Sample records for random sampling plan

  1. Final report : sampling plan for pavement condition ratings of secondary roads.

    DOT National Transportation Integrated Search

    1984-01-01

    The purpose of this project was to develop a random sampling plan for use in selecting segments of the secondary highway system for evaluation under the Department's PMS. The plan developed is described here. It is a simple, workable, random sampling...

  2. Determination of the influence of dispersion pattern of pesticide-resistant individuals on the reliability of resistance estimates using different sampling plans.

    PubMed

    Shah, R; Worner, S P; Chapman, R B

    2012-10-01

    Pesticide resistance monitoring includes resistance detection and subsequent documentation/ measurement. Resistance detection would require at least one (≥1) resistant individual(s) to be present in a sample to initiate management strategies. Resistance documentation, on the other hand, would attempt to get an estimate of the entire population (≥90%) of the resistant individuals. A computer simulation model was used to compare the efficiency of simple random and systematic sampling plans to detect resistant individuals and to document their frequencies when the resistant individuals were randomly or patchily distributed. A patchy dispersion pattern of resistant individuals influenced the sampling efficiency of systematic sampling plans while the efficiency of random sampling was independent of such patchiness. When resistant individuals were randomly distributed, sample sizes required to detect at least one resistant individual (resistance detection) with a probability of 0.95 were 300 (1%) and 50 (10% and 20%); whereas, when resistant individuals were patchily distributed, using systematic sampling, sample sizes required for such detection were 6000 (1%), 600 (10%) and 300 (20%). Sample sizes of 900 and 400 would be required to detect ≥90% of resistant individuals (resistance documentation) with a probability of 0.95 when resistant individuals were randomly dispersed and present at a frequency of 10% and 20%, respectively; whereas, when resistant individuals were patchily distributed, using systematic sampling, a sample size of 3000 and 1500, respectively, was necessary. Small sample sizes either underestimated or overestimated the resistance frequency. A simple random sampling plan is, therefore, recommended for insecticide resistance detection and subsequent documentation.

  3. Health plan auditing: 100-percent-of-claims vs. random-sample audits.

    PubMed

    Sillup, George P; Klimberg, Ronald K

    2011-01-01

    The objective of this study was to examine the relative efficacy of two different methodologies for auditing self-funded medical claim expenses: 100-percent-of-claims auditing versus random-sampling auditing. Multiple data sets of claim errors or 'exceptions' from two Fortune-100 corporations were analysed and compared to 100 simulated audits of 300- and 400-claim random samples. Random-sample simulations failed to identify a significant number and amount of the errors that ranged from $200,000 to $750,000. These results suggest that health plan expenses of corporations could be significantly reduced if they audited 100% of claims and embraced a zero-defect approach.

  4. 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…

  5. [Krigle estimation and its simulated sampling of Chilo suppressalis population density].

    PubMed

    Yuan, Zheming; Bai, Lianyang; Wang, Kuiwu; Hu, Xiangyue

    2004-07-01

    In order to draw up a rational sampling plan for the larvae population of Chilo suppressalis, an original population and its two derivative populations, random population and sequence population, were sampled and compared with random sampling, gap-range-random sampling, and a new systematic sampling integrated Krigle interpolation and random original position. As for the original population whose distribution was up to aggregative and dependence range in line direction was 115 cm (6.9 units), gap-range-random sampling in line direction was more precise than random sampling. Distinguishing the population pattern correctly is the key to get a better precision. Gap-range-random sampling and random sampling are fit for aggregated population and random population, respectively, but both of them are difficult to apply in practice. Therefore, a new systematic sampling named as Krigle sample (n = 441) was developed to estimate the density of partial sample (partial estimation, n = 441) and population (overall estimation, N = 1500). As for original population, the estimated precision of Krigle sample to partial sample and population was better than that of investigation sample. With the increase of the aggregation intensity of population, Krigel sample was more effective than investigation sample in both partial estimation and overall estimation in the appropriate sampling gap according to the dependence range.

  6. Efficiency of analytical and sampling-based uncertainty propagation in intensity-modulated proton therapy

    NASA Astrophysics Data System (ADS)

    Wahl, N.; Hennig, P.; Wieser, H. P.; Bangert, M.

    2017-07-01

    The sensitivity of intensity-modulated proton therapy (IMPT) treatment plans to uncertainties can be quantified and mitigated with robust/min-max and stochastic/probabilistic treatment analysis and optimization techniques. Those methods usually rely on sparse random, importance, or worst-case sampling. Inevitably, this imposes a trade-off between computational speed and accuracy of the uncertainty propagation. Here, we investigate analytical probabilistic modeling (APM) as an alternative for uncertainty propagation and minimization in IMPT that does not rely on scenario sampling. APM propagates probability distributions over range and setup uncertainties via a Gaussian pencil-beam approximation into moments of the probability distributions over the resulting dose in closed form. It supports arbitrary correlation models and allows for efficient incorporation of fractionation effects regarding random and systematic errors. We evaluate the trade-off between run-time and accuracy of APM uncertainty computations on three patient datasets. Results are compared against reference computations facilitating importance and random sampling. Two approximation techniques to accelerate uncertainty propagation and minimization based on probabilistic treatment plan optimization are presented. Runtimes are measured on CPU and GPU platforms, dosimetric accuracy is quantified in comparison to a sampling-based benchmark (5000 random samples). APM accurately propagates range and setup uncertainties into dose uncertainties at competitive run-times (GPU ≤slant {5} min). The resulting standard deviation (expectation value) of dose show average global γ{3% / {3}~mm} pass rates between 94.2% and 99.9% (98.4% and 100.0%). All investigated importance sampling strategies provided less accuracy at higher run-times considering only a single fraction. Considering fractionation, APM uncertainty propagation and treatment plan optimization was proven to be possible at constant time complexity, while run-times of sampling-based computations are linear in the number of fractions. Using sum sampling within APM, uncertainty propagation can only be accelerated at the cost of reduced accuracy in variance calculations. For probabilistic plan optimization, we were able to approximate the necessary pre-computations within seconds, yielding treatment plans of similar quality as gained from exact uncertainty propagation. APM is suited to enhance the trade-off between speed and accuracy in uncertainty propagation and probabilistic treatment plan optimization, especially in the context of fractionation. This brings fully-fledged APM computations within reach of clinical application.

  7. Efficiency of analytical and sampling-based uncertainty propagation in intensity-modulated proton therapy.

    PubMed

    Wahl, N; Hennig, P; Wieser, H P; Bangert, M

    2017-06-26

    The sensitivity of intensity-modulated proton therapy (IMPT) treatment plans to uncertainties can be quantified and mitigated with robust/min-max and stochastic/probabilistic treatment analysis and optimization techniques. Those methods usually rely on sparse random, importance, or worst-case sampling. Inevitably, this imposes a trade-off between computational speed and accuracy of the uncertainty propagation. Here, we investigate analytical probabilistic modeling (APM) as an alternative for uncertainty propagation and minimization in IMPT that does not rely on scenario sampling. APM propagates probability distributions over range and setup uncertainties via a Gaussian pencil-beam approximation into moments of the probability distributions over the resulting dose in closed form. It supports arbitrary correlation models and allows for efficient incorporation of fractionation effects regarding random and systematic errors. We evaluate the trade-off between run-time and accuracy of APM uncertainty computations on three patient datasets. Results are compared against reference computations facilitating importance and random sampling. Two approximation techniques to accelerate uncertainty propagation and minimization based on probabilistic treatment plan optimization are presented. Runtimes are measured on CPU and GPU platforms, dosimetric accuracy is quantified in comparison to a sampling-based benchmark (5000 random samples). APM accurately propagates range and setup uncertainties into dose uncertainties at competitive run-times (GPU [Formula: see text] min). The resulting standard deviation (expectation value) of dose show average global [Formula: see text] pass rates between 94.2% and 99.9% (98.4% and 100.0%). All investigated importance sampling strategies provided less accuracy at higher run-times considering only a single fraction. Considering fractionation, APM uncertainty propagation and treatment plan optimization was proven to be possible at constant time complexity, while run-times of sampling-based computations are linear in the number of fractions. Using sum sampling within APM, uncertainty propagation can only be accelerated at the cost of reduced accuracy in variance calculations. For probabilistic plan optimization, we were able to approximate the necessary pre-computations within seconds, yielding treatment plans of similar quality as gained from exact uncertainty propagation. APM is suited to enhance the trade-off between speed and accuracy in uncertainty propagation and probabilistic treatment plan optimization, especially in the context of fractionation. This brings fully-fledged APM computations within reach of clinical application.

  8. Emperical Tests of Acceptance Sampling Plans

    NASA Technical Reports Server (NTRS)

    White, K. Preston, Jr.; Johnson, Kenneth L.

    2012-01-01

    Acceptance sampling is a quality control procedure applied as an alternative to 100% inspection. A random sample of items is drawn from a lot to determine the fraction of items which have a required quality characteristic. Both the number of items to be inspected and the criterion for determining conformance of the lot to the requirement are given by an appropriate sampling plan with specified risks of Type I and Type II sampling errors. In this paper, we present the results of empirical tests of the accuracy of selected sampling plans reported in the literature. These plans are for measureable quality characteristics which are known have either binomial, exponential, normal, gamma, Weibull, inverse Gaussian, or Poisson distributions. In the main, results support the accepted wisdom that variables acceptance plans are superior to attributes (binomial) acceptance plans, in the sense that these provide comparable protection against risks at reduced sampling cost. For the Gaussian and Weibull plans, however, there are ranges of the shape parameters for which the required sample sizes are in fact larger than the corresponding attributes plans, dramatically so for instances of large skew. Tests further confirm that the published inverse-Gaussian (IG) plan is flawed, as reported by White and Johnson (2011).

  9. Statistical design and analysis of environmental studies for plutonium and other transuranics at NAEG ''safety-shot'' sites

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

    Gilbert, R.O.; Eberhardt, L.L.; Fowler, E.B.

    This paper is centered around the use of stratified random sampling for estimating the total amount (inventory) of $sup 239-240$Pu and uranium in surface soil at ten ''safety-shot'' sites on the Nevada Test Site (NTS) and Tonopah Test Range (TTR) that are currently being studied by the Nevada Applied Ecology Group (NAEG). The use of stratified random sampling has resulted in estimates of inventory at these desert study sites that have smaller standard errors than would have been the case had simple random sampling (no stratification) been used. Estimates of inventory are given for $sup 235$U, $sup 238$U, and $supmore » 239-240$Pu in soil at A Site of Area 11 on the NTS. Other results presented include average concentrations of one or more of these isotopes in soil and vegetation and in soil profile samples at depths to 25 cm. The regression relationship between soil and vegetation concentrations of $sup 235$U and $sup 238$U at adjacent sampling locations is also examined using three different models. The applicability of stratified random sampling to the estimation of concentration contours of $sup 239-240$Pu in surface soil using computer algorithms is also investigated. Estimates of such contours are obtained using several different methods. The planning of field sampling plans for estimating inventory and distribution is discussed. (auth)« less

  10. Field substitution of nonresponders can maintain sample size and structure without altering survey estimates-the experience of the Italian behavioral risk factors surveillance system (PASSI).

    PubMed

    Baldissera, Sandro; Ferrante, Gianluigi; Quarchioni, Elisa; Minardi, Valentina; Possenti, Valentina; Carrozzi, Giuliano; Masocco, Maria; Salmaso, Stefania

    2014-04-01

    Field substitution of nonrespondents can be used to maintain the planned sample size and structure in surveys but may introduce additional bias. Sample weighting is suggested as the preferable alternative; however, limited empirical evidence exists comparing the two methods. We wanted to assess the impact of substitution on surveillance results using data from Progressi delle Aziende Sanitarie per la Salute in Italia-Progress by Local Health Units towards a Healthier Italy (PASSI). PASSI is conducted by Local Health Units (LHUs) through telephone interviews of stratified random samples of residents. Nonrespondents are replaced with substitutes randomly preselected in the same LHU stratum. We compared the weighted estimates obtained in the original PASSI sample (used as a reference) and in the substitutes' sample. The differences were evaluated using a Wald test. In 2011, 50,697 units were selected: 37,252 were from the original sample and 13,445 were substitutes; 37,162 persons were interviewed. The initially planned size and demographic composition were restored. No significant differences in the estimates between the original and the substitutes' sample were found. In our experience, field substitution is an acceptable method for dealing with nonresponse, maintaining the characteristics of the original sample without affecting the results. This evidence can support appropriate decisions about planning and implementing a surveillance system. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Human Capital Planning in Higher Education Institutions: A Strategic Human Resource Development Initiative in Jordan

    ERIC Educational Resources Information Center

    Khasawneh, Samer

    2011-01-01

    Purpose: The primary purpose of this study is to determine the status of human capital planning in higher education institutions in Jordan. Design/methodology/approach: A random sample of 120 faculty members (in administrative positions) responded to a human capital planning (HCP) survey. The survey consisted of a pool of 38 items distributed over…

  12. Sampling pig farms at the abattoir in a cross-sectional study - Evaluation of a sampling method.

    PubMed

    Birkegård, Anna Camilla; Halasa, Tariq; Toft, Nils

    2017-09-15

    A cross-sectional study design is relatively inexpensive, fast and easy to conduct when compared to other study designs. Careful planning is essential to obtaining a representative sample of the population, and the recommended approach is to use simple random sampling from an exhaustive list of units in the target population. This approach is rarely feasible in practice, and other sampling procedures must often be adopted. For example, when slaughter pigs are the target population, sampling the pigs on the slaughter line may be an alternative to on-site sampling at a list of farms. However, it is difficult to sample a large number of farms from an exact predefined list, due to the logistics and workflow of an abattoir. Therefore, it is necessary to have a systematic sampling procedure and to evaluate the obtained sample with respect to the study objective. We propose a method for 1) planning, 2) conducting, and 3) evaluating the representativeness and reproducibility of a cross-sectional study when simple random sampling is not possible. We used an example of a cross-sectional study with the aim of quantifying the association of antimicrobial resistance and antimicrobial consumption in Danish slaughter pigs. It was not possible to visit farms within the designated timeframe. Therefore, it was decided to use convenience sampling at the abattoir. Our approach was carried out in three steps: 1) planning: using data from meat inspection to plan at which abattoirs and how many farms to sample; 2) conducting: sampling was carried out at five abattoirs; 3) evaluation: representativeness was evaluated by comparing sampled and non-sampled farms, and the reproducibility of the study was assessed through simulated sampling based on meat inspection data from the period where the actual data collection was carried out. In the cross-sectional study samples were taken from 681 Danish pig farms, during five weeks from February to March 2015. The evaluation showed that the sampling procedure was reproducible with results comparable to the collected sample. However, the sampling procedure favoured sampling of large farms. Furthermore, both under-sampled and over-sampled areas were found using scan statistics. In conclusion, sampling conducted at abattoirs can provide a spatially representative sample. Hence it is a possible cost-effective alternative to simple random sampling. However, it is important to assess the properties of the resulting sample so that any potential selection bias can be addressed when reporting the findings. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Intraclass Correlation Values for Planning Group-Randomized Trials in Education

    ERIC Educational Resources Information Center

    Hedges, Larry V.; Hedberg, E. C.

    2007-01-01

    Experiments that assign intact groups to treatment conditions are increasingly common in social research. In educational research, the groups assigned are often schools. The design of group-randomized experiments requires knowledge of the intraclass correlation structure to compute statistical power and sample sizes required to achieve adequate…

  14. Statistical power and optimal design in experiments in which samples of participants respond to samples of stimuli.

    PubMed

    Westfall, Jacob; Kenny, David A; Judd, Charles M

    2014-10-01

    Researchers designing experiments in which a sample of participants responds to a sample of stimuli are faced with difficult questions about optimal study design. The conventional procedures of statistical power analysis fail to provide appropriate answers to these questions because they are based on statistical models in which stimuli are not assumed to be a source of random variation in the data, models that are inappropriate for experiments involving crossed random factors of participants and stimuli. In this article, we present new methods of power analysis for designs with crossed random factors, and we give detailed, practical guidance to psychology researchers planning experiments in which a sample of participants responds to a sample of stimuli. We extensively examine 5 commonly used experimental designs, describe how to estimate statistical power in each, and provide power analysis results based on a reasonable set of default parameter values. We then develop general conclusions and formulate rules of thumb concerning the optimal design of experiments in which a sample of participants responds to a sample of stimuli. We show that in crossed designs, statistical power typically does not approach unity as the number of participants goes to infinity but instead approaches a maximum attainable power value that is possibly small, depending on the stimulus sample. We also consider the statistical merits of designs involving multiple stimulus blocks. Finally, we provide a simple and flexible Web-based power application to aid researchers in planning studies with samples of stimuli.

  15. Validation of a sampling plan to generate food composition data.

    PubMed

    Sammán, N C; Gimenez, M A; Bassett, N; Lobo, M O; Marcoleri, M E

    2016-02-15

    A methodology to develop systematic plans for food sampling was proposed. Long life whole and skimmed milk, and sunflower oil were selected to validate the methodology in Argentina. Fatty acid profile in all foods, proximal composition, and calcium's content in milk were determined with AOAC methods. The number of samples (n) was calculated applying Cochran's formula with variation coefficients ⩽12% and an estimate error (r) maximum permissible ⩽5% for calcium content in milks and unsaturated fatty acids in oil. n were 9, 11 and 21 for long life whole and skimmed milk, and sunflower oil respectively. Sample units were randomly collected from production sites and sent to labs. Calculated r with experimental data was ⩽10%, indicating high accuracy in the determination of analyte content of greater variability and reliability of the proposed sampling plan. The methodology is an adequate and useful tool to develop sampling plans for food composition analysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Quality of life of coronary artery disease patients after the implementation of planning strategies for medication adherence 1

    PubMed Central

    Lourenço, Laura Bacelar de Araujo; Rodrigues, Roberta Cunha Matheus; São-João, Thaís Moreira; Gallani, Maria Cecilia; Cornélio, Marilia Estevam

    2015-01-01

    OBJECTIVE: to compare the general and specific health-related quality of life (HRQoL) between the Intervention (IG) and Control (CG) groups of coronary artery disease patients after the implementation of Action Planning and Coping Planning strategies for medication adherence and to verify the relationship between adherence and HRQoL. METHOD: this was a controlled and randomized study. RESULTS: the sample (n=115) was randomized into two groups, IG (n=59) and CG (n=56). Measures of medication adherence and general and specific HRQoL were obtained in the baseline and after two months of monitoring. CONCLUSION: the findings showed that the combination of intervention strategies - Action Planning and Coping Planning for medication adherence did not affect the HRQoL of coronary artery disease patients in outpatient monitoring. PMID:25806626

  17. Sample Size Estimation in Cluster Randomized Educational Trials: An Empirical Bayes Approach

    ERIC Educational Resources Information Center

    Rotondi, Michael A.; Donner, Allan

    2009-01-01

    The educational field has now accumulated an extensive literature reporting on values of the intraclass correlation coefficient, a parameter essential to determining the required size of a planned cluster randomized trial. We propose here a simple simulation-based approach including all relevant information that can facilitate this task. An…

  18. Cache-Aware Asymptotically-Optimal Sampling-Based Motion Planning

    PubMed Central

    Ichnowski, Jeffrey; Prins, Jan F.; Alterovitz, Ron

    2014-01-01

    We present CARRT* (Cache-Aware Rapidly Exploring Random Tree*), an asymptotically optimal sampling-based motion planner that significantly reduces motion planning computation time by effectively utilizing the cache memory hierarchy of modern central processing units (CPUs). CARRT* can account for the CPU’s cache size in a manner that keeps its working dataset in the cache. The motion planner progressively subdivides the robot’s configuration space into smaller regions as the number of configuration samples rises. By focusing configuration exploration in a region for periods of time, nearest neighbor searching is accelerated since the working dataset is small enough to fit in the cache. CARRT* also rewires the motion planning graph in a manner that complements the cache-aware subdivision strategy to more quickly refine the motion planning graph toward optimality. We demonstrate the performance benefit of our cache-aware motion planning approach for scenarios involving a point robot as well as the Rethink Robotics Baxter robot. PMID:25419474

  19. Cache-Aware Asymptotically-Optimal Sampling-Based Motion Planning.

    PubMed

    Ichnowski, Jeffrey; Prins, Jan F; Alterovitz, Ron

    2014-05-01

    We present CARRT* (Cache-Aware Rapidly Exploring Random Tree*), an asymptotically optimal sampling-based motion planner that significantly reduces motion planning computation time by effectively utilizing the cache memory hierarchy of modern central processing units (CPUs). CARRT* can account for the CPU's cache size in a manner that keeps its working dataset in the cache. The motion planner progressively subdivides the robot's configuration space into smaller regions as the number of configuration samples rises. By focusing configuration exploration in a region for periods of time, nearest neighbor searching is accelerated since the working dataset is small enough to fit in the cache. CARRT* also rewires the motion planning graph in a manner that complements the cache-aware subdivision strategy to more quickly refine the motion planning graph toward optimality. We demonstrate the performance benefit of our cache-aware motion planning approach for scenarios involving a point robot as well as the Rethink Robotics Baxter robot.

  20. Spatial Distribution and Sampling Plans for Grapevine Plant Canopy-Inhabiting Scaphoideus titanus (Hemiptera: Cicadellidae) Nymphs.

    PubMed

    Rigamonti, Ivo E; Brambilla, Carla; Colleoni, Emanuele; Jermini, Mauro; Trivellone, Valeria; Baumgärtner, Johann

    2016-04-01

    The paper deals with the study of the spatial distribution and the design of sampling plans for estimating nymph densities of the grape leafhopper Scaphoideus titanus Ball in vine plant canopies. In a reference vineyard sampled for model parameterization, leaf samples were repeatedly taken according to a multistage, stratified, random sampling procedure, and data were subjected to an ANOVA. There were no significant differences in density neither among the strata within the vineyard nor between the two strata with basal and apical leaves. The significant differences between densities on trunk and productive shoots led to the adoption of two-stage (leaves and plants) and three-stage (leaves, shoots, and plants) sampling plans for trunk shoots- and productive shoots-inhabiting individuals, respectively. The mean crowding to mean relationship used to analyze the nymphs spatial distribution revealed aggregated distributions. In both the enumerative and the sequential enumerative sampling plans, the number of leaves of trunk shoots, and of leaves and shoots of productive shoots, was kept constant while the number of plants varied. In additional vineyards data were collected and used to test the applicability of the distribution model and the sampling plans. The tests confirmed the applicability 1) of the mean crowding to mean regression model on the plant and leaf stages for representing trunk shoot-inhabiting distributions, and on the plant, shoot, and leaf stages for productive shoot-inhabiting nymphs, 2) of the enumerative sampling plan, and 3) of the sequential enumerative sampling plan. In general, sequential enumerative sampling was more cost efficient than enumerative sampling.

  1. Using known populations of pronghorn to evaluate sampling plans and estimators

    USGS Publications Warehouse

    Kraft, K.M.; Johnson, D.H.; Samuelson, J.M.; Allen, S.H.

    1995-01-01

    Although sampling plans and estimators of abundance have good theoretical properties, their performance in real situations is rarely assessed because true population sizes are unknown. We evaluated widely used sampling plans and estimators of population size on 3 known clustered distributions of pronghorn (Antilocapra americana). Our criteria were accuracy of the estimate, coverage of 95% confidence intervals, and cost. Sampling plans were combinations of sampling intensities (16, 33, and 50%), sample selection (simple random sampling without replacement, systematic sampling, and probability proportional to size sampling with replacement), and stratification. We paired sampling plans with suitable estimators (simple, ratio, and probability proportional to size). We used area of the sampling unit as the auxiliary variable for the ratio and probability proportional to size estimators. All estimators were nearly unbiased, but precision was generally low (overall mean coefficient of variation [CV] = 29). Coverage of 95% confidence intervals was only 89% because of the highly skewed distribution of the pronghorn counts and small sample sizes, especially with stratification. Stratification combined with accurate estimates of optimal stratum sample sizes increased precision, reducing the mean CV from 33 without stratification to 25 with stratification; costs increased 23%. Precise results (mean CV = 13) but poor confidence interval coverage (83%) were obtained with simple and ratio estimators when the allocation scheme included all sampling units in the stratum containing most pronghorn. Although areas of the sampling units varied, ratio estimators and probability proportional to size sampling did not increase precision, possibly because of the clumped distribution of pronghorn. Managers should be cautious in using sampling plans and estimators to estimate abundance of aggregated populations.

  2. Highlights of the national evaluation of the Forest Stewardship Planning Program

    Treesearch

    R.J. Moulton; J.D. Esseks

    2001-01-01

    In 1998 and 1999, a nationwide random sample of 1238 nonindustrial private (NIPF) landowners with approved multiple resource Forest Stewardship Plans were interviewed to determine if this program is meeting its Congressional mandate of promoting sustainable management of forest resources on NIPF ownerships. It was found that two-thirds of program participants had never...

  3. Enumerative and binomial sequential sampling plans for the multicolored Asian lady beetle (Coleoptera: Coccinellidae) in wine grapes.

    PubMed

    Galvan, T L; Burkness, E C; Hutchison, W D

    2007-06-01

    To develop a practical integrated pest management (IPM) system for the multicolored Asian lady beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), in wine grapes, we assessed the spatial distribution of H. axyridis and developed eight sampling plans to estimate adult density or infestation level in grape clusters. We used 49 data sets collected from commercial vineyards in 2004 and 2005, in Minnesota and Wisconsin. Enumerative plans were developed using two precision levels (0.10 and 0.25); the six binomial plans reflected six unique action thresholds (3, 7, 12, 18, 22, and 31% of cluster samples infested with at least one H. axyridis). The spatial distribution of H. axyridis in wine grapes was aggregated, independent of cultivar and year, but it was more randomly distributed as mean density declined. The average sample number (ASN) for each sampling plan was determined using resampling software. For research purposes, an enumerative plan with a precision level of 0.10 (SE/X) resulted in a mean ASN of 546 clusters. For IPM applications, the enumerative plan with a precision level of 0.25 resulted in a mean ASN of 180 clusters. In contrast, the binomial plans resulted in much lower ASNs and provided high probabilities of arriving at correct "treat or no-treat" decisions, making these plans more efficient for IPM applications. For a tally threshold of one adult per cluster, the operating characteristic curves for the six action thresholds provided binomial sequential sampling plans with mean ASNs of only 19-26 clusters, and probabilities of making correct decisions between 83 and 96%. The benefits of the binomial sampling plans are discussed within the context of improving IPM programs for wine grapes.

  4. Randomized algorithms for high quality treatment planning in volumetric modulated arc therapy

    NASA Astrophysics Data System (ADS)

    Yang, Yu; Dong, Bin; Wen, Zaiwen

    2017-02-01

    In recent years, volumetric modulated arc therapy (VMAT) has been becoming a more and more important radiation technique widely used in clinical application for cancer treatment. One of the key problems in VMAT is treatment plan optimization, which is complicated due to the constraints imposed by the involved equipments. In this paper, we consider a model with four major constraints: the bound on the beam intensity, an upper bound on the rate of the change of the beam intensity, the moving speed of leaves of the multi-leaf collimator (MLC) and its directional-convexity. We solve the model by a two-stage algorithm: performing minimization with respect to the shapes of the aperture and the beam intensities alternatively. Specifically, the shapes of the aperture are obtained by a greedy algorithm whose performance is enhanced by random sampling in the leaf pairs with a decremental rate. The beam intensity is optimized using a gradient projection method with non-monotonic line search. We further improve the proposed algorithm by an incremental random importance sampling of the voxels to reduce the computational cost of the energy functional. Numerical simulations on two clinical cancer date sets demonstrate that our method is highly competitive to the state-of-the-art algorithms in terms of both computational time and quality of treatment planning.

  5. A Study on Chocolate Consumption in Prospective Teachers

    ERIC Educational Resources Information Center

    Ozgen, Leyla

    2016-01-01

    This study was planned and conducted to determine the chocolate consumption habits of prospective teachers. The study population was comprised of students attending the Faculty of Education at Gazi University in Ankara and the sample consisted of 251 prospective teachers selected with simple random sampling. 96.4% and 3.6% of the prospective…

  6. Development of Effective Teacher Program: Teamwork Building Program for Thailand's Municipal Schools

    ERIC Educational Resources Information Center

    Chantathai, Pimpka; Tesaputa, Kowat; Somprach, Kanokorn

    2015-01-01

    This research is aimed to formulate the effective teacher teamwork program in municipal schools in Thailand. Primary survey on current situation and problem was conducted to develop the plan to suggest potential programs. Samples were randomly selected from municipal schools by using multi-stage sampling method in order to investigate their…

  7. Theory of Planned Behavior: Sensitivity and Specificity in Predicting Graduation and Drop-Out among College and University Students?

    ERIC Educational Resources Information Center

    Fichten, Catherine S.; Amsel, Rhonda; Jorgensen, Mary; Nguyen, Mai Nhu; Budd, Jillian; King, Laura; Jorgensen, Shirley; Asuncion, Jennison

    2016-01-01

    We examined sensitivity and specificity when using the three theory of planned behavior (TPB) scales (Perceived Behavioral Control, Subjective Norms, Attitude) to predict graduation and drop-out in a longitudinal study of 252 college and university students with disabilities and in a separate cross-sectional study of a random sample of 1380…

  8. Sample size adjustments for varying cluster sizes in cluster randomized trials with binary outcomes analyzed with second-order PQL mixed logistic regression.

    PubMed

    Candel, Math J J M; Van Breukelen, Gerard J P

    2010-06-30

    Adjustments of sample size formulas are given for varying cluster sizes in cluster randomized trials with a binary outcome when testing the treatment effect with mixed effects logistic regression using second-order penalized quasi-likelihood estimation (PQL). Starting from first-order marginal quasi-likelihood (MQL) estimation of the treatment effect, the asymptotic relative efficiency of unequal versus equal cluster sizes is derived. A Monte Carlo simulation study shows this asymptotic relative efficiency to be rather accurate for realistic sample sizes, when employing second-order PQL. An approximate, simpler formula is presented to estimate the efficiency loss due to varying cluster sizes when planning a trial. In many cases sampling 14 per cent more clusters is sufficient to repair the efficiency loss due to varying cluster sizes. Since current closed-form formulas for sample size calculation are based on first-order MQL, planning a trial also requires a conversion factor to obtain the variance of the second-order PQL estimator. In a second Monte Carlo study, this conversion factor turned out to be 1.25 at most. (c) 2010 John Wiley & Sons, Ltd.

  9. Statistical modeling of interfractional tissue deformation and its application in radiation therapy planning

    NASA Astrophysics Data System (ADS)

    Vile, Douglas J.

    In radiation therapy, interfraction organ motion introduces a level of geometric uncertainty into the planning process. Plans, which are typically based upon a single instance of anatomy, must be robust against daily anatomical variations. For this problem, a model of the magnitude, direction, and likelihood of deformation is useful. In this thesis, principal component analysis (PCA) is used to statistically model the 3D organ motion for 19 prostate cancer patients, each with 8-13 fractional computed tomography (CT) images. Deformable image registration and the resultant displacement vector fields (DVFs) are used to quantify the interfraction systematic and random motion. By applying the PCA technique to the random DVFs, principal modes of random tissue deformation were determined for each patient, and a method for sampling synthetic random DVFs was developed. The PCA model was then extended to describe the principal modes of systematic and random organ motion for the population of patients. A leave-one-out study tested both the systematic and random motion model's ability to represent PCA training set DVFs. The random and systematic DVF PCA models allowed the reconstruction of these data with absolute mean errors between 0.5-0.9 mm and 1-2 mm, respectively. To the best of the author's knowledge, this study is the first successful effort to build a fully 3D statistical PCA model of systematic tissue deformation in a population of patients. By sampling synthetic systematic and random errors, organ occupancy maps were created for bony and prostate-centroid patient setup processes. By thresholding these maps, PCA-based planning target volume (PTV) was created and tested against conventional margin recipes (van Herk for bony alignment and 5 mm fixed [3 mm posterior] margin for centroid alignment) in a virtual clinical trial for low-risk prostate cancer. Deformably accumulated delivered dose served as a surrogate for clinical outcome. For the bony landmark setup subtrial, the PCA PTV significantly (p<0.05) reduced D30, D20, and D5 to bladder and D50 to rectum, while increasing rectal D20 and D5. For the centroid-aligned setup, the PCA PTV significantly reduced all bladder DVH metrics and trended to lower rectal toxicity metrics. All PTVs covered the prostate with the prescription dose.

  10. A sampling design framework for monitoring secretive marshbirds

    USGS Publications Warehouse

    Johnson, D.H.; Gibbs, J.P.; Herzog, M.; Lor, S.; Niemuth, N.D.; Ribic, C.A.; Seamans, M.; Shaffer, T.L.; Shriver, W.G.; Stehman, S.V.; Thompson, W.L.

    2009-01-01

    A framework for a sampling plan for monitoring marshbird populations in the contiguous 48 states is proposed here. The sampling universe is the breeding habitat (i.e. wetlands) potentially used by marshbirds. Selection protocols would be implemented within each of large geographical strata, such as Bird Conservation Regions. Site selection will be done using a two-stage cluster sample. Primary sampling units (PSUs) would be land areas, such as legal townships, and would be selected by a procedure such as systematic sampling. Secondary sampling units (SSUs) will be wetlands or portions of wetlands in the PSUs. SSUs will be selected by a randomized spatially balanced procedure. For analysis, the use of a variety of methods as a means of increasing confidence in conclusions that may be reached is encouraged. Additional effort will be required to work out details and implement the plan.

  11. An approach to pavement management in Virginia.

    DOT National Transportation Integrated Search

    1981-01-01

    The report summarizes the objectives and benefits of formal pavement management systems and outlines an approach believed by the author to be practical for Virginia. The management of Virginia interstate pavements and a proposed random-sampling plan ...

  12. A Method on Dynamic Path Planning for Robotic Manipulator Autonomous Obstacle Avoidance Based on an Improved RRT Algorithm.

    PubMed

    Wei, Kun; Ren, Bingyin

    2018-02-13

    In a future intelligent factory, a robotic manipulator must work efficiently and safely in a Human-Robot collaborative and dynamic unstructured environment. Autonomous path planning is the most important issue which must be resolved first in the process of improving robotic manipulator intelligence. Among the path-planning methods, the Rapidly Exploring Random Tree (RRT) algorithm based on random sampling has been widely applied in dynamic path planning for a high-dimensional robotic manipulator, especially in a complex environment because of its probability completeness, perfect expansion, and fast exploring speed over other planning methods. However, the existing RRT algorithm has a limitation in path planning for a robotic manipulator in a dynamic unstructured environment. Therefore, an autonomous obstacle avoidance dynamic path-planning method for a robotic manipulator based on an improved RRT algorithm, called Smoothly RRT (S-RRT), is proposed. This method that targets a directional node extends and can increase the sampling speed and efficiency of RRT dramatically. A path optimization strategy based on the maximum curvature constraint is presented to generate a smooth and curved continuous executable path for a robotic manipulator. Finally, the correctness, effectiveness, and practicability of the proposed method are demonstrated and validated via a MATLAB static simulation and a Robot Operating System (ROS) dynamic simulation environment as well as a real autonomous obstacle avoidance experiment in a dynamic unstructured environment for a robotic manipulator. The proposed method not only provides great practical engineering significance for a robotic manipulator's obstacle avoidance in an intelligent factory, but also theoretical reference value for other type of robots' path planning.

  13. Training Needs of Governmental Schools' Principals Hosting Kindergartens Classes: The Case for Jordan

    ERIC Educational Resources Information Center

    Ashraah, Mamdouh M.; Al-Olaimat, Ali M.; Takash, Hanan M.

    2015-01-01

    This study aimed at identifying the training needs of governmental schools' principals with kindergarten classes. The sample of the study consisted of a random sample of (62) female principal. The instrument of the study was developed by the researchers and included 60 items distributed on four domains (planning, organizing, guidance, and…

  14. Preventing smoking relapse via Web-based computer-tailored feedback: a randomized controlled trial.

    PubMed

    Elfeddali, Iman; Bolman, Catherine; Candel, Math J J M; Wiers, Reinout W; de Vries, Hein

    2012-08-20

    Web-based computer-tailored approaches have the potential to be successful in supporting smoking cessation. However, the potential effects of such approaches for relapse prevention and the value of incorporating action planning strategies to effectively prevent smoking relapse have not been fully explored. The Stay Quit for You (SQ4U) study compared two Web-based computer-tailored smoking relapse prevention programs with different types of planning strategies versus a control group. To assess the efficacy of two Web-based computer-tailored programs in preventing smoking relapse compared with a control group. The action planning (AP) program provided tailored feedback at baseline and invited respondents to do 6 preparatory and coping planning assignments (the first 3 assignments prior to quit date and the final 3 assignments after quit date). The action planning plus (AP+) program was an extended version of the AP program that also provided tailored feedback at 11 time points after the quit attempt. Respondents in the control group only filled out questionnaires. The study also assessed possible dose-response relationships between abstinence and adherence to the programs. The study was a randomized controlled trial with three conditions: the control group, the AP program, and the AP+ program. Respondents were daily smokers (N = 2031), aged 18 to 65 years, who were motivated and willing to quit smoking within 1 month. The primary outcome was self-reported continued abstinence 12 months after baseline. Logistic regression analyses were conducted using three samples: (1) all respondents as randomly assigned, (2) a modified sample that excluded respondents who did not make a quit attempt in conformance with the program protocol, and (3) a minimum dose sample that also excluded respondents who did not adhere to at least one of the intervention elements. Observed case analyses and conservative analyses were conducted. In the observed case analysis of the randomized sample, abstinence rates were 22% (45/202) in the control group versus 33% (63/190) in the AP program and 31% (53/174) in the AP+ program. The AP program (odds ratio 1.95, P = .005) and the AP+ program (odds ratio 1.61, P = .049) were significantly more effective than the control condition. Abstinence rates and effects differed per sample. Finally, the results suggest a dose-response relationship between abstinence and the number of program elements completed by the respondents. Despite the differences in results caused by the variation in our analysis approaches, we can conclude that Web-based computer-tailored programs combined with planning strategy assignments and feedback after the quit attempt can be effective in preventing relapse 12 months after baseline. However, adherence to the intervention seems critical for effectiveness. Finally, our results also suggest that more research is needed to assess the optimum intervention dose. Dutch Trial Register: NTR1892; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1892 (Archived by WebCite at http://www.webcitation.org/693S6uuPM).

  15. DEFINED CONTRIBUTION PLANS, DEFINED BENEFIT PLANS, AND THE ACCUMULATION OF RETIREMENT WEALTH

    PubMed Central

    Poterba, James; Rauh, Joshua; Venti, Steven; Wise, David

    2010-01-01

    The private pension structure in the United States, once dominated by defined benefit (DB) plans, is currently divided between defined contribution (DC) and DB plans. Wealth accumulation in DC plans depends on the participant's contribution behavior and on financial market returns, while accumulation in DB plans is sensitive to a participant's labor market experience and to plan parameters. This paper simulates the distribution of retirement wealth under representative DB and DC plans. It uses data from the Health and Retirement Study (HRS) to explore how asset returns, earnings histories, and retirement plan characteristics contribute to the variation in retirement wealth outcomes. We simulate DC plan accumulation by randomly assigning individuals a share of wages that they and their employer contribute to the plan. We consider several possible asset allocation strategies, with asset returns drawn from the historical return distribution. Our DB plan simulations draw earnings histories from the HRS, and randomly assign each individual a pension plan drawn from a sample of large private and public defined benefit plans. The simulations yield distributions of both DC and DB wealth at retirement. Average retirement wealth accruals under current DC plans exceed average accruals under private sector DB plans, although DC plans are also more likely to generate very low retirement wealth outcomes. The comparison of current DC plans with more generous public sector DB plans is less definitive, because public sector DB plans are more generous on average than their private sector counterparts. PMID:21057597

  16. Factors in the Achievement of Below-Replacement Fertility in Chiang Mai, Thailand. Papers of the East-West Population Institute, Number 96, March 1986.

    ERIC Educational Resources Information Center

    Pardthaisong, Tieng

    The study assesses the impact of family planning programs on the fertility of women in the Chiang Mai province of Thailand, where family planning programs were introduced early in 1963. The study documents and estimates the fertility trend of Chiang Mai's population from existing sources of data. A demographic survey, in which a random sample of…

  17. Can Plan Recommendations Improve the Coverage Decisions of Vulnerable Populations in Health Insurance Marketplaces?

    PubMed

    Barnes, Andrew J; Hanoch, Yaniv; Rice, Thomas

    2016-01-01

    The Affordable Care Act's marketplaces present an important opportunity for expanding coverage but consumers face enormous challenges in navigating through enrollment and re-enrollment. We tested the effectiveness of a behaviorally informed policy tool--plan recommendations--in improving marketplace decisions. Data were gathered from a community sample of 656 lower-income, minority, rural residents of Virginia. We conducted an incentive-compatible, computer-based experiment using a hypothetical marketplace like the one consumers face in the federally-facilitated marketplaces, and examined their decision quality. Participants were randomly assigned to a control condition or three types of plan recommendations: social normative, physician, and government. For participants randomized to a plan recommendation condition, the plan that maximized expected earnings, and minimized total expected annual health care costs, was recommended. Primary data were gathered using an online choice experiment and questionnaire. Plan recommendations resulted in a 21 percentage point increase in the probability of choosing the earnings maximizing plan, after controlling for participant characteristics. Two conditions, government or providers recommending the lowest cost plan, resulted in plan choices that lowered annual costs compared to marketplaces where no recommendations were made. As millions of adults grapple with choosing plans in marketplaces and whether to switch plans during open enrollment, it is time to consider marketplace redesigns and leverage insights from the behavioral sciences to facilitate consumers' decisions.

  18. Applicability of action planning and coping planning to dental flossing among Norwegian adults: a confirmatory factor analysis approach.

    PubMed

    Astrøm, Anne Nordrehaug

    2008-06-01

    Using a prospective design and a representative sample of 25-yr-old Norwegians, this study hypothesized that action planning and coping planning will add to the prediction of flossing at 4 wk of follow-up over and above the effect of intention and previous flossing. This study tested the validity of a proposed 3-factor structure of the measurement model of intention, action planning, and coping planning and for its invariance across gender. A survey was conducted in three Norwegian counties, and 1,509 out of 8,000 randomly selected individuals completed questionnaires assessing the constructs of action planning and coping planning related to daily flossing. A random subsample of 500 participants was followed up at 4 wk with a telephone interview to assess flossing. Confirmatory factor analysis (CFA) confirmed the proposed 3-factor model after respecification. Although the chi-square test was statistically significant [chi(2) = 58.501, degrees of freedom (d.f.) = 17), complementary fit indices were satisfactory [goodness-of-fit index (GFI) = 0.99, root mean squared error of approximation (RMSEA) = 0.04]. Multigroup CFA provided evidence of complete invariance of the measurement model across gender. After controlling for previous flossing, intention (beta = 0.08) and action planning (beta = 0.11) emerged as independent predictors of subsequent flossing, accounting for 2.3% of its variance. Factorial validity of intention, action planning and coping planning, and the validity of action planning in predicting flossing prospectively, was confirmed by the present study.

  19. Can Plan Recommendations Improve the Coverage Decisions of Vulnerable Populations in Health Insurance Marketplaces?

    PubMed Central

    Barnes, Andrew J.; Hanoch, Yaniv; Rice, Thomas

    2016-01-01

    Objective The Affordable Care Act’s marketplaces present an important opportunity for expanding coverage but consumers face enormous challenges in navigating through enrollment and re-enrollment. We tested the effectiveness of a behaviorally informed policy tool—plan recommendations—in improving marketplace decisions. Study Setting Data were gathered from a community sample of 656 lower-income, minority, rural residents of Virginia. Study Design We conducted an incentive-compatible, computer-based experiment using a hypothetical marketplace like the one consumers face in the federally-facilitated marketplaces, and examined their decision quality. Participants were randomly assigned to a control condition or three types of plan recommendations: social normative, physician, and government. For participants randomized to a plan recommendation condition, the plan that maximized expected earnings, and minimized total expected annual health care costs, was recommended. Data Collection Primary data were gathered using an online choice experiment and questionnaire. Principal Findings Plan recommendations resulted in a 21 percentage point increase in the probability of choosing the earnings maximizing plan, after controlling for participant characteristics. Two conditions, government or providers recommending the lowest cost plan, resulted in plan choices that lowered annual costs compared to marketplaces where no recommendations were made. Conclusions As millions of adults grapple with choosing plans in marketplaces and whether to switch plans during open enrollment, it is time to consider marketplace redesigns and leverage insights from the behavioral sciences to facilitate consumers’ decisions. PMID:27028008

  20. Analyzing social experiments as implemented: A reexamination of the evidence from the HighScope Perry Preschool Program

    PubMed Central

    Heckman, James; Moon, Seong Hyeok; Pinto, Rodrigo; Savelyev, Peter; Yavitz, Adam

    2012-01-01

    Social experiments are powerful sources of information about the effectiveness of interventions. In practice, initial randomization plans are almost always compromised. Multiple hypotheses are frequently tested. “Significant” effects are often reported with p-values that do not account for preliminary screening from a large candidate pool of possible effects. This paper develops tools for analyzing data from experiments as they are actually implemented. We apply these tools to analyze the influential HighScope Perry Preschool Program. The Perry program was a social experiment that provided preschool education and home visits to disadvantaged children during their preschool years. It was evaluated by the method of random assignment. Both treatments and controls have been followed from age 3 through age 40. Previous analyses of the Perry data assume that the planned randomization protocol was implemented. In fact, as in many social experiments, the intended randomization protocol was compromised. Accounting for compromised randomization, multiple-hypothesis testing, and small sample sizes, we find statistically significant and economically important program effects for both males and females. We also examine the representativeness of the Perry study. PMID:23255883

  1. General statistical considerations

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

    Eberhardt, L L; Gilbert, R O

    From NAEG plutonium environmental studies program meeting; Las Vegas, Nevada, USA (2 Oct 1973). The high sampling variability encountered in environmental plutonium studies along with high analytical costs makes it very important that efficient soil sampling plans be used. However, efficient sampling depends on explicit and simple statements of the objectives of the study. When there are multiple objectives it may be difficult to devise a wholly suitable sampling scheme. Sampling for long-term changes in plutonium concentration in soils may also be complex and expensive. Further attention to problems associated with compositing samples is recommended, as is the consistent usemore » of random sampling as a basic technique. (auth)« less

  2. Kindergarten Teachers' Experience with Reporting Child Abuse in Taiwan

    ERIC Educational Resources Information Center

    Feng, Jui-Ying; Huang, Tzu-Yi; Wang, Chi-Jen

    2010-01-01

    Objective: The objectives were to examine factors associated with reporting child abuse among kindergarten teachers in Taiwan based on the Theory of Planned Behavior (TPB). Method: A stratified quota sampling technique was used to randomly select kindergarten teachers in Taiwan. The Child Abuse Intention Report Scale, which includes demographics,…

  3. Unbiased Estimates of Variance Components with Bootstrap Procedures

    ERIC Educational Resources Information Center

    Brennan, Robert L.

    2007-01-01

    This article provides general procedures for obtaining unbiased estimates of variance components for any random-model balanced design under any bootstrap sampling plan, with the focus on designs of the type typically used in generalizability theory. The results reported here are particularly helpful when the bootstrap is used to estimate standard…

  4. Drinking Plans and Drinking Outcomes: Examining Young Adults' Weekend Drinking Behavior

    ERIC Educational Resources Information Center

    Trim, Ryan S.; Clapp, John D.; Reed, Mark B.; Shillington, Audrey; Thombs, Dennis

    2011-01-01

    This study examined relationships among drinking intentions, environments, and outcomes in a random sample of 566 undergraduate college students. Telephone interviews were conducted with respondents before and after a single weekend assessing drinking intentions for the coming weekend related to subsequent drinking behaviors. Latent class analyses…

  5. Optimal Design for Two-Level Random Assignment and Regression Discontinuity Studies

    ERIC Educational Resources Information Center

    Rhoads, Christopher H.; Dye, Charles

    2016-01-01

    An important concern when planning research studies is to obtain maximum precision of an estimate of a treatment effect given a budget constraint. When research designs have a "multilevel" or "hierarchical" structure changes in sample size at different levels of the design will impact precision differently. Furthermore, there…

  6. Changes in the Precision of a Study from Planning Phase to Implementation Phase: Evidence from the First Wave of Group Randomized Trials Launched by the Institute of Education Sciences

    ERIC Educational Resources Information Center

    Spybrook, Jessaca; Lininger, Monica; Cullen, Anne

    2011-01-01

    The purpose of this study is to extend the work of Spybrook and Raudenbush (2009) and examine how the research designs and sample sizes changed from the planning phase to the implementation phase in the first wave of studies funded by IES. The authors examine the impact of the changes in terms of the changes in the precision of the study from the…

  7. The demand for health insurance coverage by low-income workers: can reduced premiums achieve full coverage?

    PubMed

    Chernew, M; Frick, K; McLaughlin, C G

    1997-10-01

    To assess the degree to which premium reductions will increase the participation in employer-sponsored health plans by low-income workers who are employed in small businesses. Sample of workers in small business (25 or fewer employees) in seven metropolitan areas. The data were gathered as part of the Small Business Benefits Survey, a telephone survey of small business conducted between October 1992 and February 1993. Probit regressions were used to estimate the demand for health insurance coverage by low-income workers. Predictions based on these findings were made to assess the extent to which premium reductions might increase coverage rates. Workers included in the sample were selected, at random, from a randomly generated set of firms drawn from Dun and Bradstreet's DMI (Dun's Market Inclusion). The response rate was 81 percent. Participation in employer-sponsored plans is high when coverage is offered. However, even when coverage is offered to employees who have no other source of insurance, participation is not universal. Although premium reductions will increase participation in employer-sponsored plans, even large subsidies will not induce all workers to participate in employer-sponsored plans. For workers eligible to participate, subsidies as high as 75 percent of premiums are estimated to increase participation rates from 89.0 percent to 92.6 percent. For workers in firms that do not sponsor plans, similar subsidies are projected to achieve only modest increases in coverage above that which would be observed if the workers had access to plans at unsubsidized, group market rates. Policies that rely on voluntary purchase of coverage to reduce the number of uninsured will have only modest success.

  8. A Fixed-Precision Sequential Sampling Plan for the Potato Tuberworm Moth, Phthorimaea operculella Zeller (Lepidoptera: Gelechidae), on Potato Cultivars.

    PubMed

    Shahbi, M; Rajabpour, A

    2017-08-01

    Phthorimaea operculella Zeller is an important pest of potato in Iran. Spatial distribution and fixed-precision sequential sampling for population estimation of the pest on two potato cultivars, Arinda ® and Sante ® , were studied in two separate potato fields during two growing seasons (2013-2014 and 2014-2015). Spatial distribution was investigated by Taylor's power law and Iwao's patchiness. Results showed that the spatial distribution of eggs and larvae was random. In contrast to Iwao's patchiness, Taylor's power law provided a highly significant relationship between variance and mean density. Therefore, fixed-precision sequential sampling plan was developed by Green's model at two precision levels of 0.25 and 0.1. The optimum sample size on Arinda ® and Sante ® cultivars at precision level of 0.25 ranged from 151 to 813 and 149 to 802 leaves, respectively. At 0.1 precision level, the sample sizes varied from 5083 to 1054 and 5100 to 1050 leaves for Arinda ® and Sante ® cultivars, respectively. Therefore, the optimum sample sizes for the cultivars, with different resistance levels, were not significantly different. According to the calculated stop lines, the sampling must be continued until cumulative number of eggs + larvae reached to 15-16 or 96-101 individuals at precision levels of 0.25 or 0.1, respectively. The performance of the sampling plan was validated by resampling analysis using resampling for validation of sampling plans software. The sampling plant provided in this study can be used to obtain a rapid estimate of the pest density with minimal effort.

  9. Differentially Constrained Motion Planning with State Lattice Motion Primitives

    DTIC Science & Technology

    2012-02-01

    datapoint distribution in such histograms to a scalar may be used . One example is Kullback - Leibler divergence; an even simpler method is a sum of ...the Coupled Layer Architecture for Robotic Autonomy (CLARAty) system at the Jet Propulsion Laboratory. This al- lowed us to test the application of ... good fit to extend the tree or the graph towards a random sample. However, by virtue of the regular structure of the state samples, lattice

  10. Motion planning for autonomous vehicle based on radial basis function neural network in unstructured environment.

    PubMed

    Chen, Jiajia; Zhao, Pan; Liang, Huawei; Mei, Tao

    2014-09-18

    The autonomous vehicle is an automated system equipped with features like environment perception, decision-making, motion planning, and control and execution technology. Navigating in an unstructured and complex environment is a huge challenge for autonomous vehicles, due to the irregular shape of road, the requirement of real-time planning, and the nonholonomic constraints of vehicle. This paper presents a motion planning method, based on the Radial Basis Function (RBF) neural network, to guide the autonomous vehicle in unstructured environments. The proposed algorithm extracts the drivable region from the perception grid map based on the global path, which is available in the road network. The sample points are randomly selected in the drivable region, and a gradient descent method is used to train the RBF network. The parameters of the motion-planning algorithm are verified through the simulation and experiment. It is observed that the proposed approach produces a flexible, smooth, and safe path that can fit any road shape. The method is implemented on autonomous vehicle and verified against many outdoor scenes; furthermore, a comparison of proposed method with the existing well-known Rapidly-exploring Random Tree (RRT) method is presented. The experimental results show that the proposed method is highly effective in planning the vehicle path and offers better motion quality.

  11. Motion Planning for Autonomous Vehicle Based on Radial Basis Function Neural Network in Unstructured Environment

    PubMed Central

    Chen, Jiajia; Zhao, Pan; Liang, Huawei; Mei, Tao

    2014-01-01

    The autonomous vehicle is an automated system equipped with features like environment perception, decision-making, motion planning, and control and execution technology. Navigating in an unstructured and complex environment is a huge challenge for autonomous vehicles, due to the irregular shape of road, the requirement of real-time planning, and the nonholonomic constraints of vehicle. This paper presents a motion planning method, based on the Radial Basis Function (RBF) neural network, to guide the autonomous vehicle in unstructured environments. The proposed algorithm extracts the drivable region from the perception grid map based on the global path, which is available in the road network. The sample points are randomly selected in the drivable region, and a gradient descent method is used to train the RBF network. The parameters of the motion-planning algorithm are verified through the simulation and experiment. It is observed that the proposed approach produces a flexible, smooth, and safe path that can fit any road shape. The method is implemented on autonomous vehicle and verified against many outdoor scenes; furthermore, a comparison of proposed method with the existing well-known Rapidly-exploring Random Tree (RRT) method is presented. The experimental results show that the proposed method is highly effective in planning the vehicle path and offers better motion quality. PMID:25237902

  12. Lot quality assurance sampling for screening communities hyperendemic for Schistosoma mansoni.

    PubMed

    Rabarijaona, L P; Boisier, P; Ravaoalimalala, V E; Jeanne, I; Roux, J F; Jutand, M A; Salamon, R

    2003-04-01

    Lot quality assurance sampling (LQAS) was evaluated for rapid low cost identification of communities where Schistosoma mansoni infection was hyperendemic in southern Madagascar. In the study area, S. mansoni infection shows very focused and heterogeneous distribution requiring multifariousness of local surveys. One sampling plan was tested in the field with schoolchildren and several others were simulated in the laboratory. Randomization and stool specimen collection were performed by voluntary teachers under direct supervision of the study staff and no significant problem occurred. As expected from Receiver Operating Characteristic (ROC) curves, all sampling plans allowed correct identification of hyperendemic communities and of most of the hypoendemic ones. Frequent misclassifications occurred for communities with intermediate prevalence and the cheapest plans had very low specificity. The study confirmed that LQAS would be a valuable tool for large scale screening in a country with scarce financial and staff resources. Involving teachers, appeared to be quite feasible and should not lower the reliability of surveys. We recommend that the national schistosomiasis control programme systematically uses LQAS for identification of communities, provided that sample sizes are adapted to the specific epidemiological patterns of S. mansoni infection in the main regions.

  13. Evaluation of behavior change goal-setting action plan on oral health activity and status.

    PubMed

    Lepore, Lindsay M; Yoon, Richard K; Chinn, Courtney H; Chussid, Steven

    2011-11-01

    This experimental study determined if a "report card-like" oral health action plan was effective in improving oral health behaviors in a sample of 69 patients, ages 1 to 6 years. Participants were divided randomly into control and intervention groups. Data collected included dmft, plaque score, Streptococcus mutans levels and oral health behaviors. Participants in the intervention group received an oral health action plan that included: 1. child's current caries-risk status; 2. identification issues of concern; and 3. one "goal" to improve on for the next visit. All participants returned after two months for follow-up examination and data collection.

  14. Psycho-Social Factors Causing Stress: A Study of Teacher Educators

    ERIC Educational Resources Information Center

    Jain, Geetika; Tyagi, Harish Kumar; Kumar, Anil

    2015-01-01

    Purpose: The present investigation was planned to determine the influence of type of personality, gender, age, qualification and experience causing stress among teacher educators at work. Method: A sample of 100 subjects from male and female teachers teaching in teacher training colleges, Delhi, India was drawn randomly. The data was collected by…

  15. Campus HIV Prevention Strategies: Planning for Success.

    ERIC Educational Resources Information Center

    Hoban, Mary T.; Ottenritter, Nan W.; Gascoigne, Jan L.; Kerr, Dianne L.

    This document presents the results of the National College Health Risk Behavior Survey (NCHRBS) conducted by the U.S. Centers for Disease Control (CDC) that pertain to HIV transmission. These results include sexual assault, alcohol and other drug use, and sexual behaviors. The survey was administered to a nationally representative random sample of…

  16. Job Demand in the Cosmetology Industry.

    ERIC Educational Resources Information Center

    Rudner, Lawrence M.; Deutermann, William V., Jr.

    In order to determine job demand in the cosmetology industry, a survey was made of a nationally representative stratified random sample of 1,454 beauty salons, barber shops, and unisex salons in July 1991. Salon owners were asked about 1990 and their plans for the future. Survey results were supplemented with information about the industry…

  17. An Employer Needs Assessment for Vocational Education.

    ERIC Educational Resources Information Center

    Muraski, Ed J.; Whiteman, Dick

    An employer needs assessment study was performed at Porterville College (PC), in California in 1991 as part of a comprehensive educational planning process for PC and the surrounding area. A validated survey instrument was sent to a stratified random sampling of 593 employers in the community, asking them to provide general information about their…

  18. The King Pre-Retirement Checklist: Assessing Differences in Pre-Retirement Planning.

    ERIC Educational Resources Information Center

    Zitzow, Darryl; King, Donald N.

    In an effort to assess the retirement preparedness of Midwestern populations above the age of 28, the King Pre-Retirement Checklist was administered to a sampling of 458 persons randomly selected and proportionally stratified by geographic location and community size. Factors examined were financial, social, family cohesion, mobility/health,…

  19. Determinants of customers' intention to participate in a Korean restaurant health promotion program: an application of the theory of planned behavior.

    PubMed

    Hong, Kyungeui; Gittelsohn, Joel; Joung, Hyojee

    2010-06-01

    The purpose of this study was to investigate the effects of personal characteristics and theory of planned behavior (TPB) constructs on the intention to participate in a restaurant health promotion program. In total, 830 adults residing in Seoul were sampled by a multi-stage cluster and random sampling design. Data were collected from a structured self-administered questionnaire, which covered variables concerning demographics, health status and TPB constructs including attitude, subjective norm and perceived behavioral control. A path analysis combining personal characteristics and TPB constructs was used to investigate determinants of the customers' intention. Positive and negative attitudes, subjective norms and perceived behavioral control directly affected the intention to participate. Demographics and health status both directly and indirectly affected the intention to participate. This study identifies personal characteristics and TPB constructs that are important to planning and implementing a restaurant health promotion program.

  20. Succession Planning and Financial Performance: Does Competition Matter?

    PubMed

    Patidar, Nitish; Gupta, Shivani; Azbik, Ginger; Weech-Maldonado, Robert

    2016-01-01

    Succession planning has been defined as the process by which one or more successors are identified for key positions, development activities are planned for identified successors, or both. Limited research exists pertaining to the relationship between hospital succession planning and financial performance, particularly in the context of market competition. We used the resource-based view framework to analyze the differential effect of succession planning on hospitals' financial performance based on market competition. According to RBV, organizations can achieve higher performance by using their superior resources and capabilities. We used a panel design consisting of a national sample of hospitals in the United States for 2006-2010. We analyzed data using multivariate linear regression with facility random effects and year and state fixed effects. The sample included 22,717 hospital-year observations; more than one half of the hospitals (55.4%) had a succession planning program. The study found a positive relationship between the presence of succession planning and financial performance (β = 1.41, p < .01), which was stronger in competitive markets (β = 2.31, p = .03) than in monopolistic markets (β = 1.06, p = .01). Hospitals can use these results to make informed decisions about investing in succession planning programs on the basis of competition in their market.

  1. Do mobile family planning clinics facilitate vasectomy use in Nepal?

    PubMed

    Padmadas, Sabu S; Amoako Johnson, Fiifi; Leone, Tiziana; Dahal, Govinda P

    2014-06-01

    Nepal has a distinct topography that makes reproductive health and family planning services difficult to access, particularly in remote mountain and hill regions where over a quarter of modern contraceptive users rely exclusively on vasectomy. A three-level random intercept logistic regression analysis was applied on data from the 2011 Nepal Demographic and Health Survey to investigate the extent of influence of mobile family planning clinics on the odds of a male or a female sterilization, adjusting for relevant characteristics including ecological differences and random effects. The analyses included a sample of 2014 sterilization users, considering responses from currently married women of reproductive ages. The odds of a male sterilization were significantly higher in a mobile clinic than those in a government hospital (odds ratio, 1.65; 95% confidence interval, 1.21-2.25). The effects remained unaltered and statistically significant after adjusting for sociodemographic and clustering effects. Random effects were highly significant, which suggest the extent of heterogeneity in vasectomy use at the community and district levels. The odds of vasectomy use in mobile clinics were significantly higher among couples residing in hill and mountain regions and among those with three or more sons or those with only daughters. Mobile clinics significantly increase the uptake of vasectomy in hard-to-reach areas of Nepal. Reproductive health interventions should consider mobile clinics as an effective strategy to improve access to male-based modern methods and enhance gender equity in family planning. Family planning interventions in hard-to-reach communities could consider mobile clinic as an effective strategy to promote male-based modern methods. Improving access to vasectomy could substantially reduce unmet need for family planning in countries experiencing rapid fertility transition. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Early Discharge and Home Care After Unplanned Cesarean Birth: Nursing Care Time

    PubMed Central

    Brooten, Dorothy; Knapp, Helen; Borucki, Lynne; Jacobsen, Barbara; Finkler, Steven; Arnold, Lauren; Mennuti, Michael

    2013-01-01

    Objective This study examined the mean nursing time spent providing discharge planning and home care to women who delivered by unplanned cesarean birth and examined differences in nursing time required by women with and without morbidity. Design A secondary analysis of nursing time from a randomized trial of transitional care (discharge planning and home follow-up) provided to women after cesarean delivery. Setting An urban tertiary-care hospital. Patients The sample (N = 61) of black and white women who had unplanned cesarean births and their full-term newborns was selected randomly. Forty-four percent of the women had experienced pregnancy complications. Interventions Advanced practice nurses provided discharge planning and 8-week home follow-up consisting of home visits, telephone outreach, and daily telephone availability. Outcome Measure Nursing time required was dictated by patient need and provider judgment rather than by reimbursement plan. Results More than half of the women required more than two home visits; mean home visit time was 1 hour. For women who experienced morbidity mean discharge planning time was 20 minutes more and mean home visit time 40 minutes more. Conclusions Current health care services that provide one or two 1-hour home visits to childbearing women at high risk may not be meeting the education and resource needs of this group. PMID:8892128

  3. Validation of Statistical Sampling Algorithms in Visual Sample Plan (VSP): Summary Report

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

    Nuffer, Lisa L; Sego, Landon H.; Wilson, John E.

    2009-02-18

    The U.S. Department of Homeland Security, Office of Technology Development (OTD) contracted with a set of U.S. Department of Energy national laboratories, including the Pacific Northwest National Laboratory (PNNL), to write a Remediation Guidance for Major Airports After a Chemical Attack. The report identifies key activities and issues that should be considered by a typical major airport following an incident involving release of a toxic chemical agent. Four experimental tasks were identified that would require further research in order to supplement the Remediation Guidance. One of the tasks, Task 4, OTD Chemical Remediation Statistical Sampling Design Validation, dealt with statisticalmore » sampling algorithm validation. This report documents the results of the sampling design validation conducted for Task 4. In 2005, the Government Accountability Office (GAO) performed a review of the past U.S. responses to Anthrax terrorist cases. Part of the motivation for this PNNL report was a major GAO finding that there was a lack of validated sampling strategies in the U.S. response to Anthrax cases. The report (GAO 2005) recommended that probability-based methods be used for sampling design in order to address confidence in the results, particularly when all sample results showed no remaining contamination. The GAO also expressed a desire that the methods be validated, which is the main purpose of this PNNL report. The objective of this study was to validate probability-based statistical sampling designs and the algorithms pertinent to within-building sampling that allow the user to prescribe or evaluate confidence levels of conclusions based on data collected as guided by the statistical sampling designs. Specifically, the designs found in the Visual Sample Plan (VSP) software were evaluated. VSP was used to calculate the number of samples and the sample location for a variety of sampling plans applied to an actual release site. Most of the sampling designs validated are probability based, meaning samples are located randomly (or on a randomly placed grid) so no bias enters into the placement of samples, and the number of samples is calculated such that IF the amount and spatial extent of contamination exceeds levels of concern, at least one of the samples would be taken from a contaminated area, at least X% of the time. Hence, "validation" of the statistical sampling algorithms is defined herein to mean ensuring that the "X%" (confidence) is actually met.« less

  4. People's Need for Additional Job Training: Development and Evaluation of an Assessment Procedure.

    ERIC Educational Resources Information Center

    Copa, George H.; Maurice, Clyde F.

    A procedure was developed and evaluated for assessing the self-perceived educational needs of people as one input to the process of planning, approving, and implementing relevant educational programs. The method of data collection involved selecting samples of people by randomly selecting households in a given geographic area, and then contacting…

  5. Vocational + Academic Integration: Preparing Texas Students for the Work Force. Evaluation Report.

    ERIC Educational Resources Information Center

    Texas State Council on Vocational Education, Austin.

    In a study of integration of vocational and academic education in Texas, administrators of a stratified random sample of 112 school districts in the state were surveyed, and 65% responded. Steps toward integration were being taken in 84% of the districts; however, only four districts have implemented integration plans described as comprehensive.…

  6. Pharmacists' Attitudes toward Continuing Education: Implications for Planning Curricular CE Programs.

    ERIC Educational Resources Information Center

    Hanson, Alan L.

    1989-01-01

    A random sample of 661 U.S. and Canadian pharmacists (38 percent response) identified characteristics of pharmacy continuing education (CE) program clientele that might assist in marketing these programs. Attitude toward CE was related to sex, age, practice setting, and source of CE. Practice setting was of most value in targeting a potential…

  7. Investigating the Relationship between Effective Communication of Spouse and Father-Child Relationship (Test Pattern Causes to Education Parents)

    ERIC Educational Resources Information Center

    Ataeifar, Robabeh; Amiri, Sholeh; Ali Nadi, Mohammad

    2016-01-01

    This research is targeted with the plan of father-child model or effective relationship mediating of spouses or investigating attachment style, personality traits, communication skills, and spouses' sexual satisfaction. Based on this, 260 people (father and child) were selected through random sampling method based on share. Participants were…

  8. School Counselor Advocacy for Lesbian, Gay, and Bisexual Students: Intentions and Practice

    ERIC Educational Resources Information Center

    Simons, Jack D.; Hutchison, Brian; Bahr, Michael W.

    2017-01-01

    This study sought to understand school counselor advocacy for lesbian, gay, and bisexual (LGB) students using the theory of planned behavior (Ajzen, 2015). The authors analyzed data from a non-random sample of 398 school counselors in the United States. Participants completed demographic items and the Attitudes subscale of the Sexual Orientation…

  9. Real-Time Motion Planning and Safe Navigation in Dynamic Multi-Robot Environments

    DTIC Science & Technology

    2006-12-15

    referee against a robot for pushing or hitting an opponent excessively, as well as for a non- goalie robot entering the team’s own defense area. The DSS... pulling ” a search graph by choosing random samples and then trying to connect a path to those points, some planners “push” samples by first choosing...implement the various roles (attacker, goalie , defender), which in turn build on sub-tactics known as skills [16]. One primitive skill used by almost all

  10. Testing how voluntary participation requirements in an environmental study affect the planned random sample design outcomes: implications for the predictions of values and their uncertainty.

    NASA Astrophysics Data System (ADS)

    Ander, Louise; Lark, Murray; Smedley, Pauline; Watts, Michael; Hamilton, Elliott; Fletcher, Tony; Crabbe, Helen; Close, Rebecca; Studden, Mike; Leonardi, Giovanni

    2015-04-01

    Random sampling design is optimal in order to be able to assess outcomes, such as the mean of a given variable across an area. However, this optimal sampling design may be compromised to an unknown extent by unavoidable real-world factors: the extent to which the study design can still be considered random, and the influence this may have on the choice of appropriate statistical data analysis is examined in this work. We take a study which relied on voluntary participation for the sampling of private water tap chemical composition in England, UK. This study was designed and implemented as a categorical, randomised study. The local geological classes were grouped into 10 types, which were considered to be most important in likely effects on groundwater chemistry (the source of all the tap waters sampled). Locations of the users of private water supplies were made available to the study group from the Local Authority in the area. These were then assigned, based on location, to geological groups 1 to 10 and randomised within each group. However, the permission to collect samples then required active, voluntary participation by householders and thus, unlike many environmental studies, could not always follow the initial sample design. Impediments to participation ranged from 'willing but not available' during the designated sampling period, to a lack of response to requests to sample (assumed to be wholly unwilling or unable to participate). Additionally, a small number of unplanned samples were collected via new participants making themselves known to the sampling teams, during the sampling period. Here we examine the impact this has on the 'random' nature of the resulting data distribution, by comparison with the non-participating known supplies. We consider the implications this has on choice of statistical analysis methods to predict values and uncertainty at un-sampled locations.

  11. Proof of impact and pipeline planning: directions and challenges for social audit in the health sector.

    PubMed

    Andersson, Neil

    2011-12-21

    Social audits are typically observational studies, combining qualitative and quantitative uptake of evidence with consultative interpretation of results. This often falters on issues of causality because their cross-sectional design limits interpretation of time relations and separation out of other indirect associations.Social audits drawing on methods of randomised controlled cluster trials (RCCT) allow more certainty about causality. Randomisation means that exposure occurs independently of all events that precede it--it converts potential confounders and other covariates into random differences. In 2008, CIET social audits introduced randomisation of the knowledge translation component with subsequent measurement of impact in the changes introduced. This "proof of impact" generates an additional layer of evidence in a cost-effective way, providing implementation-ready solutions for planners.Pipeline planning is a social audit that incorporates stepped wedge RCCTs. From a listing of districts/communities as a sampling frame, individual entities (communities, towns, districts) are randomly assigned to waves of intervention. Measurement of the impact takes advantage of the delay occasioned by the reality that there are insufficient resources to implement everywhere at the same time. The impact in the first wave contrasts with the second wave, which in turn contrasts with a third wave, and so on until all have received the intervention. Provided care is taken to achieve reasonable balance in the random allocation of communities, towns or districts to the waves, the resulting analysis can be straightforward.Where there is sufficient management interest in and commitment to evidence, pipeline planning can be integrated in the roll-out of programmes where real time information can improve the pipeline. Not all interventions can be randomly allocated, however, and random differences can still distort measurement. Other issues include contamination of the subsequent waves, ambiguity of indicators, "participant effects" that result from lack of blinding and lack of placebos, ethics and, not least important, the skills to do pipeline planning correctly.

  12. Proof of impact and pipeline planning: directions and challenges for social audit in the health sector

    PubMed Central

    2011-01-01

    Social audits are typically observational studies, combining qualitative and quantitative uptake of evidence with consultative interpretation of results. This often falters on issues of causality because their cross-sectional design limits interpretation of time relations and separation out of other indirect associations. Social audits drawing on methods of randomised controlled cluster trials (RCCT) allow more certainty about causality. Randomisation means that exposure occurs independently of all events that precede it – it converts potential confounders and other covariates into random differences. In 2008, CIET social audits introduced randomisation of the knowledge translation component with subsequent measurement of impact in the changes introduced. This “proof of impact” generates an additional layer of evidence in a cost-effective way, providing implementation-ready solutions for planners. Pipeline planning is a social audit that incorporates stepped wedge RCCTs. From a listing of districts/communities as a sampling frame, individual entities (communities, towns, districts) are randomly assigned to waves of intervention. Measurement of the impact takes advantage of the delay occasioned by the reality that there are insufficient resources to implement everywhere at the same time. The impact in the first wave contrasts with the second wave, which in turn contrasts with a third wave, and so on until all have received the intervention. Provided care is taken to achieve reasonable balance in the random allocation of communities, towns or districts to the waves, the resulting analysis can be straightforward. Where there is sufficient management interest in and commitment to evidence, pipeline planning can be integrated in the roll-out of programmes where real time information can improve the pipeline. Not all interventions can be randomly allocated, however, and random differences can still distort measurement. Other issues include contamination of the subsequent waves, ambiguity of indicators, “participant effects” that result from lack of blinding and lack of placebos, ethics and, not least important, the skills to do pipeline planning correctly. PMID:22376386

  13. Differences in reporting of analyses in internal company documents versus published trial reports: comparisons in industry-sponsored trials in off-label uses of gabapentin.

    PubMed

    Vedula, S Swaroop; Li, Tianjing; Dickersin, Kay

    2013-01-01

    Details about the type of analysis (e.g., intent to treat [ITT]) and definitions (i.e., criteria for including participants in the analysis) are necessary for interpreting a clinical trial's findings. Our objective was to compare the description of types of analyses and criteria for including participants in the publication (i.e., what was reported) with descriptions in the corresponding internal company documents (i.e., what was planned and what was done). Trials were for off-label uses of gabapentin sponsored by Pfizer and Parke-Davis, and documents were obtained through litigation. For each trial, we compared internal company documents (protocols, statistical analysis plans, and research reports, all unpublished), with publications. One author extracted data and another verified, with a third person verifying discordant items and a sample of the rest. Extracted data included the number of participants randomized and analyzed for efficacy, and types of analyses for efficacy and safety and their definitions (i.e., criteria for including participants in each type of analysis). We identified 21 trials, 11 of which were published randomized controlled trials, and that provided the documents needed for planned comparisons. For three trials, there was disagreement on the number of randomized participants between the research report and publication. Seven types of efficacy analyses were described in the protocols, statistical analysis plans, and publications, including ITT and six others. The protocol or publication described ITT using six different definitions, resulting in frequent disagreements between the two documents (i.e., different numbers of participants were included in the analyses). Descriptions of analyses conducted did not agree between internal company documents and what was publicly reported. Internal company documents provide extensive documentation of methods planned and used, and trial findings, and should be publicly accessible. Reporting standards for randomized controlled trials should recommend transparent descriptions and definitions of analyses performed and which study participants are excluded.

  14. An Asymptotically-Optimal Sampling-Based Algorithm for Bi-directional Motion Planning

    PubMed Central

    Starek, Joseph A.; Gomez, Javier V.; Schmerling, Edward; Janson, Lucas; Moreno, Luis; Pavone, Marco

    2015-01-01

    Bi-directional search is a widely used strategy to increase the success and convergence rates of sampling-based motion planning algorithms. Yet, few results are available that merge both bi-directional search and asymptotic optimality into existing optimal planners, such as PRM*, RRT*, and FMT*. The objective of this paper is to fill this gap. Specifically, this paper presents a bi-directional, sampling-based, asymptotically-optimal algorithm named Bi-directional FMT* (BFMT*) that extends the Fast Marching Tree (FMT*) algorithm to bidirectional search while preserving its key properties, chiefly lazy search and asymptotic optimality through convergence in probability. BFMT* performs a two-source, lazy dynamic programming recursion over a set of randomly-drawn samples, correspondingly generating two search trees: one in cost-to-come space from the initial configuration and another in cost-to-go space from the goal configuration. Numerical experiments illustrate the advantages of BFMT* over its unidirectional counterpart, as well as a number of other state-of-the-art planners. PMID:27004130

  15. [Identification of communities endemic for urinary bilharziosis by the "Lot Quality Assurance Sampling" method in Madagascar].

    PubMed

    Rabarijaona, L P; Andriamaroson, B J; Ravaoalimalala, V E; Ravoniarimbinina, P; Migliani, R

    2001-01-01

    Reduction of morbidity is the main component in the National Schistosomiasis Control Program in Madagascar. The lot quality assurance sampling (LQAS) method has previously been shown as a useful tool in assessment of immunization coverage. A study was carried in the western part of Madagascar aiming to evaluate the applicability of the method in measuring the level of Schistosoma haematobium endemic level in different communities. Parasitological examination of urine samples from 1,124 children aged 5 to 19 years from 12 different schools by use of filtration technique constituted the reference in determining the prevalence. Three schools were found hyper-endemic (prevalence more than 60%), 5 schools were intermediate-endemic (prevalence between 30 to 59%), and 4 were hypo-endemic (prevalence less than 30%). Those figures indicate a heterogeneous distribution of S. haematobium in the study area. A sampling plan (16.6) was then tested in the same area while other sampling plans were simulated in the laboratory. School teachers randomized under supervision the children to participate in this study and collected urine samples. All sampling plans (16.6), (14.5), (12.4), (10.3), (8.2), (6.1) et (4.0) allowed correct identification of hyper-endemic and hypo-endemic areas. Misclassifications occurred frequently for intermediate-endemic areas. The study confirms that the LQAS method by use of a (16.6) sampling plan constitute a valuable tool for large scale screening of hyper-endemic areas for therapeutic intervention as part of the control program. The study has also shown that school teachers may offer a potential source of manpower locally in such screening operations.

  16. ENHANCEMENT OF LEARNING ON SAMPLE SIZE CALCULATION WITH A SMARTPHONE APPLICATION: A CLUSTER-RANDOMIZED CONTROLLED TRIAL.

    PubMed

    Ngamjarus, Chetta; Chongsuvivatwong, Virasakdi; McNeil, Edward; Holling, Heinz

    2017-01-01

    Sample size determination usually is taught based on theory and is difficult to understand. Using a smartphone application to teach sample size calculation ought to be more attractive to students than using lectures only. This study compared levels of understanding of sample size calculations for research studies between participants attending a lecture only versus lecture combined with using a smartphone application to calculate sample sizes, to explore factors affecting level of post-test score after training sample size calculation, and to investigate participants’ attitude toward a sample size application. A cluster-randomized controlled trial involving a number of health institutes in Thailand was carried out from October 2014 to March 2015. A total of 673 professional participants were enrolled and randomly allocated to one of two groups, namely, 341 participants in 10 workshops to control group and 332 participants in 9 workshops to intervention group. Lectures on sample size calculation were given in the control group, while lectures using a smartphone application were supplied to the test group. Participants in the intervention group had better learning of sample size calculation (2.7 points out of maximnum 10 points, 95% CI: 24 - 2.9) than the participants in the control group (1.6 points, 95% CI: 1.4 - 1.8). Participants doing research projects had a higher post-test score than those who did not have a plan to conduct research projects (0.9 point, 95% CI: 0.5 - 1.4). The majority of the participants had a positive attitude towards the use of smartphone application for learning sample size calculation.

  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. A model-based 'varimax' sampling strategy for a heterogeneous population.

    PubMed

    Akram, Nuzhat A; Farooqi, Shakeel R

    2014-01-01

    Sampling strategies are planned to enhance the homogeneity of a sample, hence to minimize confounding errors. A sampling strategy was developed to minimize the variation within population groups. Karachi, the largest urban agglomeration in Pakistan, was used as a model population. Blood groups ABO and Rh factor were determined for 3000 unrelated individuals selected through simple random sampling. Among them five population groups, namely Balochi, Muhajir, Pathan, Punjabi and Sindhi, based on paternal ethnicity were identified. An index was designed to measure the proportion of admixture at parental and grandparental levels. Population models based on index score were proposed. For validation, 175 individuals selected through stratified random sampling were genotyped for the three STR loci CSF1PO, TPOX and TH01. ANOVA showed significant differences across the population groups for blood groups and STR loci distribution. Gene diversity was higher across the sub-population model than in the agglomerated population. At parental level gene diversities are significantly higher across No admixture models than Admixture models. At grandparental level the difference was not significant. A sub-population model with no admixture at parental level was justified for sampling the heterogeneous population of Karachi.

  19. DISABILITIES IN OKLAHOMA--ESTIMATES AND PROJECTIONS, REPORT OF THE OKLAHOMA SURVEY OF DISABILITIES.

    ERIC Educational Resources Information Center

    BOHLEBER, MICHAEL E.

    THE PURPOSE OF THE STUDY WAS TO PROVIDE REASONABLY ACCURATE ESTIMATES OF THE NUMBER AND TYPES OF DISABLED PERSONS AND THEIR NEEDS AS A BASIS FOR BOTH PRESENT AND FUTURE PLANNING. PERSONAL INTERVIEWS WERE CONDUCTED WITH ADULT RESPONDENTS IN 3,000 HOUSEHOLDS IN OKLAHOMA, A RANDOM SAMPLE STATIFIED ON THE RURAL-URBAN DIMENSION. DATA FROM 2,058…

  20. Oregon Works: Assessing the Worker Training and Work Organization Practices of Oregon Employers.

    ERIC Educational Resources Information Center

    Oregon State Economic Development Dept., Salem.

    In 1992, questionnaires regarding the training and work organization practices were mailed to a random sample of 4,000 Oregon employers, and focus groups were held with 100 Oregon managers/employers. The main findings from the completed questionnaires (43% response rate) were as follows: most Oregon employers do not plan for training or treat it…

  1. Using known map category marginal frequencies to improve estimates of thematic map accuracy

    NASA Technical Reports Server (NTRS)

    Card, D. H.

    1982-01-01

    By means of two simple sampling plans suggested in the accuracy-assessment literature, it is shown how one can use knowledge of map-category relative sizes to improve estimates of various probabilities. The fact that maximum likelihood estimates of cell probabilities for the simple random sampling and map category-stratified sampling were identical has permitted a unified treatment of the contingency-table analysis. A rigorous analysis of the effect of sampling independently within map categories is made possible by results for the stratified case. It is noted that such matters as optimal sample size selection for the achievement of a desired level of precision in various estimators are irrelevant, since the estimators derived are valid irrespective of how sample sizes are chosen.

  2. Effects of Ethnic Attributes on the Quality of Family Planning Services in Lima, Peru: A Randomized Crossover Trial

    PubMed Central

    Planas, Maria-Elena; García, Patricia J.; Bustelo, Monserrat; Carcamo, Cesar P.; Martinez, Sebastian; Nopo, Hugo; Rodriguez, Julio; Merino, Maria-Fernanda; Morrison, Andrew

    2015-01-01

    Most studies reporting ethnic disparities in the quality of healthcare come from developed countries and rely on observational methods. We conducted the first experimental study to evaluate whether health providers in Peru provide differential quality of care for family planning services, based on the indigenous or mestizo (mixed ethnoracial ancestry) profile of the patient. In a crossover randomized controlled trial conducted in 2012, a sample of 351 out of the 408 public health establishments in Metropolitan Lima, Peru were randomly assigned to receive unannounced simulated patients enacting indigenous and mestizo profiles (sequence-1) or mestizo and then indigenous profiles (sequence-2), with a five week wash-out period. Both ethnic profiles used the same scripted scenario for seeking contraceptive advice but had distinctive cultural attributes such as clothing, styling of hair, make-up, accessories, posture and patterns of movement and speech. Our primary outcome measure of quality of care is the proportion of technical tasks performed by providers, as established by Peruvian family planning clinical guidelines. Providers and data analysts were kept blinded to the allocation. We found a non-significant mean difference of -0·7% (p = 0·23) between ethnic profiles in the percentage of technical tasks performed by providers. However we report large deficiencies in the compliance with quality standards of care for both profiles. Differential provider behaviour based on the patient's ethnic profiles compared in the study did not contribute to deficiencies in family planning outcomes observed. The study highlights the need to explore other determinants for poor compliance with quality standards, including demand and supply side factors, and calls for interventions to improve the quality of care for family planning services in Metropolitan Lima. PMID:25671664

  3. Effects of ethnic attributes on the quality of family planning services in Lima, Peru: a randomized crossover trial.

    PubMed

    Planas, Maria-Elena; García, Patricia J; Bustelo, Monserrat; Carcamo, Cesar P; Martinez, Sebastian; Nopo, Hugo; Rodriguez, Julio; Merino, Maria-Fernanda; Morrison, Andrew

    2015-01-01

    Most studies reporting ethnic disparities in the quality of healthcare come from developed countries and rely on observational methods. We conducted the first experimental study to evaluate whether health providers in Peru provide differential quality of care for family planning services, based on the indigenous or mestizo (mixed ethnoracial ancestry) profile of the patient. In a crossover randomized controlled trial conducted in 2012, a sample of 351 out of the 408 public health establishments in Metropolitan Lima, Peru were randomly assigned to receive unannounced simulated patients enacting indigenous and mestizo profiles (sequence-1) or mestizo and then indigenous profiles (sequence-2), with a five week wash-out period. Both ethnic profiles used the same scripted scenario for seeking contraceptive advice but had distinctive cultural attributes such as clothing, styling of hair, make-up, accessories, posture and patterns of movement and speech. Our primary outcome measure of quality of care is the proportion of technical tasks performed by providers, as established by Peruvian family planning clinical guidelines. Providers and data analysts were kept blinded to the allocation. We found a non-significant mean difference of -0.7% (p = 0.23) between ethnic profiles in the percentage of technical tasks performed by providers. However we report large deficiencies in the compliance with quality standards of care for both profiles. Differential provider behaviour based on the patient's ethnic profiles compared in the study did not contribute to deficiencies in family planning outcomes observed. The study highlights the need to explore other determinants for poor compliance with quality standards, including demand and supply side factors, and calls for interventions to improve the quality of care for family planning services in Metropolitan Lima.

  4. Evaluation of a women group led health communication program in Haryana, India.

    PubMed

    Kaur, Manmeet; Jaswal, Nidhi; Saddi, Anil Kumar

    2017-12-01

    Sakshar Mahila Smooh (SMS) program was launched in rural areas of Haryana in India during 2008. A total of 6788 SMSs, each having 5-10 literate women, were equipped to enhance health communication. We carried out process evaluation of this program as an external agency. After a review of program documents, a random sample survey of Auxiliary Nurse Midwives (ANMs), SMS members, and village women was conducted. Out of four divisions of the state, one was randomly chosen, which had five districts. From 330 randomly chosen villages, 283 ANMs, 1164 SMS members, and 1123 village women were interviewed using a semi- structured interview schedule. Program inputs, processes, and outputs were compared in the five districts. Chi square was used for significance test. In the sampled division, out of 2009 villages, 1732 (86%) had functional SMS. In three years, SMS conducted 15036 group meetings, 2795 rallies, 2048 wall writings, and 803 competitions, and 44.5% of allocated budget was utilized. Most ANMs opined that SMSs are better health communicators. SMS members were aware about their roles and responsibilities. Majority of village women reported that SMS carry out useful health education activities. The characteristics of SMS members were similar but program performance was better in districts where health managers were proactive in program planning and monitoring. SMS Program has communicated health messages to majority of rural population, however, better planning & monitoring can improve program performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Incorporating uncertainty and motion in Intensity Modulated Radiation Therapy treatment planning

    NASA Astrophysics Data System (ADS)

    Martin, Benjamin Charles

    In radiation therapy, one seeks to destroy a tumor while minimizing the damage to surrounding healthy tissue. Intensity Modulated Radiation Therapy (IMRT) uses overlapping beams of x-rays that add up to a high dose within the target and a lower dose in the surrounding healthy tissue. IMRT relies on optimization techniques to create high quality treatments. Unfortunately, the possible conformality is limited by the need to ensure coverage even if there is organ movement or deformation. Currently, margins are added around the tumor to ensure coverage based on an assumed motion range. This approach does not ensure high quality treatments. In the standard IMRT optimization problem, an objective function measures the deviation of the dose from the clinical goals. The optimization then finds the beamlet intensities that minimize the objective function. When modeling uncertainty, the dose delivered from a given set of beamlet intensities is a random variable. Thus the objective function is also a random variable. In our stochastic formulation we minimize the expected value of this objective function. We developed a problem formulation that is both flexible and fast enough for use on real clinical cases. While working on accelerating the stochastic optimization, we developed a technique of voxel sampling. Voxel sampling is a randomized algorithms approach to a steepest descent problem based on estimating the gradient by only calculating the dose to a fraction of the voxels within the patient. When combined with an automatic sampling rate adaptation technique, voxel sampling produced an order of magnitude speed up in IMRT optimization. We also develop extensions of our results to Intensity Modulated Proton Therapy (IMPT). Due to the physics of proton beams the stochastic formulation yields visibly different and better plans than normal optimization. The results of our research have been incorporated into a software package OPT4D, which is an IMRT and IMPT optimization tool that we developed.

  6. Long-term care planning and preparation among persons with multiple sclerosis.

    PubMed

    Putnam, Michelle; Tang, Fengyan

    2008-01-01

    Individuals with multiple sclerosis (MS) primarily rely on informal supports such as family members and assistive technology to meet their daily needs. As they age, formal supports may become important to compliment these supports and sustain community-based living. No previous research exists exploring plans and preparations of persons with MS for future independent living and long-term care needs. We analyzed data from a random sample survey (N = 580) to assess knowledge and perceptions of future service needs using ANOVA, chi-square, correlations, and MANOVA procedures. Results indicate that overall, most respondents are not well informed and have not planned or prepared for future care needs. Persons reporting severe MS were more likely to plan and prepare. Key "entry points" for making preparations include receiving specific education and planning information, discussions with family and professional service providers, and increased age, education, and income. We recommend greater infusion of long-term care planning into these existing entry points and creation of new entry points including healthcare provides and insurers.

  7. Digital versus analogue preoperative planning of total hip arthroplasties: a randomized clinical trial of 210 total hip arthroplasties.

    PubMed

    The, Bertram; Verdonschot, Nico; van Horn, Jim R; van Ooijen, Peter M A; Diercks, Ron L

    2007-09-01

    The objective of this randomized clinical trial was to compare the clinical and technical results of digital preoperative planning for primary total hip arthroplasties with analogue planning. Two hundred and ten total hip arthroplasties were randomized. All plans were constructed on standardized radiographs by the surgeon who performed the arthroplasty the next day. The main outcome was accuracy of the preoperative plan. Secondary outcomes were operation time and a radiographic assessment of the arthroplasty. Digital preoperative plans were more accurate in planning the cup (P < .05) and scored higher on the postoperative radiologic assessment of cemented cup (P = .03) and stem (P < .01) components. None of the other comparisons reached statistical significance. We conclude that digital plans slightly outperform analogue plans.

  8. North American vegetation model for land-use planning in a changing climate: A solution to large classification problems

    Treesearch

    Gerald E. Rehfeldt; Nicholas L. Crookston; Cuauhtemoc Saenz-Romero; Elizabeth M. Campbell

    2012-01-01

    Data points intensively sampling 46 North American biomes were used to predict the geographic distribution of biomes from climate variables using the Random Forests classification tree. Techniques were incorporated to accommodate a large number of classes and to predict the future occurrence of climates beyond the contemporary climatic range of the biomes. Errors of...

  9. The Needs of Tribal Men and the Social Service Providers on or Near the Nez Perce Indian Nation.

    ERIC Educational Resources Information Center

    High Eagle, Gordon; And Others

    This report results from an action research project of the Nee Mee Poom Ha Hum (Men's Coalition), investigating the needs of tribal men in the Nez Perce Indian Nation, as part of planning to improve men's development. Research was directed toward interviewing a stratified random sample of tribal men and interviewing the directors and employees of…

  10. 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

  11. A method to estimate the effect of deformable image registration uncertainties on daily dose mapping

    PubMed Central

    Murphy, Martin J.; Salguero, Francisco J.; Siebers, Jeffrey V.; Staub, David; Vaman, Constantin

    2012-01-01

    Purpose: To develop a statistical sampling procedure for spatially-correlated uncertainties in deformable image registration and then use it to demonstrate their effect on daily dose mapping. Methods: Sequential daily CT studies are acquired to map anatomical variations prior to fractionated external beam radiotherapy. The CTs are deformably registered to the planning CT to obtain displacement vector fields (DVFs). The DVFs are used to accumulate the dose delivered each day onto the planning CT. Each DVF has spatially-correlated uncertainties associated with it. Principal components analysis (PCA) is applied to measured DVF error maps to produce decorrelated principal component modes of the errors. The modes are sampled independently and reconstructed to produce synthetic registration error maps. The synthetic error maps are convolved with dose mapped via deformable registration to model the resulting uncertainty in the dose mapping. The results are compared to the dose mapping uncertainty that would result from uncorrelated DVF errors that vary randomly from voxel to voxel. Results: The error sampling method is shown to produce synthetic DVF error maps that are statistically indistinguishable from the observed error maps. Spatially-correlated DVF uncertainties modeled by our procedure produce patterns of dose mapping error that are different from that due to randomly distributed uncertainties. Conclusions: Deformable image registration uncertainties have complex spatial distributions. The authors have developed and tested a method to decorrelate the spatial uncertainties and make statistical samples of highly correlated error maps. The sample error maps can be used to investigate the effect of DVF uncertainties on daily dose mapping via deformable image registration. An initial demonstration of this methodology shows that dose mapping uncertainties can be sensitive to spatial patterns in the DVF uncertainties. PMID:22320766

  12. Quantifying the benefit of wellbore leakage potential estimates for prioritizing long-term MVA well sampling at a CO2 storage site.

    PubMed

    Azzolina, Nicholas A; Small, Mitchell J; Nakles, David V; Glazewski, Kyle A; Peck, Wesley D; Gorecki, Charles D; Bromhal, Grant S; Dilmore, Robert M

    2015-01-20

    This work uses probabilistic methods to simulate a hypothetical geologic CO2 storage site in a depleted oil and gas field, where the large number of legacy wells would make it cost-prohibitive to sample all wells for all measurements as part of the postinjection site care. Deep well leakage potential scores were assigned to the wells using a random subsample of 100 wells from a detailed study of 826 legacy wells that penetrate the basal Cambrian formation on the U.S. side of the U.S./Canadian border. Analytical solutions and Monte Carlo simulations were used to quantify the statistical power of selecting a leaking well. Power curves were developed as a function of (1) the number of leaking wells within the Area of Review; (2) the sampling design (random or judgmental, choosing first the wells with the highest deep leakage potential scores); (3) the number of wells included in the monitoring sampling plan; and (4) the relationship between a well’s leakage potential score and its relative probability of leakage. Cases where the deep well leakage potential scores are fully or partially informative of the relative leakage probability are compared to a noninformative base case in which leakage is equiprobable across all wells in the Area of Review. The results show that accurate prior knowledge about the probability of well leakage adds measurable value to the ability to detect a leaking well during the monitoring program, and that the loss in detection ability due to imperfect knowledge of the leakage probability can be quantified. This work underscores the importance of a data-driven, risk-based monitoring program that incorporates uncertainty quantification into long-term monitoring sampling plans at geologic CO2 storage sites.

  13. Planning spatial sampling of the soil from an uncertain reconnaissance variogram

    NASA Astrophysics Data System (ADS)

    Lark, R. Murray; Hamilton, Elliott M.; Kaninga, Belinda; Maseka, Kakoma K.; Mutondo, Moola; Sakala, Godfrey M.; Watts, Michael J.

    2017-12-01

    An estimated variogram of a soil property can be used to support a rational choice of sampling intensity for geostatistical mapping. However, it is known that estimated variograms are subject to uncertainty. In this paper we address two practical questions. First, how can we make a robust decision on sampling intensity, given the uncertainty in the variogram? Second, what are the costs incurred in terms of oversampling because of uncertainty in the variogram model used to plan sampling? To achieve this we show how samples of the posterior distribution of variogram parameters, from a computational Bayesian analysis, can be used to characterize the effects of variogram parameter uncertainty on sampling decisions. We show how one can select a sample intensity so that a target value of the kriging variance is not exceeded with some specified probability. This will lead to oversampling, relative to the sampling intensity that would be specified if there were no uncertainty in the variogram parameters. One can estimate the magnitude of this oversampling by treating the tolerable grid spacing for the final sample as a random variable, given the target kriging variance and the posterior sample values. We illustrate these concepts with some data on total uranium content in a relatively sparse sample of soil from agricultural land near mine tailings in the Copperbelt Province of Zambia.

  14. Generalized Ensemble Sampling of Enzyme Reaction Free Energy Pathways

    PubMed Central

    Wu, Dongsheng; Fajer, Mikolai I.; Cao, Liaoran; Cheng, Xiaolin; Yang, Wei

    2016-01-01

    Free energy path sampling plays an essential role in computational understanding of chemical reactions, particularly those occurring in enzymatic environments. Among a variety of molecular dynamics simulation approaches, the generalized ensemble sampling strategy is uniquely attractive for the fact that it not only can enhance the sampling of rare chemical events but also can naturally ensure consistent exploration of environmental degrees of freedom. In this review, we plan to provide a tutorial-like tour on an emerging topic: generalized ensemble sampling of enzyme reaction free energy path. The discussion is largely focused on our own studies, particularly ones based on the metadynamics free energy sampling method and the on-the-path random walk path sampling method. We hope that this mini presentation will provide interested practitioners some meaningful guidance for future algorithm formulation and application study. PMID:27498634

  15. Animal research as a basis for clinical trials.

    PubMed

    Faggion, Clovis M

    2015-04-01

    Animal experiments are critical for the development of new human therapeutics because they provide mechanistic information, as well as important information on efficacy and safety. Some evidence suggests that authors of animal research in dentistry do not observe important methodological issues when planning animal experiments, for example sample-size calculation. Low-quality animal research directly interferes with development of the research process in which multiple levels of research are interconnected. For example, high-quality animal experiments generate sound information for the further planning and development of randomized controlled trials in humans. These randomized controlled trials are the main source for the development of systematic reviews and meta-analyses, which will generate the best evidence for the development of clinical guidelines. Therefore, adequate planning of animal research is a sine qua non condition for increasing efficacy and efficiency in research. Ethical concerns arise when animal research is not performed with high standards. This Focus article presents the latest information on the standards of animal research in dentistry, more precisely in the field of implant dentistry. Issues on precision and risk of bias are discussed, and strategies to reduce risk of bias in animal research are reported. © 2015 Eur J Oral Sci.

  16. Differences in Reporting of Analyses in Internal Company Documents Versus Published Trial Reports: Comparisons in Industry-Sponsored Trials in Off-Label Uses of Gabapentin

    PubMed Central

    Vedula, S. Swaroop; Li, Tianjing; Dickersin, Kay

    2013-01-01

    Background Details about the type of analysis (e.g., intent to treat [ITT]) and definitions (i.e., criteria for including participants in the analysis) are necessary for interpreting a clinical trial's findings. Our objective was to compare the description of types of analyses and criteria for including participants in the publication (i.e., what was reported) with descriptions in the corresponding internal company documents (i.e., what was planned and what was done). Trials were for off-label uses of gabapentin sponsored by Pfizer and Parke-Davis, and documents were obtained through litigation. Methods and Findings For each trial, we compared internal company documents (protocols, statistical analysis plans, and research reports, all unpublished), with publications. One author extracted data and another verified, with a third person verifying discordant items and a sample of the rest. Extracted data included the number of participants randomized and analyzed for efficacy, and types of analyses for efficacy and safety and their definitions (i.e., criteria for including participants in each type of analysis). We identified 21 trials, 11 of which were published randomized controlled trials, and that provided the documents needed for planned comparisons. For three trials, there was disagreement on the number of randomized participants between the research report and publication. Seven types of efficacy analyses were described in the protocols, statistical analysis plans, and publications, including ITT and six others. The protocol or publication described ITT using six different definitions, resulting in frequent disagreements between the two documents (i.e., different numbers of participants were included in the analyses). Conclusions Descriptions of analyses conducted did not agree between internal company documents and what was publicly reported. Internal company documents provide extensive documentation of methods planned and used, and trial findings, and should be publicly accessible. Reporting standards for randomized controlled trials should recommend transparent descriptions and definitions of analyses performed and which study participants are excluded. Please see later in the article for the Editors' Summary PMID:23382656

  17. Summarized Costs, Placement Of Quality Stars, And Other Online Displays Can Help Consumers Select High-Value Health Plans.

    PubMed

    Greene, Jessica; Hibbard, Judith H; Sacks, Rebecca M

    2016-04-01

    Starting in 2017, all state and federal health insurance exchanges will present quality data on health plans in addition to cost information. We analyzed variations in the current design of information on state exchanges to identify presentation approaches that encourage consumers to take quality as well as cost into account when selecting a health plan. Using an online sample of 1,025 adults, we randomly assigned participants to view the same comparative information on health plans, displayed in different ways. We found that consumers were much more likely to select a high-value plan when cost information was summarized instead of detailed, when quality stars were displayed adjacent to cost information, when consumers understood that quality stars signified the quality of medical care, and when high-value plans were highlighted with a check mark or blue ribbon. These approaches, which were equally effective for participants with higher and lower numeracy, can inform the development of future displays of plan information in the exchanges. Project HOPE—The People-to-People Health Foundation, Inc.

  18. Meeting Postpartum Women’s Family Planning Needs Through Integrated Family Planning and Immunization Services: Results of a Cluster-Randomized Controlled Trial in Rwanda

    PubMed Central

    Dulli, Lisa S; Eichleay, Marga; Rademacher, Kate; Sortijas, Steve; Nsengiyumva, Théophile

    2016-01-01

    ABSTRACT Objective The primary objective of this study was to test the effectiveness of integrating family planning service components into infant immunization services to increase modern contraceptive method use among postpartum women. Methods The study was a separate sample, parallel, cluster-randomized controlled trial. Fourteen randomly selected primary health facilities were equally allocated to intervention (integrated family planning and immunization services at the same time and location) and control groups (standard immunization services only). At baseline (May–June 2010), we interviewed postpartum women attending immunization services for their infant aged 6 to 12 months using a structured questionnaire. A separate sample of postpartum women was interviewed 16 months later after implementation of the experimental health service intervention. We used linear mixed regression models to test the study hypothesis that postpartum women attending immunization services for their infants aged 6–12 months in the intervention facilities will be more likely to use a modern contraceptive method than postpartum women attending immunization services for their infants aged 6–12 months in control group facilities. Results We interviewed and analyzed data for 825 women from the intervention group and 829 women from the control group. Results showed the intervention had a statistically significant, positive effect on modern contraceptive method use among intervention group participants compared with control group participants (regression coefficient, 0.15; 90% confidence interval [CI], 0.04 to 0.26). Although we conducted a 1-sided significance test, this effect was also significant at the 2-sided test with alpha = .05. Among those women who did not initiate a contraceptive method, awaiting the return of menses was the most common reason cited for non-use of a method. Women in both study groups overwhelmingly supported the concept of integrating family planning service components into infant immunization services (97.9% in each group), and service data collected during the intervention period did not indicate that the intervention had any negative effect on infant immunization service uptake. Conclusion Integrating family planning service components into infant immunization services can be an acceptable and effective strategy to increase contraceptive use among postpartum women. Additional research is needed to examine the extent to which this integration strategy can be replicated in other health care settings. Future research should also explore persistent misconceptions regarding the relationship between return of menses and return to fertility during the postpartum period. PMID:27016545

  19. Quantification of diabetes consultations by the main primary health care nurse groups in Auckland, New Zealand.

    PubMed

    Daly, Barbara; Arroll, Bruce; Sheridan, Nicolette; Kenealy, Timothy; Scragg, Robert

    2016-09-01

    Diabetes prevalence continues to increase, with most diabetes patients managed in primary care. This report quantifies the number of diabetes consultations undertaken by primary healthcare nurses in Auckland, New Zealand. Of 335 primary healthcare nurses randomly selected, 287 (86%) completed a telephone interview in 2006-2008. On a randomly sampled day (from the past seven) for each nurse, 42% of the nurses surveyed (n=120) consulted 308 diabetes patients. From the proportion of nurses sampled in the study, it is calculated that the number of diabetes patients consulted by primary healthcare nurses per week in Auckland between September 2006 and February 2008 was 4210, with 61% consulted by practice, 23% by specialist and 16% by district nurses. These findings show that practice nurses carry out the largest number of community diabetes consultations by nurses. Their major contribution needs to be incorporated into future planning of the community management of diabetes.

  20. Community Game Day: Using an End-of-Life Conversation Game to Encourage Advance Care Planning.

    PubMed

    Van Scoy, Lauren J; Reading, Jean M; Hopkins, Margaret; Smith, Brandi; Dillon, Judy; Green, Michael J; Levi, Benjamin H

    2017-11-01

    Advance care planning (ACP) is an important process that involves discussing and documenting one's values and preferences for medical care, particularly end-of-life treatments. This convergent, mixed-methods study assessed whether an end-of-life conversation card game is an acceptable and effective means for performing ACP for patients with chronic illness and/or their caregivers when deployed in a community setting. Twenty-two games (n = 93 participants) were held in community settings surrounding Hershey, PA in 2016. Participants were recruited using random sampling from patient databases and also convenience sampling (i.e., flyers). Quantitative questionnaires and qualitative focus group interviews were administered to assess the game experience and subsequent performance of ACP behaviors. Both quantitative and qualitative data found that Community Game Day was a well-received, positive experience for participants and 75% of participants performed ACP within three months post-intervention. These findings suggest that using a conversation game during community outreach is a useful approach for engaging patients and caregivers in ACP. The convergence of quantitative and qualitative data strongly supports the continued investigation of the game in randomized controlled trials. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  1. Statistical analysis plan for the Alveolar Recruitment for Acute Respiratory Distress Syndrome Trial (ART). A randomized controlled trial

    PubMed Central

    Damiani, Lucas Petri; Berwanger, Otavio; Paisani, Denise; Laranjeira, Ligia Nasi; Suzumura, Erica Aranha; Amato, Marcelo Britto Passos; Carvalho, Carlos Roberto Ribeiro; Cavalcanti, Alexandre Biasi

    2017-01-01

    Background The Alveolar Recruitment for Acute Respiratory Distress Syndrome Trial (ART) is an international multicenter randomized pragmatic controlled trial with allocation concealment involving 120 intensive care units in Brazil, Argentina, Colombia, Italy, Poland, Portugal, Malaysia, Spain, and Uruguay. The primary objective of ART is to determine whether maximum stepwise alveolar recruitment associated with PEEP titration, adjusted according to the static compliance of the respiratory system (ART strategy), is able to increase 28-day survival in patients with acute respiratory distress syndrome compared to conventional treatment (ARDSNet strategy). Objective To describe the data management process and statistical analysis plan. Methods The statistical analysis plan was designed by the trial executive committee and reviewed and approved by the trial steering committee. We provide an overview of the trial design with a special focus on describing the primary (28-day survival) and secondary outcomes. We describe our data management process, data monitoring committee, interim analyses, and sample size calculation. We describe our planned statistical analyses for primary and secondary outcomes as well as pre-specified subgroup analyses. We also provide details for presenting results, including mock tables for baseline characteristics, adherence to the protocol and effect on clinical outcomes. Conclusion According to best trial practice, we report our statistical analysis plan and data management plan prior to locking the database and beginning analyses. We anticipate that this document will prevent analysis bias and enhance the utility of the reported results. Trial registration ClinicalTrials.gov number, NCT01374022. PMID:28977255

  2. The role of descriptive norm within the theory of planned behavior in predicting Korean Americans' exercise behavior.

    PubMed

    Lee, Hyo

    2011-08-01

    There are few studies investigating psychosocial mechanisms in Korean Americans' exercise behavior. The present study tested the usefulness of the theory of planned behavior in predicting Korean American's exercise behavior and whether the descriptive norm (i.e., perceptions of what others do) improved the predictive validity of the theory of planned behavior. Using a retrospective design and self-report measures, web-survey responses from 198 Korean-American adults were analyzed using hierarchical regression analyses. The theory of planned behavior constructs accounted for 31% of exercise behavior and 43% of exercise intention. Intention and perceived behavioral control were significant predictors of exercise behavior. Although the descriptive norm did not augment the theory of planned behavior, all original constructs--attitude, injunctive norm (a narrow definition of subjective norm), and perceived behavioral control--statistically significantly predicted leisure-time physical activity intention. Future studies should consider random sampling, prospective design, and objective measures of physical activity.

  3. Group versus individual family planning counseling in Ghana: a randomized, noninferiority trial.

    PubMed

    Schwandt, Hilary M; Creanga, Andreea A; Danso, Kwabena A; Adanu, Richard M K; Agbenyega, Tsiri; Hindin, Michelle J

    2013-08-01

    Group, rather than individual, family planning counseling has the potential to increase family planning knowledge and use through more efficient use of limited human resources. A randomized, noninferiority study design was utilized to identify whether group family planning counseling is as effective as individual family planning counseling in Ghana. Female gynecology patients were enrolled from two teaching hospitals in Ghana in June and July 2008. Patients were randomized to receive either group or individual family planning counseling. The primary outcome in this study was change in modern contraceptive method knowledge. Changes in family planning use intention before and after the intervention and intended method type were also explored. Comparisons between the two study arms suggest that randomization was successful. The difference in change in modern contraceptive methods known from baseline to follow-up between the two study arms (group-individual), adjusted for study site, was -0.21, (95% confidence interval: -0.53 to 0.12) suggesting no difference between the two arms. Group family planning counseling was as effective as individual family planning counseling in increasing modern contraceptive knowledge among female gynecology patients in Ghana. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Corporate social marketing: message design to recruit program participants.

    PubMed

    Black, David R; Blue, Carolyn L; Coster, Daniel C; Chrysler, Lisa M

    2002-01-01

    To identify variables for a corporate social marketing (SM) health message based on the 4 Ps of SM in order to recruit future participants to an existing national, commercial, self-administered weight-loss program. A systematically evaluated, author-developed, 310-response survey was administered to a random sample of 270 respondents. A previously established research plan was used to empirically identify the audience segments and the "marketing mix" appropriate for the total sample and each segment. Tangible product, pertaining to the unique program features, should be emphasized rather than positive core product and outcome expectation related to use of the program.

  5. Operational feasibility of lot quality assurance sampling (LQAS) as a tool in routine process monitoring of filariasis control programmes.

    PubMed

    Vanamail, P; Subramanian, S; Srividya, A; Ravi, R; Krishnamoorthy, K; Das, P K

    2006-08-01

    Lot quality assurance sampling (LQAS) with two-stage sampling plan was applied for rapid monitoring of coverage after every round of mass drug administration (MDA). A Primary Health Centre (PHC) consisting of 29 villages in Thiruvannamalai district, Tamil Nadu was selected as the study area. Two threshold levels of coverage were used: threshold A (maximum: 60%; minimum: 40%) and threshold B (maximum: 80%; minimum: 60%). Based on these thresholds, one sampling plan each for A and B was derived with the necessary sample size and the number of allowable defectives (i.e. defectives mean those who have not received the drug). Using data generated through simple random sampling (SRSI) of 1,750 individuals in the study area, LQAS was validated with the above two sampling plans for its diagnostic and field applicability. Simultaneously, a household survey (SRSH) was conducted for validation and cost-effectiveness analysis. Based on SRSH survey, the estimated coverage was 93.5% (CI: 91.7-95.3%). LQAS with threshold A revealed that by sampling a maximum of 14 individuals and by allowing four defectives, the coverage was >or=60% in >90% of villages at the first stage. Similarly, with threshold B by sampling a maximum of nine individuals and by allowing four defectives, the coverage was >or=80% in >90% of villages at the first stage. These analyses suggest that the sampling plan (14,4,52,25) of threshold A may be adopted in MDA to assess if a minimum coverage of 60% has been achieved. However, to achieve the goal of elimination, the sampling plan (9, 4, 42, 29) of threshold B can identify villages in which the coverage is <80% so that remedial measures can be taken. Cost-effectiveness analysis showed that both options of LQAS are more cost-effective than SRSH to detect a village with a given level of coverage. The cost per village was US dollars 76.18 under SRSH. The cost of LQAS was US dollars 65.81 and 55.63 per village for thresholds A and B respectively. The total financial cost of classifying a village correctly with the given threshold level of LQAS could be reduced by 14% and 26% of the cost of conventional SRSH method.

  6. Maximum type I error rate inflation from sample size reassessment when investigators are blind to treatment labels.

    PubMed

    Żebrowska, Magdalena; Posch, Martin; Magirr, Dominic

    2016-05-30

    Consider a parallel group trial for the comparison of an experimental treatment to a control, where the second-stage sample size may depend on the blinded primary endpoint data as well as on additional blinded data from a secondary endpoint. For the setting of normally distributed endpoints, we demonstrate that this may lead to an inflation of the type I error rate if the null hypothesis holds for the primary but not the secondary endpoint. We derive upper bounds for the inflation of the type I error rate, both for trials that employ random allocation and for those that use block randomization. We illustrate the worst-case sample size reassessment rule in a case study. For both randomization strategies, the maximum type I error rate increases with the effect size in the secondary endpoint and the correlation between endpoints. The maximum inflation increases with smaller block sizes if information on the block size is used in the reassessment rule. Based on our findings, we do not question the well-established use of blinded sample size reassessment methods with nuisance parameter estimates computed from the blinded interim data of the primary endpoint. However, we demonstrate that the type I error rate control of these methods relies on the application of specific, binding, pre-planned and fully algorithmic sample size reassessment rules and does not extend to general or unplanned sample size adjustments based on blinded data. © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

  7. Effect of patient setup errors on simultaneously integrated boost head and neck IMRT treatment plans

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

    Siebers, Jeffrey V.; Keall, Paul J.; Wu Qiuwen

    2005-10-01

    Purpose: The purpose of this study is to determine dose delivery errors that could result from random and systematic setup errors for head-and-neck patients treated using the simultaneous integrated boost (SIB)-intensity-modulated radiation therapy (IMRT) technique. Methods and Materials: Twenty-four patients who participated in an intramural Phase I/II parotid-sparing IMRT dose-escalation protocol using the SIB treatment technique had their dose distributions reevaluated to assess the impact of random and systematic setup errors. The dosimetric effect of random setup error was simulated by convolving the two-dimensional fluence distribution of each beam with the random setup error probability density distribution. Random setup errorsmore » of {sigma} = 1, 3, and 5 mm were simulated. Systematic setup errors were simulated by randomly shifting the patient isocenter along each of the three Cartesian axes, with each shift selected from a normal distribution. Systematic setup error distributions with {sigma} = 1.5 and 3.0 mm along each axis were simulated. Combined systematic and random setup errors were simulated for {sigma} = {sigma} = 1.5 and 3.0 mm along each axis. For each dose calculation, the gross tumor volume (GTV) received by 98% of the volume (D{sub 98}), clinical target volume (CTV) D{sub 90}, nodes D{sub 90}, cord D{sub 2}, and parotid D{sub 50} and parotid mean dose were evaluated with respect to the plan used for treatment for the structure dose and for an effective planning target volume (PTV) with a 3-mm margin. Results: Simultaneous integrated boost-IMRT head-and-neck treatment plans were found to be less sensitive to random setup errors than to systematic setup errors. For random-only errors, errors exceeded 3% only when the random setup error {sigma} exceeded 3 mm. Simulated systematic setup errors with {sigma} = 1.5 mm resulted in approximately 10% of plan having more than a 3% dose error, whereas a {sigma} = 3.0 mm resulted in half of the plans having more than a 3% dose error and 28% with a 5% dose error. Combined random and systematic dose errors with {sigma} = {sigma} = 3.0 mm resulted in more than 50% of plans having at least a 3% dose error and 38% of the plans having at least a 5% dose error. Evaluation with respect to a 3-mm expanded PTV reduced the observed dose deviations greater than 5% for the {sigma} = {sigma} = 3.0 mm simulations to 5.4% of the plans simulated. Conclusions: Head-and-neck SIB-IMRT dosimetric accuracy would benefit from methods to reduce patient systematic setup errors. When GTV, CTV, or nodal volumes are used for dose evaluation, plans simulated including the effects of random and systematic errors deviate substantially from the nominal plan. The use of PTVs for dose evaluation in the nominal plan improves agreement with evaluated GTV, CTV, and nodal dose values under simulated setup errors. PTV concepts should be used for SIB-IMRT head-and-neck squamous cell carcinoma patients, although the size of the margins may be less than those used with three-dimensional conformal radiation therapy.« less

  8. Are women aware of religious restrictions on reproductive health at Catholic hospitals? A survey of women's expectations and preferences for family planning care.

    PubMed

    Guiahi, Maryam; Sheeder, Jeanelle; Teal, Stephanie

    2014-10-01

    To understand if women anticipate a difference in reproductive healthcare when attending a Catholic institution. A convenience sample of reproductive-aged women in the Denver metro area completed an online survey. Women were randomized to hypothetical women's health clinics at either a secular or Catholic hospital and asked about expectations for family planning care. Questions covered contraception and management of abnormal or unintended pregnancy. We subsequently assessed provider/site preferences for care. We analyzed 236 surveys. The majority of participants expected their gynecologist to provide all family planning services presented. The only difference based on institution was that participants randomized to the Catholic hospital were more likely to expect natural family planning advice. At least half of respondents reported they would seek care from their gynecologist for the services surveyed with the exceptions of emergency contraception and elective abortion. Overall, this cohort of women did not anticipate differences in reproductive healthcare based on institution. If women who enroll at Catholic hospitals do not receive information related to potential healthcare restrictions, their ability to act as informed healthcare consumers may be constrained. Women did not anticipate differences in reproductive healthcare based on institution type (Catholic vs. secular) and, thus, their ability to act as informed healthcare consumers may be constrained. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. A stochastic convolution/superposition method with isocenter sampling to evaluate intrafraction motion effects in IMRT.

    PubMed

    Naqvi, Shahid A; D'Souza, Warren D

    2005-04-01

    Current methods to calculate dose distributions with organ motion can be broadly classified as "dose convolution" and "fluence convolution" methods. In the former, a static dose distribution is convolved with the probability distribution function (PDF) that characterizes the motion. However, artifacts are produced near the surface and around inhomogeneities because the method assumes shift invariance. Fluence convolution avoids these artifacts by convolving the PDF with the incident fluence instead of the patient dose. In this paper we present an alternative method that improves the accuracy, generality as well as the speed of dose calculation with organ motion. The algorithm starts by sampling an isocenter point from a parametrically defined space curve corresponding to the patient-specific motion trajectory. Then a photon is sampled in the linac head and propagated through the three-dimensional (3-D) collimator structure corresponding to a particular MLC segment chosen randomly from the planned IMRT leaf sequence. The photon is then made to interact at a point in the CT-based simulation phantom. Randomly sampled monoenergetic kernel rays issued from this point are then made to deposit energy in the voxels. Our method explicitly accounts for MLC-specific effects (spectral hardening, tongue-and-groove, head scatter) as well as changes in SSD with isocentric displacement, assuming that the body moves rigidly with the isocenter. Since the positions are randomly sampled from a continuum, there is no motion discretization, and the computation takes no more time than a static calculation. To validate our method, we obtained ten separate film measurements of an IMRT plan delivered on a phantom moving sinusoidally, with each fraction starting with a random phase. For 2 cm motion amplitude, we found that a ten-fraction average of the film measurements gave an agreement with the calculated infinite fraction average to within 2 mm in the isodose curves. The results also corroborate the existing notion that the interfraction dose variability due to the interplay between the MLC motion and breathing motion averages out over typical multifraction treatments. Simulation with motion waveforms more representative of real breathing indicate that the motion can produce penumbral spreading asymmetric about the static dose distributions. Such calculations can help a clinician decide to use, for example, a larger margin in the superior direction than in the inferior direction. In the paper we demonstrate that a 15 min run on a single CPU can readily illustrate the effect of a patient-specific breathing waveform, and can guide the physician in making informed decisions about margin expansion and dose escalation.

  10. Developing and testing new smoking measures for the Health Plan Employer Data and Information Set.

    PubMed

    Pbert, Lori; Vuckovic, Nancy; Ockene, Judith K; Hollis, Jack F; Riedlinger, Karen

    2003-04-01

    To develop and test items for the Health Plan Employee Data and Information Set (HEDIS) that assess delivery of the full range of provider-delivered tobacco interventions. The authors identified potential items via literature review; items were reviewed by national experts. Face validity of candidate items was tested in focus groups. The final survey was sent to a random sample of 1711 adult primary care patients; the re-test survey was sent to self-identified smokers. The process identified reliable items to capture provider assessment of motivation and provision of assistance and follow-up. One can reliably assess patient self-report of provider delivery of the full range of brief tobacco interventions. Such assessment and feedback to health plans and providers may increase use of evidence-based brief interventions.

  11. Taking a statistical approach

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

    Wild, M.; Rouhani, S.

    1995-02-01

    A typical site investigation entails extensive sampling and monitoring. In the past, sampling plans have been designed on purely ad hoc bases, leading to significant expenditures and, in some cases, collection of redundant information. In many instances, sampling costs exceed the true worth of the collected data. The US Environmental Protection Agency (EPA) therefore has advocated the use of geostatistics to provide a logical framework for sampling and analysis of environmental data. Geostatistical methodology uses statistical techniques for the spatial analysis of a variety of earth-related data. The use of geostatistics was developed by the mining industry to estimate oremore » concentrations. The same procedure is effective in quantifying environmental contaminants in soils for risk assessments. Unlike classical statistical techniques, geostatistics offers procedures to incorporate the underlying spatial structure of the investigated field. Sample points spaced close together tend to be more similar than samples spaced further apart. This can guide sampling strategies and determine complex contaminant distributions. Geostatistic techniques can be used to evaluate site conditions on the basis of regular, irregular, random and even spatially biased samples. In most environmental investigations, it is desirable to concentrate sampling in areas of known or suspected contamination. The rigorous mathematical procedures of geostatistics allow for accurate estimates at unsampled locations, potentially reducing sampling requirements. The use of geostatistics serves as a decision-aiding and planning tool and can significantly reduce short-term site assessment costs, long-term sampling and monitoring needs, as well as lead to more accurate and realistic remedial design criteria.« less

  12. Sample size calculation in cost-effectiveness cluster randomized trials: optimal and maximin approaches.

    PubMed

    Manju, Md Abu; Candel, Math J J M; Berger, Martijn P F

    2014-07-10

    In this paper, the optimal sample sizes at the cluster and person levels for each of two treatment arms are obtained for cluster randomized trials where the cost-effectiveness of treatments on a continuous scale is studied. The optimal sample sizes maximize the efficiency or power for a given budget or minimize the budget for a given efficiency or power. Optimal sample sizes require information on the intra-cluster correlations (ICCs) for effects and costs, the correlations between costs and effects at individual and cluster levels, the ratio of the variance of effects translated into costs to the variance of the costs (the variance ratio), sampling and measuring costs, and the budget. When planning, a study information on the model parameters usually is not available. To overcome this local optimality problem, the current paper also presents maximin sample sizes. The maximin sample sizes turn out to be rather robust against misspecifying the correlation between costs and effects at the cluster and individual levels but may lose much efficiency when misspecifying the variance ratio. The robustness of the maximin sample sizes against misspecifying the ICCs depends on the variance ratio. The maximin sample sizes are robust under misspecification of the ICC for costs for realistic values of the variance ratio greater than one but not robust under misspecification of the ICC for effects. Finally, we show how to calculate optimal or maximin sample sizes that yield sufficient power for a test on the cost-effectiveness of an intervention.

  13. List randomization for soliciting experience of intimate partner violence: Application to the evaluation of Zambia's unconditional child grant program.

    PubMed

    Peterman, Amber; Palermo, Tia M; Handa, Sudhanshu; Seidenfeld, David

    2018-03-01

    Social scientists have increasingly invested in understanding how to improve data quality and measurement of sensitive topics in household surveys. We utilize the technique of list randomization to collect measures of physical intimate partner violence in an experimental impact evaluation of the Government of Zambia's Child Grant Program. The Child Grant Program is an unconditional cash transfer, which targeted female caregivers of children under the age of 5 in rural areas to receive the equivalent of US $24 as a bimonthly stipend. The implementation results show that the list randomization methodology functioned as planned, with approximately 15% of the sample identifying 12-month prevalence of physical intimate partner violence. According to this measure, after 4 years, the program had no measurable effect on partner violence. List randomization is a promising approach to incorporate sensitive measures into multitopic evaluations; however, more research is needed to improve upon methodology for application to measurement of violence. Copyright © 2017 John Wiley & Sons, Ltd.

  14. An Experimental Evaluation of Competing Age-Predictions of Future Time Perspective between Workplace and Retirement Domains.

    PubMed

    Kerry, Matthew J; Embretson, Susan E

    2017-01-01

    Future time perspective (FTP) is defined as "perceptions of the future as being limited or open-ended" (Lang and Carstensen, 2002; p. 125). The construct figures prominently in both workplace and retirement domains, but the age-predictions are competing: Workplace research predicts decreasing FTP age-change, in contrast, retirement scholars predict increasing FTP age-change. For the first time, these competing predictions are pitted in an experimental manipulation of subjective life expectancy (SLE). A sample of N = 207 older adults (age 45-60) working full-time (>30-h/week) were randomly assigned to SLE questions framed as either 'Live-to' or 'Die-by' to evaluate competing predictions for FTP. Results indicate general support for decreasing age-change in FTP, indicated by independent-sample t -tests showing lower FTP in the 'Die-by' framing condition. Further general-linear model analyses were conducted to test for interaction effects of retirement planning with experimental framings on FTP and intended retirement; While retirement planning buffered FTP's decrease, simple-effects also revealed that retirement planning increased intentions for sooner retirement, but lack of planning increased intentions for later retirement. Discussion centers on practical implications of our findings and consequences validity evidence in future empirical research of FTP in both workplace and retirement domains.

  15. Experimental Evaluation of Prepared Lesson Plans on Instruction in Vocational Agriculture.

    ERIC Educational Resources Information Center

    Ahrens, Donald Louis

    To determine the value of prepared lesson plans on instruction in vocational agriculture, 12 randomly selected Iowa high schools with approved vocational agriculture programs were randomly divided into two groups of six including a control group and a treatment group. Prepared lesson plans provided the only variance in instruction. Two meetings…

  16. Effect of attitudes and perceptions of independent community pharmacy owners/managers on the comprehensiveness of strategic planning.

    PubMed

    Harrison, Donald L

    2006-01-01

    To assess the attitudes and perceptions of independent community pharmacy owners/managers about the comprehensiveness of strategic planning conducted for their pharmacies. Cross-sectional study. United States. Nationwide random sample of 1,250 owners/managers of independent community pharmacies. Mailed survey. Comprehensiveness of strategic planning conducted; components used in the strategic planning process. Attitudes and perceptions of owners/managers of independent community pharmacies toward strategic planning. A total of 527 (42.1%) usable questionnaires were returned. Of the 141 (26.8%) respondents who indicated that they conduct strategic planning, most components of the process were used. However, only 78 (55.3%) of those respondents conducted a review of pharmacy systems, and only 60 (42.6%) periodically evaluated implemented strategies. Approximately 88% of the variance in comprehensiveness was accounted for by 12 variables identified as significantly associated with the comprehensiveness of strategic planning conducted by owners/managers of independent community pharmacies. These included factors such as favorable cost-benefit relationship, impact of the Medicare Modernization Act of 2003, and remaining competitive in the pharmacy marketplace. While a minority of the survey population, respondents who reported conducting strategic planning used a reasonably comprehensive process. Further, several variables were identified as significant factors associated with comprehensiveness of strategic planning conducted.

  17. Strategic planning by independent community pharmacies.

    PubMed

    Harrison, Donald L

    2005-01-01

    (1) To assess the degree and level of use of the strategic planning process (none, partly, fully) by independent community pharmacy owners/managers and (2) to evaluate the relationships between independent community pharmacy owners/managers' level of strategic planning and indicators of pharmacy performance; including new and refill prescriptions filled, gross margin, rated patient care performance, rated dispensing performance, rated non-pharmacy performance, and rated financial performance. Cross-sectional study. United States. Nationwide random sample of 1,250 owners/managers of independent community pharmacies. Mailed survey. Quality of strategic planning conducted; pharmacy performance measures. Only 141 of 527 (26.8%) usable responses indicated use of some (77 pharmacies, 54.6%) or all (64 pharmacies, 45.4%) of the seven steps typical of strategic planning. Significant associations were observed between the level of strategic planning use and all pharmacy performance variables assessed, including indicators such as greater numbers of new and refill prescriptions dispensed, gross margins, patient care performance, dispensing performance, non-pharmacy performance, and financial performance. Greater ratings of pharmacy performance were significantly associated with the level of strategic planning use. Respondents who fully used strategic planning had significantly higher indicators than partial users; respondents who partly used the process had significantly higher ratings than respondents who did not conduct strategic planning.

  18. Effect of Educational Intervention on the Fruit and Vegetables Consumption among the Students: Applying Theory of Planned Behavior.

    PubMed

    Taghdisi, Mohammad Hossein; Babazadeh, Towhid; Moradi, Fatemeh; Shariat, Fariba

    2016-01-01

    The importance of consuming fruits and vegetables (F&V) in prevention of chronic diseases is known. Childhood play an important role in formation of healthy eating habits. The purpose of this study was to examine the effect of education, with application of the theory of planned behavior, on improvement of F&V consumption. In this quasi-experimental study, 184 fourth, fifth, and sixth-grade students participated were enrolled from Jan 2013 to Jun 2014. The samples were selected from 6 schools in Chalderan County, West Azerbaijan, Iran through cluster random sampling method. Two out of 6 schools were randomly selected and each was employed in either experimental or control group. The data collection instruments included a researcher-made questionnaire and a 24-h F&V recall. Data were collected after verification of the reliability and validity of the questionnaire. Before the intervention, no significant difference was observed between the intervention and control group regarding attitude, subjective norms, perceived behavioral control, behavioral intention and fruits and vegetables consumption (P>0.05). However, after the educational intervention, the mean scores of attitude, subjective norms, perceived behavioral control, behavioral intention variables and fruits and vegetables were significantly higher in the intervention group when compared to the control group(P<0.05). Increased behavioral intention, attitude, subjective norms, and perceived behavioral control can promote F&V consumption among the students.

  19. Sample size calculations for the design of cluster randomized trials: A summary of methodology.

    PubMed

    Gao, Fei; Earnest, Arul; Matchar, David B; Campbell, Michael J; Machin, David

    2015-05-01

    Cluster randomized trial designs are growing in popularity in, for example, cardiovascular medicine research and other clinical areas and parallel statistical developments concerned with the design and analysis of these trials have been stimulated. Nevertheless, reviews suggest that design issues associated with cluster randomized trials are often poorly appreciated and there remain inadequacies in, for example, describing how the trial size is determined and the associated results are presented. In this paper, our aim is to provide pragmatic guidance for researchers on the methods of calculating sample sizes. We focus attention on designs with the primary purpose of comparing two interventions with respect to continuous, binary, ordered categorical, incidence rate and time-to-event outcome variables. Issues of aggregate and non-aggregate cluster trials, adjustment for variation in cluster size and the effect size are detailed. The problem of establishing the anticipated magnitude of between- and within-cluster variation to enable planning values of the intra-cluster correlation coefficient and the coefficient of variation are also described. Illustrative examples of calculations of trial sizes for each endpoint type are included. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Sample size estimation for alternating logistic regressions analysis of multilevel randomized community trials of under-age drinking.

    PubMed

    Reboussin, Beth A; Preisser, John S; Song, Eun-Young; Wolfson, Mark

    2012-07-01

    Under-age drinking is an enormous public health issue in the USA. Evidence that community level structures may impact on under-age drinking has led to a proliferation of efforts to change the environment surrounding the use of alcohol. Although the focus of these efforts is to reduce drinking by individual youths, environmental interventions are typically implemented at the community level with entire communities randomized to the same intervention condition. A distinct feature of these trials is the tendency of the behaviours of individuals residing in the same community to be more alike than that of others residing in different communities, which is herein called 'clustering'. Statistical analyses and sample size calculations must account for this clustering to avoid type I errors and to ensure an appropriately powered trial. Clustering itself may also be of scientific interest. We consider the alternating logistic regressions procedure within the population-averaged modelling framework to estimate the effect of a law enforcement intervention on the prevalence of under-age drinking behaviours while modelling the clustering at multiple levels, e.g. within communities and within neighbourhoods nested within communities, by using pairwise odds ratios. We then derive sample size formulae for estimating intervention effects when planning a post-test-only or repeated cross-sectional community-randomized trial using the alternating logistic regressions procedure.

  1. The Situation Analysis Study of the family planning program in Kenya.

    PubMed

    Miller, R A; Ndhlovu, L; Gachara, M M; Fisher, A A

    1991-01-01

    A new, relatively "quick and clean" operations research approach called a "situation analysis" was developed for examining the strengths and weaknesses of the family planning program of Kenya. Field research teams visited a stratified random sample of 99 of the Ministry of Health's approximately 775 service delivery points. Observation techniques and interviewing were used to collect information on program components and on the quality of care provided to new family planning clients during the observation day. As late as 1986, the Kenya program was rated "weak" and "poor" in the international literature. The Kenya Situation Analysis Study found a functioning, integrated maternal and child health/family planning program serving large numbers of clients, with an emphasis on oral contraceptives and Depo-Provera (and an underemphasis on permanent methods). Although a number of program problems were revealed by the study, overall, in terms of performance, a rating of "moderate" is suggested as more appropriate for Kenya's national family planning program today. In terms of the quality of care, a "moderate to moderate-high" rating is suggested.

  2. A general method for the definition of margin recipes depending on the treatment technique applied in helical tomotherapy prostate plans.

    PubMed

    Sevillano, David; Mínguez, Cristina; Sánchez, Alicia; Sánchez-Reyes, Alberto

    2016-01-01

    To obtain specific margin recipes that take into account the dosimetric characteristics of the treatment plans used in a single institution. We obtained dose-population histograms (DPHs) of 20 helical tomotherapy treatment plans for prostate cancer by simulating the effects of different systematic errors (Σ) and random errors (σ) on these plans. We obtained dosimetric margins and margin reductions due to random errors (random margins) by fitting the theoretical results of coverages for Gaussian distributions with coverages of the planned D99% obtained from the DPHs. The dosimetric margins obtained for helical tomotherapy prostate treatments were 3.3 mm, 3 mm, and 1 mm in the lateral (Lat), anterior-posterior (AP), and superior-inferior (SI) directions. Random margins showed parabolic dependencies, yielding expressions of 0.16σ(2), 0.13σ(2), and 0.15σ(2) for the Lat, AP, and SI directions, respectively. When focusing on values up to σ = 5 mm, random margins could be fitted considering Gaussian penumbras with standard deviations (σp) equal to 4.5 mm Lat, 6 mm AP, and 5.5 mm SI. Despite complex dose distributions in helical tomotherapy treatment plans, we were able to simplify the behaviour of our plans against treatment errors to single values of dosimetric and random margins for each direction. These margins allowed us to develop specific margin recipes for the respective treatment technique. The method is general and could be used for any treatment technique provided that DPHs can be obtained. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  3. Establishing the need for nutrition education: I. Methodology.

    PubMed

    Vaden, A G; Newell, G K; Dayton, A D; Foley, C S

    1983-10-01

    Developmental and data collection phases for a comprehensive needs assessment project designed to provide baseline data for planning a statewide nutrition education and training project are summarized. To meet project objectives, 97 Kansas elementary schools were selected randomly as sampling units. A mail questionnaire was used to assess nutrition knowledge and attitudes and dietary and nutrition education practices of elementary teachers and food service personnel. Data from fifth grade students were collected on-site at each school. A written test was used to measure students' nutrition knowledge, attitudes, and practices. Students' nutritional status was partially assessed by measuring their height, weight, skinfold thickness, and upper arm circumference. As an additional assessment, 24-hour dietary recall interviews were conducted with a random sample of the students. In this article, each aspect of the data collection methodology is described in detail. As emphasized by authorities in the field, more complete information is needed in many nutrition survey reports to assist in useful interpretations and for comparisons among studies.

  4. A comprehensive algorithm for determining whether a run-in strategy will be a cost-effective design modification in a randomized clinical trial.

    PubMed

    Schechtman, K B; Gordon, M E

    1993-01-30

    In randomized clinical trials, poor compliance and treatment intolerance lead to reduced between-group differences, increased sample size requirements, and increased cost. A run-in strategy is intended to reduce these problems. In this paper, we develop a comprehensive set of measures specifically sensitive to the effect of a run-in on cost and sample size requirements, both before and after randomization. Using these measures, we describe a step-by-step algorithm through which one can estimate the cost-effectiveness of a potential run-in. Because the cost-effectiveness of a run-in is partly mediated by its effect on sample size, we begin by discussing the likely impact of a planned run-in on the required number of randomized, eligible, and screened subjects. Run-in strategies are most likely to be cost-effective when: (1) per patient costs during the post-randomization as compared to the screening period are high; (2) poor compliance is associated with a substantial reduction in response to treatment; (3) the number of screened patients needed to identify a single eligible patient is small; (4) the run-in is inexpensive; (5) for most patients, the run-in compliance status is maintained following randomization and, most importantly, (6) many subjects excluded by the run-in are treatment intolerant or non-compliant to the extent that we expect little or no treatment response. Our analysis suggests that conditions for the cost-effectiveness of run-in strategies are stringent. In particular, if the only purpose of a run-in is to exclude ordinary partial compliers, the run-in will frequently add to the cost of the trial. Often, the cost-effectiveness of a run-in requires that one can identify and exclude a substantial number of treatment intolerant or otherwise unresponsive subjects.

  5. The future of financing for long-term care: the Own Your Future campaign.

    PubMed

    Iwasaki, Michiko; McCurry, Susan M; Borson, Soo; Jones, James A

    2010-10-01

    The purpose of this study was to examine the outreach effort and impact of a joint federal-state campaign, Own Your Future, promoting awareness and planning for long-term care (LTC) in the state of Washington. The study applied survey methodology to evaluate the extent of campaign dissemination, evidence of its impact on LTC planning behaviors, and barriers to purchasing private LTC insurance. A total of 3,198 survey responses from a randomly selected community sample and a Washington State employee sample (ages 51 to 71) were analyzed. Results indicated that the impact of the campaign was limited, both with respect to awareness of the campaign itself and to initiation of LTC planning behaviors. Quantitative data revealed a high prevalence of health-related problems (e.g., obesity, diabetes), inadequate knowledge of basic LTC-related information (e.g., cost, payers), and negative attitudes toward purchasing LTC insurance among respondents. Qualitative analyses suggested that respondents perceived significant problems related to affordability and accountability within the current LTC insurance industry. These possible barriers to the purchase of LTC insurance suggest targets to be addressed by policy makers seeking to find ways to offset the public costs of LTC.

  6. A randomized trial of planned cesarean or vaginal delivery for twin pregnancy.

    PubMed

    Barrett, Jon F R; Hannah, Mary E; Hutton, Eileen K; Willan, Andrew R; Allen, Alexander C; Armson, B Anthony; Gafni, Amiram; Joseph, K S; Mason, Dalah; Ohlsson, Arne; Ross, Susan; Sanchez, J Johanna; Asztalos, Elizabeth V

    2013-10-03

    Twin birth is associated with a higher risk of adverse perinatal outcomes than singleton birth. It is unclear whether planned cesarean section results in a lower risk of adverse outcomes than planned vaginal delivery in twin pregnancy. We randomly assigned women between 32 weeks 0 days and 38 weeks 6 days of gestation with twin pregnancy and with the first twin in the cephalic presentation to planned cesarean section or planned vaginal delivery with cesarean only if indicated. Elective delivery was planned between 37 weeks 5 days and 38 weeks 6 days of gestation. The primary outcome was a composite of fetal or neonatal death or serious neonatal morbidity, with the fetus or infant as the unit of analysis for the statistical comparison. A total of 1398 women (2795 fetuses) were randomly assigned to planned cesarean delivery and 1406 women (2812 fetuses) to planned vaginal delivery. The rate of cesarean delivery was 90.7% in the planned-cesarean-delivery group and 43.8% in the planned-vaginal-delivery group. Women in the planned-cesarean-delivery group delivered earlier than did those in the planned-vaginal-delivery group (mean number of days from randomization to delivery, 12.4 vs. 13.3; P=0.04). There was no significant difference in the composite primary outcome between the planned-cesarean-delivery group and the planned-vaginal-delivery group (2.2% and 1.9%, respectively; odds ratio with planned cesarean delivery, 1.16; 95% confidence interval, 0.77 to 1.74; P=0.49). In twin pregnancy between 32 weeks 0 days and 38 weeks 6 days of gestation, with the first twin in the cephalic presentation, planned cesarean delivery did not significantly decrease or increase the risk of fetal or neonatal death or serious neonatal morbidity, as compared with planned vaginal delivery. (Funded by the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00187369; Current Controlled Trials number, ISRCTN74420086.).

  7. A dose optimization method for electron radiotherapy using randomized aperture beams

    NASA Astrophysics Data System (ADS)

    Engel, Konrad; Gauer, Tobias

    2009-09-01

    The present paper describes the entire optimization process of creating a radiotherapy treatment plan for advanced electron irradiation. Special emphasis is devoted to the selection of beam incidence angles and beam energies as well as to the choice of appropriate subfields generated by a refined version of intensity segmentation and a novel random aperture approach. The algorithms have been implemented in a stand-alone programme using dose calculations from a commercial treatment planning system. For this study, the treatment planning system Pinnacle from Philips has been used and connected to the optimization programme using an ASCII interface. Dose calculations in Pinnacle were performed by Monte Carlo simulations for a remote-controlled electron multileaf collimator (MLC) from Euromechanics. As a result, treatment plans for breast cancer patients could be significantly improved when using randomly generated aperture beams. The combination of beams generated through segmentation and randomization achieved the best results in terms of target coverage and sparing of critical organs. The treatment plans could be further improved by use of a field reduction algorithm. Without a relevant loss in dose distribution, the total number of MLC fields and monitor units could be reduced by up to 20%. In conclusion, using randomized aperture beams is a promising new approach in radiotherapy and exhibits potential for further improvements in dose optimization through a combination of randomized electron and photon aperture beams.

  8. The association between quality of care and the intensity of diabetes disease management programs.

    PubMed

    Mangione, Carol M; Gerzoff, Robert B; Williamson, David F; Steers, W Neil; Kerr, Eve A; Brown, Arleen F; Waitzfelder, Beth E; Marrero, David G; Dudley, R Adams; Kim, Catherine; Herman, William; Thompson, Theodore J; Safford, Monika M; Selby, Joe V

    2006-07-18

    Although disease management programs are widely implemented, little is known about their effectiveness. To determine whether disease management by physician groups is associated with diabetes care processes, control of intermediate outcomes, or the amount of medication used when intermediate outcomes are above target levels. Cross-sectional study. Patients were randomly sampled from 63 physician groups nested in 7 health plans sponsored by Translating Research into Action for Diabetes (87%) and from 4 health plans with individual physician contracts (13%). 8661 adults with diabetes who completed a survey (2000-2001) and had medical record data. Physician group and health plan directors described their organizations' use of physician reminders, performance feedback, and structured care management on a survey; their responses were used to determine measures of intensity of disease management. The current study measured 8 processes of care, including most recent hemoglobin A1c level, systolic blood pressure, serum low-density lipoprotein cholesterol level, and several measures of medication use. Increased use of any of 3 disease management strategies was significantly associated with higher adjusted rates of retinal screening, nephropathy screening, foot examinations, and measurement of hemoglobin A1c levels. Serum lipid level testing and influenza vaccine administration were associated with greater use of structured care management and performance feedback. Greater use of performance feedback correlated with an increased rate of foot examinations (difference, 5 percentage points [95% CI, 1 to 8 percentage points]), and greater use of physician reminders was associated with an increased rate of nephropathy screening (difference, 15 percentage points [CI, 6 to 23 percentage points]). No strategies were associated with intermediate outcome levels or level of medication management. Physician groups were not randomly sampled from population-based listings, and disease management strategies were not randomly allocated across groups. Disease management strategies were associated with better processes of diabetes care but not with improved intermediate outcomes or level of medication management. A greater focus on direct measurement, feedback, and reporting of intermediate outcome levels or of level of medication management may enhance the effectiveness of these programs.

  9. Space shuttle solid rocket booster recovery system definition, volume 1

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The performance requirements, preliminary designs, and development program plans for an airborne recovery system for the space shuttle solid rocket booster are discussed. The analyses performed during the study phase of the program are presented. The basic considerations which established the system configuration are defined. A Monte Carlo statistical technique using random sampling of the probability distribution for the critical water impact parameters was used to determine the failure probability of each solid rocket booster component as functions of impact velocity and component strength capability.

  10. Family emergency preparedness plans in severe tornadoes.

    PubMed

    Cong, Zhen; Liang, Daan; Luo, Jianjun

    2014-01-01

    Tornadoes, with warnings usually issued just minutes before their touchdowns, pose great threats to properties and people's physical and mental health. Few studies have empirically investigated the association of family emergency preparedness planning and observed protective behaviors in the context of tornadoes. The purpose of this study was to examine predictors for the action of taking shelter at the time of tornadoes. Specifically, this study investigated whether having a family emergency preparedness plan was associated with higher likelihood of taking shelter upon receiving tornado warnings. This study also examined the effects of socioeconomic status and functional limitations on taking such actions. A telephone survey based on random sampling was conducted in 2012 with residents in Tuscaloosa AL and Joplin MO. Each city experienced considerable damages, injuries, and casualties after severe tornadoes (EF-4 and EF-5) in 2011. The working sample included 892 respondents. Analysis was conducted in early 2013. Logistic regression identified emergency preparedness planning as the only shared factor that increased the likelihood of taking shelter in both cities and the only significant factor in Joplin. In Tuscaloosa, being female and white also increased the likelihood of taking shelter. Disability was not found to have an effect. This study provided empirical evidence on the importance of having a family emergency preparedness plan in mitigating the risk of tornadoes. The findings could be applied to other rapid-onset disasters. © 2013 American Journal of Preventive Medicine Published by American Journal of Preventive Medicine All rights reserved.

  11. A comparative study on managers', staffs' and clients' viewpoints about organizational and structural obstacles in family planning counseling in health-care centers in Isfahan in 2012.

    PubMed

    Taheri, Safoura; Ehsanpour, Soheila; Kohan, Shahnaz

    2014-03-01

    Organizational and structural obstacles are a group of major obstacles in achievement of appropriate family planning counseling. Detection of these obstacles from the viewpoint of managers, staffs and clients who are key members in health services providing system is a major step toward appropriate planning to modify or delete this group of obstacles. The present study was conducted with the goal of comparing managers', staffs' and clients' viewpoints about organizational and structural obstacles in family planning counseling in health-care centers in Isfahan in 2012. This is a cross-sectional one-step three-group comparative descriptive study conducted on 295 subjects including 59 managers, 110 staffs and 126 clients in medical health-care centers in Isfahan in 2012. Managers and the staffs were selected by census sampling and the clients were recruited through convenient random sampling. The date collection tool was a researcher made questionnaire, which was designed in two sections of fertility and personal characteristics and viewpoint measurement. Descriptive and inferential statistical test were used to analyze the data. The obtained results showed no significant difference between mean scores of viewpoints in three groups of managers, staffs and clients concerning organizational and structural obstacles in family planning counseling (P = 0.677). In addition, most of the managers, staffs and clients reported organizational and structural obstacles as the obstacles in the process of family planning in moderate level. The results showed the necessity of health services managers' planning to modify or delete organizational and structural obstacles especially the agreed obstacles from the viewpoint of managers, staffs and clients.

  12. Implementing an Advance Care Planning Intervention in Community Settings with Older Latinos: A Feasibility Study.

    PubMed

    Nedjat-Haiem, Frances R; Carrion, Iraida V; Gonzalez, Krystyna; Quintana, Alejandra; Ell, Kathleen; O'Connell, Mary; Thompson, Beti; Mishra, Shiraz I

    2017-09-01

    Older Latinos with serious medical conditions such as cancer and other chronic diseases lack information about advance care planning (ACP). ACP Intervention (ACP-I Plan) was designed for informational and communication needs of older Latinos to improve communication and advance directives (ADs). To determine the feasibility of implementing ACP-I Plan among seriously ill, older Latinos (≥50 years) in Southern New Mexico with one or more chronic diseases (e.g., cancer, heart disease, renal/liver failure, stroke, hypertension, diabetes, chronic obstructive pulmonary disease, and HIV/AIDS). We conducted a prospective, pretest/post-test, two-group, randomized, community-based pilot trial by using mixed data collection methods. Older Latino/Hispanic participants were recruited from community-based settings in Southern New Mexico. All participants received ACP education, whereas the intervention group added: (1) emotional support addressing psychological distress; and (2) systems navigation for resource access, all of which included interactive ACP treatment decisional support and involved motivational interview (MI) methods. Purposive sampling was guided by a sociocultural framework to recruit Latino participants from community-based settings in Southern New Mexico. Feasibility of sample recruitment, implementation, and retention was assessed by examining the following: recruitment strategies, trial enrollment, retention rates, duration of MI counseling, type of visit (home vs. telephone), and satisfaction with the program. We contacted 104 patients, enrolled 74 randomized to usual care 39 (UC) and treatment 35 (TX) groups. Six dropped out before the post-test survey, three from TX before the post-test survey because of sickness (n = 1) or could not be located (n = 2), and the same happened for UC. Completion rates were 91.4% UC and 92.3% TX groups. All participants were Latino/Hispanic, born in the United States (48%) or Mexico (51.4%) on average in the United States for 25 years; majority were female, 76.5%; 48.6% preferred Spanish; and 31.4% had less than sixth-grade education. Qualitative data indicate satisfaction with the ACP-I Plan intervention. Based on enrollment and intervention completion rates, time to completion tests, and feedback from qualitative post-study, follow-up interviews, the ACP-I Plan was demonstrated to be feasible and perceived as extremely helpful.

  13. An Experimental Evaluation of Competing Age-Predictions of Future Time Perspective between Workplace and Retirement Domains

    PubMed Central

    Kerry, Matthew J.; Embretson, Susan E.

    2018-01-01

    Future time perspective (FTP) is defined as “perceptions of the future as being limited or open-ended” (Lang and Carstensen, 2002; p. 125). The construct figures prominently in both workplace and retirement domains, but the age-predictions are competing: Workplace research predicts decreasing FTP age-change, in contrast, retirement scholars predict increasing FTP age-change. For the first time, these competing predictions are pitted in an experimental manipulation of subjective life expectancy (SLE). A sample of N = 207 older adults (age 45–60) working full-time (>30-h/week) were randomly assigned to SLE questions framed as either ‘Live-to’ or ‘Die-by’ to evaluate competing predictions for FTP. Results indicate general support for decreasing age-change in FTP, indicated by independent-sample t-tests showing lower FTP in the ‘Die-by’ framing condition. Further general-linear model analyses were conducted to test for interaction effects of retirement planning with experimental framings on FTP and intended retirement; While retirement planning buffered FTP’s decrease, simple-effects also revealed that retirement planning increased intentions for sooner retirement, but lack of planning increased intentions for later retirement. Discussion centers on practical implications of our findings and consequences validity evidence in future empirical research of FTP in both workplace and retirement domains. PMID:29375435

  14. Which food-related behaviours are associated with healthier intakes of fruits and vegetables among women?

    PubMed

    Crawford, David; Ball, Kylie; Mishra, Gita; Salmon, Jo; Timperio, Anna

    2007-03-01

    To examine associations between shopping, food preparation, meal and eating behaviours and fruit and vegetable intake among women. Cross-sectional survey. Community-based sample from metropolitan Melbourne, Australia. A sample of 1136 women aged 18-65 years, randomly selected from the electoral roll. Food-related behaviours reflecting organisation and forward-planning, as well as enjoyment of and high perceived value of meal shopping, preparation and consumption were associated with healthier intakes of fruits and vegetables. For example, women who more frequently planned meals before they went shopping, wrote a shopping list, enjoyed food shopping, planned in the morning what they will eat for dinner that night, planned what they will eat for lunch, reported they enjoy cooking, liked trying new recipes and who reported they sometimes prepare dishes ahead of time were more likely to consume two or more servings of vegetables daily. Conversely, women who frequently found cooking a chore, spent less than 15 minutes preparing dinner, decided on the night what they will eat for dinner, ate in a fast-food restaurant, ate takeaway meals from a fast-food restaurant, ate dinner and snacks while watching television and who frequently ate on the run were less likely to eat two or more servings of vegetables daily. Practical strategies based on these behavioural characteristics could be trialled in interventions aimed at promoting fruit and vegetable consumption among women.

  15. Stable and efficient retrospective 4D-MRI using non-uniformly distributed quasi-random numbers

    NASA Astrophysics Data System (ADS)

    Breuer, Kathrin; Meyer, Cord B.; Breuer, Felix A.; Richter, Anne; Exner, Florian; Weng, Andreas M.; Ströhle, Serge; Polat, Bülent; Jakob, Peter M.; Sauer, Otto A.; Flentje, Michael; Weick, Stefan

    2018-04-01

    The purpose of this work is the development of a robust and reliable three-dimensional (3D) Cartesian imaging technique for fast and flexible retrospective 4D abdominal MRI during free breathing. To this end, a non-uniform quasi random (NU-QR) reordering of the phase encoding (k y –k z ) lines was incorporated into 3D Cartesian acquisition. The proposed sampling scheme allocates more phase encoding points near the k-space origin while reducing the sampling density in the outer part of the k-space. Respiratory self-gating in combination with SPIRiT-reconstruction is used for the reconstruction of abdominal data sets in different respiratory phases (4D-MRI). Six volunteers and three patients were examined at 1.5 T during free breathing. Additionally, data sets with conventional two-dimensional (2D) linear and 2D quasi random phase encoding order were acquired for the volunteers for comparison. A quantitative evaluation of image quality versus scan times (from 70 s to 626 s) for the given sampling schemes was obtained by calculating the normalized mutual information (NMI) for all volunteers. Motion estimation was accomplished by calculating the maximum derivative of a signal intensity profile of a transition (e.g. tumor or diaphragm). The 2D non-uniform quasi-random distribution of phase encoding lines in Cartesian 3D MRI yields more efficient undersampling patterns for parallel imaging compared to conventional uniform quasi-random and linear sampling. Median NMI values of NU-QR sampling are the highest for all scan times. Therefore, within the same scan time 4D imaging could be performed with improved image quality. The proposed method allows for the reconstruction of motion artifact reduced 4D data sets with isotropic spatial resolution of 2.1  ×  2.1  ×  2.1 mm3 in a short scan time, e.g. 10 respiratory phases in only 3 min. Cranio-caudal tumor displacements between 23 and 46 mm could be observed. NU-QR sampling enables for stable 4D-MRI with high temporal and spatial resolution within short scan time for visualization of organ or tumor motion during free breathing. Further studies, e.g. the application of the method for radiotherapy planning are needed to investigate the clinical applicability and diagnostic value of the approach.

  16. Design and analysis of group-randomized trials in cancer: A review of current practices.

    PubMed

    Murray, David M; Pals, Sherri L; George, Stephanie M; Kuzmichev, Andrey; Lai, Gabriel Y; Lee, Jocelyn A; Myles, Ranell L; Nelson, Shakira M

    2018-06-01

    The purpose of this paper is to summarize current practices for the design and analysis of group-randomized trials involving cancer-related risk factors or outcomes and to offer recommendations to improve future trials. We searched for group-randomized trials involving cancer-related risk factors or outcomes that were published or online in peer-reviewed journals in 2011-15. During 2016-17, in Bethesda MD, we reviewed 123 articles from 76 journals to characterize their design and their methods for sample size estimation and data analysis. Only 66 (53.7%) of the articles reported appropriate methods for sample size estimation. Only 63 (51.2%) reported exclusively appropriate methods for analysis. These findings suggest that many investigators do not adequately attend to the methodological challenges inherent in group-randomized trials. These practices can lead to underpowered studies, to an inflated type 1 error rate, and to inferences that mislead readers. Investigators should work with biostatisticians or other methodologists familiar with these issues. Funders and editors should ensure careful methodological review of applications and manuscripts. Reviewers should ensure that studies are properly planned and analyzed. These steps are needed to improve the rigor and reproducibility of group-randomized trials. The Office of Disease Prevention (ODP) at the National Institutes of Health (NIH) has taken several steps to address these issues. ODP offers an online course on the design and analysis of group-randomized trials. ODP is working to increase the number of methodologists who serve on grant review panels. ODP has developed standard language for the Application Guide and the Review Criteria to draw investigators' attention to these issues. Finally, ODP has created a new Research Methods Resources website to help investigators, reviewers, and NIH staff better understand these issues. Published by Elsevier Inc.

  17. [Philanthropic hospitals and the operation of provider-owned health plans in Brazil].

    PubMed

    Lima, Sheyla Maria Lemos; Portela, Margareth C; Ugá, Maria Alicia Dominguez; Barbosa, Pedro Ribeiro; Gerschman, Silvia; Vasconcellos, Miguel Murat

    2007-02-01

    To describe the management performance of philanthropic hospitals that operate their own health plans, in comparison with philanthropic hospitals as a whole in Brazil. The managerial structures of philanthropic hospitals that operated their own health plans were compared with those seen in a representative group from the philanthropic hospital sector, in six dimensions: management and planning, economics and finance, human resources, technical services, logistics services and information technology. Data from a random sample of 69 hospitals within the philanthropic hospital sector and 94 philanthropic hospitals that operate their own health plans were evaluated. In both cases, only the hospitals with less than 599 beds were included. The results identified for the hospitals that operate their own health plans were more positive in all the managerial dimensions compared. In particular, the economics and finance and information technology dimensions were highlighted, for which more than 50% of the hospitals that operated their own health plans presented almost all the conditions considered. The philanthropic hospital sector is important in providing services to the Brazilian Health System (SUS). The challenges in maintaining and developing these hospitals impose the need to find alternatives. Stimulation of a public-private partnership in this segment, by means of operating provider-owned health plans or providing services to other health plans that work together with SUS, is a field that deserves more in-depth analysis.

  18. Association between women's autonomy and family planning outcome in couples residing in Isfahan.

    PubMed

    Kohan, Shahnaz; Talebian, Ferdos; Ehsanpour, Soheila

    2014-09-01

    One of the important factors in the prediction of family planning outcome is paying attention to women's role in decision making concerning fertility and household affairs. With the improvement of women's status and autonomy, their control over fertility is expected to increase. The present study aimed to investigate the association between women's autonomy and family planning outcome of the couples residing in Isfahan. This is cross-sectional study. Two hundred and seventy women of childbearing age, eligible for family planning and residing in Isfahan, were selected through random cluster sampling and they filled a researcher-made questionnaire. Women's autonomy was measured with the questions on their decision-making autonomy concerning household affairs and physical mobility autonomy. The association between women's autonomy and family planning outcome was analyzed through statistical methods. The results showed that the mean of women's decision-making, physical mobility, and general autonomy was 50. Women's autonomy had a direct significant association with the type of contraception method (P = 0.01) and the length of usage of their present contraception method (P = 0.04) as well as where they received family planning services (P = 0.02). Analysis of data revealed women with higher autonomy used a more efficient contraception method and continued their contraception method for a longer time, which leads to improvement of couples' family planning outcome. Therefore, family planning services should be planned and provided with women's autonomy under consideration.

  19. Reporting of sample size calculations in analgesic clinical trials: ACTTION systematic review.

    PubMed

    McKeown, Andrew; Gewandter, Jennifer S; McDermott, Michael P; Pawlowski, Joseph R; Poli, Joseph J; Rothstein, Daniel; Farrar, John T; Gilron, Ian; Katz, Nathaniel P; Lin, Allison H; Rappaport, Bob A; Rowbotham, Michael C; Turk, Dennis C; Dworkin, Robert H; Smith, Shannon M

    2015-03-01

    Sample size calculations determine the number of participants required to have sufficiently high power to detect a given treatment effect. In this review, we examined the reporting quality of sample size calculations in 172 publications of double-blind randomized controlled trials of noninvasive pharmacologic or interventional (ie, invasive) pain treatments published in European Journal of Pain, Journal of Pain, and Pain from January 2006 through June 2013. Sixty-five percent of publications reported a sample size calculation but only 38% provided all elements required to replicate the calculated sample size. In publications reporting at least 1 element, 54% provided a justification for the treatment effect used to calculate sample size, and 24% of studies with continuous outcome variables justified the variability estimate. Publications of clinical pain condition trials reported a sample size calculation more frequently than experimental pain model trials (77% vs 33%, P < .001) but did not differ in the frequency of reporting all required elements. No significant differences in reporting of any or all elements were detected between publications of trials with industry and nonindustry sponsorship. Twenty-eight percent included a discrepancy between the reported number of planned and randomized participants. This study suggests that sample size calculation reporting in analgesic trial publications is usually incomplete. Investigators should provide detailed accounts of sample size calculations in publications of clinical trials of pain treatments, which is necessary for reporting transparency and communication of pre-trial design decisions. In this systematic review of analgesic clinical trials, sample size calculations and the required elements (eg, treatment effect to be detected; power level) were incompletely reported. A lack of transparency regarding sample size calculations may raise questions about the appropriateness of the calculated sample size. Copyright © 2015 American Pain Society. All rights reserved.

  20. Methods and analysis of realizing randomized grouping.

    PubMed

    Hu, Liang-Ping; Bao, Xiao-Lei; Wang, Qi

    2011-07-01

    Randomization is one of the four basic principles of research design. The meaning of randomization includes two aspects: one is to randomly select samples from the population, which is known as random sampling; the other is to randomly group all the samples, which is called randomized grouping. Randomized grouping can be subdivided into three categories: completely, stratified and dynamically randomized grouping. This article mainly introduces the steps of complete randomization, the definition of dynamic randomization and the realization of random sampling and grouping by SAS software.

  1. Transfusion Indication Threshold Reduction (TITRe2) randomized controlled trial in cardiac surgery: statistical analysis plan.

    PubMed

    Pike, Katie; Nash, Rachel L; Murphy, Gavin J; Reeves, Barnaby C; Rogers, Chris A

    2015-02-22

    The Transfusion Indication Threshold Reduction (TITRe2) trial is the largest randomized controlled trial to date to compare red blood cell transfusion strategies following cardiac surgery. This update presents the statistical analysis plan, detailing how the study will be analyzed and presented. The statistical analysis plan has been written following recommendations from the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use, prior to database lock and the final analysis of trial data. Outlined analyses are in line with the Consolidated Standards of Reporting Trials (CONSORT). The study aims to randomize 2000 patients from 17 UK centres. Patients are randomized to either a restrictive (transfuse if haemoglobin concentration <7.5 g/dl) or liberal (transfuse if haemoglobin concentration <9 g/dl) transfusion strategy. The primary outcome is a binary composite outcome of any serious infectious or ischaemic event in the first 3 months following randomization. The statistical analysis plan details how non-adherence with the intervention, withdrawals from the study, and the study population will be derived and dealt with in the analysis. The planned analyses of the trial primary and secondary outcome measures are described in detail, including approaches taken to deal with multiple testing, model assumptions not being met and missing data. Details of planned subgroup and sensitivity analyses and pre-specified ancillary analyses are given, along with potential issues that have been identified with such analyses and possible approaches to overcome such issues. ISRCTN70923932 .

  2. Effect of strategic planning education on attitudes and perceptions of independent community pharmacy owners/managers.

    PubMed

    Harrison, Donald L

    2007-01-01

    To assess the impact of formal education program participation on the attitudes and perceptions of independent community pharmacy owners/managers toward strategic planning. Cross-sectional study. United States; June 4-July 30, 2004. Nationwide random sample of 1,250 owners/managers of independent community pharmacies. Mailed survey. Strategic planning formal education program participation. Comprehensiveness of strategic planning. Attitudes and perceptions of owners/managers of independent community pharmacies toward strategic planning. A total of 527 (42.1%) usable questionnaires were returned. Only 124 (23.5%) respondents indicated that they participated in a formal strategic planning education program. However, of the 141 (26.85%) respondents who indicated that they had conducted strategic planning for their community pharmacy, 111 (89.5%) had participated in a formal strategic planning education program. A significant association was detected between formal education program participation and the conducting of strategic planning (P< or =0.0001). Significant differences were observed for all attitudes and perceptions of independent community pharmacy owners/managers toward strategic planning based on program participation (P< or =0.0001). Finally, respondents who indicated that they had participated in a formal education program had a significantly higher comprehensiveness of strategic planning rating than those respondents who did not participate in an educational program (P< or =0.0001). A significant association exists between formal strategic planning education program participation and the conducting of strategic planning by owner/managers of independent community pharmacies, and those participating in such programs have significantly different attitudes and perceptions toward the conducting of strategic planning and have a significantly higher comprehensiveness of strategic planning rating.

  3. Reliability analysis in the Office of Safety, Environmental, and Mission Assurance (OSEMA)

    NASA Astrophysics Data System (ADS)

    Kauffmann, Paul J.

    1994-12-01

    The technical personnel in the SEMA office are working to provide the highest degree of value-added activities to their support of the NASA Langley Research Center mission. Management perceives that reliability analysis tools and an understanding of a comprehensive systems approach to reliability will be a foundation of this change process. Since the office is involved in a broad range of activities supporting space mission projects and operating activities (such as wind tunnels and facilities), it was not clear what reliability tools the office should be familiar with and how these tools could serve as a flexible knowledge base for organizational growth. Interviews and discussions with the office personnel (both technicians and engineers) revealed that job responsibilities ranged from incoming inspection to component or system analysis to safety and risk. It was apparent that a broad base in applied probability and reliability along with tools for practical application was required by the office. A series of ten class sessions with a duration of two hours each was organized and scheduled. Hand-out materials were developed and practical examples based on the type of work performed by the office personnel were included. Topics covered were: Reliability Systems - a broad system oriented approach to reliability; Probability Distributions - discrete and continuous distributions; Sampling and Confidence Intervals - random sampling and sampling plans; Data Analysis and Estimation - Model selection and parameter estimates; and Reliability Tools - block diagrams, fault trees, event trees, FMEA. In the future, this information will be used to review and assess existing equipment and processes from a reliability system perspective. An analysis of incoming materials sampling plans was also completed. This study looked at the issues associated with Mil Std 105 and changes for a zero defect acceptance sampling plan.

  4. Reliability analysis in the Office of Safety, Environmental, and Mission Assurance (OSEMA)

    NASA Technical Reports Server (NTRS)

    Kauffmann, Paul J.

    1994-01-01

    The technical personnel in the SEMA office are working to provide the highest degree of value-added activities to their support of the NASA Langley Research Center mission. Management perceives that reliability analysis tools and an understanding of a comprehensive systems approach to reliability will be a foundation of this change process. Since the office is involved in a broad range of activities supporting space mission projects and operating activities (such as wind tunnels and facilities), it was not clear what reliability tools the office should be familiar with and how these tools could serve as a flexible knowledge base for organizational growth. Interviews and discussions with the office personnel (both technicians and engineers) revealed that job responsibilities ranged from incoming inspection to component or system analysis to safety and risk. It was apparent that a broad base in applied probability and reliability along with tools for practical application was required by the office. A series of ten class sessions with a duration of two hours each was organized and scheduled. Hand-out materials were developed and practical examples based on the type of work performed by the office personnel were included. Topics covered were: Reliability Systems - a broad system oriented approach to reliability; Probability Distributions - discrete and continuous distributions; Sampling and Confidence Intervals - random sampling and sampling plans; Data Analysis and Estimation - Model selection and parameter estimates; and Reliability Tools - block diagrams, fault trees, event trees, FMEA. In the future, this information will be used to review and assess existing equipment and processes from a reliability system perspective. An analysis of incoming materials sampling plans was also completed. This study looked at the issues associated with Mil Std 105 and changes for a zero defect acceptance sampling plan.

  5. Efficient design of cluster randomized trials with treatment-dependent costs and treatment-dependent unknown variances.

    PubMed

    van Breukelen, Gerard J P; Candel, Math J J M

    2018-06-10

    Cluster randomized trials evaluate the effect of a treatment on persons nested within clusters, where treatment is randomly assigned to clusters. Current equations for the optimal sample size at the cluster and person level assume that the outcome variances and/or the study costs are known and homogeneous between treatment arms. This paper presents efficient yet robust designs for cluster randomized trials with treatment-dependent costs and treatment-dependent unknown variances, and compares these with 2 practical designs. First, the maximin design (MMD) is derived, which maximizes the minimum efficiency (minimizes the maximum sampling variance) of the treatment effect estimator over a range of treatment-to-control variance ratios. The MMD is then compared with the optimal design for homogeneous variances and costs (balanced design), and with that for homogeneous variances and treatment-dependent costs (cost-considered design). The results show that the balanced design is the MMD if the treatment-to control cost ratio is the same at both design levels (cluster, person) and within the range for the treatment-to-control variance ratio. It still is highly efficient and better than the cost-considered design if the cost ratio is within the range for the squared variance ratio. Outside that range, the cost-considered design is better and highly efficient, but it is not the MMD. An example shows sample size calculation for the MMD, and the computer code (SPSS and R) is provided as supplementary material. The MMD is recommended for trial planning if the study costs are treatment-dependent and homogeneity of variances cannot be assumed. © 2018 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.

  6. Reporting funding source or conflict of interest in abstracts of randomized controlled trials, no evidence of a large impact on general practitioners' confidence in conclusions, a three-arm randomized controlled trial.

    PubMed

    Buffel du Vaure, Céline; Boutron, Isabelle; Perrodeau, Elodie; Ravaud, Philippe

    2014-04-28

    Systematic reporting of funding sources is recommended in the CONSORT Statement for abstracts. However, no specific recommendation is related to the reporting of conflicts of interest (CoI). The objective was to compare physicians' confidence in the conclusions of abstracts of randomized controlled trials of pharmaceutical treatment indexed in PubMed. We planned a three-arm parallel-group randomized trial. French general practitioners (GPs) were invited to participate and were blinded to the study's aim. We used a representative sample of 75 abstracts of pharmaceutical industry-funded randomized controlled trials published in 2010 and indexed in PubMed. Each abstract was standardized and reported in three formats: 1) no mention of the funding source or CoI; 2) reporting the funding source only; and 3) reporting the funding source and CoI. GPs were randomized according to a computerized randomization on a secure Internet system at a 1:1:1 ratio to assess one abstract among the three formats. The primary outcome was GPs' confidence in the abstract conclusions (0, not at all, to 10, completely confident). The study was planned to detect a large difference with an effect size of 0.5. Between October 2012 and June 2013, among 605 GPs contacted, 354 were randomized, 118 for each type of abstract. The mean difference (95% confidence interval) in GPs' confidence in abstract findings was 0.2 (-0.6; 1.0) (P = 0.84) for abstracts reporting the funding source only versus no funding source or CoI; -0.4 (-1.3; 0.4) (P = 0.39) for abstracts reporting the funding source and CoI versus no funding source and CoI; and -0.6 (-1.5; 0.2) (P = 0.15) for abstracts reporting the funding source and CoI versus the funding source only. We found no evidence of a large impact of trial report abstracts mentioning funding sources or CoI on GPs' confidence in the conclusions of the abstracts. ClinicalTrials.gov identifier: NCT01679873.

  7. Optimal sample sizes for the design of reliability studies: power consideration.

    PubMed

    Shieh, Gwowen

    2014-09-01

    Intraclass correlation coefficients are used extensively to measure the reliability or degree of resemblance among group members in multilevel research. This study concerns the problem of the necessary sample size to ensure adequate statistical power for hypothesis tests concerning the intraclass correlation coefficient in the one-way random-effects model. In view of the incomplete and problematic numerical results in the literature, the approximate sample size formula constructed from Fisher's transformation is reevaluated and compared with an exact approach across a wide range of model configurations. These comprehensive examinations showed that the Fisher transformation method is appropriate only under limited circumstances, and therefore it is not recommended as a general method in practice. For advance design planning of reliability studies, the exact sample size procedures are fully described and illustrated for various allocation and cost schemes. Corresponding computer programs are also developed to implement the suggested algorithms.

  8. The Danish National Health Survey 2010. Study design and respondent characteristics.

    PubMed

    Christensen, Anne Illemann; Ekholm, Ola; Glümer, Charlotte; Andreasen, Anne Helms; Hvidberg, Michael Falk; Kristensen, Peter Lund; Larsen, Finn Breinholt; Ortiz, Britta; Juel, Knud

    2012-06-01

    In 2010 the five Danish regions and the National Institute of Public Health at the University of Southern Denmark conducted a national representative health survey among the adult population in Denmark. This paper describes the study design and the sample and study population as well as the content of the questionnaire. The survey was based on five regional stratified random samples and one national random sample. The samples were mutually exclusive. A total of 298,550 individuals (16 years or older) were invited to participate. Information was collected using a mixed mode approach (paper and web questionnaires). A questionnaire with a minimum of 52 core questions was used in all six subsamples. Calibrated weights were computed in order to take account of the complex survey design and reduce non-response bias. In all, 177,639 individuals completed the questionnaire (59.5%). The response rate varied from 52.3% in the Capital Region of Denmark sample to 65.5% in the North Denmark Region sample. The response rate was particularly low among young men, unmarried people and among individuals with a different ethnic background than Danish. The survey was a result of extensive national cooperation across sectors, which makes it unique in its field of application, e.g. health surveillance, planning and prioritizing public health initiatives and research. However, the low response rate in some subgroups of the study population can pose problems in generalizing data, and efforts to increase the response rate will be important in the forthcoming surveys.

  9. Marketing family planning services in New Orleans.

    PubMed

    Bertrand, J T; Proffitt, B J; Bartlett, T L

    1987-01-01

    The health care profession is witnessing a shift in focus from the interests and needs of the service provider to those of the potential consumer in an effort to attract and maintain clients. This study illustrates the role that marketing research can play in the development of program strategies, even for relatively small organizations. The study was conducted for Planned Parenthood of Louisiana, a recently organized affiliate that began offering clinical services in May 1984, to provide information on the four Ps of marketing: product, price, place, and promotion. Data from telephone interviews among a random sample of 1,000 women 15-35 years old in New Orleans before the clinic opened confirmed that the need for family planning services was not entirely satisfied by existing service providers. Moreover, it indicated that clinic hours and the cost of services were in line with client interests. The most useful findings for developing the promotional strategy were the relatively low name recognition of Planned Parenthood and a higher-than-expected level of interest that young, low income blacks expressed in using the service.

  10. Marketing family planning services in New Orleans.

    PubMed Central

    Bertrand, J T; Proffitt, B J; Bartlett, T L

    1987-01-01

    The health care profession is witnessing a shift in focus from the interests and needs of the service provider to those of the potential consumer in an effort to attract and maintain clients. This study illustrates the role that marketing research can play in the development of program strategies, even for relatively small organizations. The study was conducted for Planned Parenthood of Louisiana, a recently organized affiliate that began offering clinical services in May 1984, to provide information on the four Ps of marketing: product, price, place, and promotion. Data from telephone interviews among a random sample of 1,000 women 15-35 years old in New Orleans before the clinic opened confirmed that the need for family planning services was not entirely satisfied by existing service providers. Moreover, it indicated that clinic hours and the cost of services were in line with client interests. The most useful findings for developing the promotional strategy were the relatively low name recognition of Planned Parenthood and a higher-than-expected level of interest that young, low income blacks expressed in using the service. PMID:3112854

  11. Vehicle classification in WAMI imagery using deep network

    NASA Astrophysics Data System (ADS)

    Yi, Meng; Yang, Fan; Blasch, Erik; Sheaff, Carolyn; Liu, Kui; Chen, Genshe; Ling, Haibin

    2016-05-01

    Humans have always had a keen interest in understanding activities and the surrounding environment for mobility, communication, and survival. Thanks to recent progress in photography and breakthroughs in aviation, we are now able to capture tens of megapixels of ground imagery, namely Wide Area Motion Imagery (WAMI), at multiple frames per second from unmanned aerial vehicles (UAVs). WAMI serves as a great source for many applications, including security, urban planning and route planning. These applications require fast and accurate image understanding which is time consuming for humans, due to the large data volume and city-scale area coverage. Therefore, automatic processing and understanding of WAMI imagery has been gaining attention in both industry and the research community. This paper focuses on an essential step in WAMI imagery analysis, namely vehicle classification. That is, deciding whether a certain image patch contains a vehicle or not. We collect a set of positive and negative sample image patches, for training and testing the detector. Positive samples are 64 × 64 image patches centered on annotated vehicles. We generate two sets of negative images. The first set is generated from positive images with some location shift. The second set of negative patches is generated from randomly sampled patches. We also discard those patches if a vehicle accidentally locates at the center. Both positive and negative samples are randomly divided into 9000 training images and 3000 testing images. We propose to train a deep convolution network for classifying these patches. The classifier is based on a pre-trained AlexNet Model in the Caffe library, with an adapted loss function for vehicle classification. The performance of our classifier is compared to several traditional image classifier methods using Support Vector Machine (SVM) and Histogram of Oriented Gradient (HOG) features. While the SVM+HOG method achieves an accuracy of 91.2%, the accuracy of our deep network-based classifier reaches 97.9%.

  12. 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.

  13. Facilitating sunscreen use in women by a theory-based online intervention: a randomized controlled trial.

    PubMed

    Craciun, Catrinel; Schüz, Natalie; Lippke, Sonia; Schwarzer, Ralf

    2012-03-01

    This study compares a motivational skin cancer prevention approach with a volitional planning and self-efficacy intervention to enhance regular sunscreen use. A randomized controlled trial (RCT) was conducted with 205 women (mean age 25 years) in three groups: motivational; volitional; and control. Sunscreen use, action planning, coping planning and coping self-efficacy were assessed at three points in time. The volitional intervention improved sunscreen use. Coping planning emerged as the only mediator between the intervention and sunscreen use at Time 3. Findings point to the role played by coping planning as an ingredient of sun protection interventions.

  14. Medicare Part D Roulette: Potential Implications of Random Assignment and Plan Restrictions

    PubMed Central

    Patel, Rajul A.; Walberg, Mark P.; Woelfel, Joseph A.; Amaral, Michelle M.; Varu, Paresh

    2013-01-01

    Background Dual-eligible (Medicare/Medicaid) beneficiaries are randomly assigned to a benchmark plan, which provides prescription drug coverage under the Part D benefit without consideration of their prescription drug profile. To date, the potential for beneficiary assignment to a plan with poor formulary coverage has been minimally studied and the resultant financial impact to beneficiaries unknown. Objective We sought to determine cost variability and drug use restrictions under each available 2010 California benchmark plan. Methods Dual-eligible beneficiaries were provided Part D plan assistance during the 2010 annual election period. The Medicare Web site was used to determine benchmark plan costs and prescription utilization restrictions for each of the six California benchmark plans available for random assignment in 2010. A standardized survey was used to record all de-identified beneficiary demographic and plan specific data. For each low-income subsidy-recipient (n = 113), cost, rank, number of non-formulary medications, and prescription utilization restrictions were recorded for each available 2010 California benchmark plan. Formulary matching rates (percent of beneficiary's medications on plan formulary) were calculated for each benchmark plan. Results Auto-assigned beneficiaries had only a 34% chance of being assigned to the lowest cost plan; the remainder faced potentially significant avoidable out-of-pocket costs. Wide variations between benchmark plans were observed for plan cost, formulary coverage, formulary matching rates, and prescription utilization restrictions. Conclusions Beneficiaries had a 66% chance of being assigned to a sub-optimal plan; thereby, they faced significant avoidable out-of-pocket costs. Alternative methods of beneficiary assignment could decrease beneficiary and Medicare costs while also reducing medication non-compliance. PMID:24753963

  15. Health plan decision making in the Medicare population: results from a national randomized experiment.

    PubMed

    McCormack, L A; Anderson, W L; Uhrig, J D; Garfinkel, S A; Sofaer, S; Terrell, S A

    2001-12-01

    To examine the effect of providing the Medicare & You handbook on consumers' attitudes and behavior regarding health plan decision making. A national sample of 3,738 Medicare beneficiaries who were surveyed in late 1999 and early 2000 was employed. Data were collected using a mail survey with telephone follow-up; the response rate was 76 percent. Medicare beneficiaries were randomly assigned to a control group that received no Medicare-related in formation as part of the study, or to a treatment group that received a copy of the 2000 version of the Medicare & You handbook as part of a national mailing. Half of the treat men t group (the "re-mail" group) received a second copy of the handbook along wit h their mail survey instrument. The control and treatment groups did not differ regarding their level of satisfaction with or confidence in their current choice of health plan according to predicted mean values. Treatment group beneficiaries had a significantly higher propensity to either change or consider changing health plans relative to beneficiaries in the control group. Controlling for other factors, 5 percent of treatment group members switched health insurance plans during the prior month compared to 3 percent of control group members. there were no significant differences in predicted values between the re-mail and no re-mail groups in any of the models. Type of supplemental insurance was also highly related to all three outcomes. Findings from this and a prior parallel study suggest th at messages contained in the Medicare & You handbook can have an influence on beneficiaries and the Medicare market . Thus, careful attention should be given to the wording and intent of these messages. This is particularly relevant given the current administration's emphasis on increasing enrollment in Medicare+Choice plans and findings from earlier research reporting that beneficiaries felt the handbook was pressuring them to enroll in managed care.

  16. Causal modeling of self-concept, job satisfaction, and retention of nurses.

    PubMed

    Cowin, Leanne S; Johnson, Maree; Craven, Rhonda G; Marsh, Herbert W

    2008-10-01

    The critical shortage of nurses experienced throughout the western world has prompted researchers to examine one major component of this complex problem - the impact of nurses' professional identity and job satisfaction on retention. A descriptive correlational design with a longitudinal element was used to examine a causal model of nurses' self-concept, job satisfaction, and retention plans in 2002. A random sample of 2000 registered nurses was selected from the state registering authority listing. A postal survey assessing multiple dimensions of nurses' self-concept (measured by the nurse self-concept questionnaire), job satisfaction (measured by the index of work satisfaction) was undertaken at Time 1 (n=528) and 8 months later at Time 2 (n=332) (including retention plans (measured by the Nurse Retention Index). Using confirmatory factor analysis, correlation matrices and path analysis, measurement and structural models were examined on matching pairs of data from T1 and T2 (total sample N=332). Nurses' self-concept was found to have a stronger association with nurses' retention plans (B=.45) than job satisfaction (B=.28). Aspects of pay and task were not significantly related to retention plans, however, professional status (r=.51), and to a lesser extent, organizational policies (r=.27) were significant factors. Nurses' general self-concept was strongly related (r=.57) to retention plans. Strategies or interventions requiring implementation and evaluation include: counseling to improve nurse general self-concept, education programs and competencies in health communication between health professionals, reporting of nurse-initiated programs with substantial patient benefit, nurse-friendly organizational policies, common health team learning opportunities, and autonomous practice models.

  17. Path planning in uncertain flow fields using ensemble method

    NASA Astrophysics Data System (ADS)

    Wang, Tong; Le Maître, Olivier P.; Hoteit, Ibrahim; Knio, Omar M.

    2016-10-01

    An ensemble-based approach is developed to conduct optimal path planning in unsteady ocean currents under uncertainty. We focus our attention on two-dimensional steady and unsteady uncertain flows, and adopt a sampling methodology that is well suited to operational forecasts, where an ensemble of deterministic predictions is used to model and quantify uncertainty. In an operational setting, much about dynamics, topography, and forcing of the ocean environment is uncertain. To address this uncertainty, the flow field is parametrized using a finite number of independent canonical random variables with known densities, and the ensemble is generated by sampling these variables. For each of the resulting realizations of the uncertain current field, we predict the path that minimizes the travel time by solving a boundary value problem (BVP), based on the Pontryagin maximum principle. A family of backward-in-time trajectories starting at the end position is used to generate suitable initial values for the BVP solver. This allows us to examine and analyze the performance of the sampling strategy and to develop insight into extensions dealing with general circulation ocean models. In particular, the ensemble method enables us to perform a statistical analysis of travel times and consequently develop a path planning approach that accounts for these statistics. The proposed methodology is tested for a number of scenarios. We first validate our algorithms by reproducing simple canonical solutions, and then demonstrate our approach in more complex flow fields, including idealized, steady and unsteady double-gyre flows.

  18. Quantifying Unnecessary Normal Tissue Complication Risks due to Suboptimal Planning: A Secondary Study of RTOG 0126.

    PubMed

    Moore, Kevin L; Schmidt, Rachel; Moiseenko, Vitali; Olsen, Lindsey A; Tan, Jun; Xiao, Ying; Galvin, James; Pugh, Stephanie; Seider, Michael J; Dicker, Adam P; Bosch, Walter; Michalski, Jeff; Mutic, Sasa

    2015-06-01

    The purpose of this study was to quantify the frequency and clinical severity of quality deficiencies in intensity modulated radiation therapy (IMRT) planning in the Radiation Therapy Oncology Group 0126 protocol. A total of 219 IMRT patients from the high-dose arm (79.2 Gy) of RTOG 0126 were analyzed. To quantify plan quality, we used established knowledge-based methods for patient-specific dose-volume histogram (DVH) prediction of organs at risk and a Lyman-Kutcher-Burman (LKB) model for grade ≥2 rectal complications to convert DVHs into normal tissue complication probabilities (NTCPs). The LKB model was validated by fitting dose-response parameters relative to observed toxicities. The 90th percentile (22 of 219) of plans with the lowest excess risk (difference between clinical and model-predicted NTCP) were used to create a model for the presumed best practices in the protocol (pDVH0126,top10%). Applying the resultant model to the entire sample enabled comparisons between DVHs that patients could have received to DVHs they actually received. Excess risk quantified the clinical impact of suboptimal planning. Accuracy of pDVH predictions was validated by replanning 30 of 219 patients (13.7%), including equal numbers of presumed "high-quality," "low-quality," and randomly sampled plans. NTCP-predicted toxicities were compared to adverse events on protocol. Existing models showed that bladder-sparing variations were less prevalent than rectum quality variations and that increased rectal sparing was not correlated with target metrics (dose received by 98% and 2% of the PTV, respectively). Observed toxicities were consistent with current LKB parameters. Converting DVH and pDVH0126,top10% to rectal NTCPs, we observed 94 of 219 patients (42.9%) with ≥5% excess risk, 20 of 219 patients (9.1%) with ≥10% excess risk, and 2 of 219 patients (0.9%) with ≥15% excess risk. Replanning demonstrated the predicted NTCP reductions while maintaining the volume of the PTV receiving prescription dose. An equivalent sample of high-quality plans showed fewer toxicities than low-quality plans, 6 of 73 versus 10 of 73 respectively, although these differences were not significant (P=.21) due to insufficient statistical power in this retrospective study. Plan quality deficiencies in RTOG 0126 exposed patients to substantial excess risk for rectal complications. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Assessing Emergency Preparedness and Response Capacity Using Community Assessment for Public Health Emergency Response Methodology: Portsmouth, Virginia, 2013.

    PubMed

    Kurkjian, Katie M; Winz, Michelle; Yang, Jun; Corvese, Kate; Colón, Ana; Levine, Seth J; Mullen, Jessica; Ruth, Donna; Anson-Dwamena, Rexford; Bayleyegn, Tesfaye; Chang, David S

    2016-04-01

    For the past decade, emergency preparedness campaigns have encouraged households to meet preparedness metrics, such as having a household evacuation plan and emergency supplies of food, water, and medication. To estimate current household preparedness levels and to enhance disaster response planning, the Virginia Department of Health with remote technical assistance from the Centers for Disease Control and Prevention conducted a community health assessment in 2013 in Portsmouth, Virginia. Using the Community Assessment for Public Health Emergency Response (CASPER) methodology with 2-stage cluster sampling, we randomly selected 210 households for in-person interviews. Households were questioned about emergency planning and supplies, information sources during emergencies, and chronic health conditions. Interview teams completed 180 interviews (86%). Interviews revealed that 70% of households had an emergency evacuation plan, 67% had a 3-day supply of water for each member, and 77% had a first aid kit. Most households (65%) reported that the television was the primary source of information during an emergency. Heart disease (54%) and obesity (40%) were the most frequently reported chronic conditions. The Virginia Department of Health identified important gaps in local household preparedness. Data from the assessment have been used to inform community health partners, enhance disaster response planning, set community health priorities, and influence Portsmouth's Community Health Improvement Plan.

  20. Using choice-based conjoint to determine the relative importance of dental benefit plan attributes.

    PubMed

    Cunningham, M A; Gaeth, G J; Juang, C; Chakraborty, G

    1999-05-01

    The purpose of this study was to use conjoint analysis to determine the importance of specific dental benefit plan features for University of Iowa (UI) staff and to build a model to predict enrollment. From a random sample of 2000 UI staff, 40 percent responded (N = 773). The survey instrument was developed using seven attributes (five dental benefit plan features and two facility characteristics) each offered at three levels (e.g., premium = $20, $15, $10/month). Pilot testing was used to find a realistic range of plan options. Twenty-seven hypothetical dental benefit plans were developed using fractional factorial combinations of the three levels for each of the seven attributes. For all of the hypothetical plans, dental care was to be provided in the UI predoctoral dental clinic. Plan profiles were arranged four per page by combining the existing plan with three hypothetical plans, for a total of nine pages. Respondents' task was to select one plan from each set of four. A regression-like statistical model (Multinomial Logit) was used to estimate importance of each attribute and each attribute level. Relative importance (and coefficients) for each of the seven attributes are as follows: maximum annual benefit (.98), orthodontic coverage (.72), routine restorative (.70), major restorative (.67), time to complete treatment (.61), clinic hours of operation (.47), premium (.18). For each attribute, relative importance of each of three levels will also be presented. These coefficients for each level are used to predict enrollment for plans with specific combinations of the dental benefit plan features.

  1. Evaluating hospital discharge planning: a randomized clinical trial.

    PubMed

    Evans, R L; Hendricks, R D

    1993-04-01

    To select patients for early discharge planning, a randomized clinical trial evaluated a protocol that used risk factors identified upon hospital admission. The goal of the study was to determine if intervention with high-risk patients could reduce the need for hospital admission or skilled care. Of 13,255 patients screened, 835 study participants were identified as "at risk" for frequent health care resource use. Half of the high-risk patients were randomly assigned to the experimental group (n = 417) and received discharge planning from day 3 of their hospital stay, while the control group (n = 418) received discharge planning only if there was a written physician request. Those patients receiving early, systematic discharge planning experienced an increased likelihood of successful return to home after hospital admission and a decreased chance of unscheduled readmission for the 9-month study period. Length of the index hospital stay was not affected by early planning, however. The major clinical implication is the potential for discharge planners to decrease the need for, and use of, health care resources after hospital admission.

  2. Interaction between pre- and post-migration factors on depressive symptoms in new migrants to Hong Kong from Mainland China.

    PubMed

    Chou, Kee-Lee; Wong, Winky K F; Chow, Nelson W S

    2011-10-01

    The goal of the current study is to examine the role of poor migration planning as a moderator for the effects of two post-migration factors, namely acculturation stress and quality of life, on symptoms of depression. Using a random sample of 347 Hong Kong new migrants from a 1-year longitudinal study, we used multiple regression analyses to examine both the direct and interaction effects of poorly planned migration, acculturation stress, and quality of life on depressive symptoms. Although poorly planned migration did not predict depressive symptoms at 1-year follow-up, it did exacerbate the detrimental effect of the two post-migration factors, namely high stress or low quality of life (both also measured at baseline) on depressive symptoms at this stage. Our results indicate that preventive measures must be developed for new immigrants in Hong Kong, especially for those who were not well prepared for migration.

  3. Applying the theory of planned behavior to promotion of whole-grain foods by dietitians.

    PubMed

    Chase, Kellie; Reicks, Marla; Jones, Julie Miller

    2003-12-01

    The objective of this preliminary study was to apply the theory of planned behavior to explain dietitians' intentions to promote whole-grain foods. Surveys were mailed to a random national sample of registered dietitians to assess knowledge and attitudinal, normative, and control beliefs regarding intention to promote whole-grain foods, with a 39% return rate (n=776, with 628 usable surveys from those working in direct patient care). About half of the respondents had a master's degree, and 58% had substantial experience in the dietetics field. The theory of planned behavior explained intention to promote whole grains to a moderate extent (df=3, F=74.5, R(2)=0.278, P<.001). Most were positive about the health benefits, and few perceived barriers to promotion. However, many had low levels of knowledge and self-efficacy regarding ability to help clients consume more whole-grain foods. Continuing education for dietitians should use strategies that enhance self-efficacy regarding ability to promote whole-grain foods.

  4. Random-walk mobility analysis of Lisbon's plans for the post-1755 reconstruction

    NASA Astrophysics Data System (ADS)

    de Sampayo, Mafalda Teixeira; Sousa-Rodrigues, David

    2016-11-01

    The different options for the reconstruction of the city of Lisbon in the aftermath of the 1755 earthquake are studied with an agent-based model based on randomwalks. This method gives a comparative quantitative measure of mobility of the circulation spaces within the city. The plans proposed for the city of Lisbon signified a departure from the medieval mobility city model. The intricacy of the old city circulation spaces is greatly reduced in the new plans and the mobility between different areas is substantially improved. The simulation results of the random-walk model show that those plans keeping the main force lines of the old city presented less improvement in terms ofmobility. The plans that had greater design freedom were, by contrast, easier to navigate. Lisbon's reconstruction followed a plan that included a shift in the traditional notions of mobility. This affected the daily lives of its citizens by potentiating an easy access to the waterfront, simplifying orientation and navigability. Using the random-walk model it is shown how to quantitatively measure the potential that synthetic plans have in terms of the permeability and navigability of different city public spaces.

  5. Optimizing occupational exposure measurement strategies when estimating the log-scale arithmetic mean value--an example from the reinforced plastics industry.

    PubMed

    Lampa, Erik G; Nilsson, Leif; Liljelind, Ingrid E; Bergdahl, Ingvar A

    2006-06-01

    When assessing occupational exposures, repeated measurements are in most cases required. Repeated measurements are more resource intensive than a single measurement, so careful planning of the measurement strategy is necessary to assure that resources are spent wisely. The optimal strategy depends on the objectives of the measurements. Here, two different models of random effects analysis of variance (ANOVA) are proposed for the optimization of measurement strategies by the minimization of the variance of the estimated log-transformed arithmetic mean value of a worker group, i.e. the strategies are optimized for precise estimation of that value. The first model is a one-way random effects ANOVA model. For that model it is shown that the best precision in the estimated mean value is always obtained by including as many workers as possible in the sample while restricting the number of replicates to two or at most three regardless of the size of the variance components. The second model introduces the 'shared temporal variation' which accounts for those random temporal fluctuations of the exposure that the workers have in common. It is shown for that model that the optimal sample allocation depends on the relative sizes of the between-worker component and the shared temporal component, so that if the between-worker component is larger than the shared temporal component more workers should be included in the sample and vice versa. The results are illustrated graphically with an example from the reinforced plastics industry. If there exists a shared temporal variation at a workplace, that variability needs to be accounted for in the sampling design and the more complex model is recommended.

  6. An exploratory study of a text classification framework for Internet-based surveillance of emerging epidemics

    PubMed Central

    Torii, Manabu; Yin, Lanlan; Nguyen, Thang; Mazumdar, Chand T.; Liu, Hongfang; Hartley, David M.; Nelson, Noele P.

    2014-01-01

    Purpose Early detection of infectious disease outbreaks is crucial to protecting the public health of a society. Online news articles provide timely information on disease outbreaks worldwide. In this study, we investigated automated detection of articles relevant to disease outbreaks using machine learning classifiers. In a real-life setting, it is expensive to prepare a training data set for classifiers, which usually consists of manually labeled relevant and irrelevant articles. To mitigate this challenge, we examined the use of randomly sampled unlabeled articles as well as labeled relevant articles. Methods Naïve Bayes and Support Vector Machine (SVM) classifiers were trained on 149 relevant and 149 or more randomly sampled unlabeled articles. Diverse classifiers were trained by varying the number of sampled unlabeled articles and also the number of word features. The trained classifiers were applied to 15 thousand articles published over 15 days. Top-ranked articles from each classifier were pooled and the resulting set of 1337 articles was reviewed by an expert analyst to evaluate the classifiers. Results Daily averages of areas under ROC curves (AUCs) over the 15-day evaluation period were 0.841 and 0.836, respectively, for the naïve Bayes and SVM classifier. We referenced a database of disease outbreak reports to confirm that this evaluation data set resulted from the pooling method indeed covered incidents recorded in the database during the evaluation period. Conclusions The proposed text classification framework utilizing randomly sampled unlabeled articles can facilitate a cost-effective approach to training machine learning classifiers in a real-life Internet-based biosurveillance project. We plan to examine this framework further using larger data sets and using articles in non-English languages. PMID:21134784

  7. Analysis of the Habitat of Henslow's Sparrows and Grasshopper Sparrows Compared to Random Grassland Areas

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

    Maier, K.; Walton, R.; Kasper, P.

    2006-01-01

    ABSTRAC T Henslow’s Sparrows are endangered prairie birds, and Grasshopper Sparrows are considered rare prairie birds. Both of these birds were abundant in Illinois, but their populations have been declining due to loss of the grasslands. This begins an ongoing study of the birds’ habitat so Fermilab can develop a land management plan for the Henslow’s and Grasshoppers. The Henslow’s were found at ten sites and Grasshoppers at eight sites. Once the birds were located, the vegetation at their sites was studied. Measurements of the maximum plant height, average plant height, and duff height were taken and estimates of themore » percent of grass, forbs, duff, and bare ground were recorded for each square meter studied. The same measurements were taken at ten random grassland sites on Fermilab property. Several t-tests were performed on the data, and it was found that both Henslow’s Sparrows and Grasshopper Sparrows preferred areas with a larger percentage of grass than random areas. Henslow’s also preferred areas with less bare ground than random areas, while Grasshoppers preferred areas with more bare ground than random areas. In addition, Grasshopper Sparrows preferred a lower percentage of forbs than was found in random areas and a shorter average plant height than the random locations. Two-sample variance tests suggested significantly less variance for both Henslow’s Sparrows and Grasshopper Sparrows for maximum plant height in comparison to the random sites.« less

  8. Improved Compressive Sensing of Natural Scenes Using Localized Random Sampling

    PubMed Central

    Barranca, Victor J.; Kovačič, Gregor; Zhou, Douglas; Cai, David

    2016-01-01

    Compressive sensing (CS) theory demonstrates that by using uniformly-random sampling, rather than uniformly-spaced sampling, higher quality image reconstructions are often achievable. Considering that the structure of sampling protocols has such a profound impact on the quality of image reconstructions, we formulate a new sampling scheme motivated by physiological receptive field structure, localized random sampling, which yields significantly improved CS image reconstructions. For each set of localized image measurements, our sampling method first randomly selects an image pixel and then measures its nearby pixels with probability depending on their distance from the initially selected pixel. We compare the uniformly-random and localized random sampling methods over a large space of sampling parameters, and show that, for the optimal parameter choices, higher quality image reconstructions can be consistently obtained by using localized random sampling. In addition, we argue that the localized random CS optimal parameter choice is stable with respect to diverse natural images, and scales with the number of samples used for reconstruction. We expect that the localized random sampling protocol helps to explain the evolutionarily advantageous nature of receptive field structure in visual systems and suggests several future research areas in CS theory and its application to brain imaging. PMID:27555464

  9. Association between women's autonomy and family planning outcome in couples residing in Isfahan

    PubMed Central

    Kohan, Shahnaz; Talebian, Ferdos; Ehsanpour, Soheila

    2014-01-01

    Background: One of the important factors in the prediction of family planning outcome is paying attention to women's role in decision making concerning fertility and household affairs. With the improvement of women's status and autonomy, their control over fertility is expected to increase. The present study aimed to investigate the association between women's autonomy and family planning outcome of the couples residing in Isfahan. Materials and Methods: This is cross-sectional study. Two hundred and seventy women of childbearing age, eligible for family planning and residing in Isfahan, were selected through random cluster sampling and they filled a researcher-made questionnaire. Women's autonomy was measured with the questions on their decision-making autonomy concerning household affairs and physical mobility autonomy. The association between women's autonomy and family planning outcome was analyzed through statistical methods. Results: The results showed that the mean of women's decision-making, physical mobility, and general autonomy was 50. Women's autonomy had a direct significant association with the type of contraception method (P = 0.01) and the length of usage of their present contraception method (P = 0.04) as well as where they received family planning services (P = 0.02). Conclusions: Analysis of data revealed women with higher autonomy used a more efficient contraception method and continued their contraception method for a longer time, which leads to improvement of couples’ family planning outcome. Therefore, family planning services should be planned and provided with women's autonomy under consideration. PMID:25400671

  10. Gaps, conflicts, and consensus in the ethics statements of professional associations, medical groups, and health plans.

    PubMed

    Berkman, N D; Wynia, M K; Churchill, L R

    2004-08-01

    Patients today interact with physicians, physician groups, and health plans, each of which may follow distinct ethical guidelines. We systematically compared physician codes of ethics with ethics policies at physician group practices and health plans, using the 1998-99 policies of 38 organisations-18 medical associations (associations), nine physician group practices (groups), and 12 health plans (plans)-selected using random and stratified purposive sampling. A clinician and a social scientist independently abstracted each document, using a 397-item health care ethics taxonomy; a reconciled abstraction form was used for analysis. This study focuses on ethics policies regarding professional obligation towards patients, resource allocation, and care for the vulnerable in society. A majority in all three groups mention "fiduciary obligations" of one sort or another, but associations generally address physician/patient relations but not health plan obligations, while plans rarely endorse physicians' obligations of advocacy, beneficence, and non-maleficence. Except for occasional mentions of cost effectiveness or efficiency, ethical considerations in resource allocation rarely arise in the ethics policies of all three organisational types. Very few associations, groups, or plans specifically endorse obligations to vulnerable populations. With some important exceptions, we found that the ethics policies of associations, groups, and plans are narrowly focused and often ignore important ethical concerns for society, such as resource allocation and care for vulnerable populations. More collaborative work is needed to build integrated sets of ethical standards that address the aims and responsibilities of the major stakeholders in health care delivery.

  11. Turning the Waiting Room into a Classroom: Weekly Classes Using a Vegan or a Portion-Controlled Eating Plan Improve Diabetes Control in a Randomized Translational Study.

    PubMed

    Barnard, Neal D; Levin, Susan M; Gloede, Lise; Flores, Rosendo

    2018-06-01

    In research settings, plant-based (vegan) eating plans improve diabetes management, typically reducing weight, glycemia, and low-density lipoprotein (LDL) cholesterol concentrations to a greater extent than has been shown with portion-controlled eating plans. The study aimed to test whether similar benefits could be found using weekly nutrition classes in a typical endocrinology practice, hypothesizing that a vegan eating plan would improve glycemic control, weight, lipid concentrations, blood pressure, and renal function and would do so more effectively than a portion-controlled eating plan. In a 20-week trial, participants were randomly assigned to a low-fat vegan or portion-controlled eating plan. Individuals with type 2 diabetes treated in a single endocrinology practice in Washington, DC, participated (45 starters, 40 completers). Participants attended weekly after-hours classes in the office waiting room. The vegan plan excluded animal products and added oils and favored low-glycemic index foods. The portion-controlled plan included energy intake limits for weight loss (typically a deficit of 500 calories/day) and provided guidance on portion sizes. Body weight, hemoglobin A1c (HbA1c), plasma lipids, urinary albumin, and blood pressure were measured. For normally distributed data, t tests were used; for skewed outcomes, rank-based approaches were implemented (Wilcoxon signed-rank test for within-group changes, Wilcoxon two-sample test for between-group comparisons, and exact Hodges-Lehmann estimation to estimate effect sizes). Although participants were in generally good metabolic control at baseline, body weight, HbA1c, and LDL cholesterol improved significantly within each group, with no significant differences between the two eating plans (weight: -6.3 kg vegan, -4.4 kg portion-controlled, between-group P=0.10; HbA1c, -0.40 percentage point in both groups, P=0.68; LDL cholesterol -11.9 mg/dL vegan, -12.7 mg/dL portion-controlled, P=0.89). Mean urinary albumin was normal at baseline and did not meaningfully change. Blood pressure changes were not significant. Weekly classes, integrated into a clinical practice and using either a low-fat vegan or portion-controlled eating plan, led to clinical improvements in individuals with type 2 diabetes. Copyright © 2018 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  12. 7 CFR 43.104 - Master table of single and double sampling plans.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Master table of single and double sampling plans. 43... STANDARD CONTAINER REGULATIONS STANDARDS FOR SAMPLING PLANS Sampling Plans § 43.104 Master table of single and double sampling plans. (a) In the master table, a sampling plan is selected by first determining...

  13. 7 CFR 43.104 - Master table of single and double sampling plans.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Master table of single and double sampling plans. 43... STANDARD CONTAINER REGULATIONS STANDARDS FOR SAMPLING PLANS Sampling Plans § 43.104 Master table of single and double sampling plans. (a) In the master table, a sampling plan is selected by first determining...

  14. 7 CFR 43.104 - Master table of single and double sampling plans.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Master table of single and double sampling plans. 43... STANDARD CONTAINER REGULATIONS STANDARDS FOR SAMPLING PLANS Sampling Plans § 43.104 Master table of single and double sampling plans. (a) In the master table, a sampling plan is selected by first determining...

  15. 7 CFR 43.104 - Master table of single and double sampling plans.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Master table of single and double sampling plans. 43... STANDARD CONTAINER REGULATIONS STANDARDS FOR SAMPLING PLANS Sampling Plans § 43.104 Master table of single and double sampling plans. (a) In the master table, a sampling plan is selected by first determining...

  16. Quantity and quality of information, education and communication during antenatal visit at private and public sector hospitals of Bahawalpur, Pakistan.

    PubMed

    Mahar, Benazeer; Kumar, Ramesh; Rizvi, Narjis; Bahalkani, Habib Akhtar; Haq, Mahboobul; Soomro, Jamila

    2012-01-01

    Information, education and communication (IEC) by health care provider to pregnant woman during the antenatal visit are very crucial for healthier outcome of pregnancy. This study analysed the quality and quantity of antenatal visit at a private and a public hospital of Bahawalpur, Pakistan. An exit interview was conducted from 216 pregnant women by using validated, reliable and pre-tested adapted questionnaire. First sample was selected by simple random sampling, for rest of the sample selection systematic random sampling was adapted by selecting every 7th women for interview. Ethical considerations were taken. Average communication time among pregnant woman and her healthcare provider was 3 minute in public and 8 minutes in private hospital. IEC mainly focused on diet and nutrition in private (86%) and (53%) public, advice for family planning after delivery was discussed with 13% versus 7% in public and private setting. None of the respondents in both facilities got advice or counselling on breastfeeding and neonatal care. Birth preparedness components were discussed, woman in public and private hospital respectively. In both settings antenatal clients were not received information and education communication according to World Health Organization guidelines. Quality and quantity of IEC during antenatal care was found very poor in both public and private sector hospitals of urban Pakistan.

  17. Willingness to participate and Pay for a proposed national health insurance in St. Vincent and the grenadines: a cross-sectional contingent valuation approach.

    PubMed

    Adams, Rosmond; Chou, Yiing-Jenq; Pu, Christy

    2015-04-09

    Numerous Caribbean countries are considering implementing National Health Insurance (NHI) and pooling resources to finance their health sectors. Based on this increased interest in health insurance, we investigated the willingness to participate and to pay for NHI in St. Vincent and the Grenadines, an upper-middle-income Caribbean country. Four hundred heads of household in St. Vincent and the Grenadines were interviewed in August 2012 and September 2012. The samples were selected through simple random sampling, including the stratification of rural, semiurban, and urban communities to ensure the representativeness of the sample. A contingent valuation method with a pretested interviewer-led questionnaire was used. Respondents were presented with a hypothetical NHI plan. Chi-squared analysis was performed to identify factors that are associated with the willingness to participate. Multiple logistic regression was used to explore the factors that influence respondents' willingness to pay. In total, 69.5% (n = 278) of the respondents indicated that they were willing to participate in the proposed NHI plan, of whom 72.3% were willing to pay for the first bid (EC$50). When the bid was reduced to EC$25, all of the remaining respondents who indicated they were willing to participate were willing to pay this lowered bid. Overall, the respondents were willing to pay EC$77.83 (US$28.83) per month for each person to enroll in the NHI plan. Age, income, and having some form of health insurance were significantly associated with a willingness to participate in the plan. A higher socioeconomic status was the principal determinant factor for the willingness to participate. This is similar to studies on developing economies. The government can use these findings to guide the successful implementation of the proposed NHI program. People with a lower socioeconomic status must be engaged from the start of and throughout the development process to enhance their understanding of and participation in the plan.

  18. A Controlled Trial of Teaching Clinical Biochemistry by the Keller Plan.

    ERIC Educational Resources Information Center

    Schwartz, Peter L.

    1980-01-01

    Thirty medical students at the University of Otago were randomly chosen to learn clinical biochemistry by the Keller Plan. The rest of the class acted as controls. The randomly selected Keller group scored significantly higher than the control group on a practice/review test and the final examination. (Author/MLW)

  19. Dyadic planning of health-behavior change after prostatectomy: a randomized-controlled planning intervention.

    PubMed

    Burkert, Silke; Scholz, Urte; Gralla, Oliver; Roigas, Jan; Knoll, Nina

    2011-09-01

    In this study, we investigated the role of dyadic planning for health-behavior change. Dyadic planning refers to planning health-behavior change together with a partner. We assumed that dyadic planning would affect the implementation of regular pelvic-floor exercise (PFE), with other indicators of social exchange and self-regulation strategies serving as mediators. In a randomized-controlled trial at a German University Medical Center, 112 prostatectomy-patients with partners were randomly assigned to a dyadic PFE-planning condition or one of three active control conditions. Questionnaire data were assessed at multiple time points within six months post-surgery, measuring self-reported dyadic PFE-planning and pelvic-floor exercise as primary outcomes and social exchange (support, control) and a self-regulation strategy (action control) as mediating mechanisms. There were no specific intervention effects with regard to dyadic PFE-planning or pelvic-floor exercise, as two active control groups also showed increases in either of these variables. However, results suggested that patients instructed to plan dyadically still benefited from self-reported dyadic PFE-planning regarding pelvic-floor exercise. Cross-sectionally, received negative control from partners was negatively related with PFE only in control groups and individual action control mediated between self-reported dyadic PFE-planning and PFE for participants instructed to plan PFE dyadically. Longitudinally, action control mediated between self-reported dyadic PFE-planning and pelvic-floor exercise for all groups. Findings provide support for further investigation of dyadic planning in health-behavior change with short-term mediating effects of behavior-specific social exchange and long-term mediating effects of better self-regulation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Status and trends monitoring of the mainstem Columbia River: sample frame development and review of programs relevant to the development of an integrated approach to monitoring

    USGS Publications Warehouse

    Counihan, Timothy D.; Hardiman, Jill M.; Waste, Stephen

    2013-01-01

    Implementing an Integrated Status and Trends Monitoring program (ISTM) for the mainstem Columbia River will help identify trends in important natural resources and help us understand the long-term collective effects of management actions. In this report, we present progress towards the completion of a stepwise process that will facilitate the development of an ISTM for the mainstem Columbia River. We discuss planning and regulatory documents that can be used to identify monitoring goals and objectives and present existing monitoring and research activities that should be considered as the development of a Columbia River ISTM proceeds. We also report progress towards the development of sample frames for the Columbia and Snake Rivers and their floodplains. The sample frames were formulated using Digital Elevation Models (DEM’s) of the river channel and upland areas and a Generalized Random-Tessellation Stratified (GRTS) algorithm for an area based resource to generate “master sample(s).” Working with the Pacific Northwest Aquatic Monitoring Partnership (PNAMP) we facilitated the transfer of the sample frames to the PNAMP “Monitoring Sample Designer” tool. We then discuss aspects of response and survey designs as they pertain to the formulation of a mainstem Columbia River ISTM. As efforts to formulate an ISTM for the mainstem Columbia River proceed, practitioners should utilize the extensive literature describing the planning and implementation of fish and wildlife mitigation and recovery efforts in the Columbia River Basin. While we make progress towards establishing an ISTM framework, considerable work needs to be done to formulate an ISTM program for the mainstem Columbia River. Long-term monitoring programs have been established for other large rivers systems; scientists that have experience planning, implementing, and maintaining large river monitoring efforts such as those in the Colorado, Illinois, and Mississippi Rivers should be consulted and involved as efforts proceed.

  1. Treatment of chronic antibody mediated rejection with intravenous immunoglobulins and rituximab: A multicenter, prospective, randomized, double-blind clinical trial.

    PubMed

    Moreso, Francesc; Crespo, Marta; Ruiz, Juan C; Torres, Armando; Gutierrez-Dalmau, Alex; Osuna, Antonio; Perelló, Manel; Pascual, Julio; Torres, Irina B; Redondo-Pachón, Dolores; Rodrigo, Emilio; Lopez-Hoyos, Marcos; Seron, Daniel

    2018-04-01

    There are no approved treatments for chronic antibody mediated rejection (ABMR). We conducted a multicenter, prospective, randomized, placebo-controlled, double-blind clinical trial to evaluate efficacy and safety of intravenous immunoglobulins (IVIG) combined with rituximab (RTX) (EudraCT 2010-023746-67). Patients with transplant glomerulopathy and anti-HLA donor-specific antibodies (DSA) were eligible. Patients with estimated glomerular filtration rate (eGFR) <20 mL/min per 1.73m 2 and/or severe interstitial fibrosis/tubular atrophy were excluded. Patients were randomized to receive IVIG (4 doses of 0.5 g/kg) and RTX (375 mg/m 2 ) or a wrapped isovolumetric saline infusion. Primary efficacy variable was the decline of eGFR at one year. Secondary efficacy variables included evolution of proteinuria, renal lesions, and DSA at 1 year. The planned sample size was 25 patients per group. During 2012-2015, 25 patients were randomized (13 to the treatment and 12 to the placebo group). The planned patient enrollment was not achieved because of budgetary constraints and slow patient recruitment. There were no differences between the treatment and placebo groups in eGFR decline (-4.2 ± 14.4 vs. -6.6 ± 12.0 mL/min per 1.73 m 2 , P-value = .475), increase of proteinuria (+0.9 ± 2.1 vs. +0.9 ± 2.1 g/day, P-value = .378), Banff scores at one year and MFI of the immunodominant DSA. Safety was similar between groups. These data suggest that the combination of IVIG and RTX is not useful in patients displaying transplant glomerulopathy and DSA. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  2. The use of group sequential, information-based sample size re-estimation in the design of the PRIMO study of chronic kidney disease.

    PubMed

    Pritchett, Yili; Jemiai, Yannis; Chang, Yuchiao; Bhan, Ishir; Agarwal, Rajiv; Zoccali, Carmine; Wanner, Christoph; Lloyd-Jones, Donald; Cannata-Andía, Jorge B; Thompson, Taylor; Appelbaum, Evan; Audhya, Paul; Andress, Dennis; Zhang, Wuyan; Solomon, Scott; Manning, Warren J; Thadhani, Ravi

    2011-04-01

    Chronic kidney disease is associated with a marked increase in risk for left ventricular hypertrophy and cardiovascular mortality compared with the general population. Therapy with vitamin D receptor activators has been linked with reduced mortality in chronic kidney disease and an improvement in left ventricular hypertrophy in animal studies. PRIMO (Paricalcitol capsules benefits in Renal failure Induced cardia MOrbidity) is a multinational, multicenter randomized controlled trial to assess the effects of paricalcitol (a selective vitamin D receptor activator) on mild to moderate left ventricular hypertrophy in patients with chronic kidney disease. Subjects with mild-moderate chronic kidney disease are randomized to paricalcitol or placebo after confirming left ventricular hypertrophy using a cardiac echocardiogram. Cardiac magnetic resonance imaging is then used to assess left ventricular mass index at baseline, 24 and 48 weeks, which is the primary efficacy endpoint of the study. Because of limited prior data to estimate sample size, a maximum information group sequential design with sample size re-estimation is implemented to allow sample size adjustment based on the nuisance parameter estimated using the interim data. An interim efficacy analysis is planned at a pre-specified time point conditioned on the status of enrollment. The decision to increase sample size depends on the observed treatment effect. A repeated measures analysis model, using available data at Week 24 and 48 with a backup model of an ANCOVA analyzing change from baseline to the final nonmissing observation, are pre-specified to evaluate the treatment effect. Gamma-family of spending function is employed to control family-wise Type I error rate as stopping for success is planned in the interim efficacy analysis. If enrollment is slower than anticipated, the smaller sample size used in the interim efficacy analysis and the greater percent of missing week 48 data might decrease the parameter estimation accuracy, either for the nuisance parameter or for the treatment effect, which might in turn affect the interim decision-making. The application of combining a group sequential design with a sample-size re-estimation in clinical trial design has the potential to improve efficiency and to increase the probability of trial success while ensuring integrity of the study.

  3. Urban land-use study plan for the National Water-Quality Assessment Program

    USGS Publications Warehouse

    Squillace, P.J.; Price, C.V.

    1996-01-01

    This study plan is for Urban Land-Use Studies initiated as part of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program. There are two Urban Land-Use Study objectives: (1) Define the water quality in recharge areas of shallow aquifers underlying areas of new residential and commercial land use in large metropolitan areas, and (2) determine which natural and human factors most strongly affect the occurrence of contaminants in these shallow aquifers. To meet objective 1, each NAWQA Study Unit will install and collect water samples from at least 30 randomly located monitoring wells in a metropolitan area. To meet objective 2, aquifer characteristics and land-use information will be documented. This includes particle-size analysis of each major lithologic unit both in the unsaturated zone and in the aquifer near the water table. The percentage of organic carbon also will be determined for each lithologic unit. Geographic information system coverages will be created that document existing land use around the wells. These data will aid NAWQA personnel in relating natural and human factors to the occurrence of contaminants. Water samples for age dating also will be collected from all monitoring wells, but the samples will be stored until the occurrence of contaminants has been determined. Age-date analysis will be done only on those samples that have no detectable concentrations of anthropogenic contaminants.

  4. Comparison of the perspectives of managers, employees and clients regarding the individual barriers of family planning counseling in healthcare centers of isfahan in 2012.

    PubMed

    Taheri, Safoura; Ehsanpour, Soheila; Kohan, Shahnaze; Farzi, Saba; Jaafarpour, Molouk; Direkvand-Moghaddam, Ashraf

    2014-03-01

    Family planning is a lifestyle that is selected voluntarily and is based on the knowledge, attitude and responsible decision making by couples in order to promote the health and welfare of the family and the advancement of the society. In this regard, family planning counseling plays an important role in making informed decisions if used properly and in a responsible way. Detection of individual barriers in family planning counseling based on the viewpoints of managers, employees and clients who are key participants in the healthcare service provision is a major step towards appropriate planning to modify or eliminate such barriers. The present study was conducted with the goal of comparing managers', employees' and clients' viewpoints about individual barriers in family planning counseling in health care centers in Isfahan in 2012. This was a cross-sectional one-step three-group comparative descriptive study conducted on 295 subjects including 59 managers, 110 employees and 126 clients in medical health care centers in Isfahan in 2012. The managers and employees were selected by census sampling, and the clients were recruited through convenient random sampling. The data collection tool was a researcher-designed questionnaire, which was designed in two sections of fertility and personal characteristics, and viewpoint measurement. Descriptive and inferential statistical tests were used to analyze the data. The obtained results showed significant differences between mean scores of viewpoints in three groups of managers, employees and clients concerning individual barriers in family planning counseling. In addition, most of the managers, employees and clients reported individual barriers as an intermediate level barrier in the process of family planning counseling. Results indicate that subjects in three studied groups hold different views regarding the individual barriers in family planning counseling. This difference in the perspectives may be a factor that affects the quality of the provided services. Therefore, it is necessary for the healthcare providers to consider the main concerns of their clients regarding family planning.

  5. Enhancing local health department disaster response capacity with rapid community needs assessments: validation of a computerized program for binary attribute cluster sampling.

    PubMed

    Groenewold, Matthew R

    2006-01-01

    Local health departments are among the first agencies to respond to disasters or other mass emergencies. However, they often lack the ability to handle large-scale events. Plans including locally developed and deployed tools may enhance local response. Simplified cluster sampling methods can be useful in assessing community needs after a sudden-onset, short duration event. Using an adaptation of the methodology used by the World Health Organization Expanded Programme on Immunization (EPI), a Microsoft Access-based application for two-stage cluster sampling of residential addresses in Louisville/Jefferson County Metro, Kentucky was developed. The sampling frame was derived from geographically referenced data on residential addresses and political districts available through the Louisville/Jefferson County Information Consortium (LOJIC). The program randomly selected 30 clusters, defined as election precincts, from within the area of interest, and then, randomly selected 10 residential addresses from each cluster. The program, called the Rapid Assessment Tools Package (RATP), was tested in terms of accuracy and precision using data on a dichotomous characteristic of residential addresses available from the local tax assessor database. A series of 30 samples were produced and analyzed with respect to their precision and accuracy in estimating the prevalence of the study attribute. Point estimates with 95% confidence intervals were calculated by determining the proportion of the study attribute values in each of the samples and compared with the population proportion. To estimate the design effect, corresponding simple random samples of 300 addresses were taken after each of the 30 cluster samples. The sample proportion fell within +/-10 absolute percentage points of the true proportion in 80% of the samples. In 93.3% of the samples, the point estimate fell within +/-12.5%, and 96.7% fell within +/-15%. All of the point estimates fell within +/-20% of the true proportion. Estimates of the design effect ranged from 0.926 to 1.436 (mean = 1.157, median = 1.170) for the 30 samples. Although prospective evaluation of its performance in field trials or a real emergency is required to confirm its utility, this study suggests that the RATP, a locally designed and deployed tool, may provide population-based estimates of community needs or the extent of event-related consequences that are precise enough to serve as the basis for the initial post-event decisions regarding relief efforts.

  6. Spatial distributions of the red palm mite, Raoiella indica (Acari: Tenuipalpidae) on coconut and their implications for development of efficient sampling plans.

    PubMed

    Roda, A; Nachman, G; Hosein, F; Rodrigues, J C V; Peña, J E

    2012-08-01

    The red palm mite (Raoiella indica), an invasive pest of coconut, entered the Western hemisphere in 2004, then rapidly spread through the Caribbean and into Florida, USA. Developing effective sampling methods may aid in the timely detection of the pest in a new area. Studies were conducted to provide and compare intra tree spatial distribution of red palm mite populations on coconut in two different geographical areas, Trinidad and Puerto Rico, recently invaded by the mite. The middle stratum of a palm hosted significantly more mites than fronds from the upper or lower canopy and fronds from the lower stratum, on average, had significantly fewer mites than the two other strata. The mite populations did not vary within a frond. Mite densities on the top section of the pinna had significantly lower mite densities than the two other sections, which were not significantly different from each other. In order to improve future sampling plans for the red palm mite, the data was used to estimate the variance components associated with the various levels of the hierarchical sampling design. Additionally, presence-absence data were used to investigate the probability of no mites being present in a pinna section randomly chosen from a frond inhabited by mites at a certain density. Our results show that the most precise density estimate at the plantation level is to sample one pinna section per tree from as many trees as possible.

  7. A random walk rule for phase I clinical trials.

    PubMed

    Durham, S D; Flournoy, N; Rosenberger, W F

    1997-06-01

    We describe a family of random walk rules for the sequential allocation of dose levels to patients in a dose-response study, or phase I clinical trial. Patients are sequentially assigned the next higher, same, or next lower dose level according to some probability distribution, which may be determined by ethical considerations as well as the patient's response. It is shown that one can choose these probabilities in order to center dose level assignments unimodally around any target quantile of interest. Estimation of the quantile is discussed; the maximum likelihood estimator and its variance are derived under a two-parameter logistic distribution, and the maximum likelihood estimator is compared with other nonparametric estimators. Random walk rules have clear advantages: they are simple to implement, and finite and asymptotic distribution theory is completely worked out. For a specific random walk rule, we compute finite and asymptotic properties and give examples of its use in planning studies. Having the finite distribution theory available and tractable obviates the need for elaborate simulation studies to analyze the properties of the design. The small sample properties of our rule, as determined by exact theory, compare favorably to those of the continual reassessment method, determined by simulation.

  8. Real-time dynamic modelling for the design of a cluster-randomized phase 3 Ebola vaccine trial in Sierra Leone.

    PubMed

    Camacho, A; Eggo, R M; Goeyvaerts, N; Vandebosch, A; Mogg, R; Funk, S; Kucharski, A J; Watson, C H; Vangeneugden, T; Edmunds, W J

    2017-01-23

    Declining incidence and spatial heterogeneity complicated the design of phase 3 Ebola vaccine trials during the tail of the 2013-16 Ebola virus disease (EVD) epidemic in West Africa. Mathematical models can provide forecasts of expected incidence through time and can account for both vaccine efficacy in participants and effectiveness in populations. Determining expected disease incidence was critical to calculating power and determining trial sample size. In real-time, we fitted, forecasted, and simulated a proposed phase 3 cluster-randomized vaccine trial for a prime-boost EVD vaccine in three candidate regions in Sierra Leone. The aim was to forecast trial feasibility in these areas through time and guide study design planning. EVD incidence was highly variable during the epidemic, especially in the declining phase. Delays in trial start date were expected to greatly reduce the ability to discern an effect, particularly as a trial with an effective vaccine would cause the epidemic to go extinct more quickly in the vaccine arm. Real-time updates of the model allowed decision-makers to determine how trial feasibility changed with time. This analysis was useful for vaccine trial planning because we simulated effectiveness as well as efficacy, which is possible with a dynamic transmission model. It contributed to decisions on choice of trial location and feasibility of the trial. Transmission models should be utilised as early as possible in the design process to provide mechanistic estimates of expected incidence, with which decisions about sample size, location, timing, and feasibility can be determined. Copyright © 2016. Published by Elsevier Ltd.

  9. Scaling Academic Planning in Community College: A Randomized Controlled Trial. REL 2017-204

    ERIC Educational Resources Information Center

    Visher, Mary G.; Mayer, Alexander K.; Johns, Michael; Rudd, Timothy; Levine, Andrew; Rauner, Mary

    2016-01-01

    Community college students often lack an academic plan to guide their choices of coursework to achieve their educational goals, in part because counseling departments typically lack the capacity to advise students at scale. This randomized controlled trial tests the impact of guaranteed access to one of two alternative counseling sessions (group…

  10. Alternative sample sizes for verification dose experiments and dose audits

    NASA Astrophysics Data System (ADS)

    Taylor, W. A.; Hansen, J. M.

    1999-01-01

    ISO 11137 (1995), "Sterilization of Health Care Products—Requirements for Validation and Routine Control—Radiation Sterilization", provides sampling plans for performing initial verification dose experiments and quarterly dose audits. Alternative sampling plans are presented which provide equivalent protection. These sampling plans can significantly reduce the cost of testing. These alternative sampling plans have been included in a draft ISO Technical Report (type 2). This paper examines the rational behind the proposed alternative sampling plans. The protection provided by the current verification and audit sampling plans is first examined. Then methods for identifying equivalent plans are highlighted. Finally, methods for comparing the cost associated with the different plans are provided. This paper includes additional guidance for selecting between the original and alternative sampling plans not included in the technical report.

  11. Intracranial stereotactic radiosurgery with an adapted linear accelerator vs. robotic radiosurgery: Comparison of dosimetric treatment plan quality.

    PubMed

    Treuer, Harald; Hoevels, Moritz; Luyken, Klaus; Visser-Vandewalle, Veerle; Wirths, Jochen; Kocher, Martin; Ruge, Maximilian

    2015-06-01

    Stereotactic radiosurgery with an adapted linear accelerator (linac-SRS) is an established therapy option for brain metastases, benign brain tumors, and arteriovenous malformations. We intended to investigate whether the dosimetric quality of treatment plans achieved with a CyberKnife (CK) is at least equivalent to that for linac-SRS with circular or micromultileaf collimators (microMLC). A random sample of 16 patients with 23 target volumes, previously treated with linac-SRS, was replanned with CK. Planning constraints were identical dose prescription and clinical applicability. In all cases uniform optimization scripts and inverse planning objectives were used. Plans were compared with respect to coverage, minimal dose within target volume, conformity index, and volume of brain tissue irradiated with ≥ 10 Gy. Generating the CK plan was unproblematic with simple optimization scripts in all cases. With the CK plans, coverage, minimal target volume dosage, and conformity index were significantly better, while no significant improvement could be shown regarding the 10 Gy volume. Multiobjective comparison for the irradiated target volumes was superior in the CK plan in 20 out of 23 cases and equivalent in 3 out of 23 cases. Multiobjective comparison for the treated patients was superior in the CK plan in all 16 cases. The results clearly demonstrate the superiority of the irradiation plan for CK compared to classical linac-SRS with circular collimators and microMLC. In particular, the average minimal target volume dose per patient, increased by 1.9 Gy, and at the same time a 14% better conformation index seems to be an improvement with clinical relevance.

  12. Comparison of chain sampling plans with single and double sampling plans

    NASA Technical Reports Server (NTRS)

    Stephens, K. S.; Dodge, H. F.

    1976-01-01

    The efficiency of chain sampling is examined through matching of operating characteristics (OC) curves of chain sampling plans (ChSP) with single and double sampling plans. In particular, the operating characteristics of some ChSP-0, 3 and 1, 3 as well as ChSP-0, 4 and 1, 4 are presented, where the number pairs represent the first and the second cumulative acceptance numbers. The fact that the ChSP procedure uses cumulative results from two or more samples and that the parameters can be varied to produce a wide variety of operating characteristics raises the question whether it may be possible for such plans to provide a given protection with less inspection than with single or double sampling plans. The operating ratio values reported illustrate the possibilities of matching single and double sampling plans with ChSP. It is shown that chain sampling plans provide improved efficiency over single and double sampling plans having substantially the same operating characteristics.

  13. Individual care plans for chronically ill patients within primary care in the Netherlands: Dissemination and associations with patient characteristics and patient-perceived quality of care.

    PubMed

    Jansen, Daphne L; Heijmans, Monique; Rijken, Mieke

    2015-06-01

    To examine the use of individual care plans (ICPs) within primary chronic illness care in the Netherlands, and to explore the relationships between ICP use, patient characteristics, and patient-perceived quality of care. Cross-sectional study using survey data from a panel of chronically ill patients and medical registration data provided by their general practices. A sample of 1377 patients with somatic chronic disease(s) randomly selected in general practices throughout the Netherlands, supplemented with a sample of 225 COPD patients, also recruited from general practices. (i) Percentage of ICP use based on self-report by chronically ill patients, and (ii) patient-perceived quality of care as assessed using the Patient Assessment of Chronic Illness Care (PACIC). ICP use among the total generic sample was low (9%), but slightly higher (13%) among patients diagnosed with diabetes or COPD, diseases for which disease management programmes have been set up in the Netherlands. Patients with a low educational level and patients with poor(er) self-rated health were more likely to have an ICP. Compared with patients without an ICP, patients with an ICP more often reported that the care they received was patient-centred, proactive, planned, and included collaborative goal setting, problem-solving, and follow-up support. Findings reveal a discrepancy between practice and policy aspirations regarding ICP use in primary chronic illness care. More research is needed to gain insight into the effectiveness of ICPs to improve the quality of chronic illness care in various patient populations.

  14. SU-F-T-192: Study of Robustness Analysis Method of Multiple Field Optimized IMPT Plans for Head & Neck Patients

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

    Li, Y; Wang, X; Li, H

    Purpose: Proton therapy is more sensitive to uncertainties than photon treatments due to protons’ finite range depending on the tissue density. Worst case scenario (WCS) method originally proposed by Lomax has been adopted in our institute for robustness analysis of IMPT plans. This work demonstrates that WCS method is sufficient enough to take into account of the uncertainties which could be encountered during daily clinical treatment. Methods: A fast and approximate dose calculation method is developed to calculate the dose for the IMPT plan under different setup and range uncertainties. Effects of two factors, inversed square factor and range uncertainty,more » are explored. WCS robustness analysis method was evaluated using this fast dose calculation method. The worst-case dose distribution was generated by shifting isocenter by 3 mm along x,y and z directions and modifying stopping power ratios by ±3.5%. 1000 randomly perturbed cases in proton range and x, yz directions were created and the corresponding dose distributions were calculated using this approximated method. DVH and dosimetric indexes of all 1000 perturbed cases were calculated and compared with the result using worst case scenario method. Results: The distributions of dosimetric indexes of 1000 perturbed cases were generated and compared with the results using worst case scenario. For D95 of CTVs, at least 97% of 1000 perturbed cases show higher values than the one of worst case scenario. For D5 of CTVs, at least 98% of perturbed cases have lower values than worst case scenario. Conclusion: By extensively calculating the dose distributions under random uncertainties, WCS method was verified to be reliable in evaluating the robustness level of MFO IMPT plans of H&N patients. The extensively sampling approach using fast approximated method could be used in evaluating the effects of different factors on the robustness level of IMPT plans in the future.« less

  15. Sampling-based real-time motion planning under state uncertainty for autonomous micro-aerial vehicles in GPS-denied environments.

    PubMed

    Li, Dachuan; Li, Qing; Cheng, Nong; Song, Jingyan

    2014-11-18

    This paper presents a real-time motion planning approach for autonomous vehicles with complex dynamics and state uncertainty. The approach is motivated by the motion planning problem for autonomous vehicles navigating in GPS-denied dynamic environments, which involves non-linear and/or non-holonomic vehicle dynamics, incomplete state estimates, and constraints imposed by uncertain and cluttered environments. To address the above motion planning problem, we propose an extension of the closed-loop rapid belief trees, the closed-loop random belief trees (CL-RBT), which incorporates predictions of the position estimation uncertainty, using a factored form of the covariance provided by the Kalman filter-based estimator. The proposed motion planner operates by incrementally constructing a tree of dynamically feasible trajectories using the closed-loop prediction, while selecting candidate paths with low uncertainty using efficient covariance update and propagation. The algorithm can operate in real-time, continuously providing the controller with feasible paths for execution, enabling the vehicle to account for dynamic and uncertain environments. Simulation results demonstrate that the proposed approach can generate feasible trajectories that reduce the state estimation uncertainty, while handling complex vehicle dynamics and environment constraints.

  16. What is the best?: simple versus visitor restricted rest period.

    PubMed

    Silvius-Byron, Stephanie A; Florimonte, Christine; Panganiban, Elizabeth G; Ulmer, Janice Fitzgerald

    2014-05-01

    The aim of this study was to compare a highly structured planned rest protocol that includes visitor and healthcare personnel restrictions with a simple planned rest period that encourages patients to rest during a designated time without restriction of visitors and healthcare personnel. Many hospitals acute care have begun to restrict visitors and nonessential health team interventions during specific times despite the lack of experimentally designed studies. Using a convenience sample of 52 intermediate care unit patients, a randomized experimental design study compared a highly structured planned rest protocol with restriction of visitors/healthcare personnel to a simple planned rest period without restrictions. The primary outcome variable was the patient's perceived quality of rest after a 2-hour rest period. Intermediate care patients' perception of rest and sleep during a designated rest period was similar whether elaborate rest strategies were used, including visitor and healthcare personnel restrictions, or if it was only suggested they rest and the door to their room closed. The restriction of visitors and healthcare personnel during a 2-hour rest period did not improve the patient's perception of rest or how long it took them to go to sleep.

  17. Sampling-Based Real-Time Motion Planning under State Uncertainty for Autonomous Micro-Aerial Vehicles in GPS-Denied Environments

    PubMed Central

    Li, Dachuan; Li, Qing; Cheng, Nong; Song, Jingyan

    2014-01-01

    This paper presents a real-time motion planning approach for autonomous vehicles with complex dynamics and state uncertainty. The approach is motivated by the motion planning problem for autonomous vehicles navigating in GPS-denied dynamic environments, which involves non-linear and/or non-holonomic vehicle dynamics, incomplete state estimates, and constraints imposed by uncertain and cluttered environments. To address the above motion planning problem, we propose an extension of the closed-loop rapid belief trees, the closed-loop random belief trees (CL-RBT), which incorporates predictions of the position estimation uncertainty, using a factored form of the covariance provided by the Kalman filter-based estimator. The proposed motion planner operates by incrementally constructing a tree of dynamically feasible trajectories using the closed-loop prediction, while selecting candidate paths with low uncertainty using efficient covariance update and propagation. The algorithm can operate in real-time, continuously providing the controller with feasible paths for execution, enabling the vehicle to account for dynamic and uncertain environments. Simulation results demonstrate that the proposed approach can generate feasible trajectories that reduce the state estimation uncertainty, while handling complex vehicle dynamics and environment constraints. PMID:25412217

  18. 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…

  19. Modeling efficiency at the process level: an examination of the care planning process in nursing homes.

    PubMed

    Lee, Robert H; Bott, Marjorie J; Gajewski, Byron; Taunton, Roma Lee

    2009-02-01

    To examine the efficiency of the care planning process in nursing homes. We collected detailed primary data about the care planning process for a stratified random sample of 107 nursing homes from Kansas and Missouri. We used these data to calculate the average direct cost per care plan and used data on selected deficiencies from the Online Survey Certification and Reporting System to measure the quality of care planning. We then analyzed the efficiency of the assessment process using corrected ordinary least squares (COLS) and data envelopment analysis (DEA). Both approaches suggested that there was considerable inefficiency in the care planning process. The average COLS score was 0.43; the average DEA score was 0.48. The correlation between the two sets of scores was quite high, and there was no indication that lower costs resulted in lower quality. For-profit facilities were significantly more efficient than not-for-profit facilities. Multiple studies of nursing homes have found evidence of inefficiency, but virtually all have had measurement problems that raise questions about the results. This analysis, which focuses on a process with much simpler measurement issues, finds evidence of inefficiency that is largely consistent with earlier studies. Making nursing homes more efficient merits closer attention as a strategy for improving care. Increasing efficiency by adopting well-designed, reliable processes can simultaneously reduce costs and improve quality.

  20. Using occupancy models of forest breeding birds to prioritize conservation planning

    USGS Publications Warehouse

    De Wan, A. A.; Sullivan, P.J.; Lembo, A.J.; Smith, C.R.; Maerz, J.C.; Lassoie, J.P.; Richmond, M.E.

    2009-01-01

    As urban development continues to encroach on the natural and rural landscape, land-use planners struggle to identify high priority conservation areas for protection. Although knowing where urban-sensitive species may be occurring on the landscape would facilitate conservation planning, research efforts are often not sufficiently designed to make quality predictions at unknown locations. Recent advances in occupancy modeling allow for more precise estimates of occupancy by accounting for differences in detectability. We applied these techniques to produce robust estimates of habitat occupancy for a subset of forest breeding birds, a group that has been shown to be sensitive to urbanization, in a rapidly urbanizing yet biological diverse region of New York State. We found that detection probability ranged widely across species, from 0.05 to 0.8. Our models suggest that detection probability declined with increasing forest fragmentation. We also found that the probability of occupancy of forest breeding birds is negatively influenced by increasing perimeter-area ratio of forest fragments and urbanization in the surrounding habitat matrix. We capitalized on our random sampling design to produce spatially explicit models that predict high priority conservation areas across the entire region, where interior-species were most likely to occur. Finally, we use our predictive maps to demonstrate how a strict sampling design coupled with occupancy modeling can be a valuable tool for prioritizing biodiversity conservation in land-use planning. ?? 2009 Elsevier Ltd.

  1. Gaps, conflicts, and consensus in the ethics statements of professional associations, medical groups, and health plans

    PubMed Central

    Berkman, N; Wynia, M; Churchill, L

    2004-01-01

    Background: Patients today interact with physicians, physician groups, and health plans, each of which may follow distinct ethical guidelines. Method: We systematically compared physician codes of ethics with ethics policies at physician group practices and health plans, using the 1998–99 policies of 38 organisations—18 medical associations (associations), nine physician group practices (groups), and 12 health plans (plans)—selected using random and stratified purposive sampling. A clinician and a social scientist independently abstracted each document, using a 397-item health care ethics taxonomy; a reconciled abstraction form was used for analysis. This study focuses on ethics policies regarding professional obligation towards patients, resource allocation, and care for the vulnerable in society. Results: A majority in all three groups mention "fiduciary obligations" of one sort or another, but associations generally address physician/patient relations but not health plan obligations, while plans rarely endorse physicians' obligations of advocacy, beneficence, and non-maleficence. Except for occasional mentions of cost effectiveness or efficiency, ethical considerations in resource allocation rarely arise in the ethics policies of all three organisational types. Very few associations, groups, or plans specifically endorse obligations to vulnerable populations. Conclusions: With some important exceptions, we found that the ethics policies of associations, groups, and plans are narrowly focused and often ignore important ethical concerns for society, such as resource allocation and care for vulnerable populations. More collaborative work is needed to build integrated sets of ethical standards that address the aims and responsibilities of the major stakeholders in health care delivery. PMID:15289536

  2. Nonuniform sampling theorems for random signals in the linear canonical transform domain

    NASA Astrophysics Data System (ADS)

    Shuiqing, Xu; Congmei, Jiang; Yi, Chai; Youqiang, Hu; Lei, Huang

    2018-06-01

    Nonuniform sampling can be encountered in various practical processes because of random events or poor timebase. The analysis and applications of the nonuniform sampling for deterministic signals related to the linear canonical transform (LCT) have been well considered and researched, but up to now no papers have been published regarding the various nonuniform sampling theorems for random signals related to the LCT. The aim of this article is to explore the nonuniform sampling and reconstruction of random signals associated with the LCT. First, some special nonuniform sampling models are briefly introduced. Second, based on these models, some reconstruction theorems for random signals from various nonuniform samples associated with the LCT have been derived. Finally, the simulation results are made to prove the accuracy of the sampling theorems. In addition, the latent real practices of the nonuniform sampling for random signals have been also discussed.

  3. User-driven health care: answering multidimensional information needs in individual patients utilizing post-EBM approaches: an operational model.

    PubMed

    Biswas, Rakesh; Maniam, Jayanthy; Lee, Edwin Wen Huo; Gopal, Premalatha; Umakanth, Shashikiran; Dahiya, Sumit; Ahmed, Sayeed

    2008-10-01

    The hypothesis in the conceptual model was that a user-driven innovation in presently available information and communication technology infrastructure would be able to meet patient and health professional users information needs and help them attain better health outcomes. An operational model was created to plan a trial on a sample diabetic population utilizing a randomized control trial design, assigning one randomly selected group of diabetics to receive electronic information intervention and analyse if it would improve their health outcomes in comparison with a matched diabetic population who would only receive regular medical intervention. Diabetes was chosen for this particular trial, as it is a major chronic illness in Malaysia as elsewhere in the world. It is in essence a position paper for how the study concept should be organized to stimulate wider discussion prior to beginning the study.

  4. Associations Among Religiousness and Community Volunteerism in National Random Samples of American Adults.

    PubMed

    Haggard, Megan C; Kang, Linda L; Rowatt, Wade C; Shen, Megan Johnson

    2015-01-01

    The connection between religiousness and volunteering for the community can be explained through two distinct features of religion. First, religious organizations are social groups that encourage members to help others through planned opportunities. Second, helping others is regarded as an important value for members in religious organizations to uphold. We examined the relationship between religiousness and self-reported community volunteering in two independent national random surveys of American adults (i.e., the 2005 and 2007 waves of the Baylor Religion Survey). In both waves, frequency of religious service attendance was associated with an increase in likelihood that individuals would volunteer, whether through their religious organization or not, whereas frequency of reading sacred texts outside of religious services was associated with an increase in likelihood of volunteering only for or through their religious organization. The role of religion in community volunteering is discussed in light of these findings.

  5. Cost, cost-efficiency and cost-effectiveness of integrated family planning and HIV services.

    PubMed

    Shade, Starley B; Kevany, Sebastian; Onono, Maricianah; Ochieng, George; Steinfeld, Rachel L; Grossman, Daniel; Newmann, Sara J; Blat, Cinthia; Bukusi, Elizabeth A; Cohen, Craig R

    2013-10-01

    To evaluate costs, cost-efficiency and cost-effectiveness of integration of family planning into HIV services. Integration of family planning services into HIV care and treatment clinics. A cluster-randomized trial. Twelve health facilities in Nyanza, Kenya were randomized to integrate family planning into HIV care and treatment; six health facilities were randomized to (nonintegrated) standard-of-care with separately delivered family planning and HIV services. We assessed costs, cost-efficiency (cost per additional use of more effective family planning), and cost-effectiveness (cost per pregnancy averted) associated with the first year of integration of family planning into HIV care. More effective family planning methods included oral and injectable contraceptives, subdermal implants, intrauterine device, and female and male sterilization. We collected cost data through interviews with study staff and review of financial records to determine costs of service integration. Integration of services was associated with an average marginal cost of $841 per site and $48 per female patient. Average overall and marginal costs of integration were associated with personnel costs [initial ($1003 vs. $872) and refresher ($498 vs. $330) training, mentoring ($1175 vs. $902) and supervision ($1694 vs. $1636)], with fewer resources required for other fixed ($18 vs. $0) and recurring expenses ($471 vs. $287). Integration was associated with a marginal cost of $65 for each additional use of more effective family planning and $1368 for each pregnancy averted. Integration of family planning and HIV services is feasible, inexpensive to implement, and cost-efficient in the Kenyan setting, and thus supports current Kenyan integration policy.

  6. A Study on Strategic Planning and Procurement of Medicals in Uganda’s Regional Referral Hospitals

    PubMed Central

    2016-01-01

    This study was an analysis of the effect of strategic planning on procurement of medicals in Uganda’s regional referral hospitals (RRH’s). Medicals were defined as essential medicines, medical devices and medical equipment. The Ministry of Health (MOH) has been carrying out strategic planning for the last 15 years via the Health Sector Strategic Plans. Their assumption was that strategic planning would translate to strategic procurement and consequently, availability of medicals in the RRH’s. However, despite the existence of these plans, there have been many complaints about expired drugs and shortages in RRH’s. For this purpose, a third variable was important because it served the role of mediation. A questionnaire was used to obtain information on perceptions of 206 respondents who were selected using simple random sampling. 8 key informant interviews were held, 2 in each RRH. 4 Focus Group Discussions were held, 1 for each RRH, and between 5 and 8 staff took part as discussants for approximately three hours. The findings suggested that strategic planning was affected by funding to approximately 34% while the relationship between funding and procurement was 35%. The direct relationship between strategic planning and procurement was 18%. However when the total causal effect was computed it turned out that strategic planning and the related variable of funding contributed 77% to procurement of medicals under the current hierarchical model where MOH is charged with development of strategic plans for the entire health sector. Since even with this contribution there were complaints, the study proposed a new model called CALF which according to a simulation, if adopted by MOH, strategic planning would contribute 87% to effectiveness in procurement of medicals. PMID:28299158

  7. A Study on Strategic Planning and Procurement of Medicals in Uganda's Regional Referral Hospitals.

    PubMed

    Masembe, Ishak Kamaradi

    2016-12-31

    This study was an analysis of the effect of strategic planning on procurement of medicals in Uganda's regional referral hospitals (RRH's). Medicals were defined as essential medicines, medical devices and medical equipment. The Ministry of Health (MOH) has been carrying out strategic planning for the last 15 years via the Health Sector Strategic Plans. Their assumption was that strategic planning would translate to strategic procurement and consequently, availability of medicals in the RRH's. However, despite the existence of these plans, there have been many complaints about expired drugs and shortages in RRH's. For this purpose, a third variable was important because it served the role of mediation. A questionnaire was used to obtain information on perceptions of 206 respondents who were selected using simple random sampling. 8 key informant interviews were held, 2 in each RRH. 4 Focus Group Discussions were held, 1 for each RRH, and between 5 and 8 staff took part as discussants for approximately three hours. The findings suggested that strategic planning was affected by funding to approximately 34% while the relationship between funding and procurement was 35%. The direct relationship between strategic planning and procurement was 18%. However when the total causal effect was computed it turned out that strategic planning and the related variable of funding contributed 77% to procurement of medicals under the current hierarchical model where MOH is charged with development of strategic plans for the entire health sector. Since even with this contribution there were complaints, the study proposed a new model called CALF which according to a simulation, if adopted by MOH, strategic planning would contribute 87% to effectiveness in procurement of medicals.

  8. Quantifying Unnecessary Normal Tissue Complication Risks due to Suboptimal Planning: A Secondary Study of RTOG 0126

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

    Moore, Kevin L., E-mail: kevinmoore@ucsd.edu; Schmidt, Rachel; Moiseenko, Vitali

    Purpose: The purpose of this study was to quantify the frequency and clinical severity of quality deficiencies in intensity modulated radiation therapy (IMRT) planning in the Radiation Therapy Oncology Group 0126 protocol. Methods and Materials: A total of 219 IMRT patients from the high-dose arm (79.2 Gy) of RTOG 0126 were analyzed. To quantify plan quality, we used established knowledge-based methods for patient-specific dose-volume histogram (DVH) prediction of organs at risk and a Lyman-Kutcher-Burman (LKB) model for grade ≥2 rectal complications to convert DVHs into normal tissue complication probabilities (NTCPs). The LKB model was validated by fitting dose-response parameters relative tomore » observed toxicities. The 90th percentile (22 of 219) of plans with the lowest excess risk (difference between clinical and model-predicted NTCP) were used to create a model for the presumed best practices in the protocol (pDVH{sub 0126,top10%}). Applying the resultant model to the entire sample enabled comparisons between DVHs that patients could have received to DVHs they actually received. Excess risk quantified the clinical impact of suboptimal planning. Accuracy of pDVH predictions was validated by replanning 30 of 219 patients (13.7%), including equal numbers of presumed “high-quality,” “low-quality,” and randomly sampled plans. NTCP-predicted toxicities were compared to adverse events on protocol. Results: Existing models showed that bladder-sparing variations were less prevalent than rectum quality variations and that increased rectal sparing was not correlated with target metrics (dose received by 98% and 2% of the PTV, respectively). Observed toxicities were consistent with current LKB parameters. Converting DVH and pDVH{sub 0126,top10%} to rectal NTCPs, we observed 94 of 219 patients (42.9%) with ≥5% excess risk, 20 of 219 patients (9.1%) with ≥10% excess risk, and 2 of 219 patients (0.9%) with ≥15% excess risk. Replanning demonstrated the predicted NTCP reductions while maintaining the volume of the PTV receiving prescription dose. An equivalent sample of high-quality plans showed fewer toxicities than low-quality plans, 6 of 73 versus 10 of 73 respectively, although these differences were not significant (P=.21) due to insufficient statistical power in this retrospective study. Conclusions: Plan quality deficiencies in RTOG 0126 exposed patients to substantial excess risk for rectal complications.« less

  9. SU-G-TeP3-14: Three-Dimensional Cluster Model in Inhomogeneous Dose Distribution

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

    Wei, J; Penagaricano, J; Narayanasamy, G

    2016-06-15

    Purpose: We aim to investigate 3D cluster formation in inhomogeneous dose distribution to search for new models predicting radiation tissue damage and further leading to new optimization paradigm for radiotherapy planning. Methods: The aggregation of higher dose in the organ at risk (OAR) than a preset threshold was chosen as the cluster whose connectivity dictates the cluster structure. Upon the selection of the dose threshold, the fractional density defined as the fraction of voxels in the organ eligible to be part of the cluster was determined according to the dose volume histogram (DVH). A Monte Carlo method was implemented tomore » establish a case pertinent to the corresponding DVH. Ones and zeros were randomly assigned to each OAR voxel with the sampling probability equal to the fractional density. Ten thousand samples were randomly generated to ensure a sufficient number of cluster sets. A recursive cluster searching algorithm was developed to analyze the cluster with various connectivity choices like 1-, 2-, and 3-connectivity. The mean size of the largest cluster (MSLC) from the Monte Carlo samples was taken to be a function of the fractional density. Various OARs from clinical plans were included in the study. Results: Intensive Monte Carlo study demonstrates the inverse relationship between the MSLC and the cluster connectivity as anticipated and the cluster size does not change with fractional density linearly regardless of the connectivity types. An initially-slow-increase to exponential growth transition of the MSLC from low to high density was observed. The cluster sizes were found to vary within a large range and are relatively independent of the OARs. Conclusion: The Monte Carlo study revealed that the cluster size could serve as a suitable index of the tissue damage (percolation cluster) and the clinical outcome of the same DVH might be potentially different.« less

  10. Evaluation of enrollee satisfaction with Iowa's Dental Wellness Plan for the Medicaid expansion population.

    PubMed

    Reynolds, Julie C; McKernan, Susan C; Sukalski, Jennifer M C; Damiano, Peter C

    2018-12-01

    Dental coverage for Iowa's Medicaid expansion population is provided through the Dental Wellness Plan (DWP), implemented in May 2014. The plan targets healthy behavior incentives via an earned benefits structure, whereby additional services are covered if enrollees return every 6-12 months for routine dental visits. This study examines enrollee satisfaction with the DWP. We surveyed a random sample of DWP enrollees 1 year after program implementation about their experiences. Survey items covered dental plan satisfaction, self-rated measures of health, and knowledge and attitudes toward the earned benefits approach. Dental plan satisfaction was rated as low by 38 percent of respondents (n = 416), moderate by 25 percent (n = 276), and high by 37 percent (n = 402). A majority of respondents (66 percent) did not know about the earned benefits structure. Regression analysis indicated that respondents most likely to have low plan satisfaction were those who felt it was difficult to earn benefits (OR 3.66, P < 0.001) and those who were unable to find (OR 3.17, P < 0.001), or did not try to find (OR 3.51, P < 0.001), a regular dentist in the plan. Satisfaction with a new model of dental insurance was influenced by whether enrollees had a regular source of care and their perceived ability to return for regular checkups in order to earn covered benefits. © 2017 American Association of Public Health Dentistry.

  11. Analysis of the habitat of Henslow's sparrows and Grasshopper sparrows compared to random grassland areas

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

    Maier, Kristen; Walton, Rod; Kasper, Peter

    2005-01-01

    Henslow's Sparrows are endangered prairie birds, and Grasshopper Sparrows are considered rare prairie birds. Both of these birds were abundant in Illinois, but their populations have been declining due to loss of the grasslands. This begins an ongoing study of the birds habitat so Fermilab can develop a land management plan for the Henslow's and Grasshoppers. The Henslow's were found at ten sites and Grasshoppers at eight sites. Once the birds were located, the vegetation at their sites was studied. Measurements of the maximum plant height, average plant height, and duff height were taken and estimates of the percent ofmore » grass, forbs, duff, and bare ground were recorded for each square meter studied. The same measurements were taken at ten random grassland sites on Fermilab property. Several t-tests were performed on the data, and it was found that both Henslow's Sparrows and Grasshopper Sparrows preferred areas with a larger percentage of grass than random areas. Henslow's also preferred areas with less bare ground than random areas, while Grasshoppers preferred areas with more bare ground than random areas. In addition, Grasshopper Sparrows preferred a lower percentage of forbs than was found in random areas and a shorter average plant height than the random locations. Two-sample variance tests suggested significantly less variance for both Henslow's Sparrows and Grasshopper Sparrows for maximum plant height in comparison to the random sites. For both birds, the test suggested a significant difference in the variance of the percentage of bare ground compared to random sites, but only the Grasshopper Sparrow showed significance in the variation in the percentage of forbs.« less

  12. Prevalence of dental anomalies in Saudi orthodontic patients.

    PubMed

    Al-Jabaa, Aljazi H; Aldrees, Abdullah M

    2013-07-01

    This study aimed to investigate the prevalence of dental anomalies and study the association of these anomalies with different types of malocclusion in a random sample of Saudi orthodontic patients. Six hundred and two randomly selected pretreatment records including orthopantomographs (OPG), and study models were evaluated. The molar relationship was determined using pretreatment study models, and OPG were examined to investigate the prevalence of dental anomalies among the sample. The most common types of the investigated anomalies were: impaction followed by hypodontia, microdontia, macrodontia, ectopic eruption and supernumerary. No statistical significant correlations were observed between sex and dental anomalies. Dental anomalies were more commonly found in class I followed by asymmetric molar relation, then class II and finally class III molar relation. No malocclusion group had a statistically significant relation with any individual dental anomaly. The prevalence of dental anomalies among Saudi orthodontic patients was higher than the general population. Although, orthodontic patients have been reported to have high rates of dental anomalies, orthodontists often fail to consider this. If not detected, dental anomalies can complicate dental and orthodontic treatment; therefore, their presence should be carefully investigated during orthodontic diagnosis and considered during treatment planning.

  13. 40 CFR 141.802 - Coliform sampling plan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Coliform sampling plan. 141.802... sampling plan. (a) Each air carrier under this subpart must develop a coliform sampling plan covering each... required actions, including repeat and follow-up sampling, corrective action, and notification of...

  14. 40 CFR 141.802 - Coliform sampling plan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Coliform sampling plan. 141.802... sampling plan. (a) Each air carrier under this subpart must develop a coliform sampling plan covering each... required actions, including repeat and follow-up sampling, corrective action, and notification of...

  15. Establishing Evidence-Based Indications for Proton Therapy: An Overview of Current Clinical Trials

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

    Mishra, Mark V., E-mail: mmishra@umm.edu; Aggarwal, Sameer; Bentzen, Soren M.

    Purpose: To review and assess ongoing proton beam therapy (PBT) clinical trials and to identify major gaps. Methods and Materials: Active PBT clinical trials were identified from (clinicaltrials.gov) and the World Health Organization International Clinical Trials Platform Registry. Data on clinical trial disease site, age group, projected patient enrollment, expected start and end dates, study type, and funding source were extracted. Results: A total of 122 active PBT clinical trials were identified, with target enrollment of >42,000 patients worldwide. Ninety-six trials (79%), with a median planned sample size of 68, were classified as interventional studies. Observational studies accounted for 21% ofmore » trials but 71% (n=29,852) of planned patient enrollment. The most common PBT clinical trials focus on gastrointestinal tract tumors (21%, n=26), tumors of the central nervous system (15%, n=18), and prostate cancer (12%, n=15). Five active studies (lung, esophagus, head and neck, prostate, breast) will randomize patients between protons and photons, and 3 will randomize patients between protons and carbon ion therapy. Conclusions: The PBT clinical trial portfolio is expanding rapidly. Although the majority of ongoing studies are interventional, the majority of patients will be accrued to observational studies. Future efforts should focus on strategies to encourage optimal patient enrollment and retention, with an emphasis on randomized, controlled trials, which will require support from third-party payers. Results of ongoing PBT studies should be evaluated in terms of comparative effectiveness, as well as incremental effectiveness and value offered by PBT in comparison with conventional radiation modalities.« less

  16. Reliability of Space-Shuttle Pressure Vessels with Random Batch Effects

    NASA Technical Reports Server (NTRS)

    Feiveson, Alan H.; Kulkarni, Pandurang M.

    2000-01-01

    In this article we revisit the problem of estimating the joint reliability against failure by stress rupture of a group of fiber-wrapped pressure vessels used on Space-Shuttle missions. The available test data were obtained from an experiment conducted at the U.S. Department of Energy Lawrence Livermore Laboratory (LLL) in which scaled-down vessels were subjected to life testing at four accelerated levels of pressure. We estimate the reliability assuming that both the Shuttle and LLL vessels were chosen at random in a two-stage process from an infinite population with spools of fiber as the primary sampling unit. Two main objectives of this work are: (1) to obtain practical estimates of reliability taking into account random spool effects and (2) to obtain a realistic assessment of estimation accuracy under the random model. Here, reliability is calculated in terms of a 'system' of 22 fiber-wrapped pressure vessels, taking into account typical pressures and exposure times experienced by Shuttle vessels. Comparisons are made with previous studies. The main conclusion of this study is that, although point estimates of reliability are still in the 'comfort zone,' it is advisable to plan for replacement of the pressure vessels well before the expected Lifetime of 100 missions per Shuttle Orbiter. Under a random-spool model, there is simply not enough information in the LLL data to provide reasonable assurance that such replacement would not be necessary.

  17. Eliciting consumer preferences for health plans.

    PubMed

    Booske, B C; Sainfort, F; Hundt, A S

    1999-10-01

    To examine (1) what people say is important to them in choosing a health plan; (2) the effect, if any, that giving health plan information has on what people say is important to them; and (3) the effect of preference elicitation methods on what people say is important. A random sample of 201 Wisconsin state employees who participated in a health plan choice experiment during the 1995 open enrollment period. We designed a computer system to guide subjects through the review of information about health plan options. The system began by eliciting the stated preferences of the subjects before they viewed the information, at time 0. Subjects were given an opportunity to revise their preference structures first after viewing summary information about four health plans (time 1) and then after viewing more extensive, detailed information about the same options (time 2). At time 2, these individuals were also asked to rate the relative importance of a predefined list of health plan features presented to them. Data were collected on the number of attributes listed at each point in time and the importance weightings assigned to each attribute. In addition, each item on the attribute list was content analyzed. The provision of information changes the preference structures of individuals. Costs (price) and coverage dominated the attributes cited both before and after looking at health plan information. When presented with information on costs, quality, and how plans work, many of these relatively well educated consumers revised their preference structures; yet coverage and costs remained the primary cited attributes. Although efforts to provide health plan information should continue, decisions on the information to provide and on making it available are not enough. Individuals need help in understanding, processing, and using the information to construct their preferences and make better decisions.

  18. Computational path planner for product assembly in complex environments

    NASA Astrophysics Data System (ADS)

    Shang, Wei; Liu, Jianhua; Ning, Ruxin; Liu, Mi

    2013-03-01

    Assembly path planning is a crucial problem in assembly related design and manufacturing processes. Sampling based motion planning algorithms are used for computational assembly path planning. However, the performance of such algorithms may degrade much in environments with complex product structure, narrow passages or other challenging scenarios. A computational path planner for automatic assembly path planning in complex 3D environments is presented. The global planning process is divided into three phases based on the environment and specific algorithms are proposed and utilized in each phase to solve the challenging issues. A novel ray test based stochastic collision detection method is proposed to evaluate the intersection between two polyhedral objects. This method avoids fake collisions in conventional methods and degrades the geometric constraint when a part has to be removed with surface contact with other parts. A refined history based rapidly-exploring random tree (RRT) algorithm which bias the growth of the tree based on its planning history is proposed and employed in the planning phase where the path is simple but the space is highly constrained. A novel adaptive RRT algorithm is developed for the path planning problem with challenging scenarios and uncertain environment. With extending values assigned on each tree node and extending schemes applied, the tree can adapts its growth to explore complex environments more efficiently. Experiments on the key algorithms are carried out and comparisons are made between the conventional path planning algorithms and the presented ones. The comparing results show that based on the proposed algorithms, the path planner can compute assembly path in challenging complex environments more efficiently and with higher success. This research provides the references to the study of computational assembly path planning under complex environments.

  19. Recruitment, screening, and baseline participant characteristics in the WALK 2.0 study: A randomized controlled trial using web 2.0 applications to promote physical activity.

    PubMed

    Caperchione, Cristina M; Duncan, Mitch J; Rosenkranz, Richard R; Vandelanotte, Corneel; Van Itallie, Anetta K; Savage, Trevor N; Hooker, Cindy; Maeder, Anthony J; Mummery, W Kerry; Kolt, Gregory S

    2016-04-15

    To describe in detail the recruitment methods and enrollment rates, the screening methods, and the baseline characteristics of a sample of adults participating in the Walk 2.0 Study, an 18 month, 3-arm randomized controlled trial of a Web 2.0 based physical activity intervention. A two-fold recruitment plan was developed and implemented, including a direct mail-out to an extract from the Australian Electoral Commission electoral roll, and other supplementary methods including email and telephone. Physical activity screening involved two steps: a validated single-item self-report instrument and the follow-up Active Australia Questionnaire. Readiness for physical activity participation was also based on a two-step process of administering the Physical Activity Readiness Questionnaire and, where needed, further clearance from a medical practitioner. Across all recruitment methods, a total of 1244 participants expressed interest in participating, of which 656 were deemed eligible. Of these, 504 were later enrolled in the Walk 2.0 trial (77% enrollment rate) and randomized to the Walk 1.0 group (n = 165), the Walk 2.0 group (n = 168), or the Logbook group (n = 171). Mean age of the total sample was 50.8 years, with 65.2% female and 79.1% born in Australia. The results of this recruitment process demonstrate the successful use of multiple strategies to obtain a diverse sample of adults eligible to take part in a web-based physical activity promotion intervention. The use of dual screening processes ensured safe participation in the intervention. This approach to recruitment and physical activity screening can be used as a model for further trials in this area.

  20. Designing a multiple dependent state sampling plan based on the coefficient of variation.

    PubMed

    Yan, Aijun; Liu, Sanyang; Dong, Xiaojuan

    2016-01-01

    A multiple dependent state (MDS) sampling plan is developed based on the coefficient of variation of the quality characteristic which follows a normal distribution with unknown mean and variance. The optimal plan parameters of the proposed plan are solved by a nonlinear optimization model, which satisfies the given producer's risk and consumer's risk at the same time and minimizes the sample size required for inspection. The advantages of the proposed MDS sampling plan over the existing single sampling plan are discussed. Finally an example is given to illustrate the proposed plan.

  1. 7 CFR 42.104 - Sampling plans and defects.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Sampling plans and defects. 42.104 Section 42.104... REGULATIONS STANDARDS FOR CONDITION OF FOOD CONTAINERS Procedures for Stationary Lot Sampling and Inspection § 42.104 Sampling plans and defects. (a) Sampling plans. Sections 42.109 through 42.111 show the number...

  2. 7 CFR 42.104 - Sampling plans and defects.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Sampling plans and defects. 42.104 Section 42.104... REGULATIONS STANDARDS FOR CONDITION OF FOOD CONTAINERS Procedures for Stationary Lot Sampling and Inspection § 42.104 Sampling plans and defects. (a) Sampling plans. Sections 42.109 through 42.111 show the number...

  3. Statistical analysis plan for the Pneumatic CompREssion for PreVENting Venous Thromboembolism (PREVENT) trial: a study protocol for a randomized controlled trial.

    PubMed

    Arabi, Yaseen; Al-Hameed, Fahad; Burns, Karen E A; Mehta, Sangeeta; Alsolamy, Sami; Almaani, Mohammed; Mandourah, Yasser; Almekhlafi, Ghaleb A; Al Bshabshe, Ali; Finfer, Simon; Alshahrani, Mohammed; Khalid, Imran; Mehta, Yatin; Gaur, Atul; Hawa, Hassan; Buscher, Hergen; Arshad, Zia; Lababidi, Hani; Al Aithan, Abdulsalam; Jose, Jesna; Abdukahil, Sheryl Ann I; Afesh, Lara Y; Dbsawy, Maamoun; Al-Dawood, Abdulaziz

    2018-03-15

    The Pneumatic CompREssion for Preventing VENous Thromboembolism (PREVENT) trial evaluates the effect of adjunctive intermittent pneumatic compression (IPC) with pharmacologic thromboprophylaxis compared to pharmacologic thromboprophylaxis alone on venous thromboembolism (VTE) in critically ill adults. In this multicenter randomized trial, critically ill patients receiving pharmacologic thromboprophylaxis will be randomized to an IPC or a no IPC (control) group. The primary outcome is "incident" proximal lower-extremity deep vein thrombosis (DVT) within 28 days after randomization. Radiologists interpreting the lower-extremity ultrasonography will be blinded to intervention allocation, whereas the patients and treating team will be unblinded. The trial has 80% power to detect a 3% absolute risk reduction in the rate of proximal DVT from 7% to 4%. Consistent with international guidelines, we have developed a detailed plan to guide the analysis of the PREVENT trial. This plan specifies the statistical methods for the evaluation of primary and secondary outcomes, and defines covariates for adjusted analyses a priori. Application of this statistical analysis plan to the PREVENT trial will facilitate unbiased analyses of clinical data. ClinicalTrials.gov , ID: NCT02040103 . Registered on 3 November 2013; Current controlled trials, ID: ISRCTN44653506 . Registered on 30 October 2013.

  4. [Effectiveness of the "Five-Day Plan to Stop Smoking" in a city in Argentina].

    PubMed

    Alfaro, Mariana Elizabeth; Simi, Marcelo Ricardo

    2007-05-01

    To evaluate the effectiveness of the "Five-Day Plan to Stop Smoking" at the end of the intervention and after one year in a sample of participants in the city of Rosario, Santa Fe, Argentina. The quasi-experimental, longitudinal, prospective cohort, comparative study was based on the evaluation of the effectiveness of the "Five-Day Plan to Stop Smoking" in Rosario, Argentina, with eight groups of participants. Each session of the five-night course included presentations on medical aspects of smoking, an emphasis on group support in quitting, and relaxation techniques. The eight groups included a total of 739 people (50.5% of them women and 49.5% men). Using a sample of 281 participants who were chosen at random, effectiveness was evaluated immediately after the end of each course and again after one year. Effectiveness was assessed in relation to the age the subjects began smoking, the average daily consumption of cigarettes, the number of years participants had smoked, their educational level, the number of previous attempts to quit smoking, and the level of nicotine dependence as measured by the Fagerström scale. Association among qualitative variables was determined using relative risk (RR), with 95% confidence intervals. Differences in the means of quantitative variables were determined using the t test for independent samples. The chi-square test was used to establish differences among the categorical variables studied. Of the 281 participants (138 men and 143 women) in the sample, 201 (71.5%) (104 men and 97 women) quit smoking by the end of the course, and 77 (27.4%) (48 men and 29 women) did not smoke after one year. There was a significant association between relapse and female gender (RR = 1.22; P = 0.005), as was there for a score > or = 7 on the Fagerström scale of nicotine dependence (RR = 1.17; P = 0.03). Beginning to smoke before the age of 20 was a protective factor against relapse among those attending the "Five-Day Plan to Stop Smoking" courses. The most frequent determinants of relapse were abstinence syndrome symptoms (40.3%) and stressful situations (28.2%). The "Five-Day Plan to Stop Smoking" is an effective tool for secondary prevention of smoking. In the study population its effectiveness was associated with male gender and with a lower level of nicotine dependence.

  5. Nurse Family Partnership: Comparing Costs per Family in Randomized Trials Versus Scale-Up.

    PubMed

    Miller, Ted R; Hendrie, Delia

    2015-12-01

    The literature that addresses cost differences between randomized trials and full-scale replications is quite sparse. This paper examines how costs differed among three randomized trials and six statewide scale-ups of nurse family partnership (NFP) intensive home visitation to low income first-time mothers. A literature review provided data on pertinent trials. At our request, six well-established programs reported their total expenditures. We adjusted the costs to national prices based on mean hourly wages for registered nurses and then inflated them to 2010 dollars. A centralized data system provided utilization. Replications had fewer home visits per family than trials (25 vs. 31, p = .05), lower costs per client ($8860 vs. $12,398, p = .01), and lower costs per visit ($354 vs. $400, p = .30). Sample size limited the significance of these differences. In this type of labor intensive program, costs probably were lower in scale-up than in randomized trials. Key cost drivers were attrition and the stable caseload size possible in an ongoing program. Our estimates reveal a wide variation in cost per visit across six state programs, which suggests that those planning replications should not expect a simple rule to guide cost estimations for scale-ups. Nevertheless, NFP replications probably achieved some economies of scale.

  6. 7 CFR 275.11 - Sampling.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false Sampling. 275.11 Section 275.11 Agriculture... § 275.11 Sampling. (a) Sampling plan. Each State agency shall develop a quality control sampling plan which demonstrates the integrity of its sampling procedures. (1) Content. The sampling plan shall...

  7. 7 CFR 275.11 - Sampling.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 4 2011-01-01 2011-01-01 false Sampling. 275.11 Section 275.11 Agriculture... § 275.11 Sampling. (a) Sampling plan. Each State agency shall develop a quality control sampling plan which demonstrates the integrity of its sampling procedures. (1) Content. The sampling plan shall...

  8. Assessment of effectiveness of smoking cessation intervention among male prisoners in India: A randomized controlled trial

    PubMed Central

    Naik, Sachin; Khanagar, Sanjeev; Kumar, Amit; Ramachandra, Sujith; Vadavadagi, Sunil V.; Dhananjaya, Kiran Murthy

    2014-01-01

    Background: Tobacco smoking is an integral part of prison life and an established part of the culture. Little attention has been paid to prevention of smoking in prison. Approximately 70–80% of prisoners have been identified as current smokers. Aim: To assess the effectiveness of smoking cessation intervention among male prisoners at Central Jail, Bangalore city. Aim: To assess the effectiveness of smoking cessation intervention among male prisoners at Central Jail, Bangalore city. Materials and Methods: A randomized controlled trial was planned among male prisoners in Central Jail, Bangalore city. There were 1600 convicted prisoners. A self-administered questionnaire was given to the prisoners to assess their smoking behavior by which prevalence of tobacco smoking was found. Exactly 1352 tobacco users were studied. Among them, there were 1252 smokers. Based on inclusion criteria and informed consent given by the prisoners, a sample of 600 was chosen for the study by systematic random sampling. Among the 600 prisoners, 300 were randomly selected for the study group and 300 for the control group. Results: Prevalence of tobacco smoking among the prisoners was 92.60%. In the present study, after smoking cessation intervention, 17% showed no change in smoking, 21.66% reduced smoking, 16% stopped smoking, and 45.33% relapsed (P < 0.0001) at the end of 6-month follow-up in the study group. Conclusion: Tobacco use was high among the prisoners. Tobacco reduction is possible in the prison even if the living conditions are not favorable. Relatively high rate of relapse in our study indicates that some policies should be adopted to improve smokers’ information on consequences of tobacco on health and motivational intervention should be added to prisoners. PMID:25558450

  9. Assessment of effectiveness of smoking cessation intervention among male prisoners in India: A randomized controlled trial.

    PubMed

    Naik, Sachin; Khanagar, Sanjeev; Kumar, Amit; Ramachandra, Sujith; Vadavadagi, Sunil V; Dhananjaya, Kiran Murthy

    2014-12-01

    Tobacco smoking is an integral part of prison life and an established part of the culture. Little attention has been paid to prevention of smoking in prison. Approximately 70-80% of prisoners have been identified as current smokers. To assess the effectiveness of smoking cessation intervention among male prisoners at Central Jail, Bangalore city. To assess the effectiveness of smoking cessation intervention among male prisoners at Central Jail, Bangalore city. A randomized controlled trial was planned among male prisoners in Central Jail, Bangalore city. There were 1600 convicted prisoners. A self-administered questionnaire was given to the prisoners to assess their smoking behavior by which prevalence of tobacco smoking was found. Exactly 1352 tobacco users were studied. Among them, there were 1252 smokers. Based on inclusion criteria and informed consent given by the prisoners, a sample of 600 was chosen for the study by systematic random sampling. Among the 600 prisoners, 300 were randomly selected for the study group and 300 for the control group. Prevalence of tobacco smoking among the prisoners was 92.60%. In the present study, after smoking cessation intervention, 17% showed no change in smoking, 21.66% reduced smoking, 16% stopped smoking, and 45.33% relapsed (P < 0.0001) at the end of 6-month follow-up in the study group. Tobacco use was high among the prisoners. Tobacco reduction is possible in the prison even if the living conditions are not favorable. Relatively high rate of relapse in our study indicates that some policies should be adopted to improve smokers' information on consequences of tobacco on health and motivational intervention should be added to prisoners.

  10. Treatment of Suicide Attempters With Bipolar Disorder: A Randomized Clinical Trial Comparing Lithium and Valproate in the Prevention of Suicidal Behavior

    PubMed Central

    Oquendo, Maria A.; Galfalvy, Hanga C.; Currier, Dianne; Grunebaum, Michael F.; Sher, Leo; Sullivan, Gregory M.; Burke, Ainsley K.; Harkavy-Friedman, Jill; Sublette, M. Elizabeth; Parsey, Ramin V.; Mann, J. John

    2013-01-01

    Objective Bipolar disorder is associated with high risk for suicidal acts. Observational studies suggest a protective effect of lithium against suicidal behavior. However, testing this effect in randomized clinical trials is logistically and ethically challenging. The authors tested the hypothesis that lithium offers bipolar patients with a history of suicide attempt greater protection against suicidal behavior compared to valproate. Method Patients with bipolar disorder and past suicide attempts (N=98) were randomly assigned to treatment with lithium or valproate, plus adjunctive medications as indicated, in a double-blind 2.5-year trial. An intent-to-treat analysis was performed using the log-rank test for survival data. Two models were fitted: time to suicide attempt and time to suicide event (attempt or hospitalization or change in medication in response to suicide plans). Results There were 45 suicide events in 35 participants, including 18 suicide attempts made by 14 participants, six from the lithium group and eight from the valproate group. There were no suicides. Intent-to-treat analysis using the log-rank test showed no differences between treatment groups in time to suicide attempt or to suicide event. Post hoc power calculations revealed that the modest sample size, reflective of challenges in recruitment, only permits detection of a relative risk of 5 or greater. Conclusions Despite the high frequency of suicide events during the study, this randomized controlled trial detected no difference between lithium and valproate in time to suicide attempt or suicide event in a sample of suicide attempters with bipolar disorder. However, smaller clinically significant differences between the two drugs were not ruled out. PMID:21768611

  11. Availability and Quality of Family Planning Services in the Democratic Republic of the Congo: High Potential for Improvement.

    PubMed

    Mpunga, Dieudonné; Lumbayi, J P; Dikamba, Nelly; Mwembo, Albert; Ali Mapatano, Mala; Wembodinga, Gilbert

    2017-06-27

    To determine the availability and quality of family planning services within health facilities throughout the Democratic Republic of the Congo (DRC). Data were collected for the cross-sectional study from April 2014 to June 2014 by the Ministry of Public Health. A total of 1,568 health facilities that reported data to the National Health Information System were selected by multistage random sampling in the 11 provinces of the DRC existing at that time. Data were collected through interviews, document review, and direct observation. Two dependent variables were measured: availability of family planning services (consisting of a room for services, staff assigned to family planning, and evidence of client use of family planning) and quality of family planning services (assessed as "high" if the facility had at least 1 trained staff member, family planning service delivery guidelines, at least 3 types of methods, and a sphygmomanometer, or "low" if the facility did not meet any of these 4 criteria). Pearson's chi-square test and odds ratios (ORs) were used to test for significant associations, using the alpha significance level of .05. We successfully surveyed 1,555 facilities (99.2%) of those included in the sample. One in every 3 facilities (33%) offered family planning services as assessed by the index of availability, of which 20% met all 4 criteria for providing high-quality services. Availability was greatest at the highest level of the health system (hospitals) and decreased incrementally with each health system level, with disparities between provinces and urban and rural areas. Facilities in urban areas were more likely than in rural areas to meet the standard for high-quality services ( P <.001). Public facilities were less likely than private facilities to have high-quality services ( P =.02). Among all 1,555 facilities surveyed, 14% had at least 3 types of methods available at the time of the survey; the most widely available methods were male condoms, combined oral contraceptive pills, and progestin-only injectable contraceptives. Availability and quality of family planning services in health facilities in the DRC remain low, with inequitable distribution of services throughout the country. To improve access to and use of family planning, efforts should focus on improving availability and quality at lower health system levels and in rural areas where the majority of the population lives. © Mpunga et al.

  12. Methodology Series Module 5: Sampling Strategies.

    PubMed

    Setia, Maninder Singh

    2016-01-01

    Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the ' Sampling Method'. There are essentially two types of sampling methods: 1) probability sampling - based on chance events (such as random numbers, flipping a coin etc.); and 2) non-probability sampling - based on researcher's choice, population that accessible & available. Some of the non-probability sampling methods are: purposive sampling, convenience sampling, or quota sampling. Random sampling method (such as simple random sample or stratified random sample) is a form of probability sampling. It is important to understand the different sampling methods used in clinical studies and mention this method clearly in the manuscript. The researcher should not misrepresent the sampling method in the manuscript (such as using the term ' random sample' when the researcher has used convenience sample). The sampling method will depend on the research question. For instance, the researcher may want to understand an issue in greater detail for one particular population rather than worry about the ' generalizability' of these results. In such a scenario, the researcher may want to use ' purposive sampling' for the study.

  13. A simple and efficient alternative to implementing systematic random sampling in stereological designs without a motorized microscope stage.

    PubMed

    Melvin, Neal R; Poda, Daniel; Sutherland, Robert J

    2007-10-01

    When properly applied, stereology is a very robust and efficient method to quantify a variety of parameters from biological material. A common sampling strategy in stereology is systematic random sampling, which involves choosing a random sampling [corrected] start point outside the structure of interest, and sampling relevant objects at [corrected] sites that are placed at pre-determined, equidistant intervals. This has proven to be a very efficient sampling strategy, and is used widely in stereological designs. At the microscopic level, this is most often achieved through the use of a motorized stage that facilitates the systematic random stepping across the structure of interest. Here, we report a simple, precise and cost-effective software-based alternative to accomplishing systematic random sampling under the microscope. We believe that this approach will facilitate the use of stereological designs that employ systematic random sampling in laboratories that lack the resources to acquire costly, fully automated systems.

  14. Planning, Recasts, and Learning of L2 Morphology

    ERIC Educational Resources Information Center

    Romanova, Natalia

    2010-01-01

    This study investigated two issues: (1) whether availability of planning time affects learners' ability to notice and learn from recasts in the input; and (2) whether pre-task or online planning is more effective. Participants were randomly assigned to three groups that formed the treatment conditions: a no planning group (N = 13), a pre-task…

  15. Actual distribution of Cronobacter spp. in industrial batches of powdered infant formula and consequences for performance of sampling strategies.

    PubMed

    Jongenburger, I; Reij, M W; Boer, E P J; Gorris, L G M; Zwietering, M H

    2011-11-15

    The actual spatial distribution of microorganisms within a batch of food influences the results of sampling for microbiological testing when this distribution is non-homogeneous. In the case of pathogens being non-homogeneously distributed, it markedly influences public health risk. This study investigated the spatial distribution of Cronobacter spp. in powdered infant formula (PIF) on industrial batch-scale for both a recalled batch as well a reference batch. Additionally, local spatial occurrence of clusters of Cronobacter cells was assessed, as well as the performance of typical sampling strategies to determine the presence of the microorganisms. The concentration of Cronobacter spp. was assessed in the course of the filling time of each batch, by taking samples of 333 g using the most probable number (MPN) enrichment technique. The occurrence of clusters of Cronobacter spp. cells was investigated by plate counting. From the recalled batch, 415 MPN samples were drawn. The expected heterogeneous distribution of Cronobacter spp. could be quantified from these samples, which showed no detectable level (detection limit of -2.52 log CFU/g) in 58% of samples, whilst in the remainder concentrations were found to be between -2.52 and 2.75 log CFU/g. The estimated average concentration in the recalled batch was -2.78 log CFU/g and a standard deviation of 1.10 log CFU/g. The estimated average concentration in the reference batch was -4.41 log CFU/g, with 99% of the 93 samples being below the detection limit. In the recalled batch, clusters of cells occurred sporadically in 8 out of 2290 samples of 1g taken. The two largest clusters contained 123 (2.09 log CFU/g) and 560 (2.75 log CFU/g) cells. Various sampling strategies were evaluated for the recalled batch. Taking more and smaller samples and keeping the total sampling weight constant, considerably improved the performance of the sampling plans to detect such a type of contaminated batch. Compared to random sampling, stratified random sampling improved the probability to detect the heterogeneous contamination. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Efficient sampling of complex network with modified random walk strategies

    NASA Astrophysics Data System (ADS)

    Xie, Yunya; Chang, Shuhua; Zhang, Zhipeng; Zhang, Mi; Yang, Lei

    2018-02-01

    We present two novel random walk strategies, choosing seed node (CSN) random walk and no-retracing (NR) random walk. Different from the classical random walk sampling, the CSN and NR strategies focus on the influences of the seed node choice and path overlap, respectively. Three random walk samplings are applied in the Erdös-Rényi (ER), Barabási-Albert (BA), Watts-Strogatz (WS), and the weighted USAir networks, respectively. Then, the major properties of sampled subnets, such as sampling efficiency, degree distributions, average degree and average clustering coefficient, are studied. The similar conclusions can be reached with these three random walk strategies. Firstly, the networks with small scales and simple structures are conducive to the sampling. Secondly, the average degree and the average clustering coefficient of the sampled subnet tend to the corresponding values of original networks with limited steps. And thirdly, all the degree distributions of the subnets are slightly biased to the high degree side. However, the NR strategy performs better for the average clustering coefficient of the subnet. In the real weighted USAir networks, some obvious characters like the larger clustering coefficient and the fluctuation of degree distribution are reproduced well by these random walk strategies.

  17. Methodology Series Module 5: Sampling Strategies

    PubMed Central

    Setia, Maninder Singh

    2016-01-01

    Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the ‘ Sampling Method’. There are essentially two types of sampling methods: 1) probability sampling – based on chance events (such as random numbers, flipping a coin etc.); and 2) non-probability sampling – based on researcher's choice, population that accessible & available. Some of the non-probability sampling methods are: purposive sampling, convenience sampling, or quota sampling. Random sampling method (such as simple random sample or stratified random sample) is a form of probability sampling. It is important to understand the different sampling methods used in clinical studies and mention this method clearly in the manuscript. The researcher should not misrepresent the sampling method in the manuscript (such as using the term ‘ random sample’ when the researcher has used convenience sample). The sampling method will depend on the research question. For instance, the researcher may want to understand an issue in greater detail for one particular population rather than worry about the ‘ generalizability’ of these results. In such a scenario, the researcher may want to use ‘ purposive sampling’ for the study. PMID:27688438

  18. Beyond fighting fires and chasing tails? Chronic illness care plans in Ontario, Canada.

    PubMed

    Russell, Grant; Thille, Patricia; Hogg, William; Lemelin, Jacques

    2008-01-01

    Recent work has conceptualized new models for the primary care management of patients with chronic illness. This study investigated the experience of family physicians and patients with a chronic illness management initiative that involved the joint formulation of comprehensive individual patient care plans. A qualitative evaluation, framed by phenomenology, immediately followed a randomized controlled trial examining the effect of external facilitators in enhancing the delivery of chronic condition care planning in primary care. The study, set in Ontario family practices, used semistructured in-depth interviews with a purposive sample of 13 family physicians, 20 patients, and all 3 study facilitators. Analysis used independent transcript review and constant comparative methods. Despite the intervention being grounded in patient-centered principles, family physicians generally viewed chronic illness management from a predominantly biomedical perspective. Only a few enthusiasts viewed systematic care planning as a new approach to managing patients with chronic illness. Most family physicians found the strategy to be difficult to implement within existing organizational and financial constraints. For these participants, care planning conflicted with preexisting concepts of their role and of their patient's abilities to become partners in care. The few patients who noticed the process spoke favorably about their experience. Although the experiences of the enthusiastic family physicians were encouraging, we found important individual-level barriers to chronic illness management in primary care. These issues seemed to transcend existing organizational and resource constraints.

  19. Sampling Strategies for Evaluating the Rate of Adventitious Transgene Presence in Non-Genetically Modified Crop Fields.

    PubMed

    Makowski, David; Bancal, Rémi; Bensadoun, Arnaud; Monod, Hervé; Messéan, Antoine

    2017-09-01

    According to E.U. regulations, the maximum allowable rate of adventitious transgene presence in non-genetically modified (GM) crops is 0.9%. We compared four sampling methods for the detection of transgenic material in agricultural non-GM maize fields: random sampling, stratified sampling, random sampling + ratio reweighting, random sampling + regression reweighting. Random sampling involves simply sampling maize grains from different locations selected at random from the field concerned. The stratified and reweighting sampling methods make use of an auxiliary variable corresponding to the output of a gene-flow model (a zero-inflated Poisson model) simulating cross-pollination as a function of wind speed, wind direction, and distance to the closest GM maize field. With the stratified sampling method, an auxiliary variable is used to define several strata with contrasting transgene presence rates, and grains are then sampled at random from each stratum. With the two methods involving reweighting, grains are first sampled at random from various locations within the field, and the observations are then reweighted according to the auxiliary variable. Data collected from three maize fields were used to compare the four sampling methods, and the results were used to determine the extent to which transgene presence rate estimation was improved by the use of stratified and reweighting sampling methods. We found that transgene rate estimates were more accurate and that substantially smaller samples could be used with sampling strategies based on an auxiliary variable derived from a gene-flow model. © 2017 Society for Risk Analysis.

  20. Sampling Large Graphs for Anticipatory Analytics

    DTIC Science & Technology

    2015-05-15

    low. C. Random Area Sampling Random area sampling [8] is a “ snowball ” sampling method in which a set of random seed vertices are selected and areas... Sampling Large Graphs for Anticipatory Analytics Lauren Edwards, Luke Johnson, Maja Milosavljevic, Vijay Gadepally, Benjamin A. Miller Lincoln...systems, greater human-in-the-loop involvement, or through complex algorithms. We are investigating the use of sampling to mitigate these challenges

  1. What Were They Thinking? Reducing Sunk-Cost Bias in a Life-Span Sample

    PubMed Central

    Strough, JoNell; Bruine de Bruin, Wändi; Parker, Andrew M.; Karns, Tara; Lemaster, Philip; Pichayayothin, Nipat; Delaney, Rebecca; Stoiko, Rachel

    2016-01-01

    We tested interventions to reduce “sunk-cost bias,” the tendency to continue investing in failing plans even when those plans have soured and are no longer rewarding. We showed members of a national U.S. life-span panel a hypothetical scenario about a failing plan that was halfway complete. Participants were randomly assigned to an intervention to focus on how to improve the situation, an intervention to focus on thoughts and feelings, or a no-intervention control group. First, we found that the thoughts and feelings intervention reduced sunk-cost bias in decisions about project completion, as compared to the improvement intervention and the no-intervention control. Second, older age was associated with greater willingness to cancel the failing plan across all three groups. Third, we found that introspection processes helped to explain the effectiveness of the interventions. Specifically, the larger reduction in sunk-cost bias as observed in the thoughts and feelings intervention (vs. the improvement intervention) was associated with suppression of future-oriented thoughts of eventual success, and with suppression of augmentations of the scenario that could make it seem reasonable to continue the plan. Fourth, we found that introspection processes were related to age differences in decisions. Older people were less likely to mention future-oriented thoughts of eventual success associated with greater willingness to continue the failing plan. We discuss factors to consider when designing interventions for reducing sunk-cost bias. PMID:27831712

  2. Electromagnetic Scattering by Fully Ordered and Quasi-Random Rigid Particulate Samples

    NASA Technical Reports Server (NTRS)

    Mishchenko, Michael I.; Dlugach, Janna M.; Mackowski, Daniel W.

    2016-01-01

    In this paper we have analyzed circumstances under which a rigid particulate sample can behave optically as a true discrete random medium consisting of particles randomly moving relative to each other during measurement. To this end, we applied the numerically exact superposition T-matrix method to model far-field scattering characteristics of fully ordered and quasi-randomly arranged rigid multiparticle groups in fixed and random orientations. We have shown that, in and of itself, averaging optical observables over movements of a rigid sample as a whole is insufficient unless it is combined with a quasi-random arrangement of the constituent particles in the sample. Otherwise, certain scattering effects typical of discrete random media (including some manifestations of coherent backscattering) may not be accurately replicated.

  3. Fixed-Precision Sequential Sampling Plans for Estimating Alfalfa Caterpillar, Colias lesbia, Egg Density in Alfalfa, Medicago sativa, Fields in Córdoba, Argentina

    PubMed Central

    Serra, Gerardo V.; Porta, Norma C. La; Avalos, Susana; Mazzuferi, Vilma

    2013-01-01

    The alfalfa caterpillar, Colias lesbia (Fabricius) (Lepidoptera: Pieridae), is a major pest of alfalfa, Medicago sativa L. (Fabales: Fabaceae), crops in Argentina. Its management is based mainly on chemical control of larvae whenever the larvae exceed the action threshold. To develop and validate fixed-precision sequential sampling plans, an intensive sampling programme for C. lesbia eggs was carried out in two alfalfa plots located in the Province of Córdoba, Argentina, from 1999 to 2002. Using Resampling for Validation of Sampling Plans software, 12 additional independent data sets were used to validate the sequential sampling plan with precision levels of 0.10 and 0.25 (SE/mean), respectively. For a range of mean densities of 0.10 to 8.35 eggs/sample, an average sample size of only 27 and 26 sample units was required to achieve a desired precision level of 0.25 for the sampling plans of Green and Kuno, respectively. As the precision level was increased to 0.10, average sample size increased to 161 and 157 sample units for the sampling plans of Green and Kuno, respectively. We recommend using Green's sequential sampling plan because it is less sensitive to changes in egg density. These sampling plans are a valuable tool for researchers to study population dynamics and to evaluate integrated pest management strategies. PMID:23909840

  4. Effectiveness of the Self-Regulation eHealth Intervention "MyPlan1.0." on Physical Activity Levels of Recently Retired Belgian Adults: A Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Van Dyck, Delfien; Plaete, Jolien; Cardon, Greet; Crombez, Geert; De Bourdeaudhuij, Ilse

    2016-01-01

    The study purpose was to test the effectiveness of the self-regulation eHealth intervention "MyPlan1.0." to increase physical activity (PA) in recently retired Belgian adults. This study was a randomized controlled trial with three points of follow-up/modules (baseline to 1-week to 1-month follow-up). In total, 240 recently retired…

  5. Pressing the Approach: A NASA Study of 19 Recent Accidents Yields a New Perspective on Pilot Error

    NASA Technical Reports Server (NTRS)

    Berman, Benjamin A.; Dismukes, R. Key

    2007-01-01

    This article begins with a review of two sample airplane accidents that were caused by pilot error. The analysis of these and 17 other accidents suggested that almost all experienced pilot operating in the same environment in which the accident crews were operating and knowing only what the accident crews knew at each moment of the flight, would be vulnerable to making a similar decision and similar errors. Whether a particular crew in a given situation makes errors depends on somewhat random interaction of factors. Two themes that seem to be prevalent in these cases are: Plan Continuation Bias, and Snowballing Workload.

  6. Medical resource preparation and allocation for humanitarian assistance based on module organization.

    PubMed

    Zhu, Min; Chen, Ruxue; Zhong, Shaobo; Qian, Yangming; Huang, Quanyi

    2017-02-01

    This research aims to associate the allocation of medical resources with the function of the modular organization and the possible needs for humanitarian assistance missions. The overseas humanitarian medical assistance mission, which was sent after a disaster on the hospital ship Peace Ark, part of China's People's Liberation Army (PLA) Navy, was considered as study model. The cases used for clustering and matching sample formation were randomly selected from the existing information related to Peace Ark's mission. Categories of the reusable resources clustered by this research met the requirement of the actual consumption almost completely (more than 95%) and the categories of non-reusable resources met the requirement by more than 80%. In the mission's original resource preparing plan, more than 30% of the non-reusable resource categories remained unused during the mission. In the original resource preparing plan, some key non-reusable resources inventories were completely exhausted at the end of the mission, while 5% to 30% of non-reusable resources remained in the resource allocation plan generated by this research at the end of the mission. The medical resource allocation plan generated here can enhance the supporting level for the humanitarian assistance mission. This research could lay the foundation for an assistant decision-making system for humanitarian assistance mission.

  7. Assessment of wadeable stream resources in the driftless area ecoregion in Western Wisconsin using a probabilistic sampling design.

    PubMed

    Miller, Michael A; Colby, Alison C C; Kanehl, Paul D; Blocksom, Karen

    2009-03-01

    The Wisconsin Department of Natural Resources (WDNR), with support from the U.S. EPA, conducted an assessment of wadeable streams in the Driftless Area ecoregion in western Wisconsin using a probabilistic sampling design. This ecoregion encompasses 20% of Wisconsin's land area and contains 8,800 miles of perennial streams. Randomly-selected stream sites (n = 60) equally distributed among stream orders 1-4 were sampled. Watershed land use, riparian and in-stream habitat, water chemistry, macroinvertebrate, and fish assemblage data were collected at each true random site and an associated "modified-random" site on each stream that was accessed via a road crossing nearest to the true random site. Targeted least-disturbed reference sites (n = 22) were also sampled to develop reference conditions for various physical, chemical, and biological measures. Cumulative distribution function plots of various measures collected at the true random sites evaluated with reference condition thresholds, indicate that high proportions of the random sites (and by inference the entire Driftless Area wadeable stream population) show some level of degradation. Study results show no statistically significant differences between the true random and modified-random sample sites for any of the nine physical habitat, 11 water chemistry, seven macroinvertebrate, or eight fish metrics analyzed. In Wisconsin's Driftless Area, 79% of wadeable stream lengths were accessible via road crossings. While further evaluation of the statistical rigor of using a modified-random sampling design is warranted, sampling randomly-selected stream sites accessed via the nearest road crossing may provide a more economical way to apply probabilistic sampling in stream monitoring programs.

  8. Challenges in the design of a Home Telemanagement trial for patients with ulcerative colitis.

    PubMed

    Cross, Raymond K; Finkelstein, Joseph

    2009-12-01

    Nonadherence, inadequate monitoring, and side-effects result in suboptimal outcomes in ulcerative colitis (UC). We hypothesize that telemanagement for UC will improve symptoms, quality of life, adherence, and decrease costs. This article describes the challenges encountered in the design of the home telemanagement in patients with UC trial. In a randomized trial to assess the effectiveness of telemanagement for UC compared to best available care, 100 patients will be enrolled. Subjects in the intervention arm will complete self-testing with telemanagement weekly; best available care subjects will receive scheduled follow up, educational fact sheets, and written action plans. Telemanagement consists of a home-unit, decision support server, and web-based clinician portal. The home-unit includes a scale and laptop. Subjects will respond to questions about symptoms, side-effects, adherence, and knowledge weekly; subjects will receive action plans after self-testing. Outcome variables to be assessed every 4 months include: disease activity, using the Seo index; quality of life, using the Inflammatory Bowel Disease Questionnaire; adherence, using pharmacy refill data and the Morisky Medication Adherence Scale; utilization of healthcare resources, using urgent care visits and hospitalizations. We encountered several challenges during design and implementation of our trial. First, we selected a randomized controlled trial design. We could have selected a quasiexperimental design to decrease the sample size needed and costs. Second, identification of a control group was challenging. Telemanagement patients received self-care plans and an educational curriculum. Since controls would not receive these interventions, we thought our results would be biased in favor of telemanagement. In addition, we wanted to evaluate the mode of delivery of these components of care. Therefore, we included written action plans and educational materials for patients in the control group ('best available care'). Third, we could not blind subjects to group assignment. In an attempt to decrease bias, staff was masked to group assignment to decrease measurement bias. Fourth, we selected outcome measures that were not invasive to decrease risks to subjects and to enhance recruitment. Our results may not be generalizable as our program is a tertiary center. Further, subjects are not blinded to the intervention potentially resulting in bias; we attempt to minimize this bias by having staff masked to treatment group at the time of assessment of outcome measures. To the best of our knowledge, our trial will be the first randomized controlled trial to evaluate telemedicine in subjects with gastrointestinal disease. We describe several issues encountered in design and implementation of our trial that will aid investigators when planning telemedicine trials in inflammatory bowel disease.

  9. Use of a low-literacy written action plan to improve parent understanding of pediatric asthma management: A randomized controlled study.

    PubMed

    Yin, Hsiang Shonna; Gupta, Ruchi S; Mendelsohn, Alan L; Dreyer, Benard; van Schaick, Linda; Brown, Christina R; Encalada, Karen; Sanchez, Dayana C; Warren, Christopher M; Tomopoulos, Suzy

    2017-11-01

    The objective of the study was to determine whether parents who use a low-literacy, pictogram- and photograph-based written asthma action plan (WAAP) have a better understanding of child asthma management compared to parents using a standard plan. A randomized controlled study was carried out in 2 urban pediatric outpatient clinics. Inclusion criteria were English- and Spanish-speaking parents of 2- to 12-year-old asthmatic children. Parents were randomized to receive a low-literacy or standard asthma action plan (American Academy of Allergy, Asthma and Immunology) for a hypothetical patient on controller and rescue medications. A structured questionnaire was used to assess whether there was an error in knowledge of (1) medications to give everyday and when sick, (2) need for spacer use, and (3) appropriate emergency response to give albuterol and seek medical help. Multiple logistic regression analyses were performed, adjusting for parent age, health literacy (Newest Vital Sign); child asthma severity, medications; and site. 217 parents were randomized (109 intervention and 108 control). Parents who received the low-literacy plan were (1) less likely to make an error in knowledge of medications to take everyday and when sick compared to parents who received the standard plan (63.0 vs. 77.3%, p = 0.03; adjusted odds ratio [AOR] = 0.5[95% confidence interval: 0.2-0.9]) and (2) less likely to make an error regarding spacer use (14.0 vs. 51.1%, p < 0.001; AOR = 0.1 [0.06-0.3]). No difference in error in appropriate emergency response was seen (43.1 vs. 48.1%, p = 0.5). Use of a low-literacy WAAP was associated with better parent understanding of asthma management. Further study is needed to assess whether the use of this action plan improves child asthma outcomes.

  10. PRagmatic trial Of Video Education in Nursing homes: The design and rationale for a pragmatic cluster randomized trial in the nursing home setting.

    PubMed

    Mor, Vincent; Volandes, Angelo E; Gutman, Roee; Gatsonis, Constantine; Mitchell, Susan L

    2017-04-01

    Background/Aims Nursing homes are complex healthcare systems serving an increasingly sick population. Nursing homes must engage patients in advance care planning, but do so inconsistently. Video decision support tools improved advance care planning in small randomized controlled trials. Pragmatic trials are increasingly employed in health services research, although not commonly in the nursing home setting to which they are well-suited. This report presents the design and rationale for a pragmatic cluster randomized controlled trial that evaluated the "real world" application of an Advance Care Planning Video Program in two large US nursing home healthcare systems. Methods PRagmatic trial Of Video Education in Nursing homes was conducted in 360 nursing homes (N = 119 intervention/N = 241 control) owned by two healthcare systems. Over an 18-month implementation period, intervention facilities were instructed to offer the Advance Care Planning Video Program to all patients. Control facilities employed usual advance care planning practices. Patient characteristics and outcomes were ascertained from Medicare Claims, Minimum Data Set assessments, and facility electronic medical record data. Intervention adherence was measured using a Video Status Report embedded into electronic medical record systems. The primary outcome was the number of hospitalizations/person-day alive among long-stay patients with advanced dementia or cardiopulmonary disease. The rationale for the approaches to facility randomization and recruitment, intervention implementation, population selection, data acquisition, regulatory issues, and statistical analyses are discussed. Results The large number of well-characterized candidate facilities enabled several unique design features including stratification on historical hospitalization rates, randomization prior to recruitment, and 2:1 control to intervention facilities ratio. Strong endorsement from corporate leadership made randomization prior to recruitment feasible with 100% participation of facilities randomized to the intervention arm. Critical regulatory issues included minimal risk determination, waiver of informed consent, and determination that nursing home providers were not engaged in human subjects research. Intervention training and implementation were initiated on 5 January 2016 using corporate infrastructures for new program roll-out guided by standardized training elements designed by the research team. Video Status Reports in facilities' electronic medical records permitted "real-time" adherence monitoring and corrective actions. The Centers for Medicare and Medicaid Services Virtual Research Data Center allowed for rapid outcomes ascertainment. Conclusion We must rigorously evaluate interventions to deliver more patient-focused care to an increasingly frail nursing home population. Video decision support is a practical approach to improve advance care planning. PRagmatic trial Of Video Education in Nursing homes has the potential to promote goal-directed care among millions of older Americans in nursing homes and establish a methodology for future pragmatic randomized controlled trials in this complex healthcare setting.

  11. Using the mixed media according to internet-based on the instructional multimedia for developing students' learning achievements in biology course on foundational cell issue of secondary students at the 10th grade level in Rangsit University demonstration school

    NASA Astrophysics Data System (ADS)

    Kangloan, Pichet; Chayaburakul, Kanokporn; Santiboon, Toansakul

    2018-01-01

    The aims of this research study were 1) to develop students' learning achievements in biology course on foundational cell issue, 2) to examine students' satisfactions of their learning activities through the mixed media according to internet-based multi-instruction in biology on foundational cell issue at the 10th grade level were used in the first semester in the academic year 2014, which a sample size of 17 students in Rangsit University Demonstration School with cluster random sampling was selected. Students' learning administrations were instructed with the 3-instructional lesson plans according to the 5-Step Ladder Learning Management Plan (LLMP) namely; the maintaining lesson plan on the equilibrium of cell issue, a lesson plan for learning how to communicate between cell and cell division. Students' learning achievements were assessed with the 30-item Assessment of Learning Biology Test (ALBT), students' perceptions of their satisfactions were satisfied with the 20-item Questionnaire on Students Satisfaction (QSS), and students' learning activities were assessed with the Mixed Media Internet-Based Instruction (MMIBI) on foundational cell issue was designed. The results of this research study have found that: statistically significant of students' post-learning achievements were higher than their pre-learning outcomes and indicated that the differences were significant at the .05 level. Students' performances of their satisfaction to their perceptions toward biology class with the mixed media according to internet-based multi instruction in biology on foundational cell issue were the highest level and evidence of average mean score as 4.59.

  12. A digital smoking cessation program delivered through internet and cell phone without nicotine replacement (happy ending): randomized controlled trial.

    PubMed

    Brendryen, Håvar; Drozd, Filip; Kraft, Pål

    2008-11-28

    Happy Ending (HE) is an intense 1-year smoking cessation program delivered via the Internet and cell phone. HE consists of more than 400 contacts by email, Web pages, interactive voice response, and short message service technology. HE includes a craving helpline and a relapse prevention system, providing just-in-time therapy. All the components of the program are fully automated. The objectives were to describe the rationale for the design of HE, to assess the 12-month efficacy of HE in a sample of smokers willing to attempt to quit without the use of nicotine replacement therapy, and to explore the potential effect of HE on coping planning and self-efficacy (prior to quitting) and whether coping planning and self-efficacy mediate treatment effect. A two-arm randomized controlled trial was used. Subjects were recruited via Internet advertisements and randomly assigned to condition. Inclusion criteria were willingness to quit on a prescribed day without using nicotine replacement and being aged 18 years or older. The intervention group received HE, and the control group received a 44-page self-help booklet. Abstinence was defined as "not even a puff of smoke, for the last seven days" and was assessed by means of Internet surveys or telephone interviews 1, 3, 6, and 12 months postcessation. The main outcome was repeated point abstinence (ie, abstinence at all four time points). Coping planning and self-efficacy were measured at baseline and at the end of the preparation phase (ie, after 2 weeks of treatment, but prior to cessation day). A total of 290 participants received either the HE intervention (n=144) or the control booklet (n=146). Using intent-to-treat analysis, participants in the intervention group reported clinically and statistically significantly higher repeated point abstinence rates than control participants (20% versus 7%, odds ratio [OR] = 3.43, 95% CI = 1.60-7.34, P = .002). Although no differences were observed at baseline, by the end of the preparation phase, significantly higher levels of coping planning (t(261) = 3.07, P = .002) and precessation self-efficacy (t(261) = 2.63, P = .01) were observed in the intervention group compared with the control group. However, neither coping planning nor self-efficacy mediated long-term treatment effect. For point abstinence 1 month after quitting, however, coping planning and self-efficacy showed a partial mediation of the treatment effect. This 12-month trial documents a long-term treatment effect of a fully automated smoking cessation intervention without the use of nicotine replacement therapy. The study adds to the promise of using digital media in supporting behavior change.

  13. A random spatial sampling method in a rural developing nation

    Treesearch

    Michelle C. Kondo; Kent D.W. Bream; Frances K. Barg; Charles C. Branas

    2014-01-01

    Nonrandom sampling of populations in developing nations has limitations and can inaccurately estimate health phenomena, especially among hard-to-reach populations such as rural residents. However, random sampling of rural populations in developing nations can be challenged by incomplete enumeration of the base population. We describe a stratified random sampling method...

  14. Implementing trials of complex interventions in community settings: the USC-Rancho Los Amigos pressure ulcer prevention study (PUPS).

    PubMed

    Clark, Florence; Pyatak, Elizabeth A; Carlson, Mike; Blanche, Erna Imperatore; Vigen, Cheryl; Hay, Joel; Mallinson, Trudy; Blanchard, Jeanine; Unger, Jennifer B; Garber, Susan L; Diaz, Jesus; Florindez, Lucia I; Atkins, Michal; Rubayi, Salah; Azen, Stanley Paul

    2014-04-01

    Randomized trials of complex, non-pharmacologic interventions implemented in home and community settings, such as the University of Southern California (USC)-Rancho Los Amigos National Rehabilitation Center (RLANRC) Pressure Ulcer Prevention Study (PUPS), present unique challenges with respect to (1) participant recruitment and retention, (2) intervention delivery and fidelity, (3) randomization and assessment, and (4) potential inadvertent treatment effects. We describe the methods employed to address the challenges confronted in implementing PUPS. In this randomized controlled trial, we are assessing the efficacy of a complex, preventive intervention in reducing the incidence of, and costs associated with, the development of medically serious pressure ulcers in people with spinal cord injury. Individuals with spinal cord injury recruited from RLANRC were assigned to either a 12-month preventive intervention group or a standard care control group. The primary outcome is the incidence of serious pressure ulcers with secondary endpoints including ulcer-related surgeries, medical treatment costs, and quality of life. These outcomes are assessed at 12 and 24 months after randomization. Additionally, we are studying the mediating mechanisms that account for intervention outcomes. PUPS has been successfully implemented, including recruitment of the target sample size of 170 participants, assurance of the integrity of intervention protocol delivery with an average 90% treatment adherence rate, and enactment of the assessment plan. However, implementation has been replete with challenges. To meet recruitment goals, we instituted a five-pronged approach customized for an underserved, ethnically diverse population. In intervention delivery, we increased staff time to overcome economic and cultural barriers to retention and adherence. To ensure treatment fidelity and replicability, we monitored intervention protocol delivery in accordance with a rigorous plan. Finally, we have overcome unanticipated assessment and design concerns related to (1) determining pressure ulcer incidence/severity, (2) randomization imbalance, and (3) inadvertent potential control group contamination. We have addressed the most daunting challenges encountered in the recruitment, assessment, and intervention phases of PUPS. Some challenges and solutions may not apply to trials conducted in other settings. Overcoming challenges has required a multifaceted approach incorporating individualization, flexibility, and persistence, as well as the ability to implement needed mid-course corrections.

  15. Interest of LQAS method in a survey of HTLV-I infection in Benin (West Africa).

    PubMed

    Houinato, Dismand; Preux, Pierre-Marie; Charriere, Bénédicte; Massit, Bruno; Avodé, Gilbert; Denis, François; Dumas, Michel; Boutros-Toni, Fernand; Salamon, Roger

    2002-02-01

    HTLV-I is heterogeneously distributed in Sub-Saharan Africa. Traditional survey methods as cluster sampling could provide information for a country or region of interest. However, they cannot identify small areas with higher prevalences of infection to help in the health policy planning. Identification of such areas could be done by a Lot Quality Assurance Sampling (LQAS) method, which is currently used in industry to identify a poor performance in assembly lines. The LQAS method was used in Atacora (Northern Benin) between March and May 1998 to identify areas with a HTLV-I seroprevalence higher than 4%. Sixty-five subjects were randomly selected in each of 36 communes (lots) of this department. Lots were classified as unacceptable when the sample contained at least one positive subject. The LQAS method identified 25 (69.4 %) communes with a prevalence higher than 4%. Using stratified sampling theory, the overall HTLV-I seroprevalence was 4.5% (95% CI: 3.6-5.4%). These data show the interest of LQAS method application under field conditions to detect clusters of infection.

  16. Generalizing the Network Scale-Up Method: A New Estimator for the Size of Hidden Populations*

    PubMed Central

    Feehan, Dennis M.; Salganik, Matthew J.

    2018-01-01

    The network scale-up method enables researchers to estimate the size of hidden populations, such as drug injectors and sex workers, using sampled social network data. The basic scale-up estimator offers advantages over other size estimation techniques, but it depends on problematic modeling assumptions. We propose a new generalized scale-up estimator that can be used in settings with non-random social mixing and imperfect awareness about membership in the hidden population. Further, the new estimator can be used when data are collected via complex sample designs and from incomplete sampling frames. However, the generalized scale-up estimator also requires data from two samples: one from the frame population and one from the hidden population. In some situations these data from the hidden population can be collected by adding a small number of questions to already planned studies. For other situations, we develop interpretable adjustment factors that can be applied to the basic scale-up estimator. We conclude with practical recommendations for the design and analysis of future studies. PMID:29375167

  17. WE-H-BRC-06: A Unified Machine-Learning Based Probabilistic Model for Automated Anomaly Detection in the Treatment Plan Data

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

    Chang, X; Liu, S; Kalet, A

    Purpose: The purpose of this work was to investigate the ability of a machine-learning based probabilistic approach to detect radiotherapy treatment plan anomalies given initial disease classes information. Methods In total we obtained 1112 unique treatment plans with five plan parameters and disease information from a Mosaiq treatment management system database for use in the study. The plan parameters include prescription dose, fractions, fields, modality and techniques. The disease information includes disease site, and T, M and N disease stages. A Bayesian network method was employed to model the probabilistic relationships between tumor disease information, plan parameters and an anomalymore » flag. A Bayesian learning method with Dirichlet prior was useed to learn the joint probabilities between dependent variables in error-free plan data and data with artificially induced anomalies. In the study, we randomly sampled data with anomaly in a specified anomaly space.We tested the approach with three groups of plan anomalies – improper concurrence of values of all five plan parameters and values of any two out of five parameters, and all single plan parameter value anomalies. Totally, 16 types of plan anomalies were covered by the study. For each type, we trained an individual Bayesian network. Results: We found that the true positive rate (recall) and positive predictive value (precision) to detect concurrence anomalies of five plan parameters in new patient cases were 94.45±0.26% and 93.76±0.39% respectively. To detect other 15 types of plan anomalies, the average recall and precision were 93.61±2.57% and 93.78±3.54% respectively. The computation time to detect the plan anomaly of each type in a new plan is ∼0.08 seconds. Conclusion: The proposed method for treatment plan anomaly detection was found effective in the initial tests. The results suggest that this type of models could be applied to develop plan anomaly detection tools to assist manual and automated plan checks. The senior author received research grants from ViewRay Inc. and Varian Medical System.« less

  18. A new statistic to express the uncertainty of kriging predictions for purposes of survey planning.

    NASA Astrophysics Data System (ADS)

    Lark, R. M.; Lapworth, D. J.

    2014-05-01

    It is well-known that one advantage of kriging for spatial prediction is that, given the random effects model, the prediction error variance can be computed a priori for alternative sampling designs. This allows one to compare sampling schemes, in particular sampling at different densities, and so to decide on one which meets requirements in terms of the uncertainty of the resulting predictions. However, the planning of sampling schemes must account not only for statistical considerations, but also logistics and cost. This requires effective communication between statisticians, soil scientists and data users/sponsors such as managers, regulators or civil servants. In our experience the latter parties are not necessarily able to interpret the prediction error variance as a measure of uncertainty for decision making. In some contexts (particularly the solution of very specific problems at large cartographic scales, e.g. site remediation and precision farming) it is possible to translate uncertainty of predictions into a loss function directly comparable with the cost incurred in increasing precision. Often, however, sampling must be planned for more generic purposes (e.g. baseline or exploratory geochemical surveys). In this latter context the prediction error variance may be of limited value to a non-statistician who has to make a decision on sample intensity and associated cost. We propose an alternative criterion for these circumstances to aid communication between statisticians and data users about the uncertainty of geostatistical surveys based on different sampling intensities. The criterion is the consistency of estimates made from two non-coincident instantiations of a proposed sample design. We consider square sample grids, one instantiation is offset from the second by half the grid spacing along the rows and along the columns. If a sample grid is coarse relative to the important scales of variation in the target property then the consistency of predictions from two instantiations is expected to be small, and can be increased by reducing the grid spacing. The measure of consistency is the correlation between estimates from the two instantiations of the sample grid, averaged over a grid cell. We call this the offset correlation, it can be calculated from the variogram. We propose that this measure is easier to grasp intuitively than the prediction error variance, and has the advantage of having an upper bound (1.0) which will aid its interpretation. This quality measure is illustrated for some hypothetical examples, considering both ordinary kriging and factorial kriging of the variable of interest. It is also illustrated using data on metal concentrations in the soil of north-east England.

  19. Long-Term Ecological Monitoring Field Sampling Plan for 2007

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

    T. Haney

    2007-07-31

    This field sampling plan describes the field investigations planned for the Long-Term Ecological Monitoring Project at the Idaho National Laboratory Site in 2007. This plan and the Quality Assurance Project Plan for Waste Area Groups 1, 2, 3, 4, 5, 6, 7, 10, and Removal Actions constitute the sampling and analysis plan supporting long-term ecological monitoring sampling in 2007. The data collected under this plan will become part of the long-term ecological monitoring data set that is being collected annually. The data will be used t determine the requirements for the subsequent long-term ecological monitoring. This plan guides the 2007more » investigations, including sampling, quality assurance, quality control, analytical procedures, and data management. As such, this plan will help to ensure that the resulting monitoring data will be scientifically valid, defensible, and of known and acceptable quality.« less

  20. Reduction of display artifacts by random sampling

    NASA Technical Reports Server (NTRS)

    Ahumada, A. J., Jr.; Nagel, D. C.; Watson, A. B.; Yellott, J. I., Jr.

    1983-01-01

    The application of random-sampling techniques to remove visible artifacts (such as flicker, moire patterns, and paradoxical motion) introduced in TV-type displays by discrete sequential scanning is discussed and demonstrated. Sequential-scanning artifacts are described; the window of visibility defined in spatiotemporal frequency space by Watson and Ahumada (1982 and 1983) and Watson et al. (1983) is explained; the basic principles of random sampling are reviewed and illustrated by the case of the human retina; and it is proposed that the sampling artifacts can be replaced by random noise, which can then be shifted to frequency-space regions outside the window of visibility. Vertical sequential, single-random-sequence, and continuously renewed random-sequence plotting displays generating 128 points at update rates up to 130 Hz are applied to images of stationary and moving lines, and best results are obtained with the single random sequence for the stationary lines and with the renewed random sequence for the moving lines.

  1. Technology diffusion in hospitals: a log odds random effects regression model.

    PubMed

    Blank, Jos L T; Valdmanis, Vivian G

    2015-01-01

    This study identifies the factors that affect the diffusion of hospital innovations. We apply a log odds random effects regression model on hospital micro data. We introduce the concept of clustering innovations and the application of a log odds random effects regression model to describe the diffusion of technologies. We distinguish a number of determinants, such as service, physician, and environmental, financial and organizational characteristics of the 60 Dutch hospitals in our sample. On the basis of this data set on Dutch general hospitals over the period 1995-2002, we conclude that there is a relation between a number of determinants and the diffusion of innovations underlining conclusions from earlier research. Positive effects were found on the basis of the size of the hospitals, competition and a hospital's commitment to innovation. It appears that if a policy is developed to further diffuse innovations, the external effects of demand and market competition need to be examined, which would de facto lead to an efficient use of technology. For the individual hospital, instituting an innovations office appears to be the most prudent course of action. © 2013 The Authors. International Journal of Health Planning and Management published by John Wiley & Sons, Ltd.

  2. Estimating statistical uncertainty of Monte Carlo efficiency-gain in the context of a correlated sampling Monte Carlo code for brachytherapy treatment planning with non-normal dose distribution.

    PubMed

    Mukhopadhyay, Nitai D; Sampson, Andrew J; Deniz, Daniel; Alm Carlsson, Gudrun; Williamson, Jeffrey; Malusek, Alexandr

    2012-01-01

    Correlated sampling Monte Carlo methods can shorten computing times in brachytherapy treatment planning. Monte Carlo efficiency is typically estimated via efficiency gain, defined as the reduction in computing time by correlated sampling relative to conventional Monte Carlo methods when equal statistical uncertainties have been achieved. The determination of the efficiency gain uncertainty arising from random effects, however, is not a straightforward task specially when the error distribution is non-normal. The purpose of this study is to evaluate the applicability of the F distribution and standardized uncertainty propagation methods (widely used in metrology to estimate uncertainty of physical measurements) for predicting confidence intervals about efficiency gain estimates derived from single Monte Carlo runs using fixed-collision correlated sampling in a simplified brachytherapy geometry. A bootstrap based algorithm was used to simulate the probability distribution of the efficiency gain estimates and the shortest 95% confidence interval was estimated from this distribution. It was found that the corresponding relative uncertainty was as large as 37% for this particular problem. The uncertainty propagation framework predicted confidence intervals reasonably well; however its main disadvantage was that uncertainties of input quantities had to be calculated in a separate run via a Monte Carlo method. The F distribution noticeably underestimated the confidence interval. These discrepancies were influenced by several photons with large statistical weights which made extremely large contributions to the scored absorbed dose difference. The mechanism of acquiring high statistical weights in the fixed-collision correlated sampling method was explained and a mitigation strategy was proposed. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. DiAlert: a prevention program for overweight first degree relatives of type 2 diabetes patients: results of a pilot study to test feasibility and acceptability.

    PubMed

    Heideman, Wieke H; de Wit, Maartje; Middelkoop, Barend J C; Nierkens, Vera; Stronks, Karien; Verhoeff, Arnoud P; Snoek, Frank J

    2012-09-27

    Prevalence of type 2 diabetes mellitus is increasing due to lifestyle changes, particularly affecting those genetically at risk. We developed DiAlert as a targeted group-based intervention aimed to promote intrinsic motivation and action planning for lifestyle changes and weight loss in first degree relatives of patients with type 2 diabetes mellitus.The main objective of the pilot of the DiAlert intervention was to assess fidelity, feasibility and acceptability prior to starting the randomized controlled trial. Individuals with a family history of type 2 diabetes mellitus were self-identified and screened for eligibility. DiAlert consists of two group sessions. Feasibility, fidelity, acceptability and self-reported perceptions and behavioral determinants were evaluated in a pre-post study using questionnaires and observations. Determinants of behavior change were analyzed using paired-samples t tests and Wilcoxon signed rank tests. DiAlert was delivered to two groups of first degree relatives of patients with type 2 diabetes mellitus (N = 9 and N = 12). Feasibility and fidelity were confirmed. Overall, the DiAlert group sessions were positively evaluated (8.0 on a scale of 1 to 10) by participants. The intervention did not impact perceived susceptibility or worry about personal diabetes risk. Action planning with regard to changing diet and physical activity increased. DiAlert proved feasible and was well-accepted by participants. Positive trends in action planning indicate increased likelihood of actual behavior change following DiAlert. Testing the effectiveness in a randomized controlled trial is imperative. Netherlands National Trial Register (NTR): NTR2036.

  4. Reducing Unintended Pregnancies Through Web-Based Reproductive Life Planning and Contraceptive Action Planning among Privately Insured Women: Study Protocol for the MyNewOptions Randomized, Controlled Trial.

    PubMed

    Chuang, Cynthia H; Velott, Diana L; Weisman, Carol S; Sciamanna, Christopher N; Legro, Richard S; Chinchilli, Vernon M; Moos, Merry-K; Francis, Erica B; Confer, Lindsay N; Lehman, Erik B; Armitage, Christopher J

    2015-01-01

    The Affordable Care Act mandates that most women of reproductive age with private health insurance have full contraceptive coverage with no out-of-pocket costs, creating an actionable time for women to evaluate their contraceptive choices without cost considerations. The MyNewOptions study is a three-arm, randomized, controlled trial testing web-based interventions aimed at assisting privately insured women with making contraceptive choices that are consistent with their reproductive goals. Privately insured women between the ages of 18 and 40 not intending pregnancy were randomly assigned to one of three groups: 1) a reproductive life planning (RLP) intervention, 2) a reproductive life planning enriched with contraceptive action planning (RLP+) intervention, or 3) an information only control group. Both the RLP and RLP+ guide women to identify their individualized reproductive goals and contraceptive method requirements. The RLP+ additionally includes a contraceptive action planning component, which uses if-then scenarios that allow the user to problem solve situations that make it difficult to be adherent to their contraceptive method. All three groups have access to a reproductive options library containing information about their contraceptive coverage and the attributes of alternative contraceptive methods. Women completed a baseline survey with follow-up surveys every 6 months for 2 years concurrent with intervention boosters. Study outcomes include contraceptive use and adherence. ClinicalTrials.gov identifier: NCT02100124. Results from the MyNewOptions study will demonstrate whether web-based reproductive life planning, with or without contraceptive action planning, helps insured women make patient-centered contraceptive choices compared with an information-only control condition. Copyright © 2015 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

  5. Randomized controlled trial of a health plan-level mood disorders psychosocial intervention for solo or small practices.

    PubMed

    Kilbourne, Amy M; Nord, Kristina M; Kyle, Julia; Van Poppelen, Celeste; Goodrich, David E; Kim, Hyungjin Myra; Eisenberg, Daniel; Un, Hyong; Bauer, Mark S

    2014-01-01

    Mood disorders represent the most expensive mental disorders for employer-based commercial health plans. Collaborative care models are effective in treating chronic physical and mental illnesses at little to no net healthcare cost, but to date have primarily been implemented by larger healthcare organizations in facility-based models. The majority of practices providing commercially insured care are far too small to implement such models. Health plan-level collaborative care treatment can address this unmet need. The goal of this study is to implement at the national commercial health plan level a collaborative care model to improve outcomes for persons with mood disorders. A randomized controlled trial of a collaborative care model versus usual care will be conducted among beneficiaries of a large national health plan from across the country seen by primary care or behavioral health practices. At discharge 344 patients identified by health plan claims as hospitalized for unipolar depression or bipolar disorder will be randomized to receive collaborative care (patient phone-based self-management support, care management, and guideline dissemination to practices delivered by a plan-level care manager) or usual care from their provider. Primary outcomes are changes in mood symptoms and mental health-related quality of life at 12 months. Secondary outcomes include rehospitalization, receipt of guideline-concordant care, and work productivity. This study will determine whether a collaborative care model for mood disorders delivered at the national health plan level improves outcomes compared to usual care, and will inform a business case for collaborative care models for these settings that can reach patients wherever they receive treatment. ClinicalTrials.gov Identifier: NCT02041962; registered January 3, 2014.

  6. Effect of crisis response planning vs. contracts for safety on suicide risk in U.S. Army Soldiers: A randomized clinical trial.

    PubMed

    Bryan, Craig J; Mintz, Jim; Clemans, Tracy A; Leeson, Bruce; Burch, T Scott; Williams, Sean R; Maney, Emily; Rudd, M David

    2017-04-01

    To evaluate the effectiveness of crisis response planning for the prevention of suicide attempts. Randomized clinical trial of active duty Army Soldiers (N=97) at Fort Carson, Colorado, presenting for an emergency behavioral health appointment. Participants were randomly assigned to receive a contract for safety, a standard crisis response plan, or an enhanced crisis response plan. Incidence of suicide attempts during follow-up was assessed with the Suicide Attempt Self-Injury Interview. Inclusion criteria were the presence of suicidal ideation during the past week and/or a lifetime history of suicide attempt. Exclusion criteria were the presence of a medical condition that precluded informed consent (e.g., active psychosis, mania). Survival curve analyses were used to determine efficacy on time to first suicide attempt. Longitudinal mixed effects models were used to determine efficacy on severity of suicide ideation and follow-up mental health care utilization. From baseline to the 6-month follow-up, 3 participants receiving a crisis response plan (estimated proportion: 5%) and 5 participants receiving a contract for safety (estimated proportion: 19%) attempted suicide (log-rank χ 2 (1)=4.85, p=0.028; hazard ratio=0.24, 95% CI=0.06-0.96), suggesting a 76% reduction in suicide attempts. Crisis response planning was associated with significantly faster decline in suicide ideation (F(3,195)=18.64, p<0.001) and fewer inpatient hospitalization days (F(1,82)=7.41, p<0.001). There were no differences between the enhanced and standard crisis response plan conditions. Crisis response planning was more effective than a contract for safety in preventing suicide attempts, resolving suicide ideation, and reducing inpatient hospitalization among high-risk active duty Soldiers. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Workforce planning in dentistry: the impact of shorter and more varied career patterns.

    PubMed

    Newton, J T; Buck, D; Gibbons, D E

    2001-12-01

    To compare the frequency and duration of career breaks taken by three groups of dental health care professionals and to assess the impact of these and changes in working hours on human resource planning. Dental personnel planning has been the subject of recent attention, particularly the role of professionals complementary to dentistry. Data on which to plan a dental personnel strategy have been lacking. Questionnaire survey of a random sample of 10% of dental practitioners, and of all dental therapists and dental hygienists registered with the General Dental Council. The proportion of each group who had taken a career break at some point during their career was analysed for each professional group. A larger proportion of female general dental practitioners (61%) than male practitioners (27%) take a break in their career at some point during their working lives. The proportion of hygienists who take career breaks is similar (57%) to the proportion of female GDPs. The proportion of dental therapists who take a career break (who in this sample were all female) is 71%. The duration of career breaks taken by women is longer than that for males, the median length of career breaks for male dental practitioners is 4 months; female dental practitioners 9 months; hygienists 11 months; therapists 11.5 months. Female GDPs who take a career break can be expected to have a working life 25% shorter than a GDP who does not take a career break. As the proportion of female general dental practitioners increases, and with the possible expansion of the role of professionals complementary to dentistry, there is likely to be an increase in the proportion of dental personnel who take a career break during their working lives. Planning of dental personnel requirements should consider the likely effect of career breaks upon the availability of dental staff.

  8. Revisiting sample size: are big trials the answer?

    PubMed

    Lurati Buse, Giovanna A L; Botto, Fernando; Devereaux, P J

    2012-07-18

    The superiority of the evidence generated in randomized controlled trials over observational data is not only conditional to randomization. Randomized controlled trials require proper design and implementation to provide a reliable effect estimate. Adequate random sequence generation, allocation implementation, analyses based on the intention-to-treat principle, and sufficient power are crucial to the quality of a randomized controlled trial. Power, or the probability of the trial to detect a difference when a real difference between treatments exists, strongly depends on sample size. The quality of orthopaedic randomized controlled trials is frequently threatened by a limited sample size. This paper reviews basic concepts and pitfalls in sample-size estimation and focuses on the importance of large trials in the generation of valid evidence.

  9. The Futurist Perspective: Implications for Community College Planning.

    ERIC Educational Resources Information Center

    Nicholson, R. Stephen; Keyser, John S.

    Community college managers would probably acknowledge the importance of planning, but might not accept the need to adopt a futuristic perspective on educational planning. One of the characteristics of futurists is a belief that the future is a created reality, not a consequence of random events. Futurists conceive possible paths, examine…

  10. Reporting of analyses from randomized controlled trials with multiple arms: a systematic review.

    PubMed

    Baron, Gabriel; Perrodeau, Elodie; Boutron, Isabelle; Ravaud, Philippe

    2013-03-27

    Multiple-arm randomized trials can be more complex in their design, data analysis, and result reporting than two-arm trials. We conducted a systematic review to assess the reporting of analyses in reports of randomized controlled trials (RCTs) with multiple arms. The literature in the MEDLINE database was searched for reports of RCTs with multiple arms published in 2009 in the core clinical journals. Two reviewers extracted data using a standardized extraction form. In total, 298 reports were identified. Descriptions of the baseline characteristics and outcomes per group were missing in 45 reports (15.1%) and 48 reports (16.1%), respectively. More than half of the articles (n = 171, 57.4%) reported that a planned global test comparison was used (that is, assessment of the global differences between all groups), but 67 (39.2%) of these 171 articles did not report details of the planned analysis. Of the 116 articles reporting a global comparison test, 12 (10.3%) did not report the analysis as planned. In all, 60% of publications (n = 180) described planned pairwise test comparisons (that is, assessment of the difference between two groups), but 20 of these 180 articles (11.1%) did not report the pairwise test comparisons. Of the 204 articles reporting pairwise test comparisons, the comparisons were not planned for 44 (21.6%) of them. Less than half the reports (n = 137; 46%) provided baseline and outcome data per arm and reported the analysis as planned. Our findings highlight discrepancies between the planning and reporting of analyses in reports of multiple-arm trials.

  11. Comparison of the efficiency between two sampling plans for aflatoxins analysis in maize

    PubMed Central

    Mallmann, Adriano Olnei; Marchioro, Alexandro; Oliveira, Maurício Schneider; Rauber, Ricardo Hummes; Dilkin, Paulo; Mallmann, Carlos Augusto

    2014-01-01

    Variance and performance of two sampling plans for aflatoxins quantification in maize were evaluated. Eight lots of maize were sampled using two plans: manual, using sampling spear for kernels; and automatic, using a continuous flow to collect milled maize. Total variance and sampling, preparation, and analysis variance were determined and compared between plans through multifactor analysis of variance. Four theoretical distribution models were used to compare aflatoxins quantification distributions in eight maize lots. The acceptance and rejection probabilities for a lot under certain aflatoxin concentration were determined using variance and the information on the selected distribution model to build the operational characteristic curves (OC). Sampling and total variance were lower at the automatic plan. The OC curve from the automatic plan reduced both consumer and producer risks in comparison to the manual plan. The automatic plan is more efficient than the manual one because it expresses more accurately the real aflatoxin contamination in maize. PMID:24948911

  12. Adaptive pre-specification in randomized trials with and without pair-matching.

    PubMed

    Balzer, Laura B; van der Laan, Mark J; Petersen, Maya L

    2016-11-10

    In randomized trials, adjustment for measured covariates during the analysis can reduce variance and increase power. To avoid misleading inference, the analysis plan must be pre-specified. However, it is often unclear a priori which baseline covariates (if any) should be adjusted for in the analysis. Consider, for example, the Sustainable East Africa Research in Community Health (SEARCH) trial for HIV prevention and treatment. There are 16 matched pairs of communities and many potential adjustment variables, including region, HIV prevalence, male circumcision coverage, and measures of community-level viral load. In this paper, we propose a rigorous procedure to data-adaptively select the adjustment set, which maximizes the efficiency of the analysis. Specifically, we use cross-validation to select from a pre-specified library the candidate targeted maximum likelihood estimator (TMLE) that minimizes the estimated variance. For further gains in precision, we also propose a collaborative procedure for estimating the known exposure mechanism. Our small sample simulations demonstrate the promise of the methodology to maximize study power, while maintaining nominal confidence interval coverage. We show how our procedure can be tailored to the scientific question (intervention effect for the study sample vs. for the target population) and study design (pair-matched or not). Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Methods for estimating population density in data-limited areas: evaluating regression and tree-based models in Peru.

    PubMed

    Anderson, Weston; Guikema, Seth; Zaitchik, Ben; Pan, William

    2014-01-01

    Obtaining accurate small area estimates of population is essential for policy and health planning but is often difficult in countries with limited data. In lieu of available population data, small area estimate models draw information from previous time periods or from similar areas. This study focuses on model-based methods for estimating population when no direct samples are available in the area of interest. To explore the efficacy of tree-based models for estimating population density, we compare six different model structures including Random Forest and Bayesian Additive Regression Trees. Results demonstrate that without information from prior time periods, non-parametric tree-based models produced more accurate predictions than did conventional regression methods. Improving estimates of population density in non-sampled areas is important for regions with incomplete census data and has implications for economic, health and development policies.

  14. Methods for Estimating Population Density in Data-Limited Areas: Evaluating Regression and Tree-Based Models in Peru

    PubMed Central

    Anderson, Weston; Guikema, Seth; Zaitchik, Ben; Pan, William

    2014-01-01

    Obtaining accurate small area estimates of population is essential for policy and health planning but is often difficult in countries with limited data. In lieu of available population data, small area estimate models draw information from previous time periods or from similar areas. This study focuses on model-based methods for estimating population when no direct samples are available in the area of interest. To explore the efficacy of tree-based models for estimating population density, we compare six different model structures including Random Forest and Bayesian Additive Regression Trees. Results demonstrate that without information from prior time periods, non-parametric tree-based models produced more accurate predictions than did conventional regression methods. Improving estimates of population density in non-sampled areas is important for regions with incomplete census data and has implications for economic, health and development policies. PMID:24992657

  15. Levels of dioxins and dioxin-like PCBs in food of animal origin in the Netherlands during the period 2001-2011.

    PubMed

    Adamse, Paulien; Schoss, Stefanie; Theelen, Rob M C; Hoogenboom, Ron L A P

    2017-01-01

    The aim of this study was to assess levels of dioxins (polychlorinated dibenzo-p-dioxins and dibenzofurans, PCDD/Fs) and dioxin-like polychlorinated biphenyls (PCBs) (DL-PCBs) in food of animal origin produced in the Netherlands, including potential trends in time. Test results from about 2500 samples of animal derived food products (beef, veal, lamb, chicken, pork, deer, milk and eggs), sampled for the National Residue Monitoring Plan from 2001-2011, were evaluated. Most samples were screened with a bioassay and, if suspected, analysed by GC-HRMS. The fraction of samples which were non-compliant with European maximum levels was rather low, being below 1% for most food products, except for lamb. Exceedance of action levels was particularly observed for lamb and beef. To obtain an insight into background levels, a randomly taken part of the samples was directly analysed by GC-HRMS. In general, only minor decreases in mean PCDD/F and DL-PCB concentrations could be observed for the period 2001-2011. This may be due to a plateauing of current background levels but also to factors like the sensitivity of the analytical method.

  16. Intraherd correlation coefficients and design effects for bovine viral diarrhoea, infectious bovine rhinotracheitis, leptospirosis and neosporosis in cow-calf system herds in North-eastern Mexico.

    PubMed

    Segura-Correa, J C; Domínguez-Díaz, D; Avalos-Ramírez, R; Argaez-Sosa, J

    2010-09-01

    Knowledge of the intraherd correlation coefficient (ICC) and design (D) effect for infectious diseases could be of interest in sample size calculation and to provide the correct standard errors of prevalence estimates in cluster or two-stage samplings surveys. Information on 813 animals from 48 non-vaccinated cow-calf herds from North-eastern Mexico was used. The ICC for the bovine viral diarrhoea (BVD), infectious bovine rhinotracheitis (IBR), leptospirosis and neosporosis diseases were calculated using a Bayesian approach adjusting for the sensitivity and specificity of the diagnostic tests. The ICC and D values for BVD, IBR, leptospirosis and neosporosis were 0.31 and 5.91, 0.18 and 3.88, 0.22 and 4.53, and 0.11 and 2.68, respectively. The ICC and D values were different from 0 and D greater than 1, therefore large sample sizes are required to obtain the same precision in prevalence estimates than for a random simple sampling design. The report of ICC and D values is of great help in planning and designing two-stage sampling studies. 2010 Elsevier B.V. All rights reserved.

  17. [Comparison study on sampling methods of Oncomelania hupensis snail survey in marshland schistosomiasis epidemic areas in China].

    PubMed

    An, Zhao; Wen-Xin, Zhang; Zhong, Yao; Yu-Kuan, Ma; Qing, Liu; Hou-Lang, Duan; Yi-di, Shang

    2016-06-29

    To optimize and simplify the survey method of Oncomelania hupensis snail in marshland endemic region of schistosomiasis and increase the precision, efficiency and economy of the snail survey. A quadrate experimental field was selected as the subject of 50 m×50 m size in Chayegang marshland near Henghu farm in the Poyang Lake region and a whole-covered method was adopted to survey the snails. The simple random sampling, systematic sampling and stratified random sampling methods were applied to calculate the minimum sample size, relative sampling error and absolute sampling error. The minimum sample sizes of the simple random sampling, systematic sampling and stratified random sampling methods were 300, 300 and 225, respectively. The relative sampling errors of three methods were all less than 15%. The absolute sampling errors were 0.221 7, 0.302 4 and 0.047 8, respectively. The spatial stratified sampling with altitude as the stratum variable is an efficient approach of lower cost and higher precision for the snail survey.

  18. 7 CFR 43.103 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... SAMPLING PLANS Sampling Plans § 43.103 Purpose and scope. (a) This subpart contains selected single and double sampling plans for inspection by attributes. They are to serve as a source of plans for developing...

  19. An Exploratory Study of Spirituality in HIV Infected Adolescents and their Families: FAmily CEntered Advance Care Planning and Medication Adherence

    PubMed Central

    Lyon, Maureen E.; Garvie, Patricia A.; Kao, Ellin; Briggs, Linda; He, Jianping; Malow, Robert; D’Angelo, Lawrence J.; McCarter, Robert

    2010-01-01

    Purpose To explore the impact of spirituality and religious beliefs on FAmily CEntered (FACE) Advance Care Planning and medication adherence in HIV+ adolescents and their surrogate decision-makers. Methods A sample of HIV+ adolescents (n=40) and their surrogates, age 21 or older, (n=40) was randomized to an active Healthy Living Control group or the FACE Advance Care Planning intervention, guided by transactional stress and coping theory. Adolescents’ spirituality was assessed at baseline and 3 months post-intervention, using the FACIT-SP-4-EX, as was the belief that HIV is a punishment from God. Results Control adolescents increased faith and meaning/purpose more so than FACE adolescents (p=0.02). At baseline more behaviorally (16%) vs. perinatally (8%) infected adolescents believed HIV was a punishment from God, but not at 3-months post-intervention. Adolescents endorsing HIV was a punishment scored lower on spirituality (p=.05) and adherence to HAART (p= .04). Surrogates were more spiritual than adolescents (p=<.0001). Conclusion Providing family support in a friendly, facilitated, environment enhanced adolescents’ spirituality. Facilitated family conversations had an especially positive effect on behaviorally infected adolescents’ medication adherence and spiritual beliefs. PMID:21575826

  20. Attitudes, norms, identity and environmental behaviour: using an expanded theory of planned behaviour to predict participation in a kerbside recycling programme.

    PubMed

    Nigbur, Dennis; Lyons, Evanthia; Uzzell, David

    2010-06-01

    In an effort to contribute to greater understanding of norms and identity in the theory of planned behaviour, an extended model was used to predict residential kerbside recycling, with self-identity, personal norms, neighbourhood identification, and injunctive and descriptive social norms as additional predictors. Data from a field study (N=527) using questionnaire measures of predictor variables and an observational measure of recycling behaviour supported the theory. Intentions predicted behaviour, while attitudes, perceived control, and the personal norm predicted intention to recycle. The interaction between neighbourhood identification and injunctive social norms in turn predicted personal norms. Self-identity and the descriptive social norm significantly added to the original theory in predicting intentions as well as behaviour directly. A replication survey on the self-reported recycling behaviours of a random residential sample (N=264) supported the model obtained previously. These findings offer a useful extension of the theory of planned behaviour and some practicable suggestions for pro-recycling interventions. It may be productive to appeal to self-identity by making people feel like recyclers, and to stimulate both injunctive and descriptive norms in the neighbourhood.

  1. Smoothing the redshift distributions of random samples for the baryon acoustic oscillations: applications to the SDSS-III BOSS DR12 and QPM mock samples

    NASA Astrophysics Data System (ADS)

    Wang, Shao-Jiang; Guo, Qi; Cai, Rong-Gen

    2017-12-01

    We investigate the impact of different redshift distributions of random samples on the baryon acoustic oscillations (BAO) measurements of D_V(z)r_d^fid/r_d from the two-point correlation functions of galaxies in the Data Release 12 of the Baryon Oscillation Spectroscopic Survey (BOSS). Big surveys, such as BOSS, usually assign redshifts to the random samples by randomly drawing values from the measured redshift distributions of the data, which would necessarily introduce fiducial signals of fluctuations into the random samples, weakening the signals of BAO, if the cosmic variance cannot be ignored. We propose a smooth function of redshift distribution that fits the data well to populate the random galaxy samples. The resulting cosmological parameters match the input parameters of the mock catalogue very well. The significance of BAO signals has been improved by 0.33σ for a low-redshift sample and by 0.03σ for a constant-stellar-mass sample, though the absolute values do not change significantly. Given the precision of the measurements of current cosmological parameters, it would be appreciated for the future improvements on the measurements of galaxy clustering.

  2. Simulating recurrent event data with hazard functions defined on a total time scale.

    PubMed

    Jahn-Eimermacher, Antje; Ingel, Katharina; Ozga, Ann-Kathrin; Preussler, Stella; Binder, Harald

    2015-03-08

    In medical studies with recurrent event data a total time scale perspective is often needed to adequately reflect disease mechanisms. This means that the hazard process is defined on the time since some starting point, e.g. the beginning of some disease, in contrast to a gap time scale where the hazard process restarts after each event. While techniques such as the Andersen-Gill model have been developed for analyzing data from a total time perspective, techniques for the simulation of such data, e.g. for sample size planning, have not been investigated so far. We have derived a simulation algorithm covering the Andersen-Gill model that can be used for sample size planning in clinical trials as well as the investigation of modeling techniques. Specifically, we allow for fixed and/or random covariates and an arbitrary hazard function defined on a total time scale. Furthermore we take into account that individuals may be temporarily insusceptible to a recurrent incidence of the event. The methods are based on conditional distributions of the inter-event times conditional on the total time of the preceeding event or study start. Closed form solutions are provided for common distributions. The derived methods have been implemented in a readily accessible R script. The proposed techniques are illustrated by planning the sample size for a clinical trial with complex recurrent event data. The required sample size is shown to be affected not only by censoring and intra-patient correlation, but also by the presence of risk-free intervals. This demonstrates the need for a simulation algorithm that particularly allows for complex study designs where no analytical sample size formulas might exist. The derived simulation algorithm is seen to be useful for the simulation of recurrent event data that follow an Andersen-Gill model. Next to the use of a total time scale, it allows for intra-patient correlation and risk-free intervals as are often observed in clinical trial data. Its application therefore allows the simulation of data that closely resemble real settings and thus can improve the use of simulation studies for designing and analysing studies.

  3. Dispersion and sampling of adult Dermacentor andersoni in rangeland in Western North America.

    PubMed

    Rochon, K; Scoles, G A; Lysyk, T J

    2012-03-01

    A fixed precision sampling plan was developed for off-host populations of adult Rocky Mountain wood tick, Dermacentor andersoni (Stiles) based on data collected by dragging at 13 locations in Alberta, Canada; Washington; and Oregon. In total, 222 site-date combinations were sampled. Each site-date combination was considered a sample, and each sample ranged in size from 86 to 250 10 m2 quadrats. Analysis of simulated quadrats ranging in size from 10 to 50 m2 indicated that the most precise sample unit was the 10 m2 quadrat. Samples taken when abundance < 0.04 ticks per 10 m2 were more likely to not depart significantly from statistical randomness than samples taken when abundance was greater. Data were grouped into ten abundance classes and assessed for fit to the Poisson and negative binomial distributions. The Poisson distribution fit only data in abundance classes < 0.02 ticks per 10 m2, while the negative binomial distribution fit data from all abundance classes. A negative binomial distribution with common k = 0.3742 fit data in eight of the 10 abundance classes. Both the Taylor and Iwao mean-variance relationships were fit and used to predict sample sizes for a fixed level of precision. Sample sizes predicted using the Taylor model tended to underestimate actual sample sizes, while sample sizes estimated using the Iwao model tended to overestimate actual sample sizes. Using a negative binomial with common k provided estimates of required sample sizes closest to empirically calculated sample sizes.

  4. Authorization of Animal Experiments Is Based on Confidence Rather than Evidence of Scientific Rigor

    PubMed Central

    Nathues, Christina; Würbel, Hanno

    2016-01-01

    Accumulating evidence indicates high risk of bias in preclinical animal research, questioning the scientific validity and reproducibility of published research findings. Systematic reviews found low rates of reporting of measures against risks of bias in the published literature (e.g., randomization, blinding, sample size calculation) and a correlation between low reporting rates and inflated treatment effects. That most animal research undergoes peer review or ethical review would offer the possibility to detect risks of bias at an earlier stage, before the research has been conducted. For example, in Switzerland, animal experiments are licensed based on a detailed description of the study protocol and a harm–benefit analysis. We therefore screened applications for animal experiments submitted to Swiss authorities (n = 1,277) for the rates at which the use of seven basic measures against bias (allocation concealment, blinding, randomization, sample size calculation, inclusion/exclusion criteria, primary outcome variable, and statistical analysis plan) were described and compared them with the reporting rates of the same measures in a representative sub-sample of publications (n = 50) resulting from studies described in these applications. Measures against bias were described at very low rates, ranging on average from 2.4% for statistical analysis plan to 19% for primary outcome variable in applications for animal experiments, and from 0.0% for sample size calculation to 34% for statistical analysis plan in publications from these experiments. Calculating an internal validity score (IVS) based on the proportion of the seven measures against bias, we found a weak positive correlation between the IVS of applications and that of publications (Spearman’s rho = 0.34, p = 0.014), indicating that the rates of description of these measures in applications partly predict their rates of reporting in publications. These results indicate that the authorities licensing animal experiments are lacking important information about experimental conduct that determines the scientific validity of the findings, which may be critical for the weight attributed to the benefit of the research in the harm–benefit analysis. Similar to manuscripts getting accepted for publication despite poor reporting of measures against bias, applications for animal experiments may often be approved based on implicit confidence rather than explicit evidence of scientific rigor. Our findings shed serious doubt on the current authorization procedure for animal experiments, as well as the peer-review process for scientific publications, which in the long run may undermine the credibility of research. Developing existing authorization procedures that are already in place in many countries towards a preregistration system for animal research is one promising way to reform the system. This would not only benefit the scientific validity of findings from animal experiments but also help to avoid unnecessary harm to animals for inconclusive research. PMID:27911892

  5. Authorization of Animal Experiments Is Based on Confidence Rather than Evidence of Scientific Rigor.

    PubMed

    Vogt, Lucile; Reichlin, Thomas S; Nathues, Christina; Würbel, Hanno

    2016-12-01

    Accumulating evidence indicates high risk of bias in preclinical animal research, questioning the scientific validity and reproducibility of published research findings. Systematic reviews found low rates of reporting of measures against risks of bias in the published literature (e.g., randomization, blinding, sample size calculation) and a correlation between low reporting rates and inflated treatment effects. That most animal research undergoes peer review or ethical review would offer the possibility to detect risks of bias at an earlier stage, before the research has been conducted. For example, in Switzerland, animal experiments are licensed based on a detailed description of the study protocol and a harm-benefit analysis. We therefore screened applications for animal experiments submitted to Swiss authorities (n = 1,277) for the rates at which the use of seven basic measures against bias (allocation concealment, blinding, randomization, sample size calculation, inclusion/exclusion criteria, primary outcome variable, and statistical analysis plan) were described and compared them with the reporting rates of the same measures in a representative sub-sample of publications (n = 50) resulting from studies described in these applications. Measures against bias were described at very low rates, ranging on average from 2.4% for statistical analysis plan to 19% for primary outcome variable in applications for animal experiments, and from 0.0% for sample size calculation to 34% for statistical analysis plan in publications from these experiments. Calculating an internal validity score (IVS) based on the proportion of the seven measures against bias, we found a weak positive correlation between the IVS of applications and that of publications (Spearman's rho = 0.34, p = 0.014), indicating that the rates of description of these measures in applications partly predict their rates of reporting in publications. These results indicate that the authorities licensing animal experiments are lacking important information about experimental conduct that determines the scientific validity of the findings, which may be critical for the weight attributed to the benefit of the research in the harm-benefit analysis. Similar to manuscripts getting accepted for publication despite poor reporting of measures against bias, applications for animal experiments may often be approved based on implicit confidence rather than explicit evidence of scientific rigor. Our findings shed serious doubt on the current authorization procedure for animal experiments, as well as the peer-review process for scientific publications, which in the long run may undermine the credibility of research. Developing existing authorization procedures that are already in place in many countries towards a preregistration system for animal research is one promising way to reform the system. This would not only benefit the scientific validity of findings from animal experiments but also help to avoid unnecessary harm to animals for inconclusive research.

  6. A random forest algorithm for nowcasting of intense precipitation events

    NASA Astrophysics Data System (ADS)

    Das, Saurabh; Chakraborty, Rohit; Maitra, Animesh

    2017-09-01

    Automatic nowcasting of convective initiation and thunderstorms has potential applications in several sectors including aviation planning and disaster management. In this paper, random forest based machine learning algorithm is tested for nowcasting of convective rain with a ground based radiometer. Brightness temperatures measured at 14 frequencies (7 frequencies in 22-31 GHz band and 7 frequencies in 51-58 GHz bands) are utilized as the inputs of the model. The lower frequency band is associated to the water vapor absorption whereas the upper frequency band relates to the oxygen absorption and hence, provide information on the temperature and humidity of the atmosphere. Synthetic minority over-sampling technique is used to balance the data set and 10-fold cross validation is used to assess the performance of the model. Results indicate that random forest algorithm with fixed alarm generation time of 30 min and 60 min performs quite well (probability of detection of all types of weather condition ∼90%) with low false alarms. It is, however, also observed that reducing the alarm generation time improves the threat score significantly and also decreases false alarms. The proposed model is found to be very sensitive to the boundary layer instability as indicated by the variable importance measure. The study shows the suitability of a random forest algorithm for nowcasting application utilizing a large number of input parameters from diverse sources and can be utilized in other forecasting problems.

  7. [Use of an index of social welfare for health planning at a municipal level].

    PubMed

    Ochoa-Díaz López, H; Sánchez-Pérez, H J; Martínez-Guzmán, L A

    1996-01-01

    This paper analyzes the relationship between a living standards index for small areas based on census data and information on morbidity and health care utilization. The information was gathered through a health interview survey of a random sample of 1 238 households from rural areas of Tlaxcala, Mexico. The population from localities with lower living standards showed significantly higher prevalences of morbidity and worse self-reported health status measures, as compared to localities with higher living standards. On the contrary, higher living standards were related with a greater utilization of health services. The approach proved to be useful in discriminating localities and areas of high and low prevalence of morbidity and utilization of health care services, which in turn could be used to identify those areas where needs are greatest. The implications of the results for health planning and resource allocation (based on population health needs and underlying social conditions) at the local level are discussed.

  8. Baby boomers' food shopping habits. Relationships with demographics and personal values.

    PubMed

    Worsley, Anthony; Wang, Wei C; Hunter, Wendy

    2010-12-01

    The purpose of this study was to examine baby boomers' food shopping behaviours and to investigate their relationships with demographics and personal values. A questionnaire concerning food shopping behaviours, personal values and demographics was mailed to a random sample of 2975 people aged 40-70 years in Victoria, Australia. Usable questionnaires of 1031 were obtained. Structural equation modelling was employed for data analyses. The analyses revealed that demographics and personal values influenced shopping behaviours via different pathways among male and female baby boomers. For example, self-direction positively impacted on shopping planning for men but negatively influenced price minimization for women. Among women only, age was positively related to shopping planning and negatively to price minimization. Thus, both personal values and demographics influenced baby boomers' shopping behaviours. Since values are more likely to be amenable to change than demographics, segmentation of the population via value orientations would facilitate targeted interventions to promote healthy food shopping. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Using the theory of planned behavior to predict mothers' intentions to vaccinate their daughters against HPV.

    PubMed

    Askelson, Natoshia M; Campo, Shelly; Lowe, John B; Smith, Sandi; Dennis, Leslie K; Andsager, Julie

    2010-06-01

    This study assessed mothers' intentions to vaccinate their daughters against human papillomavirus (HPV) using the theory of planned behavior (TPB). Experience with sexually transmitted infections (STIs), beliefs about the vaccine encouraging sexual activity, and perception of daughters' risk for HPV were also examined for a relationship with intention. A random sample of mothers in a rural, Midwestern state were mailed a survey with questions pertaining to the intention to vaccinate. Attitudes were the strongest predictor of mothers' intentions to vaccinate, but intentions were not high. Subjective norms also influence intention. Mothers' risk perceptions, experience with STIs, and beliefs about the vaccine encouraging sexual activity were not related to intention. Mothers' perceptions of the daughters' risks for HPV were surprisingly low. This research provides a foundation for designing interventions to increase HPV vaccination rates. Further research should explore ways to influence mothers' attitudes and to uncover the referent groups mothers refer to for vaccination behavior.

  10. Research on Robot Pose Control Technology Based on Kinematics Analysis Model

    NASA Astrophysics Data System (ADS)

    Liu, Dalong; Xu, Lijuan

    2018-01-01

    In order to improve the attitude stability of the robot, proposes an attitude control method of robot based on kinematics analysis model, solve the robot walking posture transformation, grasping and controlling the motion planning problem of robot kinematics. In Cartesian space analytical model, using three axis accelerometer, magnetometer and the three axis gyroscope for the combination of attitude measurement, the gyroscope data from Calman filter, using the four element method for robot attitude angle, according to the centroid of the moving parts of the robot corresponding to obtain stability inertia parameters, using random sampling RRT motion planning method, accurate operation to any position control of space robot, to ensure the end effector along a prescribed trajectory the implementation of attitude control. The accurate positioning of the experiment is taken using MT-R robot as the research object, the test robot. The simulation results show that the proposed method has better robustness, and higher positioning accuracy, and it improves the reliability and safety of robot operation.

  11. Computer-assisted versus non-computer-assisted preoperative planning of corrective osteotomy for extra-articular distal radius malunions: a randomized controlled trial.

    PubMed

    Leong, Natalie L; Buijze, Geert A; Fu, Eric C; Stockmans, Filip; Jupiter, Jesse B

    2010-12-14

    Malunion is the most common complication of distal radius fracture. It has previously been demonstrated that there is a correlation between the quality of anatomical correction and overall wrist function. However, surgical correction can be difficult because of the often complex anatomy associated with this condition. Computer assisted surgical planning, combined with patient-specific surgical guides, has the potential to improve pre-operative understanding of patient anatomy as well as intra-operative accuracy. For patients with malunion of the distal radius fracture, this technology could significantly improve clinical outcomes that largely depend on the quality of restoration of normal anatomy. Therefore, the objective of this study is to compare patient outcomes after corrective osteotomy for distal radius malunion with and without preoperative computer-assisted planning and peri-operative patient-specific surgical guides. This study is a multi-center randomized controlled trial of conventional planning versus computer-assisted planning for surgical correction of distal radius malunion. Adult patients with extra-articular malunion of the distal radius will be invited to enroll in our study. After providing informed consent, subjects will be randomized to two groups: one group will receive corrective surgery with conventional preoperative planning, while the other will receive corrective surgery with computer-assisted pre-operative planning and peri-operative patient specific surgical guides. In the computer-assisted planning group, a CT scan of the affected forearm as well as the normal, contralateral forearm will be obtained. The images will be used to construct a 3D anatomical model of the defect and patient-specific surgical guides will be manufactured. Outcome will be measured by DASH and PRWE scores, grip strength, radiographic measurements, and patient satisfaction at 3, 6, and 12 months postoperatively. Computer-assisted surgical planning, combined with patient-specific surgical guides, is a powerful new technology that has the potential to improve the accuracy and consistency of orthopaedic surgery. To date, the role of this technology in upper extremity surgery has not been adequately investigated, and it is unclear whether its use provides any significant clinical benefit over traditional preoperative imaging protocols. Our study will represent the first randomized controlled trial investigating the use of computer assisted surgery in corrective osteotomy for distal radius malunions. NCT01193010.

  12. Adequate margins for random setup uncertainties in head-and-neck IMRT

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

    Astreinidou, Eleftheria; Bel, Arjan; Raaijmakers, Cornelis P.J.

    2005-03-01

    Purpose: To investigate the effect of random setup uncertainties on the highly conformal dose distributions produced by intensity-modulated radiotherapy (IMRT) for clinical head-and-neck cancer patients and to determine adequate margins to account for those uncertainties. Methods and materials: We have implemented in our clinical treatment planning system the possibility of simulating normally distributed patient setup displacements, translations, and rotations. The planning CT data of 8 patients with Stage T1-T3N0M0 oropharyngeal cancer were used. The clinical target volumes of the primary tumor (CTV{sub primary}) and of the lymph nodes (CTV{sub elective}) were expanded by 0.0, 1.5, 3.0, and 5.0 mm inmore » all directions, creating the planning target volumes (PTVs). We performed IMRT dose calculation using our class solution for each PTV margin, resulting in the conventional static plans. Then, the system recalculated the plan for each positioning displacement derived from a normal distribution with {sigma} = 2 mm and {sigma} = 4 mm (standard deviation) for translational deviations and {sigma} = 1 deg for rotational deviations. The dose distributions of the 30 fractions were summed, resulting in the actual plan. The CTV dose coverage of the actual plans was compared with that of the static plans. Results: Random translational deviations of {sigma} = 2 mm and rotational deviations of {sigma} = 1 deg did not affect the CTV{sub primary} volume receiving 95% of the prescribed dose (V{sub 95}) regardless of the PTV margin used. A V{sub 95} reduction of 3% and 1% for a 0.0-mm and 1.5-mm PTV margin, respectively, was observed for {sigma} = 4 mm. The V{sub 95} of the CTV{sub elective} contralateral was approximately 1% and 5% lower than that of the static plan for {sigma} = 2 mm and {sigma} = 4 mm, respectively, and for PTV margins < 5.0 mm. An additional reduction of 1% was observed when rotational deviations were included. The same effect was observed for the CTV{sub elective} ipsilateral but with smaller dose differences than those for the contralateral side. The effect of the random uncertainties on the mean dose to the parotid glands was not significant. The maximal dose to the spinal cord increased by a maximum of 3 Gy. Conclusions: The margins to account for random setup uncertainties, in our clinical IMRT solution, should be 1.5 mm and 3.0 mm in the case of {sigma} = 2 mm and {sigma} = 4 mm, respectively, for the CTV{sub primary}. Larger margins (5.0 mm), however, should be applied to the CTV{sub elective}, if the goal of treatment is a V{sub 95} value of at least 99%.« less

  13. Health and loyalty promotion visits for new enrollees: results of a randomized controlled trial.

    PubMed

    Thompson, M; Gee, S; Larson, P; Kotz, K; Northrop, L

    2001-01-01

    Managed care needs effective and efficient ways to orient new members, enhance trust and loyalty, and offer prevention and self-care education and services. Recent adult enrollees of Kaiser Permanente (Northern California) were randomly assigned to one of three intervention conditions (n = 286) (individual visit with a physician, physician visit plus a visit with a health educator, a group visit of eight new members led by a physician and health educator) or a random control group (n = 278). Outcomes were gauged via pre- and post-visit questionnaires and a 20-min telephone survey at baseline and at a 6-month follow-up. Compared to controls, attendees of the three interventions had higher satisfaction, self-rated prevention knowledge, acceptance of health plan guidelines, and were more likely to plan to remain in the health plan. Group visit attendees stood out as experiencing the greatest benefits and were especially likely to report saving a telephone call or visit to their doctor by using a self-care handbook.

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

    Marutzky, Sam; Farnham, Irene

    The purpose of the Nevada National Security Site (NNSS) Integrated Sampling Plan (referred to herein as the Plan) is to provide a comprehensive, integrated approach for collecting and analyzing groundwater samples to meet the needs and objectives of the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) Underground Test Area (UGTA) Activity. Implementation of this Plan will provide high-quality data required by the UGTA Activity for ensuring public protection in an efficient and cost-effective manner. The Plan is designed to ensure compliance with the UGTA Quality Assurance Plan (QAP). The Plan’s scope comprises sample collectionmore » and analysis requirements relevant to assessing the extent of groundwater contamination from underground nuclear testing. This Plan identifies locations to be sampled by corrective action unit (CAU) and location type, sampling frequencies, sample collection methodologies, and the constituents to be analyzed. In addition, the Plan defines data collection criteria such as well-purging requirements, detection levels, and accuracy requirements; identifies reporting and data management requirements; and provides a process to ensure coordination between NNSS groundwater sampling programs for sampling of interest to UGTA. This Plan does not address compliance with requirements for wells that supply the NNSS public water system or wells involved in a permitted activity.« less

  15. Applying the theory of planned behavior to self-report dental attendance in Norwegian adults through structural equation modelling approach.

    PubMed

    Åstrøm, Anne N; Lie, Stein Atle; Gülcan, Ferda

    2018-05-31

    Understanding factors that affect dental attendance behavior helps in constructing effective oral health campaigns. A socio-cognitive model that adequately explains variance in regular dental attendance has yet to be validated among younger adults in Norway. Focusing a representative sample of younger Norwegian adults, this cross-sectional study provided an empirical test of the Theory of Planned Behavior (TPB) augmented with descriptive norm and action planning and estimated direct and indirect effects of attitudes, subjective norms, descriptive norms, perceived behavioral control and action planning on intended and self-reported regular dental attendance. Self-administered questionnaires provided by 2551, 25-35 year olds, randomly selected from the Norwegian national population registry were used to assess socio-demographic factors, dental attendance as well as the constructs of the augmented TPB model (attitudes, subjective norms, descriptive norms, intention, action planning). A two-stage process of structural equation modelling (SEM) was used to test the augmented TPB model. Confirmatory factor analysis, CFA, confirmed the proposed correlated 6-factor measurement model after re-specification. SEM revealed that attitudes, perceived behavioral control, subjective norms and descriptive norms explained intention. The corresponding standardized regression coefficients were respectively (β = 0.70), (β =0.18), (β = - 0.17) and (β =0.11) (p < 0.001). Intention (β =0.46) predicted action planning and action planning (β =0.19) predicted dental attendance behavior (p < 0.001). The model revealed indirect effects of intention and perceived behavioral control on behavior through action planning and through intention and action planning, respectively. The final model explained 64 and 41% of the total variance in intention and dental attendance behavior. The findings support the utility of the TPB, the expanded normative component and action planning in predicting younger adults' intended- and self-reported dental attendance. Interventions targeting young adults' dental attendance might usefully focus on positive consequences following this behavior accompanied with modeling and group performance.

  16. Chronic disease, functional health status, and demographics: a multi-dimensional approach to risk adjustment.

    PubMed Central

    Hornbrook, M C; Goodman, M J

    1996-01-01

    OBJECTIVE. The goal of this study was to develop unbiased risk-assessment models to be used for paying health plans on the basis of enrollee health status and use propensity. We explored the risk structure of adult employed HMO members using self-reported morbidities, functional status, perceived health status, and demographic characteristics. DATA SOURCES/STUDY SETTING. Data were collected on a random sample of members of a large, federally qualified, prepaid group practice, hospital-based HMO located in the Pacific Northwest. STUDY DESIGN. Multivariate linear nonparametric techniques were used to estimate risk weights on demographic, morbidity, and health status factors at the individual level. The dependent variable was annual real total health plan expense for covered services for the year following the survey. Repeated random split-sample validation techniques minimized outlier influences and avoided inappropriate distributional assumptions required by parametric techniques. DATA COLLECTION/EXTRACTION METHODS. A mail questionnaire containing an abbreviated medical history and the RAND-36 Health Survey was administered to a 5 percent sample of adult subscribers and their spouses in 1990 and 1991, with an overall 44 percent response rate. Utilization data were extracted from HMO automated information systems. Annual expenses were computed by weighting all utilization elements by standard unit costs for the HMO. PRINCIPAL FINDINGS. Prevalence of such major chronic diseases as heart disease, diabetes, depression, and asthma improve prediction of future medical expense; functional health status and morbidities are each better than simple demographic factors alone; functional and perceived health status as well as demographic characteristics and diagnoses together yield the best prediction performance and reduce opportunities for selection bias. We also found evidence of important interaction effects between functional/perceived health status scales and disease classes. CONCLUSIONS. Self-reported morbidities and functional health status are useful risk measures for adults. Risk-assessment research should focus on combining clinical information with social survey techniques to capitalize on the strengths of both approaches. Disease-specific functional health status scales should be developed and tested to capture the most information for prediction. PMID:8698586

  17. Impact of medicare part D plan features on use of generic drugs.

    PubMed

    Tang, Yan; Gellad, Walid F; Men, Aiju; Donohue, Julie M

    2014-06-01

    Little is known about how Medicare Part D plan features influence choice of generic versus brand drugs. To examine the association between Part D plan features and generic medication use. Data from a 2009 random sample of 1.6 million fee-for-service, Part D enrollees aged 65 years and above, who were not dually eligible or receiving low-income subsidies, were used to examine the association between plan features (generic cost-sharing, difference in brand and generic copay, prior authorization, step therapy) and choice of generic antidepressants, antidiabetics, and statins. Logistic regression models accounting for plan-level clustering were adjusted for sociodemographic and health status. Generic cost-sharing ranged from $0 to $9 for antidepressants and statins, and from $0 to $8 for antidiabetics (across 5th-95th percentiles). Brand-generic cost-sharing differences were smallest for statins (5th-95th percentiles: $16-$37) and largest for antidepressants ($16-$64) across plans. Beneficiaries with higher generic cost-sharing had lower generic use [adjusted odds ratio (OR)=0.97, 95% confidence interval (CI), 0.95-0.98 for antidepressants; OR=0.97, 95% CI, 0.96-0.98 for antidiabetics; OR=0.94, 95% CI, 0.92-0.95 for statins]. Larger brand-generic cost-sharing differences and prior authorization were significantly associated with greater generic use in all categories. Plans could increase generic use by 5-12 percentage points by reducing generic cost-sharing from the 75th ($7) to 25th percentiles ($4-$5), increasing brand-generic cost-sharing differences from the 25th ($25-$26) to 75th ($32-$33) percentiles, and using prior authorization and step therapy. Cost-sharing features and utilization management tools were significantly associated with generic use in 3 commonly used medication categories.

  18. Development and Validation of an Algorithm to Identify Planned Readmissions From Claims Data.

    PubMed

    Horwitz, Leora I; Grady, Jacqueline N; Cohen, Dorothy B; Lin, Zhenqiu; Volpe, Mark; Ngo, Chi K; Masica, Andrew L; Long, Theodore; Wang, Jessica; Keenan, Megan; Montague, Julia; Suter, Lisa G; Ross, Joseph S; Drye, Elizabeth E; Krumholz, Harlan M; Bernheim, Susannah M

    2015-10-01

    It is desirable not to include planned readmissions in readmission measures because they represent deliberate, scheduled care. To develop an algorithm to identify planned readmissions, describe its performance characteristics, and identify improvements. Consensus-driven algorithm development and chart review validation study at 7 acute-care hospitals in 2 health systems. For development, all discharges qualifying for the publicly reported hospital-wide readmission measure. For validation, all qualifying same-hospital readmissions that were characterized by the algorithm as planned, and a random sampling of same-hospital readmissions that were characterized as unplanned. We calculated weighted sensitivity and specificity, and positive and negative predictive values of the algorithm (version 2.1), compared to gold standard chart review. In consultation with 27 experts, we developed an algorithm that characterizes 7.8% of readmissions as planned. For validation we reviewed 634 readmissions. The weighted sensitivity of the algorithm was 45.1% overall, 50.9% in large teaching centers and 40.2% in smaller community hospitals. The weighted specificity was 95.9%, positive predictive value was 51.6%, and negative predictive value was 94.7%. We identified 4 minor changes to improve algorithm performance. The revised algorithm had a weighted sensitivity 49.8% (57.1% at large hospitals), weighted specificity 96.5%, positive predictive value 58.7%, and negative predictive value 94.5%. Positive predictive value was poor for the 2 most common potentially planned procedures: diagnostic cardiac catheterization (25%) and procedures involving cardiac devices (33%). An administrative claims-based algorithm to identify planned readmissions is feasible and can facilitate public reporting of primarily unplanned readmissions. © 2015 Society of Hospital Medicine.

  19. The Impact of Consumer-Directed Health Plans and Patient Socioeconomic Status on Physician Recommendations for Colorectal Cancer Screening

    PubMed Central

    Mallya, Giridhar; Polsky, Daniel

    2008-01-01

    Background Consumer-directed health plans are increasingly common, yet little is known about their impact on physician decision-making and preventive service use. Objective To determine how patients’ deductible levels and socioeconomic status may affect primary care physicians’ recommendations for colorectal cancer screening. Design, Setting, and Participants Screening recommendations were elicited using hypothetical vignettes from a national sample of 1,500 primary care physicians. Physicians were randomized to one of four vignettes describing a patient with either low or high socioeconomic status (SES) and either low- or high-deductible plan. Bivariate and multivariate analyses were used to examine how recommendations varied as a function of SES and deductible. Outcome Measures Rates of recommendation for home fecal occult blood testing, sigmoidoscopy, colonoscopy, and inappropriate screening, defined as no screening or office-based fecal occult blood testing. Results A total of 528 (49%) eligible physicians responded. Overall, 7.2% of physicians recommended inappropriate screening; 3.2% of patients with high SES in low-deductible plans received inappropriate screening recommendations and 11.4% of patients with low SES in high-deductible plans for an adjusted odds ratio of 0.22 (0.05–0.89). The odds of a colonoscopy recommendation were over ten times higher (AOR 11.46, 5.26–24.94) for patients with high SES in low-deductible plans compared to patients with low SES in high-deductible plans. Funds in medical savings accounts eliminated differences in inappropriate screening recommendations. Conclusions Patient SES and deductible-level affect physician recommendations for preventive care. Coverage of preventive services and funds in medical savings accounts may help to mitigate the impact of high-deductibles and SES on inappropriate recommendations. PMID:18629590

  20. Chain sampling plan (ChSP-1) for desired acceptable quality level (AQL) and limiting quality level (LQL)

    NASA Astrophysics Data System (ADS)

    Raju, C.; Vidya, R.

    2017-11-01

    Chain Sampling Plan is widely used whenever a small sample attributes plan is required to be used for situations involving destructive products coming out of continuous production process [1, 2]. This paper presents a procedure for the construction and selection of a ChSP-1 by attributes inspection based on membership functions [3]. A procedure using search technique is developed for obtaining the parameters of single sampling plan for a given set of AQL and LQL values. A sample of tables providing ChSP-1 plans for various combinations of AQL and LQL values are presented [4].

  1. Investigating the Randomness of Numbers

    ERIC Educational Resources Information Center

    Pendleton, Kenn L.

    2009-01-01

    The use of random numbers is pervasive in today's world. Random numbers have practical applications in such far-flung arenas as computer simulations, cryptography, gambling, the legal system, statistical sampling, and even the war on terrorism. Evaluating the randomness of extremely large samples is a complex, intricate process. However, the…

  2. Availability and Quality of Family Planning Services in the Democratic Republic of the Congo: High Potential for Improvement

    PubMed Central

    Mpunga, Dieudonné; Lumbayi, JP; Dikamba, Nelly; Mwembo, Albert; Ali Mapatano, Mala; Wembodinga, Gilbert

    2017-01-01

    Objective: To determine the availability and quality of family planning services within health facilities throughout the Democratic Republic of the Congo (DRC). Methods: Data were collected for the cross-sectional study from April 2014 to June 2014 by the Ministry of Public Health. A total of 1,568 health facilities that reported data to the National Health Information System were selected by multistage random sampling in the 11 provinces of the DRC existing at that time. Data were collected through interviews, document review, and direct observation. Two dependent variables were measured: availability of family planning services (consisting of a room for services, staff assigned to family planning, and evidence of client use of family planning) and quality of family planning services (assessed as “high” if the facility had at least 1 trained staff member, family planning service delivery guidelines, at least 3 types of methods, and a sphygmomanometer, or “low” if the facility did not meet any of these 4 criteria). Pearson's chi-square test and odds ratios (ORs) were used to test for significant associations, using the alpha significance level of .05. Results: We successfully surveyed 1,555 facilities (99.2%) of those included in the sample. One in every 3 facilities (33%) offered family planning services as assessed by the index of availability, of which 20% met all 4 criteria for providing high-quality services. Availability was greatest at the highest level of the health system (hospitals) and decreased incrementally with each health system level, with disparities between provinces and urban and rural areas. Facilities in urban areas were more likely than in rural areas to meet the standard for high-quality services (P<.001). Public facilities were less likely than private facilities to have high-quality services (P=.02). Among all 1,555 facilities surveyed, 14% had at least 3 types of methods available at the time of the survey; the most widely available methods were male condoms, combined oral contraceptive pills, and progestin-only injectable contraceptives. Conclusion: Availability and quality of family planning services in health facilities in the DRC remain low, with inequitable distribution of services throughout the country. To improve access to and use of family planning, efforts should focus on improving availability and quality at lower health system levels and in rural areas where the majority of the population lives. PMID:28588047

  3. Family planning utilization and factors associated among women receiving abortion services in health facilities of central zone towns of Tigray, Northern Ethiopia: a cross sectional Study.

    PubMed

    Hagos, Goshu; Tura, Gurmesa; Kahsay, Gizienesh; Haile, Kebede; Grum, Teklit; Araya, Tsige

    2018-06-05

    Abortion remains among the leading causes of maternal death worldwide. Post-abortion contraception is significantly effective in preventing unintended pregnancy and abortion if provided before women leave the health facilty. However, the status of post-abortion family planning (PAFP) utilization and the contributing factors are not well studied in Tigray region. So, we conduct study aimed on family planning utilization and factors associated with it among women receiving abortion services. A facility based cross-sectional study design was conducted among women receiving abortion services in central zone of Tigray from December 2015to February 2016 using a total of 416 sample size. Women who came for abortion services were selected using systematic random sampling technique.. The data were collected using a pre-tested interviewer administered questionnair. Data were coded and entered in to Epi info 7 and then exported to SPSS for analysis. Descriptive statisticslike frequencies and mean were computed to display the results. Both Bivariable and multivariable logistic regression was used in the analysis. Variables statistically significant at p < 0.05 in the bivariable analysis were checked in multivariable logistic regration to identify independently associated factors. Then variables which were significantly associated with post abortion family planning utilization at p-value < 0.05 in the multivariable analysis were declared as significantly associated factors. A total of 409 abortion clients were interviewed in this study with 98.3% of response rate. Majority 290 (70.9%) of study participants utilized contracepives after abortion. Type of health facility, the decision maker on timing of having child, knowledge that pregnancy can happen soon after abortion and husband's opposition towards contraceptives were significantly associated with Post-abortion family planning ustilization. About one-third of abortion women failed to receive contraceptive before leaving the facility. Private facilities should strengthen utilization of contraceptives on post abortion care service. Health providers should provide counseling on timing of fertility-return following abortion before women left the facility once they receive abortion care. Women empowerment through enhancing community's awareness focusing on own decision making in the family planning utilization including the partner should be strengthened.

  4. The Costs of Decedents in the Medicare Program: Implications for Payments to Medicare+Choice Plans

    PubMed Central

    Buntin, Melinda Beeuwkes; Garber, Alan M; McClellan, Mark; Newhouse, Joseph P

    2004-01-01

    Objective To discuss and quantify the incentives that Medicare managed care plans have to avoid (through selective enrollment or disenrollment) people who are at risk for very high costs, focusing on Medicare beneficiaries in the last year of life—a group that accounts for more than one-quarter of Medicare's annual expenditures. Data Source Medicare administrative claims for 1994 and 1995. Study Design We calculated the payment a plan would have received under three risk-adjustment systems for each beneficiary in our 1995 sample based on his or her age, gender, county of residence, original reason for Medicare entitlement, and principal inpatient diagnoses received during any hospital stays in 1994. We compared these amounts to the actual costs incurred by those beneficiaries. We then looked for clinical categories that were predictive of costs, including costs in a beneficiary's last year of life, not accounted for by the risk adjusters. Data Extraction Methods The analyses were conducted using claims for a 5 percent random sample of Medicare beneficiaries who died in 1995 and a matched group of survivors. Principal Findings Medicare is currently implementing the Principal Inpatient Diagnostic Cost Groups (PIP-DCG) risk adjustment payment system to address the problem of risk selection in the Medicare+Choice program. We quantify the strong financial disincentives to enroll terminally ill beneficiaries that plans still have under this risk adjustment system. We also show that up to one-third of the selection observed between Medicare HMOs and the traditional fee-for-service system could be due to differential enrollment of decedents. A risk adjustment system that incorporated more of the available diagnostic information would attenuate this disincentive; however, plans could still use clinical information (not included in the risk adjustment scheme) to identify beneficiaries whose expected costs exceed expected payments. Conclusions More disaggregated prospective risk adjustment methods and alternative payment systems that compensate plans for delivering care to certain classes of patients should be considered to ensure access to high-quality managed care for all beneficiaries. PMID:14965080

  5. Planning and problem-solving training for patients with schizophrenia: a randomized controlled trial

    PubMed Central

    2011-01-01

    Background The purpose of this study was to assess whether planning and problem-solving training is more effective in improving functional capacity in patients with schizophrenia than a training program addressing basic cognitive functions. Methods Eighty-nine patients with schizophrenia were randomly assigned either to a computer assisted training of planning and problem-solving or a training of basic cognition. Outcome variables included planning and problem-solving ability as well as functional capacity, which represents a proxy measure for functional outcome. Results Planning and problem-solving training improved one measure of planning and problem-solving more strongly than basic cognition training, while two other measures of planning did not show a differential effect. Participants in both groups improved over time in functional capacity. There was no differential effect of the interventions on functional capacity. Conclusion A differential effect of targeting specific cognitive functions on functional capacity could not be established. Small differences on cognitive outcome variables indicate a potential for differential effects. This will have to be addressed in further research including longer treatment programs and other settings. Trial registration ClinicalTrials.gov NCT00507988 PMID:21527028

  6. Reliability systems for implantable cardiac defibrillator batteries

    NASA Astrophysics Data System (ADS)

    Takeuchi, Esther S.

    The reliability of the power sources used in implantable cardiac defibrillators is critical due to the life-saving nature of the device. Achieving a high reliability power source depends on several systems functioning together. Appropriate cell design is the first step in assuring a reliable product. Qualification of critical components and of the cells using those components is done prior to their designation as implantable grade. Product consistency is assured by control of manufacturing practices and verified by sampling plans using both accelerated and real-time testing. Results to date show that lithium/silver vanadium oxide cells used for implantable cardiac defibrillators have a calculated maximum random failure rate of 0.005% per test month.

  7. Influence of Religion on Attitude Towards Suicide: An Indian Perspective.

    PubMed

    Thimmaiah, Rohini; Poreddi, Vijayalakshmi; Ramu, Rajalakshmi; Selvi, Sugavana; Math, Suresh Bada

    2016-12-01

    This cross-sectional survey was aimed to compare attitudes towards suicide and suicidal behaviour among randomly selected sample (N = 172) belonged to Hindu and Muslim religions. Data were collected through face-to-face interview. Hindus differed from Muslims regarding suicidal attempts among family (χ (2) = 12.356, p < .002) and community members (χ (2) = 20.425, p < .000). Our study also showed that suicidal behaviours were comparatively low among Muslim participants than Hindus. Further, Muslims hold more negative attitudes towards suicide than Hindus. An enhanced understanding of attitudes towards suicide among general population may be crucial to plan educational, intervention and prevention programs.

  8. Uncertainties in planned dose due to the limited voxel size of the planning CT when treating lung tumors with proton therapy

    NASA Astrophysics Data System (ADS)

    España, Samuel; Paganetti, Harald

    2011-07-01

    Dose calculation for lung tumors can be challenging due to the low density and the fine structure of the geometry. The latter is not fully considered in the CT image resolution used in treatment planning causing the prediction of a more homogeneous tissue distribution. In proton therapy, this could result in predicting an unrealistically sharp distal dose falloff, i.e. an underestimation of the distal dose falloff degradation. The goal of this work was the quantification of such effects. Two computational phantoms resembling a two-dimensional heterogeneous random lung geometry and a swine lung were considered applying a variety of voxel sizes for dose calculation. Monte Carlo simulations were used to compare the dose distributions predicted with the voxel size typically used for the treatment planning procedure with those expected to be delivered using the finest resolution. The results show, for example, distal falloff position differences of up to 4 mm between planned and expected dose at the 90% level for the heterogeneous random lung (assuming treatment plan on a 2 × 2 × 2.5 mm3 grid). For the swine lung, differences of up to 38 mm were seen when airways are present in the beam path when the treatment plan was done on a 0.8 × 0.8 × 2.4 mm3 grid. The two-dimensional heterogeneous random lung phantom apparently does not describe the impact of the geometry adequately because of the lack of heterogeneities in the axial direction. The differences observed in the swine lung between planned and expected dose are presumably due to the poor axial resolution of the CT images used in clinical routine. In conclusion, when assigning margins for treatment planning for lung cancer, proton range uncertainties due to the heterogeneous lung geometry and CT image resolution need to be considered.

  9. RECAL: A Computer Program for Selecting Sample Days for Recreation Use Estimation

    Treesearch

    D.L. Erickson; C.J. Liu; H. Ken Cordell; W.L. Chen

    1980-01-01

    Recreation Calendar (RECAL) is a computer program in PL/I for drawing a sample of days for estimating recreation use. With RECAL, a sampling period of any length may be chosen; simple random, stratified random, and factorial designs can be accommodated. The program randomly allocates days to strata and locations.

  10. 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…

  11. Implementation and acceptability of strategies instituted for engaging men in family planning services in Kibaha district, Tanzania.

    PubMed

    Msovela, Judith; Tengia-Kessy, Anna

    2016-11-21

    Men as the main decision makers in most of African families have an important role to play towards acceptance of family planning methods. This study sought to identify strategies used to engage men in family planning services and determine the extent to which men in Kibaha district in Tanzania accept these interventions. We conducted a cross sectional study using both quantitative and qualitative techniques. We used a questionnaire to interview a random sample of 365 of currently married or cohabiting men who had at least one child under the age of five years. We further conducted in-depth interviews with health workers involved in delivering reproductive health services as well as community dispensers of family planning commodities. Descriptive analysis was used to determine the extent to which men were engaged in family planning services. The data from the indepth interviews were analysed manually according to the predetermined themes, guided by the grounded theory to identify the existing strategies used to encourage male involvement in family planning services. According to the key informants, strategies that are used to encourage men to engage in family planning services include invitations through their spouses, either verbally or by using partner notification cards, incorporating family planning messages during monthly meetings and community outreach reproductive health programs. Of 365 men responding to the questionnaire, only 31 (8.4%) said they were invited to accompany their spouses to family planning clinics. Among them, 71% (22/31) visited family planning clinics. A third (32%) of the respondents had heard of community health meetings and only 20.7% of them attended these meetings. More than a third (12/34) of men who attended these meeting asserted that family planning messages targeting men featured in the agenda and subsequently half of them visited health facilities for family planning services. Existing strategies such as invitations to clinics and community sensitization have shown to encourage men to engage in family planning services. However, these interventions reach few men and hence there is a need to rolling them up to improve uptake of family planning services.

  12. Understanding and comparisons of different sampling approaches for the Fourier Amplitudes Sensitivity Test (FAST)

    PubMed Central

    Xu, Chonggang; Gertner, George

    2013-01-01

    Fourier Amplitude Sensitivity Test (FAST) is one of the most popular uncertainty and sensitivity analysis techniques. It uses a periodic sampling approach and a Fourier transformation to decompose the variance of a model output into partial variances contributed by different model parameters. Until now, the FAST analysis is mainly confined to the estimation of partial variances contributed by the main effects of model parameters, but does not allow for those contributed by specific interactions among parameters. In this paper, we theoretically show that FAST analysis can be used to estimate partial variances contributed by both main effects and interaction effects of model parameters using different sampling approaches (i.e., traditional search-curve based sampling, simple random sampling and random balance design sampling). We also analytically calculate the potential errors and biases in the estimation of partial variances. Hypothesis tests are constructed to reduce the effect of sampling errors on the estimation of partial variances. Our results show that compared to simple random sampling and random balance design sampling, sensitivity indices (ratios of partial variances to variance of a specific model output) estimated by search-curve based sampling generally have higher precision but larger underestimations. Compared to simple random sampling, random balance design sampling generally provides higher estimation precision for partial variances contributed by the main effects of parameters. The theoretical derivation of partial variances contributed by higher-order interactions and the calculation of their corresponding estimation errors in different sampling schemes can help us better understand the FAST method and provide a fundamental basis for FAST applications and further improvements. PMID:24143037

  13. Understanding and comparisons of different sampling approaches for the Fourier Amplitudes Sensitivity Test (FAST).

    PubMed

    Xu, Chonggang; Gertner, George

    2011-01-01

    Fourier Amplitude Sensitivity Test (FAST) is one of the most popular uncertainty and sensitivity analysis techniques. It uses a periodic sampling approach and a Fourier transformation to decompose the variance of a model output into partial variances contributed by different model parameters. Until now, the FAST analysis is mainly confined to the estimation of partial variances contributed by the main effects of model parameters, but does not allow for those contributed by specific interactions among parameters. In this paper, we theoretically show that FAST analysis can be used to estimate partial variances contributed by both main effects and interaction effects of model parameters using different sampling approaches (i.e., traditional search-curve based sampling, simple random sampling and random balance design sampling). We also analytically calculate the potential errors and biases in the estimation of partial variances. Hypothesis tests are constructed to reduce the effect of sampling errors on the estimation of partial variances. Our results show that compared to simple random sampling and random balance design sampling, sensitivity indices (ratios of partial variances to variance of a specific model output) estimated by search-curve based sampling generally have higher precision but larger underestimations. Compared to simple random sampling, random balance design sampling generally provides higher estimation precision for partial variances contributed by the main effects of parameters. The theoretical derivation of partial variances contributed by higher-order interactions and the calculation of their corresponding estimation errors in different sampling schemes can help us better understand the FAST method and provide a fundamental basis for FAST applications and further improvements.

  14. Why natural disaster planning scenarios are often so disastrously wrong.

    NASA Astrophysics Data System (ADS)

    Verosub, K. L.

    2017-12-01

    Taken together the four hurricanes that impacted the United States in the summer of 2017 demonstrate the difficulties involved in trying to plan for any natural disaster, not simply a major hurricane. They also highlight the extraordinary degree to which small and/or random variations in initial conditions can have enormous consequences on the outcome of an event and on the ability of a society to respond to it. For example, if Harvey had been moving faster, it would have meant less rainfall and hence less flooding in the Houston area whereas a slight change in the path of Irma would have significantly affected which portions of the Florida peninsula would have experienced greater or lesser devastation. In the case of Marie, hurricane intensity and path as well as the terrain in Puerto Rico and the inherent state of its infrastructure greatly complicated relief and recovery efforts there. An additional factor that makes planning scenarios so difficult to develop is that major natural disasters can often be analyzed as a sequence of events. At each juncture in the sequence, the event might evolve along two or more very different pathways, which can lead to different outcomes. Sometimes, as with Nate, an event evolves more or less "as expected" and the planning scenario does what it was supposed to do, namely, help people respond to the event. But to a much greater extent than is usually recognized, small or random variations can drive an event off its expected trajectory and into a response realm that "no one could have foreseen." Even worse is when those small or random variations allow an event to bifurcate and follow two or more different pathways simultaneously, leading to a cascading disaster that totally overwhelms whatever planning and preparation has been put in place. Perhaps the main lessons to be learned from these storms is that planning for any disaster requires greater recognition of the importance of small or random factors and greater appreciation of the complexity of these events. One plan or one model scenario does not provide adequate preparation for all events of a particular type and is probably unlikely to provide adequate preparation for any single given event.

  15. 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.

  16. Spatial distribution and sequential sampling plans for Tuta absoluta (Lepidoptera: Gelechiidae) in greenhouse tomato crops.

    PubMed

    Cocco, Arturo; Serra, Giuseppe; Lentini, Andrea; Deliperi, Salvatore; Delrio, Gavino

    2015-09-01

    The within- and between-plant distribution of the tomato leafminer, Tuta absoluta (Meyrick), was investigated in order to define action thresholds based on leaf infestation and to propose enumerative and binomial sequential sampling plans for pest management applications in protected crops. The pest spatial distribution was aggregated between plants, and median leaves were the most suitable sample to evaluate the pest density. Action thresholds of 36 and 48%, 43 and 56% and 60 and 73% infested leaves, corresponding to economic thresholds of 1 and 3% damaged fruits, were defined for tomato cultivars with big, medium and small fruits respectively. Green's method was a more suitable enumerative sampling plan as it required a lower sampling effort. Binomial sampling plans needed lower average sample sizes than enumerative plans to make a treatment decision, with probabilities of error of <0.10. The enumerative sampling plan required 87 or 343 leaves to estimate the population density in extensive or intensive ecological studies respectively. Binomial plans would be more practical and efficient for control purposes, needing average sample sizes of 17, 20 and 14 leaves to take a pest management decision in order to avoid fruit damage higher than 1% in cultivars with big, medium and small fruits respectively. © 2014 Society of Chemical Industry.

  17. Methods for sample size determination in cluster randomized trials

    PubMed Central

    Rutterford, Clare; Copas, Andrew; Eldridge, Sandra

    2015-01-01

    Background: The use of cluster randomized trials (CRTs) is increasing, along with the variety in their design and analysis. The simplest approach for their sample size calculation is to calculate the sample size assuming individual randomization and inflate this by a design effect to account for randomization by cluster. The assumptions of a simple design effect may not always be met; alternative or more complicated approaches are required. Methods: We summarise a wide range of sample size methods available for cluster randomized trials. For those familiar with sample size calculations for individually randomized trials but with less experience in the clustered case, this manuscript provides formulae for a wide range of scenarios with associated explanation and recommendations. For those with more experience, comprehensive summaries are provided that allow quick identification of methods for a given design, outcome and analysis method. Results: We present first those methods applicable to the simplest two-arm, parallel group, completely randomized design followed by methods that incorporate deviations from this design such as: variability in cluster sizes; attrition; non-compliance; or the inclusion of baseline covariates or repeated measures. The paper concludes with methods for alternative designs. Conclusions: There is a large amount of methodology available for sample size calculations in CRTs. This paper gives the most comprehensive description of published methodology for sample size calculation and provides an important resource for those designing these trials. PMID:26174515

  18. Testing novel patient financial incentives to increase breast cancer screening.

    PubMed

    Merrick, Elizabeth Levy; Hodgkin, Dominic; Horgan, Constance M; Lorenz, Laura S; Panas, Lee; Ritter, Grant A; Kasuba, Paul; Poskanzer, Debra; Nefussy, Renee Altman

    2015-11-01

    To examine the effects of 3 types of low-cost financial incentives for patients, including a novel "person-centered" approach on breast cancer screening (mammogram) rates. Randomized controlled trial with 4 arms: 3 types of financial incentives ($15 gift card, entry into lottery for $250 gift card, and a person-centered incentive with choice of $15 gift card or lottery) and a control group. Sample included privately insured Tufts Health Plan members in Massachusetts who were women aged 42 to 69 years with no mammogram claim in ≥ 2.6 years. A sample of 4700 eligible members were randomized to 4 study arms. The control group received a standard reminder letter and the incentive groups received a reminder letter plus an incentive offer for obtaining a mammogram within the next 4 months. Bivariate tests and multivariate logistic regression were used to assess the incentives' impact on mammogram receipt. Data were analyzed for 4427 members (after exclusions such as undeliverable mail). The percent of members receiving a mammogram during the study was 11.7% (gift card), 12.1% (lottery), 13.4% (person-centered/choice), and 11.9% (controls). Differences were not statistically significant in bivariate or multivariate full-sample analyses. In exploratory subgroup analyses of members with a mammogram during the most recent year prior to the study-defined gap, person-centered incentives were associated with a higher likelihood of mammogram receipt. None of the low-cost incentives tested had a statistically significant effect on mammogram rates in the full sample. Exploratory findings for members who were more recently screened suggest that they may be more responsive to person-centered incentives.

  19. Outpatient Dermatological Diagnoses in Spain: Results From the National DIADERM Random Sampling Project.

    PubMed

    Buendía-Eisman, A; Arias-Santiago, S; Molina-Leyva, A; Gilaberte, Y; Fernández-Crehuet, P; Husein-ElAhmed, H; Viera-Ramírez, A; Fernández-Peñas, P; Taberner, R; Descalzo, M Á; García-Doval, I

    2018-06-01

    Dermatologists perform most of their work in outpatient or private clinics. Data on the diagnoses made by dermatologists in these settings are lacking, however, as outpatient activity, unlike hospital activity, is difficult to code. The aim of this study was to analyze the diagnoses made by members of the Spanish Academy of Dermatology and Venereology (AEDV) at dermatology clinics in Spain. We selected a random sample of AEDV dermatologists drawn from the AEDV list and stratified by geographic area. The selected dermatologists received instructions on how to collect the data required. Each participant recorded the diagnosis reached and other data for patients seen during 2 specified periods: 3 days in January and 3 days in May. The diagnoses were subsequently coded by a dermatologist expert in applying the International Classification of Diseases (10th revision). In view of the complex nature of the sample, data were analyzed with standard error and finite population corrections. The sample consisted of 124 dermatologists. Of these, 65% participated in the first phase of the study and 59% in the second. An estimated 621 562 patients (95% CI, 368 130-874 995) visit the dermatologist every month in Spain. This is the equivalent of 28 (25-31) patients per day per clinic. The most common diagnosis recorded was actinic keratosis, followed by basal cell carcinoma and melanocytic nevus. The vast majority of visits took place at the clinic, but 1% of patients (0.3%-3%) were assessed using teledermatology. This is the first study in Spain to analyze diagnoses made by AEDV members at outpatient dermatology clinics. Our findings show a high volume of activity and will be useful for guiding health care planning, resource use, and future studies. Copyright © 2018. Publicado por Elsevier España, S.L.U.

  20. Design and operation of the National Survey of Children with Special Health Care Needs, 2009-2010.

    PubMed

    Bramlett, Matthew D; Blumberg, Stephen J; Ormson, A Elizabeth; George, Jacquelyn M; Williams, Kim L; Frasier, Alicia M; Skalland, Benjamin J; Santos, Kathleen B; Vsetecka, Danielle M; Morrison, Heather M; Pedlow, Steven; Wang, Fang

    2014-11-01

    This report presents the development, plan, and operation of the 2009-2010 National Survey of Children with Special Health Care Needs, a module of the State and Local Area Integrated Telephone Survey. The survey is conducted by the Centers for Disease Control and Prevention's National Center for Health Statistics. This survey was designed to produce national and state-specific prevalence estimates of children with special health care needs (CSHCN), to describe the types of services that they need and use, and to assess aspects of the system of care for CSHCN. A random-digit-dial sample of households with children under age 18 years was constructed for each of the 50 states and the District of Columbia. The sampling frame consisted of landline phone numbers and cellular(cell) phone numbers of households that reported a cell-phone-only or cell-phone-mainly status. Children in identified households were screened for special health care needs. If CSHCN were identified in the household, a detailed interview was conducted for one randomly selected child with special health care needs. Respondents were parents or guardians who knew about the children's health and health care. A total of 196,159 household screening interviews were completed from July 2009 through March 2011, resulting in 40,242 completed special-needs interviews, including 2,991 from cell-phone interviews. The weighted overall response rate was 43.7% for the landline sample, 15.2% for the cell-phone sample, and 25.5% overall. All material appearing in this report is in the public domain and may be reproduced or copied without permission; citation as to source, however, is appreciated.

  1. Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites

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

    None

    2012-10-24

    This plan incorporates U.S. Department of Energy (DOE) Office of Legacy Management (LM) standard operating procedures (SOPs) into environmental monitoring activities and will be implemented at all sites managed by LM. This document provides detailed procedures for the field sampling teams so that samples are collected in a consistent and technically defensible manner. Site-specific plans (e.g., long-term surveillance and maintenance plans, environmental monitoring plans) document background information and establish the basis for sampling and monitoring activities. Information will be included in site-specific tabbed sections to this plan, which identify sample locations, sample frequencies, types of samples, field measurements, and associatedmore » analytes for each site. Additionally, within each tabbed section, program directives will be included, when developed, to establish additional site-specific requirements to modify or clarify requirements in this plan as they apply to the corresponding site. A flowchart detailing project tasks required to accomplish routine sampling is displayed in Figure 1. LM environmental procedures are contained in the Environmental Procedures Catalog (LMS/PRO/S04325), which incorporates American Society for Testing and Materials (ASTM), DOE, and U.S. Environmental Protection Agency (EPA) guidance. Specific procedures used for groundwater and surface water monitoring are included in Appendix A. If other environmental media are monitored, SOPs used for air, soil/sediment, and biota monitoring can be found in the site-specific tabbed sections in Appendix D or in site-specific documents. The procedures in the Environmental Procedures Catalog are intended as general guidance and require additional detail from planning documents in order to be complete; the following sections fulfill that function and specify additional procedural requirements to form SOPs. Routine revision of this Sampling and Analysis Plan will be conducted annually at the beginning of each fiscal year when attachments in Appendix D, including program directives and sampling location/analytical tables, will be reviewed by project personnel and updated. The sampling location/analytical tables in Appendix D, however, may have interim updates according to project direction that are not reflected in this plan. Deviations from location/analytical tables in Appendix D prior to sampling will be documented in project correspondence (e.g., startup letters). If significant changes to other aspects of this plan are required before the annual update, then the plan will be revised as needed.« less

  2. 40 CFR 265.92 - Sampling and analysis.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Sampling and analysis. 265.92 Section... FACILITIES Ground-Water Monitoring § 265.92 Sampling and analysis. (a) The owner or operator must obtain and... follow a ground-water sampling and analysis plan. He must keep this plan at the facility. The plan must...

  3. 40 CFR 265.92 - Sampling and analysis.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Sampling and analysis. 265.92 Section... FACILITIES Ground-Water Monitoring § 265.92 Sampling and analysis. (a) The owner or operator must obtain and... follow a ground-water sampling and analysis plan. He must keep this plan at the facility. The plan must...

  4. CONCEPTT: Continuous Glucose Monitoring in Women with Type 1 Diabetes in Pregnancy Trial: A multi-center, multi-national, randomized controlled trial - Study protocol.

    PubMed

    Feig, Denice S; Asztalos, Elizabeth; Corcoy, Rosa; De Leiva, Alberto; Donovan, Lois; Hod, Moshe; Jovanovic, Lois; Keely, Erin; Kollman, Craig; McManus, Ruth; Murphy, Kellie; Ruedy, Katrina; Sanchez, J Johanna; Tomlinson, George; Murphy, Helen R

    2016-07-18

    Women with type 1 diabetes strive for optimal glycemic control before and during pregnancy to avoid adverse obstetric and perinatal outcomes. For most women, optimal glycemic control is challenging to achieve and maintain. The aim of this study is to determine whether the use of real-time continuous glucose monitoring (RT-CGM) will improve glycemic control in women with type 1 diabetes who are pregnant or planning pregnancy. A multi-center, open label, randomized, controlled trial of women with type 1 diabetes who are either planning pregnancy with an HbA1c of 7.0 % to ≤10.0 % (53 to ≤ 86 mmol/mol) or are in early pregnancy (<13 weeks 6 days) with an HbA1c of 6.5 % to ≤10.0 % (48 to ≤ 86 mmol/mol). Participants will be randomized to either RT-CGM alongside conventional intermittent home glucose monitoring (HGM), or HGM alone. Eligible women will wear a CGM which does not display the glucose result for 6 days during the run-in phase. To be eligible for randomization, a minimum of 4 HGM measurements per day and a minimum of 96 hours total with 24 hours overnight (11 pm-7 am) of CGM glucose values are required. Those meeting these criteria are randomized to RT- CGM or HGM. A total of 324 women will be recruited (110 planning pregnancy, 214 pregnant). This takes into account 15 and 20 % attrition rates for the planning pregnancy and pregnant cohorts and will detect a clinically relevant 0.5 % difference between groups at 90 % power with 5 % significance. Randomization will stratify for type of insulin treatment (pump or multiple daily injections) and baseline HbA1c. Analyses will be performed according to intention to treat. The primary outcome is the change in glycemic control as measured by HbA1c from baseline to 24 weeks or conception in women planning pregnancy, and from baseline to 34 weeks gestation during pregnancy. Secondary outcomes include maternal hypoglycemia, CGM time in, above and below target (3.5-7.8 mmol/l), glucose variability measures, maternal and neonatal outcomes. This will be the first international multicenter randomized controlled trial to evaluate the impact of RT- CGM before and during pregnancy in women with type 1 diabetes. ClinicalTrials.gov Identifier: NCT01788527 Registration Date: December 19, 2012.

  5. Central Fetal Monitoring With and Without Computer Analysis: A Randomized Controlled Trial.

    PubMed

    Nunes, Inês; Ayres-de-Campos, Diogo; Ugwumadu, Austin; Amin, Pina; Banfield, Philip; Nicoll, Antony; Cunningham, Simon; Sousa, Paulo; Costa-Santos, Cristina; Bernardes, João

    2017-01-01

    To evaluate whether intrapartum fetal monitoring with computer analysis and real-time alerts decreases the rate of newborn metabolic acidosis or obstetric intervention when compared with visual analysis. A randomized clinical trial carried out in five hospitals in the United Kingdom evaluated women with singleton, vertex fetuses of 36 weeks of gestation or greater during labor. Continuous central fetal monitoring by computer analysis and online alerts (experimental arm) was compared with visual analysis (control arm). Fetal blood sampling and electrocardiographic ST waveform analysis were available in both arms. The primary outcome was incidence of newborn metabolic acidosis (pH less than 7.05 and base deficit greater than 12 mmol/L). Prespecified secondary outcomes included operative delivery, use of fetal blood sampling, low 5-minute Apgar score, neonatal intensive care unit admission, hypoxic-ischemic encephalopathy, and perinatal death. A sample size of 3,660 per group (N=7,320) was planned to be able to detect a reduction in the rate of metabolic acidosis from 2.8% to 1.8% (two-tailed α of 0.05 with 80% power). From August 2011 through July 2014, 32,306 women were assessed for eligibility and 7,730 were randomized: 3,961 to computer analysis and online alerts, and 3,769 to visual analysis. Baseline characteristics were similar in both groups. Metabolic acidosis occurred in 16 participants (0.40%) in the experimental arm and 22 participants (0.58%) in the control arm (relative risk 0.69 [0.36-1.31]). No statistically significant differences were found in the incidence of secondary outcomes. Compared with visual analysis, computer analysis of fetal monitoring signals with real-time alerts did not significantly reduce the rate of metabolic acidosis or obstetric intervention. A lower-than-expected rate of newborn metabolic acidosis was observed in both arms of the trial. ISRCTN Registry, http://www.isrctn.com, ISRCTN42314164.

  6. Influences of sampling size and pattern on the uncertainty of correlation estimation between soil water content and its influencing factors

    NASA Astrophysics Data System (ADS)

    Lai, Xiaoming; Zhu, Qing; Zhou, Zhiwen; Liao, Kaihua

    2017-12-01

    In this study, seven random combination sampling strategies were applied to investigate the uncertainties in estimating the hillslope mean soil water content (SWC) and correlation coefficients between the SWC and soil/terrain properties on a tea + bamboo hillslope. One of the sampling strategies is the global random sampling and the other six are the stratified random sampling on the top, middle, toe, top + mid, top + toe and mid + toe slope positions. When each sampling strategy was applied, sample sizes were gradually reduced and each sampling size contained 3000 replicates. Under each sampling size of each sampling strategy, the relative errors (REs) and coefficients of variation (CVs) of the estimated hillslope mean SWC and correlation coefficients between the SWC and soil/terrain properties were calculated to quantify the accuracy and uncertainty. The results showed that the uncertainty of the estimations decreased as the sampling size increasing. However, larger sample sizes were required to reduce the uncertainty in correlation coefficient estimation than in hillslope mean SWC estimation. Under global random sampling, 12 randomly sampled sites on this hillslope were adequate to estimate the hillslope mean SWC with RE and CV ≤10%. However, at least 72 randomly sampled sites were needed to ensure the estimated correlation coefficients with REs and CVs ≤10%. Comparing with all sampling strategies, reducing sampling sites on the middle slope had the least influence on the estimation of hillslope mean SWC and correlation coefficients. Under this strategy, 60 sites (10 on the middle slope and 50 on the top and toe slopes) were enough to ensure the estimated correlation coefficients with REs and CVs ≤10%. This suggested that when designing the SWC sampling, the proportion of sites on the middle slope can be reduced to 16.7% of the total number of sites. Findings of this study will be useful for the optimal SWC sampling design.

  7. Sequential time interleaved random equivalent sampling for repetitive signal.

    PubMed

    Zhao, Yijiu; Liu, Jingjing

    2016-12-01

    Compressed sensing (CS) based sampling techniques exhibit many advantages over other existing approaches for sparse signal spectrum sensing; they are also incorporated into non-uniform sampling signal reconstruction to improve the efficiency, such as random equivalent sampling (RES). However, in CS based RES, only one sample of each acquisition is considered in the signal reconstruction stage, and it will result in more acquisition runs and longer sampling time. In this paper, a sampling sequence is taken in each RES acquisition run, and the corresponding block measurement matrix is constructed using a Whittaker-Shannon interpolation formula. All the block matrices are combined into an equivalent measurement matrix with respect to all sampling sequences. We implemented the proposed approach with a multi-cores analog-to-digital converter (ADC), whose ADC cores are time interleaved. A prototype realization of this proposed CS based sequential random equivalent sampling method has been developed. It is able to capture an analog waveform at an equivalent sampling rate of 40 GHz while sampled at 1 GHz physically. Experiments indicate that, for a sparse signal, the proposed CS based sequential random equivalent sampling exhibits high efficiency.

  8. ICP Corporate Customer Assessment - Sampling Plan

    DTIC Science & Technology

    1995-07-01

    CORPORATE CUSTOMER ASSESSMENT - SAMPLING PLAN JULY 1995 Lead Analyst: Lieutenant Commander William J. Wilkinson, USN Associate Analyst: Mr. Henry J...project developed a plan for conducting recurring surveys of Defense Logistics Agency customers , in support of the DLA Corporate Customer Assessment...Team. The primary product was a sampling plan, including stratification of customers by Military Service or Federal Agency and by commodity purchased

  9. 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.

  10. Designing a monitoring program to estimate estuarine survival of anadromous salmon smolts: simulating the effect of sample design on inference

    USGS Publications Warehouse

    Romer, Jeremy D.; Gitelman, Alix I.; Clements, Shaun; Schreck, Carl B.

    2015-01-01

    A number of researchers have attempted to estimate salmonid smolt survival during outmigration through an estuary. However, it is currently unclear how the design of such studies influences the accuracy and precision of survival estimates. In this simulation study we consider four patterns of smolt survival probability in the estuary, and test the performance of several different sampling strategies for estimating estuarine survival assuming perfect detection. The four survival probability patterns each incorporate a systematic component (constant, linearly increasing, increasing and then decreasing, and two pulses) and a random component to reflect daily fluctuations in survival probability. Generally, spreading sampling effort (tagging) across the season resulted in more accurate estimates of survival. All sampling designs in this simulation tended to under-estimate the variation in the survival estimates because seasonal and daily variation in survival probability are not incorporated in the estimation procedure. This under-estimation results in poorer performance of estimates from larger samples. Thus, tagging more fish may not result in better estimates of survival if important components of variation are not accounted for. The results of our simulation incorporate survival probabilities and run distribution data from previous studies to help illustrate the tradeoffs among sampling strategies in terms of the number of tags needed and distribution of tagging effort. This information will assist researchers in developing improved monitoring programs and encourage discussion regarding issues that should be addressed prior to implementation of any telemetry-based monitoring plan. We believe implementation of an effective estuary survival monitoring program will strengthen the robustness of life cycle models used in recovery plans by providing missing data on where and how much mortality occurs in the riverine and estuarine portions of smolt migration. These data could result in better informed management decisions and assist in guidance for more effective estuarine restoration projects.

  11. Hierarchical Motion Planning for Autonomous Aerial and Terrestrial Vehicles

    NASA Astrophysics Data System (ADS)

    Cowlagi, Raghvendra V.

    Autonomous mobile robots---both aerial and terrestrial vehicles---have gained immense importance due to the broad spectrum of their potential military and civilian applications. One of the indispensable requirements for the autonomy of a mobile vehicle is the vehicle's capability of planning and executing its motion, that is, finding appropriate control inputs for the vehicle such that the resulting vehicle motion satisfies the requirements of the vehicular task. The motion planning and control problem is inherently complex because it involves two disparate sub-problems: (1) satisfaction of the vehicular task requirements, which requires tools from combinatorics and/or formal methods, and (2) design of the vehicle control laws, which requires tools from dynamical systems and control theory. Accordingly, this problem is usually decomposed and solved over two levels of hierarchy. The higher level, called the geometric path planning level, finds a geometric path that satisfies the vehicular task requirements, e.g., obstacle avoidance. The lower level, called the trajectory planning level, involves sufficient smoothening of this geometric path followed by a suitable time parametrization to obtain a reference trajectory for the vehicle. Although simple and efficient, such hierarchical decomposition suffers a serious drawback: the geometric path planner has no information of the kinematical and dynamical constraints of the vehicle. Consequently, the geometric planner may produce paths that the trajectory planner cannot transform into a feasible reference trajectory. Two main ideas appear in the literature to remedy this problem: (a) randomized sampling-based planning, which eliminates the geometric planner altogether by planning in the vehicle state space, and (b) geometric planning supported by feedback control laws. The former class of methods suffer from a lack of optimality of the resultant trajectory, while the latter class of methods makes a restrictive assumption concerning the vehicle kinematical model. We propose a hierarchical motion planning framework based on a novel mode of interaction between these two levels of planning. This interaction rests on the solution of a special shortest-path problem on graphs, namely, one using costs defined on multiple edge transitions in the path instead of the usual single edge transition costs. These costs are provided by a local trajectory generation algorithm, which we implement using model predictive control and the concept of effective target sets for simplifying the non-convex constraints involved in the problem. The proposed motion planner ensures "consistency" between the two levels of planning, i.e., a guarantee that the higher level geometric path is always associated with a kinematically and dynamically feasible trajectory. The main contributions of this thesis are: 1. A motion planning framework based on history-dependent costs (H-costs) in cell decomposition graphs for incorporating vehicle dynamical constraints: this framework offers distinct advantages in comparison with the competing approaches of discretization of the state space, of randomized sampling-based motion planning, and of local feedback-based, decoupled hierarchical motion planning, 2. An efficient and flexible algorithm for finding optimal H-cost paths, 3. A precise and general formulation of a local trajectory problem (the tile motion planning problem) that allows independent development of the discrete planner and the trajectory planner, while maintaining "compatibility" between the two planners, 4. A local trajectory generation algorithm using mpc, and the application of the concept of effective target sets for a significant simplification of the local trajectory generation problem, 5. The geometric analysis of curvature-bounded traversal of rectangular channels, leading to less conservative results in comparison with a result reported in the literature, and also to the efficient construction of effective target sets for the solution of the tile motion planning problem, 6. A wavelet-based multi-resolution path planning scheme, and a proof of completeness of the proposed scheme: such proofs are altogether absent from other works on multi-resolution path planning, 7. A technique for extracting all information about cells---namely, the locations, the sizes, and the associated image intensities---directly from the set of significant detail coefficients considered for path planning at a given iteration, and 8. The extension of the multi-resolution path planning scheme to include vehicle dynamical constraints using the aforementioned history-dependent costs approach. The future work includes an implementation of the proposed framework involving a discrete planner that solves classical planning problems more general than the single-query path planning problem considered thus far, and involving trajectory generation schemes for realistic vehicle dynamical models such as the bicycle model.

  12. Random bit generation at tunable rates using a chaotic semiconductor laser under distributed feedback.

    PubMed

    Li, Xiao-Zhou; Li, Song-Sui; Zhuang, Jun-Ping; Chan, Sze-Chun

    2015-09-01

    A semiconductor laser with distributed feedback from a fiber Bragg grating (FBG) is investigated for random bit generation (RBG). The feedback perturbs the laser to emit chaotically with the intensity being sampled periodically. The samples are then converted into random bits by a simple postprocessing of self-differencing and selecting bits. Unlike a conventional mirror that provides localized feedback, the FBG provides distributed feedback which effectively suppresses the information of the round-trip feedback delay time. Randomness is ensured even when the sampling period is commensurate with the feedback delay between the laser and the grating. Consequently, in RBG, the FBG feedback enables continuous tuning of the output bit rate, reduces the minimum sampling period, and increases the number of bits selected per sample. RBG is experimentally investigated at a sampling period continuously tunable from over 16 ns down to 50 ps, while the feedback delay is fixed at 7.7 ns. By selecting 5 least-significant bits per sample, output bit rates from 0.3 to 100 Gbps are achieved with randomness examined by the National Institute of Standards and Technology test suite.

  13. Reducing medical service utilization by encouraging vaccines: randomized controlled trial.

    PubMed

    Berg, Gregory D; Thomas, Eileen; Silverstein, Steven; Neel, Cheryl L; Mireles, Matthew

    2004-11-01

    Vaccination against influenza is associated with reductions in hospitalizations for heart disease, cerebrovascular disease, pneumonia, or influenza, and the risk of death from all causes during the influenza season. Randomized controlled trial. All members enrolled in the Blue Cross Blue Shield Association's Government Wide Service Benefit Program in the states of Oklahoma, Rhode Island, Kentucky, California, Arizona, Utah, and Colorado in October 2002. The sample size was 339,220 members. Two identical influenza/pneumonia direct mail marketing pieces that encouraged members to receive influenza and pneumococcal vaccinations. The study period was October 15, 2002 through March 15, 2003 when most influenza cases occur. Data were collected in July 2003 and analyzed during August 2003. Administrative claims based on influenza/pneumonia inpatient admissions and emergency department (ED) visits. The intervention group experienced a 2.62% (p=0.010) higher rate of influenza vaccinations; 4.61% (p=0.080) higher rate of pneumonia vaccinations; 9.67% (p=0.136) lower rate of influenza/pneumonia inpatient admissions; and 22.64% (p=0.002) lower rate of influenza/pneumonia ED visits compared to the control group. The benefit-cost ratio (return on investment) from this intervention was estimated to be US dollar 2.21 per dollar spent. Administrative claims data suggest that members respond to health plan mailings with an increase in influenza vaccination rates. Health plans can cost-effectively impact medical service utilization and vaccination rates by mailing information to their members.

  14. Performance assessment. Family physicians in Montreal meet the mark!

    PubMed Central

    Goulet, François; Jacques, André; Gagnon, Robert; Bourbeau, Denis; Laberge, Denis; Melanson, Jacques; Ménard, Claude; Racette, Pierre; Rivest, Raymond

    2002-01-01

    OBJECTIVE: To assess the clinical performance of a representative non-volunteer sample of family physicians in metropolitan Montreal, Que. DESIGN: Assessment of clinical performance was based on inspection visits to offices, peer review of medical records, and chart-stimulated recall interviews. The procedure was the one usually followed by the Professional Inspection Committee of the Collège des médecins du Québec. SETTING: Family physicians' practices in metropolitan Montreal. PARTICIPANTS: One hundred randomly selected family physicians. INTERVENTIONS: For each physician, 30 randomly chosen patient charts with data on three to five previous visits were reviewed using explicit criteria and a standard scale using global scores from 1 to 5 (unacceptable to excellent). MAIN OUTCOME MEASURES: Scores were assigned for office practices; record keeping; number of continuing medical education (CME) activities; and quality of clinical performance assessed in terms of investigation plan, diagnostic accuracy, treatment plan, and relevance of care. RESULTS: Overall performance was judged to be good to excellent for 98% of physicians in their private practices; for 90% of physicians concerning CME activities; for 94% of physicians concerning their clinical performance in terms of quality of care; and for 75% of physicians as to record keeping. There was a link between record keeping and quality of care as well as between the number of CME activities and quality of care. CONCLUSION: The overall clinical performance of family physicians in the greater Montreal region is excellent. PMID:12228963

  15. [Relationship between cyberbullying and the suicide related psychological behavior among middle and high school students in Anhui Province].

    PubMed

    Wang, Gengfu; Fang, Yu; Jiang, Liu; Zhou, Guiyang; Yuan, Shanshan; Wang, Xiuxiu; Su, Puyu

    2015-11-01

    To examine the prevalence rate of cyberbullying in middle and high school students in Anhui Province and explore the relationship between cyberbullying and suicide related psychological behavior. A total of 5726 middle and high school students from the 7th to the 12th grades in three regular middle schools and three regular high schools recruited from three cities in the Anhui Province (Tongling, Chuzhou, and Fuyang). Tongling, Chuzhou, and Fuyang are in the south, middle and north of Anhui, respectively. Each city was selected one regular middle school and one regular high school, and 8 classes were selected form each grade from each school. A stratified cluster random sampling method was used to randomly select 5726 participants among the six schools. Self-reports on cyberbullying and suicide related psychological behavior were collected. Among these 5726 adolescents, 46.8% of them involved in cyberbullying. Among them, 3.2% were bullies, 23.8% were victims, and 19.8% were both. Prevalence rates of suicide idea, suicide plan, suicide preparation, suicide implementation were 19.3%, 6.9%, 4.7% and 1.8%, respectively. Cyberbullying involvement, as victims, bullies or bully-victims, increased the risk of four kinds of suicide related psychological behavior (suicide idea, suicide plan, suicide preparation, suicide implementation) (P < 0.05). Cyberbullying has become a common occurrence in middle and high school students. Additionally, cyberbullying is closely related to suicide related psychological behavior among middle and high school students.

  16. Fixed precision sampling plans for white apple leafhopper (Homoptera: Cicadellidae) on apple.

    PubMed

    Beers, Elizabeth H; Jones, Vincent P

    2004-10-01

    Constant precision sampling plans for the white apple leafhopper, Typhlocyba pomaria McAtee, were developed so that it could be used as an indicator species for system stability as new integrated pest management programs without broad-spectrum pesticides are developed. Taylor's power law was used to model the relationship between the mean and the variance, and Green's constant precision sequential sample equation was used to develop sampling plans. Bootstrap simulations of the sampling plans showed greater precision (D = 0.25) than the desired precision (Do = 0.3), particularly at low mean population densities. We found that by adjusting the Do value in Green's equation to 0.4, we were able to reduce the average sample number by 25% and provided an average D = 0.31. The sampling plan described allows T. pomaria to be used as reasonable indicator species of agroecosystem stability in Washington apple orchards.

  17. Addendum to Sampling and Analysis Plan (SAP) for Assessment of LANL-Derived Residual Radionuclides in Soils within Tract A-16-d for Land Conveyance and Transfer for Sewage Treatment Facility Area

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

    Whicker, Jeffrey Jay; Gillis, Jessica Mcdonnel; Ruedig, Elizabeth

    This report summarizes the sampling design used, associated statistical assumptions, as well as general guidelines for conducting post-sampling data analysis. Sampling plan components presented here include how many sampling locations to choose and where within the sampling area to collect those samples. The type of medium to sample (i.e., soil, groundwater, etc.) and how to analyze the samples (in-situ, fixed laboratory, etc.) are addressed in other sections of the sampling plan.

  18. Optimal spatial sampling techniques for ground truth data in microwave remote sensing of soil moisture

    NASA Technical Reports Server (NTRS)

    Rao, R. G. S.; Ulaby, F. T.

    1977-01-01

    The paper examines optimal sampling techniques for obtaining accurate spatial averages of soil moisture, at various depths and for cell sizes in the range 2.5-40 acres, with a minimum number of samples. Both simple random sampling and stratified sampling procedures are used to reach a set of recommended sample sizes for each depth and for each cell size. Major conclusions from statistical sampling test results are that (1) the number of samples required decreases with increasing depth; (2) when the total number of samples cannot be prespecified or the moisture in only one single layer is of interest, then a simple random sample procedure should be used which is based on the observed mean and SD for data from a single field; (3) when the total number of samples can be prespecified and the objective is to measure the soil moisture profile with depth, then stratified random sampling based on optimal allocation should be used; and (4) decreasing the sensor resolution cell size leads to fairly large decreases in samples sizes with stratified sampling procedures, whereas only a moderate decrease is obtained in simple random sampling procedures.

  19. Chi-Squared Test of Fit and Sample Size-A Comparison between a Random Sample Approach and a Chi-Square Value Adjustment Method.

    PubMed

    Bergh, Daniel

    2015-01-01

    Chi-square statistics are commonly used for tests of fit of measurement models. Chi-square is also sensitive to sample size, which is why several approaches to handle large samples in test of fit analysis have been developed. One strategy to handle the sample size problem may be to adjust the sample size in the analysis of fit. An alternative is to adopt a random sample approach. The purpose of this study was to analyze and to compare these two strategies using simulated data. Given an original sample size of 21,000, for reductions of sample sizes down to the order of 5,000 the adjusted sample size function works as good as the random sample approach. In contrast, when applying adjustments to sample sizes of lower order the adjustment function is less effective at approximating the chi-square value for an actual random sample of the relevant size. Hence, the fit is exaggerated and misfit under-estimated using the adjusted sample size function. Although there are big differences in chi-square values between the two approaches at lower sample sizes, the inferences based on the p-values may be the same.

  20. Longitudinal study of health, disease and access to care in rural Victoria: the Crossroads-II study: methods.

    PubMed

    Glenister, Kristen M; Bourke, Lisa; Bolitho, Leslie; Wright, Sian; Roberts, Stuart; Kemp, William; Rhode, Leigh; Bhat, Ravi; Tremper, Sönke; Magliano, Dianna J; Morgan, Mike; Mariño, Rodrigo; Adam, William; Simmons, David

    2018-05-30

    High quality, contemporary data regarding patterns of chronic disease is essential for planning by health services, policy makers and local governments, but surprisingly scarce, including in rural Australia. This dearth of data occurs despite the recognition that rural Australians live with high rates of ill health, poor health behaviours and restricted access to health services. Crossroads-II is set in the Goulburn Valley, a rural region of Victoria, Australia 100-300 km north of metropolitan Melbourne. It is primarily an irrigated agricultural area. The aim of the study is to identify changes in the prevalence of key chronic health conditions including the extent of undiagnosed and undermanaged disease, and association with access to care, over a 15 year period. This study is a 15 year follow up from the 2000-2003 Crossroads-I study (2376 households participated). Crossroads-II includes a similar face to face household survey of 3600 randomly selected households across four towns of sizes 6300 to 49,800 (50% sampled in the larger town with the remainder sampled equally from the three smaller towns). Self-reported health, health behaviour and health service usage information is verified and supplemented in a nested sub-study of 900 randomly selected adult participants in 'clinics' involving a range of additional questionnaires and biophysical measurements. The study is expected to run from October 2016 to December 2018. Besides providing epidemiological and health service utilisation information relating to different diseases and their risk factors in towns of different sizes, the results will be used to develop a composite measure of health service access. The importance of access to health services will be investigated by assessing the correlation of this measure with rates of undiagnosed and undermanaged disease at the mesh block level. Results will be shared with partner organisations to inform service planning and interventions to improve health outcomes for local people.

  1. Planning Future Clinical Trials for Machado-Joseph Disease.

    PubMed

    Saute, Jonas Alex Morales; Jardim, Laura Bannach

    2018-01-01

    Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is an autosomal dominant multiple neurological systems degenerative disorder caused by a CAG repeat expansion at ATXN3 gene. Only a few treatments were evaluated in randomized clinical trials (RCT) in SCA3/MJD patients, with a lack of evidence for both disease-modifying and symptomatic therapies. The present chapter discuss in detail major methodological issues for planning future RCT for SCA3/MJD. There are several potential therapies for SCA3/MJD with encouraging preclinical results. Route of treatment, dosage titration and potential therapy biomarkers might differ among candidate drugs; however, the core study design and protocol will be mostly the same. RCT against placebo group is the best study design to test a disease-modifying therapy; the same cannot be stated for some symptomatic treatments. Main outcomes for future RCT are clinical scales: the Scale for the Assessment and Rating of ataxia (SARA) is currently the instrument of choice to prove efficacy of disease-modifying or symptomatic treatments against ataxia, the most important disease feature. Ataxia quantitative scales or its composite scores can be used as primary outcomes to provide preliminary evidence of efficacy in phase 2 RCT, due to a greater sensitivity to change. Details regarding eligibility criteria, randomization, sample size estimation, duration and type of analysis for both disease modifying and symptomatic treatment trials, were also discussed. Finally, a section anticipates the methodological issues for testing novel drugs when an effective treatment is already available. We conclude emphasizing four points, the first being the need of RCT for a number of different aims in the care of SCA3/MJD. Due to large sample sizes needed to warrant power, RCT for disease-modifying therapies should be multicenter enterprises. There is an urge need for surrogate markers validated for several drug classes. Finally, engagement of at risk or presymptomatic individuals in future trials will enable major advances on treatment research for SCA3/MJD.

  2. Mapping the receptivity of malaria risk to plan the future of control in Somalia

    PubMed Central

    Alegana, Victor Adagi; Patil, Anand Prabhakar; Moloney, Grainne; Borle, Mohammed; Yusuf, Fahmi; Amran, Jamal; Snow, Robert William

    2012-01-01

    Objectives To measure the receptive risks of malaria in Somalia and compare decisions on intervention scale-up based on this map and the more widely used contemporary risk maps. Design Cross-sectional community Plasmodium falciparum parasite rate (PfPR) data for the period 2007–2010 corrected to a standard age range of 2 to <10 years (PfPR2–10) and used within a Bayesian space–time geostatistical framework to predict the contemporary (2010) mean PfPR2–10 and the maximum annual mean PfPR2–10 (receptive) from the highest predicted PfPR2–10 value over the study period as an estimate of receptivity. Setting Randomly sampled communities in Somalia. Participants Randomly sampled individuals of all ages. Main outcome measure Cartographic descriptions of malaria receptivity and contemporary risks in Somalia at the district level. Results The contemporary annual PfPR2–10 map estimated that all districts (n=74) and population (n=8.4 million) in Somalia were under hypoendemic transmission (≤10% PfPR2–10). Of these, 23% of the districts, home to 13% of the population, were under transmission of <1% PfPR2–10. About 58% of the districts and 55% of the population were in the risk class of 1% to <5% PfPR2–10. In contrast, the receptivity map estimated 65% of the districts and 69% of the population were under mesoendemic transmission (>10%–50% PfPR2–10) and the rest as hypoendemic. Conclusion Compared with maps of receptive risks, contemporary maps of transmission mask disparities of malaria risk necessary to prioritise and sustain future control. As malaria risk declines across Africa, efforts must be invested in measuring receptivity for efficient control planning. PMID:22855625

  3. An Evaluation of the Effectiveness of Recruitment Methods: The Staying Well after Depression Randomized Controlled Trial

    PubMed Central

    Krusche, Adele; Rudolf von Rohr, Isabelle; Muse, Kate; Duggan, Danielle; Crane, Catherine; Williams, J. Mark G.

    2014-01-01

    Background Randomized controlled trials (RCTs) are widely accepted as being the most efficient way of investigating the efficacy of psychological therapies. However, researchers conducting RCTs commonly report difficulties recruiting an adequate sample within planned timescales. In an effort to overcome recruitment difficulties, researchers often are forced to expand their recruitment criteria or extend the recruitment phase, thus increasing costs and delaying publication of results. Research investigating the effectiveness of recruitment strategies is limited and trials often fail to report sufficient details about the recruitment sources and resources utilised. Purpose We examined the efficacy of strategies implemented during the Staying Well after Depression RCT in Oxford to recruit participants with a history of recurrent depression. Methods We describe eight recruitment methods utilised and two further sources not initiated by the research team and examine their efficacy in terms of (i) the return, including the number of potential participants who contacted the trial and the number who were randomized into the trial, (ii) cost-effectiveness, comprising direct financial cost and manpower for initial contacts and randomized participants, and (iii) comparison of sociodemographic characteristics of individuals recruited from different sources. Results Poster advertising, web-based advertising and mental health worker referrals were the cheapest methods per randomized participant; however, the ratio of randomized participants to initial contacts differed markedly per source. Advertising online, via posters and on a local radio station were the most cost-effective recruitment methods for soliciting participants who subsequently were randomized into the trial. Advertising across many sources (saturation) was found to be important. Limitations It may not be feasible to employ all the recruitment methods used in this trial to obtain participation from other populations, such as those currently unwell, or in other geographical locations. Recruitment source was unavailable for participants who could not be reached after the initial contact. Thus, it is possible that the efficiency of certain methods of recruitment was poorer than estimated. Efficacy and costs of other recruitment initiatives, such as providing travel expenses to the in-person eligibility assessment and making follow-up telephone calls to candidates who contacted the recruitment team but could not be screened promptly, were not analysed. Conclusions Website advertising resulted in the highest number of randomized participants and was the second cheapest method of recruiting. Future research should evaluate the effectiveness of recruitment strategies for other samples to contribute to a comprehensive base of knowledge for future RCTs. PMID:24686105

  4. An evaluation of the effectiveness of recruitment methods: the staying well after depression randomized controlled trial.

    PubMed

    Krusche, Adele; Rudolf von Rohr, Isabelle; Muse, Kate; Duggan, Danielle; Crane, Catherine; Williams, J Mark G

    2014-04-01

    Randomized controlled trials (RCTs) are widely accepted as being the most efficient way of investigating the efficacy of psychological therapies. However, researchers conducting RCTs commonly report difficulties in recruiting an adequate sample within planned timescales. In an effort to overcome recruitment difficulties, researchers often are forced to expand their recruitment criteria or extend the recruitment phase, thus increasing costs and delaying publication of results. Research investigating the effectiveness of recruitment strategies is limited, and trials often fail to report sufficient details about the recruitment sources and resources utilized. We examined the efficacy of strategies implemented during the Staying Well after Depression RCT in Oxford to recruit participants with a history of recurrent depression. We describe eight recruitment methods utilized and two further sources not initiated by the research team and examine their efficacy in terms of (1) the return, including the number of potential participants who contacted the trial and the number who were randomized into the trial; (2) cost-effectiveness, comprising direct financial cost and manpower for initial contacts and randomized participants; and (3) comparison of sociodemographic characteristics of individuals recruited from different sources. Poster advertising, web-based advertising, and mental health worker referrals were the cheapest methods per randomized participant; however, the ratio of randomized participants to initial contacts differed markedly per source. Advertising online, via posters, and on a local radio station were the most cost-effective recruitment methods for soliciting participants who subsequently were randomized into the trial. Advertising across many sources (saturation) was found to be important. It may not be feasible to employ all the recruitment methods used in this trial to obtain participation from other populations, such as those currently unwell, or in other geographical locations. Recruitment source was unavailable for participants who could not be reached after the initial contact. Thus, it is possible that the efficiency of certain methods of recruitment was poorer than estimated. Efficacy and costs of other recruitment initiatives, such as providing travel expenses to the in-person eligibility assessment and making follow-up telephone calls to candidates who contacted the recruitment team but could not be screened promptly, were not analysed. Website advertising resulted in the highest number of randomized participants and was the second cheapest method of recruiting. Future research should evaluate the effectiveness of recruitment strategies for other samples to contribute to a comprehensive base of knowledge for future RCTs.

  5. Cluster randomized trials utilizing primary care electronic health records: methodological issues in design, conduct, and analysis (eCRT Study).

    PubMed

    Gulliford, Martin C; van Staa, Tjeerd P; McDermott, Lisa; McCann, Gerard; Charlton, Judith; Dregan, Alex

    2014-06-11

    There is growing interest in conducting clinical and cluster randomized trials through electronic health records. This paper reports on the methodological issues identified during the implementation of two cluster randomized trials using the electronic health records of the Clinical Practice Research Datalink (CPRD). Two trials were completed in primary care: one aimed to reduce inappropriate antibiotic prescribing for acute respiratory infection; the other aimed to increase physician adherence with secondary prevention interventions after first stroke. The paper draws on documentary records and trial datasets to report on the methodological experience with respect to research ethics and research governance approval, general practice recruitment and allocation, sample size calculation and power, intervention implementation, and trial analysis. We obtained research governance approvals from more than 150 primary care organizations in England, Wales, and Scotland. There were 104 CPRD general practices recruited to the antibiotic trial and 106 to the stroke trial, with the target number of practices being recruited within six months. Interventions were installed into practice information systems remotely over the internet. The mean number of participants per practice was 5,588 in the antibiotic trial and 110 in the stroke trial, with the coefficient of variation of practice sizes being 0.53 and 0.56 respectively. Outcome measures showed substantial correlations between the 12 months before, and after intervention, with coefficients ranging from 0.42 for diastolic blood pressure to 0.91 for proportion of consultations with antibiotics prescribed, defining practice and participant eligibility for analysis requires careful consideration. Cluster randomized trials may be performed efficiently in large samples from UK general practices using the electronic health records of a primary care database. The geographical dispersal of trial sites presents a difficulty for research governance approval and intervention implementation. Pretrial data analyses should inform trial design and analysis plans. Current Controlled Trials ISRCTN 47558792 and ISRCTN 35701810 (both registered on 17 March 2010).

  6. Cluster randomized trials utilizing primary care electronic health records: methodological issues in design, conduct, and analysis (eCRT Study)

    PubMed Central

    2014-01-01

    Background There is growing interest in conducting clinical and cluster randomized trials through electronic health records. This paper reports on the methodological issues identified during the implementation of two cluster randomized trials using the electronic health records of the Clinical Practice Research Datalink (CPRD). Methods Two trials were completed in primary care: one aimed to reduce inappropriate antibiotic prescribing for acute respiratory infection; the other aimed to increase physician adherence with secondary prevention interventions after first stroke. The paper draws on documentary records and trial datasets to report on the methodological experience with respect to research ethics and research governance approval, general practice recruitment and allocation, sample size calculation and power, intervention implementation, and trial analysis. Results We obtained research governance approvals from more than 150 primary care organizations in England, Wales, and Scotland. There were 104 CPRD general practices recruited to the antibiotic trial and 106 to the stroke trial, with the target number of practices being recruited within six months. Interventions were installed into practice information systems remotely over the internet. The mean number of participants per practice was 5,588 in the antibiotic trial and 110 in the stroke trial, with the coefficient of variation of practice sizes being 0.53 and 0.56 respectively. Outcome measures showed substantial correlations between the 12 months before, and after intervention, with coefficients ranging from 0.42 for diastolic blood pressure to 0.91 for proportion of consultations with antibiotics prescribed, defining practice and participant eligibility for analysis requires careful consideration. Conclusions Cluster randomized trials may be performed efficiently in large samples from UK general practices using the electronic health records of a primary care database. The geographical dispersal of trial sites presents a difficulty for research governance approval and intervention implementation. Pretrial data analyses should inform trial design and analysis plans. Trial registration Current Controlled Trials ISRCTN 47558792 and ISRCTN 35701810 (both registered on 17 March 2010). PMID:24919485

  7. Adolescent Substance Use in the Multimodal Treatment Study of Attention-Deficit/Hyperactivity Disorder (ADHD) (MTA) as a Function of Childhood ADHD, Random Assignment to Childhood Treatments, and Subsequent Medication

    PubMed Central

    Molina, Brooke S.G.; Hinshaw, Stephen P.; Arnold, L. Eugene; Swanson, James M.; Pelham, William E.; Hechtman, Lily; Hoza, Betsy; Epstein, Jeffery N.; Wigal, Timothy; Abikoff, Howard B.; Greenhill, Laurence L.; Jensen, Peter S.; Wells, Karen C.; Vitiello, Benedetto; Gibbons, Robert D.; Howard, Andrea; Houck, Patricia R.; Hur, Kwan; Lu, Bo; Marcus, Sue

    2013-01-01

    Objectives To determine long-term effects on substance use and substance use disorder (SUD), up to 8 years after childhood enrollment, of the randomly assigned 14-month treatments in the multisite Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (MTA; n=436); to test whether (a) medication at follow-up, (b) cumulative psychostimulant treatment over time, or (c) both relate to substance use/SUD; to compare substance use/SUD in the ADHD sample to the non-ADHD childhood classmate comparison group (n=261). Method Mixed-effects regression models with planned contrasts were used for all tests except the important cumulative stimulant treatment question, for which propensity score matching analysis was used. Results The originally randomized treatment groups did not differ significantly on substance use/SUD by the 8 year follow-up or earlier (M age = 17 years). Neither medication at follow-up (mostly stimulants) nor cumulative stimulant treatment was associated with adolescent substance use/SUD. Substance use at all time points, including use of two or more substances and SUD, were each greater in the ADHD than non-ADHD samples, regardless of sex. Conclusions Medication for ADHD did not protect from, nor contribute to, visible risk of substance use or SUD by adolescence, whether analyzed as randomized treatment assignment in childhood, as medication at follow-up, or as cumulative stimulant treatment over an 8 year follow-up from childhood. These results suggest the need to identify alternative or adjunctive adolescent-focused approaches to substance abuse prevention and treatment for boys and girls with ADHD, especially given their increased risk for use and abuse of multiple substances that is not improved with stimulant medication. Clinical trial registration information—Multimodal Treatment Study of Children with Attention Deficit and Hyperactivity Disorder (MTA); http://clinical trials.gov/; NCT00000388. PMID:23452682

  8. Implementation of a 4-y, high-fiber, high-fruit-and-vegetable, low-fat dietary intervention: results of dietary changes in the Polyp Prevention Trial.

    PubMed

    Lanza, E; Schatzkin, A; Daston, C; Corle, D; Freedman, L; Ballard-Barbash, R; Caan, B; Lance, P; Marshall, J; Iber, F; Shike, M; Weissfeld, J; Slattery, M; Paskett, E; Mateski, D; Albert, P

    2001-09-01

    The Polyp Prevention Trial (PPT) was a multicenter randomized clinical trial designed to determine the effects of a high-fiber (4.30 g/MJ), high-fruit-and-vegetable (0.84 servings/MJ), low-fat (20% of energy from fat) diet on the recurrence of adenomatous polyps in the large bowel. Our goal was to determine whether the PPT intervention plan could effect change in 3 dietary goals and to examine the intervention's effect on the intake of other food groups and nutrients. Participants with large-bowel adenomatous polyps diagnosed in the past 6 mo were randomly assigned to either the intervention (n = 1037) or the control (n = 1042) group and remained in the trial for 4 y. Three dietary assessment instruments were used to measure dietary change: food-frequency questionnaires (in 100% of the sample), 4-d food records (in a 20% random cohort), and 24-h dietary recalls (in a 10% random sample). Intervention participants made and sustained significant changes in all PPT goals as measured by the dietary assessment instruments; the control participants' intakes remained essentially the same throughout the trial. The absolute differences between the intervention and control groups over the 4-y period were 9.7% of energy from fat (95% CI: 9.0%, 10.3%), 1.65 g dietary fiber/MJ (95% CI: 1.53, 1.74), and 0.27 servings of fruit and vegetables/MJ (95% CI: 0.25, 0.29). Intervention participants also reported significant changes in the intake of other nutrients and food groups. The intervention group also had significantly higher serum carotenoid concentrations and lower body weights than did the control group. Motivated, free-living individuals, given appropriate support, can make and sustain major dietary changes over a 4-y period.

  9. Adolescent substance use in the multimodal treatment study of attention-deficit/hyperactivity disorder (ADHD) (MTA) as a function of childhood ADHD, random assignment to childhood treatments, and subsequent medication.

    PubMed

    Molina, Brooke S G; Hinshaw, Stephen P; Eugene Arnold, L; Swanson, James M; Pelham, William E; Hechtman, Lily; Hoza, Betsy; Epstein, Jeffery N; Wigal, Timothy; Abikoff, Howard B; Greenhill, Laurence L; Jensen, Peter S; Wells, Karen C; Vitiello, Benedetto; Gibbons, Robert D; Howard, Andrea; Houck, Patricia R; Hur, Kwan; Lu, Bo; Marcus, Sue

    2013-03-01

    To determine long-term effects on substance use and substance use disorder (SUD), up to 8 years after childhood enrollment, of the randomly assigned 14-month treatments in the multisite Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (MTA; n = 436); to test whether medication at follow-up, cumulative psychostimulant treatment over time, or both relate to substance use/SUD; and to compare substance use/SUD in the ADHD sample to the non-ADHD childhood classmate comparison group (n = 261). Mixed-effects regression models with planned contrasts were used for all tests except the important cumulative stimulant treatment question, for which propensity score matching analysis was used. The originally randomized treatment groups did not differ significantly on substance use/SUD by the 8-year follow-up or earlier (mean age = 17 years). Neither medication at follow-up (mostly stimulants) nor cumulative stimulant treatment was associated with adolescent substance use/SUD. Substance use at all time points, including use of two or more substances and SUD, were each greater in the ADHD than in the non-ADHD samples, regardless of sex. Medication for ADHD did not protect from, or contribute to, visible risk of substance use or SUD by adolescence, whether analyzed as randomized treatment assignment in childhood, as medication at follow-up, or as cumulative stimulant treatment over an 8-year follow-up from childhood. These results suggest the need to identify alternative or adjunctive adolescent-focused approaches to substance abuse prevention and treatment for boys and girls with ADHD, especially given their increased risk for use and abuse of multiple substances that is not improved with stimulant medication. Clinical trial registration information-Multimodal Treatment Study of Children With Attention Deficit and Hyperactivity Disorder (MTA); http://clinical trials.gov/; NCT00000388. Copyright © 2013 American Academy of Child and Adolescent Psychiatry. All rights reserved.

  10. Theory-Based Interventions Combining Mental Simulation and Planning Techniques to Improve Physical Activity: Null Results from Two Randomized Controlled Trials.

    PubMed

    Meslot, Carine; Gauchet, Aurélie; Allenet, Benoît; François, Olivier; Hagger, Martin S

    2016-01-01

    Interventions to assist individuals in initiating and maintaining regular participation in physical activity are not always effective. Psychological and behavioral theories advocate the importance of both motivation and volition in interventions to change health behavior. Interventions adopting self-regulation strategies that foster motivational and volitional components may, therefore, have utility in promoting regular physical activity participation. We tested the efficacy of an intervention adopting motivational (mental simulation) and volitional (implementation intentions) components to promote a regular physical activity in two studies. Study 1 adopted a cluster randomized design in which participants ( n = 92) were allocated to one of three conditions: mental simulation plus implementation intention, implementation intention only, or control. Study 2 adopted a 2 (mental simulation vs. no mental simulation) × 2 (implementation intention vs. no implementation intention) randomized controlled design in which fitness center attendees ( n = 184) were randomly allocated one of four conditions: mental simulation only, implementation intention only, combined, or control. Physical activity behavior was measured by self-report (Study 1) or fitness center attendance (Study 2) at 4- (Studies 1 and 2) and 19- (Study 2 only) week follow-up periods. Findings revealed no statistically significant main or interactive effects of the mental simulation and implementation intention conditions on physical activity outcomes in either study. Findings are in contrast to previous research which has found pervasive effects for both intervention strategies. Findings are discussed in light of study limitations including the relatively small sample sizes, particularly for Study 1, deviations in the operationalization of the intervention components from previous research and the lack of a prompt for a goal intention. Future research should focus on ensuring uniformity in the format of the intervention components, test the effects of each component alone and in combination using standardized measures across multiple samples, and systematically explore effects of candidate moderators.

  11. Theory-Based Interventions Combining Mental Simulation and Planning Techniques to Improve Physical Activity: Null Results from Two Randomized Controlled Trials

    PubMed Central

    Meslot, Carine; Gauchet, Aurélie; Allenet, Benoît; François, Olivier; Hagger, Martin S.

    2016-01-01

    Interventions to assist individuals in initiating and maintaining regular participation in physical activity are not always effective. Psychological and behavioral theories advocate the importance of both motivation and volition in interventions to change health behavior. Interventions adopting self-regulation strategies that foster motivational and volitional components may, therefore, have utility in promoting regular physical activity participation. We tested the efficacy of an intervention adopting motivational (mental simulation) and volitional (implementation intentions) components to promote a regular physical activity in two studies. Study 1 adopted a cluster randomized design in which participants (n = 92) were allocated to one of three conditions: mental simulation plus implementation intention, implementation intention only, or control. Study 2 adopted a 2 (mental simulation vs. no mental simulation) × 2 (implementation intention vs. no implementation intention) randomized controlled design in which fitness center attendees (n = 184) were randomly allocated one of four conditions: mental simulation only, implementation intention only, combined, or control. Physical activity behavior was measured by self-report (Study 1) or fitness center attendance (Study 2) at 4- (Studies 1 and 2) and 19- (Study 2 only) week follow-up periods. Findings revealed no statistically significant main or interactive effects of the mental simulation and implementation intention conditions on physical activity outcomes in either study. Findings are in contrast to previous research which has found pervasive effects for both intervention strategies. Findings are discussed in light of study limitations including the relatively small sample sizes, particularly for Study 1, deviations in the operationalization of the intervention components from previous research and the lack of a prompt for a goal intention. Future research should focus on ensuring uniformity in the format of the intervention components, test the effects of each component alone and in combination using standardized measures across multiple samples, and systematically explore effects of candidate moderators. PMID:27899904

  12. [Tobacco quality analysis of producing areas of Yunnan tobacco using near-infrared (NIR) spectrum].

    PubMed

    Wang, Yi; Ma, Xiang; Wen, Ya-Dong; Yu, Chun-Xia; Wang, Luo-Ping; Zhao, Long-Lian; Li, Jun-Hui

    2013-01-01

    In the present study, tobacco quality analysis of different producing areas was carried out applying spectrum projection and correlation methods. The group of industrial classification data was near-infrared (NIR) spectrum in 2010 year of middle parts of tobacco plant from Hongta Tobacco (Group) Co., Ltd. Twelve hundred seventy six superior tobacco leaf samples were collected from four producing areas, in which three areas from Yuxi, Chuxiong and Zhaotong, in Yunnan province all belong to tobacco varieties of K326 and one area from Dali belongs to tobacco varieties of Hongda. The conclusion showed that when the samples were divided into two parts by the ratio of 2 : 1 randomly as analysis and verification sets, the verification set corresponded with the analysis set applying spectrum projection because their correlation coefficients by the first and second dimensional projection were all above 0.99. At the same time, The study discussed a method to get the quantitative similarity values of different producing areas samples. The similarity values were instructive in tobacco plant planning, quality management, acquisition of raw materials of tobacco and tobacco leaf blending.

  13. Designing a two-rank acceptance sampling plan for quality inspection of geospatial data products

    NASA Astrophysics Data System (ADS)

    Tong, Xiaohua; Wang, Zhenhua; Xie, Huan; Liang, Dan; Jiang, Zuoqin; Li, Jinchao; Li, Jun

    2011-10-01

    To address the disadvantages of classical sampling plans designed for traditional industrial products, we originally propose a two-rank acceptance sampling plan (TRASP) for the inspection of geospatial data outputs based on the acceptance quality level (AQL). The first rank sampling plan is to inspect the lot consisting of map sheets, and the second is to inspect the lot consisting of features in an individual map sheet. The TRASP design is formulated as an optimization problem with respect to sample size and acceptance number, which covers two lot size cases. The first case is for a small lot size with nonconformities being modeled by a hypergeometric distribution function, and the second is for a larger lot size with nonconformities being modeled by a Poisson distribution function. The proposed TRASP is illustrated through two empirical case studies. Our analysis demonstrates that: (1) the proposed TRASP provides a general approach for quality inspection of geospatial data outputs consisting of non-uniform items and (2) the proposed acceptance sampling plan based on TRASP performs better than other classical sampling plans. It overcomes the drawbacks of percent sampling, i.e., "strictness for large lot size, toleration for small lot size," and those of a national standard used specifically for industrial outputs, i.e., "lots with different sizes corresponding to the same sampling plan."

  14. The study of combining Latin Hypercube Sampling method and LU decomposition method (LULHS method) for constructing spatial random field

    NASA Astrophysics Data System (ADS)

    WANG, P. T.

    2015-12-01

    Groundwater modeling requires to assign hydrogeological properties to every numerical grid. Due to the lack of detailed information and the inherent spatial heterogeneity, geological properties can be treated as random variables. Hydrogeological property is assumed to be a multivariate distribution with spatial correlations. By sampling random numbers from a given statistical distribution and assigning a value to each grid, a random field for modeling can be completed. Therefore, statistics sampling plays an important role in the efficiency of modeling procedure. Latin Hypercube Sampling (LHS) is a stratified random sampling procedure that provides an efficient way to sample variables from their multivariate distributions. This study combines the the stratified random procedure from LHS and the simulation by using LU decomposition to form LULHS. Both conditional and unconditional simulations of LULHS were develpoed. The simulation efficiency and spatial correlation of LULHS are compared to the other three different simulation methods. The results show that for the conditional simulation and unconditional simulation, LULHS method is more efficient in terms of computational effort. Less realizations are required to achieve the required statistical accuracy and spatial correlation.

  15. Efficacy of Standardized Extract of Bacopa monnieri (Bacognize®) on Cognitive Functions of Medical Students: A Six-Week, Randomized Placebo-Controlled Trial

    PubMed Central

    Abichandani, L. G.; Thawani, Vijay; Gharpure, K. J.; Naidu, M. U. R.; Venkat Ramana, G.

    2016-01-01

    Rationale. Bacopa monnieri, popularly known as Brahmi, has been traditionally used in Ayurveda since ages for its memory enhancing properties. However, data on placebo-controlled trial of Bacopa monnieri on intellectual sample is scarce. Hence this study was planned to evaluate the effect of Bacopa monnieri on memory of medical students for six weeks. Objective. To evaluate the efficacy of Bacopa monnieri on memory of medical students with six weeks' administration. Method and Material. This was a randomized double blind placebo-controlled noncrossover, parallel trial. Sixty medical students of either gender from second year of medical school, third term, regular batch, were enrolled from Government Medical College, Nagpur, India. Baseline biochemical and memory tests were done. The participants were randomly divided in two groups to receive either 150 mg of standardized extract of Bacopa monnieri (Bacognize) or matching placebo twice daily for six weeks. All baseline investigations were repeated at the end of the trial. Students were followed up for 15 days after the intervention. Results. Statistically significant improvement was seen in the tests relating to the cognitive functions with use of Bacopa monnieri. Blood biochemistry also showed a significant increase in serum calcium levels (still within normal range). PMID:27803728

  16. Show Me My Health Plans: a study protocol of a randomized trial testing a decision support tool for the federal health insurance marketplace in Missouri.

    PubMed

    Politi, Mary C; Barker, Abigail R; Kaphingst, Kimberly A; McBride, Timothy; Shacham, Enbal; Kebodeaux, Carey S

    2016-02-16

    The implementation of the ACA has improved access to quality health insurance, a necessary first step to improving health outcomes. However, access must be supplemented by education to help individuals make informed choices for plans that meet their individual financial and health needs. Drawing on a model of information processing and on prior research, we developed a health insurance decision support tool called Show Me My Health Plans. Developed with extensive stakeholder input, the current tool (1) simplifies information through plain language and graphics in an educational component; (2) assesses and reviews knowledge interactively to ensure comprehension of key material; (3) incorporates individual and/or family health status to personalize out-of-pocket cost estimates; (4) assesses preferences for plan features; and (5) helps individuals weigh information appropriate to their interests and needs through a summary page with "good fit" plans generated from a tailored algorithm. The current study will evaluate whether the online decision support tool improves health insurance decisions compared to a usual care condition (the healthcare.gov marketplace website). The trial will include 362 individuals (181 in each group) from rural, suburban, and urban settings within a 90 mile radius around St. Louis. Eligibility criteria includes English-speaking individuals 18-64 years old who are eligible for the ACA marketplace plans. They will be computer randomized to view the intervention or usual care condition. Presenting individuals with options that they can understand tailored to their needs and preferences could help improve decision quality. By helping individuals narrow down the complexity of health insurance plan options, decision support tools such as this one could prepare individuals to better navigate enrollment in a plan that meets their individual needs. The randomized trial was registered in clinicaltrials.gov (NCT02522624) on August 6, 2015.

  17. Effect of Sampling Plans on the Risk of Escherichia coli O157 Illness.

    PubMed

    Kiermeier, Andreas; Sumner, John; Jenson, Ian

    2015-07-01

    Australia exports about 150,000 to 200,000 tons of manufacturing beef to the United States annually. Each lot is tested for Escherichia coli O157 using the N-60 sampling protocol, where 60 small pieces of surface meat from each lot of production are tested. A risk assessment of E. coli O157 illness from the consumption of hamburgers made from Australian manufacturing meat formed the basis to evaluate the effect of sample size and amount on the number of illnesses predicted. The sampling plans evaluated included no sampling (resulting in an estimated 55.2 illnesses per annum), the current N-60 plan (50.2 illnesses), N-90 (49.6 illnesses), N-120 (48.4 illnesses), and a more stringent N-60 sampling plan taking five 25-g samples from each of 12 cartons (47.4 illnesses per annum). While sampling may detect some highly contaminated lots, it does not guarantee that all such lots are removed from commerce. It is concluded that increasing the sample size or sample amount from the current N-60 plan would have a very small public health effect.

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

    Anheier, Norman C.; Cannon, Bret D.; Martinez, Alonzo

    The International Atomic Energy Agency’s (IAEA’s) long-term research and development plan calls for more cost-effective and efficient safeguard methods to detect and deter misuse of gaseous centrifuge enrichment plants (GCEPs). The IAEA’s current safeguards approaches at GCEPs are based on a combination of routine and random inspections that include environmental sampling and destructive assay (DA) sample collection from UF6 in-process material and selected cylinders. Samples are then shipped offsite for subsequent laboratory analysis. In this paper, a new DA sample collection and onsite analysis approach that could help to meet challenges in transportation and chain of custody for UF6 DAmore » samples is introduced. This approach uses a handheld sampler concept and a Laser Ablation, Laser Absorbance Spectrometry (LAARS) analysis instrument, both currently under development at the Pacific Northwest National Laboratory. A LAARS analysis instrument could be temporarily or permanently deployed in the IAEA control room of the facility, in the IAEA data acquisition cabinet, for example. The handheld PNNL DA sampler design collects and stabilizes a much smaller DA sample mass compared to current sampling methods. The significantly lower uranium mass reduces the sample radioactivity and the stabilization approach diminishes the risk of uranium and hydrogen fluoride release. These attributes enable safe sample handling needed during onsite LAARS assay and may help ease shipping challenges for samples to be processed at the IAEA’s offsite laboratory. The LAARS and DA sampler implementation concepts will be described and preliminary technical viability results presented.« less

  19. PlanYourLifeSpan.org - an intervention to help seniors make choices for their fourth quarter of life: Results from the randomized clinical trial.

    PubMed

    Lindquist, Lee A; Ramirez-Zohfeld, Vanessa; Sunkara, Priya D; Forcucci, Chris; Campbell, Dianne S; Mitzen, Phyllis; Ciolino, Jody D; Gregory, Dyanna; Kricke, Gayle; Cameron, Kenzie A

    2017-11-01

    Few older adults contemplate their home support and health needs that may be required for aging-in-place. We sought to assess the efficacy of PlanYourLifespan.org (PYL), in influencing seniors' planning behaviors, perception of the importance of planning, and confidence accessing services. Randomized controlled trial, of adults, age ≥65 years in urban, suburban, rural areas of Texas, Illinois, Indiana. Among 385 participants, mean age was 71.9 years, 79.5% female. Between baseline and one-month follow-up, average planning behavior score increased 0.22 points in the PYL arm when compared to the attention control (AC) arm. After controlling for baseline, mean one-month planning behavior score was significantly higher in the PYL arm than in the AC arm (1.25 points, CI 0.37-2.12, p=0.005). Secondary analyses via longitudinal linear mixed modelling suggested a study arm-by-time interaction effect for both planning behavior (p=0.047 and perception of importance (p=0.05). Significant baseline covariates included self-efficacy, education, perceived social support, power of attorney, and history of stroke. PlanYourLifespan.org demonstrated efficacy in helping seniors plan for and communicate their health support needs. This free, nationally available tool may help individuals understand, plan, and communicate their options for their future support needs. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. A Cluster Randomized Controlled Trial of the MyFamilyPlan Online Preconception Health Education Tool.

    PubMed

    Batra, Priya; Mangione, Carol M; Cheng, Eric; Steers, W Neil; Nguyen, Tina A; Bell, Douglas; Kuo, Alice A; Gregory, Kimberly D

    2018-05-01

    To evaluate whether exposure to MyFamilyPlan-a web-based preconception health education module-changes the proportion of women discussing reproductive health with providers at well-woman visits. Cluster randomized controlled trial. One hundred thirty participants per arm distributed among 34 clusters (physicians) required to detect a 20% change in the primary outcome. Urban academic medical center (California). Eligible women were 18 to 45 years old, were English speaking, were nonpregnant, were able to access the Internet, and had an upcoming well-woman visit. E-mail and phone recruitment between September 2015 and May 2016; 292 enrollees randomized. Intervention participants completed the MyFamilyPlan module online 7 to 10 days before a scheduled well-woman visit; control participants reviewed standard online preconception health education materials. The primary outcome was self-reported discussion of reproductive health with the physician at the well-woman visit. Self-reported secondary outcomes were folic acid use, contraceptive method initiation/change, and self-efficacy score. Multilevel multivariate logistic regression. After adjusting for covariates and cluster, exposure to MyFamilyPlan was the only variable significantly associated with an increase in the proportion of women discussing reproductive health with providers (odds ratio: 1.97, 95% confidence interval: 1.22-3.19). Prespecified secondary outcomes were unaffected. MyFamilyPlan exposure was associated with a significant increase in the proportion of women who reported discussing reproductive health with providers and may promote preconception health awareness; more work is needed to affect associated behaviors.

  1. Feasibility of a randomized controlled trial to evaluate the impact of decision boxes on shared decision-making processes.

    PubMed

    Giguere, Anik Mc; Labrecque, Michel; Légaré, France; Grad, Roland; Cauchon, Michel; Greenway, Matthew; Haynes, R Brian; Pluye, Pierre; Syed, Iqra; Banerjee, Debi; Carmichael, Pierre-Hugues; Martin, Mélanie

    2015-02-25

    Decision boxes (DBoxes) are two-page evidence summaries to prepare clinicians for shared decision making (SDM). We sought to assess the feasibility of a clustered Randomized Controlled Trial (RCT) to evaluate their impact. A convenience sample of clinicians (nurses, physicians and residents) from six primary healthcare clinics who received eight DBoxes and rated their interest in the topic and satisfaction. After consultations, their patients rated their involvement in decision-making processes (SDM-Q-9 instrument). We measured clinic and clinician recruitment rates, questionnaire completion rates, patient eligibility rates, and estimated the RCT needed sample size. Among the 20 family medicine clinics invited to participate in this study, four agreed to participate, giving an overall recruitment rate of 20%. Of 148 clinicians invited to the study, 93 participated (63%). Clinicians rated an interest in the topics ranging 6.4-8.2 out of 10 (with 10 highest) and a satisfaction with DBoxes of 4 or 5 out of 5 (with 5 highest) for 81% DBoxes. For the future RCT, we estimated that a sample size of 320 patients would allow detecting a 9% mean difference in the SDM-Q-9 ratings between our two arms (0.02 ICC; 0.05 significance level; 80% power). Clinicians' recruitment and questionnaire completion rates support the feasibility of the planned RCT. The level of interest of participants for the DBox topics, and their level of satisfaction with the Dboxes demonstrate the acceptability of the intervention. Processes to recruit clinics and patients should be optimized.

  2. Nevada National Security Site Integrated Groundwater Sampling Plan, Revision 1

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

    Wilborn, Bill R.; Boehlecke, Robert F.

    The purpose is to provide a comprehensive, integrated approach for collecting and analyzing groundwater samples to meet the needs and objectives of the DOE/EM Nevada Program’s UGTA Activity. Implementation of this Plan will provide high-quality data required by the UGTA Activity for ensuring public protection in an efficient and cost-effective manner. The Plan is designed to ensure compliance with the UGTA Quality Assurance Plan (QAP) (NNSA/NFO, 2015); Federal Facility Agreement and Consent Order (FFACO) (1996, as amended); and DOE Order 458.1, Radiation Protection of the Public and the Environment (DOE, 2013). The Plan’s scope comprises sample collection and analysis requirementsmore » relevant to assessing both the extent of groundwater contamination from underground nuclear testing and impact of testing on water quality in downgradient communities. This Plan identifies locations to be sampled by CAU and location type, sampling frequencies, sample collection methodologies, and the constituents to be analyzed. In addition, the Plan defines data collection criteria such as well purging, detection levels, and accuracy requirements/recommendations; identifies reporting and data management requirements; and provides a process to ensure coordination between NNSS groundwater sampling programs for sampling analytes of interest to UGTA. Information used in the Plan development—including the rationale for selection of wells, sampling frequency, and the analytical suite—is discussed under separate cover (N-I, 2014) and is not reproduced herein. This Plan does not address compliance for those wells involved in a permitted activity. Sampling and analysis requirements associated with these wells are described in their respective permits and are discussed in NNSS environmental reports (see Section 5.2). In addition, sampling for UGTA CAUs that are in the Closure Report (CR) stage are not included in this Plan. Sampling requirements for these CAUs are described in the CR. Frenchman Flat is currently the only UGTA CAU in the CR stage. Sampling requirements for this CAU are described in Underground Test Area (UGTA) Closure Report for Corrective Action Unit 98: Frenchman Flat Nevada National Security Site, Nevada (NNSA/NFO, 2016).« less

  3. Implementing trials of complex interventions in community settings: The USC – Rancho Los Amigos Pressure Ulcer Prevention Study (PUPS)

    PubMed Central

    Clark, Florence; Pyatak, Elizabeth A.; Carlson, Mike; Blanche, Erna Imperatore; Vigen, Cheryl; Hay, Joel; Mallinson, Trudy; Blanchard, Jeanine; Unger, Jennifer B.; Garber, Susan L.; Diaz, Jesus; Florindez, Lucia I.; Atkins, Michal; Rubayi, Salah; Azen, Stanley Paul

    2014-01-01

    Background Randomized trials of complex, non-pharmacologic interventions implemented in home and community settings, such as the University of Southern California (USC)–Rancho Los Amigos National Rehabilitation Center (RLANRC) Pressure Ulcer Prevention Study (PUPS), present unique challenges with respect to: (a) participant recruitment and retention, (b) intervention delivery and fidelity, (c) randomization and assessment, and (d) potential inadvertent treatment effects. Purpose We describe the methods employed to address the challenges confronted in implementing PUPS. In this randomized controlled trial, we are assessing the efficacy of a complex, preventive intervention in reducing the incidence of, and costs associated with, the development of medically serious pressure ulcers in people with spinal cord injury. Method Individuals with spinal cord injury recruited from RLANRC were assigned to either a 12-month preventive intervention group or a standard care control group. The primary outcome is the incidence of serious pressure ulcers with secondary endpoints including ulcer-related surgeries, medical treatment costs, and quality of life. These outcomes are assessed at 12 and 24 months after randomization. Additionally, we are studying the mediating mechanisms that account for intervention outcomes. Results PUPS has been successfully implemented, including recruitment of the target sample size of 170 participants, assurance of the integrity of intervention protocol delivery with an average 90% treatment adherence rate, and enactment of the assessment plan. However, implementation has been replete with challenges. To meet recruitment goals, we instituted a five-pronged approach customized for an underserved, ethnically diverse population. In intervention delivery, we increased staff time to overcome economic and cultural barriers to retention and adherence. To ensure treatment fidelity and replicability, we monitored intervention protocol delivery in accord with a rigorous plan. Finally, we have overcome unanticipated assessment and design concerns related to: (a) determining pressure ulcer incidence/severity, (b) randomization imbalance, and (c) inadvertent potential control group contamination. Limitations We have addressed the most daunting challenges encountered in the recruitment, assessment, and intervention phases of PUPS. Some challenges and solutions may not apply to trials conducted in other settings. Conclusions Overcoming challenges has required a multifaceted approach incorporating individualization, flexibility, and persistence as well as the ability to implement needed mid-course corrections. PMID:24577972

  4. Measuring Data Quality Through a Source Data Verification Audit in a Clinical Research Setting.

    PubMed

    Houston, Lauren; Probst, Yasmine; Humphries, Allison

    2015-01-01

    Health data has long been scrutinised in relation to data quality and integrity problems. Currently, no internationally accepted or "gold standard" method exists measuring data quality and error rates within datasets. We conducted a source data verification (SDV) audit on a prospective clinical trial dataset. An audit plan was applied to conduct 100% manual verification checks on a 10% random sample of participant files. A quality assurance rule was developed, whereby if >5% of data variables were incorrect a second 10% random sample would be extracted from the trial data set. Error was coded: correct, incorrect (valid or invalid), not recorded or not entered. Audit-1 had a total error of 33% and audit-2 36%. The physiological section was the only audit section to have <5% error. Data not recorded to case report forms had the greatest impact on error calculations. A significant association (p=0.00) was found between audit-1 and audit-2 and whether or not data was deemed correct or incorrect. Our study developed a straightforward method to perform a SDV audit. An audit rule was identified and error coding was implemented. Findings demonstrate that monitoring data quality by a SDV audit can identify data quality and integrity issues within clinical research settings allowing quality improvement to be made. The authors suggest this approach be implemented for future research.

  5. Women's Perceptions of Reproductive Health in Three Communities around Beirut, Lebanon

    PubMed Central

    Kaddour, Afamia; Hafez, Raghda; Zurayk, Huda

    2006-01-01

    The aim of this study was to elicit definitions of the concept of reproductive health among women in three communities around Beirut, Lebanon, as part of the reproductive health component of a larger Urban Health Study. The communities were characterised by poverty, rural-urban mobility and heterogeneous refugee and migrant populations. A random sample of 1,869 women of reproductive age completed a questionnaire, of whom a sub-sample of 201 women were randomly selected. The women's understanding of good reproductive health included three major themes, which were expressed differently in the three communities. Their understanding included good physical and mental health, and underscored the need for activities promoting health. Their ability to reproduce and raise children, practise family planning and birth spacing, and go through pregnancy and motherhood safely were central to their reproductive duties and their social status. Finally, they saw reproductive health within the context of economic status, good marital relations and strength to cope with their lives. These findings point to the need to situate interventions in the life course of women, their health and that of their husbands and families; the importance of reproduction not only from a health services point of view, but also as regards women's roles and responsibilities within marriage and their families; and taking account of the harsh socio-economic conditions in their communities. A 2005 Reproductive Health Matters. All rights reserved. PMID:16035595

  6. Women's perceptions of reproductive health in three communities around Beirut, Lebanon.

    PubMed

    Kaddour, Afamia; Hafez, Raghda; Zurayk, Huda

    2005-05-01

    The aim of this study was to elicit definitions of the concept of reproductive health among women in three communities around Beirut, Lebanon, as part of the reproductive health component of a larger Urban Health Study. The communities were characterised by poverty, rural-urban mobility and heterogeneous refugee and migrant populations. A random sample of 1,869 women of reproductive age completed a questionnaire, of whom a sub-sample of 201 women were randomly selected. The women's understanding of good reproductive health included three major themes, which were expressed differently in the three communities. Their understanding included good physical and mental health, and underscored the need for activities promoting health. Their ability to reproduce and raise children, practise family planning and birth spacing, and go through pregnancy and motherhood safely were central to their reproductive duties and their social status. Finally, they saw reproductive health within the context of economic status, good marital relations and strength to cope with their lives. These findings point to the need to situate interventions in the life course of women, their health and that of their husbands and families; the importance of reproduction not only from a health services point of view, but also as regards women's roles and responsibilities within marriage and their families; and taking account of the harsh socio-economic conditions in their communities.

  7. Effects of Communities That Care on Males' and Females' Drug Use and Delinquency 9 Years After Baseline in a Community-Randomized Trial.

    PubMed

    Oesterle, Sabrina; Hawkins, J David; Kuklinski, Margaret R; Fagan, Abigail A; Fleming, Christopher; Rhew, Isaac C; Brown, Eric C; Abbott, Robert D; Catalano, Richard F

    2015-12-01

    This study tested sustained effects of the Communities That Care (CTC) prevention system on health-risking behaviors 9 years after baseline in a community-randomized trial involving 24 towns in seven states. Earlier analyses found sustained effects on abstinence from drug use and delinquency through Grade 12 in a panel of fifth graders. At age 19, 91 % (n = 3986) of the living panel completed the survey. Data were analyzed using generalized linear mixed models. The prevalence of lifetime and current substance use and delinquency were the primary outcomes. Secondary outcomes included substance use disorders, major depression, suicidality, educational attainment, and sexual risk behaviors. CTC had a significant overall effect across lifetime measures of the primary outcomes for males, but not for females or the full sample, although lifetime abstinence from delinquency in the full sample was significantly higher in CTC communities (ARR = 1.16). Males in CTC communities also continued to show greater lifetime abstinence from cigarette smoking (ARR = 1.22). CTC did not have a sustained effect on current substance use and delinquency nor did it improve the secondary outcomes at age 19 for either gender. Communities using CTC may need to extend their prevention planning to include the high school years to sustain effects on drug use and delinquency beyond high school for both genders. ClinicalTrials.gov identifier: NCT01088542.

  8. Effects of Communities That Care on Males’ and Females’ Drug Use and Delinquency 9 Years After Baseline in a Community-Randomized Trial

    PubMed Central

    Hawkins, J. David; Kuklinski, Margaret R.; Fagan, Abigail A.; Fleming, Christopher; Rhew, Isaac C.; Brown, Eric C.; Abbott, Robert D.; Catalano, Richard F.

    2016-01-01

    This study tested sustained effects of the Communities That Care (CTC) prevention system on health-risking behaviors 9 years after baseline in a community-randomized trial involving 24 towns in seven states. Earlier analyses found sustained effects on abstinence from drug use and delinquency through Grade 12 in a panel of fifth graders. At age 19, 91 % (n = 3986) of the living panel completed the survey. Data were analyzed using generalized linear mixed models. The prevalence of lifetime and current substance use and delinquency were the primary outcomes. Secondary outcomes included substance use disorders, major depression, suicidality, educational attainment, and sexual risk behaviors. CTC had a significant overall effect across lifetime measures of the primary outcomes for males, but not for females or the full sample, although lifetime abstinence from delinquency in the full sample was significantly higher in CTC communities (ARR = 1.16). Males in CTC communities also continued to show greater lifetime abstinence from cigarette smoking (ARR = 1.22). CTC did not have a sustained effect on current substance use and delinquency nor did it improve the secondary outcomes at age 19 for either gender. Communities using CTC may need to extend their prevention planning to include the high school years to sustain effects on drug use and delinquency beyond high school for both genders. PMID:26377418

  9. Factors important in the purchase of partnership long-term care insurance.

    PubMed

    McCall, N; Mangle, S; Bauer, E; Knickman, J

    1998-06-01

    To understand the factors important in the purchase of long-term care insurance through the Robert Wood Johnson Foundation Partnership for Long-Term Care. Information on the Partnership programs, telephone surveys, data on Partnership purchasers, and random sample frames. Logistic regression analysis is used to examine characteristics associated with the purchase of a Partnership insurance policy. Independent variables are health status, demographic and financial characteristics, knowledge, and attitudes. A telephone survey of Partnership purchasers and a random sample of the population in each Partnership state were conducted. Survey questions included health status, opinions about long-term care and long-term care insurance, financial planning, demographic characteristics, and income and assets. Important in the purchase of a Partnership policy were variables associated with education and knowledge about long-term care. Other important factors include attitudes and health status. Partnership purchase is associated with higher income and asset levels up to a point, with the effect plateauing and decreasing at the highest income and asset levels. Improved education and knowledge are important in increasing long-term care insurance purchase. Attitudes about having a caregiver, and about the government's role in paying for long-term care as well as the potential purchaser's willingness to consider nursing home care affect policy purchase. Also associated with Partnership policy purchase are better health and middle income and asset levels.

  10. A randomized community trial of enhanced family planning outreach in Rakai, Uganda.

    PubMed

    Lutalo, Tom; Kigozi, Godfrey; Kimera, Edward; Serwadda, David; Wawer, Maria J; Zabin, Laurie Schwab; Gray, Ronald H

    2010-03-01

    A randomized community trial of a family planning outreach program was conducted in Rakai District, Uganda. Five communities received standard services; six intervention communities received additional family planning information, counseling, and contraceptive methods from government service providers and community-based volunteer agents using social marketing and other strategies. Condom use was promoted in all of the communities. The community-based family planning outreach program was implemented in two phases--1999-2000 (early) and 2001(late)--and its impact was evaluated by means of population surveys in 2002-03. At follow-up, hormonal contraceptive prevalence was 23 percent in the intervention communities, compared with 20 percent in the control communities. The differential was greater in the early-intervention communities than the late-intervention communities. Pregnancy rates at follow-up were 15 percent in the control and 13 percent in the intervention communities. No differentials in condom use were found between study arms. Family planning outreach via social marketing can significantly increase hormonal contraceptive use and decrease pregnancy rates, but the impact of this outreach program was modest.

  11. Physicians' Views on Advance Care Planning and End-of-Life Care Conversations.

    PubMed

    Fulmer, Terry; Escobedo, Marcus; Berman, Amy; Koren, Mary Jane; Hernández, Sandra; Hult, Angela

    2018-05-23

    To evaluate physicians' views on advance care planning, goals of care, and end-of-life conversations. Random sample telephone survey. United States. Physicians (primary care specialists; pulmonology, cardiology, oncology subspecialists) actively practicing medicine and regularly seeing patients aged 65 and older (N=736; 81% male, 75% white, 66% aged ≥50. A 37-item telephone survey constructed by a professional polling group with national expert oversight measured attitudes and perceptions of barriers and facilitators to advance care planning. Summative data are presented here. Ninety-nine percent of participants agreed that it is important to have end-of-life conversations, yet only 29% reported that they have formal training for such conversations. Those most likely to have training included younger physicians and those caring for a racially and ethnically diverse population. Patient values and preferences were the strongest motivating factors in having advance care planning conversations, with 92% of participants rating it extremely important. Ninety-five percent of participants reported that they supported a new Medicare fee-for-service benefit reimbursing advance care planning. The biggest barrier mentioned was time availability. Other barriers included not wanting a patient to give up hope and feeling uncomfortable. With more than half of physicians reporting that they feel educationally unprepared, there medical school curricula need to be strengthened to ensure readiness for end-of-life conversations. Clinician barriers need to be addressed to meet the needs of older adults and families. Policies that focus on payment for quality should be evaluated at regular intervals to monitor their effect on advance care planning. © 2018, Copyright the Authors Journal compilation © 2018, The American Geriatrics Society.

  12. Goal conflict, goal facilitation, and health professionals' provision of physical activity advice in primary care: an exploratory prospective study.

    PubMed

    Presseau, Justin; Francis, Jill J; Campbell, Neil C; Sniehotta, Falko F

    2011-07-15

    The theory of planned behaviour has well-evidenced utility in predicting health professional behaviour, but focuses on a single behaviour isolated from the numerous potentially conflicting and facilitating goal-directed behaviours performed alongside. Goal conflict and goal facilitation may influence whether health professionals engage in guideline-recommended behaviours, and may supplement the predictive power of the theory of planned behaviour. We hypothesised that goal facilitation and goal conflict contribute to predicting primary care health professionals' provision of physical activity advice to patients with hypertension, over and above predictors of behaviour from the theory of planned behaviour. Using a prospective predictive design, at baseline we invited a random sample of 606 primary care health professionals from all primary care practices in NHS Grampian and NHS Tayside (Scotland) to complete postal questionnaires. Goal facilitation and goal conflict were measured alongside theory of planned behaviour constructs at baseline. At follow-up six months later, participants self-reported the number of patients, out of those seen in the preceding two weeks, to whom they provided physical activity advice. Forty-four primary care physicians and nurses completed measures at both time points (7.3% response rate). Goal facilitation and goal conflict improved the prediction of behaviour, accounting for substantial additional variance (5.8% and 8.4%, respectively) in behaviour over and above intention and perceived behavioural control. Health professionals' provision of physical activity advice in primary care can be predicted by perceptions about how their conflicting and facilitating goal-directed behaviours help and hinder giving advice, over and above theory of planned behaviour constructs. Incorporating features of multiple goal pursuit into the theory of planned behaviour may help to better understand health professional behaviour.

  13. Goal conflict, goal facilitation, and health professionals' provision of physical activity advice in primary care: An exploratory prospective study

    PubMed Central

    2011-01-01

    Background The theory of planned behaviour has well-evidenced utility in predicting health professional behaviour, but focuses on a single behaviour isolated from the numerous potentially conflicting and facilitating goal-directed behaviours performed alongside. Goal conflict and goal facilitation may influence whether health professionals engage in guideline-recommended behaviours, and may supplement the predictive power of the theory of planned behaviour. We hypothesised that goal facilitation and goal conflict contribute to predicting primary care health professionals' provision of physical activity advice to patients with hypertension, over and above predictors of behaviour from the theory of planned behaviour. Methods Using a prospective predictive design, at baseline we invited a random sample of 606 primary care health professionals from all primary care practices in NHS Grampian and NHS Tayside (Scotland) to complete postal questionnaires. Goal facilitation and goal conflict were measured alongside theory of planned behaviour constructs at baseline. At follow-up six months later, participants self-reported the number of patients, out of those seen in the preceding two weeks, to whom they provided physical activity advice. Results Forty-four primary care physicians and nurses completed measures at both time points (7.3% response rate). Goal facilitation and goal conflict improved the prediction of behaviour, accounting for substantial additional variance (5.8% and 8.4%, respectively) in behaviour over and above intention and perceived behavioural control. Conclusions Health professionals' provision of physical activity advice in primary care can be predicted by perceptions about how their conflicting and facilitating goal-directed behaviours help and hinder giving advice, over and above theory of planned behaviour constructs. Incorporating features of multiple goal pursuit into the theory of planned behaviour may help to better understand health professional behaviour. PMID:21762486

  14. 40 CFR 761.130 - Sampling requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... sampling scheme and the guidance document are available on EPA's PCB Web site at http://www.epa.gov/pcb, or... § 761.125(c) (2) through (4). Using its best engineering judgment, EPA may sample a statistically valid random or grid sampling technique, or both. When using engineering judgment or random “grab” samples, EPA...

  15. 40 CFR 761.130 - Sampling requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... sampling scheme and the guidance document are available on EPA's PCB Web site at http://www.epa.gov/pcb, or... § 761.125(c) (2) through (4). Using its best engineering judgment, EPA may sample a statistically valid random or grid sampling technique, or both. When using engineering judgment or random “grab” samples, EPA...

  16. Misrepresenting random sampling? A systematic review of research papers in the Journal of Advanced Nursing.

    PubMed

    Williamson, Graham R

    2003-11-01

    This paper discusses the theoretical limitations of the use of random sampling and probability theory in the production of a significance level (or P-value) in nursing research. Potential alternatives, in the form of randomization tests, are proposed. Research papers in nursing, medicine and psychology frequently misrepresent their statistical findings, as the P-values reported assume random sampling. In this systematic review of studies published between January 1995 and June 2002 in the Journal of Advanced Nursing, 89 (68%) studies broke this assumption because they used convenience samples or entire populations. As a result, some of the findings may be questionable. The key ideas of random sampling and probability theory for statistical testing (for generating a P-value) are outlined. The result of a systematic review of research papers published in the Journal of Advanced Nursing is then presented, showing how frequently random sampling appears to have been misrepresented. Useful alternative techniques that might overcome these limitations are then discussed. REVIEW LIMITATIONS: This review is limited in scope because it is applied to one journal, and so the findings cannot be generalized to other nursing journals or to nursing research in general. However, it is possible that other nursing journals are also publishing research articles based on the misrepresentation of random sampling. The review is also limited because in several of the articles the sampling method was not completely clearly stated, and in this circumstance a judgment has been made as to the sampling method employed, based on the indications given by author(s). Quantitative researchers in nursing should be very careful that the statistical techniques they use are appropriate for the design and sampling methods of their studies. If the techniques they employ are not appropriate, they run the risk of misinterpreting findings by using inappropriate, unrepresentative and biased samples.

  17. The SALOME study: recruitment experiences in a clinical trial offering injectable diacetylmorphine and hydromorphone for opioid dependency.

    PubMed

    Oviedo-Joekes, Eugenia; Marchand, Kirsten; Lock, Kurt; MacDonald, Scott; Guh, Daphne; Schechter, Martin T

    2015-01-26

    The Study to Assess Long-term Opioid Medication Effectiveness (SALOME) is a two-stage phase III, single site (Vancouver, Canada), randomized, double blind controlled trial designed to test if hydromorphone is as effective as diacetylmorphine for the treatment of long-term illicit opioid injection. Recruiting participants for clinical trials continues to be a challenge in medical and addiction research, with many studies not being able to reach the planned sample size in a timely manner. The aim of this study is to describe the recruitment strategies in SALOME, which offered appealing treatments but had limited clinic capacity and no guaranteed post-trial continuation of the treatments. SALOME included chronic opioid-dependent, current illicit injection opioid users who had at least one previous episode of opioid maintenance treatment. Regulatory approvals were received in June 2011 and recruitment strategies were implemented over the next 5 months. Recruitment strategies included ongoing open communication with the community, a consistent and accessible team and participant-centered screening. All applicants completed a pre-screening checklist to assess prerequisites. Applicants meeting these prerequisites were later contacted to commence the screening process. A total of 598 applications were received over the two-year recruitment period; 130 were received on the first day of recruitment. Of these applicants, 485 met prerequisites; however, many could not be found or were not reached before recruitment ended. For the 253 candidates who initiated the screening process, the average time lapse between application and screening date was 8.3 months (standard deviation [SD] = 4.44) and for the 202 randomized to the study, the average processing time from initial screen to randomization was 25.9 days (SD = 37.48; Median = 15.0). As in prior trials offering injectable diacetylmorphine within a supervised model, recruiting participants for this study took longer than planned. The recruitment challenges overcome in SALOME were due to the high number of applicants compared with the limited number that could be randomized and treated. Our study emphasizes the value of integrating these strategies into clinical addiction research to overcome study-specific barriers. ClinicalTrials.gov: NCT01447212.

  18. A randomized controlled trial of pre-conception treatment for periodontal disease to improve periodontal status during pregnancy and birth outcomes.

    PubMed

    Jiang, Hong; Xiong, Xu; Su, Yi; Zhang, Yiming; Wu, Hongqiao; Jiang, Zhijun; Qian, Xu

    2013-12-09

    Evidence has suggested that periodontal disease is associated with an increased risk of various adverse pregnancy and birth outcomes. However, several large clinical randomized controlled trials failed to demonstrate periodontal therapy during pregnancy reduced the incidence of adverse pregnancy and birth outcomes. It has been suggested that the pre-conception period may be an optimal period for periodontal disease treatment rather than during pregnancy. To date, no randomized controlled trial (RCT) has examined if treating periodontal disease before pregnancy reduces adverse birth outcomes. This study aims to examine if the pre-conception treatment of periodontal disease will lead to improved periodontal status during late pregnancy and subsequent birth outcomes. A sample of 470 (235 in each arm of the study) pre-conception women who plan to conceive within one year and with periodontal disease will be recruited for the study. All participants will be randomly allocated to the intervention or control group. The intervention group will receive free therapy including dental scaling and root planning (the standard therapy), supragingival prophylaxis, and oral hygiene education. The control group will only receive supragingival prophylaxis and oral hygiene education. Women will be followed throughout their pregnancy and then to childbirth. The main outcomes include periodontal disease status in late pregnancy and birth outcomes measured such as mean birth weight (grams), and mean gestational age (weeks). Periodontal disease will be diagnosed through a dental examination by measuring probing depth, clinical attachment loss and percentage of bleeding on probing (BOP) between gestational age of 32 and 36 weeks. Local and systemic inflammatory mediators are also included as main outcomes. This will be the first RCT to test whether treating periodontal disease among pre-conception women reduces periodontal disease during pregnancy and prevents adverse birth outcomes. If the effect of pre-pregnancy periodontal treatment is confirmed, this intervention could be recommended for application in low- or middle-income countries to improve both oral health and maternal and child health. This trial is registered with Chinese Clinical Trial Registry (ChiCTR): ChiCTR-TRC-12001913.

  19. [Prevalence and spatial distribution of trachoma among schoolchildren in Botucatu, São Paulo - Brazil].

    PubMed

    Schellini, Silvana Artioli; Lavezzo, Marcelo Mendes; Ferraz, Lucieni Barbarini; Olbrich Neto, Jaime; Medina, Norma Hellen; Padovani, Carlos Roberto

    2010-01-01

    To assess the prevalence of trachoma in schoolchildren of Botucatu/ SP-Brazil and its spatial distribution. Cross-sectional study in children aged from 7 to 14 years, who attended elementary schools in Botucatu/SP in November/2005. The sample size was estimated in 2,092 children, considering the 11.2% historic prevalence of trachoma, accepting an estimation error of 10% and confidence level of 95%. The sample was random, weighted and increased by 20%, because of the possible occurrence of losses. The total number of children examined was 2,692. The diagnosis was clinical, based on WHO guidelines. For the evaluation of spatial data, the CartaLinx program (v1.2) was used, and the school demand sectors digitized according to the planning divisions of the Department of Education. The data were statistically analyzed, and the analysis of the spatial structure of events calculated using the Geode program. The prevalence of trachoma in schoolchildren of Botucatu was 2.9% and there were cases of follicular trachoma. The exploratory spatial analysis failed to reject the null hypothesis of randomness (R= -0.45, p>0.05), with no significant demand sectors. The analysis for the Thiessen polygons also showed that the overall pattern was random (I= -0.07, p=0.49). However, local indicators pointed to a group of low-low type for a polygon to the north of the urban area. The prevalence of trachoma in schoolchildren in Botucatu was 2.9%. The analysis of the spatial distribution did not reveal areas of greater clustering of cases. Although the overall pattern of the disease does not reproduce the socio-economic conditions of the population, the lower prevalence of trachoma was found in areas of lower social vulnerability.

  20. Epidemiology of bovine brucellosis in Costa Rica: Lessons learned from failures in the control of the disease

    PubMed Central

    Hernández-Mora, Gabriela; Ruiz-Villalobos, Nazareth; Bonilla-Montoya, Roberto; Romero-Zúniga, Juan-José; Jiménez-Arias, Julio; González-Barrientos, Rocío; Barquero-Calvo, Elías; Chacón-Díaz, Carlos; Rojas, Norman; Chaves-Olarte, Esteban; Guzmán-Verri, Caterina

    2017-01-01

    Brucellosis, caused by Brucella abortus is a major disease of cattle and a zoonosis. In order to estimate the bovine brucellosis prevalence in Costa Rica (CR), a total 765 herds (13078 bovines) from six regions of CR were randomly sampled during 2012–2013. A non-random sample of 7907 herds (532199 bovines) of the six regions, arriving for diagnoses during 2014–2016 to the Costa Rican Animal Health Service was also studied. The prevalence estimated by Rose Bengal test (RBT) ranged from 10.5%-11.4%; alternatively, the prevalence estimated by testing the RBT positives in iELISA, ranged from 4.1%-6.0%, respectively. However, cattle in CR are not vaccinated with B. abortus S19 but with RB51 (vaccination coverage close to 11%), and under these conditions the RBT displays 99% specificity and 99% sensitivity. Therefore, the RBT herd depicted in the random analysis stands as a feasible assessment and then, the recommended value in case of planning an eradication program in CR. Studies of three decades reveled that bovine brucellosis prevalence has increased in CR. B. abortus was identified by biochemical and molecular studies as the etiological agent of bovine brucellosis. Multiple locus variable-number tandem repeat analysis-16 revealed four B. abortus clusters. Cluster one and three are intertwined with isolates from other countries, while clusters two and four have only representatives from CR. Cluster one is widely distributed in all regions of the country and may be the primary B. abortus source. The other clusters seem to be restricted to specific areas in CR. The implications of our findings, in relation to the control of the disease in CR, are critically discussed. PMID:28797045

  1. Epidemiology of bovine brucellosis in Costa Rica: Lessons learned from failures in the control of the disease.

    PubMed

    Hernández-Mora, Gabriela; Ruiz-Villalobos, Nazareth; Bonilla-Montoya, Roberto; Romero-Zúniga, Juan-José; Jiménez-Arias, Julio; González-Barrientos, Rocío; Barquero-Calvo, Elías; Chacón-Díaz, Carlos; Rojas, Norman; Chaves-Olarte, Esteban; Guzmán-Verri, Caterina; Moreno, Edgardo

    2017-01-01

    Brucellosis, caused by Brucella abortus is a major disease of cattle and a zoonosis. In order to estimate the bovine brucellosis prevalence in Costa Rica (CR), a total 765 herds (13078 bovines) from six regions of CR were randomly sampled during 2012-2013. A non-random sample of 7907 herds (532199 bovines) of the six regions, arriving for diagnoses during 2014-2016 to the Costa Rican Animal Health Service was also studied. The prevalence estimated by Rose Bengal test (RBT) ranged from 10.5%-11.4%; alternatively, the prevalence estimated by testing the RBT positives in iELISA, ranged from 4.1%-6.0%, respectively. However, cattle in CR are not vaccinated with B. abortus S19 but with RB51 (vaccination coverage close to 11%), and under these conditions the RBT displays 99% specificity and 99% sensitivity. Therefore, the RBT herd depicted in the random analysis stands as a feasible assessment and then, the recommended value in case of planning an eradication program in CR. Studies of three decades reveled that bovine brucellosis prevalence has increased in CR. B. abortus was identified by biochemical and molecular studies as the etiological agent of bovine brucellosis. Multiple locus variable-number tandem repeat analysis-16 revealed four B. abortus clusters. Cluster one and three are intertwined with isolates from other countries, while clusters two and four have only representatives from CR. Cluster one is widely distributed in all regions of the country and may be the primary B. abortus source. The other clusters seem to be restricted to specific areas in CR. The implications of our findings, in relation to the control of the disease in CR, are critically discussed.

  2. The Expected Sample Variance of Uncorrelated Random Variables with a Common Mean and Some Applications in Unbalanced Random Effects Models

    ERIC Educational Resources Information Center

    Vardeman, Stephen B.; Wendelberger, Joanne R.

    2005-01-01

    There is a little-known but very simple generalization of the standard result that for uncorrelated random variables with common mean [mu] and variance [sigma][superscript 2], the expected value of the sample variance is [sigma][superscript 2]. The generalization justifies the use of the usual standard error of the sample mean in possibly…

  3. A post hoc evaluation of a sample size re-estimation in the Secondary Prevention of Small Subcortical Strokes study.

    PubMed

    McClure, Leslie A; Szychowski, Jeff M; Benavente, Oscar; Hart, Robert G; Coffey, Christopher S

    2016-10-01

    The use of adaptive designs has been increasing in randomized clinical trials. Sample size re-estimation is a type of adaptation in which nuisance parameters are estimated at an interim point in the trial and the sample size re-computed based on these estimates. The Secondary Prevention of Small Subcortical Strokes study was a randomized clinical trial assessing the impact of single- versus dual-antiplatelet therapy and control of systolic blood pressure to a higher (130-149 mmHg) versus lower (<130 mmHg) target on recurrent stroke risk in a two-by-two factorial design. A sample size re-estimation was performed during the Secondary Prevention of Small Subcortical Strokes study resulting in an increase from the planned sample size of 2500-3020, and we sought to determine the impact of the sample size re-estimation on the study results. We assessed the results of the primary efficacy and safety analyses with the full 3020 patients and compared them to the results that would have been observed had randomization ended with 2500 patients. The primary efficacy outcome considered was recurrent stroke, and the primary safety outcomes were major bleeds and death. We computed incidence rates for the efficacy and safety outcomes and used Cox proportional hazards models to examine the hazard ratios for each of the two treatment interventions (i.e. the antiplatelet and blood pressure interventions). In the antiplatelet intervention, the hazard ratio was not materially modified by increasing the sample size, nor did the conclusions regarding the efficacy of mono versus dual-therapy change: there was no difference in the effect of dual- versus monotherapy on the risk of recurrent stroke hazard ratios (n = 3020 HR (95% confidence interval): 0.92 (0.72, 1.2), p = 0.48; n = 2500 HR (95% confidence interval): 1.0 (0.78, 1.3), p = 0.85). With respect to the blood pressure intervention, increasing the sample size resulted in less certainty in the results, as the hazard ratio for higher versus lower systolic blood pressure target approached, but did not achieve, statistical significance with the larger sample (n = 3020 HR (95% confidence interval): 0.81 (0.63, 1.0), p = 0.089; n = 2500 HR (95% confidence interval): 0.89 (0.68, 1.17), p = 0.40). The results from the safety analyses were similar to 3020 and 2500 patients for both study interventions. Other trial-related factors, such as contracts, finances, and study management, were impacted as well. Adaptive designs can have benefits in randomized clinical trials, but do not always result in significant findings. The impact of adaptive designs should be measured in terms of both trial results, as well as practical issues related to trial management. More post hoc analyses of study adaptations will lead to better understanding of the balance between the benefits and the costs. © The Author(s) 2016.

  4. Family planning in Santiageo, Chile: the male viewpoint.

    PubMed

    Hall, M F

    1971-07-01

    To obtain the male viewpoint toward family planning in the Chilean population, 561 men (aged 18-54) in Santiago from upper, middle, and lower socioeconomic levels were interviewed on their birth control attitudes and practices and compared with a random probability sample of 240 men from a nearby rural village. Tabulation of the interviews showed that a majority of both unmarried and married men identified themselves as active participants in birth control discussions. Younger husbands tended to have had more experience with contraception than older husbands, and respondents in higher socioeconomic levels showed a greater use of contraception (75%) than men in the lower class or village sample (35%). 23% of those in the village sample who did not use contraception cited reasons such as lack of knowledge and money or fear of harmful effects, while only 2% of the upper class in the urban sample cited such reasons. Approval of abortion for their wives was expressed by around 40% of all respondents. Approval of abortion in general ranged from 81% in cases of probable fetal deformity to 31% in single girls. Questions on sexual relations revealed that the median age for the first sexual intercourse was 16 years. 91% of the unmarried men were sexually active at a median frequence of once every 2 weeks, and contraception, if used, was most frequently oral or male devices. Among married men, sexual relations occurred at a median frequency of once every 4 days, with contraception, if used, most likely being an intrauterine device. All of the respondents tended to favor dissemination of contraceptive information more readily to men than women. Approval of providing this information to single girls was directly related to economic status. The schools were readily accepted as a forum for contraceptive discussion. The father was by far the preferred principal source of information for a son (44%) rather than friends (6%), but the respondents themselves got their information from friends (41%) rather than their fathers (2%). Including single and married men in family planning counseling programs may increase contraceptive use and lower the abortion rate.

  5. Surveillance plan for the early detection of H5N1 highly pathogenic avian influenza virus in migratory birds in the United States: surveillance year 2009

    USGS Publications Warehouse

    Brand, Christopher J.

    2009-01-01

    Executive Summary: This Surveillance Plan (Plan) describes plans for conducting surveillance of wild birds in the United States and its Territories and Freely-Associated States to provide for early detection of the introduction of the H5N1 Highly Pathogenic Avian Influenza (HPAI) subtype of the influenza A virus by migratory birds during the 2009 surveillance year, spanning the period of April 1, 2009 - March 31, 2010. The Plan represents a continuation of surveillance efforts begun in 2006 under the Interagency Strategic Plan for the Early Detection of H5N1 Highly Pathogenic Avian Influenza in Wild Migratory Birds (U.S. Department of Agriculture and U.S. Department of the Interior, 2006). The Plan sets forth sampling plans by: region, target species or species groups to be sampled, locations of sampling, sample sizes, and sampling approaches and methods. This Plan will be reviewed annually and modified as appropriate for subsequent surveillance years based on evaluation of information from previous years of surveillance, changing patterns and threats of H5N1 HPAI, and changes in funding availability for avian influenza surveillance. Specific sampling strategies will be developed accordingly within each of six regions, defined here as Alaska, Hawaiian/Pacific Islands, Lower Pacific Flyway (Washington, Oregon, California, Idaho, Nevada, Arizona), Central Flyway, Mississippi Flyway, and Atlantic Flyway.

  6. [Suicidal behaviour among prisoners: prevalence and association with psychological distress in Flemish prisons].

    PubMed

    Favril, L; Vander Laenen, F; Audenaert, K

    Internationally, the prevalence of suicidal behaviour (suicidal ideation, suicide plan and attempted suicide) is significantly elevated among prisoners compared to the community at large. To estimate the prevalence of suicidal behaviour among prisoners in the Flanders region of Belgium, to identify differences according to gender and custodial status, and to examine the association of recent suicidal ideation and suicide plan with psychological distress. We performed a cross-sectional survey using a representative sample of 1,326 prisoners, randomly selected from 15 Flemish prisons. During their lifetime, an estimated 44.4% of prisoners in Flanders reported suicidal ideation, 30.2% made a suicide plan, and one-fifth (21.8%) attempted suicide at least once. Past-year suicidal ideation in prison was endorsed by one-fourth (24.9%) of all prisoners, and 14.3% made a recent suicidal plan during their current incarceration. Approximately one in ten prisoners (9.5%) attempted suicide while in prison. Recent suicidal ideation and suicide plan were significantly associated with high levels of psychological distress. Generally, female prisoners reported significant higher levels of suicidal behaviour than men, while differences according to custodial status were less unequivocal. Corroborating international research findings, high rates of suicidal behaviour were identified among prisoners in Flanders, compared to the general population. Not only is suicidal behaviour a significant risk factor for suicide, it is also important in its own right as an indicator of profound psychological distress. Suicidal behaviour should therefore be an important target for prevention and intervention in this at-risk population.

  7. 7 CFR 43.106 - Choosing AQL's and sampling plans.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Choosing AQL's and sampling plans. 43.106 Section 43.106 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS STANDARDS FOR SAMPLING PLANS...

  8. A Simulation Approach to Assessing Sampling Strategies for Insect Pests: An Example with the Balsam Gall Midge

    PubMed Central

    Carleton, R. Drew; Heard, Stephen B.; Silk, Peter J.

    2013-01-01

    Estimation of pest density is a basic requirement for integrated pest management in agriculture and forestry, and efficiency in density estimation is a common goal. Sequential sampling techniques promise efficient sampling, but their application can involve cumbersome mathematics and/or intensive warm-up sampling when pests have complex within- or between-site distributions. We provide tools for assessing the efficiency of sequential sampling and of alternative, simpler sampling plans, using computer simulation with “pre-sampling” data. We illustrate our approach using data for balsam gall midge (Paradiplosis tumifex) attack in Christmas tree farms. Paradiplosis tumifex proved recalcitrant to sequential sampling techniques. Midge distributions could not be fit by a common negative binomial distribution across sites. Local parameterization, using warm-up samples to estimate the clumping parameter k for each site, performed poorly: k estimates were unreliable even for samples of n∼100 trees. These methods were further confounded by significant within-site spatial autocorrelation. Much simpler sampling schemes, involving random or belt-transect sampling to preset sample sizes, were effective and efficient for P. tumifex. Sampling via belt transects (through the longest dimension of a stand) was the most efficient, with sample means converging on true mean density for sample sizes of n∼25–40 trees. Pre-sampling and simulation techniques provide a simple method for assessing sampling strategies for estimating insect infestation. We suspect that many pests will resemble P. tumifex in challenging the assumptions of sequential sampling methods. Our software will allow practitioners to optimize sampling strategies before they are brought to real-world applications, while potentially avoiding the need for the cumbersome calculations required for sequential sampling methods. PMID:24376556

  9. Assessment of the effect of population and diary sampling methods on estimation of school-age children exposure to fine particles.

    PubMed

    Che, W W; Frey, H Christopher; Lau, Alexis K H

    2014-12-01

    Population and diary sampling methods are employed in exposure models to sample simulated individuals and their daily activity on each simulation day. Different sampling methods may lead to variations in estimated human exposure. In this study, two population sampling methods (stratified-random and random-random) and three diary sampling methods (random resampling, diversity and autocorrelation, and Markov-chain cluster [MCC]) are evaluated. Their impacts on estimated children's exposure to ambient fine particulate matter (PM2.5 ) are quantified via case studies for children in Wake County, NC for July 2002. The estimated mean daily average exposure is 12.9 μg/m(3) for simulated children using the stratified population sampling method, and 12.2 μg/m(3) using the random sampling method. These minor differences are caused by the random sampling among ages within census tracts. Among the three diary sampling methods, there are differences in the estimated number of individuals with multiple days of exposures exceeding a benchmark of concern of 25 μg/m(3) due to differences in how multiday longitudinal diaries are estimated. The MCC method is relatively more conservative. In case studies evaluated here, the MCC method led to 10% higher estimation of the number of individuals with repeated exposures exceeding the benchmark. The comparisons help to identify and contrast the capabilities of each method and to offer insight regarding implications of method choice. Exposure simulation results are robust to the two population sampling methods evaluated, and are sensitive to the choice of method for simulating longitudinal diaries, particularly when analyzing results for specific microenvironments or for exposures exceeding a benchmark of concern. © 2014 Society for Risk Analysis.

  10. A random sampling approach for robust estimation of tissue-to-plasma ratio from extremely sparse data.

    PubMed

    Chu, Hui-May; Ette, Ene I

    2005-09-02

    his study was performed to develop a new nonparametric approach for the estimation of robust tissue-to-plasma ratio from extremely sparsely sampled paired data (ie, one sample each from plasma and tissue per subject). Tissue-to-plasma ratio was estimated from paired/unpaired experimental data using independent time points approach, area under the curve (AUC) values calculated with the naïve data averaging approach, and AUC values calculated using sampling based approaches (eg, the pseudoprofile-based bootstrap [PpbB] approach and the random sampling approach [our proposed approach]). The random sampling approach involves the use of a 2-phase algorithm. The convergence of the sampling/resampling approaches was investigated, as well as the robustness of the estimates produced by different approaches. To evaluate the latter, new data sets were generated by introducing outlier(s) into the real data set. One to 2 concentration values were inflated by 10% to 40% from their original values to produce the outliers. Tissue-to-plasma ratios computed using the independent time points approach varied between 0 and 50 across time points. The ratio obtained from AUC values acquired using the naive data averaging approach was not associated with any measure of uncertainty or variability. Calculating the ratio without regard to pairing yielded poorer estimates. The random sampling and pseudoprofile-based bootstrap approaches yielded tissue-to-plasma ratios with uncertainty and variability. However, the random sampling approach, because of the 2-phase nature of its algorithm, yielded more robust estimates and required fewer replications. Therefore, a 2-phase random sampling approach is proposed for the robust estimation of tissue-to-plasma ratio from extremely sparsely sampled data.

  11. Applying the COM-B behaviour model and behaviour change wheel to develop an intervention to improve hearing-aid use in adult auditory rehabilitation.

    PubMed

    Barker, Fiona; Atkins, Lou; de Lusignan, Simon

    2016-07-01

    To introduce a psychological model of behaviour; the COM-B model and describe how this has been used in combination with the behaviour change wheel (BCW) in developing an intervention which aims to promote regular, long-term use of hearing aids by adults with acquired hearing loss. Qualitative structured interview study using the COM-B model to identify the determinants of behavioural planning on the part of audiologists; a potentially important factor in encouraging long-term hearing-aid use. Ten audiologists drawn from a random sample of five English audiology departments. The analysis suggests that behavioural planning might be more likely to occur if audiologists' psychological capability, physical and social opportunity, and reflective and automatic motivation were addressed. This analysis forms the basis of an intervention design, using the BCW, to encourage behavioural planning by audiologists and subsequent hearing-aid use by people with hearing loss. The COM-B model and BCW can be applied successfully in the context of audiology to analyse the behaviour of both people with hearing loss and professionals working with them, supplying information that is being used in intervention design. The effectiveness of the intervention will be tested in a clinical trial.

  12. Needle Steering in 3-D Via Rapid Replanning

    PubMed Central

    Patil, Sachin; Burgner, Jessica; Webster, Robert J.; Alterovitz, Ron

    2014-01-01

    Steerable needles have the potential to improve the effectiveness of needle-based clinical procedures such as biopsy and drug delivery by improving targeting accuracy and reaching previously inaccessible targets that are behind sensitive or impenetrable anatomical regions. We present a new needle steering system capable of automatically reaching targets in 3-D environments while avoiding obstacles and compensating for real-world uncertainties. Given a specification of anatomical obstacles and a clinical target (e.g., from preoperative medical images), our system plans and controls needle motion in a closed-loop fashion under sensory feedback to optimize a clinical metric. We unify planning and control using a new fast algorithm that continuously replans the needle motion. Our rapid replanning approach is enabled by an efficient sampling-based rapidly exploring random tree (RRT) planner that achieves orders-of-magnitude reduction in computation time compared with prior 3-D approaches by incorporating variable curvature kinematics and a novel distance metric for planning. Our system uses an electromagnetic tracking system to sense the state of the needle tip during the procedure. We experimentally evaluate our needle steering system using tissue phantoms and animal tissue ex vivo. We demonstrate that our rapid replanning strategy successfully guides the needle around obstacles to desired 3-D targets with an average error of less than 3 mm. PMID:25435829

  13. Statistical analysis plan of the head position in acute ischemic stroke trial pilot (HEADPOST pilot).

    PubMed

    Olavarría, Verónica V; Arima, Hisatomi; Anderson, Craig S; Brunser, Alejandro; Muñoz-Venturelli, Paula; Billot, Laurent; Lavados, Pablo M

    2017-02-01

    Background The HEADPOST Pilot is a proof-of-concept, open, prospective, multicenter, international, cluster randomized, phase IIb controlled trial, with masked outcome assessment. The trial will test if lying flat head position initiated in patients within 12 h of onset of acute ischemic stroke involving the anterior circulation increases cerebral blood flow in the middle cerebral arteries, as measured by transcranial Doppler. The study will also assess the safety and feasibility of patients lying flat for ≥24 h. The trial was conducted in centers in three countries, with ability to perform early transcranial Doppler. A feature of this trial was that patients were randomized to a certain position according to the month of admission to hospital. Objective To outline in detail the predetermined statistical analysis plan for HEADPOST Pilot study. Methods All data collected by participating researchers will be reviewed and formally assessed. Information pertaining to the baseline characteristics of patients, their process of care, and the delivery of treatments will be classified, and for each item, appropriate descriptive statistical analyses are planned with comparisons made between randomized groups. For the outcomes, statistical comparisons to be made between groups are planned and described. Results This statistical analysis plan was developed for the analysis of the results of the HEADPOST Pilot study to be transparent, available, verifiable, and predetermined before data lock. Conclusions We have developed a statistical analysis plan for the HEADPOST Pilot study which is to be followed to avoid analysis bias arising from prior knowledge of the study findings. Trial registration The study is registered under HEADPOST-Pilot, ClinicalTrials.gov Identifier NCT01706094.

  14. Accounting for length-bias and selection effects in estimating the distribution of menstrual cycle length

    PubMed Central

    Lum, Kirsten J.; Sundaram, Rajeshwari; Louis, Thomas A.

    2015-01-01

    Prospective pregnancy studies are a valuable source of longitudinal data on menstrual cycle length. However, care is needed when making inferences of such renewal processes. For example, accounting for the sampling plan is necessary for unbiased estimation of the menstrual cycle length distribution for the study population. If couples can enroll when they learn of the study as opposed to waiting for the start of a new menstrual cycle, then due to length-bias, the enrollment cycle will be stochastically larger than the general run of cycles, a typical property of prevalent cohort studies. Furthermore, the probability of enrollment can depend on the length of time since a woman’s last menstrual period (a backward recurrence time), resulting in selection effects. We focus on accounting for length-bias and selection effects in the likelihood for enrollment menstrual cycle length, using a recursive two-stage approach wherein we first estimate the probability of enrollment as a function of the backward recurrence time and then use it in a likelihood with sampling weights that account for length-bias and selection effects. To broaden the applicability of our methods, we augment our model to incorporate a couple-specific random effect and time-independent covariate. A simulation study quantifies performance for two scenarios of enrollment probability when proper account is taken of sampling plan features. In addition, we estimate the probability of enrollment and the distribution of menstrual cycle length for the study population of the Longitudinal Investigation of Fertility and the Environment Study. PMID:25027273

  15. Registered Dietitian Nutritionists' Perspectives on Integrating Food and Water System Issues into Professional Practice.

    PubMed

    Heidelberger, Lindsay; Smith, Chery; Robinson-O'Brien, Ramona; Earthman, Carrie; Robien, Kim

    2017-02-01

    Sustainable agriculture encompasses economic, environmental, and social aspects of the food system. Members of the Academy of Nutrition and Dietetics (Academy) play an important role in promoting sustainable agriculture because they work in areas where they can influence the food purchasing decisions of foodservice operations and the public. To investigate behavior of registered dietitian nutritionists (RDNs) toward incorporating sustainable agriculture principles into professional practice using the Theory of Planned Behavior. This cross-sectional study surveyed RDNs nationwide about their perspectives on incorporating sustainable agriculture issues into practice. The survey questions were based on a survey originally administered to Minnesota RDNs during 2002. The sample (N=626) was drawn from a randomly selected, national sample of Academy members. Data were analyzed using descriptive statistics, independent t tests, Pearson correlations, and stepwise regression. The sample was mostly white, female, and the average age was 45.4±12.2 years. Almost half of Academy RDNs (47%) reported incorporating environmental issues into their practice. All four Theory of Planned Behavior variables (intention, attitude, perceived behavior control, and subjective norm) were predictive of behavior to include sustainable agriculture issues into practice. Barriers to incorporating this topic into practice included lack of knowledge, ability, time, and employer support. This study found that most of the RDN respondents had heard of sustainable agriculture and nearly half reported including this topic in their professional practice. To integrate this topic into practice more consistently, RDNs need more knowledge, time, and employer support. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  16. Prevalence and characteristics of smokers at 30 Pacific Northwest colleges and universities.

    PubMed

    Thompson, Beti; Coronado, Gloria; Chen, Lu; Thompson, L Anne; Halperin, Abigail; Jaffe, Robert; McAfee, Tim; Zbikowski, Susan M

    2007-03-01

    College is an important transition period during which young adults explore tobacco use. Few large-scale studies have been conducted among college students regarding tobacco use. We initiated a study examining tobacco use in 30 colleges and universities in the Pacific Northwest. We conducted a baseline survey among students. Sample size varied by the school size; for the 14 largest schools, we drew a random sample of all students, oversampling freshmen (n approximately 750) so that we could recruit and follow a cohort to assess smoking onset during the college years. Of the remaining students, we sampled equivalent numbers of sophomores, juniors, and seniors (n = 200 each). For the 16 schools with fewer than 1,350 students, we surveyed all students. We found overall smoking rates of 17.2%. Males (18.6%) were more likely to smoke than females (16.6%; p = .03), and public college students were more likely to smoke (20.5%) than those who attended private independent schools (18.9%; p = .61), whose rates were higher than those of private religious schools (11.6%; p = .001). Overall, college students are light smokers who do not smoke every day of the month. Further, they tend not to be highly dependent on tobacco, do not consider themselves regular smokers, and plan to quit before they graduate (56.8%). School type should be considered when estimating smoking rates among 4-year college students. Data indicate that college smokers wish and plan to quit before graduation, suggesting that efforts to assist smokers in quitting during the college years may be fruitful.

  17. Married women's decision making power on family planning use and associated factors in Mizan-Aman, South Ethiopia: a cross sectional study.

    PubMed

    Belay, Abeba Daniel; Mengesha, Zelalem Birhanu; Woldegebriel, Manay Kifle; Gelaw, Yalemzewod Assefa

    2016-03-08

    Women's use of family planning service is influenced by many factors, especially by their decision making power. A woman's decision-making power, be it individual or decision made in collaboration with a partner, is the most important factor in the use of family planning in a household. The purpose of this study was to assess the impact of women's decision making power on family planning use and its associated factors. A community-based cross-sectional study was conducted on married women in the child bearing age. The women who were living in Mizan city were selected using the simple random sampling method. Trained nurses collected the data by interview, using a structured and pre-tested questioner. Bivariable and multivariable binary logistic regression analysis was used to identify the associated factors, and the odds ratio with a 95% CI was computed to assess the strength of the association. Collinearity was also assessed by looking at standard errors in the final fitted model. Overall, more than two-thirds [67.2%: 95% CI (63-71%)] of the married women were found to be more autonomous to decide family planning use. Secondary education [AOR: 9.04, 95% CI: (4.50, 18.16)], government employment [AOR: 4.84, 95% CI: (2.03, 11.52)], being wives of government employed spouses [AOR 2.71, 95% CI: (1.24, 7.97)], having husbands with college or university education [AOR: 11.29, 95% CI: (4.66, 27.35)], and being in the younger age [AOR: 0.27, 95% CI :(0.09, 0.75)] were significantly associated with women's decision-making power on family planning. In this study, women had a high decision making power in family planning use. Age category (34-44-years), formal education, and occupational status had effects on women's decision making power. Promoting parental adult education and engaging women in out of house employment is essential to improve their decision making power in using family planning.

  18. PCB Analysis Plan for Tank Archive Samples

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

    NGUYEN, D.M.

    2001-03-22

    This analysis plan specifies laboratory analysis, quality assurance/quality control (QA/QC), and data reporting requirements for analyzing polychlorinated biphenyls (PCB) concentrations in archive samples. Tank waste archive samples that are planned for PCB analysis are identified in Nguyen 2001. The tanks and samples are summarized in Table 1-1. The analytical data will be used to establish a PCB baseline inventory in Hanford tanks.

  19. STATISTICAL ANALYSIS OF TANK 5 FLOOR SAMPLE RESULTS

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

    Shine, E.

    2012-03-14

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, radionuclide, inorganic, and anion concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above their MDCs. The identification of distributions and the selection of UCL95 procedures generally followed the protocol in Singh, Armbya, and Singh [2010]. When all of an analyte's measurements lie below their MDCs, only a summary of the MDCs can be provided. The measurement results reported by SRNL are listed in Appendix A, and the results of this analysis are reported in Appendix B. The data were generally found to follow a normal distribution, and to be homogeneous across composite samples.« less

  20. Statistical Analysis of Tank 5 Floor Sample Results

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

    Shine, E. P.

    2013-01-31

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, and the radionuclide1, elemental, and chemical concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above their MDCs. The identification of distributions and the selection of UCL95 procedures generally followed the protocol in Singh, Armbya, and Singh [2010]. When all of an analyte's measurements lie below their MDCs, only a summary of the MDCs can be provided. The measurement results reported by SRNL are listed, and the results of this analysis are reported. The data were generally found to follow a normal distribution, and to be homogenous across composite samples.« less

  1. Statistical Analysis Of Tank 5 Floor Sample Results

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

    Shine, E. P.

    2012-08-01

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, and the radionuclide, elemental, and chemical concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above their MDCs. The identification of distributions and the selection of UCL95 procedures generally followed the protocol in Singh, Armbya, and Singh [2010]. When all of an analyte's measurements lie below their MDCs, only a summary of the MDCs can be provided. The measurement results reported by SRNL are listed in Appendix A, and the results of this analysis are reported in Appendix B. The data were generally found to follow a normal distribution, and to be homogenous across composite samples.« less

  2. Learning styles and teaching/learning strategy preferences: implications for educating nurses in critical care, the operating room, and infection control.

    PubMed

    Goldrick, B; Gruendemann, B; Larson, E

    1993-01-01

    To assess the learning styles and educational strategy preferences among critical care nurses, operating room nurses, and infection control practitioners. Descriptive multicenter survey using a self-report questionnaire. 108 hospitals from nine geographic regions of the United States. A random sample of 303 (93%) nurses in the three specialties responded to the survey questionnaires. The majority of participants (64%) had an abstract learning style and preferred the self-directed, discovery approach to learning. Nurses may be more abstract in their learning styles than previously reported. Experiential learning theory is an effective means of identifying nurses' learning styles and teaching/learning preferences, which can then be used to plan basic and continuing educational programs.

  3. Temari Reiki: a new hands-off approach to traditional Reiki.

    PubMed

    Townsend, Jane Stewart

    2013-04-01

    This paper encapsulates the history of Reiki, an ancient healing art, from its origins in Japan to current practice in the United States. It defines Reiki therapy and discusses the development of a new Reiki method called Temari Reiki and the use of two additional chakras. Lastly, sample clients scenarios are provided. Because of the success of Temari Reiki in my practice, recommendations include that it be integrated as therapy to augment traditional Western medicine-based patient care plans for patients with cancer, pain, stress and other disabling health issues. Also, additional research using randomized clinical trials is recommended to examine the benefits of Temari Reiki for improving patients' well-being in mind, body and spirit. © 2013 Wiley Publishing Asia Pty Ltd.

  4. Optimisation in radiotherapy. III: Stochastic optimisation algorithms and conclusions.

    PubMed

    Ebert, M

    1997-12-01

    This is the final article in a three part examination of optimisation in radiotherapy. Previous articles have established the bases and form of the radiotherapy optimisation problem, and examined certain types of optimisation algorithm, namely, those which perform some form of ordered search of the solution space (mathematical programming), and those which attempt to find the closest feasible solution to the inverse planning problem (deterministic inversion). The current paper examines algorithms which search the space of possible irradiation strategies by stochastic methods. The resulting iterative search methods move about the solution space by sampling random variates, which gradually become more constricted as the algorithm converges upon the optimal solution. This paper also discusses the implementation of optimisation in radiotherapy practice.

  5. Conic Sampling: An Efficient Method for Solving Linear and Quadratic Programming by Randomly Linking Constraints within the Interior

    PubMed Central

    Serang, Oliver

    2012-01-01

    Linear programming (LP) problems are commonly used in analysis and resource allocation, frequently surfacing as approximations to more difficult problems. Existing approaches to LP have been dominated by a small group of methods, and randomized algorithms have not enjoyed popularity in practice. This paper introduces a novel randomized method of solving LP problems by moving along the facets and within the interior of the polytope along rays randomly sampled from the polyhedral cones defined by the bounding constraints. This conic sampling method is then applied to randomly sampled LPs, and its runtime performance is shown to compare favorably to the simplex and primal affine-scaling algorithms, especially on polytopes with certain characteristics. The conic sampling method is then adapted and applied to solve a certain quadratic program, which compute a projection onto a polytope; the proposed method is shown to outperform the proprietary software Mathematica on large, sparse QP problems constructed from mass spectometry-based proteomics. PMID:22952741

  6. Clinical Effectiveness Research in Managed-care Systems: Lessons from the Pediatric Asthma Care PORT

    PubMed Central

    Finkelstein, Jonathan A; Lozano, Paula; Streiff, Kachen A; Arduino, Kelly E; Sisk, Cynthia A; Wagner, Edward H; Weiss, Kevin B; Inui, Thomas S

    2002-01-01

    Objective To highlight the unique challenges of evaluative research on practice behavior change in the “real world” settings of contemporary managed-care organizations, using the experience of the Pediatric Asthma Care PORT (Patient Outcomes Research Team). Study Setting The Pediatric Asthma Care PORT is a five-year initiative funded by the Agency for Healthcare Research and Quality to study strategies for asthma care improvement in three managed-care plans in Chicago, Seattle, and Boston. At its core is a randomized trial of two care improvement strategies compared with usual care: (1) a targeted physician education program using practice based Peer Leaders (PL) as change agents, (2) adding to the PL intervention a “Planned Asthma Care Intervention” incorporating joint “asthma check-ups” by nurse-physician teams. During the trial, each of the participating organizations viewed asthma care improvement as an immediate priority and had their own corporate improvement programs underway. Data Collection Investigators at each health plan described the organizational and implementation challenges in conducting the PAC PORT randomized trial. These experiences were reviewed for common themes and “lessons” that might be useful to investigators planning interventional research in similar care-delivery settings. Conclusions Randomized trials in “real world” settings represent the most robust design available to test care improvement strategies. In complex, rapidly changing managed-care organizations, blinding is not feasible, corporate initiatives may complicate implementation, and the assumption that a “usual care” arm will be static is highly likely to be mistaken. Investigators must be prepared to use innovative strategies to maintain the integrity of the study design, including: continuous improvement within the intervention arms, comanagement by researchers and health plan managers of condition-related quality improvement initiatives, procedures for avoiding respondent burden in health plan enrollees, and anticipation and minimization of risks from experimental arm contamination and major organizational change. With attention to these delivery system issues, as well as the usual design features of randomized trials, we believe managed-care organizations can serve as important laboratories to test care improvement strategies. PMID:12132605

  7. Natural cavities used by wood ducks in north-central Minnesota

    USGS Publications Warehouse

    Gilmer, D.S.; Ball, I.J.; Cowardin, L.M.; Mathisen, J.

    1978-01-01

    Radio telemetry was used to locate 31 wood duck (Aix sponsa) nest cavity sites in 16 forest stands. Stands were of 2 types: (1) mature (mean = 107 years) northern hardwoods (10 nest sites), and (2) mature (mean = 68 years) quaking aspen (Populus tremuloides) (21 nest sites). Aspen was the most important cavity-producing tree used by wood ducks and accounted for 57 percent of 28 cavities inspected. In stands used by wood ducks, the average density of suitable cavities was about 4 per hectare. Trees containing nests were closer to water areas (P < 0.05) and the nearest forest canopy openings (P < 0.01) than was a random sample of trees from the same stands. A significant (P < 0.005) relationship existed between the orientation of the cavity entrance and the nearest canopy opening. Potential wood duck cavities usually were clustered within a stand rather than randomly distributed. Selection of trees by woodpeckers for nest hole construction probably influenced the availability of cavities used by wood ducks. A plan for managing forests to benefit wood ducks and other wildlife dependent on old-growth timber is discussed.

  8. Sources of contraceptive commodities for users in Nigeria.

    PubMed

    Oye-Adeniran, Boniface A; Adewole, Isaac F; Umoh, Augustine V; Oladokun, Adesina; Gbadegesin, Abidoye; Odeyemi, Kofo A; Ekanem, Ekanem E

    2005-11-01

    Understanding the sources of contraceptive commodities is an important aspect of the delivery of family planning services and is required by planning programme managers for strategic planning purposes. Findings from the 2003 Nigeria Demographic and Health Survey have previously showed that the private sector was the most frequently reported source of contraceptive supply, providing contraception to two and a half times as many women as the public sector. We conducted a community-based study to examine further the sources of contraceptive commodity for users in Nigeria with a view to identifying their preferences for distribution centres. This information would be useful to improve commodity distribution and to build the necessary capacity for satisfactory delivery of contraceptives. A multi-stage random sampling technique was used. A state was randomly selected to represent each of the four health zones in Nigeria. Two local government areas (LGAs) were then selected representing both urban and rural areas. Ten enumeration areas were subsequently selected from each LGA. Of the 2,001 respondents aged 15-49 years, 1,647 (82.3%) were sexually active, out of which 244 were found to be using contraceptive methods at the time of the study, giving a contraceptive prevalence of 14.8%. The commonest source of information on contraceptives was through friends (34%), followed by the radio (11.5%) and husbands (10.2%). Most respondents procured their contraceptives from chemist/patent medicine shops (19.7%), while only 0.8% obtained them from designated family planning clinics. The younger groups in this study (15-24 years), single people, Catholics, and Muslims, showed a greater preference for chemist/patent medicine shops for their sources of contraceptives. The older groups and married respondents, however, made use of government and private hospitals to obtain their contraceptives. Strategies to increase contraceptive use must take into consideration these identified sources of contraceptives with a view to enhancing the quality, quantity, and variety of methods available, and to building capacity for effective service delivery. There is also a need to encourage the establishment of adolescent-friendly clinics where young people can go for counselling and obtain contraceptives of their choice, including emergency contraceptive pills.

  9. Sources of Contraceptive Commodities for Users in Nigeria

    PubMed Central

    Oye-Adeniran, Boniface A; Adewole, Isaac F; Umoh, Augustine V; Oladokun, Adesina; Gbadegesin, Abidoye; Odeyemi, Kofo A; Ekanem, Ekanem E

    2005-01-01

    Background Understanding the sources of contraceptive commodities is an important aspect of the delivery of family planning services and is required by planning programme managers for strategic planning purposes. Findings from the 2003 Nigeria Demographic and Health Survey have previously showed that the private sector was the most frequently reported source of contraceptive supply, providing contraception to two and a half times as many women as the public sector. We conducted a community-based study to examine further the sources of contraceptive commodity for users in Nigeria with a view to identifying their preferences for distribution centres. This information would be useful to improve commodity distribution and to build the necessary capacity for satisfactory delivery of contraceptives. Methods and Findings A multi-stage random sampling technique was used. A state was randomly selected to represent each of the four health zones in Nigeria. Two local government areas (LGAs) were then selected representing both urban and rural areas. Ten enumeration areas were subsequently selected from each LGA. Of the 2,001 respondents aged 15–49 years, 1,647 (82.3%) were sexually active, out of which 244 were found to be using contraceptive methods at the time of the study, giving a contraceptive prevalence of 14.8%. The commonest source of information on contraceptives was through friends (34%), followed by the radio (11.5%) and husbands (10.2%). Most respondents procured their contraceptives from chemist/patent medicine shops (19.7%), while only 0.8% obtained them from designated family planning clinics. The younger groups in this study (15–24 years), single people, Catholics, and Muslims, showed a greater preference for chemist/patent medicine shops for their sources of contraceptives. The older groups and married respondents, however, made use of government and private hospitals to obtain their contraceptives. Conclusion Strategies to increase contraceptive use must take into consideration these identified sources of contraceptives with a view to enhancing the quality, quantity, and variety of methods available, and to building capacity for effective service delivery. There is also a need to encourage the establishment of adolescent-friendly clinics where young people can go for counselling and obtain contraceptives of their choice, including emergency contraceptive pills. PMID:16218768

  10. Point-Sampling and Line-Sampling Probability Theory, Geometric Implications, Synthesis

    Treesearch

    L.R. Grosenbaugh

    1958-01-01

    Foresters concerned with measuring tree populations on definite areas have long employed two well-known methods of representative sampling. In list or enumerative sampling the entire tree population is tallied with a known proportion being randomly selected and measured for volume or other variables. In area sampling all trees on randomly located plots or strips...

  11. Randomized branch sampling

    Treesearch

    Harry T. Valentine

    2002-01-01

    Randomized branch sampling (RBS) is a special application of multistage probability sampling (see Sampling, environmental), which was developed originally by Jessen [3] to estimate fruit counts on individual orchard trees. In general, the method can be used to obtain estimates of many different attributes of trees or other branched plants. The usual objective of RBS is...

  12. Deterministic multidimensional nonuniform gap sampling.

    PubMed

    Worley, Bradley; Powers, Robert

    2015-12-01

    Born from empirical observations in nonuniformly sampled multidimensional NMR data relating to gaps between sampled points, the Poisson-gap sampling method has enjoyed widespread use in biomolecular NMR. While the majority of nonuniform sampling schemes are fully randomly drawn from probability densities that vary over a Nyquist grid, the Poisson-gap scheme employs constrained random deviates to minimize the gaps between sampled grid points. We describe a deterministic gap sampling method, based on the average behavior of Poisson-gap sampling, which performs comparably to its random counterpart with the additional benefit of completely deterministic behavior. We also introduce a general algorithm for multidimensional nonuniform sampling based on a gap equation, and apply it to yield a deterministic sampling scheme that combines burst-mode sampling features with those of Poisson-gap schemes. Finally, we derive a relationship between stochastic gap equations and the expectation value of their sampling probability densities. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Coosa River Storage Annex, Talladega, Alabama Environmental Investigation, Final Management and Resources Utilization Plan

    DTIC Science & Technology

    1991-02-01

    to adequately assess the health and environmental risks associated with the closure and transfer of the Annex forI other use; and 3) identification of...1990); Draft Final Technical Plan, Draft Final Sampling Design Plan and Draft Final Health and Safety Plan, USATHAMA, June 1990. 2.1.2 Draft Final...Final Technical Plan, Sampling Design Plan and Health and Safety Plan) supplied by USATHAMA. The estimate may be revised, with USATHAMA approval, as

  14. Observational studies of patients in the emergency department: a comparison of 4 sampling methods.

    PubMed

    Valley, Morgan A; Heard, Kennon J; Ginde, Adit A; Lezotte, Dennis C; Lowenstein, Steven R

    2012-08-01

    We evaluate the ability of 4 sampling methods to generate representative samples of the emergency department (ED) population. We analyzed the electronic records of 21,662 consecutive patient visits at an urban, academic ED. From this population, we simulated different models of study recruitment in the ED by using 2 sample sizes (n=200 and n=400) and 4 sampling methods: true random, random 4-hour time blocks by exact sample size, random 4-hour time blocks by a predetermined number of blocks, and convenience or "business hours." For each method and sample size, we obtained 1,000 samples from the population. Using χ(2) tests, we measured the number of statistically significant differences between the sample and the population for 8 variables (age, sex, race/ethnicity, language, triage acuity, arrival mode, disposition, and payer source). Then, for each variable, method, and sample size, we compared the proportion of the 1,000 samples that differed from the overall ED population to the expected proportion (5%). Only the true random samples represented the population with respect to sex, race/ethnicity, triage acuity, mode of arrival, language, and payer source in at least 95% of the samples. Patient samples obtained using random 4-hour time blocks and business hours sampling systematically differed from the overall ED patient population for several important demographic and clinical variables. However, the magnitude of these differences was not large. Common sampling strategies selected for ED-based studies may affect parameter estimates for several representative population variables. However, the potential for bias for these variables appears small. Copyright © 2012. Published by Mosby, Inc.

  15. Designed to deter. Community barriers to physical activity for people with visual or motor impairments.

    PubMed

    Kirchner, Corinne E; Gerber, Elaine G; Smith, Brooke C

    2008-04-01

    People with disabilities are more likely to be obese, in poor health, and get less physical activity than the general population. However, research on community factors for physical activity has generally either excluded most people with disabilities, or overlooked relevant factors of community accessibility. This exploratory study investigated environmental factors affecting people with motor impairments and people with visual impairments in urban neighborhoods. Quantitative and qualitative methods were used with a nonrandom sample (n=134) of users of four types of assistive mobility technologies: guide dogs, long canes, and motorized and manual wheelchairs. From July 2005 to August 2006, the sample participated in two telephone surveys. Between the surveys, a stratified random subsample (n =32) engaged in an ethnographic phase of observation and interviews. Most participants in all groups using assistive mobility technologies rated their neighborhoods as accessible, although they also reported many specific barriers. Users of assistive mobility technologies differed in the amount of reported physical activity and on specific barriers. Problems with sidewalk pavement and puddles/poor drainage were the most frequently mentioned environmental barriers, by 90% and 80%, respectively. Users of assistive mobility technologies were more similar on main strategies for dealing with barriers. All groups reported having to plan routes for outings, to alter planned routes, to go more slowly than planned, or to wait for a different time. Despite legislative requirements for accommodation, people with disabilities face barriers to physical activity, both in the built and social environments. Determined people with disabilities were able to overcome barriers, but required additional expenditure of resources to do so. Community design that can include people with disabilities requires detailed understanding of barriers specific both to types of impairments and to different types of assistive mobility technologies.

  16. Twin Birth Study: 2-year neurodevelopmental follow-up of the randomized trial of planned cesarean or planned vaginal delivery for twin pregnancy.

    PubMed

    Asztalos, Elizabeth V; Hannah, Mary E; Hutton, Eileen K; Willan, Andrew R; Allen, Alexander C; Armson, B Anthony; Gafni, Amiram; Joseph, K S; Ohlsson, Arne; Ross, Susan; Sanchez, J Johanna; Mangoff, Kathryn; Barrett, Jon F R

    2016-03-01

    The Twin Birth Study randomized women with uncomplicated pregnancies, between 32(0/7)-38(6/7) weeks' gestation where the first twin was in cephalic presentation, to a policy of either a planned cesarean or planned vaginal delivery. The primary analysis showed that planned cesarean delivery did not increase or decrease the risk of fetal/neonatal death or serious neonatal morbidity as compared with planned vaginal delivery. This study presents the secondary outcome of death or neurodevelopmental delay at 2 years of age. A total of 4603 children from the initial cohort of 5565 fetuses/infants (83%) contributed to the outcome of death or neurodevelopmental delay. Surviving children were screened using the Ages and Stages Questionnaire with abnormal scores validated by a clinical neurodevelopmental assessment. The effect of planned cesarean vs planned vaginal delivery on death or neurodevelopmental delay was quantified using a logistic model to control for stratification variables and using generalized estimating equations to account for the nonindependence of twin births. Baseline maternal, pregnancy, and infant characteristics were similar. Mean age at assessment was 26 months. There was no significant difference in the outcome of death or neurodevelopmental delay: 5.99% in the planned cesarean vs 5.83% in the planned vaginal delivery group (odds ratio, 1.04; 95% confidence interval, 0.77-1.41; P = .79). A policy of planned cesarean delivery provides no benefit to children at 2 years of age compared with a policy of planned vaginal delivery in uncomplicated twin pregnancies between 32(0/7)-38(6/7)weeks' gestation where the first twin is in cephalic presentation. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Sampling Plans for the Thrips Frankliniella schultzei (Thysanoptera: Thripidae) in Three Lettuce Varieties.

    PubMed

    Silva, Alisson R; Rodrigues-Silva, Nilson; Pereira, Poliana S; Sarmento, Renato A; Costa, Thiago L; Galdino, Tarcísio V S; Picanço, Marcelo C

    2017-12-05

    The common blossom thrips, Frankliniella schultzei Trybom (Thysanoptera: Thripidae), is an important lettuce pest worldwide. Conventional sampling plans are the first step in implementing decision-making systems into integrated pest management programs. However, this tool is not available for F. schultzei infesting lettuce crops. Thus, the objective of this work was to develop a conventional sampling plan for F. schultzei in lettuce crops. Two sampling techniques (direct counting and leaf beating on a white plastic tray) were compared in crisphead, looseleaf, and Boston lettuce varieties before and during head formation. The frequency distributions of F. schultzei densities in lettuce crops were assessed, and the number of samples required to compose the sampling plan was determined. Leaf beating on a white plastic tray was the best sampling technique. F. schultzei densities obtained with this technique were fitted to the negative binomial distribution with a common aggregation parameter (common K = 0.3143). The developed sampling plan is composed of 91 samples per field and presents low errors in its estimates (up to 20%), fast execution time (up to 47 min), and low cost (up to US $1.67 per sampling area). This sampling plan can be used as a tool for integrated pest management in lettuce crops, assisting with reliable decision making in different lettuce varieties before and during head formation. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. The Slope of Change: An Environmental Management Approach to Reduce Drinking on a Day of Celebration at a U.S. College

    PubMed Central

    Marchell, Timothy C.; Lewis, Deborah D.; Croom, Katherine; Lesser, Martin L.; Murphy, Susan H.; Reyna, Valerie F.; Frank, Jeremy; Staiano-Coico, Lisa

    2013-01-01

    OBJECTIVE This research extends the literature on event-specific environmental management with a case study evaluation of an intervention designed to reduce student drinking at a university's year-end celebration. PARTICIPANTS Cornell University undergraduates were surveyed each May from 2001 through 2009. Sample sizes ranged from 322 to 1,973. METHODS Randomly sampled surveys were conducted after a large, annual spring campus celebration. An environmental management plan was initiated in 2003 that included increased enforcement of the minimum age drinking law (MADL). RESULTS In the short-term, drinking at the campus celebration decreased while drinking before the event increased. Over time, the intervention significantly reduced high-risk drinking on the day of the event, especially among those under the age of 21. CONCLUSION These findings are contrary to the argument that enforcement of MADLs simply lead to increased high-risk drinking, and therefore have implications for how colleges approach the challenge of student alcohol misuse. PMID:23930747

  19. Association between mental well-being, depression, and periodontal attachment level among young adults of the postwar Sebha city, Libya: A pilot study.

    PubMed

    Peeran, Syed Wali; Kumar, Naveen P G; Azaruk, Faiza Abdelkader Ahmed; Alsaid, Fatma Mojtaba; Abdalla, Khaled Awidat; Mugrabi, Marei Hamed; Peeran, Syed Ali

    2014-07-01

    The present study was aimed to investigate the association of mental well-being and depression with periodontal clinical attachment loss among young adults in postwar urban population of Sebha city, Libya. Mental well-being and depression were assessed using Arabic versions of World Health Organization (WHO) five well-being index and major depression inventory (ICD-10), respectively. Random sample of 149 subjects were studied. Degree of periodontal attachment was measured at six sites per tooth using a rigid manual periodontal probe. A total of 59.11% of the studied samples had healthy mental well-being state, whereas 40.81% had poor mental well-being. The severity of depression was stronger in males than in females. In the present study mental well-being, depression, and all its categories did not have any significant effect on periodontal attachment loss. Further studies and health interventions can be planned based on this data.

  20. Appendix E - Sample Production Facility Plan

    EPA Pesticide Factsheets

    This sample Spill Prevention, Control and Countermeasure (SPCC) Plan in Appendix E is intended to provide examples and illustrations of how a production facility could address a variety of scenarios in its SPCC Plan.

  1. A Bayesian sequential design with adaptive randomization for 2-sided hypothesis test.

    PubMed

    Yu, Qingzhao; Zhu, Lin; Zhu, Han

    2017-11-01

    Bayesian sequential and adaptive randomization designs are gaining popularity in clinical trials thanks to their potentials to reduce the number of required participants and save resources. We propose a Bayesian sequential design with adaptive randomization rates so as to more efficiently attribute newly recruited patients to different treatment arms. In this paper, we consider 2-arm clinical trials. Patients are allocated to the 2 arms with a randomization rate to achieve minimum variance for the test statistic. Algorithms are presented to calculate the optimal randomization rate, critical values, and power for the proposed design. Sensitivity analysis is implemented to check the influence on design by changing the prior distributions. Simulation studies are applied to compare the proposed method and traditional methods in terms of power and actual sample sizes. Simulations show that, when total sample size is fixed, the proposed design can obtain greater power and/or cost smaller actual sample size than the traditional Bayesian sequential design. Finally, we apply the proposed method to a real data set and compare the results with the Bayesian sequential design without adaptive randomization in terms of sample sizes. The proposed method can further reduce required sample size. Copyright © 2017 John Wiley & Sons, Ltd.

  2. Attitudes toward issues affecting Sarasota Bay

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

    Rayburn, J.D.; Heald, G.R.

    1995-06-20

    The Sarasota Bay National Estuary Program (SBNEP) contracted with the Communication Research Center (CRC) of the Florida State University to conduct a public opinion survey of residents of Sarasota and Manatee, Florida counties to ascertain residents` attitudes toward issues of interest to the SBNEP. The survey was conducted in the final year (1995) of the SBNEP planning phase to determine changes in the public`s perception of bay issues, awareness of restoration efforts, and as a comparison tool to the initial survey conducted in 1990. The survey also provided information necessary for development and implementation of the Comprehensive Conservation and Managementmore » Plan (CCMP). Five hundred, seventy-eight respondents, chosen at random, were interviewed by telephone during February 1995. The survey had a maximum estimated sampling error of approximately plus or minus four percent (4%) at the 95% level of confidence. Survey results include: just 41% of the respondents were aware of some type of clean up activities going on in the community. This information points to the need for continued assertive public education and outreach efforts to support Sarasota Bay restoration.« less

  3. Transportation Demand Management Planning At Multi-Tenant Buildings, An Example Of Tdm Planning During Project

    DOT National Transportation Integrated Search

    1988-09-01

    THIS GUIDE FOR DEVELOPERS, BUILDING OWNERS AND BUILDING MANAGERS IS ONE IN A SERIES OF SAMPLES OF TDM PLANS THAT ILLUSTRATE THE DESIGN AND PROPOSED APPLICATION OF TDM STRATEGIES. THIS SAMPLE PLAN WAS PREPARED FOR A FICTITIOUS BUILDING MANAGER NEAR DO...

  4. Assessing the feasibility of the Effectiveness of Discontinuing Bisphosphonates trial: a pilot study.

    PubMed

    Wright, N C; Foster, P J; Mudano, A S; Melnick, J A; Lewiecki, M E; Shergy, W J; Curtis, J R; Cutter, G R; Danila, M I; Kilgore, M L; Lewis, E C; Morgan, S L; Redden, D T; Warriner, A H; Saag, K G

    2017-08-01

    The Effectiveness of Discontinuing Bisphosphonates (EDGE) study is a planned pragmatic clinical trial to guide "drug holiday" clinical decision making. This pilot study assessed work flow and feasibility of such a study. While participant recruitment and treatment adherence were suboptimal, administrative procedures were generally feasible and minimally disrupted clinic flow. The comparative effectiveness of continuing or discontinuing long-term alendronate (ALN) on fractures is unknown. A large pragmatic ALN discontinuation study has potential to answer this question. We conducted a 6-month pilot study of the planned the EDGE study among current long-term ALN users (women aged ≥65 with ≥3 years of ALN use) to determine study work flow and feasibility including evaluating the administrative aspects of trial conduct (e.g., time to contract, institutional review board (IRB) approval), assessing rates of site and participant recruitment, and evaluating post-randomization outcomes, including adherence, bisphosphonate-associated adverse events, and participant and site satisfaction. We assessed outcomes 1 and 6 months after randomization. Nine sites participated, including seven community-based medical practices and two academic medical centers. On average (SD), contract execution took 3.4 (2.3) months and IRB approval took 13.9 (4.1) days. Sites recruited 27 participants (13 to continue ALN and 14 to discontinue ALN). Over follow-up, 22% of participants did not adhere to their randomization assignment: 30.8% in the continuation arm and 14.3% in the discontinuation arm. No fractures or adverse events were reported. Sites reported no issues regarding work flow, and participants were highly satisfied with the study. Administrative procedures of the EDGE study were generally feasible, with minimal disruption to clinic flow. In this convenience sample, participant recruitment was suboptimal across most practice sites. Accounting for low treatment arm adherence, a comprehensive recruitment approach will be needed to effectively achieve the scientific goals of the EDGE study.

  5. Introducing reproductive life plan-based information in contraceptive counselling: an RCT.

    PubMed

    Stern, J; Larsson, M; Kristiansson, P; Tydén, T

    2013-09-01

    Can reproductive life plan (RLP)-based information in contraceptive counselling before pregnancy increase women's knowledge of reproduction, and of the importance of folic acid intake in particular? The RLP-based information increased women's knowledge of reproduction including knowledge of folic acid intake. Many women have insufficient knowledge of reproduction, including a health-promoting lifestyle prior to conception, and highly educated women in particular postpone childbearing until an age when their fertile capacity has started to decrease. The study was an randomized controlled trial with one intervention group (IG) and two control groups (CG1, CG2). A sample size calculation indicated that 82 women per group would be adequate. Recruitment took place during 3 months in 2012 and 299 women were included. The women were randomized in blocks of three. All groups received standard care (contraceptive counselling, Chlamydia testing, cervical screening). In addition, women in the IG were given oral and written RLP-based information about reproduction. A total of 299 out of 338 (88%) Swedish-speaking women visiting a Student Health Centre were included (mean age 23 years); response rate was 88%. Before the counselling, women in the IG and the CG1 completed a baseline questionnaire, including questions about lifestyle changes in connection to pregnancy planning, family planning intentions and knowledge of reproduction (e.g. the fecundity of an ovum). At follow-up 2 months after inclusion, a structured telephone interview was performed in all groups (n = 262, 88% participation rate). There was no difference between the groups regarding the mean knowledge score at baseline. The IG scored higher at follow-up than at baseline (P < 0.001); the mean increased from 6.4 to 9.0 out of a maximum 20 points. The women in the CG1 scored no differently at follow-up than at baseline. The difference in the knowledge score between the IG and the two CGs was significant (P < 0.001), whereas no difference was shown between the two CGs. There was no difference between the groups at baseline regarding how many women could mention folic acid intake among the things to do when planning to get pregnant. At follow-up, 22% in the IG, 3% in CG1 and 1% in CG2 mentioned folic acid intake (P < 0.001). At follow-up, more women in the IG also wished to have their last child earlier in life (P < 0.001) than at baseline, while there was no difference in the CG1. As the study sample consisted of university students, it is possible that the effect of the intervention was connected to a high level of education and conclusions for all women of reproductive age should be drawn with caution. The provision of RLP-based information seems to be a feasible tool for promoting reproductive health. Study funding was received from the Faculty of Medicine, Uppsala University, Sweden. There are no conflicts of interest. ClinicalTrial.gov Identifier NCT01739101.

  6. Breaking through the bandwidth barrier in distributed fiber vibration sensing by sub-Nyquist randomized sampling

    NASA Astrophysics Data System (ADS)

    Zhang, Jingdong; Zhu, Tao; Zheng, Hua; Kuang, Yang; Liu, Min; Huang, Wei

    2017-04-01

    The round trip time of the light pulse limits the maximum detectable frequency response range of vibration in phase-sensitive optical time domain reflectometry (φ-OTDR). We propose a method to break the frequency response range restriction of φ-OTDR system by modulating the light pulse interval randomly which enables a random sampling for every vibration point in a long sensing fiber. This sub-Nyquist randomized sampling method is suits for detecting sparse-wideband- frequency vibration signals. Up to MHz resonance vibration signal with over dozens of frequency components and 1.153MHz single frequency vibration signal are clearly identified for a sensing range of 9.6km with 10kHz maximum sampling rate.

  7. 78 FR 57033 - United States Standards for Condition of Food Containers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-17

    ... containers during production. Stationary lot sampling is the process of randomly selecting sample units from.... * * * * * Stationary lot sampling. The process of randomly selecting sample units from a lot whose production has been... less than \\1/16\\-inch Stringy seal (excessive plastic threads showing at edge of seal 222 area...

  8. Middle Level Practices in European International and Department of Defense Schools.

    ERIC Educational Resources Information Center

    Waggoner, V. Christine; McEwin, C. Kenneth

    1993-01-01

    Discusses results of a 1989-90 survey of 70 randomly selected international schools and 70 randomly selected Department of Defense Schools in Europe. Programs and practices surveyed included enrollments, grade organization, curriculum and instructional plans, core subjects, grouping patterns, exploratory courses, advisory programs, and scheduling.…

  9. Health indicators: eliminating bias from convenience sampling estimators.

    PubMed

    Hedt, Bethany L; Pagano, Marcello

    2011-02-28

    Public health practitioners are often called upon to make inference about a health indicator for a population at large when the sole available information are data gathered from a convenience sample, such as data gathered on visitors to a clinic. These data may be of the highest quality and quite extensive, but the biases inherent in a convenience sample preclude the legitimate use of powerful inferential tools that are usually associated with a random sample. In general, we know nothing about those who do not visit the clinic beyond the fact that they do not visit the clinic. An alternative is to take a random sample of the population. However, we show that this solution would be wasteful if it excluded the use of available information. Hence, we present a simple annealing methodology that combines a relatively small, and presumably far less expensive, random sample with the convenience sample. This allows us to not only take advantage of powerful inferential tools, but also provides more accurate information than that available from just using data from the random sample alone. Copyright © 2011 John Wiley & Sons, Ltd.

  10. Development of sampling plans for cotton bolls injured by stink bugs (Hemiptera: Pentatomidae).

    PubMed

    Reay-Jones, F P F; Toews, M D; Greene, J K; Reeves, R B

    2010-04-01

    Cotton, Gossypium hirsutum L., bolls were sampled in commercial fields for stink bug (Hemiptera: Pentatomidae) injury during 2007 and 2008 in South Carolina and Georgia. Across both years of this study, boll-injury percentages averaged 14.8 +/- 0.3 (SEM). At average boll injury treatment levels of 10, 20, 30, and 50%, the percentage of samples with at least one injured boll was 82, 97, 100, and 100%, respectively. Percentage of field-sampling date combinations with average injury < 10, 20, 30, and 50% was 35, 80, 95, and 99%, respectively. At the average of 14.8% boll injury or 2.9 injured bolls per 20-boll sample, 112 samples at Dx = 0.1 (within 10% of the mean) were required for population estimation, compared with only 15 samples at Dx = 0.3. Using a sample size of 20 bolls, our study indicated that, at the 10% threshold and alpha = beta = 0.2 (with 80% confidence), control was not needed when <1.03 bolls were injured. The sampling plan required continued sampling for a range of 1.03-3.8 injured bolls per 20-boll sample. Only when injury was > 3.8 injured bolls per 20-boll sample was a control measure needed. Sequential sampling plans were also determined for thresholds of 20, 30, and 50% injured bolls. Sample sizes for sequential sampling plans were significantly reduced when compared with a fixed sampling plan (n=10) for all thresholds and error rates.

  11. Pseudo CT estimation from MRI using patch-based random forest

    NASA Astrophysics Data System (ADS)

    Yang, Xiaofeng; Lei, Yang; Shu, Hui-Kuo; Rossi, Peter; Mao, Hui; Shim, Hyunsuk; Curran, Walter J.; Liu, Tian

    2017-02-01

    Recently, MR simulators gain popularity because of unnecessary radiation exposure of CT simulators being used in radiation therapy planning. We propose a method for pseudo CT estimation from MR images based on a patch-based random forest. Patient-specific anatomical features are extracted from the aligned training images and adopted as signatures for each voxel. The most robust and informative features are identified using feature selection to train the random forest. The well-trained random forest is used to predict the pseudo CT of a new patient. This prediction technique was tested with human brain images and the prediction accuracy was assessed using the original CT images. Peak signal-to-noise ratio (PSNR) and feature similarity (FSIM) indexes were used to quantify the differences between the pseudo and original CT images. The experimental results showed the proposed method could accurately generate pseudo CT images from MR images. In summary, we have developed a new pseudo CT prediction method based on patch-based random forest, demonstrated its clinical feasibility, and validated its prediction accuracy. This pseudo CT prediction technique could be a useful tool for MRI-based radiation treatment planning and attenuation correction in a PET/MRI scanner.

  12. Appendix F - Sample Contingency Plan

    EPA Pesticide Factsheets

    This sample Contingency Plan in Appendix F is intended to provide examples of contingency planning as a reference when a facility determines that the required secondary containment is impracticable, pursuant to 40 CFR §112.7(d).

  13. Appendix D - Sample Bulk Storage Facility Plan

    EPA Pesticide Factsheets

    This sample Spill Prevention, Control and Countermeasure (SPCC) Plan in Appendix D is intended to provide examples and illustrations of how a bulk storage facility could address a variety of scenarios in its SPCC Plan.

  14. Birth-Preparedness for Maternal Health: Findings from Koupéla District, Burkina Faso

    PubMed Central

    Sangli, Gabriel; Dineen, Rebecca; Rawlins, Barbara; Yaméogo, Mathias; Baya, Banza

    2006-01-01

    Maternal mortality is a global burden, with more than 500,000 women dying each year due to pregnancy and childbirth-related complications. Birth-preparedness and complication readiness is a comprehensive strategy to improve the use of skilled providers at birth, the key intervention to decrease maternal mortality. Birth-preparedness and complication readiness include many elements, including: (a) knowledge of danger signs; (b) plan for where to give birth; (c) plan for a birth attendant; (d) plan for transportation; and (e) plan for saving money. The 2003 Burkina Faso Demographic and Health Survey indicated that only 38.5% of women gave birth with the assistance of a skilled provider. The Maternal and Neonatal Health Program of JHPIEGO implemented a district-based model service-delivery system in Koupéla, Burkina Faso, during 2001–2004, to increase the use of skilled providers during pregnancy and childbirth. In 2004, a cross-sectional survey with a random sample of respondents was conducted to measure the impact of birth-preparedness and complication readiness on the use of skilled providers at birth. Of the 180 women who had given birth within 12 months of the survey, 46.1% had a plan for transportation, and 83.3% had a plan to save money. Women with these plans were more likely to give birth with the assistance of a skilled provider (p=0.07 and p=0.03 respectively). Controlling for education, parity, average distance to health facility, and the number of antenatal care visits, planning to save money was associated with giving birth with the assistance of a skilled provider (p=0.05). Qualitative interviews with women who had given birth within 12 months of the survey (n=30) support these findings. Most women saved money for delivery, but had less concrete plans for transportation. These findings highlight how birth-preparedness and complication readiness may be useful in increasing the use of skilled providers at birth, especially for women with a plan for saving money during pregnancy. PMID:17591346

  15. Advance care planning for older people in Australia presenting to the emergency department from the community or residential aged care facilities.

    PubMed

    Street, Maryann; Ottmann, Goetz; Johnstone, Megan-Jane; Considine, Julie; Livingston, Patricia M

    2015-09-01

    The purpose of this retrospective, cross-sectional study was to determine the prevalence of advance care planning (ACP) among older people presenting to an Emergency Department (ED) from the community or a residential aged care facility. The study sample comprised 300 older people (aged 65+ years) presenting to three Victorian EDs in 2011. A total of 150 patients transferred from residential aged care to ED were randomly selected and then matched to 150 people who lived in the community and attended the ED by age, gender, reason for ED attendance and triage category on arrival. Overall prevalence of ACP was 13.3% (n = 40/300); over one-quarter (26.6%, n = 40/150) of those presenting to the ED from residential aged care had a documented Advance Care Plan, compared to none (0%, n = 0/150) of the people from the community. There were no significant differences in the median ED length of stay, number of investigations and interventions undertaken in ED, time seen by a doctor or rate of hospital admission for those with an Advance Care Plan compared to those without. Those with a comorbidity of cerebrovascular disease or dementia and those assessed with impaired brain function were more likely to have a documented Advance Care Plan on arrival at ED. Length of hospital stay was shorter for those with an Advance Care Plan [median (IQR) = 3 days (2-6) vs. 6 days (2-10), P = 0.027] and readmission lower (0% vs. 13.7%). In conclusion, older people from the community transferred to ED were unlikely to have a documented Advance Care Plan. Those from residential aged care who were cognitively impaired more frequently had an Advance Care Plan. In the ED, decisions of care did not appear to be influenced by the presence or absence of Advance Care Plans, but length of hospital admission was shorter for those with an Advance Care Plan. © 2014 John Wiley & Sons Ltd.

  16. 34 CFR Appendix A to Subpart N of... - Sample Default Prevention Plan

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 3 2011-07-01 2011-07-01 false Sample Default Prevention Plan A Appendix A to Subpart N of Part 668 Education Regulations of the Offices of the Department of Education (Continued) OFFICE... Default Rates Appendix A to Subpart N of Part 668—Sample Default Prevention Plan This appendix is provided...

  17. 40 CFR Appendix Xi to Part 86 - Sampling Plans for Selective Enforcement Auditing of Light-Duty Vehicles

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Sampling Plans for Selective Enforcement Auditing of Light-Duty Vehicles XI Appendix XI to Part 86 Protection of Environment ENVIRONMENTAL... Enforcement Auditing of Light-Duty Vehicles 40% AQL Table 1—Sampling Plan Code Letter Annual sales of...

  18. Formative evaluation of a participatory women's group intervention to improve reproductive and women's health outcomes in rural Bangladesh: a controlled before and after study

    PubMed Central

    Harris-Fry, Helen A; Azad, Kishwar; Younes, Leila; Kuddus, Abdul; Shaha, Sanjit; Nahar, Tasmin; Hossen, Munir; Costello, Anthony; Fottrell, Edward

    2016-01-01

    Background Women's groups using participatory methods reduced newborn mortality in rural areas of low income countries. Our study assessed a participatory women's group intervention that focused on women's health, nutrition and family planning. Methods The study was conducted in three districts in Bangladesh between October 2011 and March 2013, covering a population of around 230 000. On the basis of allocation for the preceding cluster randomised trials, three unions per district were randomly allocated to receive a women's group intervention and three per district were control clusters. Outcomes included unmet need for family planning, morbidity, dietary diversity, night blindness, healthcare decision-making and knowledge of sexual and reproductive health, nutrition and anaemia. A difference-in-difference analysis was used to adjust for secular trends and baseline differences between women taking part in the intervention and a random sample from control clusters. Results We interviewed 5355 (91% response rate) women before the intervention and 5128 after (96% response rate). There were significant improvements in women's dietary diversity score (increase of 0.2 (95% CI 0.1 to 0.3)) and participation in healthcare decision-making (proportion increase (95% CI) 14.0% (10.6% to 17.4%)). There were also increases in knowledge about: contraception (4.2% (2.0% to 6.3%)), ways to treat (55.4% (52.2% to 58.5%)) and prevent (71.0% (68.0% to 74.1%)) sexually transmitted infections, nutrition (46.6% (43.6% to 49.6%)) and anaemia prevention (62.8% (60.9% to 64.6%)). There were no significant differences in unmet need for family planning, morbidity or night blindness. Conclusions Participatory women's groups have considerable potential to improve women's health knowledge, but evidence of impact on certain outcomes is lacking. Further formative work and intervention development is needed to optimise the impact of this approach for women's health. PMID:26739272

  19. Microbiological sampling plan based on risk classification to verify supplier selection and production of served meals in food service operation.

    PubMed

    Lahou, Evy; Jacxsens, Liesbeth; Van Landeghem, Filip; Uyttendaele, Mieke

    2014-08-01

    Food service operations are confronted with a diverse range of raw materials and served meals. The implementation of a microbial sampling plan in the framework of verification of suppliers and their own production process (functionality of their prerequisite and HACCP program), demands selection of food products and sampling frequencies. However, these are often selected without a well described scientifically underpinned sampling plan. Therefore, an approach on how to set-up a focused sampling plan, enabled by a microbial risk categorization of food products, for both incoming raw materials and meals served to the consumers is presented. The sampling plan was implemented as a case study during a one-year period in an institutional food service operation to test the feasibility of the chosen approach. This resulted in 123 samples of raw materials and 87 samples of meal servings (focused on high risk categorized food products) which were analyzed for spoilage bacteria, hygiene indicators and food borne pathogens. Although sampling plans are intrinsically limited in assessing the quality and safety of sampled foods, it was shown to be useful to reveal major non-compliances and opportunities to improve the food safety management system in place. Points of attention deduced in the case study were control of Listeria monocytogenes in raw meat spread and raw fish as well as overall microbial quality of served sandwiches and salads. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Data Validation Package August 2015 Groundwater Sampling at the Grand Junction, Colorado, Disposal Site October 2015

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

    Frazier, William; Baur, Gary

    2015-11-03

    The 1998 Interim Long-Term Surveillance Plan for the Cheney Disposal Site Near Grand Junction, Colorado, requires annual monitoring to assess the performance of the disposal cell. Monitoring wells 0731, 0732 and 0733 were sampled as specified in the plan. Sampling and analyses were conducted in accordance with Sampling and Analysis Plan for the U.S. Department of Energy Office of Legacy Management Sites.

  1. A Systematic Review of Surgical Randomized Controlled Trials: Part 2. Funding Source, Conflict of Interest, and Sample Size in Plastic Surgery.

    PubMed

    Voineskos, Sophocles H; Coroneos, Christopher J; Ziolkowski, Natalia I; Kaur, Manraj N; Banfield, Laura; Meade, Maureen O; Chung, Kevin C; Thoma, Achilleas; Bhandari, Mohit

    2016-02-01

    The authors examined industry support, conflict of interest, and sample size in plastic surgery randomized controlled trials that compared surgical interventions. They hypothesized that industry-funded trials demonstrate statistically significant outcomes more often, and randomized controlled trials with small sample sizes report statistically significant results more frequently. An electronic search identified randomized controlled trials published between 2000 and 2013. Independent reviewers assessed manuscripts and performed data extraction. Funding source, conflict of interest, primary outcome direction, and sample size were examined. Chi-squared and independent-samples t tests were used in the analysis. The search identified 173 randomized controlled trials, of which 100 (58 percent) did not acknowledge funding status. A relationship between funding source and trial outcome direction was not observed. Both funding status and conflict of interest reporting improved over time. Only 24 percent (six of 25) of industry-funded randomized controlled trials reported authors to have independent control of data and manuscript contents. The mean number of patients randomized was 73 per trial (median, 43, minimum, 3, maximum, 936). Small trials were not found to be positive more often than large trials (p = 0.87). Randomized controlled trials with small sample size were common; however, this provides great opportunity for the field to engage in further collaboration and produce larger, more definitive trials. Reporting of trial funding and conflict of interest is historically poor, but it greatly improved over the study period. Underreporting at author and journal levels remains a limitation when assessing the relationship between funding source and trial outcomes. Improved reporting and manuscript control should be goals that both authors and journals can actively achieve.

  2. Northwest Forest Plan—the first 10 years (1994–2003): preliminary assessment of the condition of watersheds.

    Treesearch

    Kirsten Gallo; Steven H. Lanigan; Peter Eldred; Sean N. Gordon; Chris Moyer

    2005-01-01

    We aggregated road, vegetation, and inchannel data to assess the condition of sixth-field watersheds and describe the distribution of the condition of watersheds in the Northwest Forest Plan (the Plan) area. The assessment is based on 250 watersheds selected at random within the Plan area. The distributions of conditions are presented for watersheds and for many of the...

  3. Random phase detection in multidimensional NMR.

    PubMed

    Maciejewski, Mark W; Fenwick, Matthew; Schuyler, Adam D; Stern, Alan S; Gorbatyuk, Vitaliy; Hoch, Jeffrey C

    2011-10-04

    Despite advances in resolution accompanying the development of high-field superconducting magnets, biomolecular applications of NMR require multiple dimensions in order to resolve individual resonances, and the achievable resolution is typically limited by practical constraints on measuring time. In addition to the need for measuring long evolution times to obtain high resolution, the need to distinguish the sign of the frequency constrains the ability to shorten measuring times. Sign discrimination is typically accomplished by sampling the signal with two different receiver phases or by selecting a reference frequency outside the range of frequencies spanned by the signal and then sampling at a higher rate. In the parametrically sampled (indirect) time dimensions of multidimensional NMR experiments, either method imposes an additional factor of 2 sampling burden for each dimension. We demonstrate that by using a single detector phase at each time sample point, but randomly altering the phase for different points, the sign ambiguity that attends fixed single-phase detection is resolved. Random phase detection enables a reduction in experiment time by a factor of 2 for each indirect dimension, amounting to a factor of 8 for a four-dimensional experiment, albeit at the cost of introducing sampling artifacts. Alternatively, for fixed measuring time, random phase detection can be used to double resolution in each indirect dimension. Random phase detection is complementary to nonuniform sampling methods, and their combination offers the potential for additional benefits. In addition to applications in biomolecular NMR, random phase detection could be useful in magnetic resonance imaging and other signal processing contexts.

  4. High-speed imaging using CMOS image sensor with quasi pixel-wise exposure

    NASA Astrophysics Data System (ADS)

    Sonoda, T.; Nagahara, H.; Endo, K.; Sugiyama, Y.; Taniguchi, R.

    2017-02-01

    Several recent studies in compressive video sensing have realized scene capture beyond the fundamental trade-off limit between spatial resolution and temporal resolution using random space-time sampling. However, most of these studies showed results for higher frame rate video that were produced by simulation experiments or using an optically simulated random sampling camera, because there are currently no commercially available image sensors with random exposure or sampling capabilities. We fabricated a prototype complementary metal oxide semiconductor (CMOS) image sensor with quasi pixel-wise exposure timing that can realize nonuniform space-time sampling. The prototype sensor can reset exposures independently by columns and fix these amount of exposure by rows for each 8x8 pixel block. This CMOS sensor is not fully controllable via the pixels, and has line-dependent controls, but it offers flexibility when compared with regular CMOS or charge-coupled device sensors with global or rolling shutters. We propose a method to realize pseudo-random sampling for high-speed video acquisition that uses the flexibility of the CMOS sensor. We reconstruct the high-speed video sequence from the images produced by pseudo-random sampling using an over-complete dictionary.

  5. ADAPTIVE MATCHING IN RANDOMIZED TRIALS AND OBSERVATIONAL STUDIES

    PubMed Central

    van der Laan, Mark J.; Balzer, Laura B.; Petersen, Maya L.

    2014-01-01

    SUMMARY In many randomized and observational studies the allocation of treatment among a sample of n independent and identically distributed units is a function of the covariates of all sampled units. As a result, the treatment labels among the units are possibly dependent, complicating estimation and posing challenges for statistical inference. For example, cluster randomized trials frequently sample communities from some target population, construct matched pairs of communities from those included in the sample based on some metric of similarity in baseline community characteristics, and then randomly allocate a treatment and a control intervention within each matched pair. In this case, the observed data can neither be represented as the realization of n independent random variables, nor, contrary to current practice, as the realization of n/2 independent random variables (treating the matched pair as the independent sampling unit). In this paper we study estimation of the average causal effect of a treatment under experimental designs in which treatment allocation potentially depends on the pre-intervention covariates of all units included in the sample. We define efficient targeted minimum loss based estimators for this general design, present a theorem that establishes the desired asymptotic normality of these estimators and allows for asymptotically valid statistical inference, and discuss implementation of these estimators. We further investigate the relative asymptotic efficiency of this design compared with a design in which unit-specific treatment assignment depends only on the units’ covariates. Our findings have practical implications for the optimal design and analysis of pair matched cluster randomized trials, as well as for observational studies in which treatment decisions may depend on characteristics of the entire sample. PMID:25097298

  6. Underground Test Area Calendar Year 2014 Annual Sampling Analysis Report Nevada National Security Site, Nevada, Revision 0

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

    Farnham, Irene

    2016-12-01

    This report presents the analytical data for the 2014 fiscal year (FY) and calendar year (CY) (October 1, 2013, through December 31, 2014), and an evaluation of the data to ensure that the Sampling Plan’s objectives are met. In addition to samples collected and analyzed for the Sampling Plan, some NNSS wells are monitored by NNSA/NFO to demonstrate compliance with State-issued water discharge permits; with protection of groundwater from ongoing radiological waste disposal activities (compliance wells); and to demonstrate that the onsite drinking water supply is below SDWA maximum contaminant levels (MCLs) (public water system [PWS] wells). While not allmore » sampled locations are required by the Sampling Plan, these samples are relevant to its objectives and are therefore presented herein for completeness purposes. Special investigations that took place in 2014 that are relevant to the Sampling Plan are also presented. This is the first annual report released to support Sampling Plan implementation.« less

  7. SAMPLING OF CONTAMINATED SITES

    EPA Science Inventory

    A critical aspect of characterization of the amount and species of contamination of a hazardous waste site is the sampling plan developed for that site. f the sampling plan is not thoroughly conceptualized before sampling takes place, then certain critical aspects of the limits o...

  8. Changing Our Conversations

    ERIC Educational Resources Information Center

    Porto, Mark

    2007-01-01

    In this article, a principal is inspired to change the conversations with students and staff members from discipline and deficit to hope and planning for future achievement. He wants conversations to be more about academic goals and decision making and less about discipline and random acceptance of postsecondary plans. He has asked all staff…

  9. A Simulation Game for the Study of State Policies.

    ERIC Educational Resources Information Center

    Enzer, Selwyn; And Others

    A simulated planning conference used both informed experts (simulating state planners and societal groups) and "Monte Carlo" procedures (simulating random events) to identify some possible futures for the state of Connecticut and to examine rational planning behavior patterns. In the simulation the participants were divided into two…

  10. 49 CFR 244.13 - Subjects to be addressed in a Safety Integration Plan involving an amalgamation of operations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... shall identify classroom and field courses, lectures, tests, and other educational or instructional... shall identify the post-accident toxicological testing, reasonable cause testing, and random alcohol and... and maintenance, and any planned amendments or modifications to capital improvement and research and...

  11. 49 CFR 244.13 - Subjects to be addressed in a Safety Integration Plan involving an amalgamation of operations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... shall identify classroom and field courses, lectures, tests, and other educational or instructional... shall identify the post-accident toxicological testing, reasonable cause testing, and random alcohol and... and maintenance, and any planned amendments or modifications to capital improvement and research and...

  12. 49 CFR 244.13 - Subjects to be addressed in a Safety Integration Plan involving an amalgamation of operations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... shall identify classroom and field courses, lectures, tests, and other educational or instructional... shall identify the post-accident toxicological testing, reasonable cause testing, and random alcohol and... and maintenance, and any planned amendments or modifications to capital improvement and research and...

  13. 49 CFR 244.13 - Subjects to be addressed in a Safety Integration Plan involving an amalgamation of operations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... shall identify classroom and field courses, lectures, tests, and other educational or instructional... shall identify the post-accident toxicological testing, reasonable cause testing, and random alcohol and... and maintenance, and any planned amendments or modifications to capital improvement and research and...

  14. Enhancing English Language Planning Strategy Using a WebQuest Model

    ERIC Educational Resources Information Center

    Al-Sayed, Rania Kamal Muhammad; Abdel-Haq, Eman Muhammad; El-Deeb, Mervat Abou-Bakr; Ali, Mahsoub Abdel-Sadeq

    2016-01-01

    The present study aimed at developing English language planning strategy of second year distinguished governmental language preparatory school pupils using the a WebQuest model. Fifty participants from second year at Hassan Abu-Bakr Distinguished Governmental Language School at Al-Qanater Al-Khairia (Qalubia Governorate) were randomly assigned…

  15. Impact of advance care planning on the care of patients with heart failure: study protocol for a randomized controlled trial.

    PubMed

    Malhotra, Chetna; Sim, David Kheng Leng; Jaufeerally, Fazlur; Vikas, Nivedita Nadkarni; Sim, Genevieve Wong Cheng; Tan, Boon Cheng; Ng, Clarice Shu Hwa; Tho, Pei Leng; Lim, Jingfen; Chuang, Claire Ya-Ting; Fong, Florence Hui Mei; Liu, Joy; Finkelstein, Eric A

    2016-06-10

    Despite the promise and popularity of advance care planning, there is insufficient evidence that advance care planning helps patients to meet their end-of-life care preferences, especially in Asian settings. Thus, the proposed study aims to assess whether patients with advanced heart failure who are receiving advance care planning have a greater likelihood of receiving end-of-life care consistent with their preferences compared to patients receiving usual care. Secondary objectives are to compare differences in health care expenditures, quality of life, anxiety and depression, understanding of own illness, participation in decision-making and concordance with their caregiver's preferences for end-of-life care, between patients with advanced heart failure receiving advance care planning and usual care. This is a two-arm randomized controlled trial of advance care planning versus usual care (control) conducted at two institutions in Singapore. Two hundred and eighty-two patients with advanced heart failure (n = 94 in the advance care planning arm; n = 188 in the control arm receiving usual care) will be recruited from these centers and followed for 1 year or until they die, whichever is earlier. Additionally, the study will include up to one caregiver per patient enrolled. If advance care planning is proven to be effective, the results will help to promote its uptake among health care providers and patients both within Singapore and in other countries. NCT02299180 . Registered on 18 November 2014.

  16. Adaptive Peer Sampling with Newscast

    NASA Astrophysics Data System (ADS)

    Tölgyesi, Norbert; Jelasity, Márk

    The peer sampling service is a middleware service that provides random samples from a large decentralized network to support gossip-based applications such as multicast, data aggregation and overlay topology management. Lightweight gossip-based implementations of the peer sampling service have been shown to provide good quality random sampling while also being extremely robust to many failure scenarios, including node churn and catastrophic failure. We identify two problems with these approaches. The first problem is related to message drop failures: if a node experiences a higher-than-average message drop rate then the probability of sampling this node in the network will decrease. The second problem is that the application layer at different nodes might request random samples at very different rates which can result in very poor random sampling especially at nodes with high request rates. We propose solutions for both problems. We focus on Newscast, a robust implementation of the peer sampling service. Our solution is based on simple extensions of the protocol and an adaptive self-control mechanism for its parameters, namely—without involving failure detectors—nodes passively monitor local protocol events using them as feedback for a local control loop for self-tuning the protocol parameters. The proposed solution is evaluated by simulation experiments.

  17. Use of crisis management interventions among suicidal patients: Results of a randomized controlled trial.

    PubMed

    Bryan, Craig J; May, Alexis M; Rozek, David C; Williams, Sean R; Clemans, Tracy A; Mintz, Jim; Leeson, Bruce; Burch, T Scott

    2018-05-10

    Previous research supports the efficacy of the crisis response plan (CRP) for the reduction of suicidal behaviors as compared to treatment as usual (TAU). Patient perspectives and use of the CRP, and their relationship to later suicidal thoughts, remain unknown. A secondary analysis of a randomized clinical trial comparing a standard CRP (S-CRP), a CRP enhanced with reasons for living (E-CRP), and TAU in a sample of 97 active-duty U.S. Army personnel was conducted. Participants were asked about their use, perceptions, and recall of each intervention. Generalized estimating equations were used to test the conditional effects of intervention use, perceptions, and recall on severity of suicide ideation during follow-up. Across all treatment groups, over 80% of participants retained their written CRP up to 6 months later, but less than 25% had the written plan in their physical possession at the time of each assessment. Participants in S-CRP and E-CRP were more likely to recall self-management strategies and sources of social support. Participants in TAU were more likely to recall use of professional healthcare services and crisis management services. All three interventions were rated as highly useful. More frequent use of the E-CRP and recall of its components were associated with significantly reduced suicide ideation as compared to TAU. Both CRPs have high acceptability ratings. The effect of both CRPs on reduced suicide ideation is associated with patient recall of components. More frequent use of the E-CRP is associated with larger reductions in suicide ideation. © 2018 Wiley Periodicals, Inc.

  18. Generating Random Samples of a Given Size Using Social Security Numbers.

    ERIC Educational Resources Information Center

    Erickson, Richard C.; Brauchle, Paul E.

    1984-01-01

    The purposes of this article are (1) to present a method by which social security numbers may be used to draw cluster samples of a predetermined size and (2) to describe procedures used to validate this method of drawing random samples. (JOW)

  19. Microcredit, family planning programs, and contraceptive behavior: evidence from a field experiment in Ethiopia.

    PubMed

    Desai, Jaikishan; Tarozzi, Alessandro

    2011-05-01

    The impact of community-based family planning programs and access to credit on contraceptive use, fertility, and family size preferences has not been established conclusively in the literature. We provide additional evidence on the possible effect of such programs by describing the results of a randomized field experiment whose main purpose was to increase the use of contraceptive methods in rural areas of Ethiopia. In the experiment, administrative areas were randomly allocated to one of three intervention groups or to a fourth control group. In the first intervention group, both credit and family planning services were provided and the credit officers also provided information on family planning. Only credit or family planning services, but not both, were provided in the other two intervention groups, while areas in the control group received neither type of service. Using pre- and post-intervention surveys, we find that neither type of program, combined or in isolation, led to an increase in contraceptive use that is significantly greater than that observed in the control group. We conjecture that the lack of impact has much to do with the mismatch between women's preferred contraceptive method (injectibles) and the contraceptives provided by community-based agents (pills and condoms).

  20. Development and Validation of a Predictive Model to Identify Individuals Likely to Have Undiagnosed Chronic Obstructive Pulmonary Disease Using an Administrative Claims Database.

    PubMed

    Moretz, Chad; Zhou, Yunping; Dhamane, Amol D; Burslem, Kate; Saverno, Kim; Jain, Gagan; Devercelli, Giovanna; Kaila, Shuchita; Ellis, Jeffrey J; Hernandez, Gemzel; Renda, Andrew

    2015-12-01

    Despite the importance of early detection, delayed diagnosis of chronic obstructive pulmonary disease (COPD) is relatively common. Approximately 12 million people in the United States have undiagnosed COPD. Diagnosis of COPD is essential for the timely implementation of interventions, such as smoking cessation programs, drug therapies, and pulmonary rehabilitation, which are aimed at improving outcomes and slowing disease progression. To develop and validate a predictive model to identify patients likely to have undiagnosed COPD using administrative claims data. A predictive model was developed and validated utilizing a retro-spective cohort of patients with and without a COPD diagnosis (cases and controls), aged 40-89, with a minimum of 24 months of continuous health plan enrollment (Medicare Advantage Prescription Drug [MAPD] and commercial plans), and identified between January 1, 2009, and December 31, 2012, using Humana's claims database. Stratified random sampling based on plan type (commercial or MAPD) and index year was performed to ensure that cases and controls had a similar distribution of these variables. Cases and controls were compared to identify demographic, clinical, and health care resource utilization (HCRU) characteristics associated with a COPD diagnosis. Stepwise logistic regression (SLR), neural networking, and decision trees were used to develop a series of models. The models were trained, validated, and tested on randomly partitioned subsets of the sample (Training, Validation, and Test data subsets). Measures used to evaluate and compare the models included area under the curve (AUC); index of the receiver operating characteristics (ROC) curve; sensitivity, specificity, positive predictive value (PPV); and negative predictive value (NPV). The optimal model was selected based on AUC index on the Test data subset. A total of 50,880 cases and 50,880 controls were included, with MAPD patients comprising 92% of the study population. Compared with controls, cases had a statistically significantly higher comorbidity burden and HCRU (including hospitalizations, emergency room visits, and medical procedures). The optimal predictive model was generated using SLR, which included 34 variables that were statistically significantly associated with a COPD diagnosis. After adjusting for covariates, anticholinergic bronchodilators (OR = 3.336) and tobacco cessation counseling (OR = 2.871) were found to have a large influence on the model. The final predictive model had an AUC of 0.754, sensitivity of 60%, specificity of 78%, PPV of 73%, and an NPV of 66%. This claims-based predictive model provides an acceptable level of accuracy in identifying patients likely to have undiagnosed COPD in a large national health plan. Identification of patients with undiagnosed COPD may enable timely management and lead to improved health outcomes and reduced COPD-related health care expenditures.

  1. Framing health for land-use planning legislation: A qualitative descriptive content analysis.

    PubMed

    Harris, Patrick; Kent, Jennifer; Sainsbury, Peter; Thow, Anne Marie

    2016-01-01

    Framing health as a relevant policy issue for other sectors is not well understood. A recent review of the New South Wales (Australia) land-use planning system resulted in the drafting of legislation with an internationally unprecedented focus on human health. We apply a political science approach to investigate the question 'how and to what extent were health and wider issues framed in submissions to the review?' We investigated a range of stakeholder submissions including health focussed agencies (n = 31), purposively identified key stakeholders with influence on the review (n = 24), and a random sample of other agencies and individuals (n = 47). Using qualitative descriptive analysis we inductively coded for the term 'health' and sub-categories. We deductively coded for 'wider concerns' using a locally endorsed 'Healthy Urban Development Checklist'. Additional inductive analysis uncovered further 'wider concerns'. Health was explicitly identified as a relevant issue for planning policy only in submissions by health-focussed agencies. This framing concerned the new planning system promoting and protecting health as well as connecting health to wider planning concerns including economic issues, transport, public open space and, to a slightly lesser extent, environmental sustainability. Key stakeholder and other agency submissions focussed on these and other wider planning concerns but did not mention health in detail. Health agency submissions did not emphasise infrastructure, density or housing as explicitly as others. Framing health as a relevant policy issue has the potential to influence legislative change governing the business of other sectors. Without submissions from health agencies arguing the importance of having health as an objective in the proposed legislation it is unlikely health considerations would have gained prominence in the draft bill. The findings have implications for health agency engagement with legislative change processes and beyond in land use planning. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. A method for acquiring random range uncertainty probability distributions in proton therapy

    NASA Astrophysics Data System (ADS)

    Holloway, S. M.; Holloway, M. D.; Thomas, S. J.

    2018-01-01

    In treatment planning we depend upon accurate knowledge of geometric and range uncertainties. If the uncertainty model is inaccurate then the plan will produce under-dosing of the target and/or overdosing of OAR. We aim to provide a method for which centre and site-specific population range uncertainty due to inter-fraction motion can be quantified to improve the uncertainty model in proton treatment planning. Daily volumetric MVCT data from previously treated radiotherapy patients has been used to investigate inter-fraction changes to water equivalent path-length (WEPL). Daily image-guidance scans were carried out for each patient and corrected for changes in CTV position (using rigid transformations). An effective depth algorithm was used to determine residual range changes, after corrections had been applied, throughout the treatment by comparing WEPL within the CTV at each fraction for several beam angles. As a proof of principle this method was used to quantify uncertainties for inter-fraction range changes for a sample of head and neck patients of Σ=3.39 mm, σ = 4.72 mm and overall mean = -1.82 mm. For prostate Σ=5.64 mm, σ = 5.91 mm and overall mean = 0.98 mm. The choice of beam angle for head and neck did not affect the inter-fraction range error significantly; however this was not the same for prostate. Greater range changes were seen using a lateral beam compared to an anterior beam for prostate due to relative motion of the prostate and femoral heads. A method has been developed to quantify population range changes due to inter-fraction motion that can be adapted for the clinic. The results of this work highlight the importance of robust planning and analysis in proton therapy. Such information could be used in robust optimisation algorithms or treatment plan robustness analysis. Such knowledge will aid in establishing beam start conditions at planning and for establishing adaptive planning protocols.

  3. An impact evaluation of Plan Indonesia's early childhood program.

    PubMed

    Aboud, Frances E; Proulx, Kerrie; Asrilla, Zaitu

    2016-12-27

    High-quality preschools are known to prepare children for success in primary school. Over half of Indonesia's children now pass through preschools whose quality and effectiveness are unknown. Our goal was to evaluate two government preschool models, namely kindergarten (TK) and the less formal health-post (PAUD), with and without capacity-building efforts of a non-governmental organization (NGO-Plan), on children's language and math skills. Thirteen TK and 17 PAUD Plan-supported and the same number of government-supported preschools were randomly selected from East Nusa Tenggara, Indonesia. Five children from each (n = 292) and five who had graduated from each and were now in first grade (n = 241) were randomly selected and tested on language and math measures. The Plan-supported preschools were assessed for quality. Mothers reported on their family's socio-demographic situation and their child's preventive health practices, illnesses and diet over the previous two weeks. Analyses of covariance adjusting for clusters indicated that children attending Plan-supported preschools performed better overall, and especially those in TK preschools. Plan-supported TKs were observed to have higher quality than Plan-supported PAUDs. First graders who graduated from Plan-supported preschools, both TK and PAUD, achieved higher scores on language and math tests than government-supported graduates. Preventive health practices were better in the Plan group, though diet and height-for-age were poor overall. Upgrades to the government preschool program are needed to raise its quality and effectiveness, specifically by introducing a mix of instructional and indoor free-choice play, resources and teacher training to support children's learning.

  4. RandomSpot: A web-based tool for systematic random sampling of virtual slides.

    PubMed

    Wright, Alexander I; Grabsch, Heike I; Treanor, Darren E

    2015-01-01

    This paper describes work presented at the Nordic Symposium on Digital Pathology 2014, Linköping, Sweden. Systematic random sampling (SRS) is a stereological tool, which provides a framework to quickly build an accurate estimation of the distribution of objects or classes within an image, whilst minimizing the number of observations required. RandomSpot is a web-based tool for SRS in stereology, which systematically places equidistant points within a given region of interest on a virtual slide. Each point can then be visually inspected by a pathologist in order to generate an unbiased sample of the distribution of classes within the tissue. Further measurements can then be derived from the distribution, such as the ratio of tumor to stroma. RandomSpot replicates the fundamental principle of traditional light microscope grid-shaped graticules, with the added benefits associated with virtual slides, such as facilitated collaboration and automated navigation between points. Once the sample points have been added to the region(s) of interest, users can download the annotations and view them locally using their virtual slide viewing software. Since its introduction, RandomSpot has been used extensively for international collaborative projects, clinical trials and independent research projects. So far, the system has been used to generate over 21,000 sample sets, and has been used to generate data for use in multiple publications, identifying significant new prognostic markers in colorectal, upper gastro-intestinal and breast cancer. Data generated using RandomSpot also has significant value for training image analysis algorithms using sample point coordinates and pathologist classifications.

  5. SNP selection and classification of genome-wide SNP data using stratified sampling random forests.

    PubMed

    Wu, Qingyao; Ye, Yunming; Liu, Yang; Ng, Michael K

    2012-09-01

    For high dimensional genome-wide association (GWA) case-control data of complex disease, there are usually a large portion of single-nucleotide polymorphisms (SNPs) that are irrelevant with the disease. A simple random sampling method in random forest using default mtry parameter to choose feature subspace, will select too many subspaces without informative SNPs. Exhaustive searching an optimal mtry is often required in order to include useful and relevant SNPs and get rid of vast of non-informative SNPs. However, it is too time-consuming and not favorable in GWA for high-dimensional data. The main aim of this paper is to propose a stratified sampling method for feature subspace selection to generate decision trees in a random forest for GWA high-dimensional data. Our idea is to design an equal-width discretization scheme for informativeness to divide SNPs into multiple groups. In feature subspace selection, we randomly select the same number of SNPs from each group and combine them to form a subspace to generate a decision tree. The advantage of this stratified sampling procedure can make sure each subspace contains enough useful SNPs, but can avoid a very high computational cost of exhaustive search of an optimal mtry, and maintain the randomness of a random forest. We employ two genome-wide SNP data sets (Parkinson case-control data comprised of 408 803 SNPs and Alzheimer case-control data comprised of 380 157 SNPs) to demonstrate that the proposed stratified sampling method is effective, and it can generate better random forest with higher accuracy and lower error bound than those by Breiman's random forest generation method. For Parkinson data, we also show some interesting genes identified by the method, which may be associated with neurological disorders for further biological investigations.

  6. Material hardship and children's social-emotional development: Testing mitigating effects of Child Development Accounts in a randomized experiment.

    PubMed

    Huang, J; Kim, Y; Sherraden, M

    2017-01-01

    Research has established a negative association between household material hardship and children's mental health. This study examines whether Child Development Accounts (CDAs), an economic intervention that encourages families to accumulate assets for children's long-term development, mitigate the association between material hardship and children's social-emotional development. Researchers conducted a randomized experiment of CDAs in Oklahoma, USA, with a probability sample (N = 7328) of all infants born in two 3-month periods in 2007. After agreeing to participate in the experiment, caregivers of 2704 infants completed a baseline survey and were assigned randomly to the treatment (n = 1358) or control group (n = 1346). The intervention exposed the treatment group to a CDA, which consisted of an Oklahoma 529 College Savings Plan account, financial incentives and financial information. Material hardship has a negative association with the social-emotional development of children around the age of 4 years. Estimates from regression analysis indicate that CDAs mitigate about 50% of the negative association between material hardship and children's social-emotional development. Although they do not provide direct support for consumption in households experiencing material hardship, CDAs may improve child development by influencing parenting practices and parents' expectations for their children. We discuss the implications of using asset-building programmes to improve child development. © 2016 John Wiley & Sons Ltd.

  7. Motivational interviewing and intimate partner violence: a randomized trial.

    PubMed

    Saftlas, Audrey F; Harland, Karisa K; Wallis, Anne B; Cavanaugh, Joseph; Dickey, Penny; Peek-Asa, Corinne

    2014-02-01

    To determine if motivational interviewing (MI) improves self-efficacy (primary outcome), depressive symptoms (secondary outcome), and stage-of-readiness-to-change (secondary outcome) among women in abusive relationships. Randomized controlled trial among women who experienced intimate partner violence in a current relationship over the past 12 months. Subjects were recruited from two family planning clinics (December 2007 to May 2010). The intervention included an initial face-to-face session and three telephone sessions administered 1-, 2-, and 4-months postenrollment, each using MI to identify personal goals. Controls were referred to community-based resources. Outcomes were measured by self-administered questionnaires before randomization and 6 months later. Modified intent-to-treat analyses of completed participants were conducted using multivariate analysis of variance for continuous outcomes and polytomous logistic regression for categorical outcomes. Three hundred six eligible women were enrolled (recruitment rate = 64%); 204 completed the 6-month follow-up (completion rate = 67%). Depressive symptoms decreased to a greater extent in MI than referral women (P = .07). Self-efficacy and stage-of-readiness-to-change increased more in MI than referral women, but these differences were not statistically significant. With a lower than projected sample size, our findings did not achieve statistical significance at the 5% level but suggest a beneficial effect of the MI intervention on reducing depressive symptoms. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Reinforcing integrated psychiatric service attendance in an opioid-agonist program: a randomized and controlled trial.

    PubMed

    Kidorf, Michael; Brooner, Robert K; Gandotra, Neeraj; Antoine, Denis; King, Van L; Peirce, Jessica; Ghazarian, Sharon

    2013-11-01

    The benefits of integrating substance abuse and psychiatric care may be limited by poor service utilization. This randomized clinical trial evaluated the efficacy of using contingency management to improve utilization of psychiatric services co-located and integrated within a community-based methadone maintenance treatment program. Opioid-dependent outpatients (n=125) with any current psychiatric disorder were randomly assigned to: (1) reinforced on-site integrated care (ROIC), with vouchers (worth $25.00) contingent on full adherence to each week of scheduled psychiatric services; or (2) standard on-site integrated care (SOIC). All participants received access to the same schedule of psychiatrist and mental health counseling sessions for 12-weeks. ROIC participants attended more overall psychiatric sessions at month 1 (M=7.53 vs. 3.97, p<.001), month 2 (M=6.31 vs. 2.81, p<.001), and month 3 (M=5.71 vs. 2.44, p<.001). Both conditions evidenced reductions in psychiatric distress (p<.001) and similar rates of drug-positive urine samples. No differences in study retention were observed. These findings suggest that contingency management can improve utilization of psychiatric services scheduled within an on-site and integrated treatment model. Delivering evidenced-based mental health counseling, or modifying the contingency plan to include illicit drug use, may be required to facilitate greater changes in psychiatric and substance abuse outcomes. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Visceral larvae as a predictive index of the overall level of fish batch infection in European anchovies (Engraulis encrasicolus): A rapid procedure for Food Business Operators to assess marketability.

    PubMed

    Guardone, L; Nucera, D; Pergola, V; Costanzo, F; Costa, E; Tinacci, L; Guidi, A; Armani, A

    2017-06-05

    The European anchovy (Engraulis encrasicolus), one of the most important pelagic fish resources in the Mediterranean Sea, is frequently infected by anisakid larvae. Food Business Operators (FBOs) should use appropriate sampling plans and analytical methods to avoid commercialization of massively infected batches and reduce the risk of transmission of viable zoonotic larvae. In this study, performed at FishLab (Department of Veterinary Sciences of the University of Pisa) during 2016, an official sampling plan was associated with a digestion protocol for the inspection of anchovies. Considering that anisakid larvae are usually located in the fish visceral cavity and in the adjacent muscles (VM), this part was analyzed. In particular, we assessed the reliability of the digestion of a subsample of 150g (±30g) of VM, randomly collected from 29 specimens, in estimating the marketability of the anchovies' batch. Fifty-seven samples of 29 anchovies were collected. Each anchovy was sectioned to separate VM. All the subsamples were digested, and visible larvae counted. A high correlation between the number of larvae in VM regions and in the total batch was observed, indicating a very significant contribution of the VM region on total number of parasites. The Mean Abundance (MA) was used to assess the batch marketability according to a threshold calculated on the basis of the maximum number of nematodes tolerated per sample. Considering that the MA can be calculated only when the number of examined specimens is known, the number of visible Larvae per gram of tissue (LpG) was calculated on 150g (±30g) of VM subsamples. A LpG marketability threshold was calculated dividing the maximum number of tolerated nematodes by the average weight of a sample of 29 anchovies calculated considering data available in literature. To evaluate the diagnostic performance of the LpG threshold, the marketability of 57 batches assessed on the basis of the MA threshold was assumed as the gold standard. The proposed LpG showed very high Specificity and Sensitivity. These findings suggest that the analysis of VM is representative of the overall infestation of the batch, both when considering the absolute number of parasites and the LpG, and may represent a valid alternative to the whole anchovy digestion. In particular, the use of an automated digestive method, coupled with the aforesaid sampling plan, could allow the procedure to be used by FBOs in operational conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Prevalence of infraocclusion of primary molars determined using a new 2D image analysis methodology.

    PubMed

    Odeh, R; Mihailidis, S; Townsend, G; Lähdesmäki, R; Hughes, T; Brook, A

    2016-06-01

    The reported prevalence of infraocclusion varies widely, reflecting differences in definitions and measurement/scoring approaches. This study aimed to quantify the prevalence and extent of infraocclusion in singletons and twins during the late mixed dentition stage of dental development using a new diagnostic imaging method and objective criteria. The study also aimed to determine any associations between infraocclusion and gender, arch type, arch side and tooth type. Two samples were analysed, 1454 panoramic radiographs of singletons and 270 dental models of twins. Both samples ranged in age from 8 to 11 years. Adobe Photoshop CS5 was used to measure the extent of infraocclusion. Repeatability tests showed systematic and random errors were small. The prevalence in the maxilla was low (<1%), whereas the prevalence in the mandible was 22% in the singleton sample and 32% in the twin sample. The primary mandibular first molar was affected more often than the second molar. There was no significant difference in the expression between genders or sides. A new technique for measuring infraocclusion has been developed with high intra- and interoperator reproducibility. This method should enhance early diagnosis of tooth developmental abnormalities and treatment planning during the late mixed dentition stage of development. © 2016 Australian Dental Association.

  11. Factors associated with chronic diseases among the elderly receiving treatment under the Family Health Strategy.

    PubMed

    Pimenta, Fernanda Batista; Pinho, Lucinéia; Silveira, Marise Fagundes; Botelho, Ana Cristina de Carvalho

    2015-08-01

    The profile of a sample population of elderly receiving treatment under the Family Health Strategy in the municipality of Teófilo Otoni, State of Minas Gerais, Brazil, is described, and the factors associated with diseases prevalence examined. Using simple random sampling, 385 elderly were interviewed using Form A and Elderly Form from the Primary Health Care Information System. The majority of the sample (83.1%) self-reported at least one disease, 69.9% had hypertension, and 17.7% had diabetes. Poisson regression analysis showed that the main factors associated with hypertension and other diseases were being non-white, having a low level of education, medication use, dental prosthesis use, and lack of a private health plan. The prevalence of diabetes was greater among women and individuals who depended on other people to live. It can be concluded that this sample population of elderly has a generally low socioeconomic status and are more susceptible to developing diseases, particularly hypertension. Diabetes should be controlled although had relatively low prevalence. It is suggested investments in structuring the health system network to provide adequate care for the elderly and in training health professionals to play an effective role in improving the quality of life of the elderly in Brazil.

  12. Experimental validation of the van Herk margin formula for lung radiation therapy

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

    Ecclestone, Gillian; Heath, Emily; Bissonnette, Jean-Pierre

    2013-11-15

    Purpose: To validate the van Herk margin formula for lung radiation therapy using realistic dose calculation algorithms and respiratory motion modeling. The robustness of the margin formula against variations in lesion size, peak-to-peak motion amplitude, tissue density, treatment technique, and plan conformity was assessed, along with the margin formula assumption of a homogeneous dose distribution with perfect plan conformity.Methods: 3DCRT and IMRT lung treatment plans were generated within the ORBIT treatment planning platform (RaySearch Laboratories, Sweden) on 4DCT datasets of virtual phantoms. Random and systematic respiratory motion induced errors were simulated using deformable registration and dose accumulation tools available withinmore » ORBIT for simulated cases of varying lesion sizes, peak-to-peak motion amplitudes, tissue densities, and plan conformities. A detailed comparison between the margin formula dose profile model, the planned dose profiles, and penumbra widths was also conducted to test the assumptions of the margin formula. Finally, a correction to account for imperfect plan conformity was tested as well as a novel application of the margin formula that accounts for the patient-specific motion trajectory.Results: The van Herk margin formula ensured full clinical target volume coverage for all 3DCRT and IMRT plans of all conformities with the exception of small lesions in soft tissue. No dosimetric trends with respect to plan technique or lesion size were observed for the systematic and random error simulations. However, accumulated plans showed that plan conformity decreased with increasing tumor motion amplitude. When comparing dose profiles assumed in the margin formula model to the treatment plans, discrepancies in the low dose regions were observed for the random and systematic error simulations. However, the margin formula respected, in all experiments, the 95% dose coverage required for planning target volume (PTV) margin derivation, as defined by the ICRU; thus, suitable PTV margins were estimated. The penumbra widths calculated in lung tissue for each plan were found to be very similar to the 6.4 mm value assumed by the margin formula model. The plan conformity correction yielded inconsistent results which were largely affected by image and dose grid resolution while the trajectory modified PTV plans yielded a dosimetric benefit over the standard internal target volumes approach with up to a 5% decrease in the V20 value.Conclusions: The margin formula showed to be robust against variations in tumor size and motion, treatment technique, plan conformity, as well as low tissue density. This was validated by maintaining coverage of all of the derived PTVs by 95% dose level, as required by the formal definition of the PTV. However, the assumption of perfect plan conformity in the margin formula derivation yields conservative margin estimation. Future modifications to the margin formula will require a correction for plan conformity. Plan conformity can also be improved by using the proposed trajectory modified PTV planning approach. This proves especially beneficial for tumors with a large anterior–posterior component of respiratory motion.« less

  13. Effects of Emergent Literacy Interventions for Preschoolers with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Hudson, Roxanne F.; Sanders, Elizabeth A.; Greenway, Rosanne; Xie, Sharon; Smith, Maya; Gasamis, Colin; Martini, Jay; Schwartz, Ilene; Hackett, Jacob

    2017-01-01

    Combining data from a series of three planned consecutive randomized controlled trials, the present study investigates two literacy interventions for preschool children with autism spectrum disorder. For the first cohort, children were randomized to interactive book reading (IBR; treatment) or business as usual (BAU; control); in Cohort 2,…

  14. Randomized Controlled Trial of Video Self-Modeling Following Speech Restructuring Treatment for Stuttering

    ERIC Educational Resources Information Center

    Cream, Angela; O'Brian, Sue; Jones, Mark; Block, Susan; Harrison, Elisabeth; Lincoln, Michelle; Hewat, Sally; Packman, Ann; Menzies, Ross; Onslow, Mark

    2010-01-01

    Purpose: In this study, the authors investigated the efficacy of video self-modeling (VSM) following speech restructuring treatment to improve the maintenance of treatment effects. Method: The design was an open-plan, parallel-group, randomized controlled trial. Participants were 89 adults and adolescents who undertook intensive speech…

  15. Intraclass Correlations and Covariate Outcome Correlations for Planning Two-and Three-Level Cluster-Randomized Experiments in Education

    ERIC Educational Resources Information Center

    Hedges, Larry V.; Hedberg, E. C.

    2013-01-01

    Background: Cluster-randomized experiments that assign intact groups such as schools or school districts to treatment conditions are increasingly common in educational research. Such experiments are inherently multilevel designs whose sensitivity (statistical power and precision of estimates) depends on the variance decomposition across levels.…

  16. Intraclass Correlations and Covariate Outcome Correlations for Planning 2 and 3 Level Cluster Randomized Experiments in Education

    ERIC Educational Resources Information Center

    Hedges, Larry V.; Hedberg, Eric C.

    2013-01-01

    Background: Cluster randomized experiments that assign intact groups such as schools or school districts to treatment conditions are increasingly common in educational research. Such experiments are inherently multilevel designs whose sensitivity (statistical power and precision of estimates) depends on the variance decomposition across levels.…

  17. Steinhaus’ Geometric Location Problem for Random Samples in the Plane.

    DTIC Science & Technology

    1982-05-11

    NAL 411R A1, ’I 7 - I STEINHAUS ’ GEOMETRIC LOCATION PROBLEM FOR RANDOM SAMPLES IN THE PLANE By Dorit Hochbaum and J. Michael Steele TECHNICAL REPORT...DEPARTMENT OF STATISTICS -Dltrib’ytion/ STANFORD UNIVERSITY A-I.abilty Codes STANFORD, CALIFORNIA Dist Spciat ecial Steinhaus ’ Geometric Location Problem for...Random Samples in the Plane By Dorit Hochbaum and J. Michael Steele I. Introduction. The work of H. Steinhaus U wf94 as apparently the first explicit

  18. Timely and complete publication of economic evaluations alongside randomized controlled trials.

    PubMed

    Thorn, Joanna C; Noble, Sian M; Hollingworth, William

    2013-01-01

    Little is known about the extent and nature of publication bias in economic evaluations. Our objective was to determine whether economic evaluations are subject to publication bias by considering whether economic data are as likely to be reported, and reported as promptly, as effectiveness data. Trials that intended to conduct an economic analysis and ended before 2008 were identified in the International Standard Randomised Controlled Trial Number (ISRCTN) register; a random sample of 100 trials was retrieved. Fifty comparator trials were randomly drawn from those not identified as intending to conduct an economic study. The trial start and end dates, estimated sample size and funder type were extracted. For trials planning economic evaluations, effectiveness and economic publications were sought; publication dates and journal impact factors were extracted. Effectiveness abstracts were assessed for whether they reached a firm conclusion that one intervention was most effective. Primary investigators were contacted about reasons for non-publication of results, or reasons for differential publication strategies for effectiveness and economic results. Trials planning an economic study were more likely to be funded by government (p = 0.01) and larger (p = 0.003) than other trials. The trials planning an economic evaluation had a mean of 6.5 (range 2.7-13.2) years since the trial end in which to publish their results. Effectiveness results were reported by 70 %, while only 43 % published economic evaluations (p < 0.001). Reasons for non-publication of economic results included the intervention being ineffective, and staffing issues. Funding source, time since trial end and length of study were not associated with a higher probability of publishing the economic evaluation. However, studies that were small or of unknown size were significantly less likely to publish economic evaluations than large studies (p < 0.001). The authors' confidence in labelling one intervention clearly most effective did not affect the probability of publication. The mean time to publication was 0.7 years longer for cost-effectiveness data than for effectiveness data where both were published (p = 0.001). The median journal impact factor was 1.6 points higher for effectiveness publications than for the corresponding economic publications (p = 0.01). Reasons for publishing in different journals included editorial decision making and the additional time that economic evaluation takes to conduct. Trials that intend to conduct an economic analysis are less likely to report economic data than effectiveness data. Where economic results do appear, they are published later, and in journals with lower impact factors. These results suggest that economic output may be more susceptible than effectiveness data to publication bias. Funders, grant reviewers and trialists themselves should ensure economic evaluations are prioritized and adequately staffed to avoid potential problems with bias.

  19. Unmet Needs of Family Planning Among Women: A Cross-Sectional Study in a Rural Area of Kanchipuram District, Tamil Nadu, South India.

    PubMed

    Vishnu Prasad, R; Venkatachalam, J; Singh, Zile

    2016-10-01

    Global contraceptive usage was 63.3 % in 2010 which was 9 % more than that in 1990. NFHS-III 2005-2006 revealed that the contraceptive prevalence rate was 56 % while in the past decade it was 48 %. In India, female sterilization is the most commonly preferred method of contraception accounting for 76 %, while in Tamil Nadu it was 90 %. Thus, this study aims at measuring the prevalence of unmet needs of family planning and its determinants in a rural area of Kancheepuram district, Tamil Nadu. The study was carried out as a community-based cross-sectional study in Chunambed panchayat, a rural area in Kanchipuram District, Tamil Nadu, India, among 505 women of age group 15-49 years. Cluster random sampling was done to select the households to include in the study. In every household, all the available and eligible women were explained about the study and recruited after obtaining informed consent. Chi-square test was applied for finding the difference in proportion, and p value <0.05 was considered statistically significant. The prevalence of unmet need for family planning in our study population was nearly 31 %; it was even more for younger age groups and for the women whose family size was less. 51.7 % of the participants were currently using a contraceptive measure and very few of their partners used contraception. Government health facilities were the major source of contraceptive service and majority of our participants were well aware about the various contraceptive methods. Unmet needs of family planning were high in our study population, and the knowledge about the contraceptive use and family planning was found to be fairly adequate.

  20. Tales from the New Frontier: Pioneers' Experiences with Consumer-Driven Health Care

    PubMed Central

    Lo Sasso, Anthony T; Rice, Thomas; Gabel, Jon R; Whitmore, Heidi

    2004-01-01

    Objective To conduct site visits to study the early experiences of firms offering consumer-driven health care (CDHC) plans to their employees and firms that provide CDHC products. Data Sources/Study Setting A convenience sample of three firms offering CDHC products to their employees, one of which is also a large insurer, and one firm offering an early CDHC product to employers. Study Design We conducted onsite interviews of four companies during the spring and summer of 2003. These four cases were not selected randomly. We contacted organizations that already had a consumer-driven plan in place by January 2002 so as to provide a complete year's worth of experience with CDHC. Principal Findings The experience of the companies we visited indicated that favorable selection tends to result when a CDHC plan is introduced alongside traditional preferred provider organization (PPO) and health maintenance organization (HMO) plan offerings. Two sites demonstrated substantial cost-savings. Our case studies also indicate that the more mundane aspects of health care benefits are still crucial under CDHC. The size of the provider network accessible through the CDHC plan was critical, as was the role of premium contributions in the benefit design. Also, companies highlighted the importance of educating employees about new CDHC products: employees who understood the product were more likely to enroll. Conclusions Our site visits suggest the peril (risk selection) and the promise (cost savings) of CDHC. At this point there is still far more that we do not know about CDHC than we do know. Little is known about the extent to which CDHC changes people's behavior, the extent to which quality of care is affected by CDHC, and whether web-based information and tools actually make patients become better consumers. PMID:15230912

  1. Tales from the new frontier: pioneers' experiences with consumer-driven health care.

    PubMed

    Lo Sasso, Anthony T; Rice, Thomas; Gabel, Jon R; Whitmore, Heidi

    2004-08-01

    To conduct site visits to study the early experiences of firms offering consumer-driven health care (CDHC) plans to their employees and firms that provide CDHC products. A convenience sample of three firms offering CDHC products to their employees, one of which is also a large insurer, and one firm offering an early CDHC product to employers. We conducted onsite interviews of four companies during the spring and summer of 2003. These four cases were not selected randomly. We contacted organizations that already had a consumer-driven plan in place by January 2002 so as to provide a complete year's worth of experience with CDHC. The experience of the companies we visited indicated that favorable selection tends to result when a CDHC plan is introduced alongside traditional preferred provider organization (PPO) and health maintenance organization (HMO) plan offerings. Two sites demonstrated substantial cost-savings. Our case studies also indicate that the more mundane aspects of health care benefits are still crucial under CDHC. The size of the provider network accessible through the CDHC plan was critical, as was the role of premium contributions in the benefit design. Also, companies highlighted the importance of educating employees about new CDHC products: employees who understood the product were more likely to enroll. Our site visits suggest the peril (risk selection) and the promise (cost savings) of CDHC. At this point there is still far more that we do not know about CDHC than we do know. Little is known about the extent to which CDHC changes people's behavior, the extent to which quality of care is affected by CDHC, and whether web-based information and tools actually make patients become better consumers.

  2. Quality of radiotherapy reporting in randomized controlled trials of prostate cancer.

    PubMed

    Soon, Yu Yang; Chen, Desiree; Tan, Teng Hwee; Tey, Jeremy

    2018-06-07

    Good radiotherapy reporting in clinical trials of prostate radiotherapy is important because it will allow accurate reproducibility of radiotherapy treatment and minimize treatment variations that can affect patient outcomes. The aim of our study is to assess the quality of prostate radiotherapy (RT) treatment reporting in randomized controlled trials in prostate cancer. We searched MEDLINE for randomized trials of prostate cancer, published from 1996 to 2016 and included prostate RT as one of the intervention arms. We assessed if the investigators reported the ten criteria adequately in the trial reports: RT dose prescription method; RT dose-planning procedures; organs at risk (OAR) dose constraints; target volume definition, simulation procedures; treatment verification procedures; total RT dose; fractionation schedule; conduct of quality assurance (QA) as well as presence or absence of deviations in RT treatment planning and delivery. We performed multivariate logistic regression to determine the factors that may influence the quality of reporting. We found 59 eligible trials. There was significant variability in the quality of reporting. Target volume definition, total RT dose and fractionation schedule were reported adequately in 97% of included trials. OAR constraints, simulation procedures and presence or absence of deviations in RT treatment planning and delivery were reported adequately in 30% of included trials. Twenty-four trials (40%) reported seven criteria or more adequately. Multivariable logistic analysis showed that trials that published their quality assurance results and cooperative group trials were more likely to have adequate quality in reporting in at least seven criteria. There is significant variability in the quality of reporting on prostate radiotherapy treatment in randomized trials of prostate cancer. We need to have consensus guidelines to standardize the reporting of radiotherapy treatment in randomized trials.

  3. Methods for a multicenter randomized trial for mixed urinary incontinence: rationale and patient-centeredness of the ESTEEM trial.

    PubMed

    Sung, Vivian W; Borello-France, Diane; Dunivan, Gena; Gantz, Marie; Lukacz, Emily S; Moalli, Pamela; Newman, Diane K; Richter, Holly E; Ridgeway, Beri; Smith, Ariana L; Weidner, Alison C; Meikle, Susan

    2016-10-01

    Mixed urinary incontinence (MUI) can be a challenging condition to manage. We describe the protocol design and rationale for the Effects of Surgical Treatment Enhanced with Exercise for Mixed Urinary Incontinence (ESTEEM) trial, designed to compare a combined conservative and surgical treatment approach versus surgery alone for improving patient-centered MUI outcomes at 12 months. ESTEEM is a multisite, prospective, randomized trial of female participants with MUI randomized to a standardized perioperative behavioral/pelvic floor exercise intervention plus midurethral sling versus midurethral sling alone. We describe our methods and four challenges encountered during the design phase: defining the study population, selecting relevant patient-centered outcomes, determining sample size estimates using a patient-reported outcome measure, and designing an analysis plan that accommodates MUI failure rates. A central theme in the design was patient centeredness, which guided many key decisions. Our primary outcome is patient-reported MUI symptoms measured using the Urogenital Distress Inventory (UDI) score at 12 months. Secondary outcomes include quality of life, sexual function, cost-effectiveness, time to failure, and need for additional treatment. The final study design was implemented in November 2013 across eight clinical sites in the Pelvic Floor Disorders Network. As of 27 February 2016, 433 total/472 targeted participants had been randomized. We describe the ESTEEM protocol and our methods for reaching consensus for methodological challenges in designing a trial for MUI by maintaining the patient perspective at the core of key decisions. This trial will provide information that can directly impact patient care and clinical decision making.

  4. Assessing the effectiveness and cost-effectiveness of audit and feedback on physician’s prescribing indicators: study protocol of a randomized controlled trial with economic evaluation

    PubMed Central

    2012-01-01

    Background Physician prescribing is the most frequent medical intervention with a highest impact on healthcare costs and outcomes. Therefore improving and promoting rational drug use is a great interest. We aimed to assess the effectiveness and cost-effectiveness of two forms of conducting prescribing audit and feedback interventions and a printed educational material intervention in improving physician prescribing. Method/design A four-arm randomized trial with economic evaluation will be conducted in Tehran. Three interventions (routine feedback, revised feedback, and printed educational material) and a no intervention control arm will be compared. Physicians working in outpatient practices are randomly allocated to one of the four arms using stratified randomized sampling. The interventions are developed based on a review of literature, physician interviews, current experiences in Iran and with theoretical insights from the Theory of Planned Behavior. Effects of the interventions on improving antibiotics and corticosteroids prescribing will be assessed in regression analyses. Cost data will be assessed from a health care provider’s perspective and incremental cost-effectiveness ratios will be calculated. Discussion This study will determine the effectiveness and cost-effectiveness of three interventions and allow us to determine the most effective interventions in improving prescribing pattern. If the interventions are cost-effective, they will likely be applied nationwide. Trial registration Iranian Registry of Clinical Trials Registration Number: IRCT201106086740N1Pharmaceutical Sciences Research Center of TUMS Ethics Committee Registration Number: 90-02-27-07 PMID:23351564

  5. Reducing seed dependent variability of non-uniformly sampled multidimensional NMR data

    NASA Astrophysics Data System (ADS)

    Mobli, Mehdi

    2015-07-01

    The application of NMR spectroscopy to study the structure, dynamics and function of macromolecules requires the acquisition of several multidimensional spectra. The one-dimensional NMR time-response from the spectrometer is extended to additional dimensions by introducing incremented delays in the experiment that cause oscillation of the signal along "indirect" dimensions. For a given dimension the delay is incremented at twice the rate of the maximum frequency (Nyquist rate). To achieve high-resolution requires acquisition of long data records sampled at the Nyquist rate. This is typically a prohibitive step due to time constraints, resulting in sub-optimal data records to the detriment of subsequent analyses. The multidimensional NMR spectrum itself is typically sparse, and it has been shown that in such cases it is possible to use non-Fourier methods to reconstruct a high-resolution multidimensional spectrum from a random subset of non-uniformly sampled (NUS) data. For a given acquisition time, NUS has the potential to improve the sensitivity and resolution of a multidimensional spectrum, compared to traditional uniform sampling. The improvements in sensitivity and/or resolution achieved by NUS are heavily dependent on the distribution of points in the random subset acquired. Typically, random points are selected from a probability density function (PDF) weighted according to the NMR signal envelope. In extreme cases as little as 1% of the data is subsampled. The heavy under-sampling can result in poor reproducibility, i.e. when two experiments are carried out where the same number of random samples is selected from the same PDF but using different random seeds. Here, a jittered sampling approach is introduced that is shown to improve random seed dependent reproducibility of multidimensional spectra generated from NUS data, compared to commonly applied NUS methods. It is shown that this is achieved due to the low variability of the inherent sensitivity of the random subset chosen from a given PDF. Finally, it is demonstrated that metrics used to find optimal NUS distributions are heavily dependent on the inherent sensitivity of the random subset, and such optimisation is therefore less critical when using the proposed sampling scheme.

  6. Use of Matrix Sampling Procedures to Assess Achievement in Solving Open Addition and Subtraction Sentences.

    ERIC Educational Resources Information Center

    Montague, Margariete A.

    This study investigated the feasibility of concurrently and randomly sampling examinees and items in order to estimate group achievement. Seven 32-item tests reflecting a 640-item universe of simple open sentences were used such that item selection (random, systematic) and assignment (random, systematic) of items (four, eight, sixteen) to forms…

  7. Improving Generalizations from Experiments Using Propensity Score Subclassification: Assumptions, Properties, and Contexts

    ERIC Educational Resources Information Center

    Tipton, Elizabeth

    2013-01-01

    As a result of the use of random assignment to treatment, randomized experiments typically have high internal validity. However, units are very rarely randomly selected from a well-defined population of interest into an experiment; this results in low external validity. Under nonrandom sampling, this means that the estimate of the sample average…

  8. Stratification of American hearing aid users by age and audiometric characteristics: a method for representative sampling.

    PubMed

    Aronoff, Justin M; Yoon, Yang-soo; Soli, Sigfrid D

    2010-06-01

    Stratified sampling plans can increase the accuracy and facilitate the interpretation of a dataset characterizing a large population. However, such sampling plans have found minimal use in hearing aid (HA) research, in part because of a paucity of quantitative data on the characteristics of HA users. The goal of this study was to devise a quantitatively derived stratified sampling plan for HA research, so that such studies will be more representative and generalizable, and the results obtained using this method are more easily reinterpreted as the population changes. Pure-tone average (PTA) and age information were collected for 84,200 HAs acquired in 2006 and 2007. The distribution of PTA and age was quantified for each HA type and for a composite of all HA users. Based on their respective distributions, PTA and age were each divided into three groups, the combination of which defined the stratification plan. The most populous PTA and age group was also subdivided, allowing greater homogeneity within strata. Finally, the percentage of users in each stratum was calculated. This article provides a stratified sampling plan for HA research, based on a quantitative analysis of the distribution of PTA and age for HA users. Adopting such a sampling plan will make HA research results more representative and generalizable. In addition, data acquired using such plans can be reinterpreted as the HA population changes.

  9. Quality of family planning services in primary health centers of Jimma Zone, Southwest Ethiopia.

    PubMed

    Tafese, Fikru; Woldie, Mirkuzie; Megerssa, Berhane

    2013-11-01

    Good quality of care in family planning (FP) services help individuals and couples to meet their reproductive health needs safely and effectively. Therefore, assessment and improvement of the quality of family planning services could enhance family planning services utilization. This study was thus conducted to assess the quality of family planning services in primary health centers of Jimma Zone, Southwest Ethiopia. A cross-sectional facility based study was conducted from March 1(st)-25(th), 2011 among family planning clients of government primary health care centers in southwest Ethiopia. Exit interview of 301 family planning clients identified through systematic random sampling technique was carried out using a pre-tested structured questionnaire. Availability of resources was checked using provider interview and inventory checklist. Moreover, a total of 150 consultation sessions were observed using checklist. Descriptive statistics and linear regression coefficients were generated to meet the objective of the study. There was a shortage of some medical equipment, trained staffs, and information education and communication materials (IEC) in all of the family planning clinics. The mean waiting time at the service delivery points and consultation duration were 16.4 and 10.5 minutes, respectively. The providers used at least one information education and communication material in 33.3% of the consultation sessions. The overall satisfaction score was 8.64. Clients' perception on adequacy of information during consultation (β=0.24; ( 95%CI=0.02-0.16) ease of getting the clinic site, short waiting time (β=0.17; 95%CI=0.15-029) and educational level (β=0.09; 95%CI =0.09-0.29) were significantly associated with overall satisfaction. The findings of this study showed that there was lack of critical resources for the provision of quality family planning services in all of the primary health care centers included in the study. This has affected important aspects of service provision including the use of IEC materials during consultations. Hence, it is advisable that health managers of the health facilities and the district health office ensure improved availability of trained personnel, IEC materials and other supplies at the clinics.

  10. 40 CFR 761.306 - Sampling 1 meter square surfaces by random selection of halves.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Sampling 1 meter square surfaces by...(b)(3) § 761.306 Sampling 1 meter square surfaces by random selection of halves. (a) Divide each 1 meter square portion where it is necessary to collect a surface wipe test sample into two equal (or as...

  11. 40 CFR 761.306 - Sampling 1 meter square surfaces by random selection of halves.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Sampling 1 meter square surfaces by...(b)(3) § 761.306 Sampling 1 meter square surfaces by random selection of halves. (a) Divide each 1 meter square portion where it is necessary to collect a surface wipe test sample into two equal (or as...

  12. 40 CFR 761.306 - Sampling 1 meter square surfaces by random selection of halves.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Sampling 1 meter square surfaces by...(b)(3) § 761.306 Sampling 1 meter square surfaces by random selection of halves. (a) Divide each 1 meter square portion where it is necessary to collect a surface wipe test sample into two equal (or as...

  13. 40 CFR 761.306 - Sampling 1 meter square surfaces by random selection of halves.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Sampling 1 meter square surfaces by...(b)(3) § 761.306 Sampling 1 meter square surfaces by random selection of halves. (a) Divide each 1 meter square portion where it is necessary to collect a surface wipe test sample into two equal (or as...

  14. 40 CFR 761.306 - Sampling 1 meter square surfaces by random selection of halves.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sampling 1 meter square surfaces by...(b)(3) § 761.306 Sampling 1 meter square surfaces by random selection of halves. (a) Divide each 1 meter square portion where it is necessary to collect a surface wipe test sample into two equal (or as...

  15. Science: Curriculum Guide for Teaching Gifted Children Science in Grades One Through Three: A Sample Ecology Unit.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Office of Curriculum Services.

    The natural science curriculum guide for gifted primary students includes a sample teaching-learning plan for an ecology unit and eight sample lesson plans. Chapter One provides an overview of the unit, a review of behavioral objectives, and a list of concepts and generalizations. The second chapter cites a teaching-learning plan dealing with such…

  16. 40 CFR Appendix X to Part 86 - Sampling Plans for Selective Enforcement Auditing of Heavy-Duty Engines and Light-Duty Trucks

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Sampling Plans for Selective Enforcement Auditing of Heavy-Duty Engines and Light-Duty Trucks X Appendix X to Part 86 Protection of... AND IN-USE HIGHWAY VEHICLES AND ENGINES Pt. 86, App. X Appendix X to Part 86—Sampling Plans for...

  17. Psychological empowerment and job satisfaction between Baby Boomer and Generation X nurses.

    PubMed

    Sparks, Amy M

    2012-05-01

    This paper is a report of a study of differences in nurses' generational psychological empowerment and job satisfaction. Generations differ in work styles such as autonomy, work ethics, involvement, views on leadership, and primary views on what constitutes innovation, quality, and service. A secondary analysis was conducted from two data sets resulting in a sample of 451 registered nurses employed at five hospitals in West Virginia. One data set was gathered from a convenience sample and one from a randomly selected sample. Data were collected from 2000 to 2004. Baby Boomer nurses reported higher mean total psychological empowerment scores than Generation X nurses. There were no differences in total job satisfaction scores between the generations. There were significant differences among the generations' psychological empowerment scores. Generational differences related to psychological empowerment could provide insight into inconsistent findings related to nurse job satisfaction. Nurse administrators may consider this evidence when working on strategic plans to motivate and entice Generation X nurses and retain Baby Boomers. Although implications based on this study are tentative, the results indicate the need for administrators to consider the differences between Baby Boomer and Generation X nurses. © 2011 Blackwell Publishing Ltd.

  18. Drivers’ Visual Behavior-Guided RRT Motion Planner for Autonomous On-Road Driving

    PubMed Central

    Du, Mingbo; Mei, Tao; Liang, Huawei; Chen, Jiajia; Huang, Rulin; Zhao, Pan

    2016-01-01

    This paper describes a real-time motion planner based on the drivers’ visual behavior-guided rapidly exploring random tree (RRT) approach, which is applicable to on-road driving of autonomous vehicles. The primary novelty is in the use of the guidance of drivers’ visual search behavior in the framework of RRT motion planner. RRT is an incremental sampling-based method that is widely used to solve the robotic motion planning problems. However, RRT is often unreliable in a number of practical applications such as autonomous vehicles used for on-road driving because of the unnatural trajectory, useless sampling, and slow exploration. To address these problems, we present an interesting RRT algorithm that introduces an effective guided sampling strategy based on the drivers’ visual search behavior on road and a continuous-curvature smooth method based on B-spline. The proposed algorithm is implemented on a real autonomous vehicle and verified against several different traffic scenarios. A large number of the experimental results demonstrate that our algorithm is feasible and efficient for on-road autonomous driving. Furthermore, the comparative test and statistical analyses illustrate that its excellent performance is superior to other previous algorithms. PMID:26784203

  19. Drivers' Visual Behavior-Guided RRT Motion Planner for Autonomous On-Road Driving.

    PubMed

    Du, Mingbo; Mei, Tao; Liang, Huawei; Chen, Jiajia; Huang, Rulin; Zhao, Pan

    2016-01-15

    This paper describes a real-time motion planner based on the drivers' visual behavior-guided rapidly exploring random tree (RRT) approach, which is applicable to on-road driving of autonomous vehicles. The primary novelty is in the use of the guidance of drivers' visual search behavior in the framework of RRT motion planner. RRT is an incremental sampling-based method that is widely used to solve the robotic motion planning problems. However, RRT is often unreliable in a number of practical applications such as autonomous vehicles used for on-road driving because of the unnatural trajectory, useless sampling, and slow exploration. To address these problems, we present an interesting RRT algorithm that introduces an effective guided sampling strategy based on the drivers' visual search behavior on road and a continuous-curvature smooth method based on B-spline. The proposed algorithm is implemented on a real autonomous vehicle and verified against several different traffic scenarios. A large number of the experimental results demonstrate that our algorithm is feasible and efficient for on-road autonomous driving. Furthermore, the comparative test and statistical analyses illustrate that its excellent performance is superior to other previous algorithms.

  20. Repeated Random Sampling in Year 5

    ERIC Educational Resources Information Center

    Watson, Jane M.; English, Lyn D.

    2016-01-01

    As an extension to an activity introducing Year 5 students to the practice of statistics, the software "TinkerPlots" made it possible to collect repeated random samples from a finite population to informally explore students' capacity to begin reasoning with a distribution of sample statistics. This article provides background for the…

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