion at a three-dimensional Virtual Supermarket. Data were analysed using independent t-tests and regression analysis. Results showed that participants in the price increase condition purchased significantly less SSBs than the control group (B = -.90; 95% CI = -1.70 to -.10 L per household per week). There were no significant effects on purchases in other beverage or snack food categories. This means that the higher VAT rate was effective in reducing SSB purchases and had no negative side-effects. Copyright © 2014. Published by Elsevier Ltd.

  18. Effectiveness of a theory-based mobile phone text message intervention for improving protective behaviors of pregnant women against air pollution: a randomized controlled trial.

    PubMed

    Jasemzadeh, Mehrnoosh; Khafaie, Morteza Abdullatif; Jaafarzadeh, Nematallah; Araban, Marzieh

    2018-03-01

    Health impact of exposure to air pollution is a public health concern. The aim of this study was to investigate an extended parallel process model (EPPM)-based mobile phone text message intervention for improving protective behaviors against air pollution among pregnant women. In this randomized controlled trial (IRCT2016102810804N8), 130 pregnant women were randomly assigned into either experimental or control groups. A valid and reliable questionnaire was used to collect data. Experimental group received mobile phone intervention on a daily basis for 2 months. Control group received usual care, only. Data were analyzed using SPSS 15 applying t test, chi-square, and Wilcoxon and Mann-Whitney U test. Although before intervention, there were no significant differences between different structures of EPPM (P > 0.05), after intervention, there were statistically significant differences between perceived severity, response efficacy, self-efficacy, and protective behaviors between two groups (P < 0.05). Implementing EPPM based-mobile phone intervention could promote protective behaviors against air pollution among pregnant women. The present study might be used as a framework for evidence-based health promotion regarding air pollution risk communication and self-care behaviors. IRCT2016102810804N8.

  19. Blinded interpretation of study results can feasibly and effectively diminish interpretation bias.

    PubMed

    Järvinen, Teppo L N; Sihvonen, Raine; Bhandari, Mohit; Sprague, Sheila; Malmivaara, Antti; Paavola, Mika; Schünemann, Holger J; Guyatt, Gordon H

    2014-07-01

    Controversial and misleading interpretation of data from randomized trials is common. How to avoid misleading interpretation has received little attention. Herein, we describe two applications of an approach that involves blinded interpretation of the results by study investigators. The approach involves developing two interpretations of the results on the basis of a blinded review of the primary outcome data (experimental treatment A compared with control treatment B). One interpretation assumes that A is the experimental intervention and another assumes that A is the control. After agreeing that there will be no further changes, the investigators record their decisions and sign the resulting document. The randomization code is then broken, the correct interpretation chosen, and the manuscript finalized. Review of the document by an external authority before finalization can provide another safeguard against interpretation bias. We found the blinded preparation of a summary of data interpretation described in this article practical, efficient, and useful. Blinded data interpretation may decrease the frequency of misleading data interpretation. Widespread adoption of blinded data interpretation would be greatly facilitated were it added to the minimum set of recommendations outlining proper conduct of randomized controlled trials (eg, the Consolidated Standards of Reporting Trials statement). Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Evaluation of empowerment model on indicators of metabolic control in patients with type 2 diabetes, a randomized clinical trial study.

    PubMed

    Ebrahimi, Hossein; Sadeghi, Mahdi; Amanpour, Farzaneh; Vahedi, Hamid

    2016-04-01

    Diabetes education is a major subject in achieving optimal glycemic control. Effective empowerment approach can be beneficial for improving patients' health. The aim of this study was to evaluate the effect of empowerment model on indicators of metabolic control in patients with type 2 diabetes. a randomized controlled trial of 103 patients with type 2 diabetes were randomly assigned to either the intervention (empowerment approach training) or the control group (conventional training) 2014. Empowerment approach training were performed for the experimental group for eight weeks. Data collection tool included demographic information form and indicators of metabolic control checklist. Analysis was performed by one-way analysis of variance, chi-square test, paired t-test, independent t-test and multiple linear regression. Before the intervention, two groups were homogeneous in terms of demographic variables, glycosylated hemoglobin (HbA1C), and other indicators of metabolic control. After the intervention, average HbA1C and other metabolic indicators except for LDL showed significant differences in the experimental group compared to the control group. study results indicated the positive effects of applying the empowerment model on the metabolic control indicators. Therefore, applying this model is recommended to nurses and the relevant authorities in order to improve clinical outcomes in diabetic patients. Copyright © 2015 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.

  1. Effects of Practical Activities and Manual on Science Students' Academic Performance on Solubility in Uruan Local Education Authority of Akwa Ibom State

    ERIC Educational Resources Information Center

    Etiubon, Rebecca Ufonabasi; Udoh, Nsimeneabasi Michael

    2017-01-01

    This study investigated the effects of practical activities and manual on science students' academic performance on solubility in Uruan Local Education Authority of Akwa Ibom State. The study adopted pretest, posttest non randomized quasi experimental design. Three research questions and three hypotheses were formulated to guide the study. One…

  2. A Comparative Study on the Teaching Effects of TRIZ Courses for the Humanities

    ERIC Educational Resources Information Center

    Luo, Lingling; Li, Peng; Zhang, Ping

    2017-01-01

    In order to test the feasibility of the curriculum system of TRIZ used in humanities and social science majors, this study will test whether it is effective to cultivate students' creativity and to train their ability to solve problems. This study designs the randomly experimental targets in the two control groups for pretest and post-test. This…

  3. Improving Reading Comprehension Skills with Children's Books through Metacognitive Strategy: The Turkish Context

    ERIC Educational Resources Information Center

    Çer, Erkan; Sahin, Ertugrul

    2016-01-01

    The aim of this study was to explore the effect of metacognitive strategy in improving reading comprehension skills through children's literature of literary quality. A quasi-experimental study was carried out in a private secondary school in a city located Middle Black Sea region of Turkey. Two classes were randomly chosen as the study group, and…

  4. Effect of Self-Instruction Strategy on the Achievement in Algebra of Students with Learning Difficulty in Mathematics

    ERIC Educational Resources Information Center

    Adani, Anthony; Eskay, Michael; Onu, Victoria

    2012-01-01

    This quasi-experimental study examined the effect of self-instruction strategy on the achievement in algebra of students with learning difficulty in mathematics. Two research questions and one null hypothesis were formulated to guide the study. The study adopted a non-randomized pre-test and post-test control group design with one experimental…

  5. Identity Entrepreneurship and the Consequences of Identity Failure: The Dynamics of Leadership in the BBC Prison Study

    ERIC Educational Resources Information Center

    Haslam, S. Alexander; Reicher, Stephen

    2007-01-01

    The BBC Prison Study was an experimental case study in which participants were randomly assigned to groups as prisoners or guards. This paper examines the impact of interventions designed to increase prisoners' sense of shared social identity on processes of leadership. It presents psychometric, behavioral, and observational data which support the…

  6. Towards Working Life: Effects of an Intervention on Mental Health and Transition to Post-Basic Education

    ERIC Educational Resources Information Center

    Vuori, Jukka; Koivisto, Petri; Mutanen, Pertti; Jokisaari, Markku; Salmela-Aro, Katariina

    2008-01-01

    The Towards Working Life group method was designed to promote the transition to the upper secondary level or vocational studies and to support mental health among young people finishing their basic education. This study examined the effects of the intervention during upper secondary and vocational studies in a randomized field experimental study…

  7. Consequences of non-random species loss for decomposition dynamics: Experimental evidence for additive and non-additive effects

    Treesearch

    Becky A. Ball; Mark D. Hunter; John S. Kominoski; Christopher M. Swan; Mark A. Bradford

    2008-01-01

    Although litter decomposition is a fundamental ecological process, most of our understanding comes from studies of single-species decay. Recently, litter-mixing studies have tested whether monoculture data can be applied to mixed-litter systems. These studies have mainly attempted to detect non-additive effects of litter mixing, which address potential consequences of...

  8. Effect of Self Regulated Learning Approach on Junior Secondary School Students' Achievement in Basic Science

    ERIC Educational Resources Information Center

    Nwafor, Chika E.; Obodo, Abigail Chikaodinaka; Okafor, Gabriel

    2015-01-01

    This study explored the effect of self-regulated learning approach on junior secondary school students' achievement in basic science. Quasi-experimental design was used for the study.Two co-educational schools were drawn for the study through simple random sampling technique. One school was assigned to the treatment group while the other was…

  9. Assessing the Long-Term Effects of EMDR: Results from an 18-Month Follow-Up Study with Adult Female Survivors of CSA

    ERIC Educational Resources Information Center

    Edmond, Tonya; Rubin, Allen

    2004-01-01

    This 18-month follow-up study builds on the findings of a randomized experimental evaluation that found qualified support for the short-term effectiveness of Eye Movement Desensitization and Reprocessing (EMDR) in reducing trauma symptoms among adult female survivors of childhood sexual abuse (CSA). The current study provides preliminary evidence…

  10. The conditional power of randomization tests for single-case effect sizes in designs with randomized treatment order: A Monte Carlo simulation study.

    PubMed

    Michiels, Bart; Heyvaert, Mieke; Onghena, Patrick

    2018-04-01

    The conditional power (CP) of the randomization test (RT) was investigated in a simulation study in which three different single-case effect size (ES) measures were used as the test statistics: the mean difference (MD), the percentage of nonoverlapping data (PND), and the nonoverlap of all pairs (NAP). Furthermore, we studied the effect of the experimental design on the RT's CP for three different single-case designs with rapid treatment alternation: the completely randomized design (CRD), the randomized block design (RBD), and the restricted randomized alternation design (RRAD). As a third goal, we evaluated the CP of the RT for three types of simulated data: data generated from a standard normal distribution, data generated from a uniform distribution, and data generated from a first-order autoregressive Gaussian process. The results showed that the MD and NAP perform very similarly in terms of CP, whereas the PND performs substantially worse. Furthermore, the RRAD yielded marginally higher power in the RT, followed by the CRD and then the RBD. Finally, the power of the RT was almost unaffected by the type of the simulated data. On the basis of the results of the simulation study, we recommend at least 20 measurement occasions for single-case designs with a randomized treatment order that are to be evaluated with an RT using a 5% significance level. Furthermore, we do not recommend use of the PND, because of its low power in the RT.

  11. The effects of guided inquiry instruction on student achievement in high school biology

    NASA Astrophysics Data System (ADS)

    Vass, Laszlo

    The purpose of this quantitative, quasi-experimental study was to measure the effect of a student-centered instructional method called guided inquiry on the achievement of students in a unit of study in high school biology. The study used a non-random sample of 109 students, the control group of 55 students enrolled in high school one, received teacher centered instruction while the experimental group of 54 students enrolled at high school two received student-centered, guided inquiry instruction. The pretest-posttest design of the study analyzed scores using an independent t-test, a dependent t-test (p = <.001), an ANCOVA (p = .007), mixed method ANOVA (p = .024) and hierarchical linear regression (p = <.001). The experimental group that received guided inquiry instruction had statistically significantly higher achievement than the control group.

  12. Effects of 4% Icodextrin on Experimental Spinal Epidural Fibrosis.

    PubMed

    Karanci, Turker; Kelten, Bilal; Karaoglan, Alper; Cinar, Nilgun; Midi, Ahmet; Antar, Veysel; Akdemir, Hidayet; Kara, Zeynep

    2017-01-01

    The aim of this experimental study was to investigate whether spinal epidural 4% glucose polymer solution is effective in the prevention of postoperative fibrosis. Twenty eight adult Wistar albino rats were randomly divided into two equal groups, including treatment and control. Both groups underwent L1 vertebral total laminectomy to expose the dura. Topical treatment group received 4% icodextrin. Four weeks later, epidural fibrosis was examined in both groups histologically, biochemically and macroscopically. Topical use of 4% icodextrin prevented significantly epidural fibrosis following the laminectomy operation. Topical 4% icodextrin application inhibits postoperative epidural fibrosis with various mechanisms and prevents adhesions by playing barrier role between tissue surfaces through flotation. Our study is first to present evidence of experimental epidural fibrosis prevention with 4% icodextrin.

  13. Quasi-Experimental Designs for Causal Inference

    ERIC Educational Resources Information Center

    Kim, Yongnam; Steiner, Peter

    2016-01-01

    When randomized experiments are infeasible, quasi-experimental designs can be exploited to evaluate causal treatment effects. The strongest quasi-experimental designs for causal inference are regression discontinuity designs, instrumental variable designs, matching and propensity score designs, and comparative interrupted time series designs. This…

  14. Experimental cancellation of aberrations in intensity correlation in classical optics

    NASA Astrophysics Data System (ADS)

    Jesus-Silva, A. J.; Silva, Juarez G.; Monken, C. H.; Fonseca, E. J. S.

    2018-01-01

    We study the classical correlation function of spatially incoherent beams with a phase aberration in the beam path. On the basis of our experimental measurements and in the optical coherence theory, we show that the effects of phase disturbances, independently of their kind and without need of coordinate inversion, can be canceled out if the same phase is aligned in the signal and reference beam path. These results can be useful for imaging and microscopy through random media.

  15. The Impact of Conferencing Assessment on EFL Students' Grammar Learning (Impacto de la evaluación mediante conferencias en el aprendizaje de la gramática en estudiantes de inglés como lengua extranjera)

    ERIC Educational Resources Information Center

    Baleghizadeh, Sasan; Zarghami, Zahra

    2012-01-01

    This article reports on a study that was carried out in order to examine the impact of conferencing assessment on students' learning of English grammar. Forty-two Iranian intermediate university students were randomly assigned to an experimental and a control group. The participants in the experimental group took part in four individual and four…

  16. Analytical connection between thresholds and immunization strategies of SIS model in random networks

    NASA Astrophysics Data System (ADS)

    Zhou, Ming-Yang; Xiong, Wen-Man; Liao, Hao; Wang, Tong; Wei, Zong-Wen; Fu, Zhong-Qian

    2018-05-01

    Devising effective strategies for hindering the propagation of viruses and protecting the population against epidemics is critical for public security and health. Despite a number of studies based on the susceptible-infected-susceptible (SIS) model devoted to this topic, we still lack a general framework to compare different immunization strategies in completely random networks. Here, we address this problem by suggesting a novel method based on heterogeneous mean-field theory for the SIS model. Our method builds the relationship between the thresholds and different immunization strategies in completely random networks. Besides, we provide an analytical argument that the targeted large-degree strategy achieves the best performance in random networks with arbitrary degree distribution. Moreover, the experimental results demonstrate the effectiveness of the proposed method in both artificial and real-world networks.

  17. An evaluation of the hypolipidemic effect of an extract of Hibiscus Sabdariffa leaves in hyperlipidemic Indians: a double blind, placebo controlled trial.

    PubMed

    Kuriyan, Rebecca; Kumar, Divya R; R, Rajendran; Kurpad, Anura V

    2010-06-17

    Hibiscus sabdariffa is used regularly in folk medicine to treat various conditions. The study was a double blind, placebo controlled, randomized trial. Sixty subjects with serum LDL values in the range of 130-190 mg/dl and with no history of coronary heart disease were randomized into experimental and placebo groups. The experimental group received 1 gm of the extract for 90 days while the placebo received a similar amount of maltodextrin in addition to dietary and physical activity advice for the control of their blood lipids. Anthropometry, blood biochemistry, dietary and physical activity were assessed at baseline, day 45 and day 90. While body weight, serum LDL cholesterol and triglyceride levels decreased in both groups, there were no significant differences between the experimental and placebo group. It is likely that the observed effects were as a result of the patients following the standard dietary and physical activity advice. At a dose of 1 gm/day, hibiscus sabdariffa leaf extract did not appear to have a blood lipid lowering effect. REFCTRI2009000472.

  18. The effects of lavender aromatherapy on pain following needle insertion into a fistula in hemodialysis patients.

    PubMed

    Bagheri-Nesami, Masoumeh; Espahbodi, Fatemeh; Nikkhah, Attieh; Shorofi, Seyed Afshin; Charati, Jamshid Yazdani

    2014-02-01

    This study sought to determine the effects of lavender aromatherapy on pain following needle insertion into a fistula in patients undergoing hemodialysis. This is a randomized controlled clinical trial in which 92 patients undergoing hemodialysis with arteriovenous fistulas were randomly divided into two groups. The experimental-group patients inhaled lavender essence with a concentration of 10% for 5 min during 3 hemodialysis sessions, while the control-group patients received aromatherapy free of lavender essence. The mean VAS pain intensity score in the experimental and control groups before the intervention was 3.78 ± 0.24 and 4.16 ± 0.32, respectively (p = 0.35). The mean VAS pain intensity score in the experimental and control groups after three aromatherapy sessions was 2.36 ± 0.25 and 3.43 ± 0.31, respectively (p = 0.009). Lavender aromatherapy may be an effective technique to reduce pain following needle insertion into a fistula in hemodialysis patients. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Learning to Dislike Chocolate: Conditioning Negative Attitudes toward Chocolate and Its Effect on Chocolate Consumption.

    PubMed

    Wang, Yan; Wang, Guosen; Zhang, Dingyuan; Wang, Lei; Cui, Xianghua; Zhu, Jinglei; Fang, Yuan

    2017-01-01

    Evaluative conditioning (EC) procedures can be used to form and change attitudes toward a wide variety of objects. The current study examined the effects of a negative EC procedure on attitudes toward chocolate, and whether it influenced chocolate evaluation and consumption. Participants were randomly assigned to the experimental condition in which chocolate images were paired with negative stimuli, or the control condition in which chocolate images were randomly paired with positive stimuli (50%) and negative stimuli (50%). Explicit and implicit attitudes toward chocolate images were collected. During an ostensible taste test, chocolate evaluation and consumption were assessed. Results revealed that compared to participants in the control condition, participants in the experimental condition showed more negative explicit and implicit attitudes toward chocolate images and evaluated chocolate more negatively during the taste test. However, chocolate consumption did not differ between experimental and control conditions. These findings suggest that pairing chocolate with negative stimuli can influence attitudes toward chocolate, though behavioral effects are absent. Intervention applications of EC provide avenues for future research and practices.

  20. Learning to Dislike Chocolate: Conditioning Negative Attitudes toward Chocolate and Its Effect on Chocolate Consumption

    PubMed Central

    Wang, Yan; Wang, Guosen; Zhang, Dingyuan; Wang, Lei; Cui, Xianghua; Zhu, Jinglei; Fang, Yuan

    2017-01-01

    Evaluative conditioning (EC) procedures can be used to form and change attitudes toward a wide variety of objects. The current study examined the effects of a negative EC procedure on attitudes toward chocolate, and whether it influenced chocolate evaluation and consumption. Participants were randomly assigned to the experimental condition in which chocolate images were paired with negative stimuli, or the control condition in which chocolate images were randomly paired with positive stimuli (50%) and negative stimuli (50%). Explicit and implicit attitudes toward chocolate images were collected. During an ostensible taste test, chocolate evaluation and consumption were assessed. Results revealed that compared to participants in the control condition, participants in the experimental condition showed more negative explicit and implicit attitudes toward chocolate images and evaluated chocolate more negatively during the taste test. However, chocolate consumption did not differ between experimental and control conditions. These findings suggest that pairing chocolate with negative stimuli can influence attitudes toward chocolate, though behavioral effects are absent. Intervention applications of EC provide avenues for future research and practices. PMID:28900409

  1. Asymptotic laws for random knot diagrams

    NASA Astrophysics Data System (ADS)

    Chapman, Harrison

    2017-06-01

    We study random knotting by considering knot and link diagrams as decorated, (rooted) topological maps on spheres and pulling them uniformly from among sets of a given number of vertices n, as first established in recent work with Cantarella and Mastin. The knot diagram model is an exciting new model which captures both the random geometry of space curve models of knotting as well as the ease of computing invariants from diagrams. We prove that unknot diagrams are asymptotically exponentially rare, an analogue of Sumners and Whittington’s landmark result for self-avoiding polygons. Our proof uses the same key idea: we first show that knot diagrams obey a pattern theorem, which describes their fractal structure. We examine how quickly this behavior occurs in practice. As a consequence, almost all diagrams are asymmetric, simplifying sampling from this model. We conclude with experimental data on knotting in this model. This model of random knotting is similar to those studied by Diao et al, and Dunfield et al.

  2. High-dose levofloxacin in community-acquired pneumonia: a randomized, open-label study.

    PubMed

    Lee, Jin Hwa; Kim, Seo Woo; Kim, Ji Hye; Ryu, Yon Ju; Chang, Jung Hyun

    2012-09-01

    The conventional treatment for community-acquired pneumonia (CAP) involves combination therapy consisting of a β-lactam penicillin or a cephalosporin with a macrolide. Alternatively, high-dose levofloxacin treatment has been used as single-agent therapy for treating CAP, covering atypical pathogens. This study compared the clinical efficacy and safety of high-dose levofloxacin with combined ceftriaxone and azithromycin for the treatment of CAP. This phase IV, prospective, randomized, open-label trial enrolled patients admitted to a tertiary referral hospital for CAP treatment from 2010 to 2011. Hospital admission was decided based on clinical judgement and the pneumonia severity index. Forty subjects were enrolled and assigned to two treatment arms using a random numbers table. The 20 subjects in the experimental group were given levofloxacin 750 mg intravenously once daily, followed by the same dose of oral levofloxacin at discharge when clinically improved and the 20 subjects in the control group were given ceftriaxone 2.0 g intravenously once daily plus oral azithromycin 500 mg for 3 consecutive days, followed by oral cefpodoxime 200 mg per day at discharge after clinical improvement. The primary outcome was the clinical success rate. Secondary outcomes were the microbiological success rate and adverse events during the study. Of the 40 subjects enrolled, 36 completed the study: 17 in the experimental group and 19 in the control group. The groups did not differ in terms of demographic factors or clinical findings at baseline. The clinical success rate (cured + improved) was 94% in the experimental (levofloxacin) group and 84% in the control group (p > 0.05). The microbiological success rate and overall adverse events were also similar in both groups. Single-agent, high-dose levofloxacin treatment exhibited excellent clinical and microbiological efficacy with a safety profile comparable to that of ceftriaxone plus azithromycin therapy. Large-scale clinical trials are required to verify these results. WHO International Clinical Trials Registry: KCT0000374; Daiichi-Sankyo Korea study code: T11-13-V1.

  3. Reducing patients’ suicide ideation through training mental health teams in the application of the Dutch multidisciplinary practice guideline on assessment and treatment of suicidal behavior: study protocol of a randomized controlled trial

    PubMed Central

    2013-01-01

    Background To strengthen suicide prevention skills in mental health care in The Netherlands, multidisciplinary teams throughout the country are trained in the application of the new Dutch guideline on the assessment and treatment of suicidal behavior. Previous studies have shown beneficial effects of additional efforts for guideline implementation on professionals’ attitude, knowledge, and skills. However, the effects on patients are equally important, but are rarely measured. The main objective of this study is to examine whether patients of multidisciplinary teams who are trained in guideline application show greater recovery from suicide ideation than patients of untrained teams. Methods/Design This is a multicentre cluster randomized controlled trial (RCT), in which multidisciplinary teams from mental health care institutions are matched in pairs, and randomly allocated to either the experimental or control condition. In the experimental condition, next to the usual dissemination of the guideline (internet, newsletter, books, publications, and congresses), teams will be trained in the application of the guideline via a 1-day small interactive group training program supported by e-learning modules. In the control condition, no additional actions next to usual dissemination of the guideline will be undertaken. Assessments at patient level will start when the experimental teams are trained. Assessments will take place upon admission and after 3 months, or earlier if the patient is discharged. The primary outcome is suicide ideation. Secondary outcomes are non-fatal suicide attempts, level of treatment satisfaction, and societal costs. Both a cost-effectiveness and cost-utility analysis will be performed. The effects of the intervention will be examined in multilevel models. Discussion The strengths of this study are the size of the study, RCT design, training of complete multidisciplinary teams, and the willingness of both management and staff to participate. Trial registration Netherlands trial register: NTR3092 PMID:24195781

  4. Long-Term Effects of Strategic Reading Instruction in the Intermediate Elementary Grades

    ERIC Educational Resources Information Center

    Droop, Mienke; van Elsäcker, Willy; Voeten, Marinus J. M.; Verhoeven, Ludo

    2016-01-01

    The purpose of the present study was to examine the effects of a program that offered sustained strategic reading instruction on reading abilities of third and fourth graders. The study was conducted among 1,469 children from 40 schools in the Netherlands. Schools were randomly assigned to either the experimental or control group. Multilevel…

  5. Clay Modeling as a Method to Learn Human Muscles: A Community College Study

    ERIC Educational Resources Information Center

    Motoike, Howard K.; O'Kane, Robyn L.; Lenchner, Erez; Haspel, Carol

    2009-01-01

    The efficacy of clay modeling compared with cat dissection for human muscle identification was examined over two semesters at LaGuardia Community College in Queens, NY. The 181 students in 10 sections in this study were randomly distributed into control (cat dissection) and experimental (clay modeling) groups, and the results of the muscle…

  6. Effect of Polya Problem-Solving Model on Senior Secondary School Students' Performance in Current Electricity

    ERIC Educational Resources Information Center

    Olaniyan, Ademola Olatide; Omosewo, Esther O.; Nwankwo, Levi I.

    2015-01-01

    This study was designed to investigate the Effect of Polya Problem-Solving Model on Senior School Students' Performance in Current Electricity. It was a quasi experimental study of non- randomized, non equivalent pre-test post-test control group design. Three research questions were answered and corresponding three research hypotheses were tested…

  7. Benefits of Early Childhood Interventions across the World: (Under) Investing in the Very Young

    ERIC Educational Resources Information Center

    Nores, Milagros; Barnett, W. Steven

    2010-01-01

    This paper reviews the international (non-U.S.) evidence on the benefits of early childhood interventions. A total of 38 contrasts of 30 interventions in 23 countries were analyzed. It focuses on studies applying a quasi-experimental or random assignment. Studies were coded according to: the type of intervention (cash transfer, nutritional,…

  8. The Effects of Different Pre-Writing Strategies on Iranian EFL Writing Achievement

    ERIC Educational Resources Information Center

    Mahnam, Lily; Nejadansari, Dariush

    2012-01-01

    This study aimed at investigating whether applying pre-writing strategies would affect the quality of L2 learners' compositions. Twenty three adult EFL students from Jahad-e-Daneshgahi English centre in Iran participated in this study. They were randomly assigned to control and experimental groups, including 11 and 12 participants in each. They…

  9. Effects of Psychomotor Intervention Program on Students with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    ElGarhy, Sayed; Liu, Ting

    2016-01-01

    The purpose of this study was to examine the effects of a psychomotor intervention program (PIP) on body awareness and psychomotor concepts for students with autism spectrum disorder (ASD). Twenty-eight students (23 boys and 5 girls) with ASD participated in this study. Fourteen students with ASD were randomly assigned to the experimental group…

  10. The Effect of Choosing versus Receiving Feedback on College Students' Performance

    ERIC Educational Resources Information Center

    Cutumisu, Maria; Schwartz, Daniel L.

    2016-01-01

    This study examines the effect of choosing versus receiving feedback on the learning performance of n = 98 post-secondary students from California on a digital poster design task. The study employs a yoked experimental design where college students are randomly assigned to play a choice-based assessment game, Posterlet, in one of two conditions,…

  11. Implementation of Structured Inquiry Based Model Learning toward Students' Understanding of Geometry

    ERIC Educational Resources Information Center

    Salim, Kalbin; Tiawa, Dayang Hjh

    2015-01-01

    The purpose of this study is implementation of a structured inquiry learning model in instruction of geometry. The model used is a model with a quasi-experimental study amounted to two classes of samples selected from the population of the ten classes with cluster random sampling technique. Data collection tool consists of a test item…

  12. Mediating Role of Parental Influence in Children's Response to Television Commercials: An Exploratory Study.

    ERIC Educational Resources Information Center

    Prasad, V. Kanti; And Others

    This study investigated, in a laboratory experimental framework, the relative influences of television commercials and parental counter-commercial advocacy on children's consumption choice behavior. Sixty-four 8- to 10-year-old boys were randomly assigned to one of three treatment groups: (1) no counter commercial advocacy (control group), (2)…

  13. The Utility of Blended Learning in EFL Reading and Grammar: A Case for Moodle

    ERIC Educational Resources Information Center

    Bataineh, Ruba Fahmi; Mayyas, Mais Barjas

    2017-01-01

    This study examines the effect of Moodle-enhanced instruction on Jordanian EFL students' reading comprehension and grammar performance. The study uses a quasi-experimental, pre- /post-test design. A purposeful sample of 32 students, enrolled in a language requirement course at a Jordanian state university, was randomly divided into an experimental…

  14. Effect of Ethnochemistry Practices on Secondary School Students' Attitude towards Chemistry

    ERIC Educational Resources Information Center

    Singh, Indra Sen; Chibuye, Bitwell

    2016-01-01

    The main purpose of the study was to find out the effect of ethnochemistry practices on secondary school students' attitude towards Chemistry. The design of the study was pre-test post-test control group quasiexperimental design. Two grade 11 intact classes were assigned into experimental and control groups randomly. The total sample size…

  15. Technology Instructional Package Mediated Instruction and Senior Secondary School Students' Academic Performance in Biology Concepts

    ERIC Educational Resources Information Center

    Yaki, Akawo Angwal; Babagana, Mohammed

    2016-01-01

    The paper examined the effects of a Technological Instructional Package (TIP) on secondary school students' performance in biology. The study adopted a pre-test, post-test experimental control group design. The sample size of the study was 80 students from Minna metropolis, Niger state, Nigeria; the samples were randomly assigned into treatment…

  16. Mind Maps to Modify Lack of Attention among Saudi Kindergarten Children

    ERIC Educational Resources Information Center

    Daghistan, Bulquees Ismail Abdul Majid

    2016-01-01

    This research study aims at investigating the impact of Mind Maps on modifying the lack of attention in Arabic language class among Saudi Kindergarten children. To achieve the goals of this study the researcher used an experimental design with a random sample from AlRae'd Kindergarten's children in Riyadh -Saudi Arabia for the academic year…

  17. Effectiveness of Web Quest Strategy in Acquiring Geographic Concepts among Eighth Grade Students in Jordan

    ERIC Educational Resources Information Center

    AL-Edwan, Zaid Suleiman

    2014-01-01

    This study aimed at identifying the Effectiveness of using Web Quest Strategy in acquiring the geographic concepts among eighth grade students in Jordan. The study individuals consisted of (119) students in the scholastic year 2013-2014. Four sections were randomly selected from two schools divided into experimental and control groups. They were…

  18. Can Personalized Nudges Improve Learning in Hybrid Classes? Experimental Evidence from an Introductory Undergraduate Course

    ERIC Educational Resources Information Center

    O'Connell, Stephen D.; Lang, Guido

    2018-01-01

    A field experiment was conducted to investigate whether personalized e-mail reminders can improve study consistency and learning outcomes in an introductory-level undergraduate course. By randomly assigning whether nearly 300 students would receive occasional e-mail messages encouraging out-of-class study, we find that these reminders increased…

  19. Exposure to Metacognitive Skills Improves Academic Performance: An Experimental Study of College Students' Academic Performance and Self-Efficacy

    ERIC Educational Resources Information Center

    Thomas, Pamela

    2016-01-01

    This study examined undergraduate students in four randomly assigned groups, Generative Reading, SQ3R (Robinson, (1946, 1970), and no intervention, and general examinations as the control, to identify which strategy was most beneficial for improving exam scores and academic self-efficacy. Findings suggest students participating in reading…

  20. Successfully Promoting 21st Century Online Research Skills: Interventions in 5th-Grade Classrooms

    ERIC Educational Resources Information Center

    Kingsley, Tara L.; Cassady, Jerrell C.; Tancock, Susan M.

    2015-01-01

    This quantitative study was developed to explore the ability to impact elementary student 21st Century online research skills with a planned classroom intervention curriculum. The repeated measures quasi-experimental study randomly assigned all 5th grade classes in a Midwestern, suburban school (n = 418) to a 12-week intervention or control…

  1. Changes of blood parameters associated with bone remodeling following experimentally induced fatty liver disorder in laying hens

    USDA-ARS?s Scientific Manuscript database

    Studies have demonstrated that obesity and osteoporosis are two linked disorders in humans. This study examined if excessive lipid consumption affects bone metabolism in laying hens. One hundred 63-week-old laying hens were randomly divided into two treatments, i.e., fed with a regular diet (control...

  2. Prediction Accuracy: The Role of Feedback in 6th Graders' Recall Predictions

    ERIC Educational Resources Information Center

    Al-Harthy, Ibrahim S.

    2016-01-01

    The current study focused on the role of feedback on students' prediction accuracy (calibration). This phenomenon has been widely studied, but questions remain about how best to improve it. In the current investigation, fifty-seven students from sixth grade were randomly assigned to control and experimental groups. Thirty pictures were chosen from…

  3. Interventions to Reduce Distress in Adult Victims of Rape and Sexual Violence: A Systematic Review

    ERIC Educational Resources Information Center

    Regehr, Cheryl; Alaggia, Ramona; Dennis, Jane; Pitts, Annabel; Saini, Michael

    2013-01-01

    Objectives: This article presents a systematic evaluation of the effectiveness of interventions aimed at reducing distress in adult victims of rape and sexual violence. Method: Studies were eligible for the review if the assignment of study participants to experimental or control groups was by random allocation or parallel cohort design. Results:…

  4. Does extended proactive telephone support increase smoking cessation among low-income women using nicotine patches?

    PubMed

    Solomon, Laura J; Marcy, Theodore W; Howe, Kathleen D; Skelly, Joan M; Reinier, Kyndaron; Flynn, Brian S

    2005-03-01

    It is unclear whether proactive telephone support enhances smoking cessation beyond the provision of nicotine replacement therapy alone. We randomly assigned 330 low-income women smokers to receive either free nicotine patches (control condition) or free nicotine patches with up to 16 weeks of proactive telephone support (experimental condition). All participants were assessed by telephone at baseline and at 2 weeks, 3 months, and 6 months post-baseline to determine smoking status. Results revealed a significant effect for the telephone support at 3 months, with 43% of experimental versus 26% of control condition women reporting 30-day point prevalent abstinence (P = 0.002). The difference was no longer significant at 6 months. A metaanalysis conducted with five randomized studies revealed a slight but non-significant long-term benefit of proactive telephone support when added to the provision of free nicotine patches for smoking cessation. This is the second study to demonstrate a short-term effect for proactive telephone support added to free nicotine replacement therapy; however, neither the current study, nor the metaanalysis including the four other published trials, confirmed a longer-term benefit.

  5. Quantum Glass of Interacting Bosons with Off-Diagonal Disorder

    NASA Astrophysics Data System (ADS)

    Piekarska, A. M.; Kopeć, T. K.

    2018-04-01

    We study disordered interacting bosons described by the Bose-Hubbard model with Gaussian-distributed random tunneling amplitudes. It is shown that the off-diagonal disorder induces a spin-glass-like ground state, characterized by randomly frozen quantum-mechanical U(1) phases of bosons. To access criticality, we employ the "n -replica trick," as in the spin-glass theory, and the Trotter-Suzuki method for decomposition of the statistical density operator, along with numerical calculations. The interplay between disorder, quantum, and thermal fluctuations leads to phase diagrams exhibiting a glassy state of bosons, which are studied as a function of model parameters. The considered system may be relevant for quantum simulators of optical-lattice bosons, where the randomness can be introduced in a controlled way. The latter is supported by a proposition of experimental realization of the system in question.

  6. Is Sexual Objectification and Victimization of Females in Video Games Associated With Victim Blaming or Victim Empathy?

    PubMed

    Beck, Victoria; Rose, Chris

    2018-04-01

    The goal of this study was to investigate whether the sexual objectification and virtual violence against females in video games increases negative attitudes toward females, when addressing a variety of noted methodological issues. Study participants were randomly assigned to a control group, where participants played Madden NFL 12, or an experimental group, where participants played Grand Theft Auto. In the experimental group, participants played the game with a confederate, who exposed participants to sexual objectification and violence against females. Study results indicated that both the experimental and control groups had equivalently low levels of rape myth acceptance prior to game play. Immediately after game play, there still was no statistically significant difference in rape myth acceptance between groups; however, there was a decrease in rape myth acceptance for the experimental group. The decrease in rape myth acceptance continued and magnified for the experimental group, over time, to the point of creating a statistically significant difference between the two groups for the follow-up measure at the end of the study.

  7. Modeling and experimental study of resistive switching in vertically aligned carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Ageev, O. A.; Blinov, Yu F.; Ilina, M. V.; Ilin, O. I.; Smirnov, V. A.

    2016-08-01

    Model of the resistive switching in vertically aligned carbon nanotube (VA CNT) taking into account the processes of deformation, polarization and piezoelectric charge accumulation have been developed. Origin of hysteresis in VA CNT-based structure is described. Based on modeling results the VACNTs-based structure has been created. The ration resistance of high-resistance to low-resistance states of the VACNTs-based structure amounts 48. The correlation the modeling results with experimental studies is shown. The results can be used in the development nanoelectronics devices based on VA CNTs, including the nonvolatile resistive random-access memory.

  8. 75 FR 9189 - Notice of Proposed Information Collection Requests

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-01

    ... mandated standardized test scores); follow-up surveys for students; teacher and parent rating/observation on various student aspects (e.g., student social skills); baseline and follow-up surveys for teachers... Character (LIC) program. This study is based on an experimental design that utilizes the random assignment...

  9. The State, Not the Trait, of Nostalgia Increases Creativity

    ERIC Educational Resources Information Center

    Ye, Shengquan; Ngan, Rose Ying Lam; Hui, Anna N. N.

    2013-01-01

    Nostalgic experience evokes emotions and activates the cognitive process of recalling and reconstructing information in memory. This study investigated the effects of nostalgia on creativity using experiments and questionnaires. Two-hundred-and-eighty university students were randomly assigned to experimental and control groups, in which…

  10. Experimenter Effects on Cardiovascular Reactivity and Task Performance during Mental Stress Testing

    ERIC Educational Resources Information Center

    Siegwarth, Nicole; Larkin, Kevin T.; Kemmner, Christine

    2012-01-01

    Experimenter effects have long been hypothesized to influence participants' responses to mental stress testing. To explore the influence of experimenter warmth on responses to two mental stress tasks (mental arithmetic, mirror tracing), 32 young women participated in a single 45-min experimental session. Participants were randomized into warm…

  11. Sample Selection in Randomized Experiments: A New Method Using Propensity Score Stratified Sampling

    ERIC Educational Resources Information Center

    Tipton, Elizabeth; Hedges, Larry; Vaden-Kiernan, Michael; Borman, Geoffrey; Sullivan, Kate; Caverly, Sarah

    2014-01-01

    Randomized experiments are often seen as the "gold standard" for causal research. Despite the fact that experiments use random assignment to treatment conditions, units are seldom selected into the experiment using probability sampling. Very little research on experimental design has focused on how to make generalizations to well-defined…

  12. Estimating the Standard Error of the Impact Estimator in Individually Randomized Trials with Clustering

    ERIC Educational Resources Information Center

    Weiss, Michael J.; Lockwood, J. R.; McCaffrey, Daniel F.

    2016-01-01

    In the "individually randomized group treatment" (IRGT) experimental design, individuals are first randomly assigned to a treatment arm or a control arm, but then within each arm, are grouped together (e.g., within classrooms/schools, through shared case managers, in group therapy sessions, through shared doctors, etc.) to receive…

  13. The Effectiveness of Mandatory-Random Student Drug Testing. NCEE 2010-4025

    ERIC Educational Resources Information Center

    James-Burdumy, Susanne; Goesling, Brian; Deke, John; Einspruch, Eric

    2010-01-01

    To help assess the effects of school-based random drug testing programs, the U.S. Department of Education's Institute of Education Sciences (IES) contracted with RMC Research Corporation and Mathematica Policy Research to conduct an experimental evaluation of the Mandatory-Random Student Drug Testing (MRSDT) programs in 36 high schools within…

  14. Effectiveness of a new health care organization model in primary care for chronic cardiovascular disease patients based on a multifactorial intervention: the PROPRESE randomized controlled trial.

    PubMed

    Orozco-Beltran, Domingo; Ruescas-Escolano, Esther; Navarro-Palazón, Ana Isabel; Cordero, Alberto; Gaubert-Tortosa, María; Navarro-Perez, Jorge; Carratalá-Munuera, Concepción; Pertusa-Martínez, Salvador; Soler-Bahilo, Enrique; Brotons-Muntó, Francisco; Bort-Cubero, Jose; Nuñez-Martinez, Miguel Angel; Bertomeu-Martinez, Vicente; Gil-Guillen, Vicente Francisco

    2013-08-02

    To evaluate the effectiveness of a new multifactorial intervention to improve health care for chronic ischemic heart disease patients in primary care. The strategy has two components: a) organizational for the patient/professional relationship and b) training for professionals. Experimental study. Randomized clinical trial. Follow-up period: one year. primary care, multicenter (15 health centers). For the intervention group 15 health centers are selected from those participating in ESCARVAL study. Once the center agreed to participate patients are randomly selected from the total amount of patients with ischemic heart disease registered in the electronic health records. For the control group a random sample of patients with ischemic heart disease is selected from all 72 health centers electronic records. This study aims to evaluate the efficacy of a multifactorial intervention strategy involving patients with ischemic heart disease for the improvement of the degree of control of the cardiovascular risk factors and of the quality of life, number of visits, and number of hospitalizations. NCT01826929.

  15. An AES chip with DPA resistance using hardware-based random order execution

    NASA Astrophysics Data System (ADS)

    Bo, Yu; Xiangyu, Li; Cong, Chen; Yihe, Sun; Liji, Wu; Xiangmin, Zhang

    2012-06-01

    This paper presents an AES (advanced encryption standard) chip that combats differential power analysis (DPA) side-channel attack through hardware-based random order execution. Both decryption and encryption procedures of an AES are implemented on the chip. A fine-grained dataflow architecture is proposed, which dynamically exploits intrinsic byte-level independence in the algorithm. A novel circuit called an HMF (Hold-Match-Fetch) unit is proposed for random control, which randomly sets execution orders for concurrent operations. The AES chip was manufactured in SMIC 0.18 μm technology. The average energy for encrypting one group of plain texts (128 bits secrete keys) is 19 nJ. The core area is 0.43 mm2. A sophisticated experimental setup was built to test the DPA resistance. Measurement-based experimental results show that one byte of a secret key cannot be disclosed from our chip under random mode after 64000 power traces were used in the DPA attack. Compared with the corresponding fixed order execution, the hardware based random order execution is improved by at least 21 times the DPA resistance.

  16. Quasi-experimental study designs series-paper 7: assessing the assumptions.

    PubMed

    Bärnighausen, Till; Oldenburg, Catherine; Tugwell, Peter; Bommer, Christian; Ebert, Cara; Barreto, Mauricio; Djimeu, Eric; Haber, Noah; Waddington, Hugh; Rockers, Peter; Sianesi, Barbara; Bor, Jacob; Fink, Günther; Valentine, Jeffrey; Tanner, Jeffrey; Stanley, Tom; Sierra, Eduardo; Tchetgen, Eric Tchetgen; Atun, Rifat; Vollmer, Sebastian

    2017-09-01

    Quasi-experimental designs are gaining popularity in epidemiology and health systems research-in particular for the evaluation of health care practice, programs, and policy-because they allow strong causal inferences without randomized controlled experiments. We describe the concepts underlying five important quasi-experimental designs: Instrumental Variables, Regression Discontinuity, Interrupted Time Series, Fixed Effects, and Difference-in-Differences designs. We illustrate each of the designs with an example from health research. We then describe the assumptions required for each of the designs to ensure valid causal inference and discuss the tests available to examine the assumptions. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Issues in the design of a clinical trial with a behavioral intervention--the Zambia exclusive breast-feeding study.

    PubMed

    Thea, Donald M; Vwalika, Cheswa; Kasonde, Prisca; Kankasa, Chipepo; Sinkala, Moses; Semrau, Katherine; Shutes, Erin; Ayash, Christine; Tsai, Wei-Yann; Aldrovandi, Grace; Kuhn, Louise

    2004-08-01

    We present the rationale and design of the Zambian Exclusive Breast-feeding Study (ZEBS), a randomized trial evaluating the efficacy of short-duration exclusive breast-feeding (EBF) as a strategy to reduce postnatal human immunodeficiency virus (HIV) transmission while preserving the other health benefits of this important mode of infant feeding. One thousand two hundred HIV-positive pregnant women were recruited in Lusaka, Zambia, and followed with their infants for 24 months. In addition to Nevirapine (NVP), all women received intensive and frequent clinic- and home-based counseling to support exclusive breast-feeding. When the infant was 1 week of age, half of the women were randomly assigned to a group encouraged to abruptly (<24 h) cease all breast-feeding at 4 months. The primary outcome of the experimental (randomized) comparison is HIV-free survival at 24 months. The design is also observational and will compare HIV transmission rates between those who do and do not adhere to the counseling intervention promoting exclusive breast-feeding. Our study aims to quantify the benefit-risk ratio of early cessation of exclusive breast-feeding to interrupt mother-to-child transmission of HIV with an intensive behavioral intervention and has both observational and experimental analytic approaches. Our study design assesses efficacy and also has a prominent applied component that if the intervention is effective, it will permit rapid and sustainable adoption within low-resource communities.

  18. Comparative efficacy of two daily use mouthrinses: randomized clinical trial using an experimental gingivitis model.

    PubMed

    Charles, Christine Ann; McGuire, James Anthony; Sharma, Naresh Chandra; Qaqish, James

    2011-01-01

    Two antimicrobial agents, a fixed combination of essential oils (EOs) and 0.07% cetylpyridinium chloride (CPC) are found in commercially available mouthrinses, Listerine® Antiseptic and Crest® Pro HealthTM, respectively. Both mouthrinses have been shown to control dental plaque and gingivitis in short and longer term studies. The aim of this study was to determine the comparative effectiveness of these two mouthrinses using a 2-week experimental gingivitis model. Qualified subjects were randomly assigned to one of three mouthrinse groups: a fixed combination of EOs, 0.07% CPC, or negative control (C) rinse. Following baseline clinical assessments and a dental prophylaxis, subjects began a two-week period in which they rinsed twice daily with their assigned rinse and abstained from any mechanical oral hygiene procedures or other oral care products. Subjects were reassessed at the end of the two-week period. One hundred and forty-seven subjects were randomized and 142 completed this study. After two weeks use, the EOs rinse was superior (p < 0.011) to the CPC rinse in inhibiting the development of gingivitis, plaque, and bleeding, with 9.4% and 6.6% reductions compared to CPC for gingivitis and plaque, respectively. Both rinses were superior to the negative control rinse (p < 0.001). This study demonstrates that the essential oil-containing mouthrinse has superior antiplaque/antigingivitis effectiveness compared to the 0.07% CPC-containing mouthrinse without mechanical oral hygiene influence.

  19. An efficient randomized algorithm for contact-based NMR backbone resonance assignment.

    PubMed

    Kamisetty, Hetunandan; Bailey-Kellogg, Chris; Pandurangan, Gopal

    2006-01-15

    Backbone resonance assignment is a critical bottleneck in studies of protein structure, dynamics and interactions by nuclear magnetic resonance (NMR) spectroscopy. A minimalist approach to assignment, which we call 'contact-based', seeks to dramatically reduce experimental time and expense by replacing the standard suite of through-bond experiments with the through-space (nuclear Overhauser enhancement spectroscopy, NOESY) experiment. In the contact-based approach, spectral data are represented in a graph with vertices for putative residues (of unknown relation to the primary sequence) and edges for hypothesized NOESY interactions, such that observed spectral peaks could be explained if the residues were 'close enough'. Due to experimental ambiguity, several incorrect edges can be hypothesized for each spectral peak. An assignment is derived by identifying consistent patterns of edges (e.g. for alpha-helices and beta-sheets) within a graph and by mapping the vertices to the primary sequence. The key algorithmic challenge is to be able to uncover these patterns even when they are obscured by significant noise. This paper develops, analyzes and applies a novel algorithm for the identification of polytopes representing consistent patterns of edges in a corrupted NOESY graph. Our randomized algorithm aggregates simplices into polytopes and fixes inconsistencies with simple local modifications, called rotations, that maintain most of the structure already uncovered. In characterizing the effects of experimental noise, we employ an NMR-specific random graph model in proving that our algorithm gives optimal performance in expected polynomial time, even when the input graph is significantly corrupted. We confirm this analysis in simulation studies with graphs corrupted by up to 500% noise. Finally, we demonstrate the practical application of the algorithm on several experimental beta-sheet datasets. Our approach is able to eliminate a large majority of noise edges and to uncover large consistent sets of interactions. Our algorithm has been implemented in the platform-independent Python code. The software can be freely obtained for academic use by request from the authors.

  20. Effect of facet joint injection versus systemic steroids in low back pain: a randomized controlled trial.

    PubMed

    Ribeiro, Luiza Helena; Furtado, Rita Nely Vilar; Konai, Monique Sayuri; Andreo, Ana Beatriz; Rosenfeld, Andre; Natour, Jamil

    2013-11-01

    Randomized clinical trial. To compare the effectiveness of facet joint injection versus systemic steroid in patients with a diagnosis of facet joint syndrome. The term facet joint syndrome has been used to define back pain originating from the facet joints. Treatment is mainly conservative, although interventions, including intra-articular injections and medial branch nerve blocks are used to manage facet-mediated pain. Several studies have evaluated the effectiveness of these interventions. Results of facet joint injection, however, are conflicting. Sixty subjects with a diagnosis of facet joint syndrome were enrolled in the study. They were randomized into experimental and control groups. The experimental group was administered with intra-articular injection of 6 lumbar facet joints with triamcinolone hexacetonide; the control group was administered with triamcinolone acetonide intramuscular injection of 6 lumbar paravertebral points. Visits were taken at baseline and at 1, 4, 12, and 24 weeks after interventions. Outcome measures were used: pain visual analogue scale, pain visual analogue scale during extension of the spine, Likert scale, improvement percentage scale, Roland-Morris, 36-Item Short Form Health Survey, and accountability of medications taken.Homogeneity was tested using the Student t, Pearson χ, and Mann-Whitney tests. Analysis of variance was used to analyze differences in the groups over time and the Student t test to analyze differences between groups at each time evaluation. The groups were similar at baseline. Comparisons between the groups showed, in analysis of variance analysis, an improvement in the experimental group regarding diclofenac intake and quality of life, in the "role physical" profile, assessed by 36-Item Short Form Health Survey.In the analysis at each time point, an improvement in the experimental group was also found in the Roland-Morris questionnaire, in the improvement percentage scale and in the response to treatment, assessed by the Likert scale. Both treatments were effective, with a slight superiority of the intra-articular injection of steroids over intramuscular injection.

  1. Evaluation of a randomized controlled trial in the management of chronic lower back pain in a French automotive industry: an observational study.

    PubMed

    Nassif, Hala; Brosset, Nicolas; Guillaume, Marion; Delore-Milles, Emilie; Tafflet, Muriel; Buchholz, Frédéric; Toussaint, Jean-François

    2011-12-01

    To evaluate a specific workplace intervention for the management of chronic lower back pain among employees working in assembly positions in the automotive industry. Randomized controlled trial. On site at the workplace of a French automotive manufacturer. Subjects (N=75 volunteers) were recruited on site and randomly assigned to either an experimental group (n=37) or a control group (n=38). The experimental group followed a supervised 60-minute session, 3 times per week, of muscle strengthening, flexibility, and endurance training during 2 months. The control group received no direct intervention. Evaluation took place at baseline, 2 months, and 6 months. Pain related parameters were evaluated using validated questionnaires and scales translated into French (Quebec Back Pain Disability Scale, Rolan Morris Disability Questionnaire, Dallas Pain Questionnaire, and the Tampa Scale for Kinesiophobia). Perceived pain intensity was evaluated using the numerical rating scale, and physical outcome measures were evaluated using specific indicators (flexibility, Biering-Sorensen Test, Shirado test). The multivariate analysis of variance, t test, and Wilcoxon signed-rank test were used for statistical analysis. We observed a significant beneficial effect (P<.025) for the experimental group at 2 and 6 months in pain parameters, specific flexibility, and in back functions, and a significant improvement at 6 months in the control group for the perceived pain intensity, anterior flexion, flexibility of quadriceps, and Dallas Pain Questionnaire's work recreational score. An increase in the practice of physical activity outside the workplace was noted in both groups at 2 months but persisted at 6 months for the experimental group. This study reinforces the multiple health benefits of physical activity and physical therapy modalities in the workplace by assisting individuals at risk who have chronic LBP. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  2. Predicting network modules of cell cycle regulators using relative protein abundance statistics.

    PubMed

    Oguz, Cihan; Watson, Layne T; Baumann, William T; Tyson, John J

    2017-02-28

    Parameter estimation in systems biology is typically done by enforcing experimental observations through an objective function as the parameter space of a model is explored by numerical simulations. Past studies have shown that one usually finds a set of "feasible" parameter vectors that fit the available experimental data equally well, and that these alternative vectors can make different predictions under novel experimental conditions. In this study, we characterize the feasible region of a complex model of the budding yeast cell cycle under a large set of discrete experimental constraints in order to test whether the statistical features of relative protein abundance predictions are influenced by the topology of the cell cycle regulatory network. Using differential evolution, we generate an ensemble of feasible parameter vectors that reproduce the phenotypes (viable or inviable) of wild-type yeast cells and 110 mutant strains. We use this ensemble to predict the phenotypes of 129 mutant strains for which experimental data is not available. We identify 86 novel mutants that are predicted to be viable and then rank the cell cycle proteins in terms of their contributions to cumulative variability of relative protein abundance predictions. Proteins involved in "regulation of cell size" and "regulation of G1/S transition" contribute most to predictive variability, whereas proteins involved in "positive regulation of transcription involved in exit from mitosis," "mitotic spindle assembly checkpoint" and "negative regulation of cyclin-dependent protein kinase by cyclin degradation" contribute the least. These results suggest that the statistics of these predictions may be generating patterns specific to individual network modules (START, S/G2/M, and EXIT). To test this hypothesis, we develop random forest models for predicting the network modules of cell cycle regulators using relative abundance statistics as model inputs. Predictive performance is assessed by the areas under receiver operating characteristics curves (AUC). Our models generate an AUC range of 0.83-0.87 as opposed to randomized models with AUC values around 0.50. By using differential evolution and random forest modeling, we show that the model prediction statistics generate distinct network module-specific patterns within the cell cycle network.

  3. ARTS: automated randomization of multiple traits for study design.

    PubMed

    Maienschein-Cline, Mark; Lei, Zhengdeng; Gardeux, Vincent; Abbasi, Taimur; Machado, Roberto F; Gordeuk, Victor; Desai, Ankit A; Saraf, Santosh; Bahroos, Neil; Lussier, Yves

    2014-06-01

    Collecting data from large studies on high-throughput platforms, such as microarray or next-generation sequencing, typically requires processing samples in batches. There are often systematic but unpredictable biases from batch-to-batch, so proper randomization of biologically relevant traits across batches is crucial for distinguishing true biological differences from experimental artifacts. When a large number of traits are biologically relevant, as is common for clinical studies of patients with varying sex, age, genotype and medical background, proper randomization can be extremely difficult to prepare by hand, especially because traits may affect biological inferences, such as differential expression, in a combinatorial manner. Here we present ARTS (automated randomization of multiple traits for study design), which aids researchers in study design by automatically optimizing batch assignment for any number of samples, any number of traits and any batch size. ARTS is implemented in Perl and is available at github.com/mmaiensc/ARTS. ARTS is also available in the Galaxy Tool Shed, and can be used at the Galaxy installation hosted by the UIC Center for Research Informatics (CRI) at galaxy.cri.uic.edu. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. True Randomness from Big Data.

    PubMed

    Papakonstantinou, Periklis A; Woodruff, David P; Yang, Guang

    2016-09-26

    Generating random bits is a difficult task, which is important for physical systems simulation, cryptography, and many applications that rely on high-quality random bits. Our contribution is to show how to generate provably random bits from uncertain events whose outcomes are routinely recorded in the form of massive data sets. These include scientific data sets, such as in astronomics, genomics, as well as data produced by individuals, such as internet search logs, sensor networks, and social network feeds. We view the generation of such data as the sampling process from a big source, which is a random variable of size at least a few gigabytes. Our view initiates the study of big sources in the randomness extraction literature. Previous approaches for big sources rely on statistical assumptions about the samples. We introduce a general method that provably extracts almost-uniform random bits from big sources and extensively validate it empirically on real data sets. The experimental findings indicate that our method is efficient enough to handle large enough sources, while previous extractor constructions are not efficient enough to be practical. Quality-wise, our method at least matches quantum randomness expanders and classical world empirical extractors as measured by standardized tests.

  5. True Randomness from Big Data

    NASA Astrophysics Data System (ADS)

    Papakonstantinou, Periklis A.; Woodruff, David P.; Yang, Guang

    2016-09-01

    Generating random bits is a difficult task, which is important for physical systems simulation, cryptography, and many applications that rely on high-quality random bits. Our contribution is to show how to generate provably random bits from uncertain events whose outcomes are routinely recorded in the form of massive data sets. These include scientific data sets, such as in astronomics, genomics, as well as data produced by individuals, such as internet search logs, sensor networks, and social network feeds. We view the generation of such data as the sampling process from a big source, which is a random variable of size at least a few gigabytes. Our view initiates the study of big sources in the randomness extraction literature. Previous approaches for big sources rely on statistical assumptions about the samples. We introduce a general method that provably extracts almost-uniform random bits from big sources and extensively validate it empirically on real data sets. The experimental findings indicate that our method is efficient enough to handle large enough sources, while previous extractor constructions are not efficient enough to be practical. Quality-wise, our method at least matches quantum randomness expanders and classical world empirical extractors as measured by standardized tests.

  6. True Randomness from Big Data

    PubMed Central

    Papakonstantinou, Periklis A.; Woodruff, David P.; Yang, Guang

    2016-01-01

    Generating random bits is a difficult task, which is important for physical systems simulation, cryptography, and many applications that rely on high-quality random bits. Our contribution is to show how to generate provably random bits from uncertain events whose outcomes are routinely recorded in the form of massive data sets. These include scientific data sets, such as in astronomics, genomics, as well as data produced by individuals, such as internet search logs, sensor networks, and social network feeds. We view the generation of such data as the sampling process from a big source, which is a random variable of size at least a few gigabytes. Our view initiates the study of big sources in the randomness extraction literature. Previous approaches for big sources rely on statistical assumptions about the samples. We introduce a general method that provably extracts almost-uniform random bits from big sources and extensively validate it empirically on real data sets. The experimental findings indicate that our method is efficient enough to handle large enough sources, while previous extractor constructions are not efficient enough to be practical. Quality-wise, our method at least matches quantum randomness expanders and classical world empirical extractors as measured by standardized tests. PMID:27666514

  7. Hypnosis and Local Anesthesia for Dental Pain Relief-Alternative or Adjunct Therapy?-A Randomized, Clinical-Experimental Crossover Study.

    PubMed

    Wolf, Thomas Gerhard; Wolf, Dominik; Callaway, Angelika; Below, Dagna; d'Hoedt, Bernd; Willershausen, Brita; Daubländer, Monika

    2016-01-01

    This prospective randomized clinical crossover trial was designed to compare hypnosis and local anesthesia for experimental dental pain relief. Pain thresholds of the dental pulp were determined. A targeted standardized pain stimulus was applied and rated on the Visual Analogue Scale (0-10). The pain threshold was lower under hypnosis (58.3 ± 17.3, p < .001), maximal (80.0) under local anesthesia. The pain stimulus was scored higher under hypnosis (3.9 ± 3.8) than with local anesthesia (0.0, p < .001). Local anesthesia was superior to hypnosis and is a safe and effective method for pain relief in dentistry. Hypnosis seems to produce similar effects observed under sedation. It can be used in addition to local anesthesia and in individual cases as an alternative for pain control in dentistry.

  8. Entropy factor for randomness quantification in neuronal data.

    PubMed

    Rajdl, K; Lansky, P; Kostal, L

    2017-11-01

    A novel measure of neural spike train randomness, an entropy factor, is proposed. It is based on the Shannon entropy of the number of spikes in a time window and can be seen as an analogy to the Fano factor. Theoretical properties of the new measure are studied for equilibrium renewal processes and further illustrated on gamma and inverse Gaussian probability distributions of interspike intervals. Finally, the entropy factor is evaluated from the experimental records of spontaneous activity in macaque primary visual cortex and compared to its theoretical behavior deduced for the renewal process models. Both theoretical and experimental results show substantial differences between the Fano and entropy factors. Rather paradoxically, an increase in the variability of spike count is often accompanied by an increase of its predictability, as evidenced by the entropy factor. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Roughness Effects on Fretting Fatigue

    NASA Astrophysics Data System (ADS)

    Yue, Tongyan; Abdel Wahab, Magd

    2017-05-01

    Fretting is a small oscillatory relative motion between two normal loaded contact surfaces. It may cause fretting fatigue, fretting wear and/or fretting corrosion damage depending on various fretting couples and working conditions. Fretting fatigue usually occurs at partial slip condition, and results in catastrophic failure at the stress levels below the fatigue limit of the material. Many parameters may affect fretting behaviour, including the applied normal load and displacement, material properties, roughness of the contact surfaces, frequency, etc. Since fretting damage is undesirable due to contacting, the effect of rough contact surfaces on fretting damage has been studied by many researchers. Experimental method on this topic is usually focusing on rough surface effects by finishing treatment and random rough surface effects in order to increase fretting fatigue life. However, most of numerical models on roughness are based on random surface. This paper reviewed both experimental and numerical methodology on the rough surface effects on fretting fatigue.

  10. Verifying Digital Components of Physical Systems: Experimental Evaluation of Test Quality

    NASA Astrophysics Data System (ADS)

    Laputenko, A. V.; López, J. E.; Yevtushenko, N. V.

    2018-03-01

    This paper continues the study of high quality test derivation for verifying digital components which are used in various physical systems; those are sensors, data transfer components, etc. We have used logic circuits b01-b010 of the package of ITC'99 benchmarks (Second Release) for experimental evaluation which as stated before, describe digital components of physical systems designed for various applications. Test sequences are derived for detecting the most known faults of the reference logic circuit using three different approaches to test derivation. Three widely used fault types such as stuck-at-faults, bridges, and faults which slightly modify the behavior of one gate are considered as possible faults of the reference behavior. The most interesting test sequences are short test sequences that can provide appropriate guarantees after testing, and thus, we experimentally study various approaches to the derivation of the so-called complete test suites which detect all fault types. In the first series of experiments, we compare two approaches for deriving complete test suites. In the first approach, a shortest test sequence is derived for testing each fault. In the second approach, a test sequence is pseudo-randomly generated by the use of an appropriate software for logic synthesis and verification (ABC system in our study) and thus, can be longer. However, after deleting sequences detecting the same set of faults, a test suite returned by the second approach is shorter. The latter underlines the fact that in many cases it is useless to spend `time and efforts' for deriving a shortest distinguishing sequence; it is better to use the test minimization afterwards. The performed experiments also show that the use of only randomly generated test sequences is not very efficient since such sequences do not detect all the faults of any type. After reaching the fault coverage around 70%, saturation is observed, and the fault coverage cannot be increased anymore. For deriving high quality short test suites, the approach that is the combination of randomly generated sequences together with sequences which are aimed to detect faults not detected by random tests, allows to reach the good fault coverage using shortest test sequences.

  11. Robot-assisted single-site compared with laparoscopic single-incision cholecystectomy for benign gallbladder disease: protocol for a randomized controlled trial.

    PubMed

    Grochola, Lukasz Filip; Soll, Christopher; Zehnder, Adrian; Wyss, Roland; Herzog, Pascal; Breitenstein, Stefan

    2017-02-09

    Recent advances in robotic technology suggest that the utilization of the da Vinci Single-Site™ platform for cholecystectomy is safe, feasible and results in a shorter learning curve compared to conventional single-incision laparoscopic cholecystectomy. Moreover, the robot-assisted technology has been shown to reduce the surgeon's stress load compared to standard single-incision laparoscopy in an experimental setup, suggesting an important advantage of the da Vinci platform. However, the above-mentioned observations are based solely on case series, case reports and experimental data, as high-quality clinical trials to demonstrate the benefits of the da Vinci Single-Site™ cholecystectomy have not been performed to date. This study addresses the question whether robot-assisted Single-Site™ cholecystectomy provides significant benefits over single-incision laparoscopic cholecystectomy in terms of surgeon's stress load, while matching the standards of the conventional single-incision approach with regard to peri- and postoperative outcomes. It is designed as a single centre, single-blinded randomized controlled trial, which compares both surgical approaches with the primary endpoint surgeon's physical and mental stress load at the time of surgery. In addition, the study aims to assess secondary endpoints such as operating time, conversion rates, additional trocar placement, intra-operative blood loss, length of hospital stay, costs of procedure, health-related quality of life, cosmesis and complications. Patients as well as ward staff are blinded until the 1 st postoperative year. Sample size calculation based on the results of a previously published experimental setup utilizing an estimated effect size of surgeon's comfort of 0.8 (power of 0.8, alpha-error level of 0.05, error margin of 10-15%) resulted in a number of 30 randomized patients per arm. The study is the first randomized controlled trial that compares the da Vinci Single Site™ platform to conventional laparoscopic approaches in cholecystectomy, one of the most frequently performed operations in general surgery. This trial is registered at clinicaltrials.gov (trial number: NCT02485392 ). Registered February 19, 2015.

  12. Critical side channel effects in random bit generation with multiple semiconductor lasers in a polarization-based quantum key distribution system.

    PubMed

    Ko, Heasin; Choi, Byung-Seok; Choe, Joong-Seon; Kim, Kap-Joong; Kim, Jong-Hoi; Youn, Chun Ju

    2017-08-21

    Most polarization-based BB84 quantum key distribution (QKD) systems utilize multiple lasers to generate one of four polarization quantum states randomly. However, random bit generation with multiple lasers can potentially open critical side channels that significantly endangers the security of QKD systems. In this paper, we show unnoticed side channels of temporal disparity and intensity fluctuation, which possibly exist in the operation of multiple semiconductor laser diodes. Experimental results show that the side channels can enormously degrade security performance of QKD systems. An important system issue for the improvement of quantum bit error rate (QBER) related with laser driving condition is further addressed with experimental results.

  13. A randomized clinical trial in subjects with dry mouth evaluating subjective perceptions of an experimental oral gel, an oral rinse and a mouth spray compared to water.

    PubMed

    Jose, Anto; Siddiqi, Muhammad; Cronin, Matthew; DiLauro, Thomas S; Bosma, Mary Lynn

    2016-02-01

    This multicenter, randomized, parallel group study analyzed the effectiveness of an experimental oral gel, a commercially available oral rinse and a commercially available mouth spray versus water alone at relieving self-reported symptoms of dry mouth over a 28-day home use treatment period. The effects of the study treatments on dry mouth-related quality of life (QoL) were also investigated. Eligible subjects were stratified by dry mouth severity (mild, moderate or severe) and randomized to receive one of the study treatments. Prior to first use they completed a questionnaire designed to assess their baseline dry mouth-related QoL. Following first use and on Day 8 (2 hours post-treatment only) and Day 29, subjects completed the modified Product Performance and Attributes Questionnaire (PPAQ) I at 0.5, 1, 2 and 4 hours post-treatment. Subjects further assessed treatment performance using the PPAQ II questionnaire on Days 8 and 29 and the dry mouth-related QoL questionnaire on Day 29. In 396 randomized subjects almost all comparisons of responses to PPAQ I, including those for the primary endpoint (response to PPAQ I Question 1 'Relieving the discomfort of dry mouth' after 2 hours on Day 29), were statistically significant in favor of active treatment groups versus water (P < 0.05). All comparisons of responses to PPAQ II on Days 8 and 29 were statistically significant in favor of active treatments versus water (P < 0.05). Moreover, nearly all comparisons for dry mouth-related QoL scores on Day 29 were statistically significant in favor of the active treatments versus water. All the dry mouth management strategies in this trial were well tolerated.

  14. Modeling Invasion Dynamics with Spatial Random-Fitness Due to Micro-Environment

    PubMed Central

    Manem, V. S. K.; Kaveh, K.; Kohandel, M.; Sivaloganathan, S.

    2015-01-01

    Numerous experimental studies have demonstrated that the microenvironment is a key regulator influencing the proliferative and migrative potentials of species. Spatial and temporal disturbances lead to adverse and hazardous microenvironments for cellular systems that is reflected in the phenotypic heterogeneity within the system. In this paper, we study the effect of microenvironment on the invasive capability of species, or mutants, on structured grids (in particular, square lattices) under the influence of site-dependent random proliferation in addition to a migration potential. We discuss both continuous and discrete fitness distributions. Our results suggest that the invasion probability is negatively correlated with the variance of fitness distribution of mutants (for both advantageous and neutral mutants) in the absence of migration of both types of cells. A similar behaviour is observed even in the presence of a random fitness distribution of host cells in the system with neutral fitness rate. In the case of a bimodal distribution, we observe zero invasion probability until the system reaches a (specific) proportion of advantageous phenotypes. Also, we find that the migrative potential amplifies the invasion probability as the variance of fitness of mutants increases in the system, which is the exact opposite in the absence of migration. Our computational framework captures the harsh microenvironmental conditions through quenched random fitness distributions and migration of cells, and our analysis shows that they play an important role in the invasion dynamics of several biological systems such as bacterial micro-habitats, epithelial dysplasia, and metastasis. We believe that our results may lead to more experimental studies, which can in turn provide further insights into the role and impact of heterogeneous environments on invasion dynamics. PMID:26509572

  15. Patient Acceptance of Sexual Orientation and Gender Identity Questions on Intake Forms in Outpatient Clinics: A Pragmatic Randomized Multisite Trial.

    PubMed

    Rullo, Jordan E; Foxen, Jilian L; Griffin, Joan M; Geske, Jennifer R; Gonzalez, Cesar A; Faubion, Stephanie S; van Ryn, Michelle

    2018-03-09

    To (1) test whether patient attitudes toward intake forms at three Midwestern outpatient clinics are significantly more negative among those who are asked to complete SOGI questions versus those who are not; and (2) gain an in-depth understanding of patient concerns about SOGI questions. Data were collected between 6/29/2015 and 2/29/2016 from new patients (N = 491) who presented at three outpatient clinics in a large academic medical center. This study was originally a quality improvement project, and later, institutional review board approval was obtained for secondary data analysis. Two-stage mixed-methods study. (1) Experimental: New patients at three sites were randomly assigned to complete either routine intake forms (control) or routine intake forms with SOGI questions (experimental); and (2) qualitative: interviews with patients who responded negatively to SOGI questions. There were no significant differences in patient attitudes between experimental and control groups (p > .05). Of those who received SOGI questions, only 3 percent reported being distressed, upset, or offended by the SOGI questions. Collection of SOGI data as a part of the routine clinical patient intake process is not distressing to 97 percent of patients who are heterosexual, cisgender, and older than 50 years. © Health Research and Educational Trust.

  16. Feasibility of a Cognitive Behavioral Intervention to Manage Fatigue in Individuals With Traumatic Brain Injury: A Pilot Study.

    PubMed

    Raina, Ketki D; Morse, Jennifer Q; Chisholm, Denise; Leibold, Mary Lou; Shen, Jennifer; Whyte, Ellen

    2016-01-01

    To evaluate the feasibility of conducting a randomized clinical trial of an Internet-based manualized intervention to teach individuals with traumatic brain injury to manage their fatigue. Community dwelling. Forty-one participants randomized to Maximizing Energy (MAX) intervention group (n = 20) and Health Education group (n = 21). The experimental group (MAX intervention) received an 8-week program that combined education and Problem-Solving Therapy to teach individuals to manage fatigue-related problems. The attention control group received health education. Primary outcome measures pertained to the feasibility of conducting the trial. Secondary outcomes were fatigue impact and fatigue severity assessed at baseline and postintervention. Of the 65 participants referred, 41 were enrolled (63% recruitment rate), of which 3 withdrew (92% retention rate). Participants in the experimental and control groups completed their homework 75% and 85% of the time, respectively, and were equally engaged in the sessions. Participants in the experimental group were able to learn and implement the MAX intervention steps. Effect sizes for all measures ranged from small (-0.17) to medium (-0.58) in favor of the intervention group. Findings from the study suggest that the MAX intervention is feasible to administer to individuals with post-traumatic brain injury fatigue.

  17. [Effect of inspiratory muscle training on muscle strength and quality of life in patients with chronic airflow limitation: a randomized controlled trial].

    PubMed

    Serón, P; Riedemann, P; Muñoz, S; Doussoulin, A; Villarroel, P; Cea, X

    2005-11-01

    Chronic airflow limitation (CAL) is a significant cause of illness and death. Inspiratory muscle training has been described as a technique for managing CAL. The aim of the present study was to evaluate the effectiveness of inspiratory muscle training on improving physiological and functional variables. Randomized controlled trial in which 35 patients with CAL were assigned to receive either an experimental (n=17) or control (n=18) intervention. The experimental intervention consisted of 2 months of inspiratory muscle training using a device that administered a resistive load of 40% of maximal static inspiratory mouth pressure (PImax). Inspiratory muscle strength, exercise tolerance, respiratory function, and quality of life were assessed. Significant improvement in inspiratory muscle strength was observed in the experimental training group (P=.02). All patients improved over time in both groups (P<.001). PImax increased by 8.9 cm H2O per month of training. Likewise, the health-related quality of life scores improved by 0.56 points. Use of a threshold loading device is effective for strengthening inspiratory muscles as measured by PImax after the first month of training in patients with CAL. The long-term effectiveness of such training and its impact on quality of life should be studied in a larger number of patients.

  18. Reduce chest pain using modified silicone fluted drain tube for chest drainage after video-assisted thoracic surgery (VATS) lung resection.

    PubMed

    Li, Xin; Hu, Bin; Miao, Jinbai; Li, Hui

    2016-02-01

    The aim of this study was to assess the feasibility, efficacy and safety of a modified silicone fluted drain tube after video-assisted thoracic surgery (VATS) lung resection. The prospective randomized study included 50 patients who underwent VATS lung resection between March 2015 and June 2015. Eligible patients were randomized into two groups: experimental group (using the silicone fluted drain tubes for chest drainage) and control group (using standard drain tubes for chest drainage). The volume and characteristics of drainage, postoperative (PO) pain scores and hospital stay were recorded. All patients received standard care during hospital admission. In accordance with the exit criteria, three patients were excluded from study. The remaining 47 patients included in the final analysis were divided into two groups: experiment group (N=24) and control group (N=23). There was no significant difference between the two groups in terms of age, sex, height, weight, clinical diagnosis and type of surgical procedure. There was a trend toward less PO pain in experimental group on postoperative day (POD) 1, with a statistically significant difference. Patients in experimental group had a reduced occurrence of fever [temperature (T) >37.4 °C] compared to the control group. The silicone fluted drain tube is feasible and safe and may relieve patient PO pain and reduce occurrence of fever without the added risk of PO complications.

  19. [Efficacy of cultural-appropriate health education on information, motivation and behavioral skills of fever management for children in new immigrant Vietnamese mothers].

    PubMed

    Hsu, Hsian-Chou; Chen, Su-Jun; Huang, Mei-Chih

    2012-12-01

    Fever is the most common symptom in pediatric healthcare. Providing parents with better information on childhood fever management can improve their cognition and home-care abilities. Vietnamese female spouse comprise the largest segment of women who have emigrated from Southeast Asia to Taiwan over the past two decades. After arrival to Taiwan, they have to encounter the events of pregnancy and being a mother. In health care services, language barriers and cultural issues are key healthcare-related barriers to the adaptation of these women to Taiwan society. This study assessed the efficacy of using Vietnamese-language fever management education materials in changing the fever management behaviors of Vietnamese mothers living in Taiwan. This experimental study used a randomly assigned, pre- and post-test approach. A snowball method was used to recruit Vietnamese women living in southern Taiwan with children under 6 years of age. Participants were randomly assigned to experimental (n = 31, Vietnamese-language fever management brochure + VCD) and comparison (n = 30, Chinese-language brochure + VCD) groups. Both groups achieved significantly improvement scores in (fever) information, attitudes, self-efficacy and skills, with improvements significantly higher in the experimental group than the comparison group. This study supports that fever management education presented in the recipient's primary language effectively improves recipient fever management knowledge, attitudes, skills, and self-efficacy.

  20. Investigation effect of oral chamomilla on sleep quality in elderly people in Isfahan: A randomized control trial.

    PubMed

    Abdullahzadeh, Mehrdad; Matourypour, Pegah; Naji, Sayed Ali

    2017-01-01

    Elderly people often suffer from sleep disorders. Chamomile due to the many health benefits such as sedation may be effective in improving sleep quality in elderly people. This study aimed to determine the effect of Matricaria chamomilla extract on sleep quality in elderly people admitted to nursing homes of Isfahan in 2014. The present study is a quasi-experimental clinical trial. The study population was 77 cases of elderly hospitalized in nursing homes. Participants were selected through random continuous sampling and divided into intervention and control groups. The intervention group received 400 mg oral capsules of chamomile twice daily, after lunch and after dinner for 4 weeks. The control group did not receive the intervention. Sleep quality in older adults before and after intervention were compared using the Pittsburgh Sleep Quality Index questionnaire. Data were analyzed using descriptive statistics and paired t - and independent t -tests, one-way analysis of variance and liner regression analysis, using SPSS software version 17. Before intervention, the mean score of sleep quality both experimental and control groups showed no significant difference ( P > 0.05). After intervention, the mean score of sleep quality was a significant difference between experimental and control groups ( P < 0.001). Oral administration of chamomile extract has sedative properties in sleep quality of hospitalized elderly patients in nursing homes. Therefore, it can be used in similar cases and nursing care.

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