Meditation smartphone application effects on prehypertensive adults' blood pressure: Dose-response feasibility trial

OBJECTIVE: Essential hypertension (EH) is the most common chronic disease in the United States and a major cause of morbidity and mortality. Lifestyle interventions (e.g., diet, exercise, stress management) to reduce blood pressure (BP) are often complex with varying effectiveness. Breathing awareness meditation (BAM) is a stress management strategy with encouraging effects on BP, though widespread dissemination is hampered by the lack of an easy-to-use methodology to train and monitor BAM practices. A smartphone application (Tension Tamer [TT]) that implements BAM and tracks adherence has shown promise in addressing these gaps. This 6-month dose-response feasibility trial evaluated effects of the app on BP to further optimize BAM user guidelines. METHODS: Sixty-four adults with prehypertension were randomized to complete TT-guided BAM sessions for 5-, 10-, or 15-min intervals twice daily over 6 months. Continuous heart rate readings derived from the phone's video camera via reflective photoplethysmography were used as feedback and as an index of time-stamped adherence. Outcomes (resting BP, HR) were collected at baseline, 1-, 3-, and 6-months. RESULTS: Mixed modeling results showed a significant time effect for systolic BP (SBP) with a dose-response effect at Months 3 and 6. Adherence declined over time and was lowest in the 15-min dose condition, though SBP reductions were maintained. Generally, adherence was negatively associated with dose as the study progressed. CONCLUSIONS: Smartphone-implemented BAM appears to reduce SBP and can be a low-cost method to reach large populations. (PsycINFO Database Recor

Comparative Effectiveness Research: Challenges for Medical Journals

Editors from a number of medical journals lay out principles for journals considering publication of Comparative Effectiveness Research (CER). In order to encourage dissemination of this editorial, this article is freely available in PLoS Medicine and will be also published in Medical Decision Making, Croatian Medical Journal, The Cochrane Library, Trials, The American Journal of Managed Care, and Journal of Clinical Epidemiology

Mixed integer programming in production planning with backlogging and setup carryover : modeling and algorithms

This paper proposes a mixed integer programming formulation for modeling the capacitated multi-level lot sizing problem with both backlogging and setup carryover. Based on the model formulation, a progressive time-oriented decomposition heuristic framework is then proposed, where improvement and construction heuristics are effectively combined, therefore efficiently avoiding the weaknesses associated with the one-time decisions made by other classical time-oriented decomposition algorithms. Computational results show that the proposed optimization framework provides competitive solutions within a reasonable time

Comparative Effectiveness Research: An Empirical Study of Trials Registered in ClinicalTrials.gov

Background The $1.1 billion investment in comparative effectiveness research will reshape the evidence-base supporting decisions about treatment effectiveness, safety, and cost. Defining the current prevalence and characteristics of comparative effectiveness (CE) research will enable future assessments of the impact of this program. Methods We conducted an observational study of clinical trials addressing priority research topics defined by the Institute of Medicine and conducted in the US between 2007 and 2010. Trials were identified in ClinicalTrials.gov. Main outcome measures were the prevalence of comparative effectiveness research, nature of comparators selected, funding sources, and impact of these factors on results. Results 231 (22.3%; 95% CI 19.8%–24.9%) studies were CE studies and 804 (77.7%; 95% CI, 75.1%–80.2%) were non-CE studies, with 379 (36.6%; 95% CI, 33.7%–39.6%) employing a placebo control and 425 (41.1%; 95% CI, 38.1%–44.1%) no control. The most common treatments examined in CE studies were drug interventions (37.2%), behavioral interventions (28.6%), and procedures (15.6%). Study findings were favorable for the experimental treatment in 34.8% of CE studies and greater than twice as many (78.6%) non-CE studies (P<0.001). CE studies were more likely to receive government funding (P = 0.003) and less likely to receive industry funding (P = 0.01), with 71.8% of CE studies primarily funded by a noncommercial source. The types of interventions studied differed based on funding source, with 95.4% of industry trials studying a drug or device. In addition, industry-funded CE studies were associated with the fewest pediatric subjects (P<0.001), the largest anticipated sample size (P<0.001), and the shortest study duration (P<0.001). Conclusions In this sample of studies examining high priority areas for CE research, less than a quarter are CE studies and the majority is supported by government and nonprofits. The low prevalence of CE research exists across CE studies with a broad array of interventions and characteristics.National Library of Medicine (U.S.) (5G08LM009778)National Institutes of Health (U.S.

Overestimating Outcome Rates: Statistical Estimation When Reliability Is Suboptimal

To demonstrate how failure to account for measurement error in an outcome (dependent) variable can lead to significant estimation errors and to illustrate ways to recognize and avoid these errors. Data Sources . Medical literature and simulation models. Study Design/Data Collection . Systematic review of the published and unpublished epidemiological literature on the rate of preventable hospital deaths and statistical simulation of potential estimation errors based on data from these studies. Principal Findings . Most estimates of the rate of preventable deaths in U.S. hospitals rely upon classifying cases using one to three physician reviewers (implicit review). Because this method has low to moderate reliability, estimates based on statistical methods that do not account for error in the measurement of a “preventable death” can result in significant overestimation. For example, relying on a majority rule rating with three reviewers per case (reliability ∼0.45 for the average of three reviewers) can result in a 50–100 percent overestimation compared with an estimate based upon a reliably measured outcome (e.g., by using 50 reviewers per case). However, there are statistical methods that account for measurement error that can produce much more accurate estimates of outcome rates without requiring a large number of measurements per case. Conclusion . The statistical principles discussed in this case study are critically important whenever one seeks to estimate the proportion of cases belonging to specific categories (such as estimating how many patients have inadequate blood pressure control or identifying high-cost or low-quality physicians). When the true outcome rate is low (<20 percent), using an outcome measure that has low-to-moderate reliability will generally result in substantially overestimating the proportion of the population having the outcome unless statistical methods that adjust for measurement error are used.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74896/1/j.1475-6773.2006.00661.x.pd

Determinants of online shopping among tertiary students in Ghana: An extended technology acceptance model

The increasing penetration rate of the internet and technology in the world is quickly promoting online shopping. This has been fueled by growing innovations in the telecommunication and financial sector in an attempt to depeen financial inclusion. Innovations such as mobile money payments systems by mobile telephony companies have contributed to the continuous growth in online shopping amidst and the new generation of consumers who desire richer experiences. This study sought to identify the determinants of online shopping behaviour among tertiary students through the lens of the Technology Acceptance Model (TAM). The study proposed a revised TAM that integrated perceived cost and perceived risk to investigate what determined students online shopping intention and actual use. The survey involved a sample of 580 undergraduate students. The statistical technique used was Structural Equation Modelling-Partial Least Squares (SEM-PLS). The results showed that effect of ease of use on usefulness was very significant as same has been predicted by the Technology Acceptance Model. Among the independent variables, perceived cost (PC) was found to be the most significant factor affecting actual use (AU) of online shopping among students, nonetheless, perceived cost (PC) had no significant effect on purchase intention (PI). Perceived risk (PR) had no significant effect on actual use (AU) however, had a significant effect on purchase intention (PI). The study recommends online sellers to make online shopping efficient and less costive with assured safety and security of transactions as well as the product itself. A set of shopping platform could even be created specifically to give discounts and other offers to students. It also recommends future studies to employ additional determining factors such as the type of product/service, convenience and personal/demographic and geographic factors as influential to students’ online purchasing behaviour. © 2019, © 2019 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license

Comparison of methods for the detection of biofilm production in coagulase-negative staphylococci

<p>Abstract</p> <p>Background</p> <p>The ability of biofilm formation seems to play an essential role in the virulence of coagulase-negative staphylococci (CNS). The most clearly characterized component of staphylococcal biofilms is the polysaccharide intercellular adhesin (PIA) encoded by the <it>icaADBC </it>operon. Biofilm production was studied in 80 coagulase-negative staphylococci (CNS) strains isolated from clinical specimens of newborns with infection hospitalized at the Neonatal Unit of the University Hospital, Faculty of Medicine of Botucatu, and in 20 isolates obtained from the nares of healthy individuals without signs of infection. The objective was to compare three phenotypic methods with the detection of the <it>icaA</it>, <it>icaD </it>and <it>icaC </it>genes by PCR.</p> <p>Findings</p> <p>Among the 100 CNS isolates studied, 82% tested positive by PCR, 82% by the tube test, 81% by the TCP assay, and 73% by the CRA method. Using PCR as a reference, the tube test showed the best correlation with detection of the <it>ica </it>genes, presenting high sensitivity and specificity.</p> <p>Conclusions</p> <p>The tube adherence test can be indicated for the routine detection of biofilm production in CNS because of its easy application and low cost and because it guarantees reliable results with excellent sensitivity and specificity.</p

A novel flexible model for lot sizing and scheduling with non-triangular, period overlapping and carryover setups in different machine configurations

© 2017, Springer Science+Business Media New York. This paper develops and tests an efficient mixed integer programming model for capacitated lot sizing and scheduling with non-triangular and sequence-dependent setup times and costs incorporating all necessary features of setup carryover and overlapping on different machine configurations. The model’s formulation is based on the asymmetric travelling salesman problem and allows multiple lots of a product within a period. The model conserves the setup state when no product is being processed over successive periods, allows starting a setup in a period and ending it in the next period, permits ending a setup in a period and starting production in the next period(s), and enforces a minimum lot size over multiple periods. This new comprehensive model thus relaxes all limitations of physical separation between the periods. The model is first developed for a single machine and then extended to other machine configurations, including parallel machines and flexible flow lines. Computational tests demonstrate the flexibility and comprehensiveness of the proposed models