SU-F-P-20: Predicting Waiting Times in Radiation Oncology Using Machine Learning
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joseph, A; Herrera, D; Hijal, T
Purpose: Waiting times remain one of the most vexing patient satisfaction challenges facing healthcare. Waiting time uncertainty can cause patients, who are already sick or in pain, to worry about when they will receive the care they need. These waiting periods are often difficult for staff to predict and only rough estimates are typically provided based on personal experience. This level of uncertainty leaves most patients unable to plan their calendar, making the waiting experience uncomfortable, even painful. In the present era of electronic health records (EHRs), waiting times need not be so uncertain. Extensive EHRs provide unprecedented amounts ofmore » data that can statistically cluster towards representative values when appropriate patient cohorts are selected. Predictive modelling, such as machine learning, is a powerful approach that benefits from large, potentially complex, datasets. The essence of machine learning is to predict future outcomes by learning from previous experience. The application of a machine learning algorithm to waiting time data has the potential to produce personalized waiting time predictions such that the uncertainty may be removed from the patient’s waiting experience. Methods: In radiation oncology, patients typically experience several types of waiting (eg waiting at home for treatment planning, waiting in the waiting room for oncologist appointments and daily waiting in the waiting room for radiotherapy treatments). A daily treatment wait time model is discussed in this report. To develop a prediction model using our large dataset (with more than 100k sample points) a variety of machine learning algorithms from the Python package sklearn were tested. Results: We found that the Random Forest Regressor model provides the best predictions for daily radiotherapy treatment waiting times. Using this model, we achieved a median residual (actual value minus predicted value) of 0.25 minutes and a standard deviation residual of 6.5 minutes. This means that the majority of our estimates are within 6.5 minutes of the actual wait time. Conclusion: The goal of this project was to define an appropriate machine learning algorithm to estimate waiting times based on the collective knowledge and experience learned from previous patients. Our results offer an opportunity to improve the information that is provided to patients and family members regarding the amount of time they can expect to wait for radiotherapy treatment at our centre. AJ acknowledges support by the CREATE Medical Physics Research Training Network grant of the Natural Sciences and Engineering Research Council (Grant number: 432290) and from the 2014 Q+ Initiative of the McGill University Health Centre.« less
Backfilling with guarantees granted upon job submission.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leung, Vitus Joseph; Bunde, David P.; Lindsay, Alexander M.
2011-01-01
In this paper, we present scheduling algorithms that simultaneously support guaranteed starting times and favor jobs with system desired traits. To achieve the first of these goals, our algorithms keep a profile with potential starting times for every unfinished job and never move these starting times later, just as in Conservative Backfilling. To achieve the second, they exploit previously unrecognized flexibility in the handling of holes opened in this profile when jobs finish early. We find that, with one choice of job selection function, our algorithms can consistently yield a lower average waiting time than Conservative Backfilling while still providingmore » a guaranteed start time to each job as it arrives. In fact, in most cases, the algorithms give a lower average waiting time than the more aggressive EASY backfilling algorithm, which does not provide guaranteed start times. Alternately, with a different choice of job selection function, our algorithms can focus the benefit on the widest submitted jobs, the reason for the existence of parallel systems. In this case, these jobs experience significantly lower waiting time than Conservative Backfilling with minimal impact on other jobs.« less
Ren, Tao; Zhang, Chuan; Lin, Lin; Guo, Meiting; Xie, Xionghang
2014-01-01
We address the scheduling problem for a no-wait flow shop to optimize total completion time with release dates. With the tool of asymptotic analysis, we prove that the objective values of two SPTA-based algorithms converge to the optimal value for sufficiently large-sized problems. To further enhance the performance of the SPTA-based algorithms, an improvement scheme based on local search is provided for moderate scale problems. New lower bound is presented for evaluating the asymptotic optimality of the algorithms. Numerical simulations demonstrate the effectiveness of the proposed algorithms.
Ren, Tao; Zhang, Chuan; Lin, Lin; Guo, Meiting; Xie, Xionghang
2014-01-01
We address the scheduling problem for a no-wait flow shop to optimize total completion time with release dates. With the tool of asymptotic analysis, we prove that the objective values of two SPTA-based algorithms converge to the optimal value for sufficiently large-sized problems. To further enhance the performance of the SPTA-based algorithms, an improvement scheme based on local search is provided for moderate scale problems. New lower bound is presented for evaluating the asymptotic optimality of the algorithms. Numerical simulations demonstrate the effectiveness of the proposed algorithms. PMID:24764774
NASA Astrophysics Data System (ADS)
Swaraj Pati, Mythili N.; Korde, Pranav; Dey, Pallav
2017-11-01
The purpose of this paper is to introduce an optimised variant to the round robin scheduling algorithm. Every algorithm works in its own way and has its own merits and demerits. The proposed algorithm overcomes the shortfalls of the existing scheduling algorithms in terms of waiting time, turnaround time, throughput and number of context switches. The algorithm is pre-emptive and works based on the priority of the associated processes. The priority is decided on the basis of the remaining burst time of a particular process, that is; lower the burst time, higher the priority and higher the burst time, lower the priority. To complete the execution, a time quantum is initially specified. In case if the burst time of a particular process is less than 2X of the specified time quantum but more than 1X of the specified time quantum; the process is given high priority and is allowed to execute until it completes entirely and finishes. Such processes do not have to wait for their next burst cycle.
Poster - 26: Electronic Waiting Room Management for a busy Cancer Centre
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kildea, John; Hijal, Tarek
We describe an electronic waiting room management system that we have developed and deployed in our cancer centre. Our system connects with our electronic medical records systems, gathers data for a machine learning algorithm to predict future patient waiting times, and is integrated with a mobile phone app. The system has been in operation for over nine months and has led to reduced lines, calmer waiting rooms and overwhelming patient and staff satisfaction.
The PROCARE consortium: toward an improved allocation strategy for kidney allografts.
Otten, H G; Joosten, I; Allebes, W A; van der Meer, A; Hilbrands, L B; Baas, M; Spierings, E; Hack, C E; van Reekum, F; van Zuilen, A D; Verhaar, M C; Bots, M L; Seelen, M A J; Sanders, J S F; Hepkema, B G; Lambeck, A J; Bungener, L B; Roozendaal, C; Tilanus, M G J; Vanderlocht, J; Voorter, C E; Wieten, L; van Duijnhoven, E; Gelens, M; Christiaans, M; van Ittersum, F; Nurmohamed, A; Lardy, N M; Swelsen, W T; van Donselaar-van der Pant, K A M I; van der Weerd, N C; Ten Berge, I J M; Bemelman, F J; Hoitsma, A J; de Fijter, J W; Betjes, M G H; Roelen, D L; Claas, F H J
2014-10-01
Kidney transplantation is the best treatment option for patients with end-stage renal failure. At present, approximately 800 Dutch patients are registered on the active waiting list of Eurotransplant. The waiting time in the Netherlands for a kidney from a deceased donor is on average between 3 and 4 years. During this period, patients are fully dependent on dialysis, which replaces only partly the renal function, whereas the quality of life is limited. Mortality among patients on the waiting list is high. In order to increase the number of kidney donors, several initiatives have been undertaken by the Dutch Kidney Foundation including national calls for donor registration and providing information on organ donation and kidney transplantation. The aim of the national PROCARE consortium is to develop improved matching algorithms that will lead to a prolonged survival of transplanted donor kidneys and a reduced HLA immunization. The latter will positively affect the waiting time for a retransplantation. The present algorithm for allocation is among others based on matching for HLA antigens, which were originally defined by antibodies using serological typing techniques. However, several studies suggest that this algorithm needs adaptation and that other immune parameters which are currently not included may assist in improving graft survival rates. We will employ a multicenter-based evaluation on 5429 patients transplanted between 1995 and 2005 in the Netherlands. The association between key clinical endpoints and selected laboratory defined parameters will be examined, including Luminex-defined HLA antibody specificities, T and B cell epitopes recognized on the mismatched HLA antigens, non-HLA antibodies, and also polymorphisms in complement and Fc receptors functionally associated with effector functions of anti-graft antibodies. From these data, key parameters determining the success of kidney transplantation will be identified which will lead to the identification of additional parameters to be included in future matching algorithms aiming to extend survival of transplanted kidneys and to diminish HLA immunization. Computer simulation studies will reveal the number of patients having a direct benefit from improved matching, the effect on shortening of the waiting list, and the decrease in waiting time. Copyright © 2014. Published by Elsevier B.V.
Parallel-Batch Scheduling and Transportation Coordination with Waiting Time Constraint
Gong, Hua; Chen, Daheng; Xu, Ke
2014-01-01
This paper addresses a parallel-batch scheduling problem that incorporates transportation of raw materials or semifinished products before processing with waiting time constraint. The orders located at the different suppliers are transported by some vehicles to a manufacturing facility for further processing. One vehicle can load only one order in one shipment. Each order arriving at the facility must be processed in the limited waiting time. The orders are processed in batches on a parallel-batch machine, where a batch contains several orders and the processing time of the batch is the largest processing time of the orders in it. The goal is to find a schedule to minimize the sum of the total flow time and the production cost. We prove that the general problem is NP-hard in the strong sense. We also demonstrate that the problem with equal processing times on the machine is NP-hard. Furthermore, a dynamic programming algorithm in pseudopolynomial time is provided to prove its ordinarily NP-hardness. An optimal algorithm in polynomial time is presented to solve a special case with equal processing times and equal transportation times for each order. PMID:24883385
Hansoti, Bhakti; Jenson, Alexander; Kironji, Antony G; Katz, Joanne; Levin, Scott; Rothman, Richard; Kelen, Gabor D; Wallis, Lee A
2017-01-01
In low resource settings, an inadequate number of trained healthcare workers and high volumes of children presenting to Primary Healthcare Centers (PHC) result in prolonged waiting times and significant delays in identifying and evaluating critically ill children. The Sick Children Require Emergency Evaluation Now (SCREEN) program, a simple six-question screening algorithm administered by lay healthcare workers, was developed in 2014 to rapidly identify critically ill children and to expedite their care at the point of entry into a clinic. We sought to determine the impact of SCREEN on waiting times for critically ill children post real world implementation in Cape Town, South Africa. This is a prospective, observational implementation-effectiveness hybrid study that sought to determine: (1) the impact of SCREEN implementation on waiting times as a primary outcome measure, and (2) the effectiveness of the SCREEN tool in accurately identifying critically ill children when utilised by the QM and adherence by the QM to the SCREEN algorithm as secondary outcome measures. The study was conducted in two phases, Phase I control (pre-SCREEN implementation- three months in 2014) and Phase II (post-SCREEN implementation-two distinct three month periods in 2016). In Phase I, 1600 (92.38%) of 1732 children presenting to 4 clinics, had sufficient data for analysis and comprised the control sample. In Phase II, all 3383 of the children presenting to the 26 clinics during the sampling time frame had sufficient data for analysis. The proportion of critically ill children who saw a professional nurse within 10 minutes increased tenfold from 6.4% to 64% (Phase I to Phase II) with the median time to seeing a professional nurse reduced from 100.3 minutes to 4.9 minutes, (p < .001, respectively). Overall layperson screening compared to Integrated Management of Childhood Illnesses (IMCI) designation by a nurse had a sensitivity of 94.2% and a specificity of 88.1%, despite large variance in adherence to the SCREEN algorithm across clinics. The SCREEN program when implemented in a real-world setting can significantly reduce waiting times for critically ill children in PHCs, however further work is required to improve the implementation of this innovative program.
Act-and-wait time-delayed feedback control of autonomous systems
NASA Astrophysics Data System (ADS)
Pyragas, Viktoras; Pyragas, Kestutis
2018-02-01
Recently an act-and-wait modification of time-delayed feedback control has been proposed for the stabilization of unstable periodic orbits in nonautonomous dynamical systems (Pyragas and Pyragas, 2016 [30]). The modification implies a periodic switching of the feedback gain and makes the closed-loop system finite-dimensional. Here we extend this modification to autonomous systems. In order to keep constant the phase difference between the controlled orbit and the act-and-wait switching function an additional small-amplitude periodic perturbation is introduced. The algorithm can stabilize periodic orbits with an odd number of real unstable Floquet exponents using a simple single-input single-output constraint control.
Operating room scheduling using hybrid clustering priority rule and genetic algorithm
NASA Astrophysics Data System (ADS)
Santoso, Linda Wahyuni; Sinawan, Aisyah Ashrinawati; Wijaya, Andi Rahadiyan; Sudiarso, Andi; Masruroh, Nur Aini; Herliansyah, Muhammad Kusumawan
2017-11-01
Operating room is a bottleneck resource in most hospitals so that operating room scheduling system will influence the whole performance of the hospitals. This research develops a mathematical model of operating room scheduling for elective patients which considers patient priority with limit number of surgeons, operating rooms, and nurse team. Clustering analysis was conducted to the data of surgery durations using hierarchical and non-hierarchical methods. The priority rule of each resulting cluster was determined using Shortest Processing Time method. Genetic Algorithm was used to generate daily operating room schedule which resulted in the lowest values of patient waiting time and nurse overtime. The computational results show that this proposed model reduced patient waiting time by approximately 32.22% and nurse overtime by approximately 32.74% when compared to actual schedule.
Burst wait time simulation of CALIBAN reactor at delayed super-critical state
DOE Office of Scientific and Technical Information (OSTI.GOV)
Humbert, P.; Authier, N.; Richard, B.
2012-07-01
In the past, the super prompt critical wait time probability distribution was measured on CALIBAN fast burst reactor [4]. Afterwards, these experiments were simulated with a very good agreement by solving the non-extinction probability equation [5]. Recently, the burst wait time probability distribution has been measured at CEA-Valduc on CALIBAN at different delayed super-critical states [6]. However, in the delayed super-critical case the non-extinction probability does not give access to the wait time distribution. In this case it is necessary to compute the time dependent evolution of the full neutron count number probability distribution. In this paper we present themore » point model deterministic method used to calculate the probability distribution of the wait time before a prescribed count level taking into account prompt neutrons and delayed neutron precursors. This method is based on the solution of the time dependent adjoint Kolmogorov master equations for the number of detections using the generating function methodology [8,9,10] and inverse discrete Fourier transforms. The obtained results are then compared to the measurements and Monte-Carlo calculations based on the algorithm presented in [7]. (authors)« less
More Effective Distributed ML via a Stale Synchronous Parallel Parameter Server
Ho, Qirong; Cipar, James; Cui, Henggang; Kim, Jin Kyu; Lee, Seunghak; Gibbons, Phillip B.; Gibson, Garth A.; Ganger, Gregory R.; Xing, Eric P.
2014-01-01
We propose a parameter server system for distributed ML, which follows a Stale Synchronous Parallel (SSP) model of computation that maximizes the time computational workers spend doing useful work on ML algorithms, while still providing correctness guarantees. The parameter server provides an easy-to-use shared interface for read/write access to an ML model’s values (parameters and variables), and the SSP model allows distributed workers to read older, stale versions of these values from a local cache, instead of waiting to get them from a central storage. This significantly increases the proportion of time workers spend computing, as opposed to waiting. Furthermore, the SSP model ensures ML algorithm correctness by limiting the maximum age of the stale values. We provide a proof of correctness under SSP, as well as empirical results demonstrating that the SSP model achieves faster algorithm convergence on several different ML problems, compared to fully-synchronous and asynchronous schemes. PMID:25400488
Scheduling Jobs with Variable Job Processing Times on Unrelated Parallel Machines
Zhang, Guang-Qian; Wang, Jian-Jun; Liu, Ya-Jing
2014-01-01
m unrelated parallel machines scheduling problems with variable job processing times are considered, where the processing time of a job is a function of its position in a sequence, its starting time, and its resource allocation. The objective is to determine the optimal resource allocation and the optimal schedule to minimize a total cost function that dependents on the total completion (waiting) time, the total machine load, the total absolute differences in completion (waiting) times on all machines, and total resource cost. If the number of machines is a given constant number, we propose a polynomial time algorithm to solve the problem. PMID:24982933
Renewal processes based on generalized Mittag-Leffler waiting times
NASA Astrophysics Data System (ADS)
Cahoy, Dexter O.; Polito, Federico
2013-03-01
The fractional Poisson process has recently attracted experts from several fields of study. Its natural generalization of the ordinary Poisson process made the model more appealing for real-world applications. In this paper, we generalized the standard and fractional Poisson processes through the waiting time distribution, and showed their relations to an integral operator with a generalized Mittag-Leffler function in the kernel. The waiting times of the proposed renewal processes have the generalized Mittag-Leffler and stretched-squashed Mittag-Leffler distributions. Note that the generalizations naturally provide greater flexibility in modeling real-life renewal processes. Algorithms to simulate sample paths and to estimate the model parameters are derived. Note also that these procedures are necessary to make these models more usable in practice. State probabilities and other qualitative or quantitative features of the models are also discussed.
Job-shop scheduling applied to computer vision
NASA Astrophysics Data System (ADS)
Sebastian y Zuniga, Jose M.; Torres-Medina, Fernando; Aracil, Rafael; Reinoso, Oscar; Jimenez, Luis M.; Garcia, David
1997-09-01
This paper presents a method for minimizing the total elapsed time spent by n tasks running on m differents processors working in parallel. The developed algorithm not only minimizes the total elapsed time but also reduces the idle time and waiting time of in-process tasks. This condition is very important in some applications of computer vision in which the time to finish the total process is particularly critical -- quality control in industrial inspection, real- time computer vision, guided robots. The scheduling algorithm is based on the use of two matrices, obtained from the precedence relationships between tasks, and the data obtained from the two matrices. The developed scheduling algorithm has been tested in one application of quality control using computer vision. The results obtained have been satisfactory in the application of different image processing algorithms.
Sheehan, Katie J; Sobolev, Boris; Guy, Pierre; Bohm, Eric; Hellsten, Erik; Sutherland, Jason M; Kuramoto, Lisa; Jaglal, Susan
2016-02-01
Episodes of care defined by the event of hip fracture surgery are widely used for the assessment of surgical wait times and outcomes. However, this approach does not consider nonoperative deaths, implying that survival time begins at the time of procedure. This approach makes treatment effect implicitly conditional on surviving to treatment. The purpose of this article is to describe a novel conceptual framework for constructing an episode of hip fracture care to fully evaluate the incidence of adverse events related to time after admission for hip fracture. This admission-based approach enables the assessment of the full harm of delay by including deaths while waiting for surgery, not just deaths after surgery. Some patients wait until their conditions are optimized for surgery, whereas others have to wait until surgical service becomes available. We provide definitions, linkage rules, and algorithms to capture all hip fracture patients and events other than surgery. Finally, we discuss data elements for stratifying patients according to administrative factors for delay to allow researchers and policymakers to determine who will benefit most from expedited access to surgery. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.
An optimal general type-2 fuzzy controller for Urban Traffic Network.
Khooban, Mohammad Hassan; Vafamand, Navid; Liaghat, Alireza; Dragicevic, Tomislav
2017-01-01
Urban traffic network model is illustrated by state-charts and object-diagram. However, they have limitations to show the behavioral perspective of the Traffic Information flow. Consequently, a state space model is used to calculate the half-value waiting time of vehicles. In this study, a combination of the general type-2 fuzzy logic sets and the Modified Backtracking Search Algorithm (MBSA) techniques are used in order to control the traffic signal scheduling and phase succession so as to guarantee a smooth flow of traffic with the least wait times and average queue length. The parameters of input and output membership functions are optimized simultaneously by the novel heuristic algorithm MBSA. A comparison is made between the achieved results with those of optimal and conventional type-1 fuzzy logic controllers. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.
Path statistics, memory, and coarse-graining of continuous-time random walks on networks
Kion-Crosby, Willow; Morozov, Alexandre V.
2015-01-01
Continuous-time random walks (CTRWs) on discrete state spaces, ranging from regular lattices to complex networks, are ubiquitous across physics, chemistry, and biology. Models with coarse-grained states (for example, those employed in studies of molecular kinetics) or spatial disorder can give rise to memory and non-exponential distributions of waiting times and first-passage statistics. However, existing methods for analyzing CTRWs on complex energy landscapes do not address these effects. Here we use statistical mechanics of the nonequilibrium path ensemble to characterize first-passage CTRWs on networks with arbitrary connectivity, energy landscape, and waiting time distributions. Our approach can be applied to calculating higher moments (beyond the mean) of path length, time, and action, as well as statistics of any conservative or non-conservative force along a path. For homogeneous networks, we derive exact relations between length and time moments, quantifying the validity of approximating a continuous-time process with its discrete-time projection. For more general models, we obtain recursion relations, reminiscent of transfer matrix and exact enumeration techniques, to efficiently calculate path statistics numerically. We have implemented our algorithm in PathMAN (Path Matrix Algorithm for Networks), a Python script that users can apply to their model of choice. We demonstrate the algorithm on a few representative examples which underscore the importance of non-exponential distributions, memory, and coarse-graining in CTRWs. PMID:26646868
Near-optimal reconfiguration and maintenance of close spacecraft formations.
Lovell, T A; Tragesser, S G
2004-05-01
This paper investigates orbit guidance algorithms for formation flying experiments. The relative motion of one satellite about a reference satellite is formulated in terms of a set of parameters that clearly describe the size, shape, and orientation of the formation. A nominal three-impulse burn maneuver algorithm is presented that is applicable for both reconfiguration and maintenance of spacecraft formations. Two methods of implementing the algorithm are discussed, one involving fixed times between each burn and one allowing the wait times to vary. The implications of employing four or more impulses for maneuvers are assessed. Examples applying the algorithm to various formation scenarios are presented, along with practical implications of each result.
Chen, Lei; Welsh, Kerry J; Chang, Brian; Kidd, Laura; Kott, Marylee; Zare, Mohammad; Carroll, Kelley; Nguyen, Andy; Wahed, Amer; Tholpady, Ashok; Pung, Norin; McKee, Donna; Risin, Semyon A; Hunter, Robert L
2016-09-01
Harris Health System (HHS) is a safety net system providing health care to the underserved of Harris County, Texas. There was a 6-month waiting period for a rheumatologist consult for patients with suspected systemic lupus erythematosus (SLE). The objective of the intervention was to improve access to specialty care. An algorithmic approach to testing for SLE was implemented initially through the HHS referral center. The algorithm was further offered as a "one-click" order for physicians, with automated reflex testing, interpretation, and case triaging by clinical pathology. Data review revealed that prior to the intervention, 80% of patients did not have complete laboratory workups available at the first rheumatology visit. Implementation of algorithmic testing and triaging of referrals by pathologists resulted in decreasing the waiting time for a rheumatologist by 50%. Clinical pathology intervention and case triaging can improve access to care in a county health care system. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
DOT National Transportation Integrated Search
2015-05-01
This is the Final Report for the FRATIS Dallas-Fort Worth DFW prototype system. The FRATIS prototype in DFW consisted of the following components: optimization algorithm, terminal wait time, route specific navigation/traffic/weather, and advanced not...
DOT National Transportation Integrated Search
2015-03-01
This document describes the As-Built System Architecture and Design for the FRATIS Dallas-Fort Worth DFW prototype system. The FRATIS prototype in DFW consisted of the following components: optimization algorithm, terminal wait time, route specific n...
Hybrid deterministic/stochastic simulation of complex biochemical systems.
Lecca, Paola; Bagagiolo, Fabio; Scarpa, Marina
2017-11-21
In a biological cell, cellular functions and the genetic regulatory apparatus are implemented and controlled by complex networks of chemical reactions involving genes, proteins, and enzymes. Accurate computational models are indispensable means for understanding the mechanisms behind the evolution of a complex system, not always explored with wet lab experiments. To serve their purpose, computational models, however, should be able to describe and simulate the complexity of a biological system in many of its aspects. Moreover, it should be implemented by efficient algorithms requiring the shortest possible execution time, to avoid enlarging excessively the time elapsing between data analysis and any subsequent experiment. Besides the features of their topological structure, the complexity of biological networks also refers to their dynamics, that is often non-linear and stiff. The stiffness is due to the presence of molecular species whose abundance fluctuates by many orders of magnitude. A fully stochastic simulation of a stiff system is computationally time-expensive. On the other hand, continuous models are less costly, but they fail to capture the stochastic behaviour of small populations of molecular species. We introduce a new efficient hybrid stochastic-deterministic computational model and the software tool MoBioS (MOlecular Biology Simulator) implementing it. The mathematical model of MoBioS uses continuous differential equations to describe the deterministic reactions and a Gillespie-like algorithm to describe the stochastic ones. Unlike the majority of current hybrid methods, the MoBioS algorithm divides the reactions' set into fast reactions, moderate reactions, and slow reactions and implements a hysteresis switching between the stochastic model and the deterministic model. Fast reactions are approximated as continuous-deterministic processes and modelled by deterministic rate equations. Moderate reactions are those whose reaction waiting time is greater than the fast reaction waiting time but smaller than the slow reaction waiting time. A moderate reaction is approximated as a stochastic (deterministic) process if it was classified as a stochastic (deterministic) process at the time at which it crosses the threshold of low (high) waiting time. A Gillespie First Reaction Method is implemented to select and execute the slow reactions. The performances of MoBios were tested on a typical example of hybrid dynamics: that is the DNA transcription regulation. The simulated dynamic profile of the reagents' abundance and the estimate of the error introduced by the fully deterministic approach were used to evaluate the consistency of the computational model and that of the software tool.
An Efficient Randomized Algorithm for Real-Time Process Scheduling in PicOS Operating System
NASA Astrophysics Data System (ADS)
Helmy*, Tarek; Fatai, Anifowose; Sallam, El-Sayed
PicOS is an event-driven operating environment designed for use with embedded networked sensors. More specifically, it is designed to support the concurrency in intensive operations required by networked sensors with minimal hardware requirements. Existing process scheduling algorithms of PicOS; a commercial tiny, low-footprint, real-time operating system; have their associated drawbacks. An efficient, alternative algorithm, based on a randomized selection policy, has been proposed, demonstrated, confirmed for efficiency and fairness, on the average, and has been recommended for implementation in PicOS. Simulations were carried out and performance measures such as Average Waiting Time (AWT) and Average Turn-around Time (ATT) were used to assess the efficiency of the proposed randomized version over the existing ones. The results prove that Randomized algorithm is the best and most attractive for implementation in PicOS, since it is most fair and has the least AWT and ATT on average over the other non-preemptive scheduling algorithms implemented in this paper.
Bungard, Tammy J; Smigorowsky, Marcie J; Lalonde, Lucille D; Hogan, Terry; Doliszny, Katharine M; Gebreyesus, Ghirmay; Garg, Sipi; Archer, Stephen L
2009-01-01
BACKGROUND: Universal access to health care is valued in Canada but increasing wait times for services (eg, cardiology consultation) raise safety questions. Observations suggest that deficiencies in the process of care contribute to wait times. Consequently, an outpatient clinic was designed for Ensuring Access and Speedy Evaluation (Cardiac EASE) in a university group practice, providing cardiac consultative services for northern Alberta. Cardiac EASE has two components: a single-point-of-entry intake service (prospective testing using physician-approved algorithms and previsit triage) and a multidisciplinary clinic (staffed by cardiologists, nurse practitioners and doctoral-trained pharmacists). OBJECTIVES: It was hypothesized that Cardiac EASE would reduce the time to initial consultation and a definitive diagnosis, and also increase the referral capacity. METHODS: The primary and secondary outcomes were time from referral to initial consultation, and time to achieve a definitive diagnosis and management plan, respectively. A conventionally managed historical control group (three-month pre-EASE period in 2003) was compared with the EASE group (2004 to 2006). The conventional referral mechanism continued concurrently with EASE. RESULTS: A comparison between pre-EASE (n=311) and EASE (n=3096) revealed no difference in the mean (± SD) age (60±16 years), sex (55% and 52% men, respectively) or reason for referral, including chest pain (31% and 40%, respectively) and arrhythmia (27% and 29%, respectively). Cardiac EASE reduced the time to initial cardiac consultation (from 71±45 days to 33±19 days) and time to a definitive diagnosis (from 120±86 days to 51±58 days) (P<0.0001). The annual number of new referrals increased from 1512 in 2002 to 2574 in 2006 due to growth in the Cardiac EASE clinic. The number of patients seen through the conventional referral mechanism and their wait times remained constant during the study period. CONCLUSIONS: Cardiac EASE reduced wait times, increased capacity and shortened time to achieve a diagnosis. The EASE model could shorten wait times for consultative services in Canada. PMID:19960130
Algorithm for prioritization of patients on the waiting list for liver transplantation.
Gambato, M; Senzolo, M; Canova, D; Germani, G; Tomat, S; Masier, A; Russo, F P; Perissinotto, E; Zanus, G; Cillo, U; Burra, P
2007-01-01
Prioritization of patients on the waiting list (WL) for OLT is still a critical issue. Numerous models have been developed to predict mortality before and after OLT. The aim of the study was to prospectively evaluate cirrhotics with and without hepatocellular carcinoma (HCC) undergoing orthotopic liver transplantation (OLT) severity of liver disease on the WL and at transplant, mortality on the WL and after OLT, and their correlations. An algorithm based on seven patient variables (MELD, CTP, UNOS, HCC, BMI, waiting time, age) was created by software dedicated to prioritize patients on the waiting list. We evaluated 118 patients including 75 men and 43 women of age range 19 to 66 years, who underwent OLT from July 2004 to June 2006. Mean CTP and MELD at listing were 8.44 (range 6-12) and 13 (range 2-24), respectively. Overall mortality on the WL at 24 months was 13%, which was significantly higher among patients with MELD > 25 compared to patients with MELD 0 to 15 (P < .0001) or MELD 16 to 25 (P = .0007) at listing. Mean MELD at OLT was 15 (range 7-36), which was significantly lower in patients with than without HCC (MELD 12 vs 16; P = .0003). Six hundred-day patient survival was significantly lower among patients with MELD > 25 compared to patients with MELD < 25 at OLT (P = .017), whereas no difference in survival was observed between patients with and without HCC. The sickest patients are characterized by high mortality both on the waiting list and after liver transplantation. Patients with HCC are transplanted in better condition compared to patients without HCC with the same survival.
NASA Astrophysics Data System (ADS)
Santosa, B.; Siswanto, N.; Fiqihesa
2018-04-01
This paper proposes a discrete Particle Swam Optimization (PSO) to solve limited-wait hybrid flowshop scheduing problem with multi objectives. Flow shop schedulimg represents the condition when several machines are arranged in series and each job must be processed at each machine with same sequence. The objective functions are minimizing completion time (makespan), total tardiness time, and total machine idle time. Flow shop scheduling model always grows to cope with the real production system accurately. Since flow shop scheduling is a NP-Hard problem then the most suitable method to solve is metaheuristics. One of metaheuristics algorithm is Particle Swarm Optimization (PSO), an algorithm which is based on the behavior of a swarm. Originally, PSO was intended to solve continuous optimization problems. Since flow shop scheduling is a discrete optimization problem, then, we need to modify PSO to fit the problem. The modification is done by using probability transition matrix mechanism. While to handle multi objectives problem, we use Pareto Optimal (MPSO). The results of MPSO is better than the PSO because the MPSO solution set produced higher probability to find the optimal solution. Besides the MPSO solution set is closer to the optimal solution
Disk storage management for LHCb based on Data Popularity estimator
NASA Astrophysics Data System (ADS)
Hushchyn, Mikhail; Charpentier, Philippe; Ustyuzhanin, Andrey
2015-12-01
This paper presents an algorithm providing recommendations for optimizing the LHCb data storage. The LHCb data storage system is a hybrid system. All datasets are kept as archives on magnetic tapes. The most popular datasets are kept on disks. The algorithm takes the dataset usage history and metadata (size, type, configuration etc.) to generate a recommendation report. This article presents how we use machine learning algorithms to predict future data popularity. Using these predictions it is possible to estimate which datasets should be removed from disk. We use regression algorithms and time series analysis to find the optimal number of replicas for datasets that are kept on disk. Based on the data popularity and the number of replicas optimization, the algorithm minimizes a loss function to find the optimal data distribution. The loss function represents all requirements for data distribution in the data storage system. We demonstrate how our algorithm helps to save disk space and to reduce waiting times for jobs using this data.
Tang, Wenming; Liu, Guixiong; Li, Yuzhong; Tan, Daji
2017-01-01
High data transmission efficiency is a key requirement for an ultrasonic phased array with multi-group ultrasonic sensors. Here, a novel FIFOs scheduling algorithm was proposed and the data transmission efficiency with hardware technology was improved. This algorithm includes FIFOs as caches for the ultrasonic scanning data obtained from the sensors with the output data in a bandwidth-sharing way, on the basis of which an optimal length ratio of all the FIFOs is achieved, allowing the reading operations to be switched among all the FIFOs without time slot waiting. Therefore, this algorithm enhances the utilization ratio of the reading bandwidth resources so as to obtain higher efficiency than the traditional scheduling algorithms. The reliability and validity of the algorithm are substantiated after its implementation in the field programmable gate array (FPGA) technology, and the bandwidth utilization ratio and the real-time performance of the ultrasonic phased array are enhanced. PMID:29035345
Xie, Bin; Youash, Sabrina
2011-06-14
Providing emergency department (ED) wait time information to the public has been suggested as a mechanism to reduce lengthy ED wait times (by enabling patients to select the ED site with shorter wait time), but the effects of such a program have not been evaluated. We evaluated the effects of such a program in a community with two ED sites. Descriptive statistics for wait times of the two sites before and after the publication of wait time information were used to evaluate the effects of the publication of wait time information on wait times. Multivariate logistical regression was used to test whether or not individual patients used published wait time to decide which site to visit. We found that the rates of wait times exceeding 4 h, and the 95th percentile of wait times in the two sites decreased after the publication of wait time information, even though the average wait times experienced a slight increase. We also found that after controlling for other factors, the site with shorter wait time had a higher likelihood of being selected after the publication of wait time information, but there was no such relationship before the publication. These findings were consistent with the hypothesis that the publication of wait time information leads to patients selecting the site with shorter wait time. While publishing ED wait time information did not improve average wait time, it reduced the rates of lengthy wait times.
Optimal recombination in genetic algorithms for flowshop scheduling problems
NASA Astrophysics Data System (ADS)
Kovalenko, Julia
2016-10-01
The optimal recombination problem consists in finding the best possible offspring as a result of a recombination operator in a genetic algorithm, given two parent solutions. We prove NP-hardness of the optimal recombination for various variants of the flowshop scheduling problem with makespan criterion and criterion of maximum lateness. An algorithm for solving the optimal recombination problem for permutation flowshop problems is built, using enumeration of prefect matchings in a special bipartite graph. The algorithm is adopted for the classical flowshop scheduling problem and for the no-wait flowshop problem. It is shown that the optimal recombination problem for the permutation flowshop scheduling problem is solvable in polynomial time for almost all pairs of parent solutions as the number of jobs tends to infinity.
Performance Analysis of Different Backoff Algorithms for WBAN-Based Emerging Sensor Networks
Khan, Pervez; Ullah, Niamat; Ali, Farman; Ullah, Sana; Hong, Youn-Sik; Lee, Ki-Young; Kim, Hoon
2017-01-01
The Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) procedure of IEEE 802.15.6 Medium Access Control (MAC) protocols for the Wireless Body Area Network (WBAN) use an Alternative Binary Exponential Backoff (ABEB) procedure. The backoff algorithm plays an important role to avoid collision in wireless networks. The Binary Exponential Backoff (BEB) algorithm used in different standards does not obtain the optimum performance due to enormous Contention Window (CW) gaps induced from packet collisions. Therefore, The IEEE 802.15.6 CSMA/CA has developed the ABEB procedure to avoid the large CW gaps upon each collision. However, the ABEB algorithm may lead to a high collision rate (as the CW size is incremented on every alternative collision) and poor utilization of the channel due to the gap between the subsequent CW. To minimize the gap between subsequent CW sizes, we adopted the Prioritized Fibonacci Backoff (PFB) procedure. This procedure leads to a smooth and gradual increase in the CW size, after each collision, which eventually decreases the waiting time, and the contending node can access the channel promptly with little delay; while ABEB leads to irregular and fluctuated CW values, which eventually increase collision and waiting time before a re-transmission attempt. We analytically approach this problem by employing a Markov chain to design the PFB scheme for the CSMA/CA procedure of the IEEE 80.15.6 standard. The performance of the PFB algorithm is compared against the ABEB function of WBAN CSMA/CA. The results show that the PFB procedure adopted for IEEE 802.15.6 CSMA/CA outperforms the ABEB procedure. PMID:28257112
Bjorgan, Asgeir; Randeberg, Lise Lyngsnes
2015-01-01
Processing line-by-line and in real-time can be convenient for some applications of line-scanning hyperspectral imaging technology. Some types of processing, like inverse modeling and spectral analysis, can be sensitive to noise. The MNF (minimum noise fraction) transform provides suitable denoising performance, but requires full image availability for the estimation of image and noise statistics. In this work, a modified algorithm is proposed. Incrementally-updated statistics enables the algorithm to denoise the image line-by-line. The denoising performance has been compared to conventional MNF and found to be equal. With a satisfying denoising performance and real-time implementation, the developed algorithm can denoise line-scanned hyperspectral images in real-time. The elimination of waiting time before denoised data are available is an important step towards real-time visualization of processed hyperspectral data. The source code can be found at http://www.github.com/ntnu-bioopt/mnf. This includes an implementation of conventional MNF denoising. PMID:25654717
Gravelle, Hugh; Siciliani, Luigi
2009-08-01
In many public healthcare systems treatments are rationed by waiting time. We examine the optimal allocation of a fixed supply of a given treatment between different groups of patients. Even in the absence of any distributional aims, welfare is increased by third degree waiting time discrimination: setting different waiting times for different groups waiting for the same treatment. Because waiting time imposes dead weight losses on patients, lower waiting times should be offered to groups with higher marginal waiting time costs and with less elastic demand for the treatment.
Bus-stop Based Real Time Passenger Information System - Case Study Maribor
NASA Astrophysics Data System (ADS)
Čelan, Marko; Klemenčič, Mitja; Mrgole, Anamarija L.; Lep, Marjan
2017-10-01
Real time passenger information system is one of the key element of promoting public transport. For the successful implementation of real time passenger information systems, various components should be considered, such as: passenger needs and requirements, stakeholder involvement, technological solution for tracking, data transfer, etc. This article carrying out designing and evaluation of real time passenger information (RTPI) in the city of Maribor. The design phase included development of methodology for selection of appropriate macro and micro location of the real-time panel, development of a real-time passenger algorithm, definition of a technical specification, financial issues and time frame. The evaluation shows that different people have different requirements; therefore, the system should be adaptable to be used by various types of people, according to the age, the purpose of journey, experience of using public transport, etc. The average difference between perceived waiting time for a bus is 35% higher than the actual waiting time and grow with the headway increase. Experiences from Maribor have shown that the reliability of real time passenger system (from technical point of view) must be close to 100%, otherwise the system may have negative impact on passengers and may discourage the use of public transport. Among considered events of arrivals during the test period, 92% of all prediction were accurate. The cost benefit analysis has focused only on potential benefits from reduced perceived users waiting time and foreseen costs of real time information system in Maribor for 10 years’ period. Analysis shows that the optimal number for implementing real time passenger information system at the bus stops in Maribor is set on 83 bus stops (approx. 20 %) with the highest number of passenger. If we consider all entries at the chosen bus stops, the total perceived waiting time on yearly level could be decreased by about 60,000 hours.
Reducing wait time in a hospital pharmacy to promote customer service.
Slowiak, Julie M; Huitema, Bradley E; Dickinson, Alyce M
2008-01-01
The purpose of this study was to compare the effects of 2 different interventions on wait times at a hospital outpatient pharmacy: (1) giving feedback to employees about customer satisfaction with wait times and (2) giving a combined intervention package that included giving more specific feedback about actual wait times and goal setting for wait time reduction in addition to the customer satisfaction feedback. The relationship between customer satisfaction ratings and wait times was examined to determine whether wait times affected customer service satisfaction. Participants were 10 employees (4 pharmacists and 6 technicians) of an outpatient pharmacy. Wait times and customer satisfaction ratings were collected for "waiting customers." An ABCBA' within-subjects design was used to assess the effects of the interventions on both wait time and customer satisfaction, where A was the baseline (no feedback and no goal setting); B was the customer satisfaction feedback; C was the customer satisfaction feedback, the wait time feedback, and the goal setting for wait time reduction; and A' was a follow-up condition that was similar to the original baseline condition. Wait times were reduced by approximately 20%, and there was concomitant increased shift in levels of customer satisfaction, as indicated by the correlation between these variables (r = -0.57 and P < .05). Given the current prescription-filling process, we do not expect that major, additional reductions in wait times could be produced. Many variables may account for the variability in any individual customer's wait time. Data from this study may provide useful preliminary benchmarking data for standard pharmacy wait times.
Real waiting times for surgery. Proposal for an improved system for their management.
Abásolo, Ignacio; Barber, Patricia; González López-Valcárcel, Beatriz; Jiménez, Octavio
2014-01-01
In Spain, official information on waiting times for surgery is based on the interval between the indication for surgery and its performance. We aimed to estimate total waiting times for surgical procedures, including outpatient visits and diagnostic tests prior to surgery. In addition, we propose an alternative system to manage total waiting times that reduces variability and maximum waiting times without increasing the use of health care resources. This system is illustrated by three surgical procedures: cholecystectomy, carpal tunnel release and inguinal/femoral hernia repair. Using data from two Autonomous Communities, we adjusted, through simulation, a theoretical distribution of the total waiting time assuming independence of the waiting times of each stage of the clinical procedure. We show an alternative system in which the waiting time for the second consultation is established according to the time previously waited for the first consultation. Average total waiting times for cholecystectomy, carpal tunnel release and inguinal/femoral hernia repair were 331, 355 and 137 days, respectively (official data are 83, 68 and 73 days, respectively). Using different negative correlations between waiting times for subsequent consultations would reduce maximum waiting times by between 2% and 15% and substantially reduce heterogeneity among patients, without generating higher resource use. Total waiting times are between two and five times higher than those officially published. The relationship between the waiting times at each stage of the medical procedure may be used to decrease variability and maximum waiting times. Copyright © 2013 SESPAS. Published by Elsevier Espana. All rights reserved.
Time while waiting: patients' experiences of scheduled surgery.
Carr, Tracey; Teucher, Ulrich C; Casson, Alan G
2014-12-01
Research on patients' experiences of wait time for scheduled surgery has centered predominantly on the relative tolerability of perceived wait time and impacts on quality of life. We explored patients' experiences of time while waiting for three types of surgery with varied wait times--hip or knee replacement, shoulder surgery, and cardiac surgery. Thirty-two patients were recruited by their surgeons. We asked participants about their perceptions of time while waiting in two separate interviews. Using interpretative phenomenological analysis (IPA), we discovered connections between participant suffering, meaningfulness of time, and agency over the waiting period and the lived duration of time experience. Our findings reveal that chronological duration is not necessarily the most relevant consideration in determining the quality of waiting experience. Those findings helped us create a conceptual framework for lived wait time. We suggest that clinicians and policy makers consider the complexity of wait time experience to enhance preoperative patient care. © The Author(s) 2014.
Routing of radioactive shipments in networks with time-varying costs and curfews
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bowler, L.A.; Mahmassani, H.S.
This research examines routing of radioactive shipments in highway networks with time-dependent travel times and population densities. A time-dependent least-cost path (TDLCP) algorithm that uses a label-correcting approach is adapted to include curfews and waiting at nodes. A method is developed to estimate time-dependent population densities, which are required to estimate risk associated with the use of a particular highway link at a particular time. The TDLCP algorithm is implemented for example networks and used to examine policy questions related to radioactive shipments. It is observed that when only Interstate highway facilities are used to transport these materials, a shipmentmore » must go through many cities and has difficulty avoiding all of them during their rush hour periods. Decreases in risk, increased departure time flexibility, and modest increases in travel times are observed when primary and/or secondary roads are included in the network. Based on the results of the example implementation, the suitability of the TDLCP algorithm for strategic nuclear material and general radioactive material shipments is demonstrated.« less
NASA Astrophysics Data System (ADS)
Pan, Cong; Zhang, Jie; Qin, Wei
2017-05-01
As a key to improve the performance of the interbay automated material handling system (AMHS) in 300 mm semiconductor wafer fabrication system, the real-time overhead hoist transport (OHT) dispatching problem has received much attention. This problem is first formulated as a special form of assignment problem and it is proved that more than one solution will be obtained by Hungarian algorithm simultaneously. Through proposing and strictly proving two propositions related to the characteristics of these solutions, a modified Hungarian algorithm is designed to distinguish these solutions. Finally, a new real-time OHT dispatching method is carefully designed by implementing the solution obtained by the modified Hungarian algorithm. The experimental results of discrete event simulations show that, compared with conventional Hungarian algorithm dispatching method, the proposed dispatching method that chooses the solution with the maximum variance respectively reduces on average 4 s of the average waiting time and average lead time of wafer lots, and its performance is rather stable in multiple different scenarios of the interbay AMHS with different quantities of shortcuts. This research provides an efficient real-time OHT dispatching mechanism for the interbay AMHS with shortcuts and bypasses.
Leaver, Chad Andrew; Guttmann, Astrid; Zwarenstein, Merrick; Rowe, Brian H; Anderson, Geoff; Stukel, Therese; Golden, Brian; Bell, Robert; Morra, Dante; Abrams, Howard; Schull, Michael J
2009-06-08
Rigorous evaluation of an intervention requires that its allocation be unbiased with respect to confounders; this is especially difficult in complex, system-wide healthcare interventions. We developed a short survey instrument to identify factors for a minimization algorithm for the allocation of a hospital-level intervention to reduce emergency department (ED) waiting times in Ontario, Canada. Potential confounders influencing the intervention's success were identified by literature review, and grouped by healthcare setting specific change stages. An international multi-disciplinary (clinical, administrative, decision maker, management) panel evaluated these factors in a two-stage modified-delphi and nominal group process based on four domains: change readiness, evidence base, face validity, and clarity of definition. An original set of 33 factors were identified from the literature. The panel reduced the list to 12 in the first round survey. In the second survey, experts scored each factor according to the four domains; summary scores and consensus discussion resulted in the final selection and measurement of four hospital-level factors to be used in the minimization algorithm: improved patient flow as a hospital's leadership priority; physicians' receptiveness to organizational change; efficiency of bed management; and physician incentives supporting the change goal. We developed a simple tool designed to gather data from senior hospital administrators on factors likely to affect the success of a hospital patient flow improvement intervention. A minimization algorithm will ensure balanced allocation of the intervention with respect to these factors in study hospitals.
Liu, Jiming; Tao, Li; Xiao, Bo
2011-01-01
Prior research shows that clinical demand and supplier capacity significantly affect the throughput and the wait time within an isolated unit. However, it is doubtful whether characteristics (i.e., demand, capacity, throughput, and wait time) of one unit would affect the wait time of subsequent units on the patient flow process. Focusing on cardiac care, this paper aims to examine the impact of characteristics of the catheterization unit (CU) on the wait time of cardiac surgery unit (SU). This study integrates published data from several sources on characteristics of the CU and SU units in 11 hospitals in Ontario, Canada between 2005 and 2008. It proposes a two-layer wait time model (with each layer representing one unit) to examine the impact of CU's characteristics on the wait time of SU and test the hypotheses using the Partial Least Squares-based Structural Equation Modeling analysis tool. Results show that: (i) wait time of CU has a direct positive impact on wait time of SU (β = 0.330, p < 0.01); (ii) capacity of CU has a direct positive impact on demand of SU (β = 0.644, p < 0.01); (iii) within each unit, there exist significant relationships among different characteristics (except for the effect of throughput on wait time in SU). Characteristics of CU have direct and indirect impacts on wait time of SU. Specifically, demand and wait time of preceding unit are good predictors for wait time of subsequent units. This suggests that considering such cross-unit effects is necessary when alleviating wait time in a health care system. Further, different patient risk profiles may affect wait time in different ways (e.g., positive or negative effects) within SU. This implies that the wait time management should carefully consider the relationship between priority triage and risk stratification, especially for cardiac surgery.
Schachter, Michael E; Romann, Alexandra; Djurdev, Ognjenka; Levin, Adeera; Beaulieu, Monica
2013-08-29
Early referral and management of high-risk chronic kidney disease may prevent or delay the need for dialysis. Automatic eGFR reporting has increased demand for out-patient nephrology consultations and in some cases, prolonged queues. In Canada, a national task force suggested the development of waiting time targets, which has not been done for nephrology. We sought to describe waiting time for outpatient nephrology consultations in British Columbia (BC). Data collection occurred in 2 phases: 1) Baseline Description (Jan 18-28, 2010) and 2) Post Waiting Time Benchmark-Introduction (Jan 16-27, 2012). Waiting time was defined as the interval from receipt of referral letters to assessment. Using a modified Delphi process, Nephrologists and Family Physicians (FP) developed waiting time targets for commonly referred conditions through meetings and surveys. Rules were developed to weigh-in nephrologists', FPs', and patients' perspectives in order to generate waiting time benchmarks. Targets consider comorbidities, eGFR, BP and albuminuria. Referred conditions were assigned a priority score between 1-4. BC nephrologists were encouraged to centrally triage referrals to see the first available nephrologist. Waiting time benchmarks were simultaneously introduced to guide patient scheduling. A post-intervention waiting time evaluation was then repeated. In 2010 and 2012, 43/52 (83%) and 46/57 (81%) of BC nephrologists participated. Waiting time decreased from 98(IQR44,157) to 64(IQR21,120) days from 2010 to 2012 (p = <.001), despite no change in referral eGFR, demographics, nor number of office hrs/wk. Waiting time improved most for high priority patients. An integrated, Provincial initiative to measure wait times, develop waiting benchmarks, and engage physicians in active waiting time management associated with improved access to nephrologists in BC. Improvements in waiting time was most marked for the highest priority patients, which suggests that benchmarks had an influence on triaging behavior. Further research is needed to determine whether this effect is sustainable.
Bryan, Christopher F; Nelson, Paul W; Shield, Charles F; Ross, Gilbert; Warady, Bradley; Murillo, Daniel; Winklhofer, Franz T
2004-01-01
Transplant centers in the Midwest Transplant Network began transplanting kidneys from A2 or A2B donors into blood group B and O patients in 1986. Since 1991, an OPTN/UNOS variance has permitted us to allocate these kidneys preferentially into B and O waiting list patients. With more than 10 years of experience we have noted the following: 1. Thirty-one percent more blood group B patients were transplanted by allocating them A2 or A2B kidneys from our deceased donors. 2. Ten-year graft survival for B recipients of an A2 or A2B kidney (72%) was equivalent to that for B recipients of a B kidney (69%). 3. Type B recipients of simultaneous pancreas-kidney transplants (n=4) also did well with A2 or A2B organs. 4. Non-A recipients were transplanted only when their anti-A IgG titer history was consistently low (< or =4). 5. Most (90%) blood group B patients had a low anti-A IgG titer history; whereas, only one-third of blood group O patients had a low titer history. 6. Neither ethnicity nor HLA class I sensitization level influenced the anti-A IgG titer history. 7. In an OPO with mostly (87%) white donors, nearly 20% of blood group A donors were A2. 8. Waiting time until transplantation was lower for B patients who received an A2 or A2B kidney than for those who received a B or O kidney. 9. Our OPO blood group B waiting list was reduced from 25 low PRA (<40%) B candidates in 1994 to 4 in July, 2004. 10. Blood group A candidates received 6.4% fewer transplants with our A2/A2B--> B allocation algorithm. 11. Minority patients were transplanted at the same rate when using the A2/A2B--> B allocation algorithm as when using the standard UNOS algorithm for allocating B and O kidneys--> B patients.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 1 2010-10-01 2010-10-01 false Waiting time. 9.10 Section 9.10 Shipping COAST GUARD... § 9.10 Waiting time. The same construction should be given the act when charging for waiting time as... for duty the waiting time amounts to at least one hour. ...
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 1 2012-10-01 2012-10-01 false Waiting time. 9.10 Section 9.10 Shipping COAST GUARD... § 9.10 Waiting time. The same construction should be given the act when charging for waiting time as... for duty the waiting time amounts to at least one hour. ...
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 1 2011-10-01 2011-10-01 false Waiting time. 9.10 Section 9.10 Shipping COAST GUARD... § 9.10 Waiting time. The same construction should be given the act when charging for waiting time as... for duty the waiting time amounts to at least one hour. ...
Wijeysundera, Harindra C; Wong, William W L; Bennell, Maria C; Fremes, Stephen E; Radhakrishnan, Sam; Peterson, Mark; Ko, Dennis T
2014-10-01
There is increasing demand for transcatheter aortic valve replacement (TAVR) as the primary treatment option for patients with severe aortic stenosis who are high-risk surgical candidates or inoperable. We used mathematical simulation models to estimate the hypothetical effectiveness of TAVR with increasing wait times. We applied discrete event modelling, using data from the Placement of Aortic Transcatheter Valves (PARTNER) trials. We compared TAVR with medical therapy in the inoperable cohort, and compared TAVR to conventional aortic valve surgery in the high-risk cohort. One-year mortality and wait-time deaths were calculated in different scenarios by varying TAVR wait times from 10 days to 180 days, while maintaining a constant wait time for surgery at a mean of 15.6 days. In the inoperable cohort, the 1-year mortality for medical therapy was 50%. When the TAVR wait time was 10 days, the TAVR wait-time mortality was 1.9% with a 1-year mortality of 31.5%. TAVR wait-time deaths increased to 28.9% with a 180-day wait, with a 1-year mortality of 41.4%. In the high-risk cohort, the wait-time deaths and 1-year mortality for the surgical patients were 2.5% and 27%, respectively. The TAVR wait-time deaths increased from 2.2% with a 10-day wait to 22.4% with a 180-day wait, and a corresponding increase in 1-year mortality from 24.5% to 32.6%. Mortality with TAVR exceeded surgery when TAVR wait times exceeded 60 days. Modest increases in TAVR wait times have a substantial effect on the effectiveness of TAVR in inoperable patients and high-risk surgical candidates. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
Two Effective Ways to Implement Wait Time. A Symposium on Wait Time.
ERIC Educational Resources Information Center
Swift, J. Nathan; And Others
The effects of instructional guides and a wait time feedback device (called a "Wait Timer") on the classroom interaction of middle school science teachers are examined. The Wait Timer, an unobtrusive indicator of wait time, is an automatic device that activates a light when a person speaks. The duration of the light at the end of a…
Wait Time for Counseling Affecting Perceived Stigma and Attitude toward the University
ERIC Educational Resources Information Center
Blau, Gary; DiMino, John; Sheridan, Natalie; Stein, Alexander; Casper, Steven; Chessler, Marcy; Beverly, Clyde
2015-01-01
A sample of 99 undergraduates in counseling was divided into two groups based on wait time from triage to intake, "less wait time" (up to two weeks) versus "more wait time" (at least two weeks). The less wait time group showed "higher willingness to recommend the university," "higher institutional…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elmagarmid, A.K.
The availability of distributed data bases is directly affected by the timely detection and resolution of deadlocks. Consequently, mechanisms are needed to make deadlock detection algorithms resilient to failures. Presented first is a centralized algorithm that allows transactions to have multiple requests outstanding. Next, a new distributed deadlock detection algorithm (DDDA) is presented, using a global detector (GD) to detect global deadlocks and local detectors (LDs) to detect local deadlocks. This algorithm essentially identifies transaction-resource interactions that m cause global (multisite) deadlocks. Third, a deadlock detection algorithm utilizing a transaction-wait-for (TWF) graph is presented. It is a fully disjoint algorithmmore » that allows multiple outstanding requests. The proposed algorithm can achieve improved overall performance by using multiple disjoint controllers coupled with the two-phase property while maintaining the simplicity of centralized schemes. Fourth, an algorithm that combines deadlock detection and avoidance is given. This algorithm uses concurrent transaction controllers and resource coordinators to achieve maximum distribution. The language of CSP is used to describe this algorithm. Finally, two efficient deadlock resolution protocols are given along with some guidelines to be used in choosing a transaction for abortion.« less
Reducing pharmacy wait time to promote customer service: a follow-up study.
Slowiak, Julie M; Huitema, Bradley E
2015-01-01
The present study had 3 objectives: (1) to evaluate the effects of 2 different interventions (feedback regarding customer satisfaction with wait time and combined feedback and goal setting) on wait time in a hospital outpatient pharmacy; (2) to assess the extent to which the previously applied interventions maintained their effects; and (3) to evaluate the differences between the effects of the original study and those of the present follow-up study. Participants were 10 employees (4 pharmacists and 6 technicians) of an outpatient pharmacy. Wait times and customer satisfaction ratings were collected for "waiting customers." An ABCB within-subjects design was used to assess the effects of the interventions on both wait time and customer satisfaction, where A was the baseline (no feedback and no goal setting); B was the customer satisfaction feedback; and C was the customer satisfaction feedback, the wait time feedback, and the goal setting for wait time reduction. Wait time decreased after baseline when the combined intervention was introduced, and wait time increased with the reintroduction of satisfaction feedback (alone). The results of the replication study confirm the pattern of the results of the original study and demonstrate high sensitivity of levels of customer satisfaction with wait time. The most impressive result of the replication is the nearly 2-year maintenance of lower wait time between the end of the original study and the beginning (baseline) of the replication.
Patterson, Brendan M; Eskildsen, Scott M; Clement, R Carter; Lin, Feng-Chang; Olcott, Christopher W; Del Gaizo, Daniel J; Tennant, Joshua N
2017-01-01
Clinic wait time is considered an important predictor of patient satisfaction. The goal of this study was to determine whether patient satisfaction among orthopedic patients is associated with clinic wait time and time with the provider. The authors prospectively enrolled 182 patients at their outpatient orthopedic clinic. Clinic wait time was defined as the time between patient check-in and being seen by the surgeon. Time spent with the provider was defined as the total time the patient spent in the examination room with the surgeon. The Consumer Assessment of Healthcare Providers and Systems survey was used to measure patient satisfaction. Factors associated with increased patient satisfaction included patient age and increased time with the surgeon (P=.024 and P=.037, respectively), but not clinic wait time (P=.625). Perceived wait time was subject to a high level of error, and most patients did not accurately report whether they had been waiting longer than 15 minutes to see a provider until they had waited at least 60 minutes (P=.007). If the results of the current study are generalizable, time with the surgeon is associated with patient satisfaction in orthopedic clinics, but wait time is not. Further, the study findings showed that patients in this setting did not have an accurate perception of actual wait time, with many patients underestimating the time they waited to see a provider. Thus, a potential strategy for improving patient satisfaction is to spend more time with each patient, even at the expense of increased wait time. [Orthopedics. 2017; 40(1):43-48.]. Copyright 2016, SLACK Incorporated.
Rotational dynamics in supercooled water from nuclear spin relaxation and molecular simulations.
Qvist, Johan; Mattea, Carlos; Sunde, Erik P; Halle, Bertil
2012-05-28
Structural dynamics in liquid water slow down dramatically in the supercooled regime. To shed further light on the origin of this super-Arrhenius temperature dependence, we report high-precision (17)O and (2)H NMR relaxation data for H(2)O and D(2)O, respectively, down to 37 K below the equilibrium freezing point. With the aid of molecular dynamics (MD) simulations, we provide a detailed analysis of the rotational motions probed by the NMR experiments. The NMR-derived rotational correlation time τ(R) is the integral of a time correlation function (TCF) that, after a subpicosecond librational decay, can be described as a sum of two exponentials. Using a coarse-graining algorithm to map the MD trajectory on a continuous-time random walk (CTRW) in angular space, we show that the slowest TCF component can be attributed to large-angle molecular jumps. The mean jump angle is ∼48° at all temperatures and the waiting time distribution is non-exponential, implying dynamical heterogeneity. We have previously used an analogous CTRW model to analyze quasielastic neutron scattering data from supercooled water. Although the translational and rotational waiting times are of similar magnitude, most translational jumps are not synchronized with a rotational jump of the same molecule. The rotational waiting time has a stronger temperature dependence than the translation one, consistent with the strong increase of the experimentally derived product τ(R) D(T) at low temperatures. The present CTRW jump model is related to, but differs in essential ways from the extended jump model proposed by Laage and co-workers. Our analysis traces the super-Arrhenius temperature dependence of τ(R) to the rotational waiting time. We present arguments against interpreting this temperature dependence in terms of mode-coupling theory or in terms of mixture models of water structure.
Wait Time and Effective Social Studies Instruction: What Can Research in Science Education Tell Us?
ERIC Educational Resources Information Center
Atwood, Virgina A.; Wilen, William W.
1991-01-01
Defines wait time as the length of time teachers wait for answers from students after asking a question. Maintains that increasing wait time can stimulate reflective thinking and student involvement. Reviews the research literature on wait time studies in science education. Finds that student responses improve and participation expands with…
Optimization model of conventional missile maneuvering route based on improved Floyd algorithm
NASA Astrophysics Data System (ADS)
Wu, Runping; Liu, Weidong
2018-04-01
Missile combat plays a crucial role in the victory of war under high-tech conditions. According to the characteristics of maneuver tasks of conventional missile units in combat operations, the factors influencing road maneuvering are analyzed. Based on road distance, road conflicts, launching device speed, position requirements, launch device deployment, Concealment and so on. The shortest time optimization model was built to discuss the situation of road conflict and the strategy of conflict resolution. The results suggest that in the process of solving road conflict, the effect of node waiting is better than detour to another way. In this study, we analyzed the deficiency of the traditional Floyd algorithm which may limit the optimal way of solving road conflict, and put forward the improved Floyd algorithm, meanwhile, we designed the algorithm flow which would be better than traditional Floyd algorithm. Finally, throgh a numerical example, the model and the algorithm were proved to be reliable and effective.
2013-01-01
Background Early referral and management of high-risk chronic kidney disease may prevent or delay the need for dialysis. Automatic eGFR reporting has increased demand for out-patient nephrology consultations and in some cases, prolonged queues. In Canada, a national task force suggested the development of waiting time targets, which has not been done for nephrology. Methods We sought to describe waiting time for outpatient nephrology consultations in British Columbia (BC). Data collection occurred in 2 phases: 1) Baseline Description (Jan 18-28, 2010) and 2) Post Waiting Time Benchmark-Introduction (Jan 16-27, 2012). Waiting time was defined as the interval from receipt of referral letters to assessment. Using a modified Delphi process, Nephrologists and Family Physicians (FP) developed waiting time targets for commonly referred conditions through meetings and surveys. Rules were developed to weigh-in nephrologists’, FPs’, and patients’ perspectives in order to generate waiting time benchmarks. Targets consider comorbidities, eGFR, BP and albuminuria. Referred conditions were assigned a priority score between 1-4. BC nephrologists were encouraged to centrally triage referrals to see the first available nephrologist. Waiting time benchmarks were simultaneously introduced to guide patient scheduling. A post-intervention waiting time evaluation was then repeated. Results In 2010 and 2012, 43/52 (83%) and 46/57 (81%) of BC nephrologists participated. Waiting time decreased from 98(IQR44,157) to 64(IQR21,120) days from 2010 to 2012 (p = <.001), despite no change in referral eGFR, demographics, nor number of office hrs/wk. Waiting time improved most for high priority patients. Conclusions An integrated, Provincial initiative to measure wait times, develop waiting benchmarks, and engage physicians in active waiting time management associated with improved access to nephrologists in BC. Improvements in waiting time was most marked for the highest priority patients, which suggests that benchmarks had an influence on triaging behavior. Further research is needed to determine whether this effect is sustainable. PMID:23988113
NASA Astrophysics Data System (ADS)
Zakharchenko, V. D.; Kovalenko, I. G.
2014-05-01
A new method for the line-of-sight velocity estimation of a high-speed near-Earth object (asteroid, meteorite) is suggested. The method is based on the use of fractional, one-half order derivative of a Doppler signal. The algorithm suggested is much simpler and more economical than the classical one, and it appears preferable for use in orbital weapon systems of threat response. Application of fractional differentiation to quick evaluation of mean frequency location of the reflected Doppler signal is justified. The method allows an assessment of the mean frequency in the time domain without spectral analysis. An algorithm structure for the real-time estimation is presented. The velocity resolution estimates are made for typical asteroids in the X-band. It is shown that the wait time can be shortened by orders of magnitude compared with similar value in the case of a standard spectral processing.
Dynamic Bus Travel Time Prediction Models on Road with Multiple Bus Routes
Bai, Cong; Peng, Zhong-Ren; Lu, Qing-Chang; Sun, Jian
2015-01-01
Accurate and real-time travel time information for buses can help passengers better plan their trips and minimize waiting times. A dynamic travel time prediction model for buses addressing the cases on road with multiple bus routes is proposed in this paper, based on support vector machines (SVMs) and Kalman filtering-based algorithm. In the proposed model, the well-trained SVM model predicts the baseline bus travel times from the historical bus trip data; the Kalman filtering-based dynamic algorithm can adjust bus travel times with the latest bus operation information and the estimated baseline travel times. The performance of the proposed dynamic model is validated with the real-world data on road with multiple bus routes in Shenzhen, China. The results show that the proposed dynamic model is feasible and applicable for bus travel time prediction and has the best prediction performance among all the five models proposed in the study in terms of prediction accuracy on road with multiple bus routes. PMID:26294903
Dynamic Bus Travel Time Prediction Models on Road with Multiple Bus Routes.
Bai, Cong; Peng, Zhong-Ren; Lu, Qing-Chang; Sun, Jian
2015-01-01
Accurate and real-time travel time information for buses can help passengers better plan their trips and minimize waiting times. A dynamic travel time prediction model for buses addressing the cases on road with multiple bus routes is proposed in this paper, based on support vector machines (SVMs) and Kalman filtering-based algorithm. In the proposed model, the well-trained SVM model predicts the baseline bus travel times from the historical bus trip data; the Kalman filtering-based dynamic algorithm can adjust bus travel times with the latest bus operation information and the estimated baseline travel times. The performance of the proposed dynamic model is validated with the real-world data on road with multiple bus routes in Shenzhen, China. The results show that the proposed dynamic model is feasible and applicable for bus travel time prediction and has the best prediction performance among all the five models proposed in the study in terms of prediction accuracy on road with multiple bus routes.
[Dealing with Waiting Times in Health Systems - An International Comparative Overview].
Finkenstädt, V
2015-10-01
Waiting times in the health system are a form of rationing that exists in many countries. Previous studies on this topic are mainly related to the problem of international comparability of waiting times or on the presentation of national strategies as to how they should be reduced. This review adds to this analysis and examines how the OECD countries deal with waiting times in the health-care system and investigates which information is published about waiting for what purpose. Furthermore, waiting times and the type of health system financing are compared. A systematic internet research on waiting times in the health-care system was conducted on the websites of the competent authorities (Ministry of Health or other authorities and institutions). The identified publications were then examined for the purpose of their deployment. Finally, the OECD Health Data were analysed to determine the relationship between tax and contribution financing of public health care expenditure. The primary form of financing was compared with the results of the waiting time analysis. 16 OECD countries are identified which officially collect and publish administrative data on waiting times on the Internet. The data are processed differently depending on the country. By providing this information, two main objectives are pursued: a public monitoring of waiting times in the health system (14 countries) and information for patients on waiting times (9 countries). Official statistics on waiting times exist mainly in countries with tax-financed health systems, whereas this is not the case in the majority of OECD countries with health systems that are funded through contributions. The publication of administrative waiting times data is primarily intended to inform the patient and as a performance indicator in terms of access to health care. Even if data on waiting times are published, the publication of indicators and the management of waiting lists alone will not solve the problem. Rather, the analysis shows that in tax-funded health systems access to medical care is frequently rationed and the demand side is often regulated by waiting lists. © Georg Thieme Verlag KG Stuttgart · New York.
Outpatient Office Wait Times and Quality of Care for Medicaid Patients
Oostrom, Tamar; Einav, Liran; Finkelstein, Amy
2018-01-01
Time spent in the doctor’s waiting room captures an important aspect of the healthcare experience. We analyzed data on 21 million outpatient visits obtained from electronic health record systems, allowing us to measure time spent in the waiting room beyond the scheduled appointment time. Median wait time was just over 4 minutes. Almost one-fifth of visits had waits longer than 20 minutes, and 10% were over 30 minutes. Waits were shorter for early morning appointments, younger patients, and at larger practices. Median wait time was 4.1 minutes for privately-insured and 4.6 minutes for Medicaid patients; adjusting for patient and appointment characteristics, Medicaid patients were 20% more likely than the privately-insured to wait longer than 20 minutes (P<0.001), with most of this disparity explained by differences in practices and providers they saw. Wait time for Medicaid patients relative to the privately-insured was longer in states with relatively lower Medicaid reimbursement rates. PMID:28461348
Ray, Shreyasi; Kirtania, Jyotirmay
2017-01-01
Abundant published literature exists addressing the issues of outpatient waiting lists before surgery. However, there is no published literature on inpatient waiting time before elective surgical procedures. This study aims to measure the inpatient waiting time, identify the factors that affect the inpatient waiting time, and recommend the ways of reducing the waiting time of inpatients before elective surgical procedures, at a state government teaching hospital in India. Descriptive research methods and quality control tools were used for this prospective observational study. Descriptive statistics, Shapiro-Wilk test of normality, Wilcoxon-Mann-Whitney Test, and Kruskal-Wallis test were used. Pareto charts were used to highlight the most important modifiable factors among the set of factors causing increased waiting time. We also applied the M/M/c model (Erlang - A model) of queue theory to analyze the traffic intensity and system congestion. The median waiting time of inpatients before elective surgery was 12 days (interquartile range = 11.5 days). The waiting time was influenced significantly (P < 0.05) by the patient's age, physical status, and the financial status. The surgical specialty, blood product booking and procurement, cross-specialty consultation before surgery, and Intensive Care Unit booking were the other important factors. Modifiable and nonmodifiable factors affecting the inpatient waiting time of surgical patients were identified. Control measures that can reduce the waiting time of inpatients before elective surgery were identified.
The surgical waiting time initiative: A review of the Nigerian situation
Abdulkareem, Imran Haruna
2014-01-01
SUMMARY The concept of surgical waiting time initiative (SWAT) was introduced in developed countries to reduce elective surgery waiting lists and increase efficiency of care. It was supplemented by increasing popularity of day surgery, which shortens elective waiting lists and minimises cancellations. It is established in Western countries, but not in developing countries like Nigeria where it is still evolving. A search was carried out in Pub Med, Google, African journals online (AJOL), Athens and Ovid for relevant publications on elective surgery waiting list in Nigeria, published in English language. Words include waiting/wait time, waiting time initiative, time to surgery, waiting for operations, waiting for intervention, waiting for procedures and time before surgery in Nigeria. A total of 37 articles published from Nigeria in relation to various waiting times were found from the search and fulfilled the inclusion criteria. Among them, 11 publications (29.7%) were related to emergency surgery waiting times, 10 (27%) were related to clinic waiting times, 9 (24.3%) were related to day case surgery, 2 (5.5%) were related to investigation waiting times and only 5 (13.5%) articles were specifically published on elective surgery waiting times. A total of 9 articles (24.5%) were published from obstetrics and gynaecology (OG), 7 (19%) from general surgery, 5 (13.5%) from public health, 3 (8%) from orthopaedics, 3 (8%) from general practice (GP), 3 (8%) from paediatrics/paediatric surgery, 2 (5.5%) from ophthalmology, 1 (2.7%) from ear, nose and throat (ENT), 1 (2.7%) from plastic surgery, 1 (2.7%) from urology and only 1 (2.7%) article was published from dental/maxillofacial surgery. Waiting times mean different things to different health practitioners in Nigeria. There were only 5/37 articles (13.5%) specifically related to elective surgery waiting times in Nigerian hospitals, which show that the concept of the SWAT is still evolving in Nigeria. Of the 37, 11 (24.5%) publications were from obstetrics and gynaecology (O & G) alone, but these were mostly related to emergency antenatal care rather than surgery. Therefore, more research and initiative needs to be undertaken from all the surgical sub-specialties in order to disseminate this concept of SWAT towards early diagnosis and treatment of elective life-threatening conditions, as well as effective patient care. Adopting this concept will help healthcare managers and policy makers to stream line and ring face resources to cater for non-urgent or semi-urgent cases presenting to our hospitals in Nigeria. PMID:25538359
The surgical waiting time initiative: A review of the Nigerian situation.
Abdulkareem, Imran Haruna
2014-11-01
The concept of surgical waiting time initiative (SWAT) was introduced in developed countries to reduce elective surgery waiting lists and increase efficiency of care. It was supplemented by increasing popularity of day surgery, which shortens elective waiting lists and minimises cancellations. It is established in Western countries, but not in developing countries like Nigeria where it is still evolving. A search was carried out in Pub Med, Google, African journals online (AJOL), Athens and Ovid for relevant publications on elective surgery waiting list in Nigeria, published in English language. Words include waiting/wait time, waiting time initiative, time to surgery, waiting for operations, waiting for intervention, waiting for procedures and time before surgery in Nigeria. A total of 37 articles published from Nigeria in relation to various waiting times were found from the search and fulfilled the inclusion criteria. Among them, 11 publications (29.7%) were related to emergency surgery waiting times, 10 (27%) were related to clinic waiting times, 9 (24.3%) were related to day case surgery, 2 (5.5%) were related to investigation waiting times and only 5 (13.5%) articles were specifically published on elective surgery waiting times. A total of 9 articles (24.5%) were published from obstetrics and gynaecology (OG), 7 (19%) from general surgery, 5 (13.5%) from public health, 3 (8%) from orthopaedics, 3 (8%) from general practice (GP), 3 (8%) from paediatrics/paediatric surgery, 2 (5.5%) from ophthalmology, 1 (2.7%) from ear, nose and throat (ENT), 1 (2.7%) from plastic surgery, 1 (2.7%) from urology and only 1 (2.7%) article was published from dental/maxillofacial surgery. Waiting times mean different things to different health practitioners in Nigeria. There were only 5/37 articles (13.5%) specifically related to elective surgery waiting times in Nigerian hospitals, which show that the concept of the SWAT is still evolving in Nigeria. Of the 37, 11 (24.5%) publications were from obstetrics and gynaecology (O & G) alone, but these were mostly related to emergency antenatal care rather than surgery. Therefore, more research and initiative needs to be undertaken from all the surgical sub-specialties in order to disseminate this concept of SWAT towards early diagnosis and treatment of elective life-threatening conditions, as well as effective patient care. Adopting this concept will help healthcare managers and policy makers to stream line and ring face resources to cater for non-urgent or semi-urgent cases presenting to our hospitals in Nigeria.
Should I stay or should I go? Hospital emergency department waiting times and demand.
Sivey, Peter
2018-03-01
In the absence of the price mechanism, hospital emergency departments rely on waiting times, alongside prioritisation mechanisms, to restrain demand and clear the market. This paper estimates by how much the number of treatments demanded is reduced by a higher waiting time. I use variation in waiting times for low-urgency patients caused by rare and resource-intensive high-urgency patients to estimate the relationship. I find that when waiting times are higher, more low-urgency patients are deterred from treatment and leave the hospital during the waiting period without being treated. The waiting time elasticity of demand for low-urgency patients is approximately -0.25 and is highest for the lowest-urgency patients. Copyright © 2017 John Wiley & Sons, Ltd.
Kielar, Ania Z; El-Maraghi, Robert H; Schweitzer, Mark E
2010-08-01
In Canada, equal access to health care is the goal, but this is associated with wait times. Wait times should be fair rather than uniform, taking into account the urgency of the problem as well as the time an individual has already waited. In November 2004, the Ontario government began addressing this issue. One of the first steps was to institute benchmarks reflecting "acceptable" wait times for CT and MRI. A public Web site was developed indicating wait times at each Local Health Integration Network. Since starting the Wait Time Information Program, there has been a sustained reduction in wait times for Ontarians requiring CT and MRI. The average wait time for a CT scan went from 81 days in September 2005 to 47 days in September 2009. For MRI, the resulting wait time was reduced from 120 to 105 days. Increased patient scans have been achieved by purchasing new CT and MRI scanners, expanding hours of operation, and improving patient throughput using strategies learned from the Lean initiative, based on Toyota's manufacturing philosophy for car production. Institution-specific changes in booking procedures have been implemented. Concurrently, government guidelines have been developed to ensure accountability for monies received. The Ontario Wait Time Information Program is an innovative first step in improving fair and equitable access to publicly funded imaging services. There have been reductions in wait times for both CT and MRI. As various new processes are implemented, further review will be necessary for each step to determine their individual efficacy. Copyright 2010 American College of Radiology. Published by Elsevier Inc. All rights reserved.
[Influence of waiting time on patient and companion satisfaction].
Fontova-Almató, A; Juvinyà-Canal, D; Suñer-Soler, R
2015-01-01
To evaluate patient and companion satisfaction of a hospital Emergency Department and its relationship with waiting time. Prospective, observational study. Hospital de Figueres Emergency Department (Girona, Spain). sociodemographic characteristics, satisfaction level, real and perceived waiting time for triage and being seen by a physician. A total of 285 responses were received from patients and companions. The mean age of the patients and companions (n=257) was 54.6years (SD=18.3). The mean overall satisfaction (n=273) was 7.6 (SD=2.2). Lower perceived waiting time until nurse triage was related to higher overall satisfaction (Spearman rho (ρ)=-0.242, P<.001), and lower perceived waiting time until being seen by physician, with a higher overall satisfaction (ρ=-0.304; P<.001). Users who were informed about estimated waiting time showed higher satisfaction than those who were not informed (P=.001). Perceived waiting time and the information about estimated waiting time determined overall satisfaction. Copyright © 2014 SECA. Published by Elsevier Espana. All rights reserved.
Evaluating the primary-to-specialist referral system for elective hip and knee arthroplasty.
Fyie, Ken; Frank, Cy; Noseworthy, Tom; Christiansen, Tanya; Marshall, Deborah A
2014-02-01
Persistently long waiting times for hip and knee total joint arthroplasty (TJA) specialist consultations have been identified as a problem. This study described referral processes and practices, and their impact on the waiting time from referral to consultation for TJA. A mixed-methods retrospective study incorporating semi-structured interviews, patient chart reviews and observational studies was conducted at three clinic sites in Alberta, Canada. A total of 218 charts were selected for analysis. Standardized definitions were applied to key event dates. Performance measures included waiting times percentage of referrals initially accepted. Voluntary (patient-related) and involuntary (health system-related) waiting times were quantified. All three clinics had defined, but differing, referral processing rules. The mean time from referral to consultation ranged from 51 to 139 business days. Choosing a specific surgeon for consultation rather than a next available surgeon lengthened waits by 10-47 business days. Involuntary waiting times accounted for at least 11% of total waiting time. Approximately 40-80% of the time patients with TJA wait for surgery was in the consultation period. Fifty-four per cent of new referrals were initially rejected, prolonging patient waits by 8-46 business days. Our results suggest that variation in referral processing led to increased waiting times for patients. The large proportion of total wait attributable to waiting for a surgical consultation makes failure to measure and evaluate this period a significant omission. Improving referral processes and decreasing variation between clinics would improve patient access to these specialist referrals in Alberta. © 2013 John Wiley & Sons, Ltd.
International comparisons of waiting times in health care--limitations and prospects.
Viberg, Nina; Forsberg, Birger C; Borowitz, Michael; Molin, Roger
2013-09-01
Long waiting times for health care is an important health policy issue in many countries, and many have introduced some form of national waiting time guarantees. International comparison of waiting times are critical for countries to improve policy and for patients to be able to make informed choices, especially in Europe, where patients have the right to seek care in other countries if there is undue delay. The objective of this study was to describe how countries measure waiting times and to assess whether waiting times can be compared internationally. Twenty-three OECD countries were included. Information was collected through scientific articles, official and unofficial documents and web pages. Fifteen of the 23 countries monitor and publish national waiting time statistics and have some form of waiting time guarantees. There are significant differences in how waiting times are measured: whether they measure the "ongoing" or "completed" waiting period what kind of care the patient is waiting for; the parameters used; and where in the patient journey the measurement begins. Current national waiting time statistics are of limited use for comparing health care availability among the various countries due to the differences in measurements and data collection. Different methodological issues must be taken into account when making such cross-country comparisons. Within the given context of national sovereignty of health systems it would be desirable if countries could collaborate in order to facilitate international comparisons. Such comparisons would be of benefit to all involved in the process of continuous improvement of health services. They would also benefit patients who seek cross-border alternatives for their care. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.
Fault-tolerant wait-free shared objects
NASA Technical Reports Server (NTRS)
Jayanti, Prasad; Chandra, Tushar D.; Toueg, Sam
1992-01-01
A concurrent system consists of processes communicating via shared objects, such as shared variables, queues, etc. The concept of wait-freedom was introduced to cope with process failures: each process that accesses a wait-free object is guaranteed to get a response even if all the other processes crash. However, if a wait-free object 'crashes,' all the processes that access that object are prevented from making progress. In this paper, we introduce the concept of fault-tolerant wait-free objects, and study the problem of implementing them. We give a universal method to construct fault-tolerant wait-free objects, for all types of 'responsive' failures (including one in which faulty objects may 'lie'). In sharp contrast, we prove that many common and interesting types (such as queues, sets, and test&set) have no fault-tolerant wait-free implementations even under the most benign of the 'non-responsive' types of failure. We also introduce several concepts and techniques that are central to the design of fault-tolerant concurrent systems: the concepts of self-implementation and graceful degradation, and techniques to automatically increase the fault-tolerance of implementations. We prove matching lower bounds on the resource complexity of most of our algorithms.
Can We Predict Patient Wait Time?
Pianykh, Oleg S; Rosenthal, Daniel I
2015-10-01
The importance of patient wait-time management and predictability can hardly be overestimated: For most hospitals, it is the patient queues that drive and define every bit of clinical workflow. The objective of this work was to study the predictability of patient wait time and identify its most influential predictors. To solve this problem, we developed a comprehensive list of 25 wait-related parameters, suggested in earlier work and observed in our own experiments. All parameters were chosen as derivable from a typical Hospital Information System dataset. The parameters were fed into several time-predicting models, and the best parameter subsets, discovered through exhaustive model search, were applied to a large sample of actual patient wait data. We were able to discover the most efficient wait-time prediction factors and models, such as the line-size models introduced in this work. Moreover, these models proved to be equally accurate and computationally efficient. Finally, the selected models were implemented in our patient waiting areas, displaying predicted wait times on the monitors located at the front desks. The limitations of these models are also discussed. Optimal regression models based on wait-line sizes can provide accurate and efficient predictions for patient wait time. Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.
The effect of waiting times on demand and supply for elective surgery: Evidence from Italy.
Riganti, Andrea; Siciliani, Luigi; Fiorio, Carlo V
2017-09-01
Waiting times are a major policy concern in publicly funded health systems across OECD countries. Economists have argued that, in the presence of excess demand, waiting times act as nonmonetary prices to bring demand for and supply of health care in equilibrium. Using administrative data disaggregated by region and surgical procedure over 2010-2014 in Italy, we estimate demand and supply elasticities with respect to waiting times. We employ linear regression models with first differences and instrumental variables to deal with endogeneity of waiting times. We find that demand is inelastic to waiting times while supply is more elastic. Estimates of demand elasticity are between -0.15 to -0.24. Our results have implications on the effectiveness of policies aimed at increasing supply and their ability to reduce waiting times. Copyright © 2017 John Wiley & Sons, Ltd.
Electron Waiting Times of a Cooper Pair Splitter
NASA Astrophysics Data System (ADS)
Walldorf, Nicklas; Padurariu, Ciprian; Jauho, Antti-Pekka; Flindt, Christian
2018-02-01
Electron waiting times are an important concept in the analysis of quantum transport in nanoscale conductors. Here we show that the statistics of electron waiting times can be used to characterize Cooper pair splitters that create spatially separated spin-entangled electrons. A short waiting time between electrons tunneling into different leads is associated with the fast emission of a split Cooper pair, while long waiting times are governed by the slow injection of Cooper pairs from a superconductor. Experimentally, the waiting time distributions can be measured using real-time single-electron detectors in the regime of slow tunneling, where conventional current measurements are demanding. Our work is important for understanding the fundamental transport processes in Cooper pair splitters and the predictions may be verified using current technology.
Waiting time effect of a GM type orifice pulse tube refrigerator
NASA Astrophysics Data System (ADS)
Zhu, Shaowei; Kakimi, Yasuhiro; Matsubara, Yoichi
In a general GM type orifice pulse tube refrigerator, there are two short periods during which both the high pressure valve and the low pressure valve are closed in one cycle. We call the short period `waiting time'. The pressure differences across the high pressure valve and the low pressure valve are decreased by using long waiting time. The pressure difference loss is decreased. Thus, the cooling capacity and the efficiency are increased, and the no-load temperature is decreased. The mechanism of the waiting time is discussed with numerical analysis and verified by experiments. Experiments show that there is an optimum waiting time for the no-load temperature, the cooling capacity and the efficiency, respectively. The no-load temperature of 40.3 K was achieved with a 90° waiting time. The cooling capacity of 58 W at 80 K was achieved with a 60° waiting time. The no-load temperature of 45.1 K and the cooling capacity of 45 W at 80 K were achieved with a 1° waiting time.
Do waiting times affect health outcomes? Evidence from coronary bypass.
Moscelli, Giuseppe; Siciliani, Luigi; Tonei, Valentina
2016-07-01
Long waiting times for non-emergency services are a feature of several publicly-funded health systems. A key policy concern is that long waiting times may worsen health outcomes: when patients receive treatment, their health condition may have deteriorated and health gains reduced. This study investigates whether patients in need of coronary bypass with longer waiting times are associated with poorer health outcomes in the English National Health Service over 2000-2010. Exploiting information from the Hospital Episode Statistics (HES), we measure health outcomes with in-hospital mortality and 28-day emergency readmission following discharge. Our results, obtained combining hospital fixed effects and instrumental variable methods, find no evidence of waiting times being associated with higher in-hospital mortality and weak association between waiting times and emergency readmission following a surgery. The results inform the debate on the relative merits of different types of rationing in healthcare systems. They are to some extent supportive of waiting times as an acceptable rationing mechanism, although further research is required to explore whether long waiting times affect other aspects of individuals' life. Copyright © 2016 Elsevier Ltd. All rights reserved.
Waiting endurance time estimation of electric two-wheelers at signalized intersections.
Huan, Mei; Yang, Xiao-bao
2014-01-01
The paper proposed a model for estimating waiting endurance times of electric two-wheelers at signalized intersections using survival analysis method. Waiting duration times were collected by video cameras and they were assigned as censored and uncensored data to distinguish between normal crossing and red-light running behavior. A Cox proportional hazard model was introduced, and variables revealing personal characteristics and traffic conditions were defined as covariates to describe the effects of internal and external factors. Empirical results show that riders do not want to wait too long to cross intersections. As signal waiting time increases, electric two-wheelers get impatient and violate the traffic signal. There are 12.8% of electric two-wheelers with negligible wait time. 25.0% of electric two-wheelers are generally nonrisk takers who can obey the traffic rules after waiting for 100 seconds. Half of electric two-wheelers cannot endure 49.0 seconds or longer at red-light phase. Red phase time, motor vehicle volume, and conformity behavior have important effects on riders' waiting times. Waiting endurance times would decrease with the longer red-phase time, the lower traffic volume, or the bigger number of other riders who run against the red light. The proposed model may be applicable in the design, management and control of signalized intersections in other developing cities.
Waiting Endurance Time Estimation of Electric Two-Wheelers at Signalized Intersections
Huan, Mei; Yang, Xiao-bao
2014-01-01
The paper proposed a model for estimating waiting endurance times of electric two-wheelers at signalized intersections using survival analysis method. Waiting duration times were collected by video cameras and they were assigned as censored and uncensored data to distinguish between normal crossing and red-light running behavior. A Cox proportional hazard model was introduced, and variables revealing personal characteristics and traffic conditions were defined as covariates to describe the effects of internal and external factors. Empirical results show that riders do not want to wait too long to cross intersections. As signal waiting time increases, electric two-wheelers get impatient and violate the traffic signal. There are 12.8% of electric two-wheelers with negligible wait time. 25.0% of electric two-wheelers are generally nonrisk takers who can obey the traffic rules after waiting for 100 seconds. Half of electric two-wheelers cannot endure 49.0 seconds or longer at red-light phase. Red phase time, motor vehicle volume, and conformity behavior have important effects on riders' waiting times. Waiting endurance times would decrease with the longer red-phase time, the lower traffic volume, or the bigger number of other riders who run against the red light. The proposed model may be applicable in the design, management and control of signalized intersections in other developing cities. PMID:24895659
[Waiting time for the first colposcopic examination in women with abnormal Papanicolaou test].
Nascimento, Maria Isabel do; Rabelo, Irene Machado Moraes Alvarenga; Cardoso, Fabrício Seabra Polidoro; Musse, Ricardo Neif Vieira
2015-08-01
To evaluate the waiting times before obtaining the first colposcopic examination for women with abnormal Papanicolaou smears. Retrospective cohort study conducted on patients who required a colposcopic examination to clarify an abnormal pap test, between 2002 January and 2008 August, in a metropolitan region of Brazil. The waiting times were defined as: Total Waiting Time (interval between the date of the pap test result and the date of the first colposcopic examination); Partial A Waiting Time (interval between the date of the pap test result and the date of referral); Partial B Waiting Time (interval between the date of referral and the date of the first colposcopic examination). Means, medians, relative and absolute frequencies were calculated. The Kruskal-Wallis test and Pearson's chi-square test were used to determine statistical significance. A total of 1,544 women with mean of age of 34 years (SD=12.6 years) were analyzed. Most of them had access to colposcopic examination within 30 days (65.8%) or 60 days (92.8%) from referral. Mean Total Waiting Time, Partial A Waiting Time, and Partial B Waiting Time were 94.5 days (SD=96.8 days), 67.8 days (SD=95.3 days) and 29.2 days (SD=35.1 days), respectively. A large part of the women studied had access to colposcopic examination within 60 days after referral, but Total waiting time was long. Measures to reduce the waiting time for obtaining the first colposcopic examination can help to improve the quality of care in the context of cervical cancer control in the region, and ought to be addressed at the phase between the date of the pap test results and the date of referral to the teaching hospital.
Mehra, Payal
2016-08-08
Purpose - The purpose of this paper is to evaluate the impact of extended waiting time on patients' perceptions of provider communication skills and in-clinic satisfaction, in three major cities in India. Design/methodology/approach - In total, 625 patients were interviewed. The multivariate general linear model was used to determine the causality and relationship between the independent and the dependent variable. A moderation analysis was also conducted to assess waiting time role as a potential moderator in doctor-patient communication. Findings - Results show that patients with higher waiting time were less satisfied with health care quality. Male patients and patients of male providers were more affected by extended waiting time than female patients and patients of female providers. The advanced regression analysis, however, suggests weak support for waiting time and its effect on overall satisfaction with clinic quality. Waiting time did not moderate the relationship between satisfaction with dominant communication style, and overall satisfaction at the outpatient clinic. Research limitations/implications - A cross-sectional study does not easily lend itself to explaining causality with certainty. Thus, sophisticated techniques, such as structural equation modelling may also be utilized to assess the influence of extended waiting time on satisfaction with healthcare at outpatient clinics. Practical implications - Findings are relevant for providers as the onus is on them to ensure patient satisfaction. They should initiate a workable waiting time assessment model at the operational level. Originality/value - There has been a relatively lesser focus on patient waiting time in patient-provider satisfaction studies. In India, this aspect is still vastly unexplored especially in the context of outpatient clinics. Gender wise pattern of patient satisfaction and waiting time is also missing in most studies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joseph, Ackeem; Herrera, David; Hijal, Tarek
We describe a method for predicting waiting times in radiation oncology. Machine learning is a powerful predictive modelling tool that benefits from large, potentially complex, datasets. The essence of machine learning is to predict future outcomes by learning from previous experience. The patient waiting experience remains one of the most vexing challenges facing healthcare. Waiting time uncertainty can cause patients, who are already sick and in pain, to worry about when they will receive the care they need. In radiation oncology, patients typically experience three types of waiting: Waiting at home for their treatment plan to be prepared Waiting inmore » the waiting room for daily radiotherapy Waiting in the waiting room to see a physician in consultation or follow-up These waiting periods are difficult for staff to predict and only rough estimates are typically provided, based on personal experience. In the present era of electronic health records, waiting times need not be so uncertain. At our centre, we have incorporated the electronic treatment records of all previously-treated patients into our machine learning model. We found that the Random Forest Regression model provides the best predictions for daily radiotherapy treatment waiting times (type 2). Using this model, we achieved a median residual (actual minus predicted value) of 0.25 minutes and a standard deviation residual of 6.5 minutes. The main features that generated the best fit model (from most to least significant) are: Allocated time, median past duration, fraction number and the number of treatment fields.« less
Bruni, Rebecca A; Laupacis, Andreas; Levinson, Wendy; Martin, Douglas K
2007-11-16
As no health system can afford to provide all possible services and treatments for the people it serves, each system must set priorities. Priority setting decision makers are increasingly involving the public in policy making. This study focuses on public engagement in a key priority setting context that plagues every health system around the world: wait list management. The purpose of this study is to describe and evaluate priority setting for the Ontario Wait Time Strategy, with special attention to public engagement. This study was conducted at the Ontario Wait Time Strategy in Ontario, Canada which is part of a Federal-Territorial-Provincial initiative to improve access and reduce wait times in five areas: cancer, cardiac, sight restoration, joint replacements, and diagnostic imaging. There were two sources of data: (1) over 25 documents (e.g. strategic planning reports, public updates), and (2) 28 one-on-one interviews with informants (e.g. OWTS participants, MOHLTC representatives, clinicians, patient advocates). Analysis used a modified thematic technique in three phases: open coding, axial coding, and evaluation. The Ontario Wait Time Strategy partially meets the four conditions of 'accountability for reasonableness'. The public was not directly involved in the priority setting activities of the Ontario Wait Time Strategy. Study participants identified both benefits (supporting the initiative, experts of the lived experience, a publicly funded system and sustainability of the healthcare system) and concerns (personal biases, lack of interest to be involved, time constraints, and level of technicality) for public involvement in the Ontario Wait Time Strategy. Additionally, the participants identified concern for the consequences (sustainability, cannibalism, and a class system) resulting from the Ontario Wait Times Strategy. We described and evaluated a wait time management initiative (the Ontario Wait Time Strategy) with special attention to public engagement, and provided a concrete plan to operationalize a strategy for improving public involvement in this, and other, wait time initiatives.
Bruni, Rebecca A; Laupacis, Andreas; Levinson, Wendy; Martin, Douglas K
2007-01-01
Background As no health system can afford to provide all possible services and treatments for the people it serves, each system must set priorities. Priority setting decision makers are increasingly involving the public in policy making. This study focuses on public engagement in a key priority setting context that plagues every health system around the world: wait list management. The purpose of this study is to describe and evaluate priority setting for the Ontario Wait Time Strategy, with special attention to public engagement. Methods This study was conducted at the Ontario Wait Time Strategy in Ontario, Canada which is part of a Federal-Territorial-Provincial initiative to improve access and reduce wait times in five areas: cancer, cardiac, sight restoration, joint replacements, and diagnostic imaging. There were two sources of data: (1) over 25 documents (e.g. strategic planning reports, public updates), and (2) 28 one-on-one interviews with informants (e.g. OWTS participants, MOHLTC representatives, clinicians, patient advocates). Analysis used a modified thematic technique in three phases: open coding, axial coding, and evaluation. Results The Ontario Wait Time Strategy partially meets the four conditions of 'accountability for reasonableness'. The public was not directly involved in the priority setting activities of the Ontario Wait Time Strategy. Study participants identified both benefits (supporting the initiative, experts of the lived experience, a publicly funded system and sustainability of the healthcare system) and concerns (personal biases, lack of interest to be involved, time constraints, and level of technicality) for public involvement in the Ontario Wait Time Strategy. Additionally, the participants identified concern for the consequences (sustainability, cannibalism, and a class system) resulting from the Ontario Wait Times Strategy. Conclusion We described and evaluated a wait time management initiative (the Ontario Wait Time Strategy) with special attention to public engagement, and provided a concrete plan to operationalize a strategy for improving public involvement in this, and other, wait time initiatives. PMID:18021393
NASA Astrophysics Data System (ADS)
Xiang, Yu; Tao, Cheng
2018-05-01
During the operation of the personal rapid transit system(PRT), the empty vehicle resources is distributed unevenly because of different passenger demand. In order to maintain the balance between supply and demand, and to meet the passenger needs of the ride, PRT empty vehicle resource allocation model is constructed based on the future demand forecasted by historical demand in this paper. The improved genetic algorithm is implied in distribution of the empty vehicle which can reduce the customers waiting time and improve the operation efficiency of the PRT system so that all passengers can take the PRT vehicles in the shortest time. The experimental result shows that the improved genetic algorithm can allocate the empty vehicle from the system level optimally, and realize the distribution of the empty vehicle resources reasonably in the system.
Parallel processing optimization strategy based on MapReduce model in cloud storage environment
NASA Astrophysics Data System (ADS)
Cui, Jianming; Liu, Jiayi; Li, Qiuyan
2017-05-01
Currently, a large number of documents in the cloud storage process employed the way of packaging after receiving all the packets. From the local transmitter this stored procedure to the server, packing and unpacking will consume a lot of time, and the transmission efficiency is low as well. A new parallel processing algorithm is proposed to optimize the transmission mode. According to the operation machine graphs model work, using MPI technology parallel execution Mapper and Reducer mechanism. It is good to use MPI technology to implement Mapper and Reducer parallel mechanism. After the simulation experiment of Hadoop cloud computing platform, this algorithm can not only accelerate the file transfer rate, but also shorten the waiting time of the Reducer mechanism. It will break through traditional sequential transmission constraints and reduce the storage coupling to improve the transmission efficiency.
Influence of positive distractions on children in two clinic waiting areas.
Pati, Debajyoti; Nanda, Upali
2011-01-01
To examine the influence of positive distraction on the behavior and activity of children in two clinic waiting areas. People spend a considerable proportion of time waiting in hospitals. Studies show that the quality of waiting environments influences the perception of quality of care and caregivers, that perception of waiting time is a better indicator of patient satisfaction than actual waiting time, and that the waiting environment contributes to the perception of wait time. In fact, the attractiveness of the physical environment in waiting areas has been shown to be significantly associated with higher perceived quality of care, less anxiety, and higher reported positive interaction with staff. Can positive distractions in waiting areas improve the waiting experience, as indicated by the behavior and activities of children waiting for treatment? Five distraction conditions were randomly introduced in the waiting area of the dental and cardiac clinics of a major pediatric tertiary care center through a single plasma screen intervention. The attention, behavior, and activities of waiting children were recorded. Data on 158 pediatric patients were collected over 12 days during December 2008 and January 2009. Data analysis shows that the introduction of distraction conditions was associated with more calm behavior and less fine and gross movement, suggesting significant calming effects associated with the distraction conditions. Data also suggest that positive distraction conditions are significant attention grabbers and could be an important contributor to improving the waiting experience for children in hospitals by improving environmental attractiveness.
A study of dynamic data placement for ATLAS distributed data management
NASA Astrophysics Data System (ADS)
Beermann, T.; Stewart, G. A.; Maettig, P.
2015-12-01
This contribution presents a study on the applicability and usefulness of dynamic data placement methods for data-intensive systems, such as ATLAS distributed data management (DDM). In this system the jobs are sent to the data, therefore having a good distribution of data is significant. Ways of forecasting workload patterns are examined which then are used to redistribute data to achieve a better overall utilisation of computing resources and to reduce waiting time for jobs before they can run on the grid. This method is based on a tracer infrastructure that is able to monitor and store historical data accesses and which is used to create popularity reports. These reports provide detailed summaries about data accesses in the past, including information about the accessed files, the involved users and the sites. From this past data it is possible to then make near-term forecasts for data popularity in the future. This study evaluates simple prediction methods as well as more complex methods like neural networks. Based on the outcome of the predictions a redistribution algorithm deletes unused replicas and adds new replicas for potentially popular datasets. Finally, a grid simulator is used to examine the effects of the redistribution. The simulator replays workload on different data distributions while measuring the job waiting time and site usage. The study examines how the average waiting time is affected by the amount of data that is moved, how it differs for the various forecasting methods and how that compares to the optimal data distribution.
Spot measurement of heart rate based on morphology of PhotoPlethysmoGraphic (PPG) signals.
Madhan Mohan, P; Nagarajan, V; Vignesh, J C
2017-02-01
Due to increasing health consciousness among people, it is imperative to have low-cost health care devices to measure the vital parameters like heart rate and arterial oxygen saturation (SpO 2 ). In this paper, an efficient heart rate monitoring algorithm based on the morphology of photoplethysmography (PPG) signals to measure the spot heart rate (HR) and its real-time implementation is proposed. The algorithm does pre-processing and detects the onsets and systolic peaks of the PPG signal to estimate the heart rate of the subject. Since the algorithm is based on the morphology of the signal, it works well when the subject is not moving, which is a typical test case. So, this algorithm is developed mainly to measure the heart rate at on-demand applications. Real-time experimental results indicate the heart rate accuracy of 99.5%, mean absolute percentage error (MAPE) of 1.65%, mean absolute error (MAE) of 1.18 BPM and reference closeness factor (RCF) of 0.988. The results further show that the average response time of the algorithm to give the spot HR is 6.85 s, so that the users need not wait longer to see their HR. The hardware implementation results show that the algorithm only requires 18 KBytes of total memory and runs at high speed with 0.85 MIPS. So, this algorithm can be targeted to low-cost embedded platforms.
The relationship between educational attainment and waiting time among the elderly in Norway.
Carlsen, Fredrik; Kaarboe, Oddvar Martin
2015-11-01
We investigate whether educational attainment affects waiting time of elderly patients in somatic hospitals. We consider three distinct pathways; that patients with different educational attainment have different disease patterns, that patients with different levels of education receive treatments at different hospitals, and that patient choice and supply of local health services within hospital catchment areas explain unequal waiting time of different educational groups. We find evidence of an educational gradient in waiting time for male patients, but not for female patients. Conditional on age, male patients with tertiary education wait 45% shorter than male patients with secondary or primary education. The first pathway is not quantitatively important as controlling for disease patters has little effect on relative waiting times. The second pathway is important. Relative to patients with primary education, variation in waiting time and education level across local hospitals contributes to higher waiting time for male patients with secondary education and female patients with secondary or tertiary education and lower waiting time for male patients with tertiary education. These effects are in the order of 15-20%. The third pathway is also quantitatively important. The educational gradients within catchment areas disappear when we control for travel distance and supply of private specialists. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Individual and system influences on waiting time for substance abuse treatment.
Carr, Carey J A; Xu, Jiangmin; Redko, Cristina; Lane, D Timothy; Rapp, Richard C; Goris, John; Carlson, Robert G
2008-03-01
Waiting time is a contemporary reality of many drug abuse treatment programs, resulting in substantial problems for substance users and society. Individual and system factors that influence waiting time are diverse and may vary at different points in the treatment continuum. This study assessed waiting time preceding clinical assessment at a centralized intake unit and during the period after the assessment but before treatment entry. The present study included 577 substance abusers who were enrolled in a large clinical trial of two brief treatment interventions in a midsize metropolitan area in Ohio. Bivariate analyses identified individual and system factors that influenced preassessment and postassessment waiting time, as well as total wait to treatment services. Multivariate analyses demonstrated that longer wait time for an assessment is influenced by being court referred, less belief in having a substance abuse problem, and less desire for change. A shorter wait to actually enter treatment is predicted by having a case manager, being more ready for treatment, and having less severe employment and alcohol problems. The different influences present during the two waiting periods suggest that assessment and treatment programs need to implement system changes and entry enhancement interventions that are specific to the needs of substance abusers at each waiting period.
Equity in specialist waiting times by socioeconomic groups: evidence from Spain.
Abásolo, Ignacio; Negrín-Hernández, Miguel A; Pinilla, Jaime
2014-04-01
In countries with publicly financed health care systems, waiting time--rather than price--is the rationing mechanism for access to health care services. The normative statement underlying such a rationing device is that patients should wait according to need and irrespective of socioeconomic status or other non-need characteristics. The aim of this paper is to test empirically that waiting times for publicly funded specialist care do not depend on patients' socioeconomic status. Waiting times for specialist care can vary according to the type of medical specialty, type of consultation (review or diagnosis) and the region where patients' reside. In order to take into account such variability, we use Bayesian random parameter models to explain waiting times for specialist care in terms of need and non-need variables. We find that individuals with lower education and income levels wait significantly more time than their counterparts.
General practice cooperatives: long waiting times for home visits due to long distances?
Giesen, Paul; van Lin, Nieke; Mokkink, Henk; van den Bosch, Wil; Grol, Richard
2007-01-01
Background The introduction of large-scale out-of-hours GP cooperatives has led to questions about increased distances between the GP cooperatives and the homes of patients and the increasing waiting times for home visits in urgent cases. We studied the relationship between the patient's waiting time for a home visit and the distance to the GP cooperative. Further, we investigated if other factors (traffic intensity, home visit intensity, time of day, and degree of urgency) influenced waiting times. Methods Cross-sectional study at four GP cooperatives. We used variance analysis to calculate waiting times for various categories of traffic intensity, home visit intensity, time of day, and degree of urgency. We used multiple logistic regression analysis to calculate to what degree these factors affected the ability to meet targets in urgent cases. Results The average waiting time for 5827 consultations was 30.5 min. Traffic intensity, home visit intensity, time of day and urgency of the complaint all seemed to affect waiting times significantly. A total of 88.7% of all patients were seen within 1 hour. In the case of life-threatening complaints (U1), 68.8% of the patients were seen within 15 min, and 95.6% of those with acute complaints (U2) were seen within 1 hour. For patients with life-threatening complaints (U1) the percentage of visits that met the time target of 15 minuts decreased from 86.5% (less than 2.5 km) to 16.7% (equals or more than 20 km). Discussion and conclusion Although home visits waiting times increase with increasing distance from the GP cooperative, it appears that traffic intensity, home visit intensity, and urgency also influence waiting times. For patients with life-threatening complaints waiting times increase sharply with the distance. PMID:17295925
General practice cooperatives: long waiting times for home visits due to long distances?
Giesen, Paul; van Lin, Nieke; Mokkink, Henk; van den Bosch, Wil; Grol, Richard
2007-02-12
The introduction of large-scale out-of-hours GP cooperatives has led to questions about increased distances between the GP cooperatives and the homes of patients and the increasing waiting times for home visits in urgent cases. We studied the relationship between the patient's waiting time for a home visit and the distance to the GP cooperative. Further, we investigated if other factors (traffic intensity, home visit intensity, time of day, and degree of urgency) influenced waiting times. Cross-sectional study at four GP cooperatives. We used variance analysis to calculate waiting times for various categories of traffic intensity, home visit intensity, time of day, and degree of urgency. We used multiple logistic regression analysis to calculate to what degree these factors affected the ability to meet targets in urgent cases. The average waiting time for 5827 consultations was 30.5 min. Traffic intensity, home visit intensity, time of day and urgency of the complaint all seemed to affect waiting times significantly. A total of 88.7% of all patients were seen within 1 hour. In the case of life-threatening complaints (U1), 68.8% of the patients were seen within 15 min, and 95.6% of those with acute complaints (U2) were seen within 1 hour. For patients with life-threatening complaints (U1) the percentage of visits that met the time target of 15 minutes decreased from 86.5% (less than 2.5 km) to 16.7% (equals or more than 20 km). Although home visits waiting times increase with increasing distance from the GP cooperative, it appears that traffic intensity, home visit intensity, and urgency also influence waiting times. For patients with life-threatening complaints waiting times increase sharply with the distance.
A Sarsa(λ)-based control model for real-time traffic light coordination.
Zhou, Xiaoke; Zhu, Fei; Liu, Quan; Fu, Yuchen; Huang, Wei
2014-01-01
Traffic problems often occur due to the traffic demands by the outnumbered vehicles on road. Maximizing traffic flow and minimizing the average waiting time are the goals of intelligent traffic control. Each junction wants to get larger traffic flow. During the course, junctions form a policy of coordination as well as constraints for adjacent junctions to maximize their own interests. A good traffic signal timing policy is helpful to solve the problem. However, as there are so many factors that can affect the traffic control model, it is difficult to find the optimal solution. The disability of traffic light controllers to learn from past experiences caused them to be unable to adaptively fit dynamic changes of traffic flow. Considering dynamic characteristics of the actual traffic environment, reinforcement learning algorithm based traffic control approach can be applied to get optimal scheduling policy. The proposed Sarsa(λ)-based real-time traffic control optimization model can maintain the traffic signal timing policy more effectively. The Sarsa(λ)-based model gains traffic cost of the vehicle, which considers delay time, the number of waiting vehicles, and the integrated saturation from its experiences to learn and determine the optimal actions. The experiment results show an inspiring improvement in traffic control, indicating the proposed model is capable of facilitating real-time dynamic traffic control.
Finding long chains in kidney exchange using the traveling salesman problem.
Anderson, Ross; Ashlagi, Itai; Gamarnik, David; Roth, Alvin E
2015-01-20
As of May 2014 there were more than 100,000 patients on the waiting list for a kidney transplant from a deceased donor. Although the preferred treatment is a kidney transplant, every year there are fewer donors than new patients, so the wait for a transplant continues to grow. To address this shortage, kidney paired donation (KPD) programs allow patients with living but biologically incompatible donors to exchange donors through cycles or chains initiated by altruistic (nondirected) donors, thereby increasing the supply of kidneys in the system. In many KPD programs a centralized algorithm determines which exchanges will take place to maximize the total number of transplants performed. This optimization problem has proven challenging both in theory, because it is NP-hard, and in practice, because the algorithms previously used were unable to optimally search over all long chains. We give two new algorithms that use integer programming to optimally solve this problem, one of which is inspired by the techniques used to solve the traveling salesman problem. These algorithms provide the tools needed to find optimal solutions in practice.
Finding long chains in kidney exchange using the traveling salesman problem
Anderson, Ross; Ashlagi, Itai; Gamarnik, David; Roth, Alvin E.
2015-01-01
As of May 2014 there were more than 100,000 patients on the waiting list for a kidney transplant from a deceased donor. Although the preferred treatment is a kidney transplant, every year there are fewer donors than new patients, so the wait for a transplant continues to grow. To address this shortage, kidney paired donation (KPD) programs allow patients with living but biologically incompatible donors to exchange donors through cycles or chains initiated by altruistic (nondirected) donors, thereby increasing the supply of kidneys in the system. In many KPD programs a centralized algorithm determines which exchanges will take place to maximize the total number of transplants performed. This optimization problem has proven challenging both in theory, because it is NP-hard, and in practice, because the algorithms previously used were unable to optimally search over all long chains. We give two new algorithms that use integer programming to optimally solve this problem, one of which is inspired by the techniques used to solve the traveling salesman problem. These algorithms provide the tools needed to find optimal solutions in practice. PMID:25561535
Yadav, Geeta; Goldberg, Hanna R; Barense, Morgan D; Bell, Chaim M
2016-01-01
Though previous work has examined some aspects of the dermatology workforce shortage and access to dermatologic care, little research has addressed the effect of rising interest in cosmetic procedures on access to medical dermatologic care. Our objective was to determine the wait times for Urgent and Non-Urgent medical dermatologic care and Cosmetic dermatology services at a population level and to examine whether wait times for medical care are affected by offering cosmetic services. A population-wide survey of dermatology practices using simulated calls asking for the earliest appointment for a Non-Urgent, Urgent and Cosmetic service. Response rates were greater than 89% for all types of care. Wait times across all types of care were significantly different from each other (all P < 0.05). Cosmetic care was associated with the shortest wait times (3.0 weeks; Interquartile Range (IQR) = 0.4-3.4), followed by Urgent care (9.0 weeks; IQR = 2.1-12.9), then Non-Urgent Care (12.7 weeks; IQR = 4.4-16.4). Wait times for practices offering only Urgent care were not different from practices offering both Urgent and Cosmetic care (10.3 vs. 7.0 weeks). Longer wait times and greater variation for Urgent and Non-Urgent dermatologic care and shorter wait times and less variation for Cosmetic care. Wait times were significantly longer in regions with lower dermatologist density. Provision of Cosmetic services did not increase wait times for Urgent care. These findings suggest an overall dermatology workforce shortage and a need for a more streamlined referral system for dermatologic care.
Eskander, Antoine; Devins, Gerald M; Freeman, Jeremy; Wei, Alice C; Rotstein, Lorne; Chauhan, Nitin; Sawka, Anna M; Brown, Dale; Irish, Jonathan; Gilbert, Ralph; Gullane, Patrick; Higgins, Kevin; Enepekides, Danny; Goldstein, David
2013-02-01
Patients with thyroid pathology tend have longer surgical wait times. Uncertainty during this wait can have negative psychologically impact. This study aims to determine the degree of psychological morbidity in patients waiting for thyroid surgery. Prospectively assessing patients pre- and postoperative psychological morbidity (level 2c). Patients waiting for thyroidectomy were mailed a sociodemographic and four psychological morbidity questionnaires: Impact of Events Scale-Revised (IES-R), Illness Intrusiveness Ratings Scale (IIRS), Perceived Stress Scale (PSS) and Hospital Anxiety and Depression Scale (HADS). We assessed whether anxiety was related to length of wait and a number of clinical/sociodemographic factors. We achieved a 53% response rate over a 3-year period, with 176 patients providing complete preoperative data; and 74 (42%) completed postoperative data. The average age was 53 (± 12) years; 82% were female. Respondents with a suspicious or known malignancy waited an average of 107 days while those with benign neoplastic biopsies waited an average of 218 days for thyroidectomy. Respondents reported substantial psychological morbidity with high IES-R, IIRS, PSS, and HADS scores. There was no significant association between psychological morbidity and wait times, clinical or sociodemographic factors. Postoperative anxiety decreased significantly in all psychological morbidity measures except for the IIRS. Patients waiting for thyroid surgery have mild to moderate psychological morbidity and long wait times for surgery. These appear not to be related. Psychological morbidity decreases after surgery. Reducing wait time can potentially reduce the time that patients have to live with unnecessary stress and anxiety. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.
Llewellyn-Thomas, H; Thiel, E; Paterson, M; Naylor, D
1999-04-01
To elicit patients' maximal acceptable waiting times (MAWT) for non-urgent coronary artery bypass grafting (CABG), and to determine if MAWT is related to prior expectations of waiting times, symptom burden, expected relief, or perceived risks of myocardial infarction while waiting. Seventy-two patients on an elective CABG waiting list chose between two hypothetical but plausible options: a 1-month wait with 2% risk of surgical mortality, and a 6-month wait with 1% risk of surgical mortality. Waiting time in the 6-month option was varied up if respondents chose the 6-month/lower risk option, and down if they chose the 1-month/higher risk option, until the MAWT switch point was reached. Patients also reported their expected waiting time, perceived risks of myocardial infarction while waiting, current function, expected functional improvement and the value of that improvement. Only 17 (24%) patients chose the 6-month/1% risk option, while 55 (76%) chose the 1-month/2% risk option. The median MAWT was 2 months; scores ranged from 1 to 12 months (with two outliers). Many perceived high cumulative risks of myocardial infarction if waiting for 1 (upper quartile, > or = 1.45%) or 6 (upper quartile, > or = 10%) months. However, MAWT scores were related only to expected waiting time (r = 0.47; P < 0.0001). Most patients reject waiting 6 months for elective CABG, even if offered along with a halving in surgical mortality (from 2% to 1%). Intolerance for further delay seems to be determined primarily by patients' attachment to their scheduled surgical dates. Many also have severely inflated perceptions of their risk of myocardial infarction in the queue. These results suggest a need for interventions to modify patients' inaccurate risk perceptions, particularly if a scheduled surgical date must be deferred.
Parental satisfaction with paediatric care, triage and waiting times.
Fitzpatrick, Nicholas; Breen, Daniel T; Taylor, James; Paul, Eldho; Grosvenor, Robert; Heggie, Katrina; Mahar, Patrick D
2014-04-01
The present study aims to determine parental and guardian's perceptions of paediatric emergency care and satisfaction with care, waiting times and triage category in a community ED. A structured questionnaire was provided to parents or guardians of paediatric patients presenting to emergency. The survey evaluated parent perceptions of waiting time, environment/facilities, professionalism and communication skills of staff and overall satisfaction of care. One hundred and thirty-three completed questionnaires were received from parents of paediatric patients. Responses were overall positive with respect to the multiple domains assessed. Parents generally considered waiting times to be appropriate and consistent with triage categories. Overall satisfaction was not significantly different for varying treatment or waiting times. Patients triaged as semi-urgent were of the opinion that waiting times were less appropriate than urgent, less-urgent or non-urgent patients. On the basis of the present study, patient perceptions and overall satisfaction of care does not appear to be primarily influenced by time spent waiting or receiving treatment. Attempts made at the triage process to ensure that semi-urgent patients have reasonable expectations of waiting times might provide an opportunity to improve these patients' expectations and perceptions. © 2014 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.
2009-01-01
Background There is an ongoing debate in Germany about the assumption that patients with private health insurance (PHI) benefit from better access to medical care, including shorter waiting times (Lüngen et al. 2008), compared to patients with statutory health insurance (SHI). Problem Existing analyses of the determinants for waiting times in Germany are a) based on patient self-reports and b) do not cover the inpatient sector. This paper aims to fill both gaps by (i) generating new primary data and (ii) analyzing waiting times in German hospitals. Methods We requested individual appointments from 485 hospitals within an experimental study design, allowing us to analyze the impact of PHI versus SHI on waiting times (Asplin et al. 2005). Results In German acute care hospitals patients with PHI have significantly shorter waiting times than patients with SHI. Conclusion Discrimination in waiting times by insurance status does occur in the German acute hospital sector. Since there is very little transparency in treatment quality in Germany, we do not know whether discrimination in waiting times leads to discrimination in the quality of treatment. This is an important issue for future research. PMID:20025744
Outpatient Office Wait Times And Quality Of Care For Medicaid Patients.
Oostrom, Tamar; Einav, Liran; Finkelstein, Amy
2017-05-01
The time patients spend in a doctor's waiting room prior to a scheduled appointment is an important component of the quality of the overall health care experience. We analyzed data on twenty-one million outpatient visits obtained from electronic health record systems, which allowed us to measure time spent in the waiting room beyond the scheduled appointment time. Median wait time was a little more than four minutes. Almost one-fifth of visits had waits longer than twenty minutes, and 10 percent were more than thirty minutes. Waits were shorter for early-morning appointments, for younger patients, and at larger practices. Median wait time was 4.1 minutes for privately insured patients and 4.6 minutes for Medicaid patients. After adjustment for patient and appointment characteristics, Medicaid patients were 20 percent more likely than the privately insured patients to wait longer than twenty minutes, with most of this disparity explained by differences in practices and providers they saw. Wait times for Medicaid patients relative to privately insured patients were longer in states with relatively lower Medicaid reimbursement rates. The study complements other work that suggests that Medicaid patients face some additional barriers in the receipt of care. Project HOPE—The People-to-People Health Foundation, Inc.
Molinié, F; Leux, C; Delafosse, P; Ayrault-Piault, S; Arveux, P; Woronoff, A S; Guizard, A V; Velten, M; Ganry, O; Bara, S; Daubisse-Marliac, L; Tretarre, B
2013-10-01
Waiting times are key indicators of a health's system performance, but are not routinely available in France. We studied waiting times for diagnosis and treatment according to patients' characteristics, tumours' characteristics and medical management options in a sample of 1494 breast cancers recorded in population-based registries. The median waiting time from the first imaging detection to the treatment initiation was 34 days. Older age, co-morbidity, smaller size of tumour, detection by organised screening, biopsy, increasing number of specimens removed, multidisciplinary consulting meetings and surgery as initial treatment were related to increased waiting times in multivariate models. Many of these factors were related to good practices guidelines. However, the strong influence of organised screening programme and the disparity of waiting times according to geographical areas were of concern. Better scheduling of diagnostic tests and treatment propositions should improve waiting times in the management of breast cancer in France. Copyright © 2013 Elsevier Ltd. All rights reserved.
Waiting times in the ambulatory sector--the case of chronically ill patients.
Sundmacher, Leonie; Kopetsch, Thomas
2013-09-10
First, the influence of determinants on the waiting times of chronically ill patients in the ambulatory sector is investigated. The determinants are subdivided into four groups: (1) need, (2) socio-economic factors, (3) health system and (4) patient time pressures. Next, the influence of waiting times on the annual number of consultations is examined to assess whether the existing variation in waiting times influences the frequency of medical examinations. The waiting times of chronically ill patients are analysed since regular ambulatory care for this patient group could both improve treatment outcomes and lower costs. Individual data from the 2010 Representative Survey conducted by the National Association of Statutory Health Insurance Physicians (KBV) together with regional data from the Federal Office of Construction and Regional Planning. This is a retrospective observational study. The dependent variables are waiting times in the ambulatory sector and the number of consultations of General Practitioners (GPs) and specialist physicians in the year 2010. The explanatory variables of interest are 'need' and 'health system' in the first model and 'length of waiting times' in the second. Negative binomial models with random effects are used to estimate the incidence rate ratios of increased waiting times and number of consultations. Subsequently, the models are stratified by urban and rural areas. In the pooled regression the factor 'privately insured' shortens the waiting time for treatment by a specialist by approximately 28% (about 3 days) in comparison with members of the statutory health insurance system. The category of insurance has no influence on the number of consultations of GPs. In addition, the regression results stratified by urban and rural areas show that in urban areas the factor 'privately insured' reduces the waiting time for specialists by approximately 35% (about 3.3 days) while in rural areas there is no evidence of statistical influence. In neither of the models, however, does the waiting time have a documentable effect on the number of consultations in the ambulatory sector. In our random sample, characteristics of the health care system have an influence on the waiting time for specialists, but the waiting time has no documentable effect on the number of consultations in the ambulatory sector. In the present analysis this applies to consultations of both GPs and specialists. Nevertheless, it does not rule out the possibility that the length of waiting times might influence the treatment outcomes of certain patient populations.
Ward, Paul R; Rokkas, Philippa; Cenko, Clinton; Pulvirenti, Mariastella; Dean, Nicola; Carney, A Simon; Meyer, Samantha
2017-05-05
Waiting times for hospital appointments, treatment and/or surgery have become a major political and health service problem, leading to national maximum waiting times and policies to reduce waiting times. Quantitative studies have documented waiting times for various types of surgery and longer waiting times in public vs private hospitals. However, very little qualitative research has explored patient experiences of waiting, how this compares between public and private hospitals, and the implications for trust in hospitals and healthcare professionals. The aim of this paper is to provide a deep understanding of the impact of waiting times on patient trust in public and private hospitals. A qualitative study in South Australia, including 36 in-depth interviews (18 from public and 18 from private hospitals). Data collection occurred in 2012-13, and data were analysed using pre-coding, followed by conceptual and theoretical categorisation. Participants differentiated between experiences of 'waiting for' (e.g. for specialist appointments and surgery) and 'waiting in' (e.g. in emergency departments and outpatient clinics) public and private hospitals. Whilst 'waiting for' public hospitals was longer than private hospitals, this was often justified and accepted by public patients (e.g. due to reduced government funding), therefore it did not lead to distrust of public hospitals. Private patients had shorter 'waiting for' hospital services, increasing their trust in private hospitals and distrust of public hospitals. Public patients also recounted many experiences of longer 'waiting in' public hospitals, leading to frustration and anxiety, although they rarely blamed or distrusted the doctors or nurses, instead blaming an underfunded system and over-worked staff. Doctors and nurses were seen to be doing their best, and therefore trustworthy. Although public patients experienced longer 'waiting for' and 'waiting in' public hospitals, it did not lead to widespread distrust in public hospitals or healthcare professionals. Private patients recounted largely positive stories of reduced 'waiting for' and 'waiting in' private hospitals, and generally distrusted public hospitals. The continuing trust by public patients in the face of negative experiences may be understood as a form of exchange trust norm, in which institutional trust is based on base-level expectations of consistency and minimum standards of care and safety. The institutional trust by private patients may be understood as a form of communal trust norm, whereby trust is based on the additional and higher-level expectations of flexibility, reduced waiting and more time with healthcare professionals.
Identifying demand for health resources using waiting times information.
Blundell, R; Windmeijer, F
2000-09-01
In this paper the differences in average waiting times are utilized to identify the determinants of demand for health services. The equilibrium waiting time framework is used, but the full equilibrium assumption is relaxed by selecting areas with low waiting times and by estimating a (semi-)parametric selection model. Determinants of supply are used as instruments for the endogeneity of waiting times. A model for the demand for acute services at the ward level in the UK is estimated. The model estimates, and their implications for health service allocations in the UK, are contrasted against more standard allocation models. The present results show that it is critically important to account for rationing by waiting times when identifying needs from care utilization data. Copyright 2000 John Wiley & Sons, Ltd.
Decreasing Wait Times and Increasing Patient Satisfaction: A Lean Six Sigma Approach.
Godley, Mary; Jenkins, Jeanne B
2018-06-08
Patient satisfaction scores in the vascular interventional radiology department were low, especially related to wait times in registration and for tests/treatments, with low scores for intentions to recommend. The purpose of our quality improvement project was to decrease wait times and improve patient satisfaction using Lean Six Sigma's define, measure, analyze, improve, and control (DMAIC) framework with a pre-/postintervention design. There was a statistically significant decrease in wait times (P < .0019) and an increase in patient satisfaction scores in 3 areas: registration wait times (from 17 to 99 percentiles), test/treatment (from 19 to 60 percentiles), and likelihood to recommend (from 6 to 97 percentiles). Lean Six Sigma was an effective framework for use in decreasing wait times and improving patient satisfaction.
High emergency organ allocation rule in lung transplantation: a simulation study.
Riou, Julien; Boëlle, Pierre-Yves; Christie, Jason D; Thabut, Gabriel
2017-10-01
The scarcity of suitable organ donors leads to protracted waiting times and mortality in patients awaiting lung transplantation. This study aims to assess the short- and long-term effects of a high emergency organ allocation policy on the outcome of lung transplantation. We developed a simulation model of lung transplantation waiting queues under two allocation strategies, based either on waiting time only or on additional criteria to prioritise the sickest patients. The model was informed by data from the United Network for Organ Sharing. We compared the impact of these strategies on waiting time, waiting list mortality and overall survival in various situations of organ scarcity. The impact of a high emergency allocation strategy depends largely on the organ supply. When organ supply is sufficient (>95 organs per 100 patients), it may prevent a small number of early deaths (1 year survival: 93.7% against 92.4% for waiting time only) without significant impact on waiting times or long-term survival. When the organ/recipient ratio is lower, the benefits in early mortality are larger but are counterbalanced by a dramatic increase of the size of the waiting list. Consequently, we observed a progressive increase of mortality on the waiting list (although still lower than with waiting time only), a deterioration of patients' condition at transplant and a decrease of post-transplant survival times. High emergency organ allocation is an effective strategy to reduce mortality on the waiting list, but causes a disruption of the list equilibrium that may have detrimental long-term effects in situations of significant organ scarcity.
High emergency organ allocation rule in lung transplantation: a simulation study
Boëlle, Pierre-Yves; Christie, Jason D.; Thabut, Gabriel
2017-01-01
The scarcity of suitable organ donors leads to protracted waiting times and mortality in patients awaiting lung transplantation. This study aims to assess the short- and long-term effects of a high emergency organ allocation policy on the outcome of lung transplantation. We developed a simulation model of lung transplantation waiting queues under two allocation strategies, based either on waiting time only or on additional criteria to prioritise the sickest patients. The model was informed by data from the United Network for Organ Sharing. We compared the impact of these strategies on waiting time, waiting list mortality and overall survival in various situations of organ scarcity. The impact of a high emergency allocation strategy depends largely on the organ supply. When organ supply is sufficient (>95 organs per 100 patients), it may prevent a small number of early deaths (1 year survival: 93.7% against 92.4% for waiting time only) without significant impact on waiting times or long-term survival. When the organ/recipient ratio is lower, the benefits in early mortality are larger but are counterbalanced by a dramatic increase of the size of the waiting list. Consequently, we observed a progressive increase of mortality on the waiting list (although still lower than with waiting time only), a deterioration of patients’ condition at transplant and a decrease of post-transplant survival times. High emergency organ allocation is an effective strategy to reduce mortality on the waiting list, but causes a disruption of the list equilibrium that may have detrimental long-term effects in situations of significant organ scarcity. PMID:29181383
The effect of early education on patient anxiety while waiting for elective cardiac catheterization.
Harkness, Karen; Morrow, Lydia; Smith, Kelly; Kiczula, Michele; Arthur, Heather M
2003-07-01
A supply-demand mismatch with respect to cardiac catheterization (CATH) often results in patients experiencing waiting times that vary from a few weeks to several months. Long delays can impose both physical and psychological distress for patients. The purpose of this study was to examine the effect of a psychoeducational nursing intervention at the beginning of the waiting period on patient anxiety during the waiting time for elective CATH. This was a 2-group randomized controlled trial. Intervention patients received a nurse-delivered, detailed information/education session within 2 weeks of being placed on the waiting list for elective CATH. Control group patients received usual care. The mean waiting time for CATH was 13.4+/-7.2 weeks, which did not differ between groups (P=0.509). Anxiety increased in both groups over the waiting time (P=0.028). Health-related quality of life deteriorated over the waiting time in both groups (P<0.05). On a visual analogue scale, there was a significant difference (P=0.002) between the intervention (4.0+/-2.7) and control (5.2+/-3.0) groups in self-reported anxiety 2 weeks prior to CATH. The waiting period prior to elective CATH has a negative impact on patients' perceived anxiety and quality of life and a simple intervention, provided at the beginning of the waiting period, may positively affect the experience of waiting.
An investigation of the impact of prolonged waiting times on blood donors in Ireland.
McKeever, T; Sweeney, M R; Staines, A
2006-02-01
The aim of this study was to investigate the impact of prolonged queuing times on blood donors, by measuring their satisfaction levels, and positive and negative affects. As donation times have increased over the past number of years within the Irish Blood Transfusion Service, this is an important issue to examine in a climate where voluntary donors are becoming scarce and demands on people's time are increasing. Eighty-five blood donors were sampled from one urban and one rural blood donor clinic. The respondents conducted a questionnaire by means of face-to-face interview, while waiting in the clinic. The questionnaire contained the Positive and Negative Affect Scale (PANAS), and a waiting satisfaction scale. Both actual and perceived waiting times of the donors were noted. Waiting time was found to be negatively related to satisfaction. Inexperienced donors expressed higher levels of negative affect than experienced donors. Urban donors were significantly more satisfied than rural donors. There was a significant difference in perceived waiting time between lone donors and those queuing in a group, with those waiting alone perceiving their wait as shorter. While all respondents stated that they intended to donate again, over one-third stated that prolonged waiting times would be their most likely deterrent. However, only 15% stated that long queuing times might actually prevent them from donating in the future, and almost all respondents said that they would recommend donation to a friend, despite long queuing times. Although our results show that the respondents were not satisfied with current waiting times, it did not seem to affect their future intentions to donate. These findings provide some optimism for the future of blood donation in Ireland, as they suggest a strong sense of commitment to donation within the population sampled. Future research could explore the application of 'the service industry' approach to waiting times to blood donation clinics.
Furushima, Daisuke; Yamada, Hiroshi; Kido, Michiko; Ohno, Yuko
2018-01-01
Improvement in patient waiting time in dispensing pharmacies is an important element for patient and pharmacists. The One-Dose Package (ODP) of medicines was implemented in Japan to support medicine adherence among elderly patients; however, it also contributed to increase in patient waiting times. Given the projected increase in ODP patients in the near future owing to rapid population aging, development of improved strategies is a key imperative. We conducted a cross-sectional survey at a single dispensing pharmacy to clarify the impact of ODP on patient waiting time. Further, we propose an improvement strategy developed with use of a discrete event simulation (DES) model. A total of 673 patients received pharmacy services during the study period. A two-fold difference in mean waiting time was observed between ODP and non-ODP patients (22.6 and 11.2 min, respectively). The DES model was constructed with input parameters estimated from observed data. Introduction of fully automated ODP (A-ODP) system was projected to reduce the waiting time for ODP patient by 0.5 times (from 23.1 to 11.5 min). Furthermore, assuming that 40% of non-ODP patients would transfer to ODP, the waiting time was predicted to increase to 56.8 min; however, introduction of the A-ODP system decreased the waiting time to 20.4 min. Our findings indicate that ODP is one of the elements that increases the waiting time and that it might become longer in the future. Introduction of the A-ODP system may be an effective strategy to improve waiting time.
Waiting for cataract surgery--effects of a maximum waiting-time guarantee.
Hanning, Marianne; Lundström, Mats
2007-01-01
To evaluate the effects of the Maximum Waiting-time Guarantee (MWG) policy for cataract surgery on volume, indications, waiting times and priority setting in Sweden. Comparison between 1993 and 1994, when the guarantee had been in force for one year, and 1998 and 1999, when the policy had been terminated for one year. Data from the National Cataract Registry covering 156,657 cataract operations for the years studied. The number of operations increased by 43% between the two study periods. Of this increase, 61% were patients with a visual acuity above 0.5 in the better eye, i.e. low-priority patients. Waiting times were longer for all patient categories in the later period and differences in waiting times between patients with differing priority diminished. Variations among the units in priority setting and waiting times were substantial, and increased after the Guarantee was terminated. The Guarantee with its explicit indications was an effective policy instrument to limit waiting times and improve access for patients with the greatest need. It is unlikely that the Guarantee caused any 'crowding out' of other patient groups. When the Guarantee was not in force, indications for surgery widened. This, however, resulted in longer waiting times for all patient groups. After the Guarantee was terminated, the already substantial differences in access and indications among ophthalmic units became even greater.
Optimizing phase to enhance optical trap stiffness.
Taylor, Michael A
2017-04-03
Phase optimization offers promising capabilities in optical tweezers, allowing huge increases in the applied forces, trap stiff-ness, or measurement sensitivity. One key obstacle to potential applications is the lack of an efficient algorithm to compute an optimized phase profile, with enhanced trapping experiments relying on slow programs that would take up to a week to converge. Here we introduce an algorithm that reduces the wait from days to minutes. We characterize the achievable in-crease in trap stiffness and its dependence on particle size, refractive index, and optical polarization. We further show that phase-only control can achieve almost all of the enhancement possible with full wavefront shaping; for instance phase control allows 62 times higher trap stiffness for 10 μm silica spheres in water, while amplitude control and non-trivial polarization further increase this by 1.26 and 1.01 respectively. This algorithm will facilitate future applications in optical trapping, and more generally in wavefront optimization.
Cho, Kyoung Won; Kim, Seong Min; Chae, Young Moon
2017-01-01
Objectives This research used queueing theory to analyze changes in outpatients' waiting times before and after the introduction of Electronic Medical Record (EMR) systems. Methods We focused on the exact drawing of two fundamental parameters for queueing analysis, arrival rate (λ) and service rate (µ), from digital data to apply queueing theory to the analysis of outpatients' waiting times. We used outpatients' reception times and consultation finish times to calculate the arrival and service rates, respectively. Results Using queueing theory, we could calculate waiting time excluding distorted values from the digital data and distortion factors, such as arrival before the hospital open time, which occurs frequently in the initial stage of a queueing system. We analyzed changes in outpatients' waiting times before and after the introduction of EMR using the methodology proposed in this paper, and found that the outpatients' waiting time decreases after the introduction of EMR. More specifically, the outpatients' waiting times in the target public hospitals have decreased by rates in the range between 44% and 78%. Conclusions It is possible to analyze waiting times while minimizing input errors and limitations influencing consultation procedures if we use digital data and apply the queueing theory. Our results verify that the introduction of EMR contributes to the improvement of patient services by decreasing outpatients' waiting time, or by increasing efficiency. It is also expected that our methodology or its expansion could contribute to the improvement of hospital service by assisting the identification and resolution of bottlenecks in the outpatient consultation process. PMID:28261529
Cho, Kyoung Won; Kim, Seong Min; Chae, Young Moon; Song, Yong Uk
2017-01-01
This research used queueing theory to analyze changes in outpatients' waiting times before and after the introduction of Electronic Medical Record (EMR) systems. We focused on the exact drawing of two fundamental parameters for queueing analysis, arrival rate (λ) and service rate (µ), from digital data to apply queueing theory to the analysis of outpatients' waiting times. We used outpatients' reception times and consultation finish times to calculate the arrival and service rates, respectively. Using queueing theory, we could calculate waiting time excluding distorted values from the digital data and distortion factors, such as arrival before the hospital open time, which occurs frequently in the initial stage of a queueing system. We analyzed changes in outpatients' waiting times before and after the introduction of EMR using the methodology proposed in this paper, and found that the outpatients' waiting time decreases after the introduction of EMR. More specifically, the outpatients' waiting times in the target public hospitals have decreased by rates in the range between 44% and 78%. It is possible to analyze waiting times while minimizing input errors and limitations influencing consultation procedures if we use digital data and apply the queueing theory. Our results verify that the introduction of EMR contributes to the improvement of patient services by decreasing outpatients' waiting time, or by increasing efficiency. It is also expected that our methodology or its expansion could contribute to the improvement of hospital service by assisting the identification and resolution of bottlenecks in the outpatient consultation process.
Yadav, Geeta; Goldberg, Hanna R.; Barense, Morgan D.; Bell, Chaim M.
2016-01-01
Background Though previous work has examined some aspects of the dermatology workforce shortage and access to dermatologic care, little research has addressed the effect of rising interest in cosmetic procedures on access to medical dermatologic care. Our objective was to determine the wait times for Urgent and Non-Urgent medical dermatologic care and Cosmetic dermatology services at a population level and to examine whether wait times for medical care are affected by offering cosmetic services. Methods A population-wide survey of dermatology practices using simulated calls asking for the earliest appointment for a Non-Urgent, Urgent and Cosmetic service. Results Response rates were greater than 89% for all types of care. Wait times across all types of care were significantly different from each other (all P < 0.05). Cosmetic care was associated with the shortest wait times (3.0 weeks; Interquartile Range (IQR) = 0.4–3.4), followed by Urgent care (9.0 weeks; IQR = 2.1–12.9), then Non-Urgent Care (12.7 weeks; IQR = 4.4–16.4). Wait times for practices offering only Urgent care were not different from practices offering both Urgent and Cosmetic care (10.3 vs. 7.0 weeks). Interpretation Longer wait times and greater variation for Urgent and Non-Urgent dermatologic care and shorter wait times and less variation for Cosmetic care. Wait times were significantly longer in regions with lower dermatologist density. Provision of Cosmetic services did not increase wait times for Urgent care. These findings suggest an overall dermatology workforce shortage and a need for a more streamlined referral system for dermatologic care. PMID:27632206
Sampalli, Tara; Desy, Michel; Dhir, Minakshi; Edwards, Lynn; Dickson, Robert; Blackmore, Gail
2015-04-05
Recognizing the significant impact of wait times for care for individuals with complex chronic conditions, we applied a LEAN methodology, namely - an adaptation of Value Stream Mapping (VSM) to meet the needs of people with multiple chronic conditions and to improve wait times without additional resources or funding. Over an 18-month time period, staff applied a patient-centric approach that included LEAN methodology of VSM to improve wait times to care. Our framework of evaluation was grounded in the needs and perspectives of patients and individuals waiting to receive care. Patient centric views were obtained through surveys such as Patient Assessment of Chronic Illness Care (PACIC) and process engineering based questions. In addition, LEAN methodology, VSM was added to identify non-value added processes contributing to wait times. The care team successfully reduced wait times to 2 months in 2014 with no wait times for care anticipated in 2015. Increased patient engagement and satisfaction are also outcomes of this innovative initiative. In addition, successful transformations and implementation have resulted in resource efficiencies without increase in costs. Patients have shown significant improvements in functional health following Integrated Chronic Care Service (ICCS) intervention. The methodology will be applied to other chronic disease management areas in Capital Health and the province. Wait times to care in the management of multimoribidities and other complex conditions can add a significant burden not only on the affected individuals but also on the healthcare system. In this study, a novel and modified LEAN methodology has been applied to embed the voice of the patient in care delivery processes and to reduce wait times to care in the management of complex chronic conditions. © 2015 by Kerman University of Medical Sciences.
Space, place and (waiting) time: reflections on health policy and politics.
Sheard, Sally
2018-02-19
Health systems have repeatedly addressed concerns about efficiency and equity by employing trans-national comparisons to draw out the strengths and weaknesses of specific policy initiatives. This paper demonstrates the potential for explicit historical analysis of waiting times for hospital treatment to add value to spatial comparative methodologies. Waiting times and the size of the lists of waiting patients have become key operational indicators. In the United Kingdom, as National Health Service (NHS) financial pressures intensified from the 1970s, waiting times have become a topic for regular public and political debate. Various explanations for waiting times include the following: hospital consultants manipulate NHS waiting lists to maintain their private practice; there is under-investment in the NHS; and available (and adequate) resources are being used inefficiently. Other countries have also experienced ongoing tensions between the public and private delivery of universal health care in which national and trans-national comparisons of waiting times have been regularly used. The paper discusses the development of key UK policies, and provides a limited Canadian comparative perspective, to explore wider issues, including whether 'waiting crises' were consciously used by policymakers, especially those brought into government to implement new economic and managerial strategies, to diminish the autonomy and authority of the medical professional in the hospital environment.
Statistical modeling of storm-level Kp occurrences
Remick, K.J.; Love, J.J.
2006-01-01
We consider the statistical modeling of the occurrence in time of large Kp magnetic storms as a Poisson process, testing whether or not relatively rare, large Kp events can be considered to arise from a stochastic, sequential, and memoryless process. For a Poisson process, the wait times between successive events occur statistically with an exponential density function. Fitting an exponential function to the durations between successive large Kp events forms the basis of our analysis. Defining these wait times by calculating the differences between times when Kp exceeds a certain value, such as Kp ??? 5, we find the wait-time distribution is not exponential. Because large storms often have several periods with large Kp values, their occurrence in time is not memoryless; short duration wait times are not independent of each other and are often clumped together in time. If we remove same-storm large Kp occurrences, the resulting wait times are very nearly exponentially distributed and the storm arrival process can be characterized as Poisson. Fittings are performed on wait time data for Kp ??? 5, 6, 7, and 8. The mean wait times between storms exceeding such Kp thresholds are 7.12, 16.55, 42.22, and 121.40 days respectively.
Numbers or apologies? Customer reactions to telephone waiting time fillers.
Munichor, Nira; Rafaeli, Anat
2007-03-01
The authors examined the effect of time perception and sense of progress in telephone queues on caller reactions to 3 telephone waiting time fillers: music, apologies, and information about location in the queue. In Study 1, conducted on 123 real calls, call abandonment was lowest, and call evaluations were most positive with information about location in the queue as the time filler. In Study 2, conducted with 83 participants who experienced a simulated telephone wait experience, sense of progress in the queue rather than perceived waiting time mediated the relationship between telephone waiting time filler and caller reactions. The findings provide insight for the management and design of telephone queues, as well as theoretical insight into critical cognitive processes that underlie telephone waiting, opening up an important new research agenda. (c) 2007 APA, all rights reserved.
Waiting times for hospital admissions: the impact of GP fundholding.
Propper, Carol; Croxson, Bronwyn; Shearer, Arran
2002-03-01
Waiting times for hospital care are a significant issue in the UK National Health Service (NHS). The reforms of the health service in 1990 gave a subset of family doctors (GP fundholders) both the ability to choose the hospital where their patients were treated and the means to pay for some services. One of the key factors influencing family doctors' choice of hospital was patient waiting time. However, without cash inducements, hospitals would get no direct reward from giving shorter waiting times to a subset of patients. Using a unique dataset, we investigate whether GP fundholders were able to secure shorter waiting times for their patients, whether they were able to do so in cases where they had no financial rewards to offer hospitals, and whether the impact of fundholding spilled over into shorter waiting times for all patients.
Determining prescription durations based on the parametric waiting time distribution.
Støvring, Henrik; Pottegård, Anton; Hallas, Jesper
2016-12-01
The purpose of the study is to develop a method to estimate the duration of single prescriptions in pharmacoepidemiological studies when the single prescription duration is not available. We developed an estimation algorithm based on maximum likelihood estimation of a parametric two-component mixture model for the waiting time distribution (WTD). The distribution component for prevalent users estimates the forward recurrence density (FRD), which is related to the distribution of time between subsequent prescription redemptions, the inter-arrival density (IAD), for users in continued treatment. We exploited this to estimate percentiles of the IAD by inversion of the estimated FRD and defined the duration of a prescription as the time within which 80% of current users will have presented themselves again. Statistical properties were examined in simulation studies, and the method was applied to empirical data for four model drugs: non-steroidal anti-inflammatory drugs (NSAIDs), warfarin, bendroflumethiazide, and levothyroxine. Simulation studies found negligible bias when the data-generating model for the IAD coincided with the FRD used in the WTD estimation (Log-Normal). When the IAD consisted of a mixture of two Log-Normal distributions, but was analyzed with a single Log-Normal distribution, relative bias did not exceed 9%. Using a Log-Normal FRD, we estimated prescription durations of 117, 91, 137, and 118 days for NSAIDs, warfarin, bendroflumethiazide, and levothyroxine, respectively. Similar results were found with a Weibull FRD. The algorithm allows valid estimation of single prescription durations, especially when the WTD reliably separates current users from incident users, and may replace ad-hoc decision rules in automated implementations. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Storage assignment optimization in a multi-tier shuttle warehousing system
NASA Astrophysics Data System (ADS)
Wang, Yanyan; Mou, Shandong; Wu, Yaohua
2016-03-01
The current mathematical models for the storage assignment problem are generally established based on the traveling salesman problem(TSP), which has been widely applied in the conventional automated storage and retrieval system(AS/RS). However, the previous mathematical models in conventional AS/RS do not match multi-tier shuttle warehousing systems(MSWS) because the characteristics of parallel retrieval in multiple tiers and progressive vertical movement destroy the foundation of TSP. In this study, a two-stage open queuing network model in which shuttles and a lift are regarded as servers at different stages is proposed to analyze system performance in the terms of shuttle waiting period (SWP) and lift idle period (LIP) during transaction cycle time. A mean arrival time difference matrix for pairwise stock keeping units(SKUs) is presented to determine the mean waiting time and queue length to optimize the storage assignment problem on the basis of SKU correlation. The decomposition method is applied to analyze the interactions among outbound task time, SWP, and LIP. The ant colony clustering algorithm is designed to determine storage partitions using clustering items. In addition, goods are assigned for storage according to the rearranging permutation and the combination of storage partitions in a 2D plane. This combination is derived based on the analysis results of the queuing network model and on three basic principles. The storage assignment method and its entire optimization algorithm method as applied in a MSWS are verified through a practical engineering project conducted in the tobacco industry. The applying results show that the total SWP and LIP can be reduced effectively to improve the utilization rates of all devices and to increase the throughput of the distribution center.
Xie, Zhenzhen; Or, Calvin
2017-01-01
The issue of long patient waits has attracted increasing public attention due to the negative effects of waiting on patients' satisfaction with health care. The present study examined the associations between actual waiting time, perceived acceptability of waiting time, actual service time, perceived acceptability of service time, actual visit duration, and the level of patient satisfaction with care. We conducted a cross-sectional time study and questionnaire survey of endocrinology outpatients visiting a major teaching hospital in China. Our results show that actual waiting time was negatively associated with patient satisfaction regarding several aspects of the care they received. Also, patients who were less satisfied with the sociocultural atmosphere and the identity-oriented approach to their care tended to perceive the amounts of time they spent waiting and receiving care as less acceptable. It is not always possible to prevent dissatisfaction with waiting, or to actually reduce waiting times by increasing resources such as increased staffing. However, several improvements in care services can be considered. Our suggestions include providing clearer, more transparent information to keep patients informed about the health care services that they may receive, and the health care professionals who are responsible for those services. We also suggest that care providers are encouraged to continue to show empathy and respect for patients, that patients are provided with private areas where they can talk with health professionals and no one can overhear, and that hospital staff treat the family members or friends who accompany patients in a courteous and friendly way.
Xie, Zhenzhen; Or, Calvin
2017-01-01
The issue of long patient waits has attracted increasing public attention due to the negative effects of waiting on patients’ satisfaction with health care. The present study examined the associations between actual waiting time, perceived acceptability of waiting time, actual service time, perceived acceptability of service time, actual visit duration, and the level of patient satisfaction with care. We conducted a cross-sectional time study and questionnaire survey of endocrinology outpatients visiting a major teaching hospital in China. Our results show that actual waiting time was negatively associated with patient satisfaction regarding several aspects of the care they received. Also, patients who were less satisfied with the sociocultural atmosphere and the identity-oriented approach to their care tended to perceive the amounts of time they spent waiting and receiving care as less acceptable. It is not always possible to prevent dissatisfaction with waiting, or to actually reduce waiting times by increasing resources such as increased staffing. However, several improvements in care services can be considered. Our suggestions include providing clearer, more transparent information to keep patients informed about the health care services that they may receive, and the health care professionals who are responsible for those services. We also suggest that care providers are encouraged to continue to show empathy and respect for patients, that patients are provided with private areas where they can talk with health professionals and no one can overhear, and that hospital staff treat the family members or friends who accompany patients in a courteous and friendly way. PMID:29161947
Transition in the waiting-time distribution of price-change events in a global socioeconomic system
NASA Astrophysics Data System (ADS)
Zhao, Guannan; McDonald, Mark; Fenn, Dan; Williams, Stacy; Johnson, Nicholas; Johnson, Neil F.
2013-12-01
The goal of developing a firmer theoretical understanding of inhomogeneous temporal processes-in particular, the waiting times in some collective dynamical system-is attracting significant interest among physicists. Quantifying the deviations between the waiting-time distribution and the distribution generated by a random process may help unravel the feedback mechanisms that drive the underlying dynamics. We analyze the waiting-time distributions of high-frequency foreign exchange data for the best executable bid-ask prices across all major currencies. We find that the lognormal distribution yields a good overall fit for the waiting-time distribution between currency rate changes if both short and long waiting times are included. If we restrict our study to long waiting times, each currency pair’s distribution is consistent with a power-law tail with exponent near to 3.5. However, for short waiting times, the overall distribution resembles one generated by an archetypal complex systems model in which boundedly rational agents compete for limited resources. Our findings suggest that a gradual transition arises in trading behavior between a fast regime in which traders act in a boundedly rational way and a slower one in which traders’ decisions are driven by generic feedback mechanisms across multiple timescales and hence produce similar power-law tails irrespective of currency type.
Sun, Jing; Lin, Qian; Zhao, Pengyu; Zhang, Qiongyao; Xu, Kai; Chen, Huiying; Hu, Cecile Jia; Stuntz, Mark; Li, Hong; Liu, Yuanli
2017-08-22
It is globally agreed that a well-designed health system deliver timely and convenient access to health services for all patients. Many interventions aiming to reduce waiting times have been implemented in Chinese public tertiary hospitals to improve patients' satisfaction. However, few were well-documented, and the effects were rarely measured with robust methods. We conducted a longitudinal study of the length of waiting times in a public tertiary hospital in Southern China which developed comprehensive data collection systems. Around an average of 60,000 outpatients and 70,000 prescribed outpatients per month were targeted for the study during Oct 2014-February 2017. We analyzed longitudinal time series data using a segmented linear regression model to assess changes in levels and trends of waiting times before and after the introduction of waiting time reduction interventions. Pearson correlation analysis was conducted to indicate the strength of association between waiting times and patient satisfactions. The statistical significance level was set at 0.05. The monthly average length of waiting time decreased 3.49 min (P = 0.003) for consultations and 8.70 min (P = 0.02) for filling prescriptions in the corresponding month when respective interventions were introduced. The trend shifted from baseline slight increasing to afterwards significant decreasing for filling prescriptions (P =0.003). There was a significant negative correlation between waiting time of filling prescriptions and outpatient satisfaction towards pharmacy services (r = -0.71, P = 0.004). The interventions aimed at reducing waiting time and raising patient satisfaction in Fujian Provincial Hospital are effective. A long-lasting reduction effect on waiting time for filling prescriptions was observed because of carefully designed continuous efforts, rather than a one-time campaign, and with appropriate incentives implemented by a taskforce authorized by the hospital managers. This case provides a model of carrying out continuous quality improvement and optimizing management process with the support of relevant evidence.
Wait times for gastroenterology consultation in Canada: The patients’ perspective
Paterson, WG; Barkun, AN; Hopman, WM; Leddin, DJ; Paré, P; Petrunia, DM; Sewitch, MJ; Switzer, C; van Zanten, S Veldhuyzen
2010-01-01
Long wait times for health care have become a significant issue in Canada. As part of the Canadian Association of Gastroenterology’s Human Resource initiative, a questionnaire was developed to survey patients regarding wait times for initial gastroenterology consultation and its impact. A total of 916 patients in six cities from across Canada completed the questionnaire at the time of initial consultation. Self-reported wait times varied widely, with 26.8% of respondents reporting waiting less than two weeks, 52.4% less than one month, 77.1% less than three months, 12.5% reported waiting longer than six months and 3.6% longer than one year. One-third of patients believed their wait time was too long, with 9% rating their wait time as ‘far too long’; 96.4% believed that maximal wait time should be less than three months, 78.9% believed it should be less than one month and 40.3% believed it should be less than two weeks. Of those working or attending school, 22.6% reported missing at least one day of work or school because of their symptoms in the month before their appointment, and 9.0% reported missing five or more days in the preceding month. A total of 20.2% of respondents reported being very worried about having a serious disease (ie, scored 6 or higher on 7-point Likert scale), and 17.6% and 14.8%, respectively, reported that their symptoms caused major impairment of social functioning and with the activities of daily living. These data suggest that a significant proportion of Canadians with digestive problems are not satisfied with their wait time for gastroenterology consultation. Furthermore, while awaiting consultation, many patients experience an impaired quality of life because of their gastrointestinal symptoms. PMID:20186353
Waiting time distribution revealing the internal spin dynamics in a double quantum dot
NASA Astrophysics Data System (ADS)
Ptaszyński, Krzysztof
2017-07-01
Waiting time distribution and the zero-frequency full counting statistics of unidirectional electron transport through a double quantum dot molecule attached to spin-polarized leads are analyzed using the quantum master equation. The waiting time distribution exhibits a nontrivial dependence on the value of the exchange coupling between the dots and the gradient of the applied magnetic field, which reveals the oscillations between the spin states of the molecule. The zero-frequency full counting statistics, on the other hand, is independent of the aforementioned quantities, thus giving no insight into the internal dynamics. The fact that the waiting time distribution and the zero-frequency full counting statistics give a nonequivalent information is associated with two factors. Firstly, it can be explained by the sensitivity to different timescales of the dynamics of the system. Secondly, it is associated with the presence of the correlation between subsequent waiting times, which makes the renewal theory, relating the full counting statistics and the waiting time distribution, no longer applicable. The study highlights the particular usefulness of the waiting time distribution for the analysis of the internal dynamics of mesoscopic systems.
Enhancing outpatient clinics management software by reducing patients' waiting time.
Almomani, Iman; AlSarheed, Ahlam
The Kingdom of Saudi Arabia (KSA) gives great attention to improving the quality of services provided by health care sectors including outpatient clinics. One of the main drawbacks in outpatient clinics is long waiting time for patients-which affects the level of patient satisfaction and the quality of services. This article addresses this problem by studying the Outpatient Management Software (OMS) and proposing solutions to reduce waiting times. Many hospitals around the world apply solutions to overcome the problem of long waiting times in outpatient clinics such as hospitals in the USA, China, Sri Lanka, and Taiwan. These clinics have succeeded in reducing wait times by 15%, 78%, 60% and 50%, respectively. Such solutions depend mainly on adding more human resources or changing some business or management policies. The solutions presented in this article reduce waiting times by enhancing the software used to manage outpatient clinics services. Both quantitative and qualitative methods have been used to understand current OMS and examine level of patient's satisfaction. Five main problems that may cause high or unmeasured waiting time have been identified: appointment type, ticket numbering, doctor late arrival, early arriving patient and patients' distribution list. These problems have been mapped to the corresponding OMS components. Solutions to the above problems have been introduced and evaluated analytically or by simulation experiments. Evaluation of the results shows a reduction in patient waiting time. When late doctor arrival issues are solved, this can reduce the clinic service time by up to 20%. However, solutions for early arriving patients reduces 53.3% of vital time, 20% of the clinic time and overall 30.3% of the total waiting time. Finally, well patient-distribution lists make improvements by 54.2%. Improvements introduced to the patients' waiting time will consequently affect patients' satisfaction and improve the quality of health care services. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.
The 2012 SAGE wait times program: Survey of Access to GastroEnterology in Canada
Leddin, Desmond; Armstrong, David; Borgaonkar, Mark; Bridges, Ronald J; Fallone, Carlo A; Telford, Jennifer J; Chen, Ying; Colacino, Palma; Sinclair, Paul
2013-01-01
BACKGROUND: Periodically surveying wait times for specialist health services in Canada captures current data and enables comparisons with previous surveys to identify changes over time. METHODS: During one week in April 2012, Canadian gastroenterologists were asked to complete a questionnaire (online or by fax) recording demographics, reason for referral, and dates of referral and specialist visits for at least 10 consecutive new patients (five consultations and five procedures) who had not been seen previously for the same indication. Wait times were determined for 18 indications and compared with those from similar surveys conducted in 2008 and 2005. RESULTS: Data regarding adult patients were provided by 173 gastroenterologists for 1374 consultations, 540 procedures and 293 same-day consultations and procedures. Nationally, the median wait times were 92 days (95% CI 85 days to 100 days) from referral to consultation, 55 days (95% CI 50 days to 61 days) from consultation to procedure and 155 days (95% CI 142 days to 175 days) (total) from referral to procedure. Overall, wait times were longer in 2012 than in 2005 (P<0.05); the wait time to same-day consultation and procedure was shorter in 2012 than in 2008 (78 days versus 101 days; P<0.05), but continued to be longer than in 2005 (P<0.05). The total wait time remained longest for screening colonoscopy, increasing from 201 days in 2008 to 279 days in 2012 (P<0.05). DISCUSSION: Wait times for gastroenterology services continue to exceed recommended targets, remain unchanged since 2008 and exceed wait times reported in 2005. PMID:23472243
Survey of Access to GastroEnterology in Canada: The SAGE wait times program
Leddin, Desmond; Bridges, Ronald J; Morgan, David G; Fallone, Carlo; Render, Craig; Plourde, Victor; Gray, Jim; Switzer, Connie; McHattie, Jim; Singh, Harminder; Walli, Eric; Murray, Iain; Nestel, Anthony; Sinclair, Paul; Chen, Ying; Irvine, E Jan
2010-01-01
BACKGROUND: Assessment of current wait times for specialist health services in Canada is a key method that can assist government and health care providers to plan wisely for future health needs. These data are not readily available. A method to capture wait time data at the time of consultation or procedure has been developed, which should be applicable to other specialist groups and also allows for assessment of wait time trends over intervals of years. METHODS: In November 2008, gastroenterologists across Canada were asked to complete a questionnaire (online or by fax) that included personal demographics and data from one week on at least five consecutive new consultations and five consecutive procedure patients who had not previously undergone a procedure for the same indication. Wait times were collected for 18 primary indications and results were then compared with similar survey data collected in 2005. RESULTS: The longest wait times observed were for screening colonoscopy (201 days) and surveillance of previous colon cancer or polyps (272 days). The shortest wait times were for cancer-likely based on imaging or physical examination (82 days), severe or rapidly progressing dysphagia or odynophagia (83 days), documented iron-deficiency anemia (90 days) and dyspepsia with alarm symptoms (99 days). Compared with 2005 data, total wait times in 2008 were lengthened overall (127 days versus 155 days; P<0.05) and for most of the seven individual indications that permitted data comparison. CONCLUSION: Median wait times for gastroenterology services continue to exceed consensus conference recommended targets and have significantly worsened since 2005. PMID:20186352
Stochastic nature of series of waiting times.
Anvari, Mehrnaz; Aghamohammadi, Cina; Dashti-Naserabadi, H; Salehi, E; Behjat, E; Qorbani, M; Nezhad, M Khazaei; Zirak, M; Hadjihosseini, Ali; Peinke, Joachim; Tabar, M Reza Rahimi
2013-06-01
Although fluctuations in the waiting time series have been studied for a long time, some important issues such as its long-range memory and its stochastic features in the presence of nonstationarity have so far remained unstudied. Here we find that the "waiting times" series for a given increment level have long-range correlations with Hurst exponents belonging to the interval 1/2
Impact of Appointment Waiting Time on Attendance Rates at a Clinical Cancer Genetics Service.
Shaw, Tarryn; Metras, Julie; Ting, Zoe Ang Li; Courtney, Eliza; Li, Shao-Tzu; Ngeow, Joanne
2018-05-24
The increase in demand for clinical cancer genetics services has impacted the ability to provide services timeously. Given limited resources, this often results in extended appointment waiting times. Over the last 3 years, the Cancer Genetics Service at the National Cancer Centre Singapore has continued to experience a steady increase in demand for its service. Nevertheless, significant no-show rates have been reported. This study sought to determine whether an association exists between appointment waiting times and attendance rates. Data was gathered for all participants meeting inclusion criteria. Attendance rates and appointment waiting times were calculated. The relationship between mean waiting times for those who did and did not attend their scheduled appointments was evaluated using Welch's t test and linear regression model. The results showed a significant difference in mean appointment waiting times between patients who did and did not attend (32.66 versus 43.50 days respectively; p < 0.0001). Furthermore, patients who waited for longer than 37 days were significantly less likely to attend. No-show rates increased as the waiting time increased, at a rate of 19.60% per 20 days and 21.40% per 30 days. In conclusion, appointment waiting time is a significant predictor for patient attendance. Strategies to ensure patients receive an appointment within the necessary timeframe at the desired setting are important to ensure that individuals at increased cancer risk attend their appointments in order to manage their cancer risks effectively.
Shorter Perceived Outpatient MRI Wait Times Associated With Higher Patient Satisfaction.
Holbrook, Anna; Glenn, Harold; Mahmood, Rabia; Cai, Qingpo; Kang, Jian; Duszak, Richard
2016-05-01
The aim of this study was to assess differences in perceived versus actual wait times among patients undergoing outpatient MRI examinations and to correlate those times with patient satisfaction. Over 15 weeks, 190 patients presenting for outpatient MR in a radiology department in which "patient experience" is one of the stated strategic priorities were asked to (1) estimate their wait times for various stages in the imaging process and (2) state their satisfaction with their imaging experience. Perceived times were compared with actual electronic time stamps. Perceived and actual times were compared and correlated with standardized satisfaction scores using Kendall τ correlation. The mean actual wait time between patient arrival and examination start was 53.4 ± 33.8 min, whereas patients perceived a mean wait time of 27.8 ± 23.1 min, a statistically significant underestimation of 25.6 min (P < .001). Both shorter actual and perceived wait times at all points during patient encounters were correlated with higher satisfaction scores (P < .001). Patients undergoing outpatient MR examinations in an environment designed to optimize patient experience underestimated wait times at all points during their encounters. Shorter perceived and actual wait times were both correlated with higher satisfaction scores. As satisfaction surveys play a larger role in an environment of metric transparency and value-based payments, better understanding of such factors will be increasingly important. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.
Study on transfer optimization of urban rail transit and conventional public transport
NASA Astrophysics Data System (ADS)
Wang, Jie; Sun, Quan Xin; Mao, Bao Hua
2018-04-01
This paper mainly studies the time optimization of feeder connection between rail transit and conventional bus in a shopping center. In order to achieve the goal of connecting rail transportation effectively and optimizing the convergence between the two transportations, the things had to be done are optimizing the departure intervals, shorting the passenger transfer time and improving the service level of public transit. Based on the goal that has the minimum of total waiting time of passengers and the number of start of classes, establish the optimizing model of bus connecting of departure time. This model has some constrains such as transfer time, load factor, and the convergence of public transportation grid spacing. It solves the problems by using genetic algorithms.
NASA Astrophysics Data System (ADS)
Hino, Hisato; Hoshino, Satoshi; Fujisawa, Tomoharu; Maruyama, Shigehisa; Ota, Jun
Currently, container ships move cargo with minimal participation from external trucks. However, there is slack time between the departure of container ships and the completion of cargo handling by container ships without the participation of external trucks; therefore, external trucks can be used to move cargo without delaying the departure time. In this paper, we propose a solution involving the control algorithms of transfer cranes (TCs) because the efficiency of yard operations depends largely on the productivity of TCs. TCs work according to heuristic rules using the forecasted arrival times of internal and external trucks. Simulation results show that the proposed method can reduce the waiting time of external trucks and meet the departure time of container ships.
Llewellyn-Thomas, H A; Arshinoff, R; Bell, M; Williams, J I; Naylor, C D
1998-02-01
We assessed patients on the waiting lists of a purposive sample of orthopaedic surgeons in Ontario, Canada, to determine patients' attitudes towards time waiting for hip or knee replacement. We focused on 148 patients who did not have a definite operative date, obtaining complete information on 124 (84%). Symptom severity was assessed with the Western Ontario/McMaster Osteoarthritis Index and a disease-specific standard gamble was used to elicit patients' overall utility for their arthritic state. Next, in a trade-off task, patients considered a hypothetical choice between a 1-month wait for a surgeon who could provide a 2% risk of post-operative mortality, or a 6-month wait for joint replacement with a 1% risk of post-operative mortality. Waiting times were then shifted systematically until the patient abandoned his/her initial choice, generating a conditional maximal acceptable wait time. Patients were divided in their attitudes, with 57% initially choosing a 6-month wait with a 1% mortality risk. The overall distribution of conditional maximum acceptable wait time scores ranged from 1 to 26 months, with a median of 7 months. Utility values were independently but weakly associated with patients' tolerance of waiting times (adjusted R-square = 0.059, P = 0.004). After splitting the sample along the median into subgroups with a relatively 'low' and 'high' tolerance for waiting, the subgroup with the apparently lower tolerance for waiting reported lower utility scores (z = 2.951; P = 0.004) and shorter times since their surgeon first advised them of the need for surgery (z = 3.014; P = 0.003). These results suggest that, in the establishment and monitoring of a queue management system for quality-of-life-enhancing surgery, patients' own perceptions of their overall symptomatic burden and ability to tolerate delayed relief should be considered along with information derived from clinical judgements and pre-weighted health status instruments.
The effect of in-office waiting time on physician visit frequency among working-age adults.
Tak, Hyo Jung; Hougham, Gavin W; Ruhnke, Atsuko; Ruhnke, Gregory W
2014-10-01
Disparities in unmet health care demand resulting from socioeconomic, racial, and financial factors have received a great deal of attention in the United States. However, out-of-pocket costs alone do not fully reflect the total opportunity cost that patients must consider as they seek medical attention. While there is an extensive literature on the price elasticity of demand for health care, empirical evidence regarding the effect of waiting time on utilization is sparse. Using the nationally representative 2003 Community Tracking Study Household Survey, the most recent iteration containing respondents' physician office visit frequency and estimated in-office waiting time in the United States (N = 23,484), we investigated the association between waiting time and calculated time cost with the number of physician visits among a sample of working-age adults. To avoid the bias that literature suggests would result from excluding respondents with zero physician visits, we imputed waiting time for the essential inclusion of such individuals. On average, respondents visited physician offices 3.55 times, during which time they waited 28.7 min. The estimates from a negative binomial model indicated that a doubling of waiting time was associated with a 7.7 percent decrease (p-value < 0.001) in physician visit frequency. For women and unemployed respondents, who visited physicians more frequently, the decrease was even larger, suggesting a stronger response to greater waiting times. We believe this finding reflects the discretionary nature of incremental visits in these groups, and a consequent lower perceived marginal benefit of additional visits. The results suggest that in-office waiting time may have a substantial influence on patients' propensity to seek medical attention. Although there is a belief that expansions in health insurance coverage increase health care utilization by reducing financial barriers to access, our results suggest that unintended consequences may arise if in-office waiting time increases. Copyright © 2014 Elsevier Ltd. All rights reserved.
Indication criteria for cataract extraction and gender differences in waiting time.
Smirthwaite, Goldina; Lundström, Mats; Albrecht, Susanne; Swahnberg, Katarina
2014-08-01
The purpose of this study was to investigate national indication criteria tool for cataract extraction (NIKE), a clinical tool for establishing levels of indications for cataract surgery, in relation to gender differences in waiting times for cataract extraction (CE). Data were collected by The Swedish National Cataract Register (NCR). Eye clinics report to NCR voluntarily and on regular basis (98% coverage). Comparisons regarding gender difference in waiting times were performed between NIKE-categorized and non-NIKE-categorized patients, as well as between different indication groups within the NIKE-system. All calculations were performed in spss version 20. Multivariate analyses were carried out using logistic regression, and single variable analyses were carried out by Student's t-test or chi square as appropriate. Gender, age, visual acuity and NIKE-categorization were associated with waiting time. Female patients had a longer waiting time to CE than male, both within and outside the NIKE-system. Gender difference in waiting time was somewhat larger among patients who had not been categorized by NIKE. In the non-NIKE-categorized group, women waited 0.20 months longer than men. In the group which was NIKE-categorized, women waited 0.18 months longer than men. It is reasonable to assume that prioritizing patients by means of NIKE helps to reduce the gender differences in waiting time. Gender differences in waiting time have decreased as NIKE was introduced and there may be a variety of explanations for this. However, with the chosen study design, we could not distinguish between effects related to NIKE and those due to other factors which occurred during the study period. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
Song, Huan; Fang, Fang; Valdimarsdóttir, Unnur; Lu, Donghao; Andersson, Therese M-L; Hultman, Christina; Ye, Weimin; Lundell, Lars; Johansson, Jan; Nilsson, Magnus; Lindblad, Mats
2017-01-03
Except for overall survival, whether or not waiting time for treatment could influences other domains of cancer patients' overall well-being is to a large extent unknown. Therefore, we performed this study to determine the effect of waiting time for cancer treatment on the mental health of patients with esophageal or gastric cancer. Based on the Swedish National Quality Register for Esophageal and Gastric Cancers (NREV), we followed 7,080 patients diagnosed 2006-2012 from the time of treatment decision. Waiting time for treatment was defined as the interval between diagnosis and treatment decision, and was classified into quartiles. Mental disorders were identified by either clinical diagnosis through hospital visit or prescription of psychiatric medications. For patients without any mental disorder before treatment, the association between waiting time and subsequent onset of mental disorders was assessed by hazard ratios (HRs) with 95% confidence interval (CI), derived from multivariable-adjusted Cox model. For patients with a preexisting mental disorder, we compared the rate of psychiatric care by different waiting times, allowing for repeated events. Among 4,120 patients without any preexisting mental disorder, lower risk of new onset mental disorders was noted for patients with longer waiting times, i.e. 18-29 days (HR 0.86; 95% CI 0.74-1.00) and 30-60 days (HR 0.79; 95% CI 0.67-0.93) as compared with 9-17 days. Among 2,312 patients with preexisting mental disorders, longer waiting time was associated with more frequent psychiatric hospital care during the first year after treatment (37.5% higher rate per quartile increase in waiting time; p for trend = 0.0002). However, no such association was observed beyond one year nor for the prescription of psychiatric medications. These data suggest that waiting time to treatment for esophageal or gastric cancer may have different mental health consequences for patients depending on their past psychiatric vulnerabilities. Our study sheds further light on the complexity of waiting time management, and calls for a comprehensive strategy that takes into account different domains of patient well-being in addition to the overall survival.
Stochastic nature of series of waiting times
NASA Astrophysics Data System (ADS)
Anvari, Mehrnaz; Aghamohammadi, Cina; Dashti-Naserabadi, H.; Salehi, E.; Behjat, E.; Qorbani, M.; Khazaei Nezhad, M.; Zirak, M.; Hadjihosseini, Ali; Peinke, Joachim; Tabar, M. Reza Rahimi
2013-06-01
Although fluctuations in the waiting time series have been studied for a long time, some important issues such as its long-range memory and its stochastic features in the presence of nonstationarity have so far remained unstudied. Here we find that the “waiting times” series for a given increment level have long-range correlations with Hurst exponents belonging to the interval 1/2
RECONCILIATION OF WAITING TIME STATISTICS OF SOLAR FLARES OBSERVED IN HARD X-RAYS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aschwanden, Markus J.; McTiernan, James M., E-mail: aschwanden@lmsal.co, E-mail: jimm@ssl.berkeley.ed
2010-07-10
We study the waiting time distributions of solar flares observed in hard X-rays with ISEE-3/ICE, HXRBS/SMM, WATCH/GRANAT, BATSE/CGRO, and RHESSI. Although discordant results and interpretations have been published earlier, based on relatively small ranges (<2 decades) of waiting times, we find that all observed distributions, spanning over 6 decades of waiting times ({Delta}t {approx} 10{sup -3}-10{sup 3} hr), can be reconciled with a single distribution function, N({Delta}t) {proportional_to} {lambda}{sub 0}(1 + {lambda}{sub 0{Delta}}t){sup -2}, which has a power-law slope of p {approx} 2.0 at large waiting times ({Delta}t {approx} 1-1000 hr) and flattens out at short waiting times {Delta}t {approx}
Baliski, Christopher; McGahan, Colleen E; Liberto, Caitlyn M; Broughton, Sandra; Ellard, Susan; Taylor, Marianne; Bates, Janet; Lai, Anky
2014-05-01
The wait times for breast cancer care in our region do not meet acceptable benchmarks. We implemented the Interior Breast Rapid Access Investigation and Diagnosis (IB-RAPID) nurse navigation program to address this issue. The IB-RAPID prospective database was reviewed for patients entering the program between April 1, 2011 and April 30, 2012 (2011/2012 cohort), and was compared with patients from the same area in 2010. The main end point was the time between the 1st diagnostic imaging test and the surgery. Multiple linear regression was performed to investigate factors influencing the wait times. The wait times decreased with the introduction of IB-RAPID (59 vs 48 days; median). Stage of disease, total number of biopsies, and magnetic resonance imaging (MRI) use influenced wait times. MRI significantly delayed surgical intervention in both groups with those not having an MRI having a shorter wait time to surgery (68.5 vs 57.6 days; mean) in 2011/2012. The implementation of nurse navigation for patients with breast cancer appears to be effective at reducing the wait times for surgical treatment. Copyright © 2014 Elsevier Inc. All rights reserved.
How to report and monitor the performance of waiting list management.
Torkki, Markus; Linna, Miika; Seitsalo, Seppo; Paavolainen, Pekka
2002-01-01
Potential problems concerning waiting list management are often monitored using mean waiting times based on empirical samples. However, the appropriateness of mean waiting time as an indicator of access can be questioned if a waiting list is not managed well, e.g., if the queue discipline is violated. This study was performed to find out about the queue discipline in waiting lists for elective surgery to reveal potential discrepancies in waiting list management. There were 1,774 waiting list patients for hallux valgus or varicose vein surgery or sterilization. The waiting time distributions of patients receiving surgery and of patients still waiting for an operation are presented in column charts. The charts are compared with two model charts. One model chart presents a high queue discipline (first in-first out) and another a poor queue discipline (random) queue. There were significant differences in waiting list management across hospitals and patient categories. Examples of a poor queue discipline were found in queues for hallux valgus and varicose vein operations. A routine waiting list reporting should be used to guarantee the quality of waiting list management and to pinpoint potential problems in access. It is important to monitor not only the number of patients in the waiting list but also the queue discipline and the balance between demand and supply of surgical services. The purpose for this type of reporting is to ensure that the priority setting made at health policy level also works in practise.
Automatic calibration system for analog instruments based on DSP and CCD sensor
NASA Astrophysics Data System (ADS)
Lan, Jinhui; Wei, Xiangqin; Bai, Zhenlong
2008-12-01
Currently, the calibration work of analog measurement instruments is mainly completed by manual and there are many problems waiting for being solved. In this paper, an automatic calibration system (ACS) based on Digital Signal Processor (DSP) and Charge Coupled Device (CCD) sensor is developed and a real-time calibration algorithm is presented. In the ACS, TI DM643 DSP processes the data received by CCD sensor and the outcome is displayed on Liquid Crystal Display (LCD) screen. For the algorithm, pointer region is firstly extracted for improving calibration speed. And then a math model of the pointer is built to thin the pointer and determine the instrument's reading. Through numbers of experiments, the time of once reading is no more than 20 milliseconds while it needs several seconds if it is done manually. At the same time, the error of the instrument's reading satisfies the request of the instruments. It is proven that the automatic calibration system can effectively accomplish the calibration work of the analog measurement instruments.
Becker, Franklin; Douglass, Stephanie
2008-01-01
This study examined the relationship between the attractiveness of the physical environment of healthcare facilities and patient perceptions of quality, service, and waiting time through systematic observations and patient satisfaction surveys at 7 outpatient practices at Weill Cornell Medical Center. Findings indicate positive correlations between more attractive environments and higher levels of perceived quality, satisfaction, staff interaction, and reduction of patient anxiety. The comparison of actual observed time and patients' perception of time showed that patients tend to overestimate shorter waiting times and underestimate longer waiting times in both the waiting area and the examination room. Further examinations of the way outpatient-practice environments impact patient and staff perceptions and how those perceptions impact behavior and medical outcomes are suggested.
Public views on a wait time management initiative: a matter of communication
2010-01-01
Background Many countries have tried to reduce waiting times for health care through formal wait time reduction strategies. Our paper describes views of members of the public about a wait time management initiative - the Ontario Wait Time Strategy (OWTS) (Canada). Scholars and governmental reports have advocated for increased public involvement in wait time management. We provide empirically derived recommendations for public engagement in a wait time management initiative. Methods Two qualitative studies: 1) an analysis of all emails sent by the public to the (OWTS) email address; and 2) in-depth interviews with members of the Ontario public. Results Email correspondents and interview participants supported the intent of the OWTS. However they wanted more information about the Strategy and its actions. Interview participants did not feel they were sufficiently made aware of the Strategy and email correspondents requested additional information beyond what was offered on the Strategy's website. Moreover, the email correspondents believed that some of the information that was provided on the Strategy's website and through the media was inaccurate, misleading, and even dishonest. Interview participants strongly supported public involvement in the OWTS priority setting. Conclusions Findings suggest the public wanted increased communication from and with the OWTS. Effective communication can facilitate successful public engagement, and in turn fair and legitimate priority setting. Based on the study's findings we developed concrete recommendations for improving public involvement in wait time management. PMID:20687952
Public views on a wait time management initiative: a matter of communication.
Bruni, Rebecca A; Laupacis, Andreas; Levinson, Wendy; Martin, Douglas K
2010-08-05
Many countries have tried to reduce waiting times for health care through formal wait time reduction strategies. Our paper describes views of members of the public about a wait time management initiative--the Ontario Wait Time Strategy (OWTS) (Canada). Scholars and governmental reports have advocated for increased public involvement in wait time management. We provide empirically derived recommendations for public engagement in a wait time management initiative. Two qualitative studies: 1) an analysis of all emails sent by the public to the (OWTS) email address; and 2) in-depth interviews with members of the Ontario public. Email correspondents and interview participants supported the intent of the OWTS. However they wanted more information about the Strategy and its actions. Interview participants did not feel they were sufficiently made aware of the Strategy and email correspondents requested additional information beyond what was offered on the Strategy's website. Moreover, the email correspondents believed that some of the information that was provided on the Strategy's website and through the media was inaccurate, misleading, and even dishonest. Interview participants strongly supported public involvement in the OWTS priority setting. Findings suggest the public wanted increased communication from and with the OWTS. Effective communication can facilitate successful public engagement, and in turn fair and legitimate priority setting. Based on the study's findings we developed concrete recommendations for improving public involvement in wait time management.
Emergency department waiting times: Do the raw data tell the whole story?
Green, Janette; Dawber, James; Masso, Malcolm; Eagar, Kathy
2014-02-01
To determine whether there are real differences in emergency department (ED) performance between Australian states and territories. Cross-sectional analysis of 2009-10 attendances at an ED contributing to the Australian non-admitted patient ED care database. The main outcome measure was difference in waiting time across triage categories. There were more than 5.8 million ED attendances. Raw ED waiting times varied by a range of factors including jurisdiction, triage category, geographic location and hospital peer group. All variables were significant in a model designed to test the effect of jurisdiction on ED waiting times, including triage category, hospital peer group, patient socioeconomic status and patient remoteness. When the interaction between triage category and jurisdiction entered the model, it was found to have a significant effect on ED waiting times (P<0.001) and triage was also significant (P<0.001). Jurisdiction was no longer statistically significant (P=0.248 using all triage categories and 0.063 using only Australian Triage Scale 2 and 3). Although the Council of Australian Governments has adopted raw measures for its key ED performance indicators, raw waiting time statistics are misleading. There are no consistent differences in ED waiting times between states and territories after other factors are accounted for. WHAT IS KNOWN ABOUT THE TOPIC? The length of time patients wait to be treated after presenting at an ED is routinely used to measure ED performance. In national health agreements with the federal government, each state and territory in Australia is expected to meet waiting time performance targets for the five ED triage categories. The raw data indicate differences in performance between states and territories. WHAT DOES THIS PAPER ADD? Measuring ED performance using raw data gives misleading results. There are no consistent differences in ED waiting times between the states and territories after other factors are taken into account. WHAT ARE THE IMPLICATIONS FOR PRACTITIONERS? Judgements regarding differences in performance across states and territories for triage waiting times need to take into account the mix of patients and the mix of hospitals.
CUDA-based high-performance computing of the S-BPF algorithm with no-waiting pipelining
NASA Astrophysics Data System (ADS)
Deng, Lin; Yan, Bin; Chang, Qingmei; Han, Yu; Zhang, Xiang; Xi, Xiaoqi; Li, Lei
2015-10-01
The backprojection-filtration (BPF) algorithm has become a good solution for local reconstruction in cone-beam computed tomography (CBCT). However, the reconstruction speed of BPF is a severe limitation for clinical applications. The selective-backprojection filtration (S-BPF) algorithm is developed to improve the parallel performance of BPF by selective backprojection. Furthermore, the general-purpose graphics processing unit (GP-GPU) is a popular tool for accelerating the reconstruction. Much work has been performed aiming for the optimization of the cone-beam back-projection. As the cone-beam back-projection process becomes faster, the data transportation holds a much bigger time proportion in the reconstruction than before. This paper focuses on minimizing the total time in the reconstruction with the S-BPF algorithm by hiding the data transportation among hard disk, CPU and GPU. And based on the analysis of the S-BPF algorithm, some strategies are implemented: (1) the asynchronous calls are used to overlap the implemention of CPU and GPU, (2) an innovative strategy is applied to obtain the DBP image to hide the transport time effectively, (3) two streams for data transportation and calculation are synchronized by the cudaEvent in the inverse of finite Hilbert transform on GPU. Our main contribution is a smart reconstruction of the S-BPF algorithm with GPU's continuous calculation and no data transportation time cost. a 5123 volume is reconstructed in less than 0.7 second on a single Tesla-based K20 GPU from 182 views projection with 5122 pixel per projection. The time cost of our implementation is about a half of that without the overlap behavior.
Delays in Prior Living Kidney Donors Receiving Priority on the Transplant Waiting List
Klassen, David K.; Kucheryavaya, Anna Y.; Stewart, Darren E.
2016-01-01
Background and objectives Prior living donors (PLDs) receive very high priority on the Organ Procurement and Transplantation Network (OPTN) kidney waiting list. Program delays in adding PLDs to the waiting list, setting their status to active, and submitting requests for PLD priority can affect timely access to transplantation. Design, setting, participants, & measurements We used the OPTN and the Centers for Medicare and Medicaid Services data to examine timing of (1) listing relative to start of dialysis, (2) activation on the waiting list, and (3) requests for PLD priority relative to listing date. There were 210 PLDs (221 registrations) added to the OPTN kidney waiting list between January 1, 2010 and July 31, 2015. Results As of September 4, 2015, 167 of the 210 PLDs received deceased donor transplants, six received living donor transplants, two died, five were too sick to transplant, and 29 were still waiting. Median waiting time to deceased donor transplant for PLDs was 98 days. Only 40.7% of 221 PLD registrations (n=90) were listed before they began dialysis; 68.3% were in inactive status for <90 days, 17.6% were in inactive status for 90–365 days, 8.6% were in inactive status for 1–2 years, and 5.4% were in inactive status for >2 years. Median time of PLDs waiting in active status before receiving PLD priority was 2 days (range =0–1450); 67.4% of PLDs received PLD priority within 7 days after activation, but 15.4% waited 8–30 days, 8.1% waited 1–3 months, 4.1% waited 3–12 months, and 5.0% waited >1 year in active status for PLD priority. After receiving priority, most were transplanted quickly. Median time in active status with PLD priority before deceased donor transplant was 23 days. Conclusions Fewer than one half of listed PLDs were listed before starting dialysis. Most listed PLDs are immediately set to active status and receive PLD priority quickly, but a substantial number spends time in active status without PLD priority or a large amount of time in inactive status, which affects access to timely transplants. PMID:27591296
NASA Astrophysics Data System (ADS)
Nordin, Noraimi Azlin Mohd; Omar, Mohd; Sharif, S. Sarifah Radiah
2017-04-01
Companies are looking forward to improve their productivity within their warehouse operations and distribution centres. In a typical warehouse operation, order picking contributes more than half percentage of the operating costs. Order picking is a benchmark in measuring the performance and productivity improvement of any warehouse management. Solving order picking problem is crucial in reducing response time and waiting time of a customer in receiving his demands. To reduce the response time, proper routing for picking orders is vital. Moreover, in production line, it is vital to always make sure the supplies arrive on time. Hence, a sample routing network will be applied on EP Manufacturing Berhad (EPMB) as a case study. The Dijkstra's algorithm and Dynamic Programming method are applied to find the shortest distance for an order picker in order picking. The results show that the Dynamic programming method is a simple yet competent approach in finding the shortest distance to pick an order that is applicable in a warehouse within a short time period.
A Sarsa(λ)-Based Control Model for Real-Time Traffic Light Coordination
Zhu, Fei; Liu, Quan; Fu, Yuchen; Huang, Wei
2014-01-01
Traffic problems often occur due to the traffic demands by the outnumbered vehicles on road. Maximizing traffic flow and minimizing the average waiting time are the goals of intelligent traffic control. Each junction wants to get larger traffic flow. During the course, junctions form a policy of coordination as well as constraints for adjacent junctions to maximize their own interests. A good traffic signal timing policy is helpful to solve the problem. However, as there are so many factors that can affect the traffic control model, it is difficult to find the optimal solution. The disability of traffic light controllers to learn from past experiences caused them to be unable to adaptively fit dynamic changes of traffic flow. Considering dynamic characteristics of the actual traffic environment, reinforcement learning algorithm based traffic control approach can be applied to get optimal scheduling policy. The proposed Sarsa(λ)-based real-time traffic control optimization model can maintain the traffic signal timing policy more effectively. The Sarsa(λ)-based model gains traffic cost of the vehicle, which considers delay time, the number of waiting vehicles, and the integrated saturation from its experiences to learn and determine the optimal actions. The experiment results show an inspiring improvement in traffic control, indicating the proposed model is capable of facilitating real-time dynamic traffic control. PMID:24592183
Optimal Server Scheduling to Maintain Constant Customer Waiting Times
1988-12-01
I I• I I I I I LCn CN OPTIMAL SERVER SCHEDUUNG TO MAINTAIN CONSTANT CUSTOMER WAITING TIMES THESIS Thomas J. Frey Captain UISAF AFIT/GOR/ENS/88D-7...hw bees appsewlf in ple rtan. cd = , ’ S 087 AFIT/GORMENS/8D-7 OPTIMAL SERVER SCHEDUUNG TO MAINTAIN~ CONSTANT CUSTOMER WAITING TIMES THESIS Thomas j...CONSTANT CUSTOMER WAITING TIMES THESIS Presented to the Faculty of the School of Engineering of the Air Force Institute of Technology Air University In
Effect of emergency physician burnout on patient waiting times.
De Stefano, Carla; Philippon, Anne-Laure; Krastinova, Evguenia; Hausfater, Pierre; Riou, Bruno; Adnet, Frederic; Freund, Yonathan
2018-04-01
Burnout is common in emergency physicians. This syndrome may negatively affect patient care and alter work productivity. We seek to assess whether burnout of emergency physicians impacts waiting times in the emergency department. Prospective study in an academic ED. All patients who visited the main ED for a 4-month period in 2016 were included. Target waiting times are assigned by triage nurse to patients on arrival depending on their severity. The primary endpoint was an exceeded target waiting time for ED patients. All emergency physicians were surveyed by a psychologist to assess their level of burnout using the Maslach Burnout Inventory. We defined the level of burnout of the day in the ED as the mean burnout level of the physicians working that day (8:30 to the 8:30 the next day). A logistic regression model was performed to assess whether burnout level of the day was independently associated with prolonged waiting times, along with previously reported predictors. Target waiting time was exceeded in 7524 patients (59%). Twenty-six emergency physicians were surveyed. Median burnout score was 35 [Interquartile (24-49)]. A burnout level of the day higher than 35 was independently associated with an exceeded target waiting time (adjusted odds ratio 1.54, 95% confidence interval 1.39-1.70), together with previously reported predictors (i.e., day of the week, time of the day, trauma, age and daily census). Burnout of emergency physicians was independently associated with a prolonged waiting time for patients visiting the ED.
Nakajima, Makoto; Inatomi, Yuichiro; Yonehara, Toshiro; Watanabe, Masaki; Ando, Yukio
2015-01-01
The aim of this study was to investigate whether stratifying patients according to the time period from admission to the start of regular working hours would help detect a weekend effect in acute stroke patients. Ischemic stroke patients admitted between October 2002 and March 2012 were analyzed. Working hours were defined as 9:00-17:00 on weekdays. Patients were divided into those admitted during working hours (no-wait group) and three other groups according to the time from admission to working hours: ≤24 h (short-wait group), 24-48 h (medium-wait group), and >48 h (long-wait group). The modified Rankin Scale score and mortality at three-months were compared among the groups. Of 5625 patients, 3323 (59%) were admitted outside working hours. The proportion of patients with an mRS score 0-1 at three-months showed a decreasing trend with the time period before working hours: 47% (no-wait group), 42% (short-wait group), 42% (medium-wait group), and 38% (long-wait group), respectively (P < 0·001). When the no-wait group was used as a reference, the odds ratio for modified Rankin Scale score 0-1 was 0·88 (95% confidence interval, 0·75-1·04) in the short-wait group, 0·86 (0·69-1·07) in the medium-wait group, and 0·67 (0·53-0·85) in the long-wait group after adjusting for sex, age, premorbid mRS score, previous morbidity, stroke severity, and vascular risk factors. Mortality at three-months was not different between the no-wait group and the other groups. A weekend effect might be evident if patients were stratified according to the time period from admission until working hours. © 2014 World Stroke Organization.
Improving generalized inverted index lock wait times
NASA Astrophysics Data System (ADS)
Borodin, A.; Mirvoda, S.; Porshnev, S.; Ponomareva, O.
2018-01-01
Concurrent operations on tree like data structures is a cornerstone of any database system. Concurrent operations intended for improving read\\write performance and usually implemented via some way of locking. Deadlock-free methods of concurrency control are known as tree locking protocols. These protocols provide basic operations(verbs) and algorithm (ways of operation invocations) for applying it to any tree-like data structure. These algorithms operate on data, managed by storage engine which are very different among RDBMS implementations. In this paper, we discuss tree locking protocol implementation for General inverted index (Gin) applied to multiversion concurrency control (MVCC) storage engine inside PostgreSQL RDBMS. After that we introduce improvements to locking protocol and provide usage statistics about evaluation of our improvement in very high load environment in one of the world’s largest IT company.
Goldstein, Benjamin A; Thomas, Laine; Zaroff, Jonathan G; Nguyen, John; Menza, Rebecca; Khush, Kiran K
2016-07-01
Over the past two decades, there have been increasingly long waiting times for heart transplantation. We studied the relationship between heart transplant waiting time and transplant failure (removal from the waitlist, pretransplant death, or death or graft failure within 1 year) to determine the risk that conservative donor heart acceptance practices confer in terms of increasing the risk of failure among patients awaiting transplantation. We studied a cohort of 28,283 adults registered on the United Network for Organ Sharing heart transplant waiting list between 2000 and 2010. We used Kaplan-Meier methods with inverse probability censoring weights to examine the risk of transplant failure accumulated over time spent on the waiting list (pretransplant). In addition, we used transplant candidate blood type as an instrumental variable to assess the risk of transplant failure associated with increased wait time. Our results show that those who wait longer for a transplant have greater odds of transplant failure. While on the waitlist, the greatest risk of failure is during the first 60 days. Doubling the amount of time on the waiting list was associated with a 10% (1.01, 1.20) increase in the odds of failure within 1 year after transplantation. Our findings suggest a relationship between time spent on the waiting list and transplant failure, thereby supporting research aimed at defining adequate donor heart quality and acceptance standards for heart transplantation.
Widdifield, Jessica; Bernatsky, Sasha; Thorne, J Carter; Bombardier, Claire; Jaakkimainen, R Liisa; Wing, Laura; Paterson, J Michael; Ivers, Noah; Butt, Debra; Lyddiatt, Anne; Hofstetter, Catherine; Ahluwalia, Vandana; Tu, Karen
2016-01-01
The Wait Time Alliance recently established wait time benchmarks for rheumatology consultations in Canada. Our aim was to quantify wait times to primary and rheumatology care for patients with rheumatic diseases. We identified patients from primary care practices in the Electronic Medical Record Administrative data Linked Database who had referrals to Ontario rheumatologists over the period 2000-2013. To assess the full care pathway, we identified dates of symptom onset, presentation in primary care and referral from electronic medical records. Dates of rheumatologist consultations were obtained by linking with physician service claims. We determined the duration of each phase of the care pathway (symptom onset to primary care encounter, primary care encounter to referral, and referral to rheumatologist consultation) and compared them with established benchmarks. Among 2430 referrals from 168 family physicians, 2015 patients (82.9%) were seen by 146 rheumatologists within 1 year of referral. Of the 2430 referrals, 2417 (99.5%) occurred between 2005 and 2013. The main reasons for referral were osteoarthritis (32.4%) and systemic inflammatory rheumatic diseases (30.6%). Wait times varied by diagnosis and geographic region. Overall, the median wait time from referral to rheumatologist consultation was 74 (interquartile range 27-101) days; it was 66 (interquartile range 18-84) days for systemic inflammatory rheumatic diseases. Wait time benchmarks were not achieved, even for the most urgent types of referral. For systemic inflammatory rheumatic diseases, most of the delays occurred before referral. Rheumatology wait times exceeded established benchmarks. Targeted efforts are needed to promote more timely access to both primary and rheumatology care. Routine linkage of electronic medical records with administrative data may help fill important gaps in knowledge about waits to primary and specialty care.
Marzolini, Susan; Blanchard, Chris; Alter, David A; Grace, Sherry L; Oh, Paul I
2015-11-01
Cardiac rehabilitation (CR) is recommended after coronary artery bypass graft surgery; however, the consequences of longer wait times to start CR have not been elucidated. Cardiopulmonary, demographic, and anthropometric assessments were conducted before and after 6 months of CR in consecutively enrolled patients from January 1995 to October 2012. Wait times were ascertained from referral forms and charts. Neighborhood characteristics were ascertained using census data and cross-referencing with patients' home geographic location. Among 6497 post- coronary artery bypass graft participants, mean and median total wait time (time from surgery to first exercise session) was 101.1±47.9 and 80 days, respectively. In multiple linear regression, correlates of longer total wait time and the 2 wait-time phases, time from surgery to CR referral and time from CR referral to first exercise session, were determined. Factors influencing longer wait times included female sex, greater age, being employed, less social support, longer drive time to CR, lower neighborhood socioeconomic status, higher systolic blood pressure, abdominal obesity, and a complex medical history. After adjusting for correlates of delayed entry, longer wait time for each of the total and 2 wait-time phases was significantly associated with less improvement in cardiopulmonary fitness (VO2peak; β=-0.165, P<0.001), body fat percentage (β=0.032, P<0.02), resting heart rate (β=0.066, P<0.001), and poorer attendance to CR classes (β=-0.081, P<0.001) and completion rate (β=2.741, P<0.001). Strategies for timely access to CR at each phase of the process are important given the negative impact that wait time has on key clinical outcomes. This is relevant because optimizing VO2peak and attendance to CR has been shown to confer a mortality advantage. © 2015 American Heart Association, Inc.
Patient satisfaction with nursing care in an urban and suburban emergency department.
Wright, Greg; Causey, Sherry; Dienemann, Jacqueline; Guiton, Paula; Coleman, Frankie Sue; Nussbaum, Marcy
2013-10-01
Patient satisfaction is an important outcome measurement in the emergency department (ED). When unavoidable, the negative effect of patient wait time may be lessened by communicating expected wait time, affective support, health information, decisional control, and competent providers. This controlled quasi-experimental design used a convenience sample. The patient questionnaire included demographics, expected and perceived wait time, receiving of comfort items, information and engaging activities and their perceived helpfulness for coping with waiting, and the Consumer Emergency Care Satisfaction Scale measure of patient satisfaction with nursing. Systematic offering of comfort items, clinical information, and engaging activities were statistically analyzed for impact on perceived wait times, helpfulness in waiting, and satisfaction with nursing care. Interventions were supported by the data as helpful for coping with waiting and were significantly related to nursing care satisfaction. Interventions were less helpful for suburban patients who were also less satisfied. Nurses can influence patient satisfaction in the ED through communication and caring behaviors.
FAST TRACK COMMUNICATION: Suppressing anomalous diffusion by cooperation
NASA Astrophysics Data System (ADS)
Dybiec, Bartłomiej
2010-08-01
Within a continuous time random walk scenario we consider a motion of a complex of particles which moves coherently. The motion of every particle is characterized by the waiting time and jump length distributions which are of the power-law type. Due to the interactions between particles it is assumed that the waiting time is adjusted to the shortest or to the longest waiting time. Analogously, the jump length is adjusted to the shortest or to the longest jump length. We show that adjustment to the shortest waiting time can suppress the subdiffusive behavior even in situations when the exponent characterizing the waiting time distribution assures subdiffusive motion of a single particle. Finally, we demonstrate that the characteristic of the motion depends on the number of particles building a complex.
Willis, William Kent; Ozturk, Ahmet Ozzie; Chandra, Ashish
2015-01-01
Patients have to wait in waiting rooms prior to seeing the physician. But there are few studies that demonstrate what they are actually doing in the waiting room. This exploratory study was designed to investigate the types of discussions that patients in the waiting room typically engage in with other patients and how the conversations affected their opinion on general reputation of the clinic, injections/blocks as treatment procedures, waiting time, time spent with the caregiver, overall patient satisfaction, and the pain medication usage policy. The study demonstrates that patient interaction in the waiting room has a positive effect on patient opinion of the pain clinic and the caregivers.
Continuous-Time Finance and the Waiting Time Distribution: Multiple Characteristic Times
NASA Astrophysics Data System (ADS)
Fa, Kwok Sau
2012-09-01
In this paper, we model the tick-by-tick dynamics of markets by using the continuous-time random walk (CTRW) model. We employ a sum of products of power law and stretched exponential functions for the waiting time probability distribution function; this function can fit well the waiting time distribution for BUND futures traded at LIFFE in 1997.
Improved estimation of commuter waiting times using headway and commuter boarding information
NASA Astrophysics Data System (ADS)
Ramli, Muhamad Azfar; Jayaraman, Vasundhara; Kwek, Hyen Chee; Tan, Kian Heong; Lee Kee Khoon, Gary; Monterola, Christopher
2018-07-01
The average amount of waiting time spent by commuters is one of the key indicators of service quality for public bus operations. While actual measurements of actual waiting time is difficult to be done en masse, models of waiting time can be derived from bus headways and these models have been adopted by transport planners in monitoring and regulating service reliability of operators. However, these models are founded on several assumptions on the patterns of commuter arrival which may not be applicable for bus services that experience high demand and heavily fluctuating commuter patterns. Given the availability of granular data on commuter boarding from automated fare collection systems, we propose a new methodology to better estimate the average waiting time of commuters. The formulation is anchored and validated using a three-month dataset from ten selected bus routes in Singapore. Finally, we discuss how our new measure allows for minimization of commuter waiting time through schedule optimization.
Computational Approaches to Simulation and Optimization of Global Aircraft Trajectories
NASA Technical Reports Server (NTRS)
Ng, Hok Kwan; Sridhar, Banavar
2016-01-01
This study examines three possible approaches to improving the speed in generating wind-optimal routes for air traffic at the national or global level. They are: (a) using the resources of a supercomputer, (b) running the computations on multiple commercially available computers and (c) implementing those same algorithms into NASAs Future ATM Concepts Evaluation Tool (FACET) and compares those to a standard implementation run on a single CPU. Wind-optimal aircraft trajectories are computed using global air traffic schedules. The run time and wait time on the supercomputer for trajectory optimization using various numbers of CPUs ranging from 80 to 10,240 units are compared with the total computational time for running the same computation on a single desktop computer and on multiple commercially available computers for potential computational enhancement through parallel processing on the computer clusters. This study also re-implements the trajectory optimization algorithm for further reduction of computational time through algorithm modifications and integrates that with FACET to facilitate the use of the new features which calculate time-optimal routes between worldwide airport pairs in a wind field for use with existing FACET applications. The implementations of trajectory optimization algorithms use MATLAB, Python, and Java programming languages. The performance evaluations are done by comparing their computational efficiencies and based on the potential application of optimized trajectories. The paper shows that in the absence of special privileges on a supercomputer, a cluster of commercially available computers provides a feasible approach for national and global air traffic system studies.
NASA Astrophysics Data System (ADS)
Ahangaran, Daryoush Kaveh; Yasrebi, Amir Bijan; Wetherelt, Andy; Foster, Patrick
2012-10-01
Application of fully automated systems for truck dispatching plays a major role in decreasing the transportation costs which often represent the majority of costs spent on open pit mining. Consequently, the application of a truck dispatching system has become fundamentally important in most of the world's open pit mines. Recent experiences indicate that by decreasing a truck's travelling time and the associated waiting time of its associated shovel then due to the application of a truck dispatching system the rate of production will be considerably improved. Computer-based truck dispatching systems using algorithms, advanced and accurate software are examples of these innovations. Developing an algorithm of a computer- based program appropriated to a specific mine's conditions is considered as one of the most important activities in connection with computer-based dispatching in open pit mines. In this paper the changing trend of programming and dispatching control algorithms and automation conditions will be discussed. Furthermore, since the transportation fleet of most mines use trucks with different capacities, innovative methods, operational optimisation techniques and the best possible methods for developing the required algorithm for real-time dispatching are selected by conducting research on mathematical-based planning methods. Finally, a real-time dispatching model compatible with the requirement of trucks with different capacities is developed by using two techniques of flow networks and integer programming.
Waiting times for cancer patients in Sweden: A nationwide population-based study.
Robertson, Stephanie; Adolfsson, Jan; Stattin, Pär; Sjövall, Annika; Winnersjö, Rocio; Hanning, Marianne; Sandelin, Kerstin
2017-05-01
The reported long waiting times for cancer patients have mostly been related to prognostic outcome and less to patient-related experience to outcome. We assessed waiting times for patients with cancer of the breast, prostate, colon or rectum in Sweden. The median time from referral to start of treatment was assessed using data from clinical cancer registers for patients who received curative treatment during 2011, 2012 and 2013. The median overall waiting time in different counties ranged from 7 to 28 days for breast cancer, from 117 to 280 days for prostate cancer, from 27 to 64 days for colon cancer and from 48 to 80 days for rectal cancer. For the entire nation, the median time from referral to start of treatment remained unchanged from 2011 to 2013 for each cancer diagnosis. Large variations were found in waiting times between different counties in Sweden and between different types of cancer. The long waiting times identified in this study emphasize the need to improve national programmes for more rapid diagnosis and treatment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yamada, T; Fujii, Y; Hitachi Ltd., Hitachi-shi, Ibaraki
2015-06-15
Purpose: We have developed a gated spot scanning proton beam therapy system with real-time tumor-tracking. This system has the ability of multiple-gated irradiation in a single synchrotron operation cycle controlling the wait-time for consecutive gate signals during a flat-top phase so that the decrease in irradiation efficiency induced by irregular variation of gate signal is reduced. Our previous studies have shown that a 200 ms wait-time is appropriate to increase the average irradiation efficiency, but the optimal wait-time can vary patient by patient and day by day. In this research, we have developed an evaluation system of the optimal wait-timemore » in each irradiation based on the log data of the real-time-image gated proton beam therapy (RGPT) system. Methods: The developed system consists of logger for operation of RGPT system and software for evaluation of optimal wait-time. The logger records timing of gate on/off, timing and the dose of delivered beam spots, beam energy and timing of X-ray irradiation. The evaluation software calculates irradiation time in the case of different wait-time by simulating the multiple-gated irradiation operation using several timing information. Actual data preserved in the log data are used for gate on and off time, spot irradiation time, and time moving to the next spot. Design values are used for the acceleration and deceleration times. We applied this system to a patient treated with the RGPT system. Results: The evaluation system found the optimal wait-time of 390 ms that reduced the irradiation time by about 10 %. The irradiation time with actual wait-time used in treatment was reproduced with accuracy of 0.2 ms. Conclusion: For spot scanning proton therapy system with multiple-gated irradiation in one synchrotron operation cycle, an evaluation system of the optimal wait-time in each irradiation based on log data has been developed. Funding Support: Japan Society for the Promotion of Science (JSPS) through the FIRST Program.« less
Hogan, Barbara; Rasche, Christoph; von Reinersdorff, Andrea Braun
2012-06-01
The number of patients seeking treatment in emergency departments is rising, although many governments are seeking to reduce expenditure on health. Emergency departments must achieve more with the same resources or perform the same functions with fewer resources. Patients demand higher emergency clinical care quality, with low waiting times viewed as a key quality criterion by many patients. The objective of this study was to create an improved working system in emergency departments that cuts patient waiting times for first specialty physician contact. Techniques from industrial flow management were applied to the working process of an emergency department and the concept was named 'First View.' A total of 3269 patient contacts using the First View Concept during a treatment month showed statistical significance. Before introduction, a total 3230 patients in a comparative treatment month had a median waiting time before the first doctor contact of 47.6 min, a first quartile waiting time of 36.1 min, and a third quartile waiting time of 62.7 min. After introduction, 3269 patients had a median waiting time before first specialty physician contact of 11.2 min, a first quartile waiting time of 9.1 min, and a third quartile waiting time of 15.2 min. Industrial flow concepts can achieve significant improvements in emergency department workflows in countries in which sufficient numbers of specialty physicians are available. More attention to the organization of emergency department working processes is needed, especially involving lean management.
Outpatient Waiting Time in Health Services and Teaching Hospitals: A Case Study in Iran
Mohebbifar, Rafat; Hasanpoor, Edris; Mohseni, Mohammad; Sokhanvar, Mobin; Khosravizadeh, Omid; Isfahani, Haleh Mousavi
2014-01-01
Background: One of the most important indexes of the health care quality is patient’s satisfaction and it takes place only when there is a process based on management. One of these processes in the health care organizations is the appropriate management of the waiting time process. The aim of this study is the systematic analyzing of the outpatient waiting time. Methods: This descriptive cross sectional study conducted in 2011 is an applicable study performed in the educational and health care hospitals of one of the medical universities located in the north west of Iran. Since the distributions of outpatients in all the months were equal, sampling stage was used. 160 outpatients were studied and the data was analyzed by using SPSS software. Results: Results of the study showed that the waiting time for the outpatients of ophthalmology clinic with an average of 245 minutes for each patient allocated the maximum time among the other clinics for itself. Orthopedic clinic had the minimal waiting time including an average of 77 minutes per patient. The total average waiting time for each patient in the educational hospitals under this study was about 161 minutes. Conclusion: by applying some models, we can reduce the waiting time especially in the realm of time and space before the admission to the examination room. Utilizing the models including the one before admission, electronic visit systems via internet, a process model, six sigma model, queuing theory model and FIFO model, are the components of the intervention that reduces the outpatient waiting time. PMID:24373277
Lean techniques for the improvement of patients’ flow in emergency department
Chan, HY; Lo, SM; Lee, LLY; Lo, WYL; Yu, WC; Wu, YF; Ho, ST; Yeung, RSD; Chan, JTS
2014-01-01
BACKGROUND: Emergency departments (EDs) face problems with overcrowding, access block, cost containment, and increasing demand from patients. In order to resolve these problems, there is rising interest to an approach called “lean” management. This study aims to (1) evaluate the current patient flow in ED, (2) to identify and eliminate the non-valued added process, and (3) to modify the existing process. METHODS: It was a quantitative, pre- and post-lean design study with a series of lean management work implemented to improve the admission and blood result waiting time. These included structured re-design process, priority admission triage (PAT) program, enhanced communication with medical department, and use of new high sensitivity troponin-T (hsTnT) blood test. Triage waiting time, consultation waiting time, blood result time, admission waiting time, total processing time and ED length of stay were compared. RESULTS: Among all the processes carried out in ED, the most time consuming processes were to wait for an admission bed (38.24 minutes; SD 66.35) and blood testing result (mean 52.73 minutes, SD 24.03). The triage waiting time and end waiting time for consultation were significantly decreased. The admission waiting time of emergency medical ward (EMW) was significantly decreased from 54.76 minutes to 24.45 minutes after implementation of PAT program (P<0.05). CONCLUSION: The application of lean management can improve the patient flow in ED. Acquiescence to the principle of lean is crucial to enhance high quality emergency care and patient satisfaction. PMID:25215143
[Gender and age differences in waiting time on hospital waiting list.].
Thornórðardóttir, Steinunn; Halldórsson, Matthías; Guðmundsson, Sigurður
2002-09-01
The size of waiting lists has traditionally been viewed as a fairly good measure of the quality of health care services. No statistical analysis exists in Iceland of the length of waiting times and the potential variation between groups of patients. This study was conducted within the office of the Directorate of Health in Iceland. This location was convenient since standardized information on waiting lists is collected by the office three times a year. Variations in waiting times were studied based on gender on the one hand and on age on the other. Data from the largest waiting lists, those amounting to 400 or more patients, were included in the study. The most frequently awaited operations were identified and the groups of people waiting for them analyzed. The departments and prospective operations included in the study were: Dept. of General Surgery at the University Hospital (UH) (laparoscopic gastro-oesophageal antireflux operation), Opthalmology at UH (phakoemulsification with implantation of artificial lens in posterior chamber), Orthopedic Surgery at UH (primary total prosthetic replacement of hip joint using sement), The Rehabilitation Center at Reykjalundur (rehabilitation, not specified), Ear, Nose and Throat (ENT) at UH (tonsillectomy), and Reconstructive Surgery at UH (reduction mammoplasty with transposition of areola). The lists were sorted by gender and age, with the latter consisting of two categories, older and younger patients. Every attempt was made as to ensure similar sample sizes for both age groups within each department. Finally, the median waiting time was determined and a Mann-Whitney test conducted in order to test for significance. The median waiting time for males at the General Surgery Dept. was 73 weeks as compared to 60 weeks for females. This was the only department where the median waiting time was significantly longer for males than for females (p<0.05). At three of the departments the older group had a longer median waiting time than the younger group, 18 weeks compared to 14 at Opthalmology (p<0.001), 26 versus 17 weeks at Reykjalundur (p<0.025) and 33 versus 21 weeks at ENT (p<0.01). Waiting times for females was significantly longer than for males at two departments, Reykjalundur (21 vs. 17 weeks, p<0.05) and ENT (33 vs. 29 weeks, p<0.05). This study revealed age and gender differences in median waiting times at Icelandic hospitals. These differences were in many cases marked and statistically significant. Various explanations have been put forward, however, further research is needed in order to determine if it these differences are due to actual clinical needs assessments or to age or gender discrimination.
Evaluation of supply-side initiatives to improve access to coronary bypass surgery.
Sobolev, Boris G; Fradet, Guy; Kuramoto, Lisa; Sobolyeva, Rita; Rogula, Basia; Levy, Adrian R
2012-09-11
Guided by the evidence that delaying coronary revascularization may lead to symptom worsening and poorer clinical outcomes, expansion in cardiac surgery capacity has been recommended in Canada. Provincial governments started providing one-time and recurring increases in budgets for additional open heart surgeries to reduce waiting times. We sought to determine whether the year of decision to proceed with non-emergency coronary bypass surgery had an effect on time to surgery. Using records from a population-based registry, we studied times between decision to operate and the procedure itself. We estimated changes in the length of time that patients had to wait for non-emergency operation over 14 calendar periods that included several years when supplementary funding was available. We studied waiting times separately for patients who access surgery through a wait list and through direct admission. During two periods when supplementary funding was available, 1998-1999 and 2004-2005, the weekly rate of undergoing surgery from a wait list was, respectively, 50% and 90% higher than in 1996-1997, the period with the longest waiting times. We also observed a reduction in the difference between 90th and 50th percentiles of the waiting-time distributions. Forty percent of patients in the 1998, 1999, 2004 and 2005 cohorts (years when supplementary funding was provided) underwent surgery within 16 to 20 weeks following the median waiting time, while it took between 27 and 37 weeks for the cohorts registered in the years when supplementary funding was not available. Times between decision and surgery were shorter for direct admissions than for wait-listed patients. Among patients who were directly admitted to hospital, time between decision and surgery was longest in 1992-1993 and then has been steadily decreasing through the late nineties. The rate of surgery among these patients was the highest in 1998-1999, and has not changed afterwards, even for years when supplementary funding was provided. Waiting times for non-emergency coronary bypass surgery shortened after supplementary funding was granted to increase volume of cardiac surgical care in a health system with publicly-funded universal coverage for the procedure. The effect of the supplementary funding was not uniform for patients that access the services through wait lists and through direct admission.
Brealey, S; Andronis, L; Dale, V; Gibbon, A J; Gilbert, F J; Hendry, M; Hood, K; King, D; Wilkinson, C
2012-11-01
The purpose of this study was to test for the effect of waiting time from general practitioner (GP) referral to MRI or to orthopaedic consultation on outcomes of patients with knee problems, and to test whether any characteristics of trial participants predicted waiting time to MRI or orthopaedics. We undertook secondary analyses of data on 553 participants from a randomised trial who were recruited from 163 general practices during November 2002 to October 2004. Of the patients allocated to MRI, 263 (94%) had an MRI, and of those referred to orthopaedics, 236 (86%) had an orthopaedic consultation. The median (interquartile range) waiting time in days from randomisation to MRI was 41.0 (21.0-71.0) and to orthopaedic appointment was 78.5 (54.5-167.5). Waiting time was found to have no significant effect on patient outcome for both the Short Form 36-item (SF-36) physical functioning score (p=0.570) and the Knee Quality of Life 26-item (KQoL-26) physical functioning score (p=0.268). There was weak evidence that males waited less time for their MRI (p=0.049) and older patients waited longer for their orthopaedic referral (p=0.049). For patients who resided in the catchment areas of some centres there were significantly longer waiting times for both MRI and orthopaedic appointment. Where patients reside is a strong predictor of waiting time for access to services such as MRI or orthopaedics. There is no evidence to suggest, however, that this has a significant effect on physical well-being in the short term for patients with knee problems.
Analysis and Relative Evaluation of Connectivity of a Mobile Multi-Hop Network
NASA Astrophysics Data System (ADS)
Nakano, Keisuke; Miyakita, Kazuyuki; Sengoku, Masakazu; Shinoda, Shoji
In mobile multi-hop networks, a source node S and a destination node D sometimes encounter a situation where there is no multi-hop path between them when a message M, destined for D, arrives at S. In this situation, we cannot send M from S to D immediately; however, we can deliver M to D after waiting some time with the help of two capabilities of mobility. One of the capabilities is to construct a connected multi-hop path by changing the topology of the network during the waiting time (Capability 1), and the other is to move M closer to D during the waiting time (Capability 2). In this paper, we consider three methods to deliver M from S to D by using these capabilities in different ways. Method 1 uses Capability 1 and sends M from S to D after waiting until a connected multi-hop path appears between S and D. Method 2 uses Capability 2 and delivers M to D by allowing a mobile node to carry M from S to D. Method 3 is a combination of Methods 1 and 2 and minimizes the waiting time. We evaluate and compare these three methods in terms of the mean waiting time, from the time when M arrives at S to the time when D starts receiving M, as a new approach to connectivity evaluation. We consider a one-dimensional mobile multi-hop network consisting of mobile nodes flowing in opposite directions along a street. First, we derive some approximate equations and propose an estimation method to compute the mean waiting time of Method 1. Second, we theoretically analyze the mean waiting time of Method 2, and compute a lower bound of that of Method 3. By comparing the three methods under the same assumptions using results of the analyses and some simulation results, we show relations between the mean waiting times of these methods and show how Capabilities 1 and 2 differently affect the mean waiting time.
NASA Astrophysics Data System (ADS)
Kosov, Daniel S.
2017-09-01
Quantum transport of electrons through a molecule is a series of individual electron tunneling events separated by stochastic waiting time intervals. We study the emergence of temporal correlations between successive waiting times for the electron transport in a vibrating molecular junction. Using the master equation approach, we compute the joint probability distribution for waiting times of two successive tunneling events. We show that the probability distribution is completely reset after each tunneling event if molecular vibrations are thermally equilibrated. If we treat vibrational dynamics exactly without imposing the equilibration constraint, the statistics of electron tunneling events become non-renewal. Non-renewal statistics between two waiting times τ1 and τ2 means that the density matrix of the molecule is not fully renewed after time τ1 and the probability of observing waiting time τ2 for the second electron transfer depends on the previous electron waiting time τ1. The strong electron-vibration coupling is required for the emergence of the non-renewal statistics. We show that in the Franck-Condon blockade regime, extremely rare tunneling events become positively correlated.
NASA Astrophysics Data System (ADS)
Ishigaki, Tsukasa; Yamamoto, Yoshinobu; Nakamura, Yoshiyuki; Akamatsu, Motoyuki
Patients that have an health service by doctor have to wait long time at many hospitals. The long waiting time is the worst factor of patient's dissatisfaction for hospital service according to questionnaire for patients. The present paper describes an estimation method of the waiting time for each patient without an electronic medical chart system. The method applies a portable RFID system to data acquisition and robust estimation of probability distribution of the health service and test time by doctor for high-accurate waiting time estimation. We carried out an health service of data acquisition at a real hospital and verified the efficiency of the proposed method. The proposed system widely can be used as data acquisition system in various fields such as marketing service, entertainment or human behavior measurement.
Load-sensitive dynamic workflow re-orchestration and optimisation for faster patient healthcare.
Meli, Christopher L; Khalil, Ibrahim; Tari, Zahir
2014-01-01
Hospital waiting times are considerably long, with no signs of reducing any-time soon. A number of factors including population growth, the ageing population and a lack of new infrastructure are expected to further exacerbate waiting times in the near future. In this work, we show how healthcare services can be modelled as queueing nodes, together with healthcare service workflows, such that these workflows can be optimised during execution in order to reduce patient waiting times. Services such as X-ray, computer tomography, and magnetic resonance imaging often form queues, thus, by taking into account the waiting times of each service, the workflow can be re-orchestrated and optimised. Experimental results indicate average waiting time reductions are achievable by optimising workflows using dynamic re-orchestration. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.
Waiting time care guarantees: necessity or nemesis?
Joshi, N P; Noseworthy, F T; Noseworthy, T W
2006-01-01
One of the priorities of governments in Canada is to reduce long waiting times for health services. This has raised the prospect of introducing waiting time care guarantees. Such guarantees affirm the healthcare system's social contract with the public and provide an entitlement to Canadians to receive timely care. There are clinical, legal and political implications, which must be considered and well managed before introduction. Other countries have ventured down this path. They teach us that waiting time care guarantees are good policy and make good sense. Correspondingly, they remind us not to make a promise we are not ready to keep.
Statistical Analysis of the First Passage Path Ensemble of Jump Processes
NASA Astrophysics Data System (ADS)
von Kleist, Max; Schütte, Christof; Zhang, Wei
2018-02-01
The transition mechanism of jump processes between two different subsets in state space reveals important dynamical information of the processes and therefore has attracted considerable attention in the past years. In this paper, we study the first passage path ensemble of both discrete-time and continuous-time jump processes on a finite state space. The main approach is to divide each first passage path into nonreactive and reactive segments and to study them separately. The analysis can be applied to jump processes which are non-ergodic, as well as continuous-time jump processes where the waiting time distributions are non-exponential. In the particular case that the jump processes are both Markovian and ergodic, our analysis elucidates the relations between the study of the first passage paths and the study of the transition paths in transition path theory. We provide algorithms to numerically compute statistics of the first passage path ensemble. The computational complexity of these algorithms scales with the complexity of solving a linear system, for which efficient methods are available. Several examples demonstrate the wide applicability of the derived results across research areas.
[Has the time arrived for the management of waiting lists?].
Bernal, E
2002-01-01
Individuals on the waiting list frequently suffer an additional risk caused by the mean time until they receive treatment; however, other individuals do not need the treatment for which they are waiting.Both arguments, which can be contrasted with empirical evidence, would be sufficient to affirm that waiting list management should be implemented, leaving aside policies that are more of less opportunistic. Opportunistic policies are understood as those providing misinformation on waiting lists or their "manipulation", and using programs of auto-coordination with the sole aim of reaching the end of the year without a waiting list of not more than six months, etc. The panorama is not completely bleak. Some management initiatives (and even Politics with a capital P) are opening the way forward and may enter the Agenda in the next few years. In this context, the application of guaranteed times of medical care or the prioritization of waiting lists according to explicit criteria should be highlighted. It is worth remembering that, except for the queues in the waiting rooms of health centers and emergency departments, waiting lists are mediated by the decision of the physician. Therefore, an essential strategy for managing waiting lists consists of attenuating the problems caused by uncertainty (or ignorance) of the patient's diagnosis or prognosis.
Impact of Lean on patient cycle and waiting times at a rural district hospital in KwaZulu-Natal
Naidoo, Logandran
2016-01-01
Background Prolonged waiting time is a source of patient dissatisfaction with health care and is negatively associated with patient satisfaction. Prolonged waiting times in many district hospitals result in many dissatisfied patients, overworked and frustrated staff, and poor quality of care because of the perceived increased workload. Aim The aim of the study was to determine the impact of Lean principles techniques, and tools on the operational efficiency in the outpatient department (OPD) of a rural district hospital. Setting The study was conducted at the Catherine Booth Hospital (CBH) – a rural district hospital in KwaZulu-Natal, South Africa. Methods This was an action research study with pre-, intermediate-, and post-implementation assessments. Cycle and waiting times were measured by direct observation on two occasions before, approximately two-weekly during, and on two occasions after Lean implementation. A standardised data collection tool was completed by the researcher at each of the six key service nodes in the OPD to capture the waiting times and cycle times. Results All six service nodes showed a reduction in cycle times and waiting times between the baseline assessment and post-Lean implementation measurement. Significant reduction was achieved in cycle times (27%; p < 0.05) and waiting times (from 11.93 to 10 min; p = 0.03) at the Investigations node. Although the target reduction was not achieved for the Consulting Room node, there was a significant reduction in waiting times from 80.95 to 74.43 min, (p < 0.001). The average efficiency increased from 16.35% (baseline) to 20.13% (post-intervention). Conclusion The application of Lean principles, tools and techniques provides hospital managers with an evidence-based management approach to resolving problems and improving quality indicators. PMID:27543283
[Women's satisfaction with waiting times for further investigation in breast cancer screening].
Molina-Barceló, Ana; Salas Trejo, Dolores; Miranda García, Josefa
2011-01-01
To determine the factors associated with satisfaction with waiting times for further investigation in breast cancer screening. We carried out a cross-sectional study by telephone survey of a representative sample of women (N=316) participating in the breast cancer screening program of the autonomous region of Valencia (Spain) who required additional tests to confirm the diagnosis. Descriptive analysis was performed by contingency tables (p<0.05) and multivariate association by odds ratios (OR) of logistic regression models (95%CI). Satisfaction with the waiting time was 78.6%. A higher risk of dissatisfaction was found in women from a "high" social class (OR=3.17; 95% CI: 1.10-9.14), those who perceived that the waiting time was "more than 2 weeks", both "since the notification of the need for further investigation until completion of the first test" (OR=15,54; 95%CI: 5,87-41,12) and "since the completion of the last test until notification of the final result" (OR=11.57; 95% CI: 2.96-45.19), and in women who experienced the attention as "worse than expected" (OR=15.40; 95% CI: 1.41-168.64). The maximum waiting time acceptable to the highest percentage of women was "up to 1 week" for each waiting period (n=47, 73.5%; n=14, 45.2%). Waiting times of no more than 1 week and never more than 2 weeks for each waiting period are recommended. Women should be given an approximate waiting time, paying special attention to women aged 45 to 54 years attending their initial screening. 2010 SESPAS. Published by Elsevier Espana. All rights reserved.
Longer wait times affect future use of VHA primary care.
Wong, Edwin S; Liu, Chuan-Fen; Hernandez, Susan E; Augustine, Matthew R; Nelson, Karin; Fihn, Stephan D; Hebert, Paul L
2017-07-29
Improving access to the Veterans Health Administration (VHA) is a high priority, particularly given statutory mandates of the Veterans Access, Choice and Accountability Act. This study examined whether patient-reported wait times for VHA appointments were associated with future reliance on VHA primary care services. This observational study examined 13,595 VHA patients dually enrolled in fee-for-service Medicare. Data sources included VHA administrative data, Medicare claims and the Survey of Healthcare Experiences of Patients (SHEP). Primary care use was defined as the number of face-to-face visits from VHA and Medicare in the 12 months following SHEP completion. VHA reliance was defined as the number of VHA visits divided by total visits (VHA+Medicare). Wait times were derived from SHEP responses measuring the usual number of days to a VHA appointment with patients' primary care provider for those seeking immediate care. We defined appointment wait times categorically: 0 days, 1day, 2-3 days, 4-7 days and >7 days. We used fractional logistic regression to examine the relationship between wait times and reliance. Mean VHA reliance was 88.1% (95% CI = 86.7% to 89.5%) for patients reporting 0day waits. Compared with these patients, reliance over the subsequent year was 1.4 (p = 0.041), 2.8 (p = 0.001) and 1.6 (p = 0.014) percentage points lower for patients waiting 2-3 days, 4-7 days and >7 days, respectively. Patients reporting longer usual wait times for immediate VHA care exhibited lower future reliance on VHA primary care. Longer wait times may reduce care continuity and impact cost shifting across two federal health programs. Copyright © 2017. Published by Elsevier Inc.
Load Balancing Scientific Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pearce, Olga Tkachyshyn
2014-12-01
The largest supercomputers have millions of independent processors, and concurrency levels are rapidly increasing. For ideal efficiency, developers of the simulations that run on these machines must ensure that computational work is evenly balanced among processors. Assigning work evenly is challenging because many large modern parallel codes simulate behavior of physical systems that evolve over time, and their workloads change over time. Furthermore, the cost of imbalanced load increases with scale because most large-scale scientific simulations today use a Single Program Multiple Data (SPMD) parallel programming model, and an increasing number of processors will wait for the slowest one atmore » the synchronization points. To address load imbalance, many large-scale parallel applications use dynamic load balance algorithms to redistribute work evenly. The research objective of this dissertation is to develop methods to decide when and how to load balance the application, and to balance it effectively and affordably. We measure and evaluate the computational load of the application, and develop strategies to decide when and how to correct the imbalance. Depending on the simulation, a fast, local load balance algorithm may be suitable, or a more sophisticated and expensive algorithm may be required. We developed a model for comparison of load balance algorithms for a specific state of the simulation that enables the selection of a balancing algorithm that will minimize overall runtime.« less
Hayes Balmadrid, Melissa A; Shelby, Rebecca A; Wren, Anava A; Miller, Lauren S; Yoon, Sora C; Baker, Jay A; Wildermann, Liz A; Soo, Mary Scott
2017-04-01
This study investigated how time from breast biopsy recommendation to biopsy procedure affected pre-biopsy anxiety ( N = 140 women), and whether the relationship between wait time and anxiety was affected by psychosocial factors (chronic life stress, traumatic events, social support). Analyses showed a significant interaction between wait time and chronic life stress. Increased time from biopsy recommendation was associated with greater anxiety in women with low levels of life stress. Women with high levels of life stress experienced increased anxiety regardless of wait time. These results suggest that women may benefit from shorter wait times and receiving strategies for managing anxiety.
Wait-Time and Multiple Representation Levels in Chemistry Lessons
ERIC Educational Resources Information Center
Li, Winnie Sim Siew; Arshad, Mohammad Yusof
2014-01-01
Wait-time is an important aspect in a teaching and learning process, especially after the teacher has posed questions to students, as it is one of the factors in determining quality of students' responses. This article describes the practices of wait-time one after teacher's questions at multiple representation levels among twenty three chemistry…
Improving Patient Satisfaction with Waiting Time
ERIC Educational Resources Information Center
Eilers, Gayleen M.
2004-01-01
Waiting times are a significant component of patient satisfaction. A patient satisfaction survey performed in the author's health center showed that students rated waiting time lowest of the listed categories--A ratings of 58% overall, 63% for scheduled appointments, and 41% for the walk-in clinic. The center used a quality improvement process and…
Effects of communication burstiness on consensus formation and tipping points in social dynamics
NASA Astrophysics Data System (ADS)
Doyle, C.; Szymanski, B. K.; Korniss, G.
2017-06-01
Current models for opinion dynamics typically utilize a Poisson process for speaker selection, making the waiting time between events exponentially distributed. Human interaction tends to be bursty though, having higher probabilities of either extremely short waiting times or long periods of silence. To quantify the burstiness effects on the dynamics of social models, we place in competition two groups exhibiting different speakers' waiting-time distributions. These competitions are implemented in the binary naming game and show that the relevant aspect of the waiting-time distribution is the density of the head rather than that of the tail. We show that even with identical mean waiting times, a group with a higher density of short waiting times is favored in competition over the other group. This effect remains in the presence of nodes holding a single opinion that never changes, as the fraction of such committed individuals necessary for achieving consensus decreases dramatically when they have a higher head density than the holders of the competing opinion. Finally, to quantify differences in burstiness, we introduce the expected number of small-time activations and use it to characterize the early-time regime of the system.
Badre, Bouchra; Serhier, Zineb; El Arabi, Samira
2014-01-01
Oral diseases may have an impact on quality of children's life. The presence of severe disability requires the use of care under general anesthesia (GA). However, because of the limited number of qualified health personnel, waiting time before intervention can be long. To evaluate the waiting time before dental care under general anesthesia for children with special needs in Morocco. A retrospective cohort study was carried out in pediatric dentistry unit of the University Hospital of Casablanca. Data were collected from records of patients seen for the first time between 2006 and 2011. The waiting time was defined as the time between the date of the first consultation and intervention date. 127 children received dental care under general anesthesia, 57.5% were male and the average age was 9.2 (SD = 3.4). Decay was the most frequent reason for consultation (48%), followed by pain (32%). The average waiting time was 7.6 months (SD = 4.2 months). The average number of acts performed per patient was 13.5. Waiting times were long, it is necessary to take measures to reduce delays and improve access to oral health care for this special population.
Ng, Jonathon Q; Lundström, Mats
2014-06-01
To evaluate waiting times for first-eye cataract surgery in Sweden following widespread adoption of the Nationell Indikationsmodell for Kataraktextraktion (NIKE) tool for prioritizing patients for cataract surgery. Waiting times for all first-eye cataract surgeries in Sweden in 2009-2011 were identified from the Swedish National Cataract Register. Waiting times were compared according to demographic, clinical and NIKE indication group for surgery. Multivariate logistic regression modelling was used to determine factors associated with waiting times less than the 3-month Government guarantee period. There were 141,070 first-eye cataract surgeries in 2009 to 2011; an annual increase of around 6%. Over the study period, mean waiting times decreased across all NIKE groups. The proportion waiting <3 months for surgery also increased across all NIKE groups. Surgery within 3 months of waitlisting was more likely for patients with a NIKE 1 indication classification (most need for surgery), in later years, male patients, younger patients and patients with a preoperative visual acuity in the better eye worse than 6/24. Prioritizing patients for cataract surgery using NIKE reduces waiting times for those with the greatest need. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
Building a sustainable system: the making of the WTIS.
Hall, Steve; Thabet, Rami; Dummett, Mark
2009-01-01
Building Ontario's Wait Time Information System (WTIS) was one of the largest and most complex technology projects Cancer Care Ontario (CCO) had ever taken on. Increasing public concern about wait times and the lack of adequate tools to provide a clear or accurate picture of provincial wait times had led to a sense of urgency for the province to report wait time data. While healthcare providers and the Ministry of Health and Long-term Care (MOHLTC) sought to address timely access to care, the challenges to develop a suitable information management/information technology (IM/IT) solution within aggressive timelines were significant. For the WTIS project, success was defined by the ability to deliver a tool to capture wait time data that addressed business and clinical needs and by providing individuals with the ability to use the tool and its data to improve access to care.
Parés, D; Duran, E; Hermoso, J; Comajuncosas, J; Gris, P; Lopez-Negre, J L; Urgellés, J; Orbeal, R; Vallverdú, H; Jimeno, J
2013-01-01
The structural resources of the National Health system are limited, and therefore early surgery cannot be performed on all patients. The objective was to analyse the satisfaction perceived by the patient as regards the delay of treatment by waiting list of three types of surgery. The influence of expectations on waiting times, and impaired quality of life due to the clinical symptoms during the delay, were studied. A prospective study was conducted using a postal questionnaire. We compared the expectations (scale of 1 to 5), the impact on quality of life for symptoms (scale of 1 to 5) and the level of patient satisfaction (scale of 1 to 5) with respect to time on the waitng list for cholelithiasis, inguinal hernia and haemorrhoids. The predictors of patient dissatisfaction were analysed. A total of 57 patients were included. When comparing the characteristics of patients with and without satisfaction over time on the waiting list, days on the waiting list (P=.044), the change in the quality of life due to the symptoms (P=.028), and expectations (P<.001) were significantly different between the two groups. In the multivariate analysis, the expectation was associated with patient dissatisfaction as regards the time on waiting list (OR: 3.14 95% CI: 5.91 to 220.73, P<.001). The level of patient dissatisfaction is associated with expectations about time in waiting list. Copyright © 2012 SECA. Published by Elsevier Espana. All rights reserved.
Arnesen, Kjell E; Erikssen, Jan; Stavem, Knut
2002-12-01
In a system with implicit queue management, to examine gender and socioeconomic status as determinants of waiting time for inpatient surgery, after adjusting for other potential predictors. A cohort of 452 subjects was examined in outpatient clinics of a general hospital and referred to inpatient surgery. They were followed until scheduled hospital admission (n=396) or until the requested procedure no longer was relevant (n=56). We compared waiting time between groups from referral date until hospital admission, using Kaplan-Meier estimates of waiting times and log rank test. A Cox proportional hazards model was used for assessing the risk ratio (RR) of hospital admission for scheduled surgery. Gender and socioeconomic status could not explain variations in waiting time. However, patients with suspected/verified neoplastic disease or a risk of serious deterioration without treatment had markedly shorter waiting times than the reference groups, with adjusted RR (95% confidence intervals (95%CI)) of time to receiving in-patient surgery of 2.3 (1.7-3.0) and 2.0 (1.3-3.0), respectively. Being on sick leave was associated with shorter waiting time, adjusted RR of 1.7 (1.2-2.5). Referrals from within the hospital or other hospitals had also shorter waiting times than referrals from primary health care physicians, adjusted RR=1.4 (1.1-1.8). There was no evidence of bias against women or people in lower socioeconomic classes in this implicit queue management system. However, patients' access to inpatient surgery was associated with malignancy, prognosis, sick leave status, physician experience, referral pattern and the major diagnosis category.
Bachmann, M O; Barron, P
1997-01-01
Long waits at large urban clinics obstruct primary care delivery, imposing time costs on patients, deterring appropriate utilization and causing patient dissatisfaction. This paper reports on an innovative attempt by staff in a large South African urban health centre to analyse a system of queues and preventive and curative services for pre-school children, and thereafter to evaluate changes. The study had a cross-sectional work study design, with repeated measurement of waiting times after 13 months. At baseline the preventive clinic was found to have several inessential processes and waits; these were eliminated or overlapped, and clinic sessions per week were increased. A year later median waiting times had decreased substantially in the preventive clinic, but had increased in the curative clinic. Simple research can explain long waits, inform and measure changes, and provide evidence to justify primary care integration and would be useful in health centres and hospital outpatient departments in developing countries.
Resource Allocation and Outpatient Appointment Scheduling Using Simulation Optimization
Ling, Teresa Wai Ching; Yeung, Wing Kwan
2017-01-01
This paper studies the real-life problems of outpatient clinics having the multiple objectives of minimizing resource overtime, patient waiting time, and waiting area congestion. In the clinic, there are several patient classes, each of which follows different treatment procedure flow paths through a multiphase and multiserver queuing system with scarce staff and limited space. We incorporate the stochastic factors for the probabilities of the patients being diverted into different flow paths, patient punctuality, arrival times, procedure duration, and the number of accompanied visitors. We present a novel two-stage simulation-based heuristic algorithm to assess various tactical and operational decisions for optimizing the multiple objectives. In stage I, we search for a resource allocation plan, and in stage II, we determine a block appointment schedule by patient class and a service discipline for the daily operational level. We also explore the effects of the separate strategies and their integration to identify the best possible combination. The computational experiments are designed on the basis of data from a study of an ophthalmology clinic in a public hospital. Results show that our approach significantly mitigates the undesirable outcomes by integrating the strategies and increasing the resource flexibility at the bottleneck procedures without adding resources. PMID:29104748
Resource Allocation and Outpatient Appointment Scheduling Using Simulation Optimization.
Lin, Carrie Ka Yuk; Ling, Teresa Wai Ching; Yeung, Wing Kwan
2017-01-01
This paper studies the real-life problems of outpatient clinics having the multiple objectives of minimizing resource overtime, patient waiting time, and waiting area congestion. In the clinic, there are several patient classes, each of which follows different treatment procedure flow paths through a multiphase and multiserver queuing system with scarce staff and limited space. We incorporate the stochastic factors for the probabilities of the patients being diverted into different flow paths, patient punctuality, arrival times, procedure duration, and the number of accompanied visitors. We present a novel two-stage simulation-based heuristic algorithm to assess various tactical and operational decisions for optimizing the multiple objectives. In stage I, we search for a resource allocation plan, and in stage II, we determine a block appointment schedule by patient class and a service discipline for the daily operational level. We also explore the effects of the separate strategies and their integration to identify the best possible combination. The computational experiments are designed on the basis of data from a study of an ophthalmology clinic in a public hospital. Results show that our approach significantly mitigates the undesirable outcomes by integrating the strategies and increasing the resource flexibility at the bottleneck procedures without adding resources.
Optimization of BEV Charging Strategy
NASA Astrophysics Data System (ADS)
Ji, Wei
This paper presents different approaches to optimize fast charging and workplace charging strategy of battery electric vehicle (BEV) drivers. For the fast charging analysis, a rule-based model was built to simulate BEV charging behavior. Monte Carlo analysis was performed to explore to the potential range of congestion at fast charging stations which could be more than four hours at the most crowded stations. Genetic algorithm was performed to explore the theoretical minimum waiting time at fast charging stations, and it can decrease the waiting time at the most crowded stations to be shorter than one hour. A deterministic approach was proposed as a feasible suggestion that people should consider to take fast charging when the state of charge is approaching 40 miles. This suggestion is hoped to help to minimize potential congestion at fast charging stations. For the workplace charging analysis, scenario analysis was performed to simulate temporal distribution of charging demand under different workplace charging strategies. It was found that if BEV drivers charge as much as possible and as late as possible at workplace, it could increase the utility of solar-generated electricity while relieve grid stress of extra intensive electricity demand at night caused by charging electric vehicles at home.
Community Care Administration of Spinal Deformities in the Brazilian Public Health System.
Bressan-Neto, Mario; da Silva Herrero, Carlos Fernando Pereira; Pacola, Lilian Maria; Nunes, Altacílio Aparecido; Defino, Helton Luiz Aparecido
2017-08-01
Underfunding of the surgical treatment of complex spinal deformities has been an important reason for the steadily growing waiting lists in publicly funded healthcare systems. The aim of this study is to characterize the management of the treatment of spinal deformities in the public healthcare system. A cross-sectional study of 60 patients with complex pediatric spinal deformities waiting for treatment in December 2013 was performed. The evaluated parameters were place of origin, waiting time until first assessment at a specialized spine care center, waiting time for the surgical treatment, and need for implants not reimbursed by the healthcare system. Ninety-one percent of the patients lived in São Paulo State (33% from Ribeirão Preto - DRS XIII). Patients waited for 0.5 to 48.0 months for referral, and the waiting times for surgery ranged from 2 to 117 months. Forty-five percent of the patients required implants for the surgical procedure that were not available. The current management of patients with spinal deformities in the public healthcare system does not provide adequate treatment for these patients in our region. They experience long waiting periods for referral and prolonged waiting times to receive surgical treatment; additionally, many of the necessary procedures are not reimbursed by the public healthcare system.
Ribera, Aida; Slof, John; Ferreira-González, Ignacio; Serra, Vicente; García-Del Blanco, Bruno; Cascant, Purificació; Andrea, Rut; Falces, Carlos; Gutiérrez, Enrique; Del Valle-Fernández, Raquel; Morís-de laTassa, César; Mota, Pedro; Oteo, Juan Francisco; Tornos, Pilar; García-Dorado, David
2017-11-23
The economic crisis in Europe might have limited access to some innovative technologies implying an increase of waiting time. The purpose of the study is to evaluate the impact of waiting time on the costs and benefits of transcatheter aortic valve replacement (TAVR) for the treatment of severe aortic stenosis. This is a cost-utility analysis from the perspective of the Spanish National Health Service. Results of two prospective hospital registries (158 and 273 consecutive patients) were incorporated into a probabilistic Markov model to compare quality adjusted life years (QALYs) and costs for TAVR after waiting for 3-12 months, relative to immediate TAVR. We simulated a cohort of 1000 patients, male, and 80 years old; other patient profiles were assessed in sensitivity analyses. As waiting time increased, costs decreased at the expense of lower survival and loss of QALYs, leading to incremental cost-effectiveness ratios for eliminating waiting lists of about 12,500 € per QALY. In subgroup analyses prioritization of patients for whom higher benefit was expected led to a smaller loss of QALYs. Concerning budget impact, long waiting lists reduced spending considerably and permanently. A shorter waiting time is likely to be cost-effective (considering commonly accepted willingness-to-pay thresholds in Europe) relative to 3 months or longer waiting periods. If waiting lists are nevertheless seen as unavoidable due to severe but temporary budgetary restrictions, prioritizing patients for whom higher benefit is expected appears to be a way of postponing spending without utterly sacrificing patients' survival and quality of life.
Methodology for Analysis, Modeling and Simulation of Airport Gate-waiting Delays
NASA Astrophysics Data System (ADS)
Wang, Jianfeng
This dissertation presents methodologies to estimate gate-waiting delays from historical data, to identify gate-waiting-delay functional causes in major U.S. airports, and to evaluate the impact of gate operation disruptions and mitigation strategies on gate-waiting delay. Airport gates are a resource of congestion in the air transportation system. When an arriving flight cannot pull into its gate, the delay it experiences is called gate-waiting delay. Some possible reasons for gate-waiting delay are: the gate is occupied, gate staff or equipment is unavailable, the weather prevents the use of the gate (e.g. lightning), or the airline has a preferred gate assignment. Gate-waiting delays potentially stay with the aircraft throughout the day (unless they are absorbed), adding costs to passengers and the airlines. As the volume of flights increases, ensuring that airport gates do not become a choke point of the system is critical. The first part of the dissertation presents a methodology for estimating gate-waiting delays based on historical, publicly available sources. Analysis of gate-waiting delays at major U.S. airports in the summer of 2007 identifies the following. (i) Gate-waiting delay is not a significant problem on majority of days; however, the worst delay days (e.g. 4% of the days at LGA) are extreme outliers. (ii) The Atlanta International Airport (ATL), the John F. Kennedy International Airport (JFK), the Dallas/Fort Worth International Airport (DFW) and the Philadelphia International Airport (PHL) experience the highest gate-waiting delays among major U.S. airports. (iii) There is a significant gate-waiting-delay difference between airlines due to a disproportional gate allocation. (iv) Gate-waiting delay is sensitive to time of a day and schedule peaks. According to basic principles of queueing theory, gate-waiting delay can be attributed to over-scheduling, higher-than-scheduled arrival rate, longer-than-scheduled gate-occupancy time, and reduced gate availability. Analysis of the worst days at six major airports in the summer of 2007 indicates that major gate-waiting delays are primarily due to operational disruptions---specifically, extended gate occupancy time, reduced gate availability and higher-than-scheduled arrival rate (usually due to arrival delay). Major gate-waiting delays are not a result of over-scheduling. The second part of this dissertation presents a simulation model to evaluate the impact of gate operational disruptions and gate-waiting-delay mitigation strategies, including building new gates, implementing common gates, using overnight off-gate parking and adopting self-docking gates. Simulation results show the following effects of disruptions: (i) The impact of arrival delay in a time window (e.g. 7 pm to 9 pm) on gate-waiting delay is bounded. (ii) The impact of longer-than-scheduled gate-occupancy times in a time window on gate-waiting delay can be unbounded and gate-waiting delay can increase linearly as the disruption level increases. (iii) Small reductions in gate availability have a small impact on gate-waiting delay due to slack gate capacity, while larger reductions have a non-linear impact as slack gate capacity is used up. Simulation results show the following effects of mitigation strategies: (i) Implementing common gates is an effective mitigation strategy, especially for airports with a flight schedule not dominated by one carrier, such as LGA. (ii) The overnight off-gate rule is effective in mitigating gate-waiting delay for flights stranded overnight following departure cancellations. This is especially true at airports where the gate utilization is at maximum overnight, such as LGA and DFW. The overnight off-gate rule can also be very effective to mitigate gate-waiting delay due to operational disruptions in evenings. (iii) Self-docking gates are effective in mitigating gate-waiting delay due to reduced gate availability.
Casimiro Pérez, José Antonio; Fernández Quesada, Carlos; Del Val Groba Marco, María; Arteaga González, Iván; Cruz Benavides, Francisco; Ponce, Jaime; de Pablos Velasco, Pedro; Marchena Gómez, Joaquín
2018-04-01
In the last decades, we have experienced an increase in the prevalence of obesity in western countries with a higher demand for bariatric surgery and consequently prolonged waiting times. Currently, in many public hospitals, the only criterion that establishes priority for bariatric surgery is waiting time regardless of obesity severity. We propose a new, simple, and homogeneous clinical prioritization system, the Obesity Surgery Score (OSS), which takes into account simultaneously and equitably the time on surgical waiting list and the obesity severity based on three variables: body mass index, obesity-related comorbidities, and functional limitations. We have reviewed the current literature related to obesity clinical staging systems, and we have carried out an analysis of our patients in waiting list and divided their characteristics according to their degree of severity (A, B, or C) in the OSS. Patients with OSS grade C have a higher mean BMI, greater severity in comorbidities, and greater socio-labor impact. The current surgery waiting time of our series is of 26 months. Currently, 27 patients (51.9%) with OSS grade B and 15 patients (51.7%) with OSS grade C have been on our waiting list for more than 1 year. Since the obesity severity, the waiting time and its clinical consequences are associated with an increase in morbidity and mortality, it is important to apply a structured prioritization system for bariatric surgery waiting list. This allows prioritization of patients at greater risk, improves patient prognosis, and optimizes costs and available health resources.
Waiting time distributions in financial markets
NASA Astrophysics Data System (ADS)
Sabatelli, L.; Keating, S.; Dudley, J.; Richmond, P.
2002-05-01
We study waiting time distributions for data representing two completely different financial markets that have dramatically different characteristics. The first are data for the Irish market during the 19th century over the period 1850 to 1854. A total of 10 stocks out of a database of 60 are examined. The second database is for Japanese yen currency fluctuations during the latter part of the 20th century (1989-1992). The Irish stock activity was recorded on a daily basis and activity was characterised by waiting times that varied from one day to a few months. The Japanese yen data was recorded every minute over 24 hour periods and the waiting times varied from a minute to a an hour or so. For both data sets, the waiting time distributions exhibit power law tails. The results for Irish daily data can be easily interpreted using the model of a continuous time random walk first proposed by Montroll and applied recently to some financial data by Mainardi, Scalas and colleagues. Yen data show a quite different behaviour. For large waiting times, the Irish data exhibit a cut off; the Yen data exhibit two humps that could arise as result of major trading centres in the World.
Effects of Wait Time When Communicating with Children Who Have Sensory and Additional Disabilities
ERIC Educational Resources Information Center
Johnson, Nicole; Parker, Amy T.
2013-01-01
Introduction: This study utilized wait-time procedures to determine if they are effective in helping children with deafblindness or multiple disabilities that include a visual impairment communicate in their home. Methods: A single subject with an alternating treatment design was used for the study. Zero- to one-second wait time was utilized…
Fractional Poisson-Nernst-Planck Model for Ion Channels I: Basic Formulations and Algorithms.
Chen, Duan
2017-11-01
In this work, we propose a fractional Poisson-Nernst-Planck model to describe ion permeation in gated ion channels. Due to the intrinsic conformational changes, crowdedness in narrow channel pores, binding and trapping introduced by functioning units of channel proteins, ionic transport in the channel exhibits a power-law-like anomalous diffusion dynamics. We start from continuous-time random walk model for a single ion and use a long-tailed density distribution function for the particle jump waiting time, to derive the fractional Fokker-Planck equation. Then, it is generalized to the macroscopic fractional Poisson-Nernst-Planck model for ionic concentrations. Necessary computational algorithms are designed to implement numerical simulations for the proposed model, and the dynamics of gating current is investigated. Numerical simulations show that the fractional PNP model provides a more qualitatively reasonable match to the profile of gating currents from experimental observations. Meanwhile, the proposed model motivates new challenges in terms of mathematical modeling and computations.
Enhancing the Selection of Backoff Interval Using Fuzzy Logic over Wireless Ad Hoc Networks
Ranganathan, Radha; Kannan, Kathiravan
2015-01-01
IEEE 802.11 is the de facto standard for medium access over wireless ad hoc network. The collision avoidance mechanism (i.e., random binary exponential backoff—BEB) of IEEE 802.11 DCF (distributed coordination function) is inefficient and unfair especially under heavy load. In the literature, many algorithms have been proposed to tune the contention window (CW) size. However, these algorithms make every node select its backoff interval between [0, CW] in a random and uniform manner. This randomness is incorporated to avoid collisions among the nodes. But this random backoff interval can change the optimal order and frequency of channel access among competing nodes which results in unfairness and increased delay. In this paper, we propose an algorithm that schedules the medium access in a fair and effective manner. This algorithm enhances IEEE 802.11 DCF with additional level of contention resolution that prioritizes the contending nodes according to its queue length and waiting time. Each node computes its unique backoff interval using fuzzy logic based on the input parameters collected from contending nodes through overhearing. We evaluate our algorithm against IEEE 802.11, GDCF (gentle distributed coordination function) protocols using ns-2.35 simulator and show that our algorithm achieves good performance. PMID:25879066
Primary hip and knee replacement surgery: Ontario criteria for case selection and surgical priority.
Naylor, C D; Williams, J I
1996-01-01
OBJECTIVES--To develop, from simple clinical factors, criteria to identify appropriate patients for referral to a surgeon for consideration for arthroplasty, and to rank them in the queue once surgery is agreed. DESIGN--Delphi process, with a panel including orthopaedic surgeons, rheumatologists, general practitioners, epidemiologists, and physiotherapists, who rated 120 case scenarios for appropriateness and 42 for waiting list priority. Scenarios incorporated combinations of relevant clinical factors. It was assumed that queues should be organised not simply by chronology but by clinical and social impact of delayed surgery. The panel focused on information obtained from clinical histories, to ensure the utility of the guidelines in practice. Relevant high quality research evidence was limited. SETTING--Ontario, Canada. MAIN MEASURES--Appropriateness ratings on a 7-point scale, and urgency rankings on a 4-point scale keyed to specific waiting times. RESULTS--Despite incomplete evidence panellists agreed on ratings in 92.5% of appropriateness and 73.8% of urgency scenarios versus 15% and 18% agreement expected by chance, respectively. Statistically validated algorithms in decision tree form, which should permit rapid estimation of urgency or appropriateness in practice, were compiled by recursive partitioning. Rating patterns and algorithms were also used to make brief written guidelines on how clinical factors affect appropriateness and urgency of surgery. A summary score was provided for each case scenario; scenarios could then be matched to chart audit results, with scoring for quality management. CONCLUSIONS--These algorithms and criteria can be used by managers or practitioners to assess appropriateness of referral for hip or knee replacement and relative rankings of patients in the queue for surgery. PMID:10157268
de Neree Tot Babberich, M P M; van der Willik, E M; van Groningen, J T; Ledeboer, M; Wiggers, T; Wouters, M W J M
2017-01-01
To investigate the impact of the Netherlands national colorectal cancer screening programme on the number of surgical resections for colorectal carcinoma and on waiting times for surgery. Descriptive study. Data were extracted from the Dutch Surgical Colorectal Audit. Patients with primary colorectal cancer surgery between 2011-2015 were included. The volume and median waiting times for the years 2011-2015 are described. Waiting times from first tumor positive biopsy until the operation (biopsy-operation) and first preoperative visit to the surgeon until the operation (visit-operation) are analyzed with a univariate and multivariate linear regression analysis. Separate analysis was done for visit-operation for academic and non-academic hospitals and for screening compared to non-screening patients. In 2014 there was an increase of 1469 (15%) patients compared to 2013. In 2015 this increase consisted of 1168 (11%) patients compared to 2014. In 2014 and 2015, 1359 (12%) and 3111 (26%) patients were referred to the surgeon through screening, respectively. The median waiting time of biopsy-operation significantly decreased (ß: 0.94, 95%BI) over the years 2014-2015 compared to 2011-2013. In non-academic hospitals, the waiting time visit-operation also decreased significantly (ß: 0.89, 95%BI 0.87-0.90) over the years 2014-2015 compared to 2011-2013. No difference was found in waiting times between patients referred to the surgeon through screening compared to non-screening. There is a clear increase in volume since the introduction of the colorectal cancer screening programme without an increase in waiting time until surgery.
Heart Surgery Waiting Time: Assessing the Effectiveness of an Action.
Badakhshan, Abbas; Arab, Mohammad; Gholipour, Mahin; Behnampour, Naser; Saleki, Saeid
2015-08-01
Waiting time is an index assessing patient satisfaction, managerial effectiveness and horizontal equity in providing health care. Although heart surgery centers establishment is attractive for politicians. They are always faced with the question of to what extent they solve patient's problems. The objective of this study was to evaluate factors influencing waiting time in patients of heart surgery centers, and to make recommendations for health-care policy-makers for reducing waiting time and increasing the quality of services from this perspective. This cross-sectional study was performed in 2013. After searching articles on PubMed, Elsevier, Google Scholar, Ovid, Magiran, IranMedex, and SID, a list of several criteria, which relate to waiting time, was provided. Afterwards, the data on waiting time were collected by a researcher-structured checklist from 156 hospitalized patients. The data were analyzed by SPSS 16. The Kolmogorov Smirnov and Shapiro tests were used for determination of normality. Due to the non-normal distribution, non-parametric tests, such as Kruskal-Wallis and Mann-Whitney were chosen for reporting significance. Parametric tests also used reporting medians. Among the studied variables, just economic status had a significant relation with waiting time (P = 0.37). Fifty percent of participants had diabetes, whereas this estimate was 43.58% for high blood pressure. As the cause of delay, 28.2% of patients reported financial problems, 18.6% personal problem and 13.5% a delay in providing equipment by the hospital. It seems the studied hospital should review its waiting time arrangements and detach them, as far as possible, from subjective and personal (specialists) decisions. On the other hand, ministries of health and insurance companies should consider more financial support. It is also recommend that hospitals should arrange preoperational psychiatric consultation for increasing patients' emotionally readiness.
A research on motion design for APP's loading pages based on time perception
NASA Astrophysics Data System (ADS)
Cao, Huai; Hu, Xiaoyun
2018-04-01
Due to restrictions caused by objective reasons like network bandwidth, hardware performance and etc., waiting is still an inevitable phenomenon that appears in our using mobile-terminal products. Relevant researches show that users' feelings in a waiting scenario can affect their evaluations on the whole product and services the product provides. With the development of user experience and inter-facial design subjects, the role of motion effect in the interface design has attracted more and more scholars' attention. In the current studies, the research theory of motion design in a waiting scenario is imperfect. This article will use the basic theory and experimental research methods of cognitive psychology to explore the motion design's impact on user's time perception when users are waiting for loading APP pages. Firstly, the article analyzes the factors that affect waiting experience of loading APP pages based on the theory of time perception, and then discusses motion design's impact on the level of time-perception when loading pages and its design strategy. Moreover, by the operation analysis of existing loading motion designs, the article classifies the existing loading motions and designs an experiment to verify the impact of different types of motions on the user's time perception. The result shows that the waiting time perception of mobile's terminals' APPs is related to the loading motion types, the combination type of loading motions can effectively shorten the waiting time perception as it scores a higher mean value in the length of time perception.
Waiting for coronary angiography: is there a clinically ordered queue?
Hemingway, H; Crook, A M; Feder, G; Dawson, J R; Timmis, A
2000-03-18
Among over 3000 patients undergoing coronary angiography in the absence of a formal queue-management system, we found that a-priori urgency scores were strongly associated with waiting times, prevalence of coronary-artery disease, rate of revascularisation, and mortality. These data challenge the widely held assumption that such waiting lists are not clinically ordered; however, the wide variation in waiting times within urgency categories suggests the need for further improvements in clinical queueing.
Extended shortest path selection for package routing of complex networks
NASA Astrophysics Data System (ADS)
Ye, Fan; Zhang, Lei; Wang, Bing-Hong; Liu, Lu; Zhang, Xing-Yi
The routing strategy plays a very important role in complex networks such as Internet system and Peer-to-Peer networks. However, most of the previous work concentrates only on the path selection, e.g. Flooding and Random Walk, or finding the shortest path (SP) and rarely considering the local load information such as SP and Distance Vector Routing. Flow-based Routing mainly considers load balance and still cannot achieve best optimization. Thus, in this paper, we propose a novel dynamic routing strategy on complex network by incorporating the local load information into SP algorithm to enhance the traffic flow routing optimization. It was found that the flow in a network is greatly affected by the waiting time of the network, so we should not consider only choosing optimized path for package transformation but also consider node congestion. As a result, the packages should be transmitted with a global optimized path with smaller congestion and relatively short distance. Analysis work and simulation experiments show that the proposed algorithm can largely enhance the network flow with the maximum throughput within an acceptable calculating time. The detailed analysis of the algorithm will also be provided for explaining the efficiency.
Heterogeneous nucleation of aspartame from aqueous solutions
NASA Astrophysics Data System (ADS)
Kubota, Noriaki; Kinno, Hiroaki; Shimizu, Kenji
1990-03-01
Waiting times, the time from the instant of quenching needed for a first nucleus to appear, were measured at constant supercoolings for primary nucleation of aspartame (α-L-aspartyl-L-phenylalanine methylester) from aqueous solutions, which were sealed into glass ampoules (solution volume = 3.16 cm 3). Since the waiting time became shorter by filtering the solution prior to quenching, the nucleation was concluded to be heterogeneously induced. The measured waiting time consisted of two parts: time needed for the nucleus to grow to a detactable size (growth time) and stochastic time needed for nucleation (true waiting time). The distribution of the true waiting time, is well explained by a stochastic model, in which nucleation is regarded to occur heterogeneously and in a stochastic manner by two kinds of active sites. The active sites are estimated to be located on foreign particles in which such elements as Si, Al and Mg were contained. The amount of each element is very small in the order of magnitude of ppb (mass basis) of the whole solution. The growth time was correlated with the degree of supercooling.
Introducing heterogeneous users and vehicles into models and algorithms for the dial-a-ride problem.
Parragh, Sophie N
2011-08-01
Dial-a-ride problems deal with the transportation of people between pickup and delivery locations. Given the fact that people are subject to transportation, constraints related to quality of service are usually present, such as time windows and maximum user ride time limits. In many real world applications, different types of users exist. In the field of patient and disabled people transportation, up to four different transportation modes can be distinguished. In this article we consider staff seats, patient seats, stretchers and wheelchair places. Furthermore, most companies involved in the transportation of the disabled or ill dispose of different types of vehicles. We introduce both aspects into state-of-the-art formulations and branch-and-cut algorithms for the standard dial-a-ride problem. Also a recent metaheuristic method is adapted to this new problem. In addition, a further service quality related issue is analyzed: vehicle waiting time with passengers aboard. Instances with up to 40 requests are solved to optimality. High quality solutions are obtained with the heuristic method.
Alvarado, Michelle; Ntaimo, Lewis
2018-03-01
Oncology clinics are often burdened with scheduling large volumes of cancer patients for chemotherapy treatments under limited resources such as the number of nurses and chairs. These cancer patients require a series of appointments over several weeks or months and the timing of these appointments is critical to the treatment's effectiveness. Additionally, the appointment duration, the acuity levels of each appointment, and the availability of clinic nurses are uncertain. The timing constraints, stochastic parameters, rising treatment costs, and increased demand of outpatient oncology clinic services motivate the need for efficient appointment schedules and clinic operations. In this paper, we develop three mean-risk stochastic integer programming (SIP) models, referred to as SIP-CHEMO, for the problem of scheduling individual chemotherapy patient appointments and resources. These mean-risk models are presented and an algorithm is devised to improve computational speed. Computational results were conducted using a simulation model and results indicate that the risk-averse SIP-CHEMO model with the expected excess mean-risk measure can decrease patient waiting times and nurse overtime when compared to deterministic scheduling algorithms by 42 % and 27 %, respectively.
Badre, Bouchra; Serhier, Zineb; El Arabi, Samira
2014-01-01
Introduction Oral diseases may have an impact on quality of children's life. The presence of severe disability requires the use of care under general anesthesia (GA). However, because of the limited number of qualified health personnel, waiting time before intervention can be long. Aim: To evaluate the waiting time before dental care under general anesthesia for children with special needs in Morocco. Methods A retrospective cohort study was carried out in pediatric dentistry unit of the University Hospital of Casablanca. Data were collected from records of patients seen for the first time between 2006 and 2011. The waiting time was defined as the time between the date of the first consultation and intervention date. Results 127 children received dental care under general anesthesia, 57.5% were male and the average age was 9.2 (SD = 3.4). Decay was the most frequent reason for consultation (48%), followed by pain (32%). The average waiting time was 7.6 months (SD = 4.2 months). The average number of acts performed per patient was 13.5. Conclusion Waiting times were long, it is necessary to take measures to reduce delays and improve access to oral health care for this special population. PMID:25328594
ERIC Educational Resources Information Center
Andersson, Helle Wessel
2004-01-01
The present study addresses the question of equality of access, as it relates to waiting time for specialised mental health treatment for children and adolescents. The aim was to investigate whether demographic, clinical factors and service-related factors were associated with waiting time. Data was based on a documentation system in which all…
Discrimination in a universal health system: explaining socioeconomic waiting time gaps.
Johar, Meliyanni; Jones, Glenn; Keane, Micheal P; Savage, Elizabeth; Stavrunova, Olena
2013-01-01
One of the core goals of a universal health care system is to eliminate discrimination on the basis of socioeconomic status. We test for discrimination using patient waiting times for non-emergency treatment in public hospitals. Waiting time should reflect patients' clinical need with priority given to more urgent cases. Using data from Australia, we find evidence of prioritisation of the most socioeconomically advantaged patients at all quantiles of the waiting time distribution. These patients also benefit from variation in supply endowments. These results challenge the universal health system's core principle of equitable treatment. Copyright © 2012 Elsevier B.V. All rights reserved.
Waiting time as a competitive device: an example from general medical practice.
Iversen, Tor; Lurås, Hilde
2002-09-01
From a theoretical model we predict that only physicians with quality characteristics perceived as inferior by patients are willing to embark on waiting time reductions. Because of variation in these quality characteristics among physicians, market equilibrium is likely to show a range of waiting times for physician services. This hypothesis is supported by results from a study of Norwegian general practitioners. Since the waiting time offered by a physician influences the number of patient-initiated consultations, a policy implication of our study is that the distinction between patient-initiated and physician-initiated consultations may be less clear-cut than often assumed in the literature.
Are seismic waiting time distributions universal?
NASA Astrophysics Data System (ADS)
Davidsen, Jörn; Goltz, Christian
2004-11-01
We show that seismic waiting time distributions in California and Iceland have many features in common as, for example, a power-law decay with exponent α ~ 1.1 for intermediate and with exponent γ ~ 0.6 for short waiting times. While the transition point between these two regimes scales proportionally with the size of the considered area, the full distribution is not universal and depends in a non-trivial way on the geological area under consideration and its size. This is due to the spatial distribution of epicenters which does not form a simple mono-fractal. Yet, the dependence of the waiting time distributions on the threshold magnitude seems to be universal.
Impact of Lean on patient cycle and waiting times at a rural district hospital in KwaZulu-Natal.
Naidoo, Logandran; Mahomed, Ozayr H
2016-07-26
Prolonged waiting time is a source of patient dissatisfaction with health care and is negatively associated with patient satisfaction. Prolonged waiting times in many district hospitals result in many dissatisfied patients, overworked and frustrated staff, and poor quality of care because of the perceived increased workload. The aim of the study was to determine the impact of Lean principles techniques, and tools on the operational efficiency in the outpatient department (OPD) of a rural district hospital. The study was conducted at the Catherine Booth Hospital (CBH) - a rural district hospital in KwaZulu-Natal, South Africa. This was an action research study with pre-, intermediate-, and post-implementation assessments. Cycle and waiting times were measured by direct observation on two occasions before, approximately two-weekly during, and on two occasions after Lean implementation. A standardised data collection tool was completed by the researcher at each of the six key service nodes in the OPD to capture the waiting times and cycle times. All six service nodes showed a reduction in cycle times and waiting times between the baseline assessment and post-Lean implementation measurement. Significant reduction was achieved in cycle times (27%; p < 0.05) and waiting times (from 11.93 to 10 min; p = 0.03) at the Investigations node. Although the target reduction was not achieved for the Consulting Room node, there was a significant reduction in waiting times from 80.95 to 74.43 min, (p < 0.001). The average efficiency increased from 16.35% (baseline) to 20.13% (post-intervention). The application of Lean principles, tools and techniques provides hospital managers with an evidence-based management approach to resolving problems and improving quality indicators.
Impact of animal-assisted therapy for outpatients with fibromyalgia.
Marcus, Dawn A; Bernstein, Cheryl D; Constantin, Janet M; Kunkel, Frank A; Breuer, Paula; Hanlon, Raymond B
2013-01-01
Animal-assisted therapy using dogs trained to be calm and provide comfort to strangers has been used as a complementary therapy for a range of medical conditions. This study was designed to evaluate the effects of brief therapy dog visits for fibromyalgia patients attending a tertiary outpatient pain management facility compared with time spent in a waiting room. Open label with waiting room control. Tertiary care, university-based, outpatient pain management clinic. A convenience sample of fibromyalgia patients was obtained through advertisements posted in the clinic. Participants were able to spend clinic waiting time with a certified therapy dog instead of waiting in the outpatient waiting area. When the therapy dog was not available, individuals remained in the waiting area. OUTCOME MEASURES.: Self-reported pain, fatigue, and emotional distress were recorded using 11-point numeric rating scales before and after the therapy dog visit or waiting room time. Data were evaluated from 106 therapy dog visits and 49 waiting room controls, with no significant between-group demographic differences in participants. Average intervention duration was 12 minutes for the therapy dog visit and 17 minutes for the waiting room control. Significant improvements were reported for pain, mood, and other measures of distress among patients after the therapy dog visit, but not the waiting room control. Clinically meaningful pain relief (≥2 points pain severity reduction) occurred in 34% after the therapy dog visit and 4% in the waiting room control. Outcome was not affected by the presence of comorbid anxiety or depression. Brief therapy dog visits may provide a valuable complementary therapy for fibromyalgia outpatients. Wiley Periodicals, Inc.
Sobolev, Boris G; Kuramoto, Lisa; Levy, Adrian R; Hayden, Robert
2006-08-24
In deciding where to undergo coronary-artery bypass grafting, the length of surgical wait lists is often the only information available to cardiologists and their patients. Our objective was to compare the cumulative incidence for death on the wait list according to the length of wait lists at the time of registration for the operation. The study cohort included 8966 patients who registered to undergo isolated coronary-artery bypass grafting (82.4% men; 71.9% semi-urgent; 22.4% non-urgent). The patients were categorized according to wait-list clearance time at registration: either "1 month or less" or "more than 1 month". Cumulative incidence for wait-list death was compared between the groups, and the significance of difference was tested by means of regression models. Urgent patients never registered on a wait list with a clearance time of more than 1 month. Semi-urgent patients registered on shorter wait lists more often than non-urgent patients (79.1% vs. 44.7%). In semi-urgent and non-urgent patients, the observed proportion of wait-list deaths by 52 weeks was lower in category "1 month or less" than in category "more than 1 month" (0.8% [49 deaths] vs. 1.6% [39 deaths], P < 0.005). After adjustment, the odds of death before surgery were 64% higher in patients on longer lists, odds ratio [OR] = 1.64 (95% confidence interval [CI] 1.02-2.63). The observed death rate was higher in category "more than 1 month" than in category "1 month or less", 0.79 (95%CI 0.54-1.04) vs. 0.58 (95% CI 0.42-0.74) per 1000 patient-weeks, the adjusted OR = 1.60 (95%CI 1.01-2.53). Longer wait times (log-rank test = 266.4, P < 0.001) and higher death rates contributed to a higher cumulative incidence for death on the wait list with a clearance time of more than 1 month. Long wait lists for coronary-artery bypass grafting are associated with increased probability that a patient dies before surgery. Physicians who advise patients where to undergo cardiac revascularization should consider the risk of pre-surgical death that is associated with the length of a surgical wait list.
Haghighinejad, Hourvash Akbari; Kharazmi, Erfan; Hatam, Nahid; Yousefi, Sedigheh; Hesami, Seyed Ali; Danaei, Mina; Askarian, Mehrdad
2016-01-01
Background: Hospital emergencies have an essential role in health care systems. In the last decade, developed countries have paid great attention to overcrowding crisis in emergency departments. Simulation analysis of complex models for which conditions will change over time is much more effective than analytical solutions and emergency department (ED) is one of the most complex models for analysis. This study aimed to determine the number of patients who are waiting and waiting time in emergency department services in an Iranian hospital ED and to propose scenarios to reduce its queue and waiting time. Methods: This is a cross-sectional study in which simulation software (Arena, version 14) was used. The input information was extracted from the hospital database as well as through sampling. The objective was to evaluate the response variables of waiting time, number waiting and utilization of each server and test the three scenarios to improve them. Results: Running the models for 30 days revealed that a total of 4088 patients left the ED after being served and 1238 patients waited in the queue for admission in the ED bed area at end of the run (actually these patients received services out of their defined capacity). The first scenario result in the number of beds had to be increased from 81 to179 in order that the number waiting of the “bed area” server become almost zero. The second scenario which attempted to limit hospitalization time in the ED bed area to the third quartile of the serving time distribution could decrease the number waiting to 586 patients. Conclusion: Doubling the bed capacity in the emergency department and consequently other resources and capacity appropriately can solve the problem. This includes bed capacity requirement for both critically ill and less critically ill patients. Classification of ED internal sections based on severity of illness instead of medical specialty is another solution. PMID:26793727
Kasymjanova, G; Small, D; Cohen, V; Jagoe, R T; Batist, G; Sateren, W; Ernst, P; Pepe, C; Sakr, L; Agulnik, J
2017-10-01
Lung cancer continues to be one of the most common cancers in Canada, with approximately 28,400 new cases diagnosed each year. Although timely care can contribute substantially to quality of life for patients, it remains unclear whether it also improves patient outcomes. In this work, we used a set of quality indicators that aim to describe the quality of care in lung cancer patients. We assessed adherence with existing guidelines for timeliness of lung cancer care and concordance with existing standards of treatment, and we examined the association between timeliness of care and lung cancer survival. Patients with lung cancer diagnosed between 2010 and 2015 were identified from the Pulmonary Division Lung Cancer Registry at our centre. We demonstrated that the interdisciplinary pulmonary oncology service successfully treated most of its patients within the recommended wait times. However, there is still work to be done to decrease variation in wait time. Our results demonstrate a significant association between wait time and survival, supporting the need for clinicians to optimize the patient care trajectory. It would be helpful for Canadian clinicians treating patients with lung cancer to have wait time guidelines for all treatment modalities, together with standard definitions for all time intervals. Any reductions in wait times should be balanced against the need for thorough investigation before initiating treatment. We believe that our unique model of care leads to an acceleration of diagnostic steps. Avoiding any delay associated with referral to a medical oncologist for treatment could be an acceptable strategy with respect to reducing wait time.
Impact of waiting time on the quality of life of patients awaiting coronary artery bypass grafting.
Sampalis, J; Boukas, S; Liberman, M; Reid, T; Dupuis, G
2001-08-21
A lack of resources has created waiting lists for many elective surgical procedures within Canada's universal health care system. Coronary artery bypass grafting (CABG) for the treatment of atherosclerotic ischemic heart disease is one of these affected surgical procedures. We studied the impact of waiting times on the quality of life of patients awaiting CABG. A prospective cohort of 266 patients from 3 hospitals in Montreal was used. Patients who gave informed consent were followed from the time they were registered for CABG until 6 months after surgery; recruitment began in November 1993, and the last follow-up was completed in July 1995. Patient groups were classified according to the duration of the wait for CABG (< or = 97 days or > 97 days). We measured the following outcomes: quality of life (using the Medical Outcomes Study 36-item Short Form [SF-36]), incidence of chest pain (using the New York Heart Association angina classification), frequency of symptoms (using the Cardiac Symptom Inventory) and rates of complications and death before and after surgery. There were no differences in quality of life at baseline between the 2 groups. Immediately before surgery, compared with patients who waited 97 days or less, those who waited longer had significantly reduced physical functioning (change from baseline SF-36 score 0 v. -4 respectively, p = 0.001), vitality (change from baseline score -0.1 v. -1.3, p = 0.01), social functioning (change from baseline score 0.4 v. -0.4, p = 0.03) and general health (change from baseline score 1.1 v. -1.7, p = 0.001). At 6 months after surgery, compared with patients who waited 97 days or less for CABG, those who waited longer had reduced physical functioning (change from baseline SF-36 score 4.0 v. -0.1 respectively, p = 0.001), physical role (change from baseline score 0.8 v. 0.0, p = 0.001), vitality (change from baseline score 2.2 v. 0.9, p = 0.001), mental health (change from baseline score 1.2 v. 0.0, p = 0.001) and general health (change from baseline score 1.8 v. -0.3, p = 0.001). The incidence of postoperative adverse events was significantly greater among the patients with longer waits for CABG than among those with shorter waits (32 v. 14 events respectively, p = 0.005). Longer waits before CABG were associated with an increased likelihood of not returning to work after surgery (p = 0.08): 10 (53%) of the 19 patients with longer waiting times remained employed after CABG, as compared with 17 (85%) of the 20 with shorter waiting times. The significant decrease in physical and social functioning, both before and after surgery, for patients waiting more than 3 months for CABG is an important observation. Longer waiting times were also associated with increased postoperative adverse events. By decreasing waiting times for CABG, we may improve patients' quality of life and decrease the psychological morbidity associated with CABG.
[Improving the CMP appointment waiting time for children and adolescents].
Cani, Pascale
2014-01-01
The increasing activity of mental health centres for children and adolescents and longer waiting times in obtaining a first appointment have led an area of child psychiatry to question the organisation of new consultation applications. Two CMP in the sector had a waiting period of over 40 days for half of the patients. Two improvement actions were implemented:the implementation of organisation and reception nurses and the development of a new applications management process. The evaluation after one year showed a decrease of half of the appointment waiting time without changing the non showed up rate.
NASA Astrophysics Data System (ADS)
Liang, Yingjie; Chen, Wen
2018-04-01
The mean squared displacement (MSD) of the traditional ultraslow diffusion is a logarithmic function of time. Recently, the continuous time random walk model is employed to characterize this ultraslow diffusion dynamics by connecting the heavy-tailed logarithmic function and its variation as the asymptotical waiting time density. In this study we investigate the limiting waiting time density of a general ultraslow diffusion model via the inverse Mittag-Leffler function, whose special case includes the traditional logarithmic ultraslow diffusion model. The MSD of the general ultraslow diffusion model is analytically derived as an inverse Mittag-Leffler function, and is observed to increase even more slowly than that of the logarithmic function model. The occurrence of very long waiting time in the case of the inverse Mittag-Leffler function has the largest probability compared with the power law model and the logarithmic function model. The Monte Carlo simulations of one dimensional sample path of a single particle are also performed. The results show that the inverse Mittag-Leffler waiting time density is effective in depicting the general ultraslow random motion.
Inverse statistics in the foreign exchange market
NASA Astrophysics Data System (ADS)
Jensen, M. H.; Johansen, A.; Petroni, F.; Simonsen, I.
2004-09-01
We investigate intra-day foreign exchange (FX) time series using the inverse statistic analysis developed by Simonsen et al. (Eur. Phys. J. 27 (2002) 583) and Jensen et al. (Physica A 324 (2003) 338). Specifically, we study the time-averaged distributions of waiting times needed to obtain a certain increase (decrease) ρ in the price of an investment. The analysis is performed for the Deutsch Mark (DM) against the US for the full year of 1998, but similar results are obtained for the Japanese Yen against the US. With high statistical significance, the presence of “resonance peaks” in the waiting time distributions is established. Such peaks are a consequence of the trading habits of the market participants as they are not present in the corresponding tick (business) waiting time distributions. Furthermore, a new stylized fact, is observed for the (normalized) waiting time distribution in the form of a power law Pdf. This result is achieved by rescaling of the physical waiting time by the corresponding tick time thereby partially removing scale-dependent features of the market activity.
ERIC Educational Resources Information Center
Pond, Marlene R.; Newman, Isadore
The effects of wait-time, the pause following a teacher question and the pause after a student response, on the length and number of student responses were analyzed at different cognitive levels. Data were obtained from 95 students in grade 4 and from 5 teachers using a wait-time of 5 seconds. Four oral discussion sessions by teachers and students…
Waiting Time: The De-Subjectification of Children in Danish Asylum Centres
ERIC Educational Resources Information Center
Vitus, Kathrine
2010-01-01
This article analyses the relationship between time and subjectification, focusing on the temporal structures created within Danish asylum centres and politics, and on children's experiences of and reactions to open-ended waiting. Such waiting leads to existential boredom which manifests in the children as restlessness, fatigue and despair. The…
[Reducing patient waiting time for the outpatient phlebotomy service using six sigma].
Kim, Yu Kyung; Song, Kyung Eun; Lee, Won Kil
2009-04-01
One of the challenging issues of the outpatient phlebotomy services at most hospitals is that patients have a long wait. The outpatient phlebotomy team of Kyungpook National University Hospital applied six sigma breakthrough methodologies to reduce the patient waiting time. The DMAIC (Define, Measure, Analyze, Improve, and Control) model was employed to approach the project. Two hundred patients visiting the outpatient phlebotomy section were asked to answer the questionnaires at inception of the study to ascertain root causes. After correction, we surveyed 285 patients for same questionnaires again to follow-up the effects. A defect was defined as extending patient waiting time so long and at the beginning of the project, the performance level was 2.61 sigma. Using fishbone diagram, all the possible reasons for extending patient waiting time were captured, and among them, 16 causes were proven to be statistically significant. Improvement plans including a new receptionist, automatic specimen transport system, and adding one phlebotomist were put into practice. As a result, the number of patients waited more than 5 min significantly decreased, and the performance level reached 3.0 sigma in December 2007 and finally 3.35 sigma in July 2008. Applying the six sigma, the performance level of waiting times for blood drawing exceeding five minutes were improved from 2.61 sigma to 3.35 sigma.
Not all waits are equal: an exploratory investigation of emergency care patient pathways.
Swancutt, Dawn; Joel-Edgar, Sian; Allen, Michael; Thomas, Daniel; Brant, Heather; Benger, Jonathan; Byng, Richard; Pinkney, Jonathan
2017-06-24
Increasing pressure in the United Kingdom (UK) urgent care system has led to Emergency Departments (EDs) failing to meet the national requirement that 95% of patients are admitted, discharged or transferred within 4-h of arrival. Despite the target being the same for all acute hospitals, individual Trusts organise their services in different ways. The impact of this variation on patient journey time and waiting is unknown. Our study aimed to apply the Lean technique of Value Stream Mapping (VSM) to investigate care processes and delays in patient journeys at four contrasting hospitals. VSM timing data were collected for patients accessing acute care at four hospitals in South West England. Data were categorised according to waits and activities, which were compared across sites to identify variations in practice from the patient viewpoint. We included Public and Patient Involvement (PPI) to fully interpret our findings; observations and initial findings were considered in a PPI workshop. One hundred eight patients were recruited, comprising 25,432 min of patient time containing 4098 episodes of care or waiting. The median patient journey was 223 min (3 h, 43 min); just within the 4-h target. Although total patient journey times were similar between sites, the stage where the greatest proportion of waiting occurred varied. Reasons for waiting were dominated by waits for beds, investigations or results to be available. From our sample we observed that EDs without a discharge/clinical decision area exhibited a greater proportion of waiting time following an admission or discharge decision. PPI interpretation indicated that patients who experience waits at the beginning of their journey feel more anxious because they are 'not in the system yet'. The novel application of VSM analysis across different hospitals, coupled with PPI interpretation, provides important insight into the impact of care provision on patient experience. Measures that could reduce patient waiting include automatic notification of test results, and the option of discharge/clinical decision areas for patients awaiting results or departure. To enhance patient experience, good communication with patients and relatives about reasons for waits is essential.
Stover, Pamela R; Harpin, Scott
2015-12-01
Limited capacity in a psychiatric unit contributes to long emergency department (ED) admission wait times. Regulatory and accrediting agencies urge hospitals nationally to improve patient flow for better access to care for all types of patients. The purpose of the current study was to decrease psychiatric admission wait time from 10.5 to 8 hours and increase the proportion of patients discharged by 11 a.m. from 20% to 50%. The current study compared pre- and post-intervention data. Plan-Do-Study-Act cycles aimed to improve discharge processes and timeliness through initiation of new practices. Admission wait time improved to an average of 5.1 hours (t = 3.87, p = 0.006). The proportion of discharges occurring by 11 a.m. increased to 46% (odds ratio = 3.42, p < 0.0001). Improving discharge planning processes and timeliness in a psychiatric unit significantly decreased admission wait time from the ED, improving access to psychiatric care. Copyright 2015, SLACK Incorporated.
Intelligent elevator management system using image processing
NASA Astrophysics Data System (ADS)
Narayanan, H. Sai; Karunamurthy, Vignesh; Kumar, R. Barath
2015-03-01
In the modern era, the increase in the number of shopping malls and industrial building has led to an exponential increase in the usage of elevator systems. Thus there is an increased need for an effective control system to manage the elevator system. This paper is aimed at introducing an effective method to control the movement of the elevators by considering various cases where in the location of the person is found and the elevators are controlled based on various conditions like Load, proximity etc... This method continuously monitors the weight limit of each elevator while also making use of image processing to determine the number of persons waiting for an elevator in respective floors. Canny edge detection technique is used to find out the number of persons waiting for an elevator. Hence the algorithm takes a lot of cases into account and locates the correct elevator to service the respective persons waiting in different floors.
Modeling and simulation of M/M/c queuing pharmacy system with adjustable parameters
NASA Astrophysics Data System (ADS)
Rashida, A. R.; Fadzli, Mohammad; Ibrahim, Safwati; Goh, Siti Rohana
2016-02-01
This paper studies a discrete event simulation (DES) as a computer based modelling that imitates a real system of pharmacy unit. M/M/c queuing theo is used to model and analyse the characteristic of queuing system at the pharmacy unit of Hospital Tuanku Fauziah, Kangar in Perlis, Malaysia. The input of this model is based on statistical data collected for 20 working days in June 2014. Currently, patient waiting time of pharmacy unit is more than 15 minutes. The actual operation of the pharmacy unit is a mixed queuing server with M/M/2 queuing model where the pharmacist is referred as the server parameters. DES approach and ProModel simulation software is used to simulate the queuing model and to propose the improvement for queuing system at this pharmacy system. Waiting time for each server is analysed and found out that Counter 3 and 4 has the highest waiting time which is 16.98 and 16.73 minutes. Three scenarios; M/M/3, M/M/4 and M/M/5 are simulated and waiting time for actual queuing model and experimental queuing model are compared. The simulation results show that by adding the server (pharmacist), it will reduce patient waiting time to a reasonable improvement. Almost 50% average patient waiting time is reduced when one pharmacist is added to the counter. However, it is not necessary to fully utilize all counters because eventhough M/M/4 and M/M/5 produced more reduction in patient waiting time, but it is ineffective since Counter 5 is rarely used.
Waiting time for cataract surgery and its influence on patient attitudes.
Chan, Frank Wan-kin; Fan, Alex Hoi; Wong, Fiona Yan-yan; Lam, Philip Tsze-ho; Yeoh, Eng-kiong; Yam, Carrie Ho-kwan; Griffiths, Sian; Lam, Dennis Shun-chiu; Congdon, Nathan
2009-08-01
To characterize willingness to pay for private operations and preferred waiting time among patients awaiting cataract surgery in Hong Kong. This was a cross-sectional survey. Subjects randomly selected from cataract surgical waiting lists in Hong Kong (n = 467) underwent a telephone interview based on a structured, validated questionnaire. Data were collected on private insurance coverage, preferred waiting time, amount willing to pay for surgery, and self-reported visual function and health status. Among 300 subjects completing the interview, 144 (48.2%) were 76 years of age or older, 177 (59%) were women, and mean time waiting for surgery was 17 +/- 15 months. Among 220 subjects (73.3%) willing to pay anything for surgery, the mean amount was US$552 +/- 443. With adjustment for age, education, and monthly household income, subjects willing to pay anything were less willing to wait 12 months for surgery (OR = 4.34; P = 0.002), more likely to know someone having had cataract surgery (OR = 2.20; P = 0.03), and more likely to use their own savings to pay for the surgery (OR = 2.21; P = 0.04). Subjects considering private cataract surgery, knowing people who have had cataract surgery, using nongovernment sources to pay for surgery, and having lower visual function were willing to pay more. Many patients wait significant periods for cataract surgery in Hong Kong, and are willing to pay substantial amounts for private operations. These results may have implications for other countries with cataract waiting lists.
Emergency medicine: an operations management view.
Soremekun, Olan A; Terwiesch, Christian; Pines, Jesse M
2011-12-01
Operations management (OM) is the science of understanding and improving business processes. For the emergency department (ED), OM principles can be used to reduce and alleviate the effects of crowding. A fundamental principle of OM is the waiting time formula, which has clear implications in the ED given that waiting time is fundamental to patient-centered emergency care. The waiting time formula consists of the activity time (how long it takes to complete a process), the utilization rate (the proportion of time a particular resource such a staff is working), and two measures of variation: the variation in patient interarrival times and the variation in patient processing times. Understanding the waiting time formula is important because it presents the fundamental parameters that can be managed to reduce waiting times and length of stay. An additional useful OM principle that is applicable to the ED is the efficient frontier. The efficient frontier compares the performance of EDs with respect to two dimensions: responsiveness (i.e., 1/wait time) and utilization rates. Some EDs may be "on the frontier," maximizing their responsiveness at their given utilization rates. However, most EDs likely have opportunities to move toward the frontier. Increasing capacity is a movement along the frontier and to truly move toward the frontier (i.e., improving responsiveness at a fixed capacity), we articulate three possible options: eliminating waste, reducing variability, or increasing flexibility. When conceptualizing ED crowding interventions, these are the major strategies to consider. © 2011 by the Society for Academic Emergency Medicine.
Fairness in the coronary angiography queue.
Alter, D A; Basinski, A S; Cohen, E A; Naylor, C D
1999-10-05
Since waiting lists for coronary angiography are generally managed without explicit queuing criteria, patients may not receive priority on the basis of clinical acuity. The objective of this study was to examine clinical and nonclinical determinants of the length of time patients wait for coronary angiography. In this single-centre prospective cohort study conducted in the autumn of 1997, 357 consecutive patients were followed from initial triage until a coronary angiography was performed or an adverse cardiac event occurred. The referring physicians' hospital affiliation (physicians at Sunnybrook & Women's College Health Sciences Centre, those who practice at another centre but perform angiography at Sunnybrook and those with no previous association with Sunnybrook) was used to compare processes of care. A clinical urgency rating scale was used to assign a recommended maximum waiting time (RMWT) to each patient retrospectively, but this was not used in the queuing process. RMWTs and actual waiting times for patients in the 3 referral groups were compared; the influence clinical and nonclinical variables had on the actual length of time patients waited for coronary angiography was assessed; and possible predictors of adverse events were examined. Of 357 patients referred to Sunnybrook, 22 (6.2%) experienced adverse events while in the queue. Among those who remained, 308 (91.9%) were in need of coronary angiography; 201 (60.0%) of those patients received one within the RMWT. The length of time to angiography was influenced by clinical characteristics similar to those specified on the urgency rating scale, leading to a moderate agreement between actual waiting times and RMWTs (kappa = 0.53). However, physician affiliation was a highly significant (p < 0.001) and independent predictor of waiting time. Whereas 45.6% of the variation in waiting time was explained by all clinical factors combined, 9.3% of the variation was explained by physician affiliation alone. Informal queuing practices for coronary angiography do reflect clinical acuity, but they are also influenced by nonclinical factors, such as the nature of the physicians' association with the catheterization facility.
Bishai, D M; Lang, H C
2000-03-01
We estimate demand curves for a one month reduction in waiting time for cataract surgery based on survey data collected in 1992 in Manitoba, Barcelona, and Denmark. Patients answered, "Would you be willing to pay [Bid, B] to reduce your waiting time for cataract surgery to less than one month?" Controlling for SES and visual status, Barcelonan patients have greater WTP for shortened waiting time than the Danes and Manitobans. We estimate the value (in 1992 $) of lost consumer surplus due to the cataract surgery queue at $128 per patient in Manitoba, $160 in Denmark, and $243 in Barcelona.
Kidd, Celeste; Palmeri, Holly; Aslin, Richard N
2013-01-01
Children are notoriously bad at delaying gratification to achieve later, greater rewards (e.g., Piaget, 1970)-and some are worse at waiting than others. Individual differences in the ability-to-wait have been attributed to self-control, in part because of evidence that long-delayers are more successful in later life (e.g., Shoda, Mischel, & Peake, 1990). Here we provide evidence that, in addition to self-control, children's wait-times are modulated by an implicit, rational decision-making process that considers environmental reliability. We tested children (M=4;6, N=28) using a classic paradigm-the marshmallow task (Mischel, 1974)-in an environment demonstrated to be either unreliable or reliable. Children in the reliable condition waited significantly longer than those in the unreliable condition (p<0.0005), suggesting that children's wait-times reflected reasoned beliefs about whether waiting would ultimately pay off. Thus, wait-times on sustained delay-of-gratification tasks (e.g., the marshmallow task) may not only reflect differences in self-control abilities, but also beliefs about the stability of the world. Copyright © 2012 Elsevier B.V. All rights reserved.
On-demand high-capacity ride-sharing via dynamic trip-vehicle assignment
Alonso-Mora, Javier; Samaranayake, Samitha; Wallar, Alex; Frazzoli, Emilio; Rus, Daniela
2017-01-01
Ride-sharing services are transforming urban mobility by providing timely and convenient transportation to anybody, anywhere, and anytime. These services present enormous potential for positive societal impacts with respect to pollution, energy consumption, congestion, etc. Current mathematical models, however, do not fully address the potential of ride-sharing. Recently, a large-scale study highlighted some of the benefits of car pooling but was limited to static routes with two riders per vehicle (optimally) or three (with heuristics). We present a more general mathematical model for real-time high-capacity ride-sharing that (i) scales to large numbers of passengers and trips and (ii) dynamically generates optimal routes with respect to online demand and vehicle locations. The algorithm starts from a greedy assignment and improves it through a constrained optimization, quickly returning solutions of good quality and converging to the optimal assignment over time. We quantify experimentally the tradeoff between fleet size, capacity, waiting time, travel delay, and operational costs for low- to medium-capacity vehicles, such as taxis and van shuttles. The algorithm is validated with ∼3 million rides extracted from the New York City taxicab public dataset. Our experimental study considers ride-sharing with rider capacity of up to 10 simultaneous passengers per vehicle. The algorithm applies to fleets of autonomous vehicles and also incorporates rebalancing of idling vehicles to areas of high demand. This framework is general and can be used for many real-time multivehicle, multitask assignment problems. PMID:28049820
On-demand high-capacity ride-sharing via dynamic trip-vehicle assignment.
Alonso-Mora, Javier; Samaranayake, Samitha; Wallar, Alex; Frazzoli, Emilio; Rus, Daniela
2017-01-17
Ride-sharing services are transforming urban mobility by providing timely and convenient transportation to anybody, anywhere, and anytime. These services present enormous potential for positive societal impacts with respect to pollution, energy consumption, congestion, etc. Current mathematical models, however, do not fully address the potential of ride-sharing. Recently, a large-scale study highlighted some of the benefits of car pooling but was limited to static routes with two riders per vehicle (optimally) or three (with heuristics). We present a more general mathematical model for real-time high-capacity ride-sharing that (i) scales to large numbers of passengers and trips and (ii) dynamically generates optimal routes with respect to online demand and vehicle locations. The algorithm starts from a greedy assignment and improves it through a constrained optimization, quickly returning solutions of good quality and converging to the optimal assignment over time. We quantify experimentally the tradeoff between fleet size, capacity, waiting time, travel delay, and operational costs for low- to medium-capacity vehicles, such as taxis and van shuttles. The algorithm is validated with ∼3 million rides extracted from the New York City taxicab public dataset. Our experimental study considers ride-sharing with rider capacity of up to 10 simultaneous passengers per vehicle. The algorithm applies to fleets of autonomous vehicles and also incorporates rebalancing of idling vehicles to areas of high demand. This framework is general and can be used for many real-time multivehicle, multitask assignment problems.
An Integrated Model of Patient and Staff Satisfaction Using Queuing Theory
Mousavi, Ali; Clarkson, P. John; Young, Terry
2015-01-01
This paper investigates the connection between patient satisfaction, waiting time, staff satisfaction, and service time. It uses a variety of models to enable improvement against experiential and operational health service goals. Patient satisfaction levels are estimated using a model based on waiting (waiting times). Staff satisfaction levels are estimated using a model based on the time spent with patients (service time). An integrated model of patient and staff satisfaction, the effective satisfaction level model, is then proposed (using queuing theory). This links patient satisfaction, waiting time, staff satisfaction, and service time, connecting two important concepts, namely, experience and efficiency in care delivery and leading to a more holistic approach in designing and managing health services. The proposed model will enable healthcare systems analysts to objectively and directly relate elements of service quality to capacity planning. Moreover, as an instrument used jointly by healthcare commissioners and providers, it affords the prospect of better resource allocation. PMID:27170899
An Integrated Model of Patient and Staff Satisfaction Using Queuing Theory.
Komashie, Alexander; Mousavi, Ali; Clarkson, P John; Young, Terry
2015-01-01
This paper investigates the connection between patient satisfaction, waiting time, staff satisfaction, and service time. It uses a variety of models to enable improvement against experiential and operational health service goals. Patient satisfaction levels are estimated using a model based on waiting (waiting times). Staff satisfaction levels are estimated using a model based on the time spent with patients (service time). An integrated model of patient and staff satisfaction, the effective satisfaction level model, is then proposed (using queuing theory). This links patient satisfaction, waiting time, staff satisfaction, and service time, connecting two important concepts, namely, experience and efficiency in care delivery and leading to a more holistic approach in designing and managing health services. The proposed model will enable healthcare systems analysts to objectively and directly relate elements of service quality to capacity planning. Moreover, as an instrument used jointly by healthcare commissioners and providers, it affords the prospect of better resource allocation.
Looking for Lithotripsy: Accessibility and Portability of Canadian Healthcare
Piggott, Katrina L.; Bell, Chaim M.
2013-01-01
Background: Extracorporeal shock wave lithotripsy (ESWL) is a definitive, ambulatory and non-invasive modality for treating kidney stones. ESWL is not available in all urban centres and many Canadians must either travel, sometimes out of province, or wait to have this procedure performed. We sought to evaluate the variability in access to ESWL treatment. Method: We compiled a comprehensive list of ESWL centres in Canada and contacted all centres in 2011 to assess their wait times, out-of-province patient fees, and roles and responsibilities of the referring physician. Results: We contacted all 23 ESWL facilities across Canada (100% response rate). Wait times for elective ESWL procedures ranged from one day to over one year, with a mean of 8.4 weeks (SD, 16.76 weeks). No centres refused out-of-province patients, although five discouraged travel to their centre owing to their prolonged wait times. No facilities charged extra fees for out-of-province patients. Ten (43%) facilities required a secondary consultation by a urolo-gist at the centre before booking. Twelve (52%) of the centres indicated the waiting time could be shortened if the referring physician were to advocate on the patient's behalf. Contact was repeated one year later in 2012 with five centres, and the results were similar. Interpretation: There is marked variation in wait times across Canada for ESWL but there are few barriers to care. Patients' waits may be shortened by physician advocacy. PMID:24359718
Rationing in the emergency department: the good, the bad, and the unacceptable.
Cross, E; Goodacre, S; O'Cathain, A; Arnold, J
2005-03-01
Waiting times in emergency departments (EDs) are an important government priority. Although substantial efforts are currently being made to reduce waiting times, little attention has been paid to the patients' view. We used qualitative methods to explore patients' perspectives on waiting times and other approaches to rationing and prioritisation. Face to face, in depth, qualitative interviews (n = 11) explored how patients valued waiting times for non-urgent ED care. The framework approach (identifying a thematic framework through repeated re-reading) was used to analyse transcripts. Interviewees found some forms of rationing and prioritisation acceptable. They expected rationing by delay, but required explanations or information on the reason for their wait. They valued prioritisation by triage (rationing by selection) and thought that this role could be expanded for the re-direction of non-urgent patients elsewhere (rationing by deflection). Interviewees were mainly unwilling or unable to engage in prioritisation of different types of patients, openly prioritising only those with obvious clinical need, and children. However, some interviewees were willing to ration implicitly, labelling some attenders as inappropriate, such as those causing a nuisance. Others felt it was unacceptable to blame "inappropriate" attenders, as their attendance may relate to lack of information or awareness of service use. Explicit rationing between services was not acceptable, although some believed there were more important priorities for NHS resources than ED waiting times. Interviewees disagreed with the hypothetical notion of paying to be seen more quickly in the ED (rationing by charging). Interviewees expected to wait and accepted the need for prioritisation, although they were reluctant to engage in judgements regarding prioritisation. They supported the re-direction of patients with certain non-urgent complaints. However, they perceived a need for more explanation and information about their wait, the system, and alternative services.
Konerding, Uwe; Bowen, Tom; Elkhuizen, Sylvia G; Faubel, Raquel; Forte, Paul; Karampli, Eleftheria; Mahdavi, Mahdi; Malmström, Tomi; Pavi, Elpida; Torkki, Paulus
2017-04-01
The effects of travel distance and travel time to the primary diabetes care provider and waiting time in the practice on health-related quality of life (HRQoL) of patients with type 2 diabetes are investigated. Survey data of 1313 persons with type 2 diabetes from six regions in England (274), Finland (163), Germany (254), Greece (165), the Netherlands (354), and Spain (103) were analyzed. Various multiple linear regression analyses with four different EQ-5D-3L indices (English, German, Dutch and Spanish index) as target variables, with travel distance, travel time, and waiting time in the practice as focal predictors and with control for study region, patient's gender, patient's age, patient's education, time since diagnosis, thoroughness of provider-patient communication were computed. Interactions of regions with the remaining five control variables and the three focal predictors were also tested. There are no interactions of regions with control variables or focal predictors. The indices decrease with increasing travel time to the provider and increasing waiting time in the provider's practice. HRQoL of patients with type 2 diabetes might be improved by decreasing travel time to the provider and waiting time in the provider's practice. Copyright © 2017 Elsevier B.V. All rights reserved.
Gjolaj, Lauren N; Gari, Gloria A; Olier-Pino, Angela I; Garcia, Juan D; Fernandez, Gustavo L
2014-11-01
Prolonged patient wait times in the outpatient oncology infusion unit indicated a need to streamline phlebotomy processes by using existing resources to decrease laboratory turnaround time and improve patient wait time. Using the DMAIC (define, measure, analyze, improve, control) method, a project to streamline phlebotomy processes within the outpatient oncology infusion unit in an academic Comprehensive Cancer Center known as the Comprehensive Treatment Unit (CTU) was completed. Laboratory turnaround time for patients who needed same-day lab and CTU services and wait time for all CTU patients was tracked for 9 weeks. During the pilot, the wait time from arrival to CTU to sitting in treatment area decreased by 17% for all patients treated in the CTU during the pilot. A total of 528 patients were seen at the CTU phlebotomy location, representing 16% of the total patients who received treatment in the CTU, with a mean turnaround time of 24 minutes compared with a baseline turnaround time of 51 minutes. Streamlining workflows and placing a phlebotomy station inside of the CTU decreased laboratory turnaround times by 53% for patients requiring same day lab and CTU services. The success of the pilot project prompted the team to make the station a permanent fixture. Copyright © 2014 by American Society of Clinical Oncology.
Herden, Uta; Grabhorn, Enke; Briem-Richter, Andrea; Ganschow, Rainer; Nashan, Björn; Fischer, Lutz
2014-09-01
Liver allocation in the Eurotransplant (ET) region has changed from a waiting time to an urgency-based system using the model of end-stage liver disease (MELD) score in 2006. To allow timely transplantation, pediatric recipients are allocated by an assigned pediatric MELD independent of severity of illness. Consequences for children listed at our center were evaluated by retrospective analysis of all primary pediatric liver transplantation (LTX) from deceased donors between 2002 and 2010 (110 LTX before/50 LTX after new allocation). Of 50 children transplanted in the MELD era, 17 (34%) underwent LTX with a high-urgent status that was real in five patients (median lab MELD 22, waiting time five d) and assigned in 12 patients (lab MELD 7, waiting time 35 d). Thirty-three children received a liver by their assigned pediatric MELD (lab MELD 15, waiting time 255 d). Waiting time in the two periods was similar, whereas the wait-list mortality decreased (from about four children/yr to about one child/yr). One- and three-yr patient survival showed no significant difference (94.5/97.7%; p = 0.385) as did one- and three-yr graft survival (80.7/75.2%; and 86.5/82%; p = 0.436 before/after). Introduction of a MELD-based allocation system in ET with assignment of a granted score for pediatric recipients has led to a clear priorization of children resulting in a low wait-list mortality and good clinical outcome. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Reading and Television Viewing Habits of American Adults during Time Spent in Waiting Rooms.
ERIC Educational Resources Information Center
Spirn, Sharon L.
In order to determine the reading and television viewing habits of American adults during time spent in waiting rooms, a study observed 100 adults waiting outside the Emergency Treatment Room of John F. Kennedy Hospital in Edison, New Jersey, over a four-week period. Results revealed that more of these adults chose to watch television as an…
Reward Sensitivity and Waiting Impulsivity: Shift towards Reward Valuation away from Action Control
Mechelmans, Daisy J; Strelchuk, Daniela; Doñamayor, Nuria; Banca, Paula; Robbins, Trevor W; Baek, Kwangyeol
2017-01-01
Abstract Background Impulsivity and reward expectancy are commonly interrelated. Waiting impulsivity, measured using the rodent 5-Choice Serial Reaction Time task, predicts compulsive cocaine seeking and sign (or cue) tracking. Here, we assess human waiting impulsivity using a novel translational task, the 4-Choice Serial Reaction Time task, and the relationship with reward cues. Methods Healthy volunteers (n=29) performed the monetary incentive delay task as a functional MRI study where subjects observe a cue predicting reward (cue) and wait to respond for high (£5), low (£1), or no reward. Waiting impulsivity was tested with the 4-Choice Serial Reaction Time task. Results For high reward prospects (£5, no reward), greater waiting impulsivity on the 4-CSRT correlated with greater medial orbitofrontal cortex and lower supplementary motor area activity to cues. In response to high reward cues, greater waiting impulsivity was associated with greater subthalamic nucleus connectivity with orbitofrontal cortex and greater subgenual cingulate connectivity with anterior insula, but decreased connectivity with regions implicated in action selection and preparation. Conclusion These findings highlight a shift towards regions implicated in reward valuation and a shift towards compulsivity away from higher level motor preparation and action selection and response. We highlight the role of reward sensitivity and impulsivity, mechanisms potentially linking human waiting impulsivity with incentive approach and compulsivity, theories highly relevant to disorders of addiction. PMID:29020291
Patient satisfaction with wait times at an emergency ophthalmology on-call service.
Chan, Brian J; Barbosa, Joshua; Moinul, Prima; Sivachandran, Nirojini; Donaldson, Laura; Zhao, Lily; Mullen, Sarah J; McLaughlin, Christopher R; Chaudhary, Varun
2018-04-01
To assess patient satisfaction with emergency ophthalmology care and determine the effect provision of anticipated appointment wait time has on scores. Single-centre, randomized control trial. Fifty patients triaged at the Hamilton Regional Eye Institute (HREI) from November 2015 to July 2016. Fifty patients triaged for next-day appointments at the HREI were randomly assigned to receive standard-of-care preappointment information or standard-of-care information in addition to an estimated appointment wait time. Patient satisfaction with care was assessed postvisit using the modified Judgements of Hospital Quality Questionnaire (JHQQ). In determining how informing patients of typical wait times influenced satisfaction, the Mann-Whitney U test was performed. As secondary study outcomes, we sought to determine patient satisfaction with the intervention material using the Fisher exact test and the effect that wait time, age, sex, education, mobility, and number of health care providers seen had on satisfaction scores using logistic regression analysis. The median JHQQ response was "very good" (4/5) and between "very good" and "excellent" (4.5/5) in the intervention and control arms, respectively. There was no difference in patient satisfaction between the cohorts (Mann-Whitney U = 297.00, p = 0.964). Logistic regression analysis demonstrated that wait times influenced patient satisfaction (OR = 0.919, 95% CI 0.864-0.978, p = 0.008). Of the intervention arm patients, 92.0% (N = 23) found the preappointment information useful, whereas only 12.5% (N = 3) of the control cohort patients noted the same (p < 0.001). Provision of anticipated wait time information to patients in an emergency on-call ophthalmology clinic did not influence satisfaction with care as captured by the JHQQ. Copyright © 2018 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.
Effect of socioeconomic deprivation on waiting time for cardiac surgery: retrospective cohort study
Pell, Jill P; Pell, Alastair C H; Norrie, John; Ford, Ian; Cobbe, Stuart M
2000-01-01
Objective To determine whether the priority given to patients referred for cardiac surgery is associated with socioeconomic status. Design Retrospective study with multivariate logistic regression analysis of the association between deprivation and classification of urgency with allowance for age, sex, and type of operation. Multivariate linear regression analysis was used to determine association between deprivation and waiting time within each category of urgency, with allowance for age, sex, and type of operation. Setting NHS waiting lists in Scotland. Participants 26 642 patients waiting for cardiac surgery, 1 January 1986 to 31 December 1997. Main outcome measures Deprivation as measured by Carstairs deprivation category. Time spent on NHS waiting list. Results Patients who were most deprived tended to be younger and were more likely to be female. Patients in deprivation categories 6 and 7 (most deprived) waited about three weeks longer for surgery than those in category 1 (mean difference 24 days, 95% confidence interval 15 to 32). Deprived patients had an odds ratio of 0.5 (0.46 to 0.61) for having their operations classified as urgent compared with the least deprived, after allowance for age, sex, and type of operation. When urgent and routine cases were considered separately, there was no significant difference in waiting times between the most and least deprived categories. Conclusions Socioeconomically deprived patients are thought to be more likely to develop coronary heart disease but are less likely to be investigated and offered surgery once it has developed. Such patients may be further disadvantaged by having to wait longer for surgery because of being given lower priority. PMID:10617517
Ramsey waits: allocating public health service resources when there is rationing by waiting.
Gravelle, Hugh; Siciliani, Luigi
2008-09-01
The optimal allocation of a public health care budget across treatments must take account of the way in which care is rationed within treatments since this will affect their marginal value. We investigate the optimal allocation rules for public health care systems where user charges are fixed and care is rationed by waiting. The optimal waiting time is higher for treatments with demands more elastic to waiting time, higher costs, lower charges, smaller marginal welfare loss from waiting by treated patients, and smaller marginal welfare losses from under-consumption of care. The results hold for a wide range of welfarist and non-welfarist objective functions and for systems in which there is also a private health care sector. They imply that allocation rules based purely on cost effectiveness ratios are suboptimal because they assume that there is no rationing within treatments.
A Model to Study: Cannibalization, FMC, and Customer Waiting Time
2002-02-01
4825 Mark Center Drive • Alexandria, Virginia 22311-1850 CRM D0005957.A2/Final February 2002 A Model to Study: Cannibalization, FMC, and Customer ...numerical example In this section, we will derive the relationship between cannibaliza- tion rates, customer waiting time (CWT) for needed spare parts... relationships between the FMC given by equation 1, the mean customer wait time for spare parts, denoted µ, and the 5. According to [19], not every part can be
Influence of Waiting Time on the Levitation Force Between a Permanent Magnet and a Superconductor
NASA Astrophysics Data System (ADS)
Zhang, Xing-Yi; Zhou, You-He; Zhou, Jun
This paper describes the experimental results of the levitation force of single-grained YBaCuO bulk superconductors preparing by the top-seeded melt-growth method with different waiting time tw below an NdFeB permanent magnet. It was found that waiting time has large effects on the zero-field-cooled (ZFC) and field-cooled (FC) levitation force, and the levitation force shows aging characteristics at the liquid nitrogen temperature.
Househ, Mowafa; Yunus, Faisel
2014-01-01
Saudi hospital emergency departments (ED) have suffered from long waiting times, which have led to a delay in emergency patient care. The increase in the population of Saudi Arabia is likely to further stretch the healthcare services due to overcrowding leading to decreased healthcare quality, long patient waits, patient dissatisfaction, ambulance diversions, decreased physician productivity, and increased frustration among medical staff. This will ultimately put patients at risk for poor health outcomes. Time is of the essence in emergencies and to get to an ED that has the shortest waiting time can mean life or death for a patient, especially in cases of stroke and myocardial infarction. In this paper, we present our work on the development of a mHealth Application - EDWaT - that will: provide patient flow information to the emergency medical services staff, help in quick routing of patients to the nearest hospital, and provide an opportunity for patients to review and rate the quality of care received at an ED, which will then be forwarded to ED services administrators. The quality ratings will help patients to choose between two EDs with the same waiting time and distance from their location. We anticipate that the use of EDWaT will help improve ED wait times and the quality of care provision in Saudi hospitals EDs.
Kittipittayakorn, Cholada; Ying, Kuo-Ching
2016-01-01
Many hospitals are currently paying more attention to patient satisfaction since it is an important service quality index. Many Asian countries' healthcare systems have a mixed-type registration, accepting both walk-in patients and scheduled patients. This complex registration system causes a long patient waiting time in outpatient clinics. Different approaches have been proposed to reduce the waiting time. This study uses the integration of discrete event simulation (DES) and agent-based simulation (ABS) to improve patient waiting time and is the first attempt to apply this approach to solve this key problem faced by orthopedic departments. From the data collected, patient behaviors are modeled and incorporated into a massive agent-based simulation. The proposed approach is an aid for analyzing and modifying orthopedic department processes, allows us to consider far more details, and provides more reliable results. After applying the proposed approach, the total waiting time of the orthopedic department fell from 1246.39 minutes to 847.21 minutes. Thus, using the correct simulation model significantly reduces patient waiting time in an orthopedic department.
Kittipittayakorn, Cholada
2016-01-01
Many hospitals are currently paying more attention to patient satisfaction since it is an important service quality index. Many Asian countries' healthcare systems have a mixed-type registration, accepting both walk-in patients and scheduled patients. This complex registration system causes a long patient waiting time in outpatient clinics. Different approaches have been proposed to reduce the waiting time. This study uses the integration of discrete event simulation (DES) and agent-based simulation (ABS) to improve patient waiting time and is the first attempt to apply this approach to solve this key problem faced by orthopedic departments. From the data collected, patient behaviors are modeled and incorporated into a massive agent-based simulation. The proposed approach is an aid for analyzing and modifying orthopedic department processes, allows us to consider far more details, and provides more reliable results. After applying the proposed approach, the total waiting time of the orthopedic department fell from 1246.39 minutes to 847.21 minutes. Thus, using the correct simulation model significantly reduces patient waiting time in an orthopedic department. PMID:27195606
Asamoah, Daniel A; Sharda, Ramesh; Rude, Howard N; Doran, Derek
2016-10-12
Long queues and wait times often occur at hospitals and affect smooth delivery of health services. To improve hospital operations, prior studies have developed scheduling techniques to minimize patient wait times. However, these studies lack in demonstrating how such techniques respond to real-time information needs of hospitals and efficiently manage wait times. This article presents a multi-method study on the positive impact of providing real-time scheduling information to patients using the RFID technology. Using a simulation methodology, we present a generic scenario, which can be mapped to real-life situations, where patients can select the order of laboratory services. The study shows that information visibility offered by RFID technology results in decreased wait times and improves resource utilization. We also discuss the applicability of the results based on field interviews granted by hospital clinicians and administrators on the perceived barriers and benefits of an RFID system.
Posted wait times an added advantage to multi-facility systems?
2011-04-01
Methodist Le Bonheur Healthcare in Memphis, TN, is investigating whether posting ED wait times via the internet can positively impact patient flow in the six EDs the health system operates in the Memphis region. The health system began posting wait times in August 2010, resulting in increases in ED volume ranging from 6% to 10%. The health system is monitoring ED arrivals by zip code to assess any impact on load balancing between its busy EDs. One marketing challenge is that a competitor is posting ED wait times as well, but it is posting the time it takes for a patient to be placed in a bed as opposed to the door-to-provider time that Methodist Le Bonheur is posting. The approach has the most impact on lower-acuity patients, but experts worry that in the future, payers may not be reimbursed for ED care for these patients.
... but each organ type has its own individual distribution policy reflects reflect factors that are unique to each organ type: Kidney Waiting time Donor/recipient immune system compatibility Prior living donor ...
Landi, Stefano; Ivaldi, Enrico; Testi, Angela
2018-04-01
In the absence of priority criteria, waiting times are an implicit rationing instrument where the absence or limited use of prices creates an excess of demand. Even in the presence of priority criteria, waiting times may be unfair because they reduce health care demand of patients in lower socio-economic conditions due to high opportunity costs of time or a decay in their health level. Significant evidence has shown a relationship between socioeconomic status and the length of waiting time. The first phase of the study involved an extensive review of the existent literature for the period of 2002-2016 in the main databases (Scopus, PubMed and Science Direct). Twenty-eight met the eligibility criteria. The 27 papers were described and classified. The e mpirical objective of this study was to determine whether socioeconomic characteristics affect waiting time for different health services in the Italian national health system. The services studied were specialist visits, diagnostics tests and elective surgeries. A classification tree and logistic regression models were implemented. Data from the 2013 Italian Health National Survey were used. The analysis found heterogeneous results for different types of service. Individuals with lower education and economic resources have a higher risk of experiencing excessive waiting times for diagnostic and specialist visits. For elective surgery, socioeconomic inequalities are present but appear to be lower. Copyright © 2018 Elsevier B.V. All rights reserved.
Veterans Health Administration
... and Quality in VA Health Care Wait times, satisfaction scores, and quality comparisons for VA health care ... assessment flowchart . ACCESS and QUALITY DATA Wait times, satisfaction scores, and quality comparisons for VA health care ...
Schwierz, Christoph; Wübker, Achim; Wübker, Ansgar; Kuchinke, Björn A
2011-10-01
This paper shows that patients with private health insurance (PHI) are being offered significantly shorter waiting times than patients with statutory health insurance (SHI) in German acute hospital care. This behavior may be driven by the higher expected profitability of PHI relative to SHI holders. Further, we find that hospitals offering private insurees shorter waiting times when compared with SHI holders have a significantly better financial performance than those abstaining from or with less discrimination.
1988-06-01
at Wilford Hall USAF Medical Center significantly reduced the patient wait time at the main outpatient pharmacy. Satellite pharmacies have been ).’l...PRESENTING TO WINDOW 1, 19 MAR 88. 47 C:. A’.’E-:A: -ESCRIRTIONS PER PATIENT ...........48 H. WILFORD HALL MEDICAL CENTER OUTPATIENT QUESTIONNAIRE...that wait times at tne outpatient pharmacy were excessive. It was this concern that motivated the Medical Center Administrator to request that patient
Todokoro, Ayako; Tanaka, Saori C; Kawakubo, Yuki; Yahata, Noriaki; Ishii-Takahashi, Ayaka; Nishimura, Yukika; Kano, Yukiko; Ohtake, Fumio; Kasai, Kiyoto
2018-04-24
Impulsivity, which significantly affects social adaptation, is an important target behavioral characteristic in interventions for attention-deficit hyperactivity disorder (ADHD). Typically, people are willing to wait longer to acquire greater rewards. Impulsivity in ADHD may be associated with brain dysfunction in decision-making involving waiting behavior under such situations. We tested the hypothesis that brain circuitry during a period of waiting (i.e., prior to the acquisition of reward) is altered in adults with ADHD. The participants included 14 medication-free adults with ADHD and 16 healthy controls matched for age, sex, IQ, and handedness. The behavioral task had participants choose between a delayed, larger monetary reward and an immediate, smaller monetary reward, where the reward waiting time actually occurred during functional magnetic resonance imaging measurement. We tested for group differences in the contrast values of blood-oxygen-level dependent signals associated with the length of waiting time, calculated using the parametric modulation method. While the two groups did not differ in the time discounting rate, the delay-sensitive contrast values were significantly lower in the caudate and visual cortex in individuals with ADHD. The higher impulsivity scores were significantly associated with lower delay-sensitive contrast values in the caudate and visual cortex. These results suggest that deficient neural activity affects decision-making involving reward waiting time during intertemporal choice tasks, and provide an explanation for the basis of impulsivity in adult ADHD. © 2018 The Author. Psychiatry and Clinical Neurosciences © 2018 Japanese Society of Psychiatry and Neurology.
The fully actuated traffic control problem solved by global optimization and complementarity
NASA Astrophysics Data System (ADS)
Ribeiro, Isabel M.; de Lurdes de Oliveira Simões, Maria
2016-02-01
Global optimization and complementarity are used to determine the signal timing for fully actuated traffic control, regarding effective green and red times on each cycle. The average values of these parameters can be used to estimate the control delay of vehicles. In this article, a two-phase queuing system for a signalized intersection is outlined, based on the principle of minimization of the total waiting time for the vehicles. The underlying model results in a linear program with linear complementarity constraints, solved by a sequential complementarity algorithm. Departure rates of vehicles during green and yellow periods were treated as deterministic, while arrival rates of vehicles were assumed to follow a Poisson distribution. Several traffic scenarios were created and solved. The numerical results reveal that it is possible to use global optimization and complementarity over a reasonable number of cycles and determine with efficiency effective green and red times for a signalized intersection.
Sobolev, Boris; Levy, Adrian; Hayden, Robert; Kuramoto, Lisa
2006-01-01
Objective To determine whether the probability of undergoing coronary bypass surgery within a certain time was related to the number of patients on the wait list at registration for the operation in a publicly funded health system. Methods A prospective cohort study comparing waiting times among patients registered on wait lists at the hospitals delivering adult cardiac surgery. For each calendar week, the list size, the number of new registrations, and the number of direct admissions immediately after angiography characterized the demand for surgery. Results The length of delay in undergoing treatment was associated with list size at registration, with shorter times for shorter lists (log-rank test 1,198.3, p<.0001). When the list size at registration required clearance time over 1 week patients had 42 percent lower odds of undergoing surgery compared with lists with clearance time less than 1 week (odds ratio [OR] 0.58 percent, 95 percent, confidence interval [CI] 0.53–0.63), after adjustment for age, sex, comorbidity, period, and hospital. The weekly number of new registrations exceeding weekly service capacity had an independent effect toward longer service delays when the list size at registration required clearance time less than 1 week (OR 0.56 percent, 95 percent CI 0.45–0.71), but not for longer lists. Every time the operation was performed for a patient requiring surgery without registration on wait lists, the odds of surgery for listed patients were reduced by 6 percent (OR 0.94, CI 0.93–0.95). Conclusion For wait-listed patients, time to surgery depends on the list size at registration, the number of new registrations, as well as on the weekly number of patients who move immediately from angiography to coronary bypass surgery without being registered on a wait list. Hospital managers may use these findings to improve resource planning and to reduce uncertainty when providing advice on expected treatment delays. PMID:16430599
Interventions to reduce waiting times for elective procedures.
Ballini, Luciana; Negro, Antonella; Maltoni, Susanna; Vignatelli, Luca; Flodgren, Gerd; Simera, Iveta; Holmes, Jane; Grilli, Roberto
2015-02-23
Long waiting times for elective healthcare procedures may cause distress among patients, may have adverse health consequences and may be perceived as inappropriate delivery and planning of health care. To assess the effectiveness of interventions aimed at reducing waiting times for elective care, both diagnostic and therapeutic. We searched the following electronic databases: Cochrane Effective Practice and Organisation of Care (EPOC) Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (1946-), EMBASE (1947-), the Cumulative Index to Nursing and Allied Health Literature (CINAHL), ABI Inform, the Canadian Research Index, the Science, Social Sciences and Humanities Citation Indexes, a series of databases via Proquest: Dissertations & Theses (including UK & Ireland), EconLit, PAIS (Public Affairs International), Political Science Collection, Nursing Collection, Sociological Abstracts, Social Services Abstracts and Worldwide Political Science Abstracts. We sought related reviews by searching the Cochrane Database of Systematic Reviews and the Database of Abstracts of Reviews of Effectiveness (DARE). We searched trial registries, as well as grey literature sites and reference lists of relevant articles. We considered randomised controlled trials (RCTs), controlled before-after studies (CBAs) and interrupted time series (ITS) designs that met EPOC minimum criteria and evaluated the effectiveness of any intervention aimed at reducing waiting times for any type of elective procedure. We considered studies reporting one or more of the following outcomes: number or proportion of participants whose waiting times were above or below a specific time threshold, or participants' mean or median waiting times. Comparators could include any type of active intervention or standard practice. Two review authors independently extracted data from, and assessed risk of bias of, each included study, using a standardised form and the EPOC 'Risk of bias' tool. They classified interventions as follows: interventions aimed at (1) rationing and/or prioritising demand, (2) expanding capacity, or (3) restructuring the intake assessment/referral process.For RCTs when available, we reported preintervention and postintervention values of outcome for intervention and control groups, and we calculated the absolute change from baseline or the effect size with 95% confidence interval (CI). We reanalysed ITS studies that had been inappropriately analysed using segmented time-series regression, and obtained estimates for regression coefficients corresponding to two standardised effect sizes: change in level and change in slope. Eight studies met our inclusion criteria: three RCTs and five ITS studies involving a total of 135 general practices/primary care clinics, seven hospitals and one outpatient clinic. The studies were heterogeneous in terms of types of interventions, elective procedures and clinical conditions; this made meta-analysis unfeasible.One ITS study evaluating prioritisation of demand through a system for streamlining elective surgery services reduced the number of semi-urgent participants waiting longer than the recommended time (< 90 days) by 28 participants/mo, while no effects were found for urgent (< 30 days) versus non-urgent participants (< 365 days).Interventions aimed at restructuring the intake assessment/referral process were evaluated in seven studies. Four studies (two RCTs and two ITSs) evaluated open access, or direct booking/referral: One RCT, which showed that open access to laparoscopic sterilisation reduced waiting times, had very high attrition (87%); the other RCT showed that open access to investigative services reduced waiting times (30%) for participants with lower urinary tract syndrome (LUTS) but had no effect on waiting times for participants with microscopic haematuria. In one ITS study, same-day scheduling for paediatric health clinic appointments reduced waiting times (direct reduction of 25.2 days, and thereafter a decrease of 3.03 days per month), while another ITS study showed no effect of a direct booking system on proportions of participants receiving a colposcopy appointment within the recommended time. One RCT and one ITS showed no effect of distant consultancy (instant photography for dermatological conditions and telemedicine for ear nose throat (ENT) conditions) on waiting times; another ITS study showed no effect of a pooled waiting list on the number of participants waiting for uncomplicated spinal surgery.Overall quality of the evidence for all outcomes, assessed using the GRADE (Grades of Recommendation, Assessment, Development and Evaluation) tool, ranged from low to very low.We found no studies evaluating interventions to increase capacity or to ration demand. As only a handful of low-quality studies are presently available, we cannot draw any firm conclusions about the effectiveness of the evaluated interventions in reducing waiting times. However, interventions involving the provision of more accessible services (open access or direct booking/referral) show some promise.
Electron Waiting Times in Mesoscopic Conductors
NASA Astrophysics Data System (ADS)
Albert, Mathias; Haack, Géraldine; Flindt, Christian; Büttiker, Markus
2012-05-01
Electron transport in mesoscopic conductors has traditionally involved investigations of the mean current and the fluctuations of the current. A complementary view on charge transport is provided by the distribution of waiting times between charge carriers, but a proper theoretical framework for coherent electronic systems has so far been lacking. Here we develop a quantum theory of electron waiting times in mesoscopic conductors expressed by a compact determinant formula. We illustrate our methodology by calculating the waiting time distribution for a quantum point contact and find a crossover from Wigner-Dyson statistics at full transmission to Poisson statistics close to pinch-off. Even when the low-frequency transport is noiseless, the electrons are not equally spaced in time due to their inherent wave nature. We discuss the implications for renewal theory in mesoscopic systems and point out several analogies with level spacing statistics and random matrix theory.
Waiting time distribution in public health care: empirics and theory.
Dimakou, Sofia; Dimakou, Ourania; Basso, Henrique S
2015-12-01
Excessive waiting times for elective surgery have been a long-standing concern in many national healthcare systems in the OECD. How do the hospital admission patterns that generate waiting lists affect different patients? What are the hospitals characteristics that determine waiting times? By developing a model of healthcare provision and analysing empirically the entire waiting time distribution we attempt to shed some light on those issues. We first build a theoretical model that describes the optimal waiting time distribution for capacity constraint hospitals. Secondly, employing duration analysis, we obtain empirical representations of that distribution across hospitals in the UK from 1997-2005. We observe important differences on the 'scale' and on the 'shape' of admission rates. Scale refers to how quickly patients are treated and shape represents trade-offs across duration-treatment profiles. By fitting the theoretical to the empirical distributions we estimate the main structural parameters of the model and are able to closely identify the main drivers of these empirical differences. We find that the level of resources allocated to elective surgery (budget and physical capacity), which determines how constrained the hospital is, explains differences in scale. Changes in benefits and costs structures of healthcare provision, which relate, respectively, to the desire to prioritise patients by duration and the reduction in costs due to delayed treatment, determine the shape, affecting short and long duration patients differently. JEL Classification I11; I18; H51.
Timed Transfer : An Evaluation of Its Structure, Performance and Cost
DOT National Transportation Integrated Search
1983-08-01
Timed transfer is a transit operating strategy in which vehicles from different routes are routed and scheduled to meet simultaneously at common stops to facilitate no-wait or minimum-wait passenger transfers. Timed transfers are being used primarily...
2016-12-01
managed by an RIP. SECREPs are typically critical repair assemblies that require consistently high fill- rates to satisfy maintenance customers ...fill-rate is potentially misreporting performance and areas where short customer wait times could potentially suffice for inventory management . A...supply. Inventory forecasting and management should focus on parts with CWTs that do not satisfy the maintenance customer and 100% fill-rates should
Usefulness of a fast track list for anxious patients in a upper GI endoscopy.
Cardin, Fabrizio; Andreotti, Alessandra; Zorzi, Manuel; Terranova, Claudio; Martella, Bruno; Amato, Bruno; Militello, Carmelo
2012-01-01
To determine whether patients with no alarm signs who ask the endoscopist to shorten their waiting time due to test result anxiety, represent a risk category for a major organic pathology. At our open-access endoscopy service, we set up an expedite list for six months for outpatients who complained that the waiting time for gastroscopy was too long. Over this period we studied 373 gastroscopy patients. In addition to personal details, we collected information on the presence of Hp infection and compliance with dyspepsia guideline indications for gastroscopy. Average waiting time was 38.2 days (SD 12.7). The 66 patients who considered the waiting time too long underwent gastroscopy within 15 days. We made 5 diagnoses of esophageal and gastric tumour and gastric ulcer (7.6%) among the expedite list patients and 14 (4.6%) among those on the normal list (p=0.31). On including duodenal peptic disease in the analysis, the total prevalence rate rose to 19.7% in the short-wait group and to 10.4% (p=0.036) in the longer-wait group. Our data suggests that asking to be fast-tracked does not have prognostic impact on the diagnosis of a major (gastric ulcer and cancer) pathology.
Consumer behaviour in the waiting area.
Mobach, Mark P
2007-02-01
To determine consumer behaviour in the pharmacy waiting area. The applied methods for data-collection were direct observations. Three Dutch community pharmacies were selected for the study. The topics in the observation list were based on available services at each waiting area (brochures, books, illuminated new trailer, children's play area, etc.). Per patient each activity was registered, and at each pharmacy the behaviour was studied for 2 weeks. Most patients only waited during the waiting time at the studied pharmacies. Few consumers obtained written information during their wait. The waiting area may have latent possibilities to expand the information function of the pharmacy and combine this with other activities that distract the consumer from the wait. Transdisciplinary research, combining knowledge from pharmacy practice research with consumer research, has been a useful approach to add information on queueing behaviour of consumers.
Code of Federal Regulations, 2011 CFR
2011-01-01
... required to perform the grading, waiting time, travel time, and any clerical costs involved in issuing a... required to perform the audit, waiting time, travel time, travel expenses and any clerical costs involved... services will be based on the time required to perform the services. The hourly charge shall be $74.08...
Code of Federal Regulations, 2011 CFR
2011-01-01
... required to perform the work, waiting time, travel time, and any clerical costs involved in issuing a... perform the audit, waiting time, travel time, travel expenses and any clerical costs involved in issuing a... specified in this section. (b) Fees for grading services will be based on the time required to perform such...
Code of Federal Regulations, 2013 CFR
2013-01-01
... required to perform the work, waiting time, travel time, and any clerical costs involved in issuing a... perform the audit, waiting time, travel time, travel expenses and any clerical costs involved in issuing a... specified in this section. (b) Fees for grading services will be based on the time required to perform such...
Code of Federal Regulations, 2012 CFR
2012-01-01
... required to perform the work, waiting time, travel time, and any clerical costs involved in issuing a... perform the audit, waiting time, travel time, travel expenses and any clerical costs involved in issuing a... specified in this section. (b) Fees for grading services will be based on the time required to perform such...
Code of Federal Regulations, 2014 CFR
2014-01-01
... required to perform the grading, waiting time, travel time, and any clerical costs involved in issuing a... required to perform the audit, waiting time, travel time, travel expenses and any clerical costs involved... services will be based on the time required to perform the services. The hourly charge shall be $74.08...
Code of Federal Regulations, 2013 CFR
2013-01-01
... required to perform the grading, waiting time, travel time, and any clerical costs involved in issuing a... required to perform the audit, waiting time, travel time, travel expenses and any clerical costs involved... services will be based on the time required to perform the services. The hourly charge shall be $74.08...
Code of Federal Regulations, 2012 CFR
2012-01-01
... required to perform the grading, waiting time, travel time, and any clerical costs involved in issuing a... required to perform the audit, waiting time, travel time, travel expenses and any clerical costs involved... services will be based on the time required to perform the services. The hourly charge shall be $74.08...
Code of Federal Regulations, 2010 CFR
2010-01-01
... required to perform the work, waiting time, travel time, and any clerical costs involved in issuing a... perform the audit, waiting time, travel time, travel expenses and any clerical costs involved in issuing a... specified in this section. (b) Fees for grading services will be based on the time required to perform such...
Code of Federal Regulations, 2014 CFR
2014-01-01
... required to perform the work, waiting time, travel time, and any clerical costs involved in issuing a... perform the audit, waiting time, travel time, travel expenses and any clerical costs involved in issuing a... specified in this section. (b) Fees for grading services will be based on the time required to perform such...
Code of Federal Regulations, 2010 CFR
2010-01-01
... required to perform the grading, waiting time, travel time, and any clerical costs involved in issuing a... required to perform the audit, waiting time, travel time, travel expenses and any clerical costs involved... services will be based on the time required to perform the services. The hourly charge shall be $74.08...
Shortt, Samuel E D; Shaw, Ralph A; Elliott, David; Mackillop, William J
2004-06-01
Provincial governments require timely, economical methods to monitor surgical waiting periods. Although use of prospective procedure-specific registers would be the ideal method, a less elaborate system has been proposed that is based on physician billing data. This study assessed the validity of using the date of the last service billed prior to surgery as a proxy for the beginning of the post-referral, pre-surgical waiting period. We examined charts for 31,824 elective surgical encounters between 1992 and 1996 at an Ontario teaching hospital. The date of the last service before surgery (the last billing date) was compared with the date of the consultant's letter indicating a decision to book surgery (i.e., to begin waiting). Several surgical specialties (but excluding cardiac, orthopedic and gynecologic) had a close correlation between the dates of the last pre-surgery visit and those of the actual decision to place the patient on the waiting list. Similar results were found for 12 of 15 individually studied procedures, including some orthopedic and gynecological procedures. Used judiciously, billing data is a timely, inexpensive and generally accurate method by which provincial governments could monitor trends in waiting times for appropriately selected surgical procedures.
Take, Naoki; Byakika, Sarah; Tasei, Hiroshi; Yoshikawa, Toru
2015-01-01
This study aimed at analyzing the effect of 5S practice on staff motivation, patients’ waiting time and patient satisfaction with health services at hospitals in Uganda. Double-difference estimates were measured for 13 Regional Referral Hospitals and eight General Hospitals implementing 5S practice separately. The study for Regional Referral Hospitals revealed 5S practice had the effect on staff motivation in terms of commitment to work in the current hospital and waiting time in the dispensary in 10 hospitals implementing 5S, but significant difference was not identified on patient satisfaction. The study for General Hospitals indicated the effect of 5S practice on patient satisfaction as well as waiting time, but staff motivation in two hospitals did not improve. 5S practice enables the hospitals to improve the quality of services in terms of staff motivation, waiting time and patient satisfaction and it takes as least four years in Uganda. The fourth year since the commencement of 5S can be a threshold to move forward to the next step, Continuous Quality Improvement. PMID:28299136
NASA Astrophysics Data System (ADS)
Ibrahim, Ireen Munira; Liong, Choong-Yeun; Bakar, Sakhinah Abu; Ahmad, Norazura; Najmuddin, Ahmad Farid
2017-04-01
Emergency department (ED) is the main unit of a hospital that provides emergency treatment. Operating 24 hours a day with limited number of resources invites more problems to the current chaotic situation in some hospitals in Malaysia. Delays in getting treatments that caused patients to wait for a long period of time are among the frequent complaints against government hospitals. Therefore, the ED management needs a model that can be used to examine and understand resource capacity which can assist the hospital managers to reduce patients waiting time. Simulation model was developed based on 24 hours data collection. The model developed using Arena simulation replicates the actual ED's operations of a public hospital in Selangor, Malaysia. The OptQuest optimization in Arena is used to find the possible combinations of a number of resources that can minimize patients waiting time while increasing the number of patients served. The simulation model was modified for improvement based on results from OptQuest. The improvement model significantly improves ED's efficiency with an average of 32% reduction in average patients waiting times and 25% increase in the total number of patients served.
Take, Naoki; Byakika, Sarah; Tasei, Hiroshi; Yoshikawa, Toru
2015-03-31
This study aimed at analyzing the effect of 5S practice on staff motivation, patients' waiting time and patient satisfaction with health services at hospitals in Uganda. Double-difference estimates were measured for 13 Regional Referral Hospitals and eight General Hospitals implementing 5S practice separately. The study for Regional Referral Hospitals revealed 5S practice had the effect on staff motivation in terms of commitment to work in the current hospital and waiting time in the dispensary in 10 hospitals implementing 5S, but significant difference was not identified on patient satisfaction. The study for General Hospitals indicated the effect of 5S practice on patient satisfaction as well as waiting time, but staff motivation in two hospitals did not improve. 5S practice enables the hospitals to improve the quality of services in terms of staff motivation, waiting time and patient satisfaction and it takes as least four years in Uganda. The fourth year since the commencement of 5S can be a threshold to move forward to the next step, Continuous Quality Improvement.
Creation of a diagnostic wait times measurement framework based on evidence and consensus.
Gilbert, Julie E; Dobrow, Mark J; Kaan, Melissa; Dobranowski, Julian; Srigley, John R; Jusko Friedman, Audrey; Irish, Jonathan C
2014-09-01
Public reporting of wait times worldwide has to date focused largely on treatment wait times and is limited in its ability to capture earlier parts of the patient journey. The interval between suspicion and diagnosis or ruling out of cancer is a complex phase of the cancer journey. Diagnostic delays and inefficient use of diagnostic imaging procedures can result in poor patient outcomes, both physical and psychosocial. This study was designed to develop a framework that could be adopted for multiple disease sites across different jurisdictions to enable the measurement of diagnostic wait times and diagnostic delay. Diagnostic benchmarks and targets in cancer systems were explored through a targeted literature review and jurisdictional scan. Cancer system leaders and clinicians were interviewed to validate the information found in the jurisdictional scan. An expert panel was assembled to review and, through a modified Delphi consensus process, provide feedback on a diagnostic wait times framework. The consensus process resulted in agreement on a measurement framework that identified suspicion, referral, diagnosis, and treatment as the main time points for measuring this critical phase of the patient journey. This work will help guide initiatives designed to improve patient access to health services by developing an evidence-based approach to standardization of the various waypoints during the diagnostic pathway. The diagnostic wait times measurement framework provides a yardstick to measure the performance of programs that are designed to manage and expedite care processes between referral and diagnosis or ruling out of cancer. Copyright © 2014 by American Society of Clinical Oncology.
Knudtson, Merril L; Beanlands, Rob; Brophy, James M; Higginson, Lyall; Munt, Brad; Rottger, John
2006-01-01
The Council of the Canadian Cardiovascular Society commissioned working groups to examine issues of access to, and wait times for, various aspects of cardiovascular care. The present article summarizes the deliberations on targets for medically acceptable wait times for access to cardiovascular specialist evaluation and on the performance of non-invasive testing needed to complete this evaluation. Three categories of referral indications were identified: those requiring hospitalization due to substantial ongoing risk of mortality and morbidity; those requiring an expedited early review in an ambulatory setting; and, finally, a larger category in which delays of two to six weeks can be justified. The proposed wait time targets will provide guidance on the timeliness of care to busy clinicians charged with the care of patients with cardiovascular disease, help policy makers appreciate the clinical challenges in providing access to high quality care, and highlight the critical need for a thoughtful review of cardiology human resource requirements. Wait time implementation suggestions are also included, such as the innovative use of disease management and special need clinics. The times proposed assume that available clinical practice guidelines are followed for clinical coronary syndrome management and for treatment of associated conditions such as hypertension, diabetes, renal disease, smoking cessation and lipid disorders. Although media attention tends to focus on wait times for higher profile surgical procedures and high technology imaging, it is likely that patients face the greatest wait-related risk at the earlier phases of care, before the disease has been adequately characterized. PMID:16957798
Geographic determinants of access to pediatric deceased donor kidney transplantation.
Reese, Peter P; Hwang, Hojun; Potluri, Vishnu; Abt, Peter L; Shults, Justine; Amaral, Sandra
2014-04-01
Children receive priority in the allocation of deceased donor kidneys for transplantation in the United States, but because allocation begins locally, geographic differences in population and organ supply may enable variation in pediatric access to transplantation. We assembled a cohort of 3764 individual listings for pediatric kidney transplantation in 2005-2010. For each donor service area, we assigned a category of short (<180 days), medium (181-270 days), or long (>270 days) median waiting time and calculated the ratio of pediatric-quality kidneys to pediatric candidates and the percentage of these kidneys locally diverted to adults. We used multivariable Cox regression analyses to examine the association between donor service area characteristics and time to deceased donor kidney transplantation. The Kaplan-Meier estimate of median waiting time to transplantation was 284 days (95% confidence interval, 263 to 300 days) and varied from 14 to 1313 days across donor service areas. Overall, 29% of pediatric-quality kidneys were locally diverted to adults. Compared with areas with short waiting times, areas with long waiting times had a lower ratio of pediatric-quality kidneys to candidates (3.1 versus 5.9; P<0.001) and more diversions to adults (31% versus 27%; P<0.001). In multivariable regression, a lower kidney to candidate ratio remained associated with longer waiting time (hazard ratio, 0.56 for areas with <2:1 versus reference areas with ≥5:1 kidneys/candidates; P<0.01). Large geographic variation in waiting time for pediatric deceased donor kidney transplantation exists and is highly associated with local supply and demand factors. Future organ allocation policy should address this geographic inequity.
Offline Performance of the Filter Bank EEW Algorithm in the 2014 M6.0 South Napa Earthquake
NASA Astrophysics Data System (ADS)
Meier, M. A.; Heaton, T. H.; Clinton, J. F.
2014-12-01
Medium size events like the M6.0 South Napa earthquake are very challenging for EEW: the damage such events produce can be severe, but it is generally confined to relatively small zones around the epicenter and the shaking duration is short. This leaves a very short window for timely EEW alerts. Algorithms that wait for several stations to trigger before sending out EEW alerts are typically not fast enough for these kind of events because their blind zone (the zone where strong ground motions start before the warnings arrive) typically covers all or most of the area that experiences strong ground motions. At the same time, single station algorithms are often too unreliable to provide useful alerts. The filter bank EEW algorithm is a new algorithm that is designed to provide maximally accurate and precise earthquake parameter estimates with minimum data input, with the goal of producing reliable EEW alerts when only a very small number of stations have been reached by the p-wave. It combines the strengths of single station and network based algorithms in that it starts parameter estimates as soon as 0.5 seconds of data are available from the first station, but then perpetually incorporates additional data from the same or from any number of other stations. The algorithm analyzes the time dependent frequency content of real time waveforms with a filter bank. It then uses an extensive training data set to find earthquake records from the past that have had similar frequency content at a given time since the p-wave onset. The source parameters of the most similar events are used to parameterize a likelihood function for the source parameters of the ongoing event, which can then be maximized to find the most likely parameter estimates. Our preliminary results show that the filter bank EEW algorithm correctly estimated the magnitude of the South Napa earthquake to be ~M6 with only 1 second worth of data at the nearest station to the epicenter. This estimate is then confirmed when updates based on more data from stations at farther distances become available. Because these early estimates saturate at ~M6.5, however, the magnitude estimate might have had to be considered a minimum bound.
Sharma, Anurag; Inder, Brett
2011-08-01
To empirically model the determinants of duration of wait of emergency (triage category 2) patients in an emergency department (ED) focusing on two questions: (i) What is the effect of enhancing the degree of choice for non-urgent (triage category 5) patients on duration of wait for emergency (category 2) patients in EDs; and (ii) What is the effect of co-located GP clinics on duration of wait for emergency patients in EDs? The answers to these questions will help in understanding the effectiveness of demand management strategies, which are identified as one of the solutions to ED crowding. The duration of wait for each patient (difference between arrival time and time first seen by treating doctor) was modelled as a function of input factors (degree of choice, patient characteristics, weekend admission, metro/regional hospital, concentration of emergency (category 2) patients in hospital service area), throughput factors (availability of doctors and nurses) and output factor (hospital bed capacity). The unit of analysis was a patient episode and the model was estimated using a survival regression technique. The degree of choice for non-urgent (category 5) patients has a non-linear effect: more choice for non-urgent patients is associated with longer waits for emergency patients at lower values and shorter waits at higher values of degree of choice. Thus more choice of EDs for non-urgent patients is related to a longer wait for emergency (category 2) patients in EDs. The waiting time for emergency patients in hospital campuses with co-located GP clinics was 19% lower (1.5 min less) on average than for those waiting in campuses without co-located GP clinics. These findings suggest that diverting non-urgent (category 5) patients to an alternative model of care (co-located GP clinics) is a more effective demand management strategy and will reduce ED crowding.
2013-08-01
were treating pre-existing medical conditions using over-the-counter (OTC) medications ( Aspirin ™, Tylenol™, antihistamines, etc.), provided blood...time would decrease to 45 hours for a 150-lb person taking the same dose; a 300 -lb individual taking a 25-mg dose would only need to wait 31 hours...If the 300 -lb person mentioned above had taken a 50- mg dose, the wait time would have been 45 hours, which is approximately the same as the 49
Access to specialist gastroenterology care in Canada: Comparison of wait times and consensus targets
Leddin, Desmond; Armstrong, David; Barkun, Alan NG; Chen, Ying; Daniels, Sandra; Hollingworth, Roger; Hunt, Richard H; Paterson, William G
2008-01-01
BACKGROUND: Monitoring wait times and defining targets for care have been advocated to improve health care delivery related to cancer, heart, diagnostic imaging, joint replacements and sight restoration. There are few data on access to care for digestive diseases, although they pose a greater economic burden than cancer or heart disease in Canada. The present study compared wait times for specialist gastroenterology care with recent, evidence-based, consensus-defined benchmark wait times for a range of digestive diseases. METHODS: Total wait times from primary care referral to investigation were measured for seven digestive disease indications by using the Practice Audit in Gastroenterology program, and were benchmarked against consensus recommendations. RESULTS: Total wait times for 1903 patients who were undergoing investigation exceeded targets for those with probable cancer (median 26 days [25th to 75th percentiles eight to 56 days] versus target of two weeks); probable inflammatory bowel disease (101 days [35 to 209 days] versus two weeks); documented iron deficiency anemia (71 days [19 to 142 days] versus two months); positive fecal occult blood test (73 days [36 to 148 days] versus two months); dyspepsia with alarm symptoms (60 days [23 to 140 days] versus two months); refractory dyspepsia without alarm symptoms (126 days [42 to 225 days] versus two months); and chronic constipation and diarrhea (141 days [68 to 264 days] versus two months). A minority of patients were seen within target times: probable cancer (33% [95% CI 20% to 47%]); probable inflammatory bowel disease (12% [95% CI 1% to 23%]); iron deficiency anemia (46% [95% CI 37% to 55%]); positive occult blood test (41% [95% CI 28% to 54%]); dyspepsia with alarm symptoms (51% [95% CI 41% to 60%]); refractory dyspepsia without alarm symptoms (33% [95% CI 19% to 47%]); and chronic constipation and diarrhea (21% [95% CI 14% to 29%]). DISCUSSION: Total wait times for the seven indications exceeded the consensus targets; 51% to 88% of patients were not seen within the target wait time. Multiple interventions, including adoption of evidence-based management guidelines and provision of economic and human resources, are needed to ensure appropriate access to digestive health care in Canada. Outcomes can be evaluated by the ‘point-of-care’, practice audit methodology used for the present study. PMID:18299735
Valsangkar, Nakul P; Eppstein, Andrew C; Lawson, Rick A; Taylor, Amber N
2017-01-01
There are an increasing number of veterans in the United States, and the current delay and wait times prevent Veterans Affairs institutions from fully meeting the needs of current and former service members. Concrete strategies to improve throughput at these facilities have been sparse. To identify whether lean processes can be used to improve wait times for surgical procedures in Veterans Affairs hospitals. Databases in the Veterans Integrated Service Network 11 Data Warehouse, Veterans Health Administration Support Service Center, and Veterans Information Systems and Technology Architecture/Dynamic Host Configuration Protocol were queried to assess changes in wait times for elective general surgical procedures and clinical volume before, during, and after implementation of lean processes over 3 fiscal years (FYs) at a tertiary care Veterans Affairs medical center. All patients evaluated by the general surgery department through outpatient clinics, clinical video teleconferencing, and e-consultations from October 2011 through September 2014 were included. Patients evaluated through the emergency department or as inpatient consults were excluded. The surgery service and systems redesign service held a value stream analysis in FY 2013, culminating in multiple rapid process improvement workshops. Multidisciplinary teams identified systemic inefficiencies and strategies to improve interdepartmental and patient communication to reduce canceled consultations and cases, diagnostic rework, and no-shows. High-priority triage with enhanced operating room flexibility was instituted to reduce scheduling wait times. General surgery department pilot projects were then implemented mid-FY 2013. Planned outcome measures included wait time, clinic and telehealth volume, number of no-shows, and operative volume. Paired t tests were used to identify differences in outcome measures after the institution of reforms. Following rapid process improvement workshop project rollouts, mean (SD) patient wait times for elective general surgical procedures decreased from 33.4 (8.3) days in FY 2012 to 26.0 (9.5) days in FY 2013 (P = .02). In FY 2014, mean (SD) wait times were half the value of the previous FY at 12.0 (2.1) days (P = .07). This was a 3-fold decrease from wait times in FY 2012 (P = .02). Operative volume increased from 931 patients in FY 2012 to 1090 in FY 2013 and 1072 in FY 2014. Combined clinic, telehealth, and e-consultation encounters increased from 3131 in FY 2012 to 3460 in FY 2013 and 3517 in FY 2014, while the number of no-shows decreased from 366 in FY 2012 to 227 in FY 2014 (P = .02). Improvement in the overall surgical patient experience can stem from multidisciplinary collaboration among systems redesign personnel, clinicians, and surgical staff to reduce systemic inefficiencies. Monitoring and follow-up of system efficiency measures and the employment of lean practices and process improvements can have positive short- and long-term effects on wait times, clinical throughput, and patient care and satisfaction.
Wait times in the emergency department for patients with mental illness
Atzema, Clare L.; Schull, Michael J.; Kurdyak, Paul; Menezes, Natasja M.; Wilton, Andrew S.; Vermuelen, Marian J.; Austin, Peter C.
2012-01-01
Background: It has been suggested that patients with mental illness wait longer for care than other patients in the emergency department. We determined wait times for patients with and without mental health diagnoses during crowded and noncrowded periods in the emergency department. Methods: We conducted a population-based retrospective cohort analysis of adults seen in 155 emergency departments in Ontario between April 2007 and March 2009. We compared wait times and triage scores for patients with mental illness to those for all other patients who presented to the emergency department during the study period. Results: The patients with mental illness (n = 51 381) received higher priority triage scores than other patients, regardless of crowding. The time to assessment by a physician was longer overall for patients with mental illness than for other patients (median 82, interquartile range [IQR] 41–147 min v. median 75 [IQR 36–140] min; p < 0.001). The median time from the decision to admit the patient to hospital to ward transfer was markedly shorter for patients with mental illness than for other patients (median 74 [IQR 15–215] min v. median 152 [IQR 45–605] min; p < 0.001). After adjustment for other variables, patients with mental illness waited 10 minutes longer to see a physician compared with other patients during noncrowded periods (95% confidence interval [CI] 8 to 11), but they waited significantly less time than other patients as crowding increased (mild crowding: −14 [95% CI −12 to −15] min; moderate crowding: −38 [95% CI −35 to −42] min; severe crowding: −48 [95% CI −39 to −56] min; p < 0.001). Interpretation: Patients with mental illness were triaged appropriately in Ontario’s emergency departments. These patients waited less time than other patients to see a physician under crowded conditions and only slightly longer under noncrowded conditions. PMID:23148052
Practical solutions for reducing container ships' waiting times at ports using simulation model
NASA Astrophysics Data System (ADS)
Sheikholeslami, Abdorreza; Ilati, Gholamreza; Yeganeh, Yones Eftekhari
2013-12-01
The main challenge for container ports is the planning required for berthing container ships while docked in port. Growth of containerization is creating problems for ports and container terminals as they reach their capacity limits of various resources which increasingly leads to traffic and port congestion. Good planning and management of container terminal operations reduces waiting time for liner ships. Reducing the waiting time improves the terminal's productivity and decreases the port difficulties. Two important keys to reducing waiting time with berth allocation are determining suitable access channel depths and increasing the number of berths which in this paper are studied and analyzed as practical solutions. Simulation based analysis is the only way to understand how various resources interact with each other and how they are affected in the berthing time of ships. We used the Enterprise Dynamics software to produce simulation models due to the complexity and nature of the problems. We further present case study for berth allocation simulation of the biggest container terminal in Iran and the optimum access channel depth and the number of berths are obtained from simulation results. The results show a significant reduction in the waiting time for container ships and can be useful for major functions in operations and development of container ship terminals.
How Long Are Cancer Patients Waiting for Oncological Therapy in Poland?
Osowiecka, Karolina; Rucinska, Monika; Nowakowski, Jacek J; Nawrocki, Sergiusz
2018-03-23
The five-year relative survival rate in Poland is approximately 10% lower compared with the average for Europe. One of the factors that may contribute to the inferior treatment results in Poland could be the long time between cancer suspicion and the beginning of treatment. The aim of the study was to determine the real waiting time for cancer diagnosis and treatment in Poland. The study was carried out in six cancer centers on a group of 1373 patients, using a questionnaire to interview patients. The median waiting time was estimated as follows: (A) from suspicion (the date of the first visit, with symptoms, to a doctor or a preventive or screening test) until histopathological diagnosis; (B) from suspicion until initial treatment; and (C) from diagnosis until initial treatment. The median times from suspicion to treatment, from suspicion to diagnosis, and from diagnosis to treatment, were 10.6, 5.6, and 5.0 weeks, respectively. Using multivariate analysis, the strongest influence was estimated, in a case of tumor localization, to be the method of initial treatment and facilities. The waiting time for cancer treatment in Poland is too long. The highest influence on waiting time was determined, in the case of tumors, as the type of cancer and factors related to the health care system.
Matsuo, Koji; Opper, Neisha R; Ciccone, Marcia A; Garcia, Jocelyn; Tierney, Katherine E; Baba, Tsukasa; Muderspach, Laila I; Roman, Lynda D
2015-02-01
To examine whether wait time between endometrial biopsy and surgical staging correlates with tumor characteristics and affects survival outcomes in patients with type I endometrial cancer. A retrospective study was conducted to examine patients with grade 1 and 2 endometrioid adenocarcinoma diagnosed by preoperative endometrial biopsy who subsequently underwent hysterectomy-based surgical staging between 2000 and 2013. Patients who received neoadjuvant chemotherapy or hormonal treatment were excluded. Time interval and grade change between endometrial biopsy and hysterectomy were correlated to demographics and survival outcomes. Median wait time was 57 days (range 1-177 days) among 435 patients. Upgrading of the tumor to grade 3 in the hysterectomy specimen was seen in 4.7% of 321 tumors classified as grade 1 and 18.4% of 114 tumors classified as grade 2 on the endometrial biopsy, respectively. Wait time was not associated with grade change (P>.05). Controlling for age, ethnicity, body habitus, medical comorbidities, CA 125 level, and stage, multivariable analysis revealed that wait time was not associated with survival outcomes (5-year overall survival rates, wait time 1-14, 15-42, 43-84, and 85 days or more; 62.5%, 93.6%, 95.2%, and 100%, respectively, P>.05); however, grade 1 to 3 on the hysterectomy specimen remained as an independent prognosticator associated with decreased survival (5-year overall survival rates, grade 1 to 3 compared with grade change 1 to 1, 82.1% compared with 98.5%, P=.01). Among grade 1 preoperative biopsies, grade 1 to 3 was significantly associated with nonobesity (P=.039) and advanced stage (P=.019). Wait time for surgical staging was not associated with decreased survival outcome in patients with type I endometrial cancer.
Estimating the waiting time of multi-priority emergency patients with downstream blocking.
Lin, Di; Patrick, Jonathan; Labeau, Fabrice
2014-03-01
To characterize the coupling effect between patient flow to access the emergency department (ED) and that to access the inpatient unit (IU), we develop a model with two connected queues: one upstream queue for the patient flow to access the ED and one downstream queue for the patient flow to access the IU. Building on this patient flow model, we employ queueing theory to estimate the average waiting time across patients. Using priority specific wait time targets, we further estimate the necessary number of ED and IU resources. Finally, we investigate how an alternative way of accessing ED (Fast Track) impacts the average waiting time of patients as well as the necessary number of ED/IU resources. This model as well as the analysis on patient flow can help the designer or manager of a hospital make decisions on the allocation of ED/IU resources in a hospital.
Stewart, Maureen T.; Horgan, Constance M.; Garnick, Deborah W.; Ritter, Grant; McLellan, A. Thomas
2012-01-01
We evaluate effects of a performance contract (PC) implemented in Delaware in 2001 and participation in quality improvement (QI) programs on waiting time for treatment and length of stay (LOS) using client treatment episode level data from Delaware (n = 12,368) and Maryland (n = 147,151) for 1998 – 2006. Results of difference-in-difference analyses indicate waiting time declined 13 days following the PC, after controlling for client characteristics and historical trends. Participation in the PC and a formal QI program was associated with a decrease of 20 days. LOS increased 22 days under the PC and 24 days under the PC and QI programs, after controlling for client characteristics. The PC and QI program were associated with improvements in LOS and waiting time, although we cannot determine which aspects of the programs (incentives, training, monitoring) resulted in these changes. PMID:22445031
Concordance between partners in desired waiting time to birth for newlyweds in India
Singh, Abhishek; Becker, Stan
2014-01-01
Examining waiting time to birth among newlywed couples is likely to provide insights into the desire for spacing births among newlywed husbands and wives. Data from the Indian National Family Health Survey of 2005-06 is used to examine the desired waiting time (DWT) to birth among newlywed couples. The dependent variable is spousal concordance on desired times. Overall 65 % of couples have concordant DWTs. Among discordant couples, wives were more likely to want to wait longer than their husbands. Couples from richer wealth quintiles were more likely than couples from poorest quintile to have a concordant DWTs. Muslims were less likely than Hindus to have concordant desires. There is a need for spacing methods among newlyweds. This may have implications for the Indian Family Planning Programme which to date has largely focused on sterilization. Programmes need to include newlywed husbands to promote use of spacing methods. PMID:21933466
Public health care and private insurance demand: the waiting time as a link.
Jofre-Bonet, M
2000-01-01
This paper analyzes the effect of waiting times in the Spanish public health system on the demand for private health insurance. Expected utility maximization determines whether or not individuals buy a private health insurance. The decision depends not only on consumer's covariates such as income, socio-demographic characteristics and health status, but also on the quality of the treatment by the public provider. We interpret waiting time as a qualitative attribute of the health care provision. The empirical analysis uses the Spanish Health Survey of 1993. We cope with the absence of income data by using the Spanish Family Budget Survey of 1990-91 as a complementary data set, following the Arellano-Meghir method [4]. Results indicate that a reduction in the waiting time lowers the probability of buying private health insurance. This suggests the existence of a crowd-out in the health care provision market.
Atik, Fernando Antibas; Couto, Carolina Fatima; Tirado, Freddy Ponce; Moraes, Camila Scatolin; Chaves, Renato Bueno; Vieira, Nubia W; Reis, João Gabbardo
2014-01-01
Evaluate the addition of long-distance heart procurement on a heart transplant program and the status of heart transplant recipients waiting list. Between September 2006 and October 2012, 72 patients were listed as heart transplant recipients. Heart transplant was performed in 41 (57%), death on the waiting list occurred in 26 (36%) and heart recovery occurred in 5 (7%). Initially, all transplants were performed with local donors. Long-distance, interstate heart procurement initiated in February 2011. Thirty (73%) transplants were performed with local donors and 11 (27%) with long-distance donors (mean distance=792 km±397). Patients submitted to interstate heart procurement had greater ischemic times (212 min ± 32 versus 90 min±18; P<0.0001). Primary graft dysfunction (distance 9.1% versus local 26.7%; P=0.23) and 1 month and 12 months actuarial survival (distance 90.1% and 90.1% versus local 90% and 86.2%; P=0.65 log rank) were similar among groups. There were marked incremental transplant center volume (64.4% versus 40.7%, P=0.05) with a tendency on less waiting list times (median 1.5 month versus 2.4 months, P=0.18). There was a tendency on reduced waiting list mortality (28.9% versus 48.2%, P=0.09). Incorporation of long-distance heart procurement, despite being associated with longer ischemic times, does not increase morbidity and mortality rates after heart transplant. It enhances viable donor pool, and it may reduce waiting list recipient mortality as well as waiting time.
Non-Poissonian Distribution of Tsunami Waiting Times
NASA Astrophysics Data System (ADS)
Geist, E. L.; Parsons, T.
2007-12-01
Analysis of the global tsunami catalog indicates that tsunami waiting times deviate from an exponential distribution one would expect from a Poisson process. Empirical density distributions of tsunami waiting times were determined using both global tsunami origin times and tsunami arrival times at a particular site with a sufficient catalog: Hilo, Hawai'i. Most sources for the tsunamis in the catalog are earthquakes; other sources include landslides and volcanogenic processes. Both datasets indicate an over-abundance of short waiting times in comparison to an exponential distribution. Two types of probability models are investigated to explain this observation. Model (1) is a universal scaling law that describes long-term clustering of sources with a gamma distribution. The shape parameter (γ) for the global tsunami distribution is similar to that of the global earthquake catalog γ=0.63-0.67 [Corral, 2004]. For the Hilo catalog, γ is slightly greater (0.75-0.82) and closer to an exponential distribution. This is explained by the fact that tsunamis from smaller triggered earthquakes or landslides are less likely to be recorded at a far-field station such as Hilo in comparison to the global catalog, which includes a greater proportion of local tsunamis. Model (2) is based on two distributions derived from Omori's law for the temporal decay of triggered sources (aftershocks). The first is the ETAS distribution derived by Saichev and Sornette [2007], which is shown to fit the distribution of observed tsunami waiting times. The second is a simpler two-parameter distribution that is the exponential distribution augmented by a linear decay in aftershocks multiplied by a time constant Ta. Examination of the sources associated with short tsunami waiting times indicate that triggered events include both earthquake and landslide tsunamis that begin in the vicinity of the primary source. Triggered seismogenic tsunamis do not necessarily originate from the same fault zone, however. For example, subduction-thrust and outer-rise earthquake pairs are evident, such as the November 2006 and January 2007 Kuril Islands tsunamigenic pair. Because of variations in tsunami source parameters, such as water depth above the source, triggered tsunami events with short waiting times are not systematically smaller than the primary tsunami.
Interior effects on comfort in healthcare waiting areas.
Bazley, C; Vink, P; Montgomery, J; Hedge, A
2016-07-21
This study compared the effects of pre-experience and expectations on participant comfort upon waking, arrival to, and after an appointment, as well as the assessment of properly placed Feng Shui elements in three healthcare waiting rooms. Participants assessed comfort levels using self-report surveys. The researcher conducted 'intention interviews' with each doctor to assess the goals of each waiting area design, and conducted a Feng Shui assessment of each waiting area for properly placed Feng Shui elements. The waiting area designed by the Feng Shui expert rated 'most comfortable', followed by the waiting area design by a doctor, and the lowest comfort rating for the conventional waiting room design. Results show a sufficiently strong effect to warrant further research. Awareness of the external environment, paired with pre-experience and expectation, influences comfort for people over time. Fostering and encouraging a holistic approach to comfort utilizing eastern and western concepts and ergonomic principles creates a sense of "placeness" and balance in the design for comfort in built environments. This is new research information on the influences of the comfort experience over time, to include pre-experience, expectations and the placement of elements in the external environment.
Email triage is an effective, efficient and safe way of managing new referrals to a neurologist.
Patterson, Victor; Humphreys, Jenny; Henderson, Mark; Crealey, Grainne
2010-10-01
Patients referred to secondary care in the UK often wait many months to be seen, and the UK government has announced various initiatives to address this issue. Since 2002, we have developed an email referral system which allows some neurological referrals to be managed by advice and investigations rather than by a conventional hospital clinic appointment. This system has previously been shown to reduce clinic attendances and to be acceptable to patients and their general practitioners (GPs). To analyse the effects of an email triage system on waiting times, cost of care and safety over 5 years. Referral numbers and waiting times for clinics using this system were analysed. Cost was determined by comparing detailed costs with those of conventional care. Safety was analysed by examining the GP records of all patients referred from a single practice who had been dealt with by advice or investigation, noting deaths, re-referrals and changes in diagnosis. Waiting times fell from 72 to 4 weeks, despite an increase in referrals. The cost per patient of email referral was about £100, compared with £152 for conventional care, a 35% reduction. Safety data on 120 individuals showed a minor change in diagnosis in three. This system is safe, effective (in reducing waiting times) and efficient. It enables neurologists to focus on patients with significant neurological disease and, if applied more widely, could reduce costs and waiting times for neurology services in the UK.
Waiting Online: A Review and Research Agenda.
ERIC Educational Resources Information Center
Ryan, Gerard; Valverde, Mireia
2003-01-01
Reviews 21 papers based on 13 separate empirical studies on waiting on the Internet, drawn from the areas of marketing, system response time, and quality of service studies. The article proposes an agenda for future research, including extending the range of research methodologies, broadening the definition of waiting on the Internet, and…
An empirical analysis of the impact of choice on waiting times.
Siciliani, Luigi; Martin, Steve
2007-08-01
Policy-makers often claim that enhancing patient choice induces more competition among hospitals and may therefore reduce waiting times. This paper tests this claim using 120 English NHS hospitals over the period 1999-2001. Several proxies for the degree of choice (or competition) are constructed including: (a) the number of hospitals within the catchment area of each hospital; (b) the number of hospitals in the catchment area of each hospital standardised by the population of the catchment area; (c) the inverse of the Herfindahl index (or 'the number of effective competitors'). Several control variables are included: the availability of doctors, junior doctors, nurses, and other personnel; the availability of acute beds; the emergency admission rate; the day-case rate; the average length of inpatient stay; an indicator of case-mix; and mortality and re-admission rates. We find that more choice is significantly associated with lower waiting times at the sample mean (five hospitals) although the quantitative effect is modest: an extra hospital in a catchment area will only reduce waiting by at most a few days (or 1-2% reduction in waiting). There is also some evidence that increases in choice can boost waiting times when the degree of choice is very high (i.e. more than 11 hospitals are included in the catchment area). Copyright 2007 John Wiley & Sons, Ltd.
Soeteman, Marijn; Peters, Vera; Busari, Jamiu O
2015-01-01
In 2013, customer satisfaction surveys showed that patients were unhappy with the services provided at our ambulatory clinic. In response, we performed an appraisal of our services, which resulted in the development of a strategy to reduce waiting time and improve quality of service. Infrastructural changes to our clinic's waiting room, consultation rooms, and back offices were performed, and schedules were redesigned to reduce wait time to 10 minutes and increase consultation time to 20 minutes. Our objective was to identify if this would improve 1) accessibility to caregivers and 2) quality of service and available amenities. We conducted a multi-method survey using 1) a patient flow analysis to analyze the flow of service and understand the impact of our interventions on patient flow and 2) specially designed questionnaires to investigate patients' perceptions of our wait time and how to improve our services. The results showed that 79% of our respondents were called in to see a doctor within 20 minutes upon arrival. More patients (55%) felt that 10-20 minutes was an acceptable wait time. We also observed a perceived increase in satisfaction with wait time (94%). Finally, a large number of patients (97%) were satisfied with the quality of service and with the accessibility to caregivers (94%). The majority of our patients were satisfied with the accessibility to our ambulatory clinics and with the quality of services provided. The appraisal of our operational processes using a patient flow analysis also demonstrated how this strategy could effectively be applied to investigate and improve quality of service in patients.
NASA Astrophysics Data System (ADS)
Palanivel, M.; Priyan, S.; Mala, P.
2017-11-01
In the current global market, organizations use many promotional tools to increase their sales. One such tool is sales teams' initiatives or promotional policies, i.e., free gifts, discounts, packaging, etc. This phenomenon motivates the retailer/or buyer to order a large inventory lot so as to take full benefit of promotional policies. In view of this the present paper considers a two-warehouse (owned and rented) inventory problem for a non-instantaneous deteriorating item with inflation and time value of money over a finite planning horizon. Here, demand depends on the sales team's initiatives and shortages are partially backlogged at a rate dependent on the duration of waiting time up to the arrival of next lot. We design an algorithm to obtain the optimal replenishment strategies. Numerical analysis is also given to show the applicability of the proposed model in real-world two-warehouse inventory problems.
Wait Time for Treatment in Hospital Emergency Departments: 2009
... on Vital and Health Statistics Annual Reports Health Survey Research Methods Conference Reports from the National Medical Care ... SOURCE: CDC/NCHS, National Hospital Ambulatory Medical Care ... with previous research, longer wait time for treatment was associated with ...
ERIC Educational Resources Information Center
Hunter, Madeline
1973-01-01
Every day contains those unavoidable waiting periods, but they need not be unproductive. You can convert waiting time to learning with the help of sponge activities---learning activities which "sop up" those precious droplets of time that would otherwise be lost. (Author)
The Influence of Prior Choices on Current Choice
de la Piedad, Xochitl; Field, Douglas; Rachlin, Howard
2006-01-01
Three pigeons chose between random-interval (RI) and tandem, continuous-reinforcement, fixed-interval (crf-FI) reinforcement schedules by pecking either of two keys. As long as a pigeon pecked on the RI key, both keys remained available. If a pigeon pecked on the crf-FI key, then the RI key became unavailable and the crf-FI timer began to time out. With this procedure, once the RI key was initially pecked, the prospective value of both alternatives remained constant regardless of time spent pecking on the RI key without reinforcement (RI waiting time). Despite this constancy, the rate at which pigeons switched from the RI to the crf-FI decreased sharply as RI waiting time increased. That is, prior choices influenced current choice—an exercise effect. It is argued that such influence (independent of reinforcement contingencies) may serve as a sunk-cost commitment device in self-control situations. In a second experiment, extinction was programmed if RI waiting time exceeded a certain value. Rate of switching to the crf-FI first decreased and then increased as the extinction point approached, showing sensitivity to both prior choices and reinforcement contingencies. In a third experiment, crf-FI availability was limited to a brief window during the RI waiting time. When constrained in this way, switching occurred at a high rate regardless of when, during the RI waiting time, the crf-FI became available. PMID:16602373
A model of return intervals between earthquake events
NASA Astrophysics Data System (ADS)
Zhou, Yu; Chechkin, Aleksei; Sokolov, Igor M.; Kantz, Holger
2016-06-01
Application of the diffusion entropy analysis and the standard deviation analysis to the time sequence of the southern California earthquake events from 1976 to 2002 uncovered scaling behavior typical for anomalous diffusion. However, the origin of such behavior is still under debate. Some studies attribute the scaling behavior to the correlations in the return intervals, or waiting times, between aftershocks or mainshocks. To elucidate a nature of the scaling, we applied specific reshulffling techniques to eliminate correlations between different types of events and then examined how it affects the scaling behavior. We demonstrate that the origin of the scaling behavior observed is the interplay between mainshock waiting time distribution and the structure of clusters of aftershocks, but not correlations in waiting times between the mainshocks and aftershocks themselves. Our findings are corroborated by numerical simulations of a simple model showing a very similar behavior. The mainshocks are modeled by a renewal process with a power-law waiting time distribution between events, and aftershocks follow a nonhomogeneous Poisson process with the rate governed by Omori's law.
Hosking, Jonathan; Gibson, Colin
2016-07-01
The introduction of a single point referral system that prioritises clients depending on case complexity and overcomes the need for re-admittance to a waiting list via a review system has been shown to significantly reduce maximum waiting times for a Posture and Mobility (Special Seating) Service from 102.0 ± 24.33 weeks to 19.2 ± 8.57 weeks (p = 0.015). Using this service model linear regression revealed a statistically significant improvement in the performance outcome of prescribed seating solutions with shorter Episode of Care completion times (p = 0.023). In addition, the number of Episodes of Care completed per annum was significantly related to the Episode of Care completion time (p = 0.019). In conclusion, it is recommended that it may be advantageous to apply this service model to other assistive technology services in order to reduce waiting times and to improve clinical outcomes.
Hung, Shih-Chiang; Kung, Chia-Te; Hung, Chih-Wei; Liu, Ber-Ming; Liu, Jien-Wei; Chew, Ghee; Chuang, Hung-Yi; Lee, Wen-Huei; Lee, Tzu-Chi
2014-08-23
The adverse effects of delayed admission to the intensive care unit (ICU) have been recognized in previous studies. However, the definitions of delayed admission varies across studies. This study proposed a model to define "delayed admission", and explored the effect of ICU-waiting time on patients' outcome. This retrospective cohort study included non-traumatic adult patients on mechanical ventilation in the emergency department (ED), from July 2009 to June 2010. The primary outcomes measures were 21-ventilator-day mortality and prolonged hospital stays (over 30 days). Models of Cox regression and logistic regression were used for multivariate analysis. The non-delayed ICU-waiting was defined as a period in which the time effect on mortality was not statistically significant in a Cox regression model. To identify a suitable cut-off point between "delayed" and "non-delayed", subsets from the overall data were made based on ICU-waiting time and the hazard ratio of ICU-waiting hour in each subset was iteratively calculated. The cut-off time was then used to evaluate the impact of delayed ICU admission on mortality and prolonged length of hospital stay. The final analysis included 1,242 patients. The time effect on mortality emerged after 4 hours, thus we deduced ICU-waiting time in ED > 4 hours as delayed. By logistic regression analysis, delayed ICU admission affected the outcomes of 21 ventilator-days mortality and prolonged hospital stay, with odds ratio of 1.41 (95% confidence interval, 1.05 to 1.89) and 1.56 (95% confidence interval, 1.07 to 2.27) respectively. For patients on mechanical ventilation at the ED, delayed ICU admission is associated with higher probability of mortality and additional resource expenditure. A benchmark waiting time of no more than 4 hours for ICU admission is recommended.
Access to Care for Youth in a State Mental Health System: A Simulated Patient Approach.
Olin, Su-Chin Serene; O'Connor, Briannon C; Storfer-Isser, Amy; Clark, Lisa J; Perkins, Matthew; Hudson Scholle, Sarah; Whitmyre, Emma D; Hoagwood, Kimberly; Horwitz, Sarah McCue
2016-05-01
To examine access to psychiatric care for adolescents with depression in outpatient specialty clinics within a state mental health system, using a simulated patient approach. Trained callers posed as the mother of a 14-year-old girl with depression, following a script. A stratified random sample (n = 264) of 340 state-licensed outpatient mental health clinics that serve youth was selected. Clinics were randomly assigned to season and insurance condition. We examined whether access varied by season, clinic characteristics, and caller insurance type. Weighted logistic and linear mixed effects regression models were fitted to examine associations with appointment availability and wait times. Among clinics at which a treatment appointment could be scheduled, appointment availability differed by season. Clinics that had participated in state-sponsored trainings targeting access were more available. Wait times for treatment appointments varied by season and region. Wait times in New York City were shorter than in some other regions. Although callers were 4.1 times more likely to be able to schedule a psychiatry appointment in the spring, wait times for psychiatry appointments were significantly longer in the spring than in the summer (49.9 vs. 36.7 days). Wait times for therapy appointments were significantly shorter in community than in hospital clinics (19.1 days vs. 35.3 days). Access to psychiatric care for youth with depression was found to be variable in a state system. State-sponsored trainings on strategies to reduce wait times appear to improve care access. The simulated patient approach has promise for monitoring the impact of health care policy reforms on care quality measures. Published by Elsevier Inc.
Access to Care for Youth in a State Mental Health System: A Simulated Patient Approach
Olin, Su-chin Serene; O'Connor, Briannon C.; Storfer-Isser, Amy; Clark, Lisa J.; Perkins, Matthew; Scholle, Sarah Hudson; Whitmyre, Emma D.; Hoagwood, Kimberly; Horwitz, Sarah McCue
2016-01-01
Objective To examine access to psychiatric care for adolescents with depression in outpatient specialty clinics within a state mental health system, using a simulated patient approach. Method Trained callers posed as the mother of a 14-year-old female with depression, following a script. A stratified random sample (n = 264) of 340 state-licensed outpatient mental health clinics that serve youth was selected. Clinics were randomly assigned to season and insurance condition. We examined if access varied by season, clinic characteristics, and caller insurance type. Weighted logistic and linear mixed effects regression models were fitted to examine associations with appointment availability and wait times. Results Among clinics where a treatment appointment could be scheduled, appointment availability differed by season. Clinics who had participated in state-sponsored trainings targeting access were more available. Wait times for treatment appointments varied by season and region. Wait times in New York City were shorter than in some other regions. Although callers were 4.1 times more likely to be able to schedule a psychiatry appointment in the spring, wait times for psychiatry appointments were significantly longer in the spring than in the summer (49.9 vs. 36.7 days). Wait times for therapy appointments were significantly shorter in community than hospital clinics (19.1 days vs. 35.3 days). Conclusion Access to psychiatric care for youth with depression was found to be variable in a state system. State-sponsored trainings on strategies to reduce wait times appear to improve care access. The simulated patient approach has promise for monitoring the impact of healthcare policy reforms on care quality measures. PMID:27126853
Examining Passenger Flow Choke Points at Airports Using Discrete Event Simulation
NASA Technical Reports Server (NTRS)
Brown, Jeremy R.; Madhavan, Poomima
2011-01-01
The movement of passengers through an airport quickly, safely, and efficiently is the main function of the various checkpoints (check-in, security. etc) found in airports. Human error combined with other breakdowns in the complex system of the airport can disrupt passenger flow through the airport leading to lengthy waiting times, missing luggage and missed flights. In this paper we present a model of passenger flow through an airport using discrete event simulation that will provide a closer look into the possible reasons for breakdowns and their implications for passenger flow. The simulation is based on data collected at Norfolk International Airport (ORF). The primary goal of this simulation is to present ways to optimize the work force to keep passenger flow smooth even during peak travel times and for emergency preparedness at ORF in case of adverse events. In this simulation we ran three different scenarios: real world, increased check-in stations, and multiple waiting lines. Increased check-in stations increased waiting time and instantaneous utilization. while the multiple waiting lines decreased both the waiting time and instantaneous utilization. This simulation was able to show how different changes affected the passenger flow through the airport.
Anomalous diffusion for bed load transport with a physically-based model
NASA Astrophysics Data System (ADS)
Fan, N.; Singh, A.; Foufoula-Georgiou, E.; Wu, B.
2013-12-01
Diffusion of bed load particles shows both normal and anomalous behavior for different spatial-temporal scales. Understanding and quantifying these different types of diffusion is important not only for the development of theoretical models of particle transport but also for practical purposes, e.g., river management. Here we extend a recently proposed physically-based model of particle transport by Fan et al. [2013] to further develop an Episodic Langevin equation (ELE) for individual particle motion which reproduces the episodic movement (start and stop) of sediment particles. Using the proposed ELE we simulate particle movements for a large number of uniform size particles, incorporating different probability distribution functions (PDFs) of particle waiting time. For exponential PDFs of waiting times, particles reveal ballistic motion in short time scales and turn to normal diffusion at long time scales. The PDF of simulated particle travel distances also shows a change in its shape from exponential to Gamma to Gaussian with a change in timescale implying different diffusion scaling regimes. For power-law PDF (with power - μ) of waiting times, the asymptotic behavior of particles at long time scales reveals both super-diffusion and sub-diffusion, however, only very heavy tailed waiting times (i.e. 1.0 < μ < 1.5) could result in sub-diffusion. We suggest that the contrast between our results and previous studies (for e.g., studies based on fractional advection-diffusion models of thin/heavy tailed particle hops and waiting times) results could be due the assumption in those studies that the hops are achieved instantaneously, but in reality, particles achieve their hops within finite times (as we simulate here) instead of instantaneously, even if the hop times are much shorter than waiting times. In summary, this study stresses on the need to rethink the alternative models to the previous models, such as, fractional advection-diffusion equations, for studying the anomalous diffusion of bed load particles. The implications of these results for modeling sediment transport are discussed.
Shortt, Samuel E.D.; Shaw, Ralph A.; Elliott, David; Mackillop, William J.
2004-01-01
Background Provincial governments require timely, economical methods to monitor surgical waiting periods. Although use of prospective procedure-specific registers would be the ideal method, a less elaborate system has been proposed that is based on physician billing data. This study assessed the validity of using the date of the last service billed prior to surgery as a proxy for the beginning of the post-referral, pre-surgical waiting period. Method We examined charts for 31 824 elective surgical encounters between 1992 and 1996 at an Ontario teaching hospital. The date of the last service before surgery (the last billing date) was compared with the date of the consultant's letter indicating a decision to book surgery (i.e., to begin waiting). Results Several surgical specialties (but excluding cardiac, orthopedic and gynecologic) had a close correlation between the dates of the last pre-surgery visit and those of the actual decision to place the patient on the waiting list. Similar results were found for 12 of 15 individually studied procedures, including some orthopedic and gynecological procedures. Conclusion Used judiciously, billing data is a timely, inexpensive and generally accurate method by which provincial governments could monitor trends in waiting times for appropriately selected surgical procedures. PMID:15264378
The unethical focus on access: a study of medical ethics and the waiting-time guarantee.
Karlberg, H I; Brinkmo, B-M
2009-03-01
All civilized societies favour ethical principles of equity. In healthcare, these principles generally focus on needs for medical care. Methods for establishing priorities among such needs are instrumental in this process. In this study, we analysed whether rules on access to healthcare, waiting-time guarantees, conflict with ethical principles of distributive justice. We interviewed directors, managers and other decision-makers of various healthcare providers of hospitals, primary care organizations and purchasing offices. We also conducted focus group interviews with professionals from a number of distinct medical areas. Our informants and their co-workers were reasonably familiar with the ethical platforms for priority-setting established by the Swedish parliament, giving the sickest patients complete priority. However, to satisfy the waiting-time guarantees, the informants often had to make priority decisions contrary to the ethical principles by favouring access before needs to keep waiting times within certain limits. The common opinion was that the waiting-time guarantee leads to crowding-out effects, overruling the ethical principles based on needs. For more than a decade, the interpretation in Sweden of the equitable principle based on medical needs has been distorted through political decisions, leading to healthcare providers giving priority to access rather than needs for care.
Availability of Maintained Systems
1983-03-01
o -4 >1 w Administrative0 and Logistic Time 0 -4W 0 E-44 4q Operating Time ( > .1 Preventive Maintenance | 04 SOperating Time t Ready Time Operatinf...point in time. It excludes ready time, preventive-maintenance downtime, logistic time, and waiting or administrative downtime. It may be expressed as: A...satisfactorily at a given point in time. It excludes logistic tim-3 and waiting or administrative downtime. It includes active preventive and
Appointment at Palmer Appointment at Fairbanks Schedule My Road Test Road Test Wait List DRIVERS Get My Card Track My ID or License Practice Knowledge Test Register to Vote VEHICLES Renew My Registration Road Test Road Test Wait List Locations & Hours Office Hours Check Wait Times Dealer and Fleet
Strategic Attention Deployment for Delay of Gratification in Working and Waiting Situations.
ERIC Educational Resources Information Center
Peake, Philip K.; Hebl, Michelle; Mischel, Walter
2002-01-01
Two studies examined whether effects of attention to rewards during a delay of gratification task in waiting situations affects preschoolers' ability to delay gratification in working situations. Findings show that when work provides distraction, attention on rewards reduces delay time whether working or waiting; when work is not engaging,…
Impact of visual art on patient behavior in the emergency department waiting room.
Nanda, Upali; Chanaud, Cheryl; Nelson, Michael; Zhu, Xi; Bajema, Robyn; Jansen, Ben H
2012-07-01
Wait times have been reported to be one of the most important concerns for people visiting emergency departments (EDs). Affective states significantly impact perception of wait time. There is substantial evidence that art depicting nature reduces stress levels and anxiety, thus potentially impacting the waiting experience. To analyze the effect of visual art depicting nature (still and video) on patients' and visitors' behavior in the ED. A pre-post research design was implemented using systematic behavioral observation of patients and visitors in the ED waiting rooms of two hospitals over a period of 4 months. Thirty hours of data were collected before and after new still and video art was installed at each site. Significant reduction in restlessness, noise level, and people staring at other people in the room was found at both sites. A significant decrease in the number of queries made at the front desk and a significant increase in social interaction were found at one of the sites. Visual art has positive effects on the ED waiting experience. Copyright © 2012 Elsevier Inc. All rights reserved.
Hybrid stochastic simplifications for multiscale gene networks.
Crudu, Alina; Debussche, Arnaud; Radulescu, Ovidiu
2009-09-07
Stochastic simulation of gene networks by Markov processes has important applications in molecular biology. The complexity of exact simulation algorithms scales with the number of discrete jumps to be performed. Approximate schemes reduce the computational time by reducing the number of simulated discrete events. Also, answering important questions about the relation between network topology and intrinsic noise generation and propagation should be based on general mathematical results. These general results are difficult to obtain for exact models. We propose a unified framework for hybrid simplifications of Markov models of multiscale stochastic gene networks dynamics. We discuss several possible hybrid simplifications, and provide algorithms to obtain them from pure jump processes. In hybrid simplifications, some components are discrete and evolve by jumps, while other components are continuous. Hybrid simplifications are obtained by partial Kramers-Moyal expansion [1-3] which is equivalent to the application of the central limit theorem to a sub-model. By averaging and variable aggregation we drastically reduce simulation time and eliminate non-critical reactions. Hybrid and averaged simplifications can be used for more effective simulation algorithms and for obtaining general design principles relating noise to topology and time scales. The simplified models reproduce with good accuracy the stochastic properties of the gene networks, including waiting times in intermittence phenomena, fluctuation amplitudes and stationary distributions. The methods are illustrated on several gene network examples. Hybrid simplifications can be used for onion-like (multi-layered) approaches to multi-scale biochemical systems, in which various descriptions are used at various scales. Sets of discrete and continuous variables are treated with different methods and are coupled together in a physically justified approach.
NASA Astrophysics Data System (ADS)
Palanivel, M.; Uthayakumar, R.
2015-07-01
This paper deals with an economic order quantity (EOQ) model for non-instantaneous deteriorating items with price and advertisement dependent demand pattern under the effect of inflation and time value of money over a finite planning horizon. In this model, shortages are allowed and partially backlogged. The backlogging rate is dependent on the waiting time for the next replenishment. This paper aids the retailer in minimising the total inventory cost by finding the optimal interval and the optimal order quantity. An algorithm is designed to find the optimum solution of the proposed model. Numerical examples are given to demonstrate the results. Also, the effect of changes in the different parameters on the optimal total cost is graphically presented and the implications are discussed in detail.
The waiting time problem in a model hominin population.
Sanford, John; Brewer, Wesley; Smith, Franzine; Baumgardner, John
2015-09-17
Functional information is normally communicated using specific, context-dependent strings of symbolic characters. This is true within the human realm (texts and computer programs), and also within the biological realm (nucleic acids and proteins). In biology, strings of nucleotides encode much of the information within living cells. How do such information-bearing nucleotide strings arise and become established? This paper uses comprehensive numerical simulation to understand what types of nucleotide strings can realistically be established via the mutation/selection process, given a reasonable timeframe. The program Mendel's Accountant realistically simulates the mutation/selection process, and was modified so that a starting string of nucleotides could be specified, and a corresponding target string of nucleotides could be specified. We simulated a classic pre-human hominin population of at least 10,000 individuals, with a generation time of 20 years, and with very strong selection (50% selective elimination). Random point mutations were generated within the starting string. Whenever an instance of the target string arose, all individuals carrying the target string were assigned a specified reproductive advantage. When natural selection had successfully amplified an instance of the target string to the point of fixation, the experiment was halted, and the waiting time statistics were tabulated. Using this methodology we tested the effect of mutation rate, string length, fitness benefit, and population size on waiting time to fixation. Biologically realistic numerical simulations revealed that a population of this type required inordinately long waiting times to establish even the shortest nucleotide strings. To establish a string of two nucleotides required on average 84 million years. To establish a string of five nucleotides required on average 2 billion years. We found that waiting times were reduced by higher mutation rates, stronger fitness benefits, and larger population sizes. However, even using the most generous feasible parameters settings, the waiting time required to establish any specific nucleotide string within this type of population was consistently prohibitive. We show that the waiting time problem is a significant constraint on the macroevolution of the classic hominin population. Routine establishment of specific beneficial strings of two or more nucleotides becomes very problematic.
[Do physicians' gender and workload affect patients?].
Finnvold, Jon Erik
2008-10-23
The article discusses the effect of general practitioners' gender and workload on patients' experience with consultation time, waiting hours, use of out-of-hours services and planned health visits. Data were retrieved from the 2003 version of Statistics Norway's household panel study (5000 persons) and the National Insurance administration's register of regular general practitioners. Health condition was the most important factor related to patient experiences. A high workload was neither associated with more frequent use of out-of-hours services nor satisfaction with time spent in consultation. These results apply to physicians of both genders. Patients who used a female physician with a large workload had to wait longer for an appointment and more often reported dissatisfaction with the waiting time; this was not the case for male physicians. However, male physicians with a low workload had shorter waiting times. Patients who use practitioners with a high workload may have chosen their doctor more deliberately than others, which may be an explanation for few negative outcomes for physicians with a high workload. It is unlikely that these physicians would be as popular if the patients had fewer appointments, shorter consultations or more often had to use the out-of-hours services. Longer waiting time for appointments with female doctors may be related to more part time work, and the fact that female physicians more often are engaged in group practices.
Impact of pharmacy automation on patient waiting time: an application of computer simulation.
Tan, Woan Shin; Chua, Siang Li; Yong, Keng Woh; Wu, Tuck Seng
2009-06-01
This paper aims to illustrate the use of computer simulation in evaluating the impact of a prototype automated dispensing system on waiting time in an outpatient pharmacy and its potential as a routine tool in pharmacy management. A discrete event simulation model was developed to investigate the impact of a prototype automated dispensing system on operational efficiency and service standards in an outpatient pharmacy. The simulation results suggest that automating the prescription-filing function using a prototype that picks and packs at 20 seconds per item will not assist the pharmacy in achieving the waiting time target of 30 minutes for all patients. Regardless of the state of automation, to meet the waiting time target, 2 additional pharmacists are needed to overcome the process bottleneck at the point of medication dispense. However, if the automated dispensing is the preferred option, the speed of the system needs to be twice as fast as the current configuration to facilitate the reduction of the 95th percentile patient waiting time to below 30 minutes. The faster processing speed will concomitantly allow the pharmacy to reduce the number of pharmacy technicians from 11 to 8. Simulation was found to be a useful and low cost method that allows an otherwise expensive and resource intensive evaluation of new work processes and technology to be completed within a short time.
Delaurier, Ashley; Bernatsky, Sasha; Raymond, Marie-Hélène; Feldman, Debbie Ehrmann
2013-01-01
Although arthritis is the leading cause of pain and disability in Canada, and physical therapy (PT) and occupational therapy (OT) are beneficial both for chronic osteoarthritis (OA) and for inflammatory arthritis such as rheumatoid arthritis (RA), there appear to be problems with access to such services. The aim of this study was to document wait times from referral by physician to consultation with PT or OT in the public health care system for people with arthritis in Quebec, Canada. Appointments were requested by telephone, using hypothetical case scenarios; wait times were defined as the time between initial request and appointment date. Descriptive statistics were used to examine the wait times in relation to diagnosis, service provider and geographic area. For both scenarios (OA and RA) combined, 13% were offered an appointment within 6 months, 13% offered given an appointment within 6-12 months, 24% were told they would need to wait longer than 12 months, and 22% were refused services. The remaining 28% were told they would require an evaluation appointment for functional assessment before being given an appointment for therapy. No difference was found between RA and OA diagnoses. Our study suggests that most people with arthritis living in the province of Quebec are not receiving publicly accessible PT or OT intervention in a timely manner.
Merkow, Ryan P; Bilimoria, Karl Y; Sherman, Karen L; McCarter, Martin D; Gordon, Howard S; Bentrem, David J
2013-07-01
Timeliness of cancer treatment is an important aspect of health care quality. Veterans Affairs Medical Centers (VAMCs) are expected to treat a growing number of patients with cancer. Our objectives were to examine treatment times from diagnosis to first-course therapy for patients with colon and rectal cancers and assess factors associated with prolonged wait times. From the VA Central Cancer Registry, patients who underwent colon or rectal resection for cancer from 1998 to 2008 were identified. Time from diagnosis to definitive cancer-directed therapy was measured, and multivariable regression methods were used to determine predictors of prolonged wait times for colon (≥ 45 days) and rectal (≥ 60 days) cancers. From 124 VAMCs, 14,097 patients underwent colectomy, and 3,390 underwent rectal resection for cancer. For colon cancer, the median time to treatment increased by 68% over time (P < .001). From 2007 to 2008, the median time to colectomy was 32 days. Predictors of prolonged wait times included age ≥ 55 years (v < 55 years), time period (2007 to 2008 v 1998 to 2000), black race (v white), marriage status (married v unmarried), high-volume center status (v low volume), and treatment at a different hospital (v same hospital as initial diagnosis; all P < .05). For rectal cancer, the overall median time to first-course treatment increased by 74% (P < .001). From 2007 to 2008, the median time to proctectomy was 47 days. Similar predictors of prolonged wait times were identified for rectal cancer. Time to first treatment has increased for patients with colon and rectal cancers at VAMCs. Patient, tumor, and hospital factors are associated with prolonged time to treatment.
Hsu, Chia-Fen; Benikos, Nicholas; Sonuga-Barke, Edmund J S
2015-04-01
Spontaneous very low frequency oscillations (VLFO), seen in the resting brain, are attenuated when individuals are working on attention demanding tasks or waiting for rewards (Hsu et al., 2013). Individuals with attention-deficit/hyperactivity disorder (ADHD) display excess VLFO when working on attention tasks. They also have difficulty waiting for rewards. Here we examined the waiting brain signature in ADHD and its association with impulsive choice. DC-EEG from 21 children with ADHD and 21 controls (9-15 years) were collected under four conditions: (i) resting; (ii) choosing to wait; (iii) being "forced" to wait; and (iv) working on a reaction time task. A questionnaire measured two components of impulsive choice. Significant VLFO reductions were observed in controls within anterior brain regions in both working and waiting conditions. Individuals with ADHD showed VLFO attenuation while working but to a reduced level and none at all when waiting. A closer inspection revealed an increase of VLFO activity in temporal regions during waiting. Excess VLFO activity during waiting was associated with parents' ratings of temporal discounting and delay aversion. The results highlight the potential role for waiting-related spontaneous neural activity in the pathophysiology of impulsive decision-making of ADHD. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Oliveira, Ilione Kruschewsky Costa Sousa; Arsati, Ynara Bosco de Oliveira Lima; Basting, Roberta Tarkany; França, Fabiana Mantovani Gomes
2012-01-01
This study aimed to assess the effect of post-cementation waiting time for core preparation of cemented cast posts and cores had on retention in the root canal, using two different luting materials. Sixty extracted human canines were sectioned 16 mm from the root apex. After cast nickel-chromium metal posts and cores were fabricated and luted with zinc phosphate (ZP) cement or resin cement (RC), the specimens were divided into 3 groups (n = 10) according to the waiting time for core preparation: no preparation (control), 15 minutes, or 1 week after the core cementation. At the appropriate time, the specimens were subjected to a tensile load test (0.5 mm/min) until failure. Two-way ANOVA (time versus cement) and the Tukey tests (P < 0.05) showed significantly higher (P < 0.05) tensile strength values for the ZP cement groups than for the RC groups. Core preparation and post-cementation waiting time for core recontouring did not influence the retention strength. ZP was the best material for intraradicular metal post cementation.
Contributions to Engineering Models of Human-Computer Interaction. Volume 1.
1988-05-06
for those readers wishing to replicate my results. Volume II is on file in the Carnegie-Mellon library and is available upon request from the author...a 50 mieec 10 10 10 10 170 170 170 Moo, sf 4 170 Mooc Figure 4-20: Schedule chart of the perception-wait algorithm for the detection span task
Soeteman, Marijn; Peters, Vera; Busari, Jamiu O
2015-01-01
Objective In 2013, customer satisfaction surveys showed that patients were unhappy with the services provided at our ambulatory clinic. In response, we performed an appraisal of our services, which resulted in the development of a strategy to reduce waiting time and improve quality of service. Infrastructural changes to our clinic’s waiting room, consultation rooms, and back offices were performed, and schedules were redesigned to reduce wait time to 10 minutes and increase consultation time to 20 minutes. Our objective was to identify if this would improve 1) accessibility to caregivers and 2) quality of service and available amenities. Design We conducted a multi-method survey using 1) a patient flow analysis to analyze the flow of service and understand the impact of our interventions on patient flow and 2) specially designed questionnaires to investigate patients’ perceptions of our wait time and how to improve our services. Results The results showed that 79% of our respondents were called in to see a doctor within 20 minutes upon arrival. More patients (55%) felt that 10–20 minutes was an acceptable wait time. We also observed a perceived increase in satisfaction with wait time (94%). Finally, a large number of patients (97%) were satisfied with the quality of service and with the accessibility to caregivers (94%). Conclusion The majority of our patients were satisfied with the accessibility to our ambulatory clinics and with the quality of services provided. The appraisal of our operational processes using a patient flow analysis also demonstrated how this strategy could effectively be applied to investigate and improve quality of service in patients. PMID:25848303
Common, Jessica L; Mariathas, Hensley H; Parsons, Kaylah; Greenland, Jonathan D; Harris, Scott; Bhatia, Rick; Byrne, SuzanneC
2018-06-04
A multidisciplinary, centralized referral program was established at our institution in 2014 to reduce delays in lung cancer diagnosis and treatment following diagnostic imaging observed with the traditional, primary care provider-led referral process. The main objectives of this retrospective cohort study were to determine if referral to a Thoracic Triage Panel (TTP): 1) expedites lung cancer diagnosis and treatment initiation; and 2) leads to more appropriate specialist consultation. Patients with a diagnosis of lung cancer and initial diagnostic imaging between March 1, 2015, and February 29, 2016, at a Memorial University-affiliated tertiary care centre in St John's, Newfoundland, were identified and grouped according to whether they were referred to the TTP or managed through a traditional referral process. Wait times (in days) from first abnormal imaging to biopsy and treatment initiation were recorded. Statistical analysis was performed using the Wilcoxon rank-sum test. A total of 133 patients who met inclusion criteria were identified. Seventy-nine patients were referred to the TTP and 54 were managed by traditional means. There was a statistically significant reduction in median wait times for patients referred to the TTP. Wait time from first abnormal imaging to biopsy decreased from 61.5 to 36.0 days (P < .0001). Wait time from first abnormal imaging to treatment initiation decreased from 118.0 to 80.0 days (P < .001). The percentage of specialist consultations that led to treatment was also greater for patients referred to the TTP. A collaborative, centralized intake and referral program helps to reduce wait time for diagnosis and treatment of lung cancer. Copyright © 2018 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.
A Conceptual Framework for Improving Critical Care Patient Flow and Bed Use.
Mathews, Kusum S; Long, Elisa F
2015-06-01
High demand for intensive care unit (ICU) services and limited bed availability have prompted hospitals to address capacity planning challenges. Simulation modeling can examine ICU bed assignment policies, accounting for patient acuity, to reduce ICU admission delays. To provide a framework for data-driven modeling of ICU patient flow, identify key measurable outcomes, and present illustrative analysis demonstrating the impact of various bed allocation scenarios on outcomes. A description of key inputs for constructing a queuing model was outlined, and an illustrative simulation model was developed to reflect current triage protocol within the medical ICU and step-down unit (SDU) at a single tertiary-care hospital. Patient acuity, arrival rate, and unit length of stay, consisting of a "service time" and "time to transfer," were estimated from 12 months of retrospective data (n = 2,710 adult patients) for 36 ICU and 15 SDU staffed beds. Patient priority was based on acuity and whether the patient originated in the emergency department. The model simulated the following hypothetical scenarios: (1) varied ICU/SDU sizes, (2) reserved ICU beds as a triage strategy, (3) lower targets for time to transfer out of the ICU, and (4) ICU expansion by up to four beds. Outcomes included ICU admission wait times and unit occupancy. With current bed allocation, simulated wait time averaged 1.13 (SD, 1.39) hours. Reallocating all SDU beds as ICU decreased overall wait times by 7.2% to 1.06 (SD, 1.39) hours and increased bed occupancy from 80 to 84%. Reserving the last available bed for acute patients reduced wait times for acute patients from 0.84 (SD, 1.12) to 0.31 (SD, 0.30) hours, but tripled subacute patients' wait times from 1.39 (SD, 1.81) to 4.27 (SD, 5.44) hours. Setting transfer times to wards for all ICU/SDU patients to 1 hour decreased wait times for incoming ICU patients, comparable to building one to two additional ICU beds. Hospital queuing and simulation modeling with empiric data inputs can evaluate how changes in ICU bed assignment could impact unit occupancy levels and patient wait times. Trade-offs associated with dedicating resources for acute patients versus expanding capacity for all patients can be examined.
Yang, Muer; Fry, Michael J; Raikhelkar, Jayashree; Chin, Cynthia; Anyanwu, Anelechi; Brand, Jordan; Scurlock, Corey
2013-02-01
To develop queuing and simulation-based models to understand the relationship between ICU bed availability and operating room schedule to maximize the use of critical care resources and minimize case cancellation while providing equity to patients and surgeons. Retrospective analysis of 6-month unit admission data from a cohort of cardiothoracic surgical patients, to create queuing and simulation-based models of ICU bed flow. Three different admission policies (current admission policy, shortest-processing-time policy, and a dynamic policy) were then analyzed using simulation models, representing 10 yr worth of potential admissions. Important output data consisted of the "average waiting time," a proxy for unit efficiency, and the "maximum waiting time," a surrogate for patient equity. A cardiothoracic surgical ICU in a tertiary center in New York, NY. Six hundred thirty consecutive cardiothoracic surgical patients admitted to the cardiothoracic surgical ICU. None. Although the shortest-processing-time admission policy performs best in terms of unit efficiency (0.4612 days), it did so at expense of patient equity prolonging surgical waiting time by as much as 21 days. The current policy gives the greatest equity but causes inefficiency in unit bed-flow (0.5033 days). The dynamic policy performs at a level (0.4997 days) 8.3% below that of the shortest-processing-time in average waiting time; however, it balances this with greater patient equity (maximum waiting time could be shortened by 4 days compared to the current policy). Queuing theory and computer simulation can be used to model case flow through a cardiothoracic operating room and ICU. A dynamic admission policy that looks at current waiting time and expected ICU length of stay allows for increased equity between patients with only minimum losses of efficiency. This dynamic admission policy would seem to be a superior in maximizing case-flow. These results may be generalized to other surgical ICUs.
Advertising emergency department wait times.
Weiner, Scott G
2013-03-01
Advertising emergency department (ED) wait times has become a common practice in the United States. Proponents of this practice state that it is a powerful marketing strategy that can help steer patients to the ED. Opponents worry about the risk to the public health that arises from a patient with an emergent condition self-triaging to a further hospital, problems with inaccuracy and lack of standard definition of the reported time, and directing lower acuity patients to the higher cost ED setting instead to primary care. Three sample cases demonstrating the pitfalls of advertising ED wait times are discussed. Given the lack of rigorous evidence supporting the practice and potential adverse effects to the public health, caution about its use is advised.
NASA Astrophysics Data System (ADS)
Sazuka, Naoya
2007-03-01
We analyze waiting times for price changes in a foreign currency exchange rate. Recent empirical studies of high-frequency financial data support that trades in financial markets do not follow a Poisson process and the waiting times between trades are not exponentially distributed. Here we show that our data is well approximated by a Weibull distribution rather than an exponential distribution in the non-asymptotic regime. Moreover, we quantitatively evaluate how much an empirical data is far from an exponential distribution using a Weibull fit. Finally, we discuss a transition between a Weibull-law and a power-law in the long time asymptotic regime.
Design of limited-stop service based on the degree of unbalance of passenger demand
2018-01-01
This paper presents a limited-stop service for a bus fleet to meet the unbalanced demand of passengers on a bus route and to improve the transit service of the bus route. This strategy includes two parts: a degree assessment of unbalanced passenger demand and an optimization of the limited-stop service. The degree assessment of unbalanced passenger demand, which is based on the different passenger demand between stations and the unbalance of passengers within the station, is used to judge whether implementing the limited-stop service is necessary for a bus route. The optimization of limited-stop service considers the influence of stop skipping action and bus capacity on the left-over passengers to determine the proper skipping stations for the bus fleet serving the entire route by minimizing both the waiting time and in-vehicle time of passengers and the running time of vehicles. A solution algorithm based on genetic algorithm is also presented to evaluate the degree of unbalanced passenger demand and optimize the limited-stop scheme. Then, the proper strategy is tested on a bus route in Changchun city of China. The threshold of degree assessment of unbalanced passenger demand can be calibrated and adapted to different passenger demands. PMID:29505585
Design of limited-stop service based on the degree of unbalance of passenger demand.
Zhang, Hu; Zhao, Shuzhi; Liu, Huasheng; Liang, Shidong
2018-01-01
This paper presents a limited-stop service for a bus fleet to meet the unbalanced demand of passengers on a bus route and to improve the transit service of the bus route. This strategy includes two parts: a degree assessment of unbalanced passenger demand and an optimization of the limited-stop service. The degree assessment of unbalanced passenger demand, which is based on the different passenger demand between stations and the unbalance of passengers within the station, is used to judge whether implementing the limited-stop service is necessary for a bus route. The optimization of limited-stop service considers the influence of stop skipping action and bus capacity on the left-over passengers to determine the proper skipping stations for the bus fleet serving the entire route by minimizing both the waiting time and in-vehicle time of passengers and the running time of vehicles. A solution algorithm based on genetic algorithm is also presented to evaluate the degree of unbalanced passenger demand and optimize the limited-stop scheme. Then, the proper strategy is tested on a bus route in Changchun city of China. The threshold of degree assessment of unbalanced passenger demand can be calibrated and adapted to different passenger demands.
24 CFR 982.204 - Waiting list: Administration of waiting list.
Code of Federal Regulations, 2010 CFR
2010-04-01
... size (number of bedrooms for which family qualifies under PHA occupancy standards); (3) Date and time... list. (d) Family size. (1) The order of admission from the waiting list may not be based on family size, or on the family unit size for which the family qualifies under the PHA occupancy policy. (2) If the...
An analytical study of various telecomminication networks using markov models
NASA Astrophysics Data System (ADS)
Ramakrishnan, M.; Jayamani, E.; Ezhumalai, P.
2015-04-01
The main aim of this paper is to examine issues relating to the performance of various Telecommunication networks, and applied queuing theory for better design and improved efficiency. Firstly, giving an analytical study of queues deals with quantifying the phenomenon of waiting lines using representative measures of performances, such as average queue length (on average number of customers in the queue), average waiting time in queue (on average time to wait) and average facility utilization (proportion of time the service facility is in use). In the second, using Matlab simulator, summarizes the finding of the investigations, from which and where we obtain results and describing methodology for a) compare the waiting time and average number of messages in the queue in M/M/1 and M/M/2 queues b) Compare the performance of M/M/1 and M/D/1 queues and study the effect of increasing the number of servers on the blocking probability M/M/k/k queue model.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, C.; Su, W.; Fang, C.
2014-09-10
We present a study of the waiting time distributions (WTDs) of solar energetic particle (SEP) events observed with the spacecraft WIND and GOES. The WTDs of both solar electron events (SEEs) and solar proton events (SPEs) display a power-law tail of ∼Δt {sup –γ}. The SEEs display a broken power-law WTD. The power-law index is γ{sub 1} = 0.99 for the short waiting times (<70 hr) and γ{sub 2} = 1.92 for large waiting times (>100 hr). The break of the WTD of SEEs is probably due to the modulation of the corotating interaction regions. The power-law index, γ ∼more » 1.82, is derived for the WTD of the SPEs which is consistent with the WTD of type II radio bursts, indicating a close relationship between the shock wave and the production of energetic protons. The WTDs of SEP events can be modeled with a non-stationary Poisson process, which was proposed to understand the waiting time statistics of solar flares. We generalize the method and find that, if the SEP event rate λ = 1/Δt varies as the time distribution of event rate f(λ) = Aλ{sup –α}exp (– βλ), the time-dependent Poisson distribution can produce a power-law tail WTD of ∼Δt {sup α} {sup –3}, where 0 ≤ α < 2.« less
Effect of self-triage on waiting times at a walk-in sexual health clinic.
Hitchings, Samantha; Barter, Janet
2009-10-01
Lengthy waiting times can be a major problem in walk-in sexual health clinics. They are stressful for both patients and staff and may lead to clients with significant health issues leaving the department before being seen by a clinician. A self-triage system may help reduce waiting times and duplication of work, improve patient pathways and decrease wasted visits. This paper describes implementation of a self-triage system in two busy sexual and reproductive health clinics. Patients were asked to complete a self-assessment form on registration to determine the reason for attendance. This then enabled patients to be directed to the most appropriate specialist or clinical service. The benefits of this approach were determined by measuring patient waiting times, reduction in unnecessary specialist review together with patient acceptability as tested by a patient satisfaction survey. The ease of comprehension of the triage form was also assessed by an independent readers' panel. A total of 193 patients were recruited over a 4-month period from November 2004 to February 2005. Patients from the November and December clinics were assigned to the 'traditional treatment' arm, with patients at subsequent clinics being assigned to the 'self-triage' system. Waiting times were collected by the receptionist and clinic staff. Ninety six patients followed the traditional route, 97 the new self-triage system. Sixty-nine (35.8%) patients completed the satisfaction survey. The self-triage system significantly reduced waiting time from 40 (22, 60) to 23 (10, 40) minutes [results expressed as median (interquartile range)]. There was a non-significant reduction in the proportion of patients seeing two clinicians from 21% to 13% (p = 0.17). Satisfaction levels were not significantly altered (95% compared to 97% satisfied, p = 0.64). The readers' panel found the triage form both easy to understand and to complete. Self-triage can effectively reduce clinic waiting times and allow better organisation of resources. Urgent cases can be prioritised. This process appears to be acceptable to and understandable by patients.
Waiting for the right time: how and why young Thai women manage to avoid heterosexual intercourse.
Supametaporn, Pinhatai; Stern, Phyllis Noerager; Rodcumdee, Branom; Chaiyawat, Waraporn
2010-08-01
Nineteen young Thai women were purposively selected from networks of nongovernmental organizations involving children and youths in Bangkok. Our grounded theory findings indicated that these young women used the basic social process they called "waiting for the right time" in order to maintain heterosexual abstinence. Waiting for the right time involved one overarching condition, honoring parental love, and included three overlapping properties: learning rules, planning life path, and ways of preserving virginity. The findings provide information that may lead to the development of culturally competent interventions for middle-class Thai youths to remain healthy and avoid pregnancy.
The impact of the lung allocation score on short-term transplantation outcomes: a multicenter study.
Kozower, Benjamin D; Meyers, Bryan F; Smith, Michael A; De Oliveira, Nilto C; Cassivi, Stephen D; Guthrie, Tracey J; Wang, Honkung; Ryan, Beverly J; Shen, K Robert; Daniel, Thomas M; Jones, David R
2008-01-01
The lung allocation score restructured the distribution of scarce donor lungs for transplantation. The algorithm ranks waiting list patients according to medical urgency and expected benefit after transplantation. The purpose of this study was to evaluate the impact of the lung allocation score on short-term outcomes after lung transplantation. A multicenter retrospective cohort study was performed with data from 5 academic medical centers. Results of patients undergoing transplantation on the basis of the lung allocation score (May 4, 2005 to May 3, 2006) were compared with those of patients receiving transplants the preceding year before the lung allocation score was implemented (May 4, 2004, to May 3, 2005). The study reports on 341 patients (170 before the lung allocation score and 171 after). Waiting time decreased from 680.9 +/- 528.3 days to 445.6 +/- 516.9 days (P < .001). Recipient diagnoses changed with an increase in idiopathic pulmonary fibrosis and a decrease in emphysema and cystic fibrosis (P = .002). Postoperatively, primary graft dysfunction increased from 14.1% (24/170) to 22.9% (39/171) (P = .04) and intensive care unit length of stay increased from 5.7 +/- 6.7 days to 7.8 +/- 9.6 days (P = .04). Hospital mortality and 1-year survival were the same between groups (5.3% vs 5.3% and 90% vs 89%, respectively; P > .6) This multicenter retrospective review of short-term outcomes supports the fact that the lung allocation score is achieving its objectives. The lung allocation score reduced waiting time and altered the distribution of lung diseases for which transplantation was done on the basis of medical necessity. After transplantation, recipients have significantly higher rates of primary graft dysfunction and intensive care unit lengths of stay. However, hospital mortality and 1-year survival have not been adversely affected.
Hanauer, D.A.
2014-01-01
Summary Background Patient no-shows in outpatient delivery systems remain problematic. The negative impacts include underutilized medical resources, increased healthcare costs, decreased access to care, and reduced clinic efficiency and provider productivity. Objective To develop an evidence-based predictive model for patient no-shows, and thus improve overbooking approaches in outpatient settings to reduce the negative impact of no-shows. Methods Ten years of retrospective data were extracted from a scheduling system and an electronic health record system from a single general pediatrics clinic, consisting of 7,988 distinct patients and 104,799 visits along with variables regarding appointment characteristics, patient demographics, and insurance information. Descriptive statistics were used to explore the impact of variables on show or no-show status. Logistic regression was used to develop a no-show predictive model, which was then used to construct an algorithm to determine the no-show threshold that calculates a predicted show/no-show status. This approach aims to overbook an appointment where a scheduled patient is predicted to be a no-show. The approach was compared with two commonly-used overbooking approaches to demonstrate the effectiveness in terms of patient wait time, physician idle time, overtime and total cost. Results From the training dataset, the optimal error rate is 10.6% with a no-show threshold being 0.74. This threshold successfully predicts the validation dataset with an error rate of 13.9%. The proposed overbooking approach demonstrated a significant reduction of at least 6% on patient waiting, 27% on overtime, and 3% on total costs compared to other common flat-overbooking methods. Conclusions This paper demonstrates an alternative way to accommodate overbooking, accounting for the prediction of an individual patient’s show/no-show status. The predictive no-show model leads to a dynamic overbooking policy that could improve patient waiting, overtime, and total costs in a clinic day while maintaining a full scheduling capacity. PMID:25298821
The Optimal Observation Problem applied to a rating curve estimation including the "cost-to-wait"
NASA Astrophysics Data System (ADS)
Raso, Luciano; Werner, Micha; Weijs, Steven
2013-04-01
In order to manage a system, a decision maker (DM) tries to make the best decision under uncertainty, having partial knowledge on the effects of his/her decision. Observations reduce uncertainty, but are costly. Deciding what to observe and when to stop observing is a complementary problem that the DM has to face. The Optimal Observation Problem (OOP) offers a solution to the questions: (1) which observation is more effective? And (2) Is the next observation worth its cost? We show an application of the OOP to a rating curve estimation in the White Carter River (Scotland). The cost of extra gauging is compensated by the value of better decisions, that reduce the costs due to floods. The observational decision is then whether to gauge, and when. In the application, we include the "cost-to-wait" in the cost structure. The Algorithm find thus an optimal trade-off between getting less informative data now or wait for more informative, but later. The OOP can be used to plan a measurement campaign, also taking into account that the rating curve can change.
DOT National Transportation Integrated Search
2013-08-01
Pilots thatuse an impairing medication to treat a medicalcondition are required to wait an appropriate amount of time after completing the treatment before returning to duty.However, toxicology findings for pilots involved in fatal aviation accidents...
Waiting time for radiotherapy in women with cervical cancer
do Nascimento, Maria Isabel; Azevedo e Silva, Gulnar
2016-01-01
ABSTRACT OBJECTIVE To describe the waiting time for radiotherapy for patients with cervical cancer. METHODS This descriptive study was conducted with 342 cervical cancer cases that were referred to primary radiotherapy, in the Baixada Fluminense region, RJ, Southeastern Brazil, from October 1995 to August 2010. The waiting time was calculated using the recommended 60-day deadline as a parameter to obtaining the first cancer treatment and considering the date at which the diagnosis was confirmed, the date of first oncological consultation and date when the radiotherapy began. Median and proportional comparisons were made using the Kruskal Wallis and Chi-square tests. RESULTS Most of the women (72.2%) began their radiotherapy within 60 days from the diagnostic confirmation date. The median of this total waiting time was 41 days. This median worsened over the time period, going from 11 days (1995-1996) to 64 days (2009-2010). The median interval between the diagnostic confirmation and the first oncological consultation was 33 days, and between the first oncological consultation and the first radiotherapy session was four days. The median waiting time differed significantly (p = 0.003) according to different stages of the tumor, reaching 56 days, 35 days and 30 days for women whose cancers were classified up to IIA; from IIB to IIIB, and IVA-IVB, respectively. CONCLUSIONS Despite most of the women having had access to radiotherapy within the recommended 60 days, the implementation of procedures to define the stage of the tumor and to reestablish clinical conditions took a large part of this time, showing that at least one of these intervals needs to be improved. Even though the waiting times were ideal for all patients, the most advanced cases were quickly treated, which suggests that access to radiotherapy by women with cervical cancer has been reached with equity. PMID:26786473
The impact of diagnostic imaging wait times on the prognosis of lung cancer.
Byrne, Suzanne C; Barrett, Brendan; Bhatia, Rick
2015-02-01
This study was performed to determine whether gaps in patient flow from initial lung imaging to computed tomography (CT) guided lung biopsy in patients with non-small cell lung cancer (NSCLC) was associated with a change in tumour size, stage, and thus prognosis. All patients who had a CT-guided lung biopsy in 2009 (phase I) and in 2011 (phase II) with a pathologic diagnosis of primary lung cancer (NSCLC) at Eastern Health, Newfoundland, were identified. Dates of initial abnormal imaging, confirmatory CT (if performed), and CT-guided biopsy were recorded, along with tumour size and resulting T stage at each time point. In 2010, wait times for diagnostic imaging at Eastern Health were reduced. The stage and prognosis of NSCLC in 2009 was compared with 2011. In phase 1, there was a statistically significant increase in tumour size (mean difference, 0.67 cm; P < .0001) and stage (P < .0001) from initial image to biopsy. There was a moderate correlation between the time (in days) between the images and change in size (r = 0.33, P = .008) or stage (r = 0.26, P = .036). In phase II, the median wait time from initial imaging to confirmatory CT was reduced to 7.5 days (from 19 days). At this reduced wait time, there was no statistically significant increase in tumour size (mean difference, 0.02; P > .05) or stage (P > .05) from initial imaging to confirmatory CT. Delays in patient flow through diagnostic imaging resulted in an increase in tumour size and stage, with a negative impact on prognosis of NSCLC. This information contributed to the hiring of additional CT technologists and extended CT hours to decrease the wait time for diagnostic imaging. With reduced wait times, the prognosis of NSCLC was not adversely impacted as patients navigated through diagnostic imaging. Copyright © 2015 Canadian Association of Radiologists. All rights reserved.
Walking Clinic in ambulatory surgery--A patient based concept: A Portuguese pioneer project.
Vinagreiro, M; Valverde, J N; Alves, D; Costa, M; Gouveia, P; Guerreiro, E
2015-06-01
Walking Clinic is an innovative, efficient and easily reproducible concept adapted to ambulatory surgery. It consists of a preoperative single day work-up, with a surgeon, an anesthetist and a nurse. The aim of this study was to evaluate patient satisfaction and its determinants. A survey was applied to 171 patients (101 of the Walking Clinic group and 70 not engaged in this new concept). Patient satisfaction was assessed evaluating five major questionnaire items: secretariat (quality of the information and support given), physical space (overall comfort and cleanliness), nurses and medical staff (willingness and expertise), and patients (waiting time until pre-operative consults and exams, waiting time until being scheduled for surgery, surgery day waiting time and postoperative pain control). Furthermore, overall assessment of the received treatment, and probability of patient recommending or returning to our ambulatory unit were also analyzed. Walking Clinic group had overall better results in the five major questionnaire items assessed, with statistical significance, except for the physical space. It also showed better results regarding the sub-items postoperative pain control, waiting time until being scheduled for surgery and surgery day waiting time. The results confirm better patient satisfaction with this new concept. The Walking Clinic concept complements all the tenets of ambulatory surgery, in a more efficient manner. Copyright © 2015 IJS Publishing Group Limited. Published by Elsevier Ltd. All rights reserved.
Waiting for hip arthroplasty: economic costs and health outcomes.
Fielden, Jann M; Cumming, J M; Horne, J G; Devane, P A; Slack, A; Gallagher, L M
2005-12-01
This prospective cohort study of 153 patients aimed to determine the economic and health costs of waiting for total hip arthroplasty (THA). Health-related quality of life, using self-completed WOMAC and EQ-5D questionnaires, was assessed monthly from enrolment preoperatively to 6 months postsurgery. Monthly cost diaries were used to record costs. The mean waiting time was 5.1 months and mean total cost of waiting for surgery was NZ 4305 dollars(US 2876 dollars) per person (pp) (NZ 1 dollar = US 0.668 dollar). Waiting more than 6 months was associated with a higher total mean cost (NZ 4278 dollars/US 2858 dollars pp) than waiting less than 6 months (NZ 2828 dollars/US 1889 dollars pp; P < .01). Improvements from preoperative to postoperative WOMAC and EQ-5D scores were identified (P < or = .01). Waiting longer led to poorer physical function preoperatively (P < or = .01). Those with poor initial health status showed greater improvement in WOMAC (P = .0001) and EQ-5D (P = .003) measures by 6 months after surgery. Longer waits for total hip arthroplasty incur greater economic costs and deterioration in physical function while waiting.
Zhao, Shuzhen; He, Lujia; Feng, Chenchen; He, Xiaoli
2018-06-01
Laboratory errors in blood collection center (BCC) are most common in the preanalytical phase. It is, therefore, of vital importance for administrators to take measures to improve healthcare quality and patient safety.In 2015, a case bundle management strategy was applied in a large outpatient BCC to improve its medical quality and patient safety.Unqualified blood sampling, complications, patient waiting time, largest number of patients waiting during peak hours, patient complaints, and patient satisfaction were compared over the period from 2014 to 2016.The strategy reduced unqualified blood sampling, complications, patient waiting time, largest number of patients waiting during peak hours, and patient complaints, while improving patient satisfaction.This strategy was effective in improving BCC healthcare quality and patient safety.
DOT National Transportation Integrated Search
2015-11-01
The Arizona Department of Transportation (ADOT), Office of P3 Initiatives and International : Affairs selected Lee Engineering to analyze the penetration rate of Anonymous Re-Identification : (ARID) technology to measure wait time of U.S. and Mexico ...
NASA Astrophysics Data System (ADS)
Cincotti, Silvano; Ponta, Linda; Raberto, Marco; Scalas, Enrico
2005-05-01
In this paper, empirical analyses and computational experiments are presented on high-frequency data for a double-auction (book) market. Main objective of the paper is to generalize the order waiting time process in order to properly model such empirical evidences. The empirical study is performed on the best bid and best ask data of 7 U.S. financial markets, for 30-stock time series. In particular, statistical properties of trading waiting times have been analyzed and quality of fits is evaluated by suitable statistical tests, i.e., comparing empirical distributions with theoretical models. Starting from the statistical studies on real data, attention has been focused on the reproducibility of such results in an artificial market. The computational experiments have been performed within the Genoa Artificial Stock Market. In the market model, heterogeneous agents trade one risky asset in exchange for cash. Agents have zero intelligence and issue random limit or market orders depending on their budget constraints. The price is cleared by means of a limit order book. The order generation is modelled with a renewal process. Based on empirical trading estimation, the distribution of waiting times between two consecutive orders is modelled by a mixture of exponential processes. Results show that the empirical waiting-time distribution can be considered as a generalization of a Poisson process. Moreover, the renewal process can approximate real data and implementation on the artificial stocks market can reproduce the trading activity in a realistic way.
Advertising Emergency Department Wait Times
Weiner, Scott G.
2013-01-01
Advertising emergency department (ED) wait times has become a common practice in the United States. Proponents of this practice state that it is a powerful marketing strategy that can help steer patients to the ED. Opponents worry about the risk to the public health that arises from a patient with an emergent condition self-triaging to a further hospital, problems with inaccuracy and lack of standard definition of the reported time, and directing lower acuity patients to the higher cost ED setting instead to primary care. Three sample cases demonstrating the pitfalls of advertising ED wait times are discussed. Given the lack of rigorous evidence supporting the practice and potential adverse effects to the public health, caution about its use is advised. PMID:23599836
Optogenetic activation of dorsal raphe serotonin neurons enhances patience for future rewards.
Miyazaki, Kayoko W; Miyazaki, Katsuhiko; Tanaka, Kenji F; Yamanaka, Akihiro; Takahashi, Aki; Tabuchi, Sawako; Doya, Kenji
2014-09-08
Serotonin is a neuromodulator that is involved extensively in behavioral, affective, and cognitive functions in the brain. Previous recording studies of the midbrain dorsal raphe nucleus (DRN) revealed that the activation of putative serotonin neurons correlates with the levels of behavioral arousal [1], rhythmic motor outputs [2], salient sensory stimuli [3-6], reward, and conditioned cues [5-8]. The classic theory on serotonin states that it opposes dopamine and inhibits behaviors when aversive events are predicted [9-14]. However, the therapeutic effects of serotonin signal-enhancing medications have been difficult to reconcile with this theory [15, 16]. In contrast, a more recent theory states that serotonin facilitates long-term optimal behaviors and suppresses impulsive behaviors [17-21]. To test these theories, we developed optogenetic mice that selectively express channelrhodopsin in serotonin neurons and tested how the activation of serotonergic neurons in the DRN affects animal behavior during a delayed reward task. The activation of serotonin neurons reduced the premature cessation of waiting for conditioned cues and food rewards. In reward omission trials, serotonin neuron stimulation prolonged the time animals spent waiting. This effect was observed specifically when the animal was engaged in deciding whether to keep waiting and was not due to motor inhibition. Control experiments showed that the prolonged waiting times observed with optogenetic stimulation were not due to behavioral inhibition or the reinforcing effects of serotonergic activation. These results show, for the first time, that the timed activation of serotonin neurons during waiting promotes animals' patience to wait for a delayed reward. Copyright © 2014 Elsevier Ltd. All rights reserved.
Ju, Lining; Wang, Yijie Dylan; Hung, Ying; Wu, Chien-Fu Jeff; Zhu, Cheng
2013-01-01
Motivation: Abrupt reduction/resumption of thermal fluctuations of a force probe has been used to identify association/dissociation events of protein–ligand bonds. We show that off-rate of molecular dissociation can be estimated by the analysis of the bond lifetime, while the on-rate of molecular association can be estimated by the analysis of the waiting time between two neighboring bond events. However, the analysis relies heavily on subjective judgments and is time-consuming. To automate the process of mapping out bond events from thermal fluctuation data, we develop a hidden Markov model (HMM)-based method. Results: The HMM method represents the bond state by a hidden variable with two values: bound and unbound. The bond association/dissociation is visualized and pinpointed. We apply the method to analyze a key receptor–ligand interaction in the early stage of hemostasis and thrombosis: the von Willebrand factor (VWF) binding to platelet glycoprotein Ibα (GPIbα). The numbers of bond lifetime and waiting time events estimated by the HMM are much more than those estimated by a descriptive statistical method from the same set of raw data. The kinetic parameters estimated by the HMM are in excellent agreement with those by a descriptive statistical analysis, but have much smaller errors for both wild-type and two mutant VWF-A1 domains. Thus, the computerized analysis allows us to speed up the analysis and improve the quality of estimates of receptor–ligand binding kinetics. Contact: jeffwu@isye.gatech.edu or cheng.zhu@bme.gatech.edu PMID:23599504
Bobrovitz, Niklas; Lasserson, Daniel S; Briggs, Adam D M
2017-11-02
The four-hour target is a key hospital emergency department performance indicator in England and one that drives the physical and organisational design of the ED. Some studies have identified time of presentation as a key factor affecting waiting times. Few studies have investigated other determinants of breaching the four-hour target. Therefore, our objective was to describe patterns of emergency department breaches of the four-hour wait time target and identify patients at highest risk of breaching. This was a retrospective cohort study of a large type 1 Emergency department at an NHS teaching hospital in Oxford, England. We analysed anonymised individual level patient data for 378,873 emergency department attendances, representing all attendances between April 2008 and April 2013. We examined patient characteristics and emergency department presentation circumstances associated with the highest likelihood of breaching the four-hour wait time target. We used 374,459 complete cases for analysis. In total, 8.3% of all patients breached the four-hour wait time target. The main determinants of patients breaching the four-hour wait time target were hour of arrival to the ED, day of the week, patient age, ED referral source, and the types of investigations patients receive (p < 0.01 for all associations). Patients most likely to breach the four-hour target were older, presented at night, presented on Monday, received multiple types of investigation in the emergency department, and were not self-referred (p < 0.01 for all associations). Patients attending from October to February had a higher odds of breaching compared to those attending from March to September (OR 1.63, 95% CI 1.59 to 1.66). There are a number of independent patient and circumstantial factors associated with the probability of breaching the four-hour ED wait time target including patient age, ED referral source, the types of investigations patients receive, as well as the hour, day, and month of arrival to the ED. Efforts to reduce the number of breaches could explore late-evening/overnight staffing, access to diagnostic tests, rapid discharge facilities, and early assessment and input on diagnostic and management strategies from a senior practitioner.
Time Spent in Indirect Nursing Care
1983-09-01
divisions of labor by nursing personnel: a) direct patient care (28-35%); b) indirect care (50-62%); and c) personal time (10-15%). In comparing the... personal time (13-18%) (Kuhn, 1983). It must be noted that, in the VA data, wait time (time waiting to render care) has been subsumed under personal time...interval during the entire eight-hour shift. The first task observed being performed by the monitored person was the activity documented. 5 U. ,. 1 -V
C3PO - A Dynamic Data Placement Agent for ATLAS Distributed Data Management
NASA Astrophysics Data System (ADS)
Beermann, T.; Lassnig, M.; Barisits, M.; Serfon, C.; Garonne, V.; ATLAS Collaboration
2017-10-01
This paper introduces a new dynamic data placement agent for the ATLAS distributed data management system. This agent is designed to pre-place potentially popular data to make it more widely available. It therefore incorporates information from a variety of sources. Those include input datasets and sites workload information from the ATLAS workload management system, network metrics from different sources like FTS and PerfSonar, historical popularity data collected through a tracer mechanism and more. With this data it decides if, when and where to place new replicas that then can be used by the WMS to distribute the workload more evenly over available computing resources and then ultimately reduce job waiting times. This paper gives an overview of the architecture and the final implementation of this new agent. The paper also includes an evaluation of the placement algorithm by comparing the transfer times and the new replica usage.
A comparison of control modes for time-delayed remote manipulation
NASA Technical Reports Server (NTRS)
Starr, G. P.
1982-01-01
Transmission time delay in the communication channel of a manual control system is investigated. A time delay can exist in remote manipulation systems, caused by long communication distances or bandwidth limitations. Ferrell 1 conducted the first research in time-delayed manipulation using a two degree-of-freedom manipulator. His subjects, working at time delays of 1.0, 2.1, and 3.2 s, could accomplish tasks even requiring great accuracy. The subjects spontaneously adopted a pattern of moving cautiously, then waiting to see the results of their actions. In experiments with a six degree-of-freedom master-slave manipulator system and time delays of 1.0 to 6 s, Black 2 saw that subjects tried to use the move-and-wait strategy; but there were often difficulties. The subjects seemed to have a problem in holding the master arm stationary while waiting for feedback. Any undesired drifting of the master arm introduced a discrepancy between the positions of the master and slave. This discrepancy was not perceived because of the time delay. The subject would then begin his next move with an inherent error. The difficulty of effectively using the move-and-wait strategy with a master-slave manipulator suggested that rate control might be a more effective control mode with time delay.
A new approach for the assessment of temporal clustering of extratropical wind storms
NASA Astrophysics Data System (ADS)
Schuster, Mareike; Eddounia, Fadoua; Kuhnel, Ivan; Ulbrich, Uwe
2017-04-01
A widely-used methodology to assess the clustering of storms in a region is based on dispersion statistics of a simple homogeneous Poisson process. This clustering measure is determined by the ratio of the variance and the mean of the local storm statistics per grid point. Resulting values larger than 1, i.e. when the variance is larger than the mean, indicate clustering; while values lower than 1 indicate a sequencing of storms that is more regular than a random process. However, a disadvantage of this methodology is that the characteristics are valid for a pre-defined climatological time period, and it is not possible to identify a temporal variability of clustering. Also, the absolute value of the dispersion statistics is not particularly intuitive. We have developed an approach to describe temporal clustering of storms which offers a more intuitive comprehension, and at the same time allows to assess temporal variations. The approach is based on the local distribution of waiting times between the occurrence of two individual storm events, the former being computed through the post-processing of individual windstorm tracks which in turn are obtained by an objective tracking algorithm. Based on this distribution a threshold can be set, either by the waiting time expected from a random process or by a quantile of the observed distribution. Thus, it can be determined if two consecutive wind storm events count as part of a (temporal) cluster. We analyze extratropical wind storms in a reanalysis dataset and compare the results of the traditional clustering measure with our new methodology. We assess what range of clustering events (in terms of duration and frequency) is covered and identify if the historically known clustered seasons are detectable by the new clustering measure in the reanalysis.
Development of an Information Model for Kidney Transplant Wait List.
Bircan, Hüseyin Yüce; Özçelik, Ümit; Uysal, Nida; Demirağ, Alp; Haberal, Mehmet
2015-11-01
Deceased-donor kidney transplant is unique among surgical procedures that are an urgent procedure performed in an elective population. It has not been possible to accurately determine when a given patient will be called for transplant. Patients on the active transplant list can be called for a transplant at any time. As a result, every effort must be made to optimize their health according to best practices and published clinical practice guidelines. Once the patient is placed on the transplant wait list after undergoing an initial extensive evaluation, continued surveillance is required. Therefore, we developed a kidney transplant wait list surveillance software program that alerts organ transplant coordinator on time regarding which patients need a work-up. The new designed software has a database of our waiting patients with their completed and pending controls. The software also has built-in functions to warn the responsible staff with an E-mail. If one of the controls of a recipient delayed, the software sends an automated E-mail to the staff regarding the patients delayed controls. The software is a Web application that works on any platform with a Web browser and Internet connection and allows access by multiple users. The software has been developed with NET platform. The database is SQL server. The software has the following functions: patient communication info, search, alert list, alert E-mail, control entry, and system management. As of January 2014, a total of 21 000 patients were registered on the National Kidney Transplant wait list in Turkey and the kidney transplant wait list had been expanding by 2000 to 3000 patients each year. Therefore computerized wait list programs are crucial to help to transplant centers to keep their patients up-to-date on time.
The effect of waiting: A meta-analysis of wait-list control groups in trials for tinnitus distress.
Hesser, Hugo; Weise, Cornelia; Rief, Winfried; Andersson, Gerhard
2011-04-01
The response rates and effects of being placed on a wait-list control condition are well documented in psychiatric populations. Despite the usefulness of such estimates and the frequent use of no-treatment controls in clinical trials for tinnitus, the effect of waiting in a tinnitus trial has not been investigated systematically. The aim of the present study was to quantify the overall effect of wait-list control groups on tinnitus distress. Studies were retrieved via a systematic review of randomised controlled trials of cognitive behaviour therapy for tinnitus distress. Outcomes of psychometrically robust tinnitus-specific measures (Tinnitus Handicap Inventory, Tinnitus Questionnaire, Tinnitus Reaction Questionnaire) from wait-list control groups were quantified using meta-analytic techniques. Percentage of change and standard mean difference effect sizes were calculated using the pre and post wait period. Eleven studies involving 314 wait-list subjects with tinnitus were located. The analysis for a waiting period of 6 to 12 weeks revealed a mean decrease in scores on tinnitus-specific measures of 3% to 8%. Across studies, a statically significant small mean within-group effect size was obtained (Hedges' g=.17). The effects were moderated by methodological quality of the trial, sample characteristics (i.e., age, tinnitus duration), time of the wait-list and how diagnosis was established. Subjects in a tinnitus trial improve in tinnitus distress over a short waiting phase. The effects of waiting are highly variable and depend on the characteristics of the sample and of the trial. Copyright © 2011 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Galaviz, V. E.; Yost, M. G.; Simpson, C. D.; Camp, J. E.; Paulsen, M. H.; Elder, J. P.; Hoffman, L.; Flores, D.; Quintana, P. J. E.
2014-05-01
Pedestrians waiting to cross into the US from Mexico at Ports of Entry experience long wait times near idling vehicles. The near-road environment is associated with elevated pollutant levels and adverse health outcomes. This is the first exposure assessment conducted to quantify northbound pedestrian commuter exposure to traffic-related air pollutants at the U.S.-Mexico border San Ysidro Port of Entry (SYPOE). Seventy-three persons who regularly crossed the SYPOE in the pedestrian line and 18 persons who did not cross were recruited to wear personal air monitors for 24-h to measure traffic pollutants particulate matter less than 2.5 μm (PM2.5), 1-nitropyrene (1-NP) - a marker for diesel exhaust - and carbon monoxide (CO). Fixed site concentrations were collected at SYPOE and occurred during the time subjects were crossing northbound to approximate their exposure to 1-NP, ultrafine particles (UFP), PM2.5, CO, and black carbon (BC) while standing in line during their border wait. Subjects who crossed the border in pedestrian lanes had a 6-fold increase in exposure to 1-NP, a 3-fold increase in exposure to CO, and a 2-fold increase in exposure to gravimetric PM2.5, vs. non-border commuters. Univariate regression analysis for UFP (median 40,000 # cm-3) found that border wait time for vehicles explained 21% of variability and relative humidity 13%, but when modeled together neither predictor remained significant. Concentrations at the SYPOE of UFP, PM2.5, CO, and BC are similar to those in other near-roadway studies that show associations with acute and chronic adverse health effects. Although results are limited by small sample numbers, these findings warrant concern for adverse health effects experienced by pedestrian commuters waiting in a long northbound queue at SYPOE and demonstrates a potential health benefit of reduced wait times at the border.
Hybrid stochastic simplifications for multiscale gene networks
Crudu, Alina; Debussche, Arnaud; Radulescu, Ovidiu
2009-01-01
Background Stochastic simulation of gene networks by Markov processes has important applications in molecular biology. The complexity of exact simulation algorithms scales with the number of discrete jumps to be performed. Approximate schemes reduce the computational time by reducing the number of simulated discrete events. Also, answering important questions about the relation between network topology and intrinsic noise generation and propagation should be based on general mathematical results. These general results are difficult to obtain for exact models. Results We propose a unified framework for hybrid simplifications of Markov models of multiscale stochastic gene networks dynamics. We discuss several possible hybrid simplifications, and provide algorithms to obtain them from pure jump processes. In hybrid simplifications, some components are discrete and evolve by jumps, while other components are continuous. Hybrid simplifications are obtained by partial Kramers-Moyal expansion [1-3] which is equivalent to the application of the central limit theorem to a sub-model. By averaging and variable aggregation we drastically reduce simulation time and eliminate non-critical reactions. Hybrid and averaged simplifications can be used for more effective simulation algorithms and for obtaining general design principles relating noise to topology and time scales. The simplified models reproduce with good accuracy the stochastic properties of the gene networks, including waiting times in intermittence phenomena, fluctuation amplitudes and stationary distributions. The methods are illustrated on several gene network examples. Conclusion Hybrid simplifications can be used for onion-like (multi-layered) approaches to multi-scale biochemical systems, in which various descriptions are used at various scales. Sets of discrete and continuous variables are treated with different methods and are coupled together in a physically justified approach. PMID:19735554
NASA Astrophysics Data System (ADS)
Ismail, Zurina; Shokor, Shahrul Suhaimi AB
2016-03-01
Rapid life time change of the Malaysian lifestyle had served the overwhelming growth in the service operation industry. On that occasion, this paper will provide the idea to improve the waiting line system (WLS) practices in Malaysia fast food chains. The study will compare the results in between the single server single phase (SSSP) and the single server multi-phase (SSMP) which providing Markovian Queuing (MQ) to be used for analysis. The new system will improve the current WLS, plus intensifying the organization performance. This new WLS were designed and tested in a real case scenario and in order to develop and implemented the new styles, it need to be focusing on the average number of customers (ANC), average number of customer spending time waiting in line (ACS), and the average time customers spend in waiting and being served (ABS). We introduced new WLS design and there will be prompt discussion upon theories of benefits and potential issues that will benefit other researchers.
Low, Lee-Fay; Fletcher, Jennifer; Gresham, Meredith; Brodaty, Henry
2015-09-01
Investigate factors associated with waiting times for home care packages and outcomes for care recipients and carers. Analyses of data collected every four months for 12 months from 55 community-dwelling older adults eligible for government-subsidised packaged care and their carers. Thirty of fifty-five participants were offered a package; they waited from one to 237 days. Baseline quality of life was higher for those offered a package than those not. Baseline care needs and unmet needs, neuropsychiatric symptoms, and cognitive decline did not predict offers. Package receipt compared to non-package receipt was associated with decreased carer burden over time but did not affect levels of unmet care needs, care needs or quality of life. Being offered a home care package was not based on waiting time or unmet care needs. Reforms should include a transparent system of wait listing and prioritisation. © 2014 ACOTA.
Samrsla, Mônica; Nunes, Juliana Cezar; Kalume, Carolina; da Cunha, Antônio Carlos Rodrigues; Garrafa, Volnei
2007-01-01
To analyze the expectations of women who wait for Assisted Reproduction Treatment-RA in the public hospital chosen as the reference in the Public Health Network in the Federal District-HRAS, Brazil. For thirty days, 51 women of the 56 who went to the HRAS for infertility treatment were interviewed by a questionnaire including 10 objective questions related to the topic. This trial was divided into two groups. The first, the "control group", comprised 27 patients recently sent to the reference public hospital from local health care centers or a regional hospital. The second, the "study group", comprising 24 women already diagnosed by the medical staff of HRAS and in the waiting line for "in vitro" fertilization. According to the input provided by the two groups, results show that the average waiting time for treatment is so long that women actually age during this time and face the risk of having a dangerous pregnancy before they receive treatment. These results show that women unable to pay for treatment in a private fertilization clinic have a poorer chance of achieving RA: the health problem concerning this specific population ignores redressing or income distribution processes. Data show that, notwithstanding, this waiting period imposed by the State, expectations of the patients waiting for RA are reinforced. There is no basis to provide information about the waiting time. The unpredictable availability of the medication needed for in vitro fertilization, jeopardizes the future of this service offering the treatment.
Yang, Xiaobao; Huan, Mei; Abdel-Aty, Mohamed; Peng, Yichuan; Gao, Ziyou
2015-01-01
This paper presents a hazard-based duration approach to investigate riders' waiting times, violation hazards, associated risk factors, and their differences between cyclists and electric bike riders at signalized intersections. A total of 2322 two-wheeled riders approaching the intersections during red light periods were observed in Beijing, China. The data were classified into censored and uncensored data to distinguish between safe crossing and red-light running behavior. The results indicated that the red-light crossing behavior of most riders was dependent on waiting time. They were inclined to terminate waiting behavior and run against the traffic light with the increase of waiting duration. Over half of the observed riders cannot endure 49s or longer. 25% of the riders can endure 97s or longer. Rider type, gender, waiting position, conformity tendency and crossing traffic volume were identified to have significant effects on riders' waiting times and violation hazards. Electric bike riders were found to be more sensitive to the external risk factors such as other riders' crossing behavior and crossing traffic volume than cyclists. Moreover, unobserved heterogeneity was examined in the proposed models. The finding of this paper can explain when and why cyclists and electric bike riders run against the red light at intersections. The results of this paper are useful for traffic design and management agencies to implement strategies to enhance the safety of riders. Copyright © 2014 Elsevier Ltd. All rights reserved.
A study on the impact of prioritising emergency department arrivals on the patient waiting time.
Van Bockstal, Ellen; Maenhout, Broos
2018-05-03
In the past decade, the crowding of the emergency department has gained considerable attention of researchers as the number of medical service providers is typically insufficient to fulfil the demand for emergency care. In this paper, we solve the stochastic emergency department workforce planning problem and consider the planning of nurses and physicians simultaneously for a real-life case study in Belgium. We study the patient arrival pattern of the emergency department in depth and consider different patient acuity classes by disaggregating the arrival pattern. We determine the personnel staffing requirements and the design of the shifts based on the patient arrival rates per acuity class such that the resource staffing cost and the weighted patient waiting time are minimised. In order to solve this multi-objective optimisation problem, we construct a Pareto set of optimal solutions via the -constraints method. For a particular staffing composition, the proposed model minimises the patient waiting time subject to upper bounds on the staffing size using the Sample Average Approximation Method. In our computational experiments, we discern the impact of prioritising the emergency department arrivals. Triaging results in lower patient waiting times for higher priority acuity classes and to a higher waiting time for the lowest priority class, which does not require immediate care. Moreover, we perform a sensitivity analysis to verify the impact of the arrival and service pattern characteristics, the prioritisation weights between different acuity classes and the incorporated shift flexibility in the model.
WAITING TIMES OF QUASI-HOMOLOGOUS CORONAL MASS EJECTIONS FROM SUPER ACTIVE REGIONS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang Yuming; Liu Lijuan; Shen Chenglong
Why and how do some active regions (ARs) frequently produce coronal mass ejections (CMEs)? These are key questions for deepening our understanding of the mechanisms and processes of energy accumulation and sudden release in ARs and for improving our space weather prediction capability. Although some case studies have been performed, these questions are still far from fully answered. These issues are now being addressed statistically through an investigation of the waiting times of quasi-homologous CMEs from super ARs in solar cycle 23. It is found that the waiting times of quasi-homologous CMEs have a two-component distribution with a separation atmore » about 18 hr. The first component is a Gaussian-like distribution with a peak at about 7 hr, which indicates a tight physical connection between these quasi-homologous CMEs. The likelihood of two or more occurrences of CMEs faster than 1200 km s{sup -1} from the same AR within 18 hr is about 20%. Furthermore, the correlation analysis among CME waiting times, CME speeds, and CME occurrence rates reveals that these quantities are independent of each other, suggesting that the perturbation by preceding CMEs rather than free energy input is the direct cause of quasi-homologous CMEs. The peak waiting time of 7 hr probably characterizes the timescale of the growth of the instabilities triggered by preceding CMEs. This study uncovers some clues from a statistical perspective for us to understand quasi-homologous CMEs as well as CME-rich ARs.« less
McKenzie, Karen; Forsyth, Kirsty; O'Hare, Anne; McClure, Iain; Rutherford, Marion; Murray, Aja; Irvine, Linda
2016-05-01
The aim of this study was to explore the extent to which the Scottish Intercollegiate Guidelines Network 98 guidelines on the assessment and diagnosis of autism spectrum disorder were adhered to in child autism spectrum disorder diagnostic services in Scotland and whether there was a significant relationship between routine practice which more closely reflected these recommendations (increased adherence) and increased waiting times. Retrospective, cross-sectional case note analysis was applied to data from 80 case notes. Adherence ranged from a possible 0 (no adherence) to 19 (full adherence). Overall, 17/22 of the recommendations were adhered to in over 50 of the 80 cases and in 70 or more cases for 11/22 of the recommendations, with a mean adherence score of 16 (standard deviation = 1.9). No significant correlation was found between adherence and total wait time for untransformed (r = 0.15, p = 0.32) or transformed data (r = 0.12, p = 0.20). The results indicated that the assessment and diagnostic practices were consistent with the relevant Scottish Intercollegiate Guidelines Network 98 guideline recommendations. Increased adherence to the 19 included recommendations was not significantly related to increased total waiting times, indicating that the Scottish Intercollegiate Guidelines Network 98 recommendations have generally been integrated into practice, without a resultant increase in patient waits. © The Author(s) 2015.
Redesigning emergency department patient flows: application of Lean Thinking to health care.
King, Diane L; Ben-Tovim, David I; Bassham, Jane
2006-08-01
To describe in some detail the methods used and outcome of an application of concepts from Lean Thinking in establishing streams for patient flows in a teaching general hospital ED. Detailed understanding was gained through process mapping with staff followed by the identification of value streams (those patients likely to be discharged from the ED, those who were likely to be admitted) and the implementation of a process of seeing those patients that minimized complex queuing in the ED. Streaming had a significant impact on waiting times and total durations of stay in the ED. There was a general flattening of the waiting time across all groups. A slight increase in wait for Triage categories 2 and 3 patients was offset by reductions in wait for Triage category 4 patients. All groups of patients spent significantly less overall time in the department and the average number of patients in the ED at any time decreased. There was a significant reduction in number of patients who do not wait and a slight decrease in access block. The streaming of patients into groups of patients cared for by a specific team of doctors and nurses, and the minimizing of complex queues in this ED by altering the practices in relation to the function of the Australasian Triage Scale improved patient flow, thereby decreasing potential for overcrowding.
Harding, K E; Bottrell, J
2016-12-01
Waiting lists with triage systems are commonly used in outpatient physiotherapy but may not be effective. Could an alternative model of access and triage reduce waiting times over a sustained period with no additional resources? Observational study comparing retrospective data for 11 months prior to the introduction of a new model of access compared with data for the equivalent 11 months afterwards. Patients referred to a physiotherapy outpatient department at an outer metropolitan hospital before (n=721) and after (n=707) the introduction of the new model. A model of access and triage known as 'specific timely appointments for triage' (STAT), in which appointment slots are preserved in advance specifically for new patients based on calculation of average demand. Time from referral to first assessment, number of appointments per patient, occasions of non-attendance and total length of stay in the service. Median time from referral to first appointment was 18 days [interquartile range (IQR) 11 to 33 days] in the pre-intervention group, compared with 14 days (IQR 9 to 21 days) in the post-intervention group (P<0.01). The number of physiotherapy appointments also reduced (IQR 2 to 6 vs IQR 1 to 4; P<0.01). There were no changes in non-attendance rates or total time in the service. Waiting time for outpatient physiotherapy was 22% lower in the year following the introduction of the STAT model. While acknowledging the limitations of a pre- and post-measurement design, this model may have potential for reducing waiting times for outpatient physiotherapy without additional resources. Copyright © 2015 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.
Pomey, Marie-Pascale; Clavel, Nathalie; Amar, Claudia; Sabogale-Olarte, Juan Carlos; Sanmartin, Claudia; De Coster, Carolyn; Noseworthy, Tom
2017-09-07
In Canada, long waiting times for core specialized services have consistently been identified as a key barrier to access. Governments and organizations have responded with strategies for better access management, notably for total joint replacement (TJR) of the hip and knee. While wait time management strategies (WTMS) are promising, the factors which influence their sustainable implementation at the organizational level are understudied. Consequently, this study examined organizational and systemic factors that made it possible to sustain waiting times for TJR within federally established limits and for at least 18 months or more. The research design is a multiple case study of WTMS implementation. Five cases were selected across five Canadian provinces. Three success levels were pre-defined: 1) the WTMS maintained compliance with requirements for more than 18 months; 2) the WTMS met requirements for 18 months but could not sustain the level thereafter; 3) the WTMS never met requirements. For each case, we collected documents and interviewed key informants. We analyzed systemic and organizational factors, with particular attention to governance and leadership, culture, resources, methods, and tools. We found that successful organizations had specific characteristics: 1) management of the whole care continuum, 2) strong clinical leadership; 3) dedicated committees to coordinate and sustain strategy; 4) a culture based on trust and innovation. All strategies led to relatively similar unintended consequences. The main negative consequence was an initial increase in waiting times for TJR and the main positive consequence was operational enhancement of other areas of specialization based on the TJR model. This study highlights important differences in factors which help to achieve and sustain waiting times. To be sustainable, a WTMS needs to generate greater synergies between contextual-level strategy (provincial or regional) and organizational objectives and constraints. Managers at the organizational level should be vigilant with regard to unintended consequences that a WTMS in one area can have for other areas of care. A more systemic approach to sustainability can help avoid or mitigate undesirable unintended consequences.
Abdelqader, Abdelhai; Kabacam, Gokhan; Woreta, Tinsay A; Hamilton, James P; Luu, Harry; Al Khalloufi, Kawtar; Saberi, Behnam; Philosophe, Benjamin; Cameron, Andrew M; Gurakar, Ahmet
2017-02-01
Our goal was to investigate wait times related to hepatitis C virus treatment with direct acting antivirals before versus after liver transplant at a single center as well as wait times for insurance approval for preemptive treatment with these agents after liver transplant. We retrospectively evaluated hepatitis C virus infections in transplant recipients of deceased liver donations in 2014 and 2015. Demographics, hepatocellular carcinoma incidence, Model for End-Stage Liver Disease scores, and transplant wait times were compared between patients treated before or after liver transplant. Wait times to approval of direct-acting antiviral treatment were evaluated in those untreated before transplant. During our study period, of 67 deceased-donor liver transplants, 21 patients received hepatitis C virus treatment pretransplant (treated group) and 46 patients were not treated pretransplant (untreated group). Twenty-five patients in the untreated group received hepatitis C virus-positive donations, with all in this group treated with direct-acting antivirals. We found no statistically significant differences regarding age, sex, race, donation after cardiac death, or incidence of hepatocellular carcinoma between groups. The treated group had a longer median wait time (287 vs 172 days; P = .02). Twelve of the 46 untreated patients (26.1%) developed biopsy-proven hepatitis C virus-related relapse (median 87 days; range, 55-383 days). Preemptive direct-acting antiviral therapy was initiated at a median of 81 days in the untreated group. Although treatment of hepatitis C virus before liver transplant is an attractive option to eliminate the risk of complications, it can limit the donor pool for recipients to uninfected donors, significantly increasing wait times in regions with large hepatitis C virus-positive donor pools. Allocation of Model for End-Stage Liver Disease score was not different between the treated and untreated groups. Insurance companies should revise their policies for rapid approval of preemptive direct-acting antiviral treatment after liver transplant.
[Patients' satisfaction and waiting time in oncology day care centers in Champagne-Ardenne].
Debreuve-Theresette, A; Jovenin, N; Stona, A C; Kraïem-Leleu, M; Burde, F; Parent, D; Hettler, D; Rey, J B
2015-12-01
Quality of life of patients suffering from cancer may be influenced by the way healthcare is organized and by patient experiences. Nowadays, chemotherapy is often provided in day care centers. This study aimed to assess patient waiting time and satisfaction in oncology day care centers in Champagne-Ardenne, France. This cross-sectional survey involved all patients receiving ambulatory chemotherapy during a one-week period in day care centers of Champagne-Ardenne public and private healthcare institutions participating in the study. Sociodemographic, medical and outpatient data were collected. Patient satisfaction was measured using the Out-Patsat35 questionnaire. Eleven (out of 16) oncology day care centers and 441 patients participated in the study. Most of the patients were women (n=252, 57.1%) and the mean age was 61±12 years. The mean satisfaction score was 82±14 (out of 100) and the mean waiting time between the assigned appointment time and administration of chemotherapy was 97±60 min. This study has shown that waiting times are important. However, patients are satisfied with the healthcare organization, especially regarding nursing support. Early preparation of chemotherapy could improve these parameters. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Ju, John Chen; Gan, Soon Ann; Tan Siew Wee, Justine; Huang Yuchi, Peter; Mei Mei, Chan; Wong Mei Mei, Sharon; Fong, Kam Weng
2013-01-01
In major cancer centers, heavy patients load and multiple registration stations could cause significant wait time, and can be result in patient complains. Real-time patient journey data and visual display are useful tools in hospital patient queue management. This paper demonstrates how we capture patient queue data without deploying any tracing devices; and how to convert data into useful patient journey information to understand where interventions are likely to be most effective. During our system development, remarkable effort has been spent on resolving data discrepancy and balancing between accuracy and system performances. A web-based dashboard to display real-time information and a framework for data analysis were also developed to facilitate our clinics' operation. Result shows our system could eliminate more than 95% of data capturing errors and has improved patient wait time data accuracy since it was deployed.
Comparison of public and private bariatric surgery services in Canada.
Martin, Allan R; Klemensberg, Jason; Klein, Laz V; Urbach, David; Bell, Chaim M
2011-06-01
Surgical treatment of obesity is cost-effective and improves life expectancy. Roux-en-Y gastric bypass (RYGB) and adjustable gastric banding (AGB) are dominant surgical techniques, but RYGB is the only publicly insured procedure in all Canadian provinces. Private clinics currently offer AGB with minimal wait times. We sought to compare RYGB in public facilities with AGB in private clinics in terms of cost, wait times and certain aspects of patient care. We conducted telephone interviews of all bariatric surgery providers across Canada (100% response rate). We asked about various aspects of care, such as wait time, cost, pre- and postoperative care and surgeon experience. The median out-of-pocket cost for AGB at private facilities is $16,000 (range $13,160-$18,375). Private clinics have much shorter wait times for AGB than public facilities do for RYGB (1 v. 21 mo, p < 0.001). Private clinics provide significantly fewer preoperative visits with multidisciplinary health professionals (2.7 v. 4.3, p = 0.045), and 5 of 12 (42%) private clinics conduct AGB surgeries without on-site critical care for high-risk (based on the respondents' definitions) patients. Private clinics performing AGB offer short wait times, but the cost is high. We found a great deal of variation between pre- and postoperative care among bariatric surgery facilities, and in some cases patient care appears to be less comprehensive. Our findings suggest that further research on obesity treatment is needed to inform policy so that all Canadians can have equitable and timely access to proven, evidence-based care.
Ju, Feng; Lee, Hyo Kyung; Yu, Xinhua; Faris, Nicholas R; Rugless, Fedoria; Jiang, Shan; Li, Jingshan; Osarogiagbon, Raymond U
2017-12-01
The process of lung cancer care from initial lesion detection to treatment is complex, involving multiple steps, each introducing the potential for substantial delays. Identifying the steps with the greatest delays enables a focused effort to improve the timeliness of care-delivery, without sacrificing quality. We retrospectively reviewed clinical events from initial detection, through histologic diagnosis, radiologic and invasive staging, and medical clearance, to surgery for all patients who had an attempted resection of a suspected lung cancer in a community healthcare system. We used a computer process modeling approach to evaluate delays in care delivery, in order to identify potential 'bottlenecks' in waiting time, the reduction of which could produce greater care efficiency. We also conducted 'what-if' analyses to predict the relative impact of simulated changes in the care delivery process to determine the most efficient pathways to surgery. The waiting time between radiologic lesion detection and diagnostic biopsy, and the waiting time from radiologic staging to surgery were the two most critical bottlenecks impeding efficient care delivery (more than 3 times larger compared to reducing other waiting times). Additionally, instituting surgical consultation prior to cardiac consultation for medical clearance and decreasing the waiting time between CT scans and diagnostic biopsies, were potentially the most impactful measures to reduce care delays before surgery. Rigorous computer simulation modeling, using clinical data, can provide useful information to identify areas for improving the efficiency of care delivery by process engineering, for patients who receive surgery for lung cancer.
Spatial detection of tv channel logos as outliers from the content
NASA Astrophysics Data System (ADS)
Ekin, Ahmet; Braspenning, Ralph
2006-01-01
This paper proposes a purely image-based TV channel logo detection algorithm that can detect logos independently from their motion and transparency features. The proposed algorithm can robustly detect any type of logos, such as transparent and animated, without requiring any temporal constraints whereas known methods have to wait for the occurrence of large motion in the scene and assume stationary logos. The algorithm models logo pixels as outliers from the actual scene content that is represented by multiple 3-D histograms in the YC BC R space. We use four scene histograms corresponding to each of the four corners because the content characteristics change from one image corner to another. A further novelty of the proposed algorithm is that we define image corners and the areas where we compute the scene histograms by a cinematic technique called Golden Section Rule that is used by professionals. The robustness of the proposed algorithm is demonstrated over a dataset of representative TV content.
Nagao, Noriko; Tsuchiya, Aya; Ando, Sae; Arita, Mizue; Toyonaga, Takashi; Miyawaki, Ikuko
This study aimed to clarify psychosocial influences of waiting periods on patients undergoing endoscopic submucosal dissection for cancer at an advanced medical care facility in Japan. Subjects were consenting patients hospitalized from 2009 to 2010. Qualitative and quantitative data were gathered about patients' characteristics, disease and stage, and waiting period. Qualitative content analysis was used to analyze free statements and interview data. Subjects included 154 patients with an average wait period of 46.28 days for admission. Qualitative analysis revealed the following wait period perceptions. For calmness, results indicated (1) no anxiety, (2) relief based on doctors' positive judgment, (3) whatever happens/no choice, and (4) trust in doctor. For uneasiness, perceptions included (1) the sooner, the better/eagerly waiting, (2) anxiety and concern, and (3) emotional instability. Four waiting period coping types were identified: (1) making phone inquiries, (2) busy and forgot about the medical procedure, (3) relief from anxiety, and (4) unable to function well in daily life. Patients need to be educated about cancer progression and provided an estimated wait time. They also require more information about how to manage daily life such as monitoring factors from the nursing domain including physical condition, digestive symptoms, diet, and exercise.
Tsuchiya, Aya; Ando, Sae; Arita, Mizue; Toyonaga, Takashi; Miyawaki, Ikuko
2017-01-01
This study aimed to clarify psychosocial influences of waiting periods on patients undergoing endoscopic submucosal dissection for cancer at an advanced medical care facility in Japan. Subjects were consenting patients hospitalized from 2009 to 2010. Qualitative and quantitative data were gathered about patients' characteristics, disease and stage, and waiting period. Qualitative content analysis was used to analyze free statements and interview data. Subjects included 154 patients with an average wait period of 46.28 days for admission. Qualitative analysis revealed the following wait period perceptions. For calmness, results indicated (1) no anxiety, (2) relief based on doctors' positive judgment, (3) whatever happens/no choice, and (4) trust in doctor. For uneasiness, perceptions included (1) the sooner, the better/eagerly waiting, (2) anxiety and concern, and (3) emotional instability. Four waiting period coping types were identified: (1) making phone inquiries, (2) busy and forgot about the medical procedure, (3) relief from anxiety, and (4) unable to function well in daily life. Patients need to be educated about cancer progression and provided an estimated wait time. They also require more information about how to manage daily life such as monitoring factors from the nursing domain including physical condition, digestive symptoms, diet, and exercise. PMID:26987103
Factors affecting medication-order processing time.
Beaman, M A; Kotzan, J A
1982-11-01
The factors affecting medication-order processing time at one hospital were studied. The order processing time was determined by directly observing the time to process randomly selected new drug orders on all three work shifts during two one-week periods. An order could list more than one drug for an individual patient. The observer recorded the nature, location, and cost of the drugs ordered, as well as the time to process the order. The time and type of interruptions also were noted. The time to process a drug order was classified as six dependent variables: (1) total time, (2) work time, (3) check time, (4) waiting time I--time from arrival on the dumbwaiter until work was initiated, (5) waiting time II--time between completion of the work and initiation of checking, and (6) waiting time III--time after the check was completed until the order left on the dumbwaiter. The significant predictors of each of the six dependent variables were determined using stepwise multiple regression. The total time to process a prescription order was 58.33 +/- 48.72 minutes; the urgency status of the order was the only significant determinant of total time. Urgency status also significantly predicted the three waiting-time variables. Interruptions and the number of drugs on the order were significant determinants of work time and check time. Each telephone interruption increased the work time by 1.72 minutes. While the results of this study cannot be generalized to other institutions, pharmacy managers can use the method of determining factors that affect medication-order processing time to identify problem areas in their institutions.
Macleod, Anne Marie; Gollish, Jeffrey; Kennedy, Deborah; McGlasson, Rhona; Waddell, James
2009-01-01
The Joint Health and Disease Management Program in the Toronto Central Local Health Integration Network (TC LHIN) is envisioned as a comprehensive model of care for patients with hip and knee arthritis. It includes access to assessment services, education, self-management programs and other treatment programs, including specialist care as needed. As the first phase of this program, the hospitals in TC LHIN implemented a Hip and Knee Replacement Program to focus on improving access and quality of care, coordinating services and measuring wait times for patients waiting for hip or knee replacement surgery. The program involves healthcare providers, consumers and constituent hospitals within TC LHIN. The approach used for this program involved a definition of governance structure, broad stakeholder engagement to design program elements and plans for implementation and communication to ensure sustainability. The program and approach were designed to provide a model that is transferrable in its elements or its entirety to other patient populations and programs. Success has been achieved in creating a single wait list, developing technology to support referral management and wait time reporting, contributing to significant reductions in waits for timely assessment and treatment, building human resource capacity and improving patient and referring physician satisfaction with coordination of care.
A Streamlined Western Blot Exercise: An Efficient and Greener Approach in the Laboratory Classroom
ERIC Educational Resources Information Center
Ness, Traci L.; Robinson, Rebekah L.; Mojadedi, Wais; Peavy, Lydia; Weiland, Mitch H.
2015-01-01
SDS-PAGE and western blotting are two commonly taught protein detection techniques in biochemistry and molecular biology laboratory classrooms. A pitfall associated with incorporating these techniques into the laboratory is the significant wait times that do not allow students to obtain timely results. The waiting associated with SDS-PAGE comes…
ERIC Educational Resources Information Center
Rutherford, Marion; Burns, Morag; Gray, Duncan; Bremner, Lynne; Clegg, Sarah; Russell, Lucy; Smith, Charlie; O'Hare, Anne
2018-01-01
The 'autism diagnosis crisis' and long waiting times for assessment are as yet unresolved, leading to undue stress and limiting access to effective support. There is therefore a significant need for evidence to support practitioners in the development of efficient services, delivering acceptable waiting times and effectively meeting guideline…
A modelling framework for mitigating customers' waiting time at a vehicle inspection centre
NASA Astrophysics Data System (ADS)
Ahmad, Norazura; Abidin, Norhaslinda Zainal; Ilyas, Khibtiyah; Abduljabbar, Waleed Khalid
2017-11-01
In Malaysia, an agency that is entrusted by the Government to perform mandatory vehicle inspection for public, commercial and private vehicles, receive many customers daily. Often complaints of problems received from the customers are associated with waiting time that leads to lost of business and dissatisfied customers. To address this issue, we propose a framework for modelling a vehicle inspection system using an integration of simulation and optimization approaches. The strengths of simulation and optimization are reviewed briefly that is hoped to reveal the synergy between the established methods in determining an appropriate customer's waiting time for inspection at a vehicle inspection centre. Relevant concepts and preliminary results are also presented and discussed in this paper.
The effects of a lean transition on process times, patients and employees.
Simons, Pascale; Backes, Huub; Bergs, Jochen; Emans, Davy; Johannesma, Madelon; Jacobs, Maria; Marneffe, Wim; Vandijck, Dominique
2017-03-13
Purpose Treatment delays must be avoided, especially in oncology, to assure sustainable high-quality health care and increase the odds of survival. The purpose of this paper is to hypothesize that waiting times would decrease and patients and employees would benefit, when specific lean interventions are incorporated in an organizational improvement approach. Design/methodology/approach In 2013, 15 lean interventions were initiated to improve flow in a single radiotherapy institute. Process/waiting times, patient satisfaction, safety, employee satisfaction, and absenteeism were evaluated using a mixed methods methodology (2010-2014). Data from databases, surveys, and interviews were analyzed by time series analysis, χ 2 , multi-level regression, and t-tests. Findings Median waiting/process times improved from 20.2 days in 2012 to 16.3 days in 2014 ( p<0.001). The percentage of palliative patients for which waiting times had exceeded Dutch national norms (ten days) improved from 35 (six months in 2012: pre-intervention) to 16 percent (six months in 2013-2014: post-intervention; p<0.01), and the percentage exceeding national objectives (seven days) from 22 to 17 percent ( p=0.44). For curative patients, exceeding of norms (28 days) improved from 17 (2012) to 8 percent (2013-2014: p=0.05), and for the objectives (21 days) from 18 to 10 percent ( p<0.01). Reported safety incidents decreased 47 percent from 2009 to 2014, whereas safety culture, awareness, and intention to solve problems improved. Employee satisfaction improved slightly, and absenteeism decreased from 4.6 (2010) to 2.7 percent (2014; p<0.001). Originality/value Combining specific lean interventions with an organizational improvement approach improved waiting times, patient safety, employee satisfaction, and absenteeism on the short term. Continuing evaluation of effects should study the improvements sustainability.
Anthony, Samantha J; Annunziato, Rachel A; Fairey, Elise; Kelly, Vicky L; So, Stephanie; Wray, Jo
2014-08-01
The waiting period for an organ transplant has been described as a time of tremendous uncertainty and vulnerability, posing unique challenges and stressors for pediatric transplant candidates and their families. It has been identified as the most stressful stage of the transplant journey, yet little attention has been given to the physical, psychological, or social impact of the waiting period in the literature. In this review, we discuss the physical, nutritional, and psychosocial implications of the waiting period for child and adolescent transplant candidates and the impact on their parents and siblings. We identify areas for future research and provide recommendations for clinical practice to support children, adolescents, and families during the waiting period. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Improving Aircraft Refueling Procedures at Naval Air Station Oceana
2012-06-01
Station (NAS) Oceana, VA, using aircraft waiting time for fuel as a measure of performance. We develop a computer-assisted discrete-event simulation to...Station (NAS) Oceana, VA, using aircraft waiting time for fuel as a measure of performance. We develop a computer-assisted discrete-event simulation...server queue, with general interarrival and service time distributions gpm Gallons per minute JDK Java development kit M/M/1 Single-server queue
Self-organized criticality in type I X-ray bursts
NASA Astrophysics Data System (ADS)
Wang, J. S.; Wang, F. Y.; Dai, Z. G.
2017-11-01
Type I X-ray bursts in a low-mass X-ray binary are caused by unstable nuclear burning of accreted materials. Semi-analytical and numerical studies of unstable nuclear burning have successfully reproduced the partial properties of this kind of burst. However, some other properties (e.g. the waiting time) are not well explained. In this paper, we find that the probability distributions of fluence, peak count, rise time, duration and waiting time can be described as power-law-like distributions. This indicates that type I X-ray bursts may be governed by a self-organized criticality (SOC) process. The power-law index of the waiting time distribution (WTD) is around -1, which is not predicted by any current waiting time model. We propose a physical burst rate model, in which the mean occurrence rate is inversely proportional to time: λ ∝ t-1. In this case, the WTD is explained well by a non-stationary Poisson process within the SOC theory. In this theory, the burst size is also predicted to follow a power-law distribution, which requires that the emission area covers only part of the neutron star surface. Furthermore, we find that the WTDs of some astrophysical phenomena can also be described by similar occurrence rate models.
Simulated interactions of pedestrian crossings and motorized vehicles in residential areas
NASA Astrophysics Data System (ADS)
Wang, Yan; Peng, Zhongyi; Chen, Qun
2018-01-01
To evaluate whether motorized vehicles can travel through a residential area, this paper develops a cellular automata (CA) model to simulate the interactions between pedestrian crossings and motorized vehicles in a residential area. In this paper, pedestrians determine their crossing speed according to their judgments of the position and velocity of the upcoming vehicles. The pedestrians may walk slowly or quickly or even run, and the pedestrian crossing time influences the vehicle movement. In addition, the proposed model considers the safety margin time needed for pedestrians to cross, and pedestrian-vehicle conflict is considered using the vehicle collision avoidance rule. Through simulations of interactions of pedestrian crossings with motorized vehicles' movement on a typical road in a residential area, the average wait time for pedestrians to cross and the average vehicle velocity under different pedestrian crossing volumes, different vehicle flows and different maximum vehicle velocities are obtained. To avoid an excessive waiting time for pedestrians to cross, the vehicle flow should be less than 180 veh/h, which allows an average of less than 10 s of waiting time; if the vehicle flow rate is less than 36 veh/h, then the waiting time is approximately 1 s. Field observations are conducted to validate the simulation results.
Strategic attention deployment for delay of gratification in working and waiting situations.
Peake, Philip K; Mischel, Walter; Hebl, Michelle
2002-03-01
Two studies examined whether the detrimental effects of attention to rewards on delay of gratification in waiting situations holds-or reverses-in working situations. In Study 1, preschoolers waited or worked for desired delayed rewards. Delay times increased when children worked in the presence of rewards but, as predicted, this increase was due to the distraction provided by the work itself. not because attention to rewards motivated children to sustain work. Analysis of spontaneous attention deployment showed that attending to rewards reduces delay time regardless of the working or waiting nature of the task. Fixing attention on rewards was a particularly detrimental strategy regardless of the type of task. Study 2 showed that when the work is not engaging, however, attention to rewards can motivate instrumental work and facilitate delay of gratification as long as attention deployment does not become fixed on the rewards.
Simulation and Analysis of EXPRESS Run Frequency
2013-12-01
indicator, Customer Wait Time ( CWT ), is a measure of total wait time for a customer from the time they submit a need until it is fulfilled...Department of Defense 2000). MICAP hours is a special subset of CWT reserved for requirements that represent a mission capability need (i.e. an aircraft is...performance is tracked by total CWT and MICAP days, which are convertible to hours by multiplying by 24. CWT is tracked by measuring the total time
TRMM Version 7 Near-Realtime Data Products
NASA Technical Reports Server (NTRS)
Tocker, Erich Franz; Kelley, Owen
2012-01-01
The TRMM data system has been providing near-realtime data products to the community since late 1999. While the TRMM project never had near-realtime production requirements, the science and applications communities had a great interest in receiving TRMM data as quickly as possible. As a result these NRT data are provided under a best-effort scenario but with the objective of having the swath data products available within three hours of data collection 90% of the time. In July of 2011 the Joint Precipitation Measurement Missions Science Team (JPST) authorized the reprocessing of TRMM mission data using the new version 7 algorithms. The reprocessing of the 14+ years of the mission was concluded within 30 days. Version 7 algorithms had substantial changes in the data product file formats both for data and metadata. In addition, the algorithms themselves had major modifications and improvements. The general approach to versioning up the NRT is to wait for the regular production algorithms to have run for a while and shake out any issues that might arise from the new version before updating the NRT products. Because of the substantial changes in data/metadata formats as well as the algorithm improvements themselves, the update of NRT to V7 followed an even more conservative path than usual. This was done to ensure that applications agencies and other users of the TRMM NRT would not be faces with short-timeframes for conversion to the new format. This paper will describe the process by which the TRMM NRT was updated to V7 and the V7 data products themselves.
Improving the quality of palliative care for ambulatory patients with lung cancer
von Plessen, Christian; Aslaksen, Aslak
2005-01-01
Problem Most patients with advanced lung cancer currently receive much of their health care, including chemotherapy, as outpatients. Patients have to deal with the complex and time consuming logistics of ambulatory cancer care. At the same time, members of staff often waste considerable time and energy in organisational aspects of care that could be better used in direct interaction with patients. Design Quality improvement study using direct observation and run and flow charts, and focus group meetings with patients and families regarding perceptions of the clinic and with staff regarding satisfaction with working conditions. Setting Thoracic oncology outpatient clinic at a Norwegian university hospital where patients receive chemotherapy and complementary palliative care. Key measures for improvement Waiting time and time wasted during consultations; calmer working situation at the clinic; satisfaction among patients. Strategies for change Rescheduled patients' appointments, automated retrieval of blood test results, systematic reporting in patients' files, design of an information leaflet, and refurnishing of the waiting area at the clinic. Effects of change Interventions resulted in increased satisfaction for patients and staff, reduced waiting time, and reduced variability of waiting time. Lessons learnt Direct observation, focus groups, questionnaires on patients' satisfaction, and measurement of process time were useful in systematically improving care in this outpatient clinic. The description of this experience can serve as an example for the improvement of a microsystem, particularly in other settings with similar problems. PMID:15933354
Mary Budd Rowe: a storyteller of science
NASA Astrophysics Data System (ADS)
Bianchini, Julie A.
2008-12-01
This article examines Mary Budd Rowe's groundbreaking and far-reaching contributions to science education. Rowe is best known for her research on wait-time: the idea that teachers can improve the quality and length of classroom discussions by waiting at least 3 s before and after student responses. Her wait-time research grew from and helped inform her staunch advocacy of science education as inquiry; Rowe saw wonder and excitement as central to the teaching and learning of science. She spent much of her professional life designing professional development experiences and innovative curriculum materials to help teachers, particularly elementary school teachers, enact inquiry in their classrooms.
NASA Astrophysics Data System (ADS)
Motaghedi-Larijani, Arash; Aminnayeri, Majid
2017-03-01
Cross-docking is a supply-chain strategy that can reduce transportation and inventory costs. This study is motivated by a fruit and vegetable distribution centre in Tehran, which has cross-docks and a limited time to admit outbound trucks. In this article, outbound trucks are assumed to arrive at the cross-dock with a single outbound door with a uniform distribution (0,L). The total number of assigned trucks is constant and the loading time is fixed. A queuing model is modified for this situation and the expected waiting time of each customer is calculated. Then, a curve for the waiting time is calculated. Finally, the length of window time L is optimized to minimize the total cost, which includes the waiting time of the trucks and the admission cost of the cross-dock. Some illustrative examples of cross-docking are presented and solved using the proposed method.
Fast Adapting Ensemble: A New Algorithm for Mining Data Streams with Concept Drift
Ortíz Díaz, Agustín; Ramos-Jiménez, Gonzalo; Frías Blanco, Isvani; Caballero Mota, Yailé; Morales-Bueno, Rafael
2015-01-01
The treatment of large data streams in the presence of concept drifts is one of the main challenges in the field of data mining, particularly when the algorithms have to deal with concepts that disappear and then reappear. This paper presents a new algorithm, called Fast Adapting Ensemble (FAE), which adapts very quickly to both abrupt and gradual concept drifts, and has been specifically designed to deal with recurring concepts. FAE processes the learning examples in blocks of the same size, but it does not have to wait for the batch to be complete in order to adapt its base classification mechanism. FAE incorporates a drift detector to improve the handling of abrupt concept drifts and stores a set of inactive classifiers that represent old concepts, which are activated very quickly when these concepts reappear. We compare our new algorithm with various well-known learning algorithms, taking into account, common benchmark datasets. The experiments show promising results from the proposed algorithm (regarding accuracy and runtime), handling different types of concept drifts. PMID:25879051
Modeling of waiting times and price changes in currency exchange data
NASA Astrophysics Data System (ADS)
Repetowicz, Przemysław; Richmond, Peter
2004-11-01
A theory which describes the share price evolution at financial markets as a continuous-time random walk (Physica A 287 (2000) 468, Physica A 314 (2002) 749, Eur. Phys. J. B 27 (2002) 273, Physica A 376 (2000) 284) has been generalized in order to take into account the dependence of waiting times t on price returns x. A joint probability density function (pdf) φ(x,t) which uses the concept of a Lévy stable distribution is worked out. The theory is fitted to high-frequency US $/Japanese Yen exchange rate and low-frequency 19th century Irish stock data. The theory has been fitted both to price return and to waiting time data and the adherence to data, in terms of the χ2 test statistic, has been improved when compared to the old theory.
Morton, Alec; Bevan, Gwyn
2008-02-01
The current paper reviews and contrasts a management science view of waiting for healthcare, which centres on queues as devices for buffering demand, with an economic view, which stresses the role of the incentive structure, in the context of English Accident and Emergency Departments. We demonstrate that the management science view provides insight into waiting time performance within a single facility but is limited in its ability to shed light on variations in performance across facilities. We argue, with reference to supporting data, that such variations may be explainable by a proper understanding of the incentive structure in A&E Departments.
Quality-of-Life Assessment of Fibroid Treatment Options and Outcomes
Kong, Chung Yin; Tempany, Clare M.; Swan, J. Shannon
2011-01-01
Purpose: To obtain utilities (a unit of measure of a person’s relative preferences for different health states compared with death or worst possible outcome) for uterine fibroids before and after treatment and to measure short-term utilities for the following uterine fibroid treatments: abdominal hysterectomy, magnetic resonance (MR) imaging–guided focused ultrasound surgery, and uterine artery embolization (UAE). Materials and Methods: This retrospective study was approved by the institutional review board and was HIPAA compliant. The waiting trade-off (WTO) method, a variation on the time trade-off (TTO) method, is used to obtain utilities for diagnostic procedures on the basis of the fact that people wait longer to avoid noxious tests and/or procedures. The WTO method provides short-term quality of life tolls in terms of quality-adjusted life-weeks by scaling wait times with pre- and posttreatment utilities. Utilities for uterine fibroids before and after treatment were obtained with the TTO method and a visual analog scale (VAS) by using a questionnaire administered by means of a phone interview. WTO wait times were adjusted for quality of life with VAS and TTO utilities and a transformation of VAS. Wait times were compared by using nonparametric tests. The study participants included 62 patients who had undergone abdominal hysterectomy, 74 who had undergone UAE, and 61 who had undergone MR imaging–guided focused ultrasound surgery. Results: Quality of life increased with all treatments. The median WTO wait time was higher for hysterectomy (21.6 weeks) than for UAE or MR imaging–guided focused ultrasound surgery (14.1 weeks for both) (P < .05). Quality-adjusted life-week tolls were smaller when scaled according to TTO than when scaled according to VAS or transformation of VAS. Conclusion: Quality of life increased after all fibroid treatments. WTO is feasible for assessing the quality-adjusted morbidity of treatment procedures. © RSNA, 2011 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11100704/-/DC1 PMID:21364084
Armstrong, David; Barkun, Alan NG; Chen, Ying; Daniels, Sandra; Hollingworth, Roger; Hunt, Richard H; Leddin, Desmond
2008-01-01
BACKGROUND: Canadian wait time data are available for the treatment of cancer and heart disease, as well as for joint replacement, cataract surgery and diagnostic imaging procedures. Wait times for gastroenterology consultation and procedures have not been studied, although digestive diseases pose a greater economic burden in Canada than cancer or heart disease. METHODS: Specialist physicians completed the practice audit if they provided digestive health care, accepted new patients and recorded referral dates. For patients seen for consultation or investigation over a one-week period, preprogrammed personal digital assistants were used to collect data including the main reason for referral, initial referral and consultation dates, procedure dates (if performed), personal and family history, and patient symptoms, signs and test results. Patient triaging, appropriateness of the referral and timeliness of care were noted. RESULTS: Over 10 months, 199 physicians recorded details of 5559 referrals, including 1903 visits for procedures. The distribution of total wait times (from referral to procedure) nationally was highly skewed at 91/203 days (median/75th percentile), with substantial interprovincial variation: British Columbia, 66/185 days; Alberta, 134/284 days; Ontario, 110/208 days; Quebec, 71/149 days; New Brunswick, 104/234 days; and Nova Scotia, 42/84 days. The percentage of physicians by province offering average-risk screening colonoscopy varied from 29% to 100%. DISCUSSION: Access to specialist gastroenterology care in Canada is limited by long wait times, which exceed clinically reasonable waits for specialist treatment. Although exhibiting some methodological limitations, this large practice audit sampling offers broadly generalized results, as well as a means to identify barriers to health care delivery and evaluate strategies to address these barriers, with the goals of expediting appropriate care for patients with digestive health disorders and ameliorating the personal and societal burdens imposed by digestive diseases. PMID:18299734
Piccininni, Caroline; Bisnaire, Lise; Penner, Melanie
2017-01-01
Earlier access to intensive behavioral intervention (IBI) is associated with improved outcomes for children with severe autism spectrum disorder (ASD); however, there are long waiting times for this program. No analyses have been performed modeling the cost-effectiveness of wait time reduction for IBI. To model the starting age for IBI with reduced wait time (RWT) (by half) and eliminated wait time (EWT), and perform a cost-effectiveness analysis comparing RWT and EWT with current wait time (CWT) from government and societal perspectives. Published waiting times were used to model the mean starting age for IBI for CWT, RWT, and EWT in children diagnosed with severe ASD who were treated at Ontario's Autism Intervention Program. Inputs were loaded into a decision analytic model, with an annual discount rate of 3% applied. Incremental cost-effectiveness ratios (ICERs) were determined. One-way and probabilistic sensitivity analyses were performed to assess the effect of model uncertainty. We used data from the year 2012 (January 1 through December 31) provided from the Children's Hospital of Eastern Ontario IBI center for the starting ages. Data analysis was done from May through July 2015. The outcome was independence measured in dependency-free life-years (DFLYs) to 65 years of age. To derive this, expected IQ was modeled based on probability of early (age <4 years) or late (age ≥4 years) access to IBI. Probabilities of having an IQ in the normal (≥70) or intellectual disability (<70) range were calculated. The IQ strata were assigned probabilities of achieving an independent (60 DFLYs), semidependent (30 DFLYs), or dependent (0 DFLYs) outcome. Costs were calculated for provincial government and societal perspectives in Canadian dollars (Can$1 = US$0.78). The mean starting ages for IBI were 5.24 years for CWT, 3.89 years for RWT, and 2.71 years for EWT. From the provincial government perspective, EWT was the dominant strategy, generating the most DFLYs for Can$53 000 less per individual to 65 years of age than CWT. From the societal perspective, EWT produced lifetime savings of Can$267 000 per individual compared with CWT. The ICERs were most sensitive to uncertainty in the starting age for IBI and in achieving a normal IQ based on starting age. This study predicts the long-term effect of the current disparity between IBI service needs and the amount of IBI being delivered in the province of Ontario. The results suggest that providing timely access optimizes IBI outcomes, improves future independence, and lessens costs from provincial and societal perspectives.
Analysis of Trajectory Parameters for Probe and Round-Trip Missions to Venus
NASA Technical Reports Server (NTRS)
Dugan, James F., Jr.; Simsic, Carl R.
1960-01-01
For one-way transfers between Earth and Venus, charts are obtained that show velocity, time, and angle parameters as functions of the eccentricity and semilatus rectum of the Sun-focused vehicle conic. From these curves, others are obtained that are useful in planning one-way and round-trip missions to Venus. The analysis is characterized by circular coplanar planetary orbits, successive two-body approximations, impulsive velocity changes, and circular parking orbits at 1.1 planet radii. For round trips the mission time considered ranges from 65 to 788 days, while wait time spent in the parking orbit at Venus ranges from 0 to 467 days. Individual velocity increments, one-way travel times, and departure dates are presented for round trips requiring the minimum total velocity increment. For both single-pass and orbiting Venusian probes, the time span available for launch becomes appreciable with only a small increase in velocity-increment capability above the minimum requirement. Velocity-increment increases are much more effective in reducing travel time for single-pass probes than they are for orbiting probes. Round trips composed of a direct route along an ellipse tangent to Earth's orbit and an aphelion route result in the minimum total velocity increment for wait times less than 100 days and mission times ranging from 145 to 612 days. Minimum-total-velocity-increment trips may be taken along perihelion-perihelion routes for wait times ranging from 300 to 467 days. These wait times occur during missions lasting from 640 to 759 days.
ERIC Educational Resources Information Center
Ingram, Jenni; Elliott, Victoria
2016-01-01
Extending the pauses between teachers' and students' turns (wait time) has been recommended as a way of improving classroom learning. Drawing on the Conversation Analysis literature on classroom interactions alongside extracts of classroom interactions, the relationship between these pauses and the interactional behaviour of teachers and students…
Factors Associated with Waiting Time for Breast Cancer Treatment in a Teaching Hospital in Ghana
ERIC Educational Resources Information Center
Dedey, Florence; Wu, Lily; Ayettey, Hannah; Sanuade, Olutobi A.; Akingbola, Titilola S.; Hewlett, Sandra A.; Tayo, Bamidele O.; Cole, Helen V.; de-Graft Aikins, Ama; Ogedegbe, Gbenga; Adanu, Richard
2016-01-01
Background: Breast cancer is the leading cause of cancer-related mortality among women in Ghana. Data are limited on the predictors of poor outcomes in breast cancer patients in low-income countries; however, prolonged waiting time has been implicated. Among breast cancer patients who received treatment at Korle Bu Teaching Hospital, this study…
Perception of randomness: On the time of streaks.
Sun, Yanlong; Wang, Hongbin
2010-12-01
People tend to think that streaks in random sequential events are rare and remarkable. When they actually encounter streaks, they tend to consider the underlying process as non-random. The present paper examines the time of pattern occurrences in sequences of Bernoulli trials, and shows that among all patterns of the same length, a streak is the most delayed pattern for its first occurrence. It is argued that when time is of essence, how often a pattern is to occur (mean time, or, frequency) and when a pattern is to first occur (waiting time) are different questions and bear different psychological relevance. The waiting time statistics may provide a quantitative measure to the psychological distance when people are expecting a probabilistic event, and such measure is consistent with both of the representativeness and availability heuristics in people's perception of randomness. We discuss some of the recent empirical findings and suggest that people's judgment and generation of random sequences may be guided by their actual experiences of the waiting time statistics. Published by Elsevier Inc.
Renner, Regina-Maria; Edelman, Alison B; Nichols, Mark D; Jensen, Jeffrey T; Lim, Jeong Y; Bednarek, Paula H
2016-11-01
Our objective was to evaluate two different aspects of the paracervical block (PCB) technique for first trimester surgical abortion, to compare a 3-min wait prior to cervical dilation to no wait and to compare four-site with two-site injection. We conducted two consecutive randomized, single-blinded noninferiority trials. In the first trial, women <11 weeks gestational age received a 20-mL 1% buffered lidocaine four-site PCB with either a 3-min wait between PCB injection and dilation or no wait. In the second trial, we compared a four-site with a two-site PCB. We evaluated dilation pain [100-mm visual analogue scale (VAS)] as the primary outcome. Secondary outcomes included pain at additional time points, anxiety, satisfaction and adverse events. Both trials fully enrolled (total n=332). Results were inconclusive as to whether no wait was noninferior to waiting 3-min prior to cervical dilation for dilation pain [VAS: 63 mm (SD, 24 mm) vs. 56 mm (SD, 32mm)] and as to whether a two-site PCB was noninferior to a four-site block [VAS: 68 mm (SD, 21 mm) vs. 60 mm (SD, 30 mm)]. Noninferiority analysis was inconclusive because the confidence interval of the mean pain score difference between groups included the predefined inferiority margin of 13-mm pain difference. Superiority analysis showed the four-site PCB to be superior to the two-site PCB. It remained inconclusive whether a 3-min wait time between PCB and cervical dilation provides noninferior pain control for first trimester surgical abortion. However, a four-site PCB appeared to be superior to a two-site PCB. It remained inconclusive whether a 3-min wait time between PCB and cervical dilation or using a two-site instead of a four-site PCB provided noninferior pain control for first trimester surgical abortion. This study did not assess whether the combination of the two separate factors provides additive benefit. Copyright © 2016 Elsevier Inc. All rights reserved.
Rutherford, Marion; Burns, Morag; Gray, Duncan; Bremner, Lynne; Clegg, Sarah; Russell, Lucy; Smith, Charlie; O'Hare, Anne
2018-05-01
The 'autism diagnosis crisis' and long waiting times for assessment are as yet unresolved, leading to undue stress and limiting access to effective support. There is therefore a significant need for evidence to support practitioners in the development of efficient services, delivering acceptable waiting times and effectively meeting guideline standards. This study reports statistically significant reductions in waiting times for autism diagnostic assessment following a children's health service improvement programme. The average wait between referral and first appointment reduced from 14.2 to 10.4 weeks (t(21) = 4.3, p < 0.05) and between referral and diagnosis shared, reduced from 270 to 122.5 days, (t(20) = 5.5, p < 0.05). The proportion of girls identified increased from 5.6 to 2.7:1. Methods reported include: local improvement action planning; evidence based pathways; systematic clinical data gathering and a training plan. This is a highly significant finding for many health services wrestling with the challenges of demand and capacity for autism diagnosis and assessment.
Transformation of a Pediatric Primary Care Waiting Room: Creating a Bridge to Community Resources.
Henize, Adrienne W; Beck, Andrew F; Klein, Melissa D; Morehous, John; Kahn, Robert S
2018-06-01
Introduction Children and families living in poverty frequently encounter social risks that significantly affect their health and well-being. Physicians' near universal access to at-risk children and their parents presents opportunities to address social risks, but time constraints frequently interfere. We sought to redesign our waiting room to create a clinic-to-community bridge and evaluate the impact of that redesign on family-centered outcomes. Methods We conducted a pre-post study of a waiting room redesign at a large, academic pediatric primary care center. Design experts sought input about an optimal waiting room from families, community partners and medical providers. Family caregivers were surveyed before and after redesign regarding perceived availability of help with social needs and access to community resources, and hospitality and feelings of stress. Pre-post differences were assessed using the Chi square or Wilcoxon rank sum test. Results The key redesign concepts that emerged included linkages to community organizations, a welcoming environment, and positive distractions for children. A total of 313 caregiver surveys were completed (pre-160; post-153). Compared to pre-redesign, caregivers surveyed post-redesign were significantly more likely to perceive the waiting room as a place to obtain help connecting to community resources and find information about clinical and educational resources (both p < 0.05). Families were also significantly more likely to report the waiting room as more welcoming and relaxing, with sufficient privacy and space (all p < 0.05). Discussion Waiting rooms, typically a place of wasted time and space, can be redesigned to enhance families' engagement and connection to community resources.
Qvist, Johan; Schober, Helmut; Halle, Bertil
2011-04-14
One of the outstanding challenges presented by liquid water is to understand how molecules can move on a picosecond time scale despite being incorporated in a three-dimensional network of relatively strong H-bonds. This challenge is exacerbated in the supercooled state, where the dramatic slowing down of structural dynamics is reminiscent of the, equally poorly understood, generic behavior of liquids near the glass transition temperature. By probing single-molecule dynamics on a wide range of time and length scales, quasielastic neutron scattering (QENS) can potentially reveal the mechanistic details of water's structural dynamics, but because of interpretational ambiguities this potential has not been fully realized. To resolve these issues, we present here an extensive set of high-quality QENS data from water in the range 253-293 K and a corresponding set of molecular dynamics (MD) simulations to facilitate and validate the interpretation. Using a model-free approach, we analyze the QENS data in terms of two motional components. Based on the dynamical clustering observed in MD trajectories, we identify these components with two distinct types of structural dynamics: picosecond local (L) structural fluctuations within dynamical basins and slower interbasin jumps (J). The Q-dependence of the dominant QENS component, associated with J dynamics, can be quantitatively rationalized with a continuous-time random walk (CTRW) model with an apparent jump length that depends on low-order moments of the jump length and waiting time distributions. Using a simple coarse-graining algorithm to quantitatively identify dynamical basins, we map the newtonian MD trajectory on a CTRW trajectory, from which the jump length and waiting time distributions are computed. The jump length distribution is gaussian and the rms jump length increases from 1.5 to 1.9 Å as the temperature increases from 253 to 293 K. The rms basin radius increases from 0.71 to 0.75 Å over the same range. The waiting time distribution is exponential at all investigated temperatures, ruling out significant dynamical heterogeneity. However, a simulation at 238 K reveals a small but significant dynamical heterogeneity. The macroscopic diffusion coefficient deduced from the QENS data agrees quantitatively with NMR and tracer results. We compare our QENS analysis with existing approaches, arguing that the apparent dynamical heterogeneity implied by stretched exponential fitting functions results from the failure to distinguish intrabasin (L) from interbasin (J) structural dynamics. We propose that the apparent dynamical singularity at ∼220 K corresponds to freezing out of J dynamics, while the calorimetric glass transition corresponds to freezing out of L dynamics.
NASA Astrophysics Data System (ADS)
Qvist, Johan; Schober, Helmut; Halle, Bertil
2011-04-01
One of the outstanding challenges presented by liquid water is to understand how molecules can move on a picosecond time scale despite being incorporated in a three-dimensional network of relatively strong H-bonds. This challenge is exacerbated in the supercooled state, where the dramatic slowing down of structural dynamics is reminiscent of the, equally poorly understood, generic behavior of liquids near the glass transition temperature. By probing single-molecule dynamics on a wide range of time and length scales, quasielastic neutron scattering (QENS) can potentially reveal the mechanistic details of water's structural dynamics, but because of interpretational ambiguities this potential has not been fully realized. To resolve these issues, we present here an extensive set of high-quality QENS data from water in the range 253-293 K and a corresponding set of molecular dynamics (MD) simulations to facilitate and validate the interpretation. Using a model-free approach, we analyze the QENS data in terms of two motional components. Based on the dynamical clustering observed in MD trajectories, we identify these components with two distinct types of structural dynamics: picosecond local (L) structural fluctuations within dynamical basins and slower interbasin jumps (J). The Q-dependence of the dominant QENS component, associated with J dynamics, can be quantitatively rationalized with a continuous-time random walk (CTRW) model with an apparent jump length that depends on low-order moments of the jump length and waiting time distributions. Using a simple coarse-graining algorithm to quantitatively identify dynamical basins, we map the Newtonian MD trajectory on a CTRW trajectory, from which the jump length and waiting time distributions are computed. The jump length distribution is Gaussian and the rms jump length increases from 1.5 to 1.9 Å as the temperature increases from 253 to 293 K. The rms basin radius increases from 0.71 to 0.75 Å over the same range. The waiting time distribution is exponential at all investigated temperatures, ruling out significant dynamical heterogeneity. However, a simulation at 238 K reveals a small but significant dynamical heterogeneity. The macroscopic diffusion coefficient deduced from the QENS data agrees quantitatively with NMR and tracer results. We compare our QENS analysis with existing approaches, arguing that the apparent dynamical heterogeneity implied by stretched exponential fitting functions results from the failure to distinguish intrabasin (L) from interbasin (J) structural dynamics. We propose that the apparent dynamical singularity at ˜220 K corresponds to freezing out of J dynamics, while the calorimetric glass transition corresponds to freezing out of L dynamics.
Built spaces and features associated with user satisfaction in maternity waiting homes in Malawi.
McIntosh, Nathalie; Gruits, Patricia; Oppel, Eva; Shao, Amie
2018-07-01
To assess satisfaction with maternity waiting home built spaces and features in women who are at risk for underutilizing maternity waiting homes (i.e. residential facilities that temporarily house near-term pregnant mothers close to healthcare facilities that provide obstetrical care). Specifically we wanted to answer the questions: (1) Are built spaces and features associated with maternity waiting home user satisfaction? (2) Can built spaces and features designed to improve hygiene, comfort, privacy and function improve maternity waiting home user satisfaction? And (3) Which built spaces and features are most important for maternity waiting home user satisfaction? A cross-sectional study comparing satisfaction with standard and non-standard maternity waiting home designs. Between December 2016 and February 2017 we surveyed expectant mothers at two maternity waiting homes that differed in their design of built spaces and features. We used bivariate analyses to assess if built spaces and features were associated with satisfaction. We compared ratings of built spaces and features between the two maternity waiting homes using chi-squares and t-tests to assess if design features to improve hygiene, comfort, privacy and function were associated with higher satisfaction. We used exploratory robust regression analysis to examine the relationship between built spaces and features and maternity waiting home satisfaction. Two maternity waiting homes in Malawi, one that incorporated non-standardized design features to improve hygiene, comfort, privacy, and function (Kasungu maternity waiting home) and the other that had a standard maternity waiting home design (Dowa maternity waiting home). 322 expectant mothers at risk for underutilizing maternity waiting homes (i.e. first-time mothers and those with no pregnancy risk factors) who had stayed at the Kasungu or Dowa maternity waiting homes. There were significant differences in ratings of built spaces and features between the two differently designed maternity waiting homes, with the non-standard design having higher ratings for: adequacy of toilets, and ratings of heating/cooling, air and water quality, sanitation, toilets/showers and kitchen facilities, building maintenance, sleep area, private storage space, comfort level, outdoor spaces and overall satisfaction (p = <.0001 for all). The final regression model showed that built spaces and features that are most important for maternity waiting home user satisfaction are toilets/showers, guardian spaces, safety, building maintenance, sleep area and private storage space (R 2 = 0.28). The design of maternity waiting home built spaces and features is associated with user satisfaction in women at risk for underutilizing maternity waiting homes, especially related to toilets/showers, guardian spaces, safety, building maintenance, sleep area and private storage space. Improving maternity waiting home built spaces and features may offer a promising area for improving maternity waiting home satisfaction and reducing barriers to maternity waiting home use. Copyright © 2018 Elsevier Ltd. All rights reserved.
Generalized priority-queue network dynamics: Impact of team and hierarchy
NASA Astrophysics Data System (ADS)
Cho, Won-Kuk; Min, Byungjoon; Goh, K.-I.; Kim, I.-M.
2010-06-01
We study the effect of team and hierarchy on the waiting-time dynamics of priority-queue networks. To this end, we introduce generalized priority-queue network models incorporating interaction rules based on team-execution and hierarchy in decision making, respectively. It is numerically found that the waiting-time distribution exhibits a power law for long waiting times in both cases, yet with different exponents depending on the team size and the position of queue nodes in the hierarchy, respectively. The observed power-law behaviors have in many cases a corresponding single or pairwise-interacting queue dynamics, suggesting that the pairwise interaction may constitute a major dynamic consequence in the priority-queue networks. It is also found that the reciprocity of influence is a relevant factor for the priority-queue network dynamics.
Improving Efficiency While Improving Patient Care in a Student-Run Free Clinic.
Lee, Jason S; Combs, Kristen; Pasarica, Magdalena
2017-01-01
Student-run free clinics (SRFCs) have the capacity to decrease health care inequity in underserved populations. These facilities can benefit from improved patient experience and outcomes. We implemented a series of quality improvement interventions with the objectives to decrease patient wait times and to increase the variety of services provided. A needs assessment was performed. Problems related to time management, communication between staff and providers, clinic resources, and methods for assessing clinic performance were identified as targets to reduce wait times and improve the variety of services provided. Seventeen interventions were designed and implemented over a 2-month period. The interventions resulted in improved efficiency for clinic operations and reduced patient wait times. The number of specialty providers, patient visits for specialty care, lifestyle education visits for disease prevention and treatment, free medications, and free laboratory investigations increased to achieve the goal of improving the availability and the variety of services provided. We demonstrated that it is feasible to implement successful quality improvement interventions in SRFCs to decrease patient wait times and to increase the variety of services provided. We believe that the changes we implemented can serve as a model for other SRFCs to improve their performance. © Copyright 2017 by the American Board of Family Medicine.
Ierardo, G; Luzzi, V; Vestri, A; Sfasciotti, G L; Polimeni, A
2008-03-01
Healthcare facility management requires the optimisation of the quality of services offered. The Authors adopted a questionnaire as a means to assess customer satisfaction and needs. The Questionnaire has been designed to address adults, i.e., parents or guardians of children attending the Paediatric unit as patients. To estimate their degree of satisfaction, either regarding the environment where children are treated or about the direct interactions between the parents and the structure (waiting room, waiting time, treatment time and time needed to make the payments, costs, etc.), the questionnaire was submitted to a sample of approximately 600 customers, between March and June of 2005. On one hand results provide a pleasant confirmation on customers' perception of the service, especially regarding the direct relationship between the parties; on the other, they highlight aspects that could be improved (waiting room, optimisation of waiting time), distinguishing between factors that need extra funding to be implemented, and those that, instead, could be simply improved through a better and more efficient organisation of labour and time. The present analysis and previous experiences confirm that appraisal of the degree of customers' satisfaction by means of questionnaires is a valid and necessary instrument for the quality improvement of a healthcare service. Doing so, economic and human resources can be more efficiently allocated.
Study of cache performance in distributed environment for data processing
NASA Astrophysics Data System (ADS)
Makatun, Dzmitry; Lauret, Jérôme; Šumbera, Michal
2014-06-01
Processing data in distributed environment has found its application in many fields of science (Nuclear and Particle Physics (NPP), astronomy, biology to name only those). Efficiently transferring data between sites is an essential part of such processing. The implementation of caching strategies in data transfer software and tools, such as the Reasoner for Intelligent File Transfer (RIFT) being developed in the STAR collaboration, can significantly decrease network load and waiting time by reusing the knowledge of data provenance as well as data placed in transfer cache to further expand on the availability of sources for files and data-sets. Though, a great variety of caching algorithms is known, a study is needed to evaluate which one can deliver the best performance in data access considering the realistic demand patterns. Records of access to the complete data-sets of NPP experiments were analyzed and used as input for computer simulations. Series of simulations were done in order to estimate the possible cache hits and cache hits per byte for known caching algorithms. The simulations were done for cache of different sizes within interval 0.001 - 90% of complete data-set and low-watermark within 0-90%. Records of data access were taken from several experiments and within different time intervals in order to validate the results. In this paper, we will discuss the different data caching strategies from canonical algorithms to hybrid cache strategies, present the results of our simulations for the diverse algorithms, debate and identify the choice for the best algorithm in the context of Physics Data analysis in NPP. While the results of those studies have been implemented in RIFT, they can also be used when setting up cache in any other computational work-flow (Cloud processing for example) or managing data storages with partial replicas of the entire data-set.
Beck, Alison; Burdett, Mark; Lewis, Helen
2015-06-01
To investigate the impact of waiting for psychological therapy on client well-being as measured by the Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) global distress (GD) score. Global distress scores were retrieved for all clients referred for psychological therapy in a secondary care mental health service between November 2006 and May 2013 and who had completed a CORE-OM at assessment and first session. GD scores for a subgroup of 103 clients who had completed a CORE-OM during the last therapy session were also reviewed. The study sample experienced a median wait of 41.14 weeks between assessment and first session. The relationship between wait time from referral acceptance to assessment, and assessment GD score was not significant. During the period between assessment and first session no significant difference in GD score was observed. Nevertheless 29.1% of the sample experienced reliable change; 16.0% of clients reliably improved and 13.1% reliably deteriorated whilst waiting for therapy. Demographic factors were not found to have a significant effect on the change in GD score between assessment and first session. Waiting time was associated with post-therapy outcomes but not to a degree which was meaningful. The majority of individuals (54.4%), regardless of whether they improved or deteriorated whilst waiting for therapy, showed reliable improvement at end of therapy as measured by the CORE-OM. The majority of GD scores remained stable while waiting for therapy; however, 29.1% of secondary care clients experienced either reliable improvement or deterioration. Irrespective of whether they improved, deteriorated or remained unchanged whilst waiting for therapy, most individuals who had a complete end of therapy assessment showed reliable improvements following therapy. There was no significant difference in GD score between assessment and first session recordings. A proportion of clients (29.1%) showed reliable change, either improvement or deterioration, as measured by the GD score while waiting for therapy. Of the individuals with last session CORE-OMs (54.4%) showed significant improvement following therapy regardless of whether or not they experienced change while waiting for therapy. Limitations include: Problems of data quality, the data were from a routine data set and data were lost at each stage of the analysis. A focus on the CORE-OM limits exploration of the subjective experience of waiting for psychotherapy and the impact this has on psychological well-being. © 2014 The British Psychological Society.
Patients' preferences regarding the delivery of health care in a hand surgical practice.
Caggiano, Nicholas M; Fegley, Mark W; Matullo, Kristofer S
2015-12-01
The Patient Protection and Affordable Care Act of 2010 includes patient satisfaction scores in the calculation of reimbursement for services provided. The Medicare and Medicaid Electronic Health Care Record Incentive Program mandate that physicians provide electronic communication with patients. Little data exists regarding patient preferences that might guide the physician adhering to these guidelines. We performed a survey study to examine patients' attitudes regarding the delivery of their health care. We provided an anonymous survey to all outpatient hand surgery patients within a 1-month period at our level I academic center. The survey was structured to ascertain patients' attitudes toward outpatient wait times as well as delivery of patient-specific healthcare-related information. One-hundred and ninety-six surveys were available for review. Of the 196 patients surveyed, 106 (54 %) were between the ages of 45 and 64. Patients aged 25 to 44 were the least willing to wait for an initial outpatient appointment. The majority of patients in all age groups demonstrated unwillingness to wait more than 1 week for evaluation of a new problem. One hundred and forty patients (71 %) were willing to wait longer for an appointment with an upper extremity specialist rather than have an earlier appointment with a non-upper extremity specialist. Wait times of 30 min after arrival in the office were acceptable to 174 patients (89 %) while 40 patients (20 %) were willing to wait an hour or more. Patients preferred a typed handout detailing their specific problem as opposed to referral to a website or an e-mail containing information. The results of our study indicate that patients prefer typed information as opposed to e-mail or websites regarding their health care. Our study also suggests that patients are willing to endure longer wait times if they can be given a sooner appointment, and most prefer a specialist for their problems. These results will provide some guidance to the physician regarding what patients find most appealing.
No-waiting dentine self-etch concept-Merit or hype.
Huang, Xue-Qing; Pucci, César R; Luo, Tao; Breschi, Lorenzo; Pashley, David H; Niu, Li-Na; Tay, Franklin R
2017-07-01
A recently-launched universal adhesive, G-Premio Bond, provides clinicians with the alternative to use the self-etch technique for bonding to dentine without waiting for the adhesive to interact with the bonding substrate (no-waiting self-etch; Japanese brochure), or after leaving the adhesive undisturbed for 10s (10-s self-etch; international brochure). The present study was performed to examine in vitro performance of this new universal adhesive bonded to human coronal dentine using the two alternative self-etch modes. One hundred and ten specimens were bonded using two self-etch application modes and examined with or without thermomechanical cycling (10,000 thermal cycles and 240,000 mechanical cycles) to simulate one year of intraoral functioning. The bonded specimens were sectioned for microtensile bond testing, ultrastructural and nanoleakage examination using transmission electron microscopy. Changes in the composition of mineralised dentine after adhesive application were examined using Fourier transform infrared spectroscopy. Both reduced application time and thermomechanical cycling resulted in significantly lower bond strengths, thinner hybrid layers, and significantly more extensive nanoleakage after thermomechanical cycling. Using the conventional 10-s application time improved bonding performance when compared with the no-waiting self-etch technique. Nevertheless, nanoleakage was generally extensive under all testing parameters employed for examining the adhesive. Although sufficient bond strength to dentine may be achieved using the present universal adhesive in the no-waiting self-etch mode that does not require clinicians to wait prior to polymerisation of the adhesive, this self-etch concept requires further technological refinement before it can be recommended as a clinical technique. Although the surge for cutting application time to increase user friendliness remains the most frequently sought conduit for advancement of dentine bonding technology, the use of the present universal adhesive in the no-waiting self-etch mode may not represent the best use of the adhesive. Published by Elsevier Ltd.
Filho, Herton Luiz Alves Sales; da Mata Sousa, Luiz Claudio Demes; von Glehn, Cristina de Queiroz Carrascosa; da Silva, Adalberto Socorro; dos Santos Neto, Pedro de Alcântara; do Nascimento, Ferraz; de Castro, Adail Fonseca; do Nascimento, Liliane Machado; Kneib, Carolina; Bianchi Cazarote, Helena; Mayumi Kitamura, Daniele; Torres, Juliane Roberta Dias; da Cruz Lopes, Laiane; Barros, Aryela Loureiro; da Silva Edlin, Evelin Nildiane; de Moura, Fernanda Sá Leal; Watanabe, Janine Midori Figueiredo; do Monte, Semiramis Jamil Hadad
2012-06-01
The HLAMatchmaker algorithm, which allows the identification of “safe” acceptable mismatches (AMMs) for recipients of solid organ and cell allografts, is rarely used in part due to the difficulty in using it in the current Excel format. The automation of this algorithm may universalize its use to benefit the allocation of allografts. Recently, we have developed a new software called EpHLA, which is the first computer program automating the use of the HLAMatchmaker algorithm. Herein, we present the experimental validation of the EpHLA program by showing the time efficiency and the quality of operation. The same results, obtained by a single antigen bead assay with sera from 10 sensitized patients waiting for kidney transplants, were analyzed either by conventional HLAMatchmaker or by automated EpHLA method. Users testing these two methods were asked to record: (i) time required for completion of the analysis (in minutes); (ii) number of eplets obtained for class I and class II HLA molecules; (iii) categorization of eplets as reactive or non-reactive based on the MFI cutoff value; and (iv) determination of AMMs based on eplets' reactivities. We showed that although both methods had similar accuracy, the automated EpHLA method was over 8 times faster in comparison to the conventional HLAMatchmaker method. In particular the EpHLA software was faster and more reliable but equally accurate as the conventional method to define AMMs for allografts. The EpHLA software is an accurate and quick method for the identification of AMMs and thus it may be a very useful tool in the decision-making process of organ allocation for highly sensitized patients as well as in many other applications.
Control fast or control smart: When should invading pathogens be controlled?
Thompson, Robin N; Gilligan, Christopher A; Cunniffe, Nik J
2018-02-01
The intuitive response to an invading pathogen is to start disease management as rapidly as possible, since this would be expected to minimise the future impacts of disease. However, since more spread data become available as an outbreak unfolds, processes underpinning pathogen transmission can almost always be characterised more precisely later in epidemics. This allows the future progression of any outbreak to be forecast more accurately, and so enables control interventions to be targeted more precisely. There is also the chance that the outbreak might die out without any intervention whatsoever, making prophylactic control unnecessary. Optimal decision-making involves continuously balancing these potential benefits of waiting against the possible costs of further spread. We introduce a generic, extensible data-driven algorithm based on parameter estimation and outbreak simulation for making decisions in real-time concerning when and how to control an invading pathogen. The Control Smart Algorithm (CSA) resolves the trade-off between the competing advantages of controlling as soon as possible and controlling later when more information has become available. We show-using a generic mathematical model representing the transmission of a pathogen of agricultural animals or plants through a population of farms or fields-how the CSA allows the timing and level of deployment of vaccination or chemical control to be optimised. In particular, the algorithm outperforms simpler strategies such as intervening when the outbreak size reaches a pre-specified threshold, or controlling when the outbreak has persisted for a threshold length of time. This remains the case even if the simpler methods are fully optimised in advance. Our work highlights the potential benefits of giving careful consideration to the question of when to start disease management during emerging outbreaks, and provides a concrete framework to allow policy-makers to make this decision.
Predictors of fecundability and conception waits among the Dogon of Mali.
Strassmann, B I; Warner, J H
1998-02-01
Surprisingly little is known about the mechanisms that underlie variation in female fertility in humans. Data on this topic are nonetheless vital to a number of pragmatic and theoretical enterprises, including population planning, infertility treatment and prevention, and evolutionary ecology. Here we study female fertility by focusing on one component of the interbirth interval: the waiting time to conception during menstrual cycling. Our study population is a Dogon village of 460 people in Mali, West Africa. This population is pronatalist and noncontracepting. In accordance with animist beliefs, the women spend five nights sleeping at a menstrual hut during menses. By censusing the women present at the menstrual huts in the study village on each of 736 consecutive nights, we were able to monitor women's conception waits prospectively. Hormonal profiles confirm the accuracy of the data on conception waits obtained from the menstrual hut census (Strassmann [1996], Behavioral Ecology 7:304-315). Using survival analysis, we identified significant predictors of the waiting time to conception: wife's age (years), husband's age (< 35, 35-49, > 49 years), marital duration (years), gravidity (number of prior pregnancies), and breast-feeding status. Additional variables were not significant, including duration of postpartum amenorrhea, sex of the last child, nutritional status, economic status, polygyny, and marital status (fiancée vs. married). We fit both continuous and discrete time survival models, but the former appeared to be a better choice for these data.
Experience of being a low priority patient during waiting time at an emergency department
Dahlen, Ingrid; Westin, Lars; Adolfsson, Annsofie
2012-01-01
Background Work in the emergency department is characterized by fast and efficient medical efforts to save lives, but can also involve a long waiting time for patients. Patients are given a priority rating upon their arrival in the clinic based on the seriousness of their problem, and nursing care for lower priority patients is given a lower prioritization. Regardless of their medical prioritization, all patients have a right to expect good nursing care while they are waiting. The purpose of this study was to illustrate the experience of the low prioritized patient during their waiting time in the emergency department. Methods A phenomenological hermeneutic research method was used to analyze an interview transcript. Data collection consisted of narrative interviews. The interviewees were 14 patients who had waited more than three hours for surgical, orthopedic, or other medical care. Results The findings resulted in four different themes, ie, being dependent on care, being exposed, being vulnerable, and being secure. Lower priority patients are not paid as much attention by nursing staff. Patients reported feeling powerless, insulted, and humiliated when their care was delayed without their understanding what was happening to them. Not understanding results in exposure that violates self-esteem. Conclusion The goal of the health care provider must be to minimize and prevent suffering, prevent feelings of vulnerability, and to create conditions for optimal patient well being. PMID:22334799
Wang, Chunhua; Liu, Haiyan; Wang, Xiuming; Shen, Xiaochun; Yang, Yingying; Sun, Wenjing; Yan, Qingjun; Cao, Yan; Wang, Xueqin; Lan, Chunhui; Chen, Dongfeng
2015-01-01
Objectives: To investigate whether a 360-degree horizontal turn after oral premedication with simethicone improves the mucosal visibility during gastroendoscopic examination, and to determine the proper time to turn over the patient. Methods: This study involved 993 patients scheduled for gastroendoscopy. Just before gastroendoscopy, after oral premedication with simethicone, patients were randomly assigned to three groups: in Group A, patients waited for 20 min before gastroendoscopy; in Group B, patients were separately waited for 5/10/15/20 min and were then turned 360 degrees just before gastroendoscopy; in Group C, patients were immediately turned 360 degrees and then separately waited for 5/10/15/20 min before examination. The sum of the gastric mucosal visibility scores (MVS) was calculated after the examination. The MVS and proportion of images with higher visibility scores for the mucosal surface. Lower scores indicate better visibility of the mucosal surface. Results: In Groups B and Groups C, when waiting time more than 10 min had lower mean total MVS than Group A. The MVS of four subgroups of Group B were not different from those of Group C. Conclusion: Oral premedication with simethicone and immediately make a body posture change (turning over 360 degrees) then waiting for 10min can increase the image quality during gastroendoscopy and effectively decrease the premedication time. PMID:26064342
Wang, Chunhua; Liu, Haiyan; Wang, Xiuming; Shen, Xiaochun; Yang, Yingying; Sun, Wenjing; Yan, Qingjun; Cao, Yan; Wang, Xueqin; Lan, Chunhui; Chen, Dongfeng
2015-01-01
To investigate whether a 360-degree horizontal turn after oral premedication with simethicone improves the mucosal visibility during gastroendoscopic examination, and to determine the proper time to turn over the patient. This study involved 993 patients scheduled for gastroendoscopy. Just before gastroendoscopy, after oral premedication with simethicone, patients were randomly assigned to three groups: in Group A, patients waited for 20 min before gastroendoscopy; in Group B, patients were separately waited for 5/10/15/20 min and were then turned 360 degrees just before gastroendoscopy; in Group C, patients were immediately turned 360 degrees and then separately waited for 5/10/15/20 min before examination. The sum of the gastric mucosal visibility scores (MVS) was calculated after the examination. The MVS and proportion of images with higher visibility scores for the mucosal surface. Lower scores indicate better visibility of the mucosal surface. In Groups B and Groups C, when waiting time more than 10 min had lower mean total MVS than Group A. The MVS of four subgroups of Group B were not different from those of Group C. Oral premedication with simethicone and immediately make a body posture change (turning over 360 degrees) then waiting for 10min can increase the image quality during gastroendoscopy and effectively decrease the premedication time.
When lives are put on hold: Lengthy asylum processes decrease employment among refugees.
Hainmueller, Jens; Hangartner, Dominik; Lawrence, Duncan
2016-08-01
European governments are struggling with the biggest refugee crisis since World War II, but there exists little evidence regarding how the management of the asylum process affects the subsequent integration of refugees in the host country. We provide new causal evidence about how one central policy parameter, the length of time that refugees wait in limbo for a decision on their asylum claim, affects their subsequent economic integration. Exploiting exogenous variation in wait times and registry panel data covering refugees who applied in Switzerland between 1994 and 2004, we find that one additional year of waiting reduces the subsequent employment rate by 4 to 5 percentage points, a 16 to 23% drop compared to the average rate. This deleterious effect is remarkably stable across different subgroups of refugees stratified by gender, origin, age at arrival, and assigned language region, a pattern consistent with the idea that waiting in limbo dampens refugee employment through psychological discouragement, rather than a skill atrophy mechanism. Overall, our results suggest that marginally reducing the asylum waiting period can help reduce public expenditures and unlock the economic potential of refugees by increasing employment among this vulnerable population.
When lives are put on hold: Lengthy asylum processes decrease employment among refugees
Hainmueller, Jens; Hangartner, Dominik; Lawrence, Duncan
2016-01-01
European governments are struggling with the biggest refugee crisis since World War II, but there exists little evidence regarding how the management of the asylum process affects the subsequent integration of refugees in the host country. We provide new causal evidence about how one central policy parameter, the length of time that refugees wait in limbo for a decision on their asylum claim, affects their subsequent economic integration. Exploiting exogenous variation in wait times and registry panel data covering refugees who applied in Switzerland between 1994 and 2004, we find that one additional year of waiting reduces the subsequent employment rate by 4 to 5 percentage points, a 16 to 23% drop compared to the average rate. This deleterious effect is remarkably stable across different subgroups of refugees stratified by gender, origin, age at arrival, and assigned language region, a pattern consistent with the idea that waiting in limbo dampens refugee employment through psychological discouragement, rather than a skill atrophy mechanism. Overall, our results suggest that marginally reducing the asylum waiting period can help reduce public expenditures and unlock the economic potential of refugees by increasing employment among this vulnerable population. PMID:27493995
Transient modeling in simulation of hospital operations for emergency response.
Paul, Jomon Aliyas; George, Santhosh K; Yi, Pengfei; Lin, Li
2006-01-01
Rapid estimates of hospital capacity after an event that may cause a disaster can assist disaster-relief efforts. Due to the dynamics of hospitals, following such an event, it is necessary to accurately model the behavior of the system. A transient modeling approach using simulation and exponential functions is presented, along with its applications in an earthquake situation. The parameters of the exponential model are regressed using outputs from designed simulation experiments. The developed model is capable of representing transient, patient waiting times during a disaster. Most importantly, the modeling approach allows real-time capacity estimation of hospitals of various sizes and capabilities. Further, this research is an analysis of the effects of priority-based routing of patients within the hospital and the effects on patient waiting times determined using various patient mixes. The model guides the patients based on the severity of injuries and queues the patients requiring critical care depending on their remaining survivability time. The model also accounts the impact of prehospital transport time on patient waiting time.
An Efficient Scheduling Scheme on Charging Stations for Smart Transportation
NASA Astrophysics Data System (ADS)
Kim, Hye-Jin; Lee, Junghoon; Park, Gyung-Leen; Kang, Min-Jae; Kang, Mikyung
This paper proposes a reservation-based scheduling scheme for the charging station to decide the service order of multiple requests, aiming at improving the satisfiability of electric vehicles. The proposed scheme makes it possible for a customer to reduce the charge cost and waiting time, while a station can extend the number of clients it can serve. A linear rank function is defined based on estimated arrival time, waiting time bound, and the amount of needed power, reducing the scheduling complexity. Receiving the requests from the clients, the power station decides the charge order by the rank function and then replies to the requesters with the waiting time and cost it can guarantee. Each requester can decide whether to charge at that station or try another station. This scheduler can evolve to integrate a new pricing policy and services, enriching the electric vehicle transport system.
Estimating Arrhenius parameters using temperature programmed molecular dynamics.
Imandi, Venkataramana; Chatterjee, Abhijit
2016-07-21
Kinetic rates at different temperatures and the associated Arrhenius parameters, whenever Arrhenius law is obeyed, are efficiently estimated by applying maximum likelihood analysis to waiting times collected using the temperature programmed molecular dynamics method. When transitions involving many activated pathways are available in the dataset, their rates may be calculated using the same collection of waiting times. Arrhenius behaviour is ascertained by comparing rates at the sampled temperatures with ones from the Arrhenius expression. Three prototype systems with corrugated energy landscapes, namely, solvated alanine dipeptide, diffusion at the metal-solvent interphase, and lithium diffusion in silicon, are studied to highlight various aspects of the method. The method becomes particularly appealing when the Arrhenius parameters can be used to find rates at low temperatures where transitions are rare. Systematic coarse-graining of states can further extend the time scales accessible to the method. Good estimates for the rate parameters are obtained with 500-1000 waiting times.
NASA Astrophysics Data System (ADS)
Guala, M.; Liu, M.
2017-12-01
The kinematics of sediment particles is investigated by non-intrusive imaging methods to provide a statistical description of bedload transport in conditions near the threshold of motion. In particular, we focus on the cyclic transition between motion and rest regimes to quantify the waiting time statistics inferred to be responsible for anomalous diffusion, and so far elusive. Despite obvious limitations in the spatio-temporal domain of the observations, we are able to identify the probability distributions of the particle step time and length, velocity, acceleration, waiting time, and thus distinguish which quantities exhibit well converged mean values, based on the thickness of their respective tails. The experimental results shown here for four different transport conditions highlight the importance of the waiting time distribution and represent a benchmark dataset for the stochastic modeling of bedload transport.
Anomalous transport in fluid field with random waiting time depending on the preceding jump length
NASA Astrophysics Data System (ADS)
Zhang, Hong; Li, Guo-Hua
2016-11-01
Anomalous (or non-Fickian) transport behaviors of particles have been widely observed in complex porous media. To capture the energy-dependent characteristics of non-Fickian transport of a particle in flow fields, in the present paper a generalized continuous time random walk model whose waiting time probability distribution depends on the preceding jump length is introduced, and the corresponding master equation in Fourier-Laplace space for the distribution of particles is derived. As examples, two generalized advection-dispersion equations for Gaussian distribution and lévy flight with the probability density function of waiting time being quadratic dependent on the preceding jump length are obtained by applying the derived master equation. Project supported by the Foundation for Young Key Teachers of Chengdu University of Technology, China (Grant No. KYGG201414) and the Opening Foundation of Geomathematics Key Laboratory of Sichuan Province, China (Grant No. scsxdz2013009).
Lévy walks with variable waiting time: A ballistic case
NASA Astrophysics Data System (ADS)
Kamińska, A.; Srokowski, T.
2018-06-01
The Lévy walk process for a lower interval of an excursion times distribution (α <1 ) is discussed. The particle rests between the jumps, and the waiting time is position-dependent. Two cases are considered: a rising and diminishing waiting time rate ν (x ) , which require different approximations of the master equation. The process comprises two phases of the motion: particles at rest and in flight. The density distributions for them are derived, as a solution of corresponding fractional equations. For strongly falling ν (x ) , the resting particles density assumes the α -stable form (truncated at fronts), and the process resolves itself to the Lévy flights. The diffusion is enhanced for this case but no longer ballistic, in contrast to the case for the rising ν (x ) . The analytical results are compared with Monte Carlo trajectory simulations. The results qualitatively agree with observed properties of human and animal movements.
ERIC Educational Resources Information Center
Levy, Jacob J.; Thompson-Leonardelli, Kenya; Smith, Nathan Grant; Coleman, M. Nicole
2005-01-01
The present study examined the relationship between attrition after intake and the length of time that clients spent on a waiting list by client race and problem type. Participants were 1,461 clients who completed an initial intake evaluation at a large, Mid-Atlantic counseling center over a 6-year period. Fullfactorial hierarchical logistic…
An inquiry - aesthetics of art in hospitals.
Gates, Jillian
2008-09-01
Historically, art has served a significant purpose within hospital waiting rooms. However, in recent times we have experienced cuts in funding and less interest in improving the aesthetic of art displayed in Australian hospitals. This article briefly discusses the history of art in hospitals and explores a methodology for researching the preference of Australian patients today. Potentially, Australians waiting in hospitals and medical clinics could benefit from art works that reflect their preferences; this may help to ease the pain, anxiety, and boredom of waiting.
Marchandise, Sébastien; Scavée, Christophe; Barbraud, Cynthia; de Meester de Ravenstein, Christophe; Balola Bagalwa, Mittérand; Goesaert, Cédric; Reis-Pinheiro, Ivone; le Polain de Waroux, Jean-Benoit
2017-12-01
The aim of this study was to determine the rate of recurrent atrial flutter (AFl) after isolated cavotricuspid isthmus (CTI) ablation and to evaluate the impact of a waiting period with the search for early resumption of the CTI block on the long-term outcome. Three hundred and nineteen consecutive patients referred for typical AFl ablation were randomly assigned to CTI ablation with continuous reevaluation of the CTI block during 30 minutes and early reablation if needed (waiting time [WT] + group, n = 155) or to CTI ablation with no waiting period after proven bidirectional CTI block (WT - group, n = 164). All patients were regularly followed-up. In the WT+ group, 10 patients (6%) presented a recovery across the CTI (time to recovery: 17 ± 7') and were reablated at the end of the waiting period. After a median follow-up of 21 months, the rate of recurrent AFl was significantly higher in the WT - group as compared to the WT+ group (11.6% [19/164] vs 2.5% [4/155], respectively; P = 0.007). However, no significant differences in the subsequent rate of AF were observed between the two groups (29% [WT -] vs 32% [WT+], P = 0.66). During the follow-up, 28 patients from the WT - group underwent a second ablation procedure (16 AFl redo and 12 AF ablation) versus 10 patients form the WT+ group (three AFl redo and seven AF ablation). Waiting 30 minutes after CTI ablation to check for early resumption and early reablation allows for decreasing significantly the rate of recurrent atrial flutter. © 2017 Wiley Periodicals, Inc.
Devasahayam, Raj; Georges, Pierre; Hodge, Christopher; Treloggen, Jane; Cooper, Simon; Petsoglou, Con; Sutton, Gerard; Zhu, Meidong
2016-09-01
Organ Culture corneal storage offers an extended storage time and increased donor pool and tissue assessment opportunities. In September 2011, the Lions New South Wales Eye Bank (LNSWEB) moved from hypothermic storage to Organ Culture corneal storage. This study evaluates the impact of implementation of Organ Culture on donor eye retrieval and the corneal transplant waiting list over a 3 year period in NSW, Australia. Retrospective review of the LNSWEB data from September 2011 to August 2014. Tissue collection, waiting list and tissue utilization data were recorded. The data from September 2008 to August 2011 for Optisol-GS storage was used for comparison. The annual donor and cornea collection rate increased 35 % and 44 % respectively with Organ Culture compared to Optisol-GS storage. The utilization rate of corneal tissue increased from 73.4 % with hypothermic storage to 77.2 % with Organ Culture storage. The transplant wait list decreased by 77.3 % from September 2011 to August 2014 and correlated with the increased rate of corneal transplantation (r = -0.9381, p < 0.0001). No other factors impacting the wait list changed over this period. Corneas not used from either storage method were due to unacceptable endothelial cell density/viability. The contamination rate of corneas stored in Organ Culture medium was low at 1.74 %. The Organ Culture storage method increases the corneal donor pool available to Eye banks. The practical benefits of the extended storage time and increased donor assessment opportunities have directly led to an increase in corneal utilization rate and a significant decrease in recipient wait list time.
Fosby, Bjarte; Melum, Espen; Bjøro, Kristian; Bennet, William; Rasmussen, Allan; Andersen, Ina Marie; Castedal, Maria; Olausson, Michael; Wibeck, Christina; Gotlieb, Mette; Gjertsen, Henrik; Toivonen, Leena; Foss, Stein; Makisalo, Heikki; Nordin, Arno; Sanengen, Truls; Bergquist, Annika; Larsson, Marie E.; Soderdahl, Gunnar; Nowak, Greg; Boberg, Kirsten Muri; Isoniemi, Helena; Keiding, Susanne; Foss, Aksel; Line, Pål-Dag; Friman, Styrbjörn; Schrumpf, Erik; Ericzon, Bo-Göran; Höckerstedt, Krister; Karlsen, Tom H.
2015-01-01
Abstract Aim and background. The Nordic Liver Transplant Registry (NLTR) accounts for all liver transplants performed in the Nordic countries since the start of the transplant program in 1982. Due to short waiting times, donor liver allocation has been made without considerations of the model of end-stage liver disease (MELD) score. We aimed to summarize key outcome measures and developments for the activity up to December 2013. Materials and methods. The registry is integrated with the operational waiting-list and liver allocation system of Scandiatransplant (www.scandiatransplant.org) and accounted at the end of 2013 for 6019 patients out of whom 5198 were transplanted. Data for recipient and donor characteristics and relevant end-points retransplantation and death are manually curated on an annual basis to allow for statistical analysis and the annual report. Results. Primary sclerosing cholangitis, acute hepatic failure, alcoholic liver disease, primary biliary cirrhosis and hepatocellular carcinoma are the five most frequent diagnoses (accounting for 15.3%, 10.8%, 10.6%, 9.3% and 9.0% of all transplants, respectively). Median waiting time for non-urgent liver transplantation during the last 10-year period was 39 days. Outcome has improved over time, and for patients transplanted during 2004–2013, overall one-, five- and 10-year survival rates were 91%, 80% and 71%, respectively. In an intention-to-treat analysis, corresponding numbers during the same time period were 87%, 75% and 66%, respectively. Conclusion. The liver transplant program in the Nordic countries provides comparable outcomes to programs with a MELD-based donor liver allocation system. Unique features comprise the diagnostic spectrum, waiting times and the availability of an integrated waiting list and transplant registry (NLTR). PMID:25959101
Fosby, Bjarte; Melum, Espen; Bjøro, Kristian; Bennet, William; Rasmussen, Allan; Andersen, Ina Marie; Castedal, Maria; Olausson, Michael; Wibeck, Christina; Gotlieb, Mette; Gjertsen, Henrik; Toivonen, Leena; Foss, Stein; Makisalo, Heikki; Nordin, Arno; Sanengen, Truls; Bergquist, Annika; Larsson, Marie E; Soderdahl, Gunnar; Nowak, Greg; Boberg, Kirsten Muri; Isoniemi, Helena; Keiding, Susanne; Foss, Aksel; Line, Pål-Dag; Friman, Styrbjörn; Schrumpf, Erik; Ericzon, Bo-Göran; Höckerstedt, Krister; Karlsen, Tom H
2015-06-01
The Nordic Liver Transplant Registry (NLTR) accounts for all liver transplants performed in the Nordic countries since the start of the transplant program in 1982. Due to short waiting times, donor liver allocation has been made without considerations of the model of end-stage liver disease (MELD) score. We aimed to summarize key outcome measures and developments for the activity up to December 2013. The registry is integrated with the operational waiting-list and liver allocation system of Scandiatransplant (www.scandiatransplant.org) and accounted at the end of 2013 for 6019 patients out of whom 5198 were transplanted. Data for recipient and donor characteristics and relevant end-points retransplantation and death are manually curated on an annual basis to allow for statistical analysis and the annual report. Primary sclerosing cholangitis, acute hepatic failure, alcoholic liver disease, primary biliary cirrhosis and hepatocellular carcinoma are the five most frequent diagnoses (accounting for 15.3%, 10.8%, 10.6%, 9.3% and 9.0% of all transplants, respectively). Median waiting time for non-urgent liver transplantation during the last 10-year period was 39 days. Outcome has improved over time, and for patients transplanted during 2004-2013, overall one-, five- and 10-year survival rates were 91%, 80% and 71%, respectively. In an intention-to-treat analysis, corresponding numbers during the same time period were 87%, 75% and 66%, respectively. The liver transplant program in the Nordic countries provides comparable outcomes to programs with a MELD-based donor liver allocation system. Unique features comprise the diagnostic spectrum, waiting times and the availability of an integrated waiting list and transplant registry (NLTR).
Colour Consideration for Waiting areas in hospitals
NASA Astrophysics Data System (ADS)
Zraati, Parisa
2012-08-01
Colour is one the most important factors in the nature that can have some affects on human behaviour. Many years ago, it was proven that using colour in public place can have some affect on the users. Depend of the darkness and lightness; it can be vary from positive to negative. The research will mainly focus on the colour and psychological influences and physical factors. The statement of problem in this research is what is impact of colour usually applied to waiting area? The overall aim of the study is to explore the visual environment of hospitals and to manage the colour psychological effect of the hospital users in the waiting area by creating a comfortable, pleasant and cozy environment for users while spend their time in waiting areas. The analysisconcentrate on satisfaction and their interesting regarding applied colour in two private hospital waiting area in Malaysia.
Weight-ing: the experience of waiting on weight loss.
Glenn, Nicole M
2013-03-01
Perhaps we want to be perfect, strive for health, beauty, and the admiring gaze of others. Maybe we desire the body of our youth, the "healthy" body, the body that has just the right fit. Regardless of the motivation, we might find ourselves striving, wanting, and waiting on weight loss. What is it to wait on weight loss? I explore the meaning of this experience-as-lived using van Manen's guide to phenomenological reflection and writing. Weight has become an increasing focus of contemporary culture, demonstrated, for example, by a growing weight-loss industry and global obesity "epidemic." Weight has become synonymous with health status, and weight loss with "healthier." I examine the weight wait through experiences of the common and uncommon, considering relations to time, body, space, and the other with the aim of evoking a felt, embodied, emotive understanding of the meaning of waiting on weight loss. I also discuss the implications of the findings.
The Flex Track: Flexible Partitioning between Low- and High-Acuity Areas of an Emergency Department
Laker, Lauren F.; Froehle, Craig M.; Lindsell, Christopher J.; Ward, Michael J.
2014-01-01
Study Objective EDs with both low- and high-acuity treatment areas often have fixed allocation of resources, regardless of demand. We demonstrate the utility of discrete-event simulation to evaluate flexible partitioning between low- and high-acuity ED areas to identify the best operational strategy for subsequent implementation. Methods A discrete-event simulation was used to model patient flow through a 50-bed, urban, teaching ED that handles 85,000 patient visits annually. The ED has historically allocated ten beds to a Fast Track for low-acuity patients. We estimated the effect of a Flex Track policy, which involved switching up to five of these Fast Track beds to serving both low- and high-acuity patients, on patient waiting times. When the high-acuity beds were not at capacity, low-acuity patients were given priority access to flexible beds. Otherwise, high-acuity patients were given priority access to flexible beds. Wait times were estimated for patients by disposition and emergency severity index (ESI) score. Results A Flex Track policy using three flexible beds produced the lowest mean patient waiting of 30.9 (95% CI 30.6–31.2) minutes. The typical Fast Track approach of rigidly separating high- and low–acuity beds produced a mean patient wait time of 40.6 (95% CI 40.2–50.0) minutes, 31% higher than the three-bed Flex Track. A completely flexible ED, where all beds can accommodate any patient, produced mean wait times of 35.1 (95% CI 34.8–35.4) minutes. The results from the three-bed Flex Track scenario were robust, performing well across a range of scenarios involving higher and lower patient volumes and care durations. Conclusion Using discrete-event simulation, we have shown that adding some flexibility into bed allocation between low- and high-acuity can provide substantial reductions in overall patient waiting and a more efficient ED. PMID:24954578
Ellerbe, Laura S; Manfredi, Luisa; Gupta, Shalini; Phelps, Tyler E; Bowe, Thomas R; Rubinsky, Anna D; Burden, Jennifer L; Harris, Alex H S
2017-04-04
In the U.S. Department of Veterans Affairs (VA), residential treatment programs are an important part of the continuum of care for patients with a substance use disorder (SUD). However, a limited number of program-specific measures to identify quality gaps in SUD residential programs exist. This study aimed to: (1) Develop metrics for two pre-admission processes: Wait Time and Engagement While Waiting, and (2) Interview program management and staff about program structures and processes that may contribute to performance on these metrics. The first aim sought to supplement the VA's existing facility-level performance metrics with SUD program-level metrics in order to identify high-value targets for quality improvement. The second aim recognized that not all key processes are reflected in the administrative data, and even when they are, new insight may be gained from viewing these data in the context of day-to-day clinical practice. VA administrative data from fiscal year 2012 were used to calculate pre-admission metrics for 97 programs (63 SUD Residential Rehabilitation Treatment Programs (SUD RRTPs); 34 Mental Health Residential Rehabilitation Treatment Programs (MH RRTPs) with a SUD track). Interviews were then conducted with management and front-line staff to learn what factors may have contributed to high or low performance, relative to the national average for their program type. We hypothesized that speaking directly to residential program staff may reveal innovative practices, areas for improvement, and factors that may explain system-wide variability in performance. Average wait time for admission was 16 days (SUD RRTPs: 17 days; MH RRTPs with a SUD track: 11 days), with 60% of Veterans waiting longer than 7 days. For these Veterans, engagement while waiting occurred in an average of 54% of the waiting weeks (range 3-100% across programs). Fifty-nine interviews representing 44 programs revealed factors perceived to potentially impact performance in these domains. Efficient screening processes, effective patient flow, and available beds were perceived to facilitate shorter wait times, while lack of beds, poor staffing levels, and lengths of stay of existing patients were thought to lengthen wait times. Accessible outpatient services, strong patient outreach, and strong encouragement of pre-admission outpatient treatment emerged as facilitators of engagement while waiting; poor staffing levels, socioeconomic barriers, and low patient motivation were viewed as barriers. Metrics for pre-admission processes can be helpful for monitoring residential SUD treatment programs. Interviewing program management and staff about drivers of performance metrics can play a complementary role by identifying innovative and other strong practices, as well as high-value targets for quality improvement. Key facilitators of high-performing facilities may offer programs with lower performance useful strategies to improve specific pre-admission processes.
Info card for surgery waiting room improves satisfaction.
2015-11-01
A hospital is reporting improved patient satisfaction from providing an information card in the surgery department. The card includes expected wait times. The card is provided by the patient transport team. Telephone numbers are included for more information. Staff update family members hourly during surgery.
Palvannan, R Kannapiran; Teow, Kiok Liang
2012-04-01
Patient queues are prevalent in healthcare and wait time is one measure of access to care. We illustrate Queueing Theory-an analytical tool that has provided many insights to service providers when designing new service systems and managing existing ones. This established theory helps us to quantify the appropriate service capacity to meet the patient demand, balancing system utilization and the patient's wait time. It considers four key factors that affect the patient's wait time: average patient demand, average service rate and the variation in both. We illustrate four basic insights that will be useful for managers and doctors who manage healthcare delivery systems, at hospital or department level. Two examples from local hospitals are shown where we have used queueing models to estimate the service capacity and analyze the impact of capacity configurations, while considering the inherent variation in healthcare.
Dynamics of morphological evolution in experimental Escherichia coli populations.
Cui, F; Yuan, B
2016-08-30
Here, we applied a two-stage clonal expansion model of morphological (cell-size) evolution to a long-term evolution experiment with Escherichia coli. Using this model, we derived the incidence function of the appearance of cell-size stability, the waiting time until this morphological stability, and the conditional and unconditional probabilities of morphological stability. After assessing the parameter values, we verified that the calculated waiting time was consistent with the experimental results, demonstrating the effectiveness of the two-stage model. According to the relative contributions of parameters to the incidence function and the waiting time, cell-size evolution is largely determined by the promotion rate, i.e., the clonal expansion rate of selectively advantageous organisms. This rate plays a prominent role in the evolution of cell size in experimental populations, whereas all other evolutionary forces were found to be less influential.
Simulating an underwater vehicle self-correcting guidance system with Simulink
NASA Astrophysics Data System (ADS)
Fan, Hui; Zhang, Yu-Wen; Li, Wen-Zhe
2008-09-01
Underwater vehicles have already adopted self-correcting directional guidance algorithms based on multi-beam self-guidance systems, not waiting for research to determine the most effective algorithms. The main challenges facing research on these guidance systems have been effective modeling of the guidance algorithm and a means to analyze the simulation results. A simulation structure based on Simulink that dealt with both issues was proposed. Initially, a mathematical model of relative motion between the vehicle and the target was developed, which was then encapsulated as a subsystem. Next, steps for constructing a model of the self-correcting guidance algorithm based on the Stateflow module were examined in detail. Finally, a 3-D model of the vehicle and target was created in VRML, and by processing mathematical results, the model was shown moving in a visual environment. This process gives more intuitive results for analyzing the simulation. The results showed that the simulation structure performs well. The simulation program heavily used modularization and encapsulation, so has broad applicability to simulations of other dynamic systems.
Guo, Hongwei; Gao, Ziyou; Yang, Xiaobao; Jiang, Xiaobei
2011-02-01
Pedestrian violation is a major cause of traffic accidents involving pedestrians. The research objectives were to investigate the relationship between waiting duration and pedestrian violation and to provide a qualitative and quantitative analysis of the effects of human factors and external environmental factors on street-crossing behavior. Pedestrians' street-crossing behavior was examined by modeling the waiting duration at signalized crosswalk. Pedestrian waiting duration was collected by video cameras and it was assigned as censored and uncensored data to distinguish between normal crossing and violating crossing. A nonparametric baseline duration model was introduced, and variables revealing personal characteristics, traffic conditions, and trip features were defined as covariates to describe the effects of internal and external factors. Pedestrians' crossing behaviors represented positive duration dependence that the longer the waiting time elapsed the more likely pedestrians would end the wait soon. The violation inclination of most pedestrians increased with the increasing waiting duration, but about 10 percent of pedestrians were at high risk of violation to cross the street. About half of pedestrians would still obey the traffic rules even after waiting for 50 s by the street. Human factors and the external environment played an important role in street-crossing behavior, especially for factors that involved pedestrians' subjective willingness. The street-crossing behavior of pedestrians was time dependent. Pedestrians behave differently under the effects of various factors. Pedestrian safety interventions that aim at reducing pedestrian injuries may need to consider these effects. The pedestrians' behavioral modifications, such as enhancing the safety awareness, might be the most efficient means to reducing the likelihood of pedestrian violation, though environmental modifications also worked well in improving pedestrian safety.
STEPS: lean thinking, theory of constraints and identifying bottlenecks in an emergency department.
Ryan, A; Hunter, K; Cunningham, K; Williams, J; O'Shea, H; Rooney, P; Hickey, F
2013-04-01
This study aimed to identify the bottlenecks in patients' journeys through an emergency department (ED). For each stage of the patient journey, the average times were compared between two groups divided according to the four hour time frame and disproportionate delays were identified using a significance test These bottlenecks were evaluated with reference to a lean thinking value-stream map and the five focusing steps of the theory of constraints. A total of 434 (72.5%) ED patients were tracked over one week. Logistic regression showed that patients who had radiological tests, blood tests or who were admitted were 4.4, 4.1 and 7.7 times more likely, respectively, to stay over four hours in the ED than those who didn't The stages that were significantly delayed were the time spent waiting for radiology (p = 0.001), waiting for the in-patient team (p = 0.004), waiting for a bed (p < 0.001) and ED doctor turnaround time (p < 0.001).
McKevitt, Elaine; Dingee, Carol; Warburton, Rebecca; Pao, Jin-Si; Brown, Carl J; Wilson, Christine; Kuusk, Urve
2018-05-01
Concern has been raised about delays for patients presenting with breast symptoms in Canada. Our objective was to determine if our Rapid Access Breast Clinic (RABC) improved care for patients presenting with breast symptoms compared to the traditional system (TS). A retrospective chart review tabulated demographic, surgical, pathology and radiologic information. Wait times to care were determined for patients presenting with symptomatic and screen detected breast problems. Time from presentation to surgeon evaluation was shorter in the RABC group for patients with breast symptoms (81 vs 35 days, p < .0001) and abnormal screens (72 vs 40 days, p = .092). Cancer patients with abnormal screens had shorter wait times than patients with breast symptoms in the TS (47 vs 70 days, p = .036). Coordination of imaging and clinical care reduces wait times in patients with both abnormal screening mammograms and symptomatic breast presentations and should be expanded in our province. Copyright © 2018 Elsevier Inc. All rights reserved.
Improving ED efficiency to capture additional revenue.
Mandavia, Sujal; Samaniego, Loretta
2016-06-01
An increase in the number of patients visiting emergency departments (EDs) presents an opportunity for additional revenue if hospitals take four steps to optimize resources: Streamline the patient pathway and reduce the amount of time each patient occupies a bed in the ED. Schedule staff according to the busy and light times for patient arrivals. Perform registration and triage bedside, reducing initial wait times. Create an area for patients to wait for test results so beds can be freed up for new arrivals.
NASA Technical Reports Server (NTRS)
Ziegler, C.; Schilling, D. L.
1977-01-01
Two networks consisting of single server queues, each with a constant service time, are considered. The external inputs to each network are assumed to follow some general probability distribution. Several interesting equivalencies that exist between the two networks considered are derived. This leads to the introduction of an important concept in delay decomposition. It is shown that the waiting time experienced by a customer can be decomposed into two basic components called self delay and interference delay.
Waiting-time distributions of magnetic discontinuities: clustering or Poisson process?
Greco, A; Matthaeus, W H; Servidio, S; Dmitruk, P
2009-10-01
Using solar wind data from the Advanced Composition Explorer spacecraft, with the support of Hall magnetohydrodynamic simulations, the waiting-time distributions of magnetic discontinuities have been analyzed. A possible phenomenon of clusterization of these discontinuities is studied in detail. We perform a local Poisson's analysis in order to establish if these intermittent events are randomly distributed or not. Possible implications about the nature of solar wind discontinuities are discussed.
Waiting-time distributions of magnetic discontinuities: Clustering or Poisson process?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greco, A.; Matthaeus, W. H.; Servidio, S.
2009-10-15
Using solar wind data from the Advanced Composition Explorer spacecraft, with the support of Hall magnetohydrodynamic simulations, the waiting-time distributions of magnetic discontinuities have been analyzed. A possible phenomenon of clusterization of these discontinuities is studied in detail. We perform a local Poisson's analysis in order to establish if these intermittent events are randomly distributed or not. Possible implications about the nature of solar wind discontinuities are discussed.
2012-12-01
STATEMENT Approved for public release; distribution is unlimited 12b. DISTRIBUTION CODE A 13. ABSTRACT (maximum 200 words) Customer Wait Time ( CWT ...inventory level, thereby increasing the material readiness of the operating forces. Intuitively, decreasing CWT increases operational availability (Ao...and CWT has led to arbitrary stock policies that do not account for the cost and benefit they provide. This project centers on monetizing the
Sustainability: orthopaedic surgery wait time management strategies.
Amar, Claudia; Pomey, Marie-Pascale; SanMartin, Claudia; De Coster, Carolyn; Noseworthy, Tom
2015-01-01
The purpose of this paper is to examine Canadian organizational and systemic factors that made it possible to keep wait times within federally established limits for at least 18 months. The research design is a multiple cases study. The paper selected three cases: Case 1 - staff were able to maintain compliance with requirements for more than 18 months; Case 2 - staff were able to meet requirements for 18 months, but unable to sustain this level; Case 3 - staff were never able to meet the requirements. For each case the authors interviewed persons involved in the strategies and collected documents. The paper analysed systemic and organizational-level factors; including governance and leadership, culture, resources, methods and tools. Findings indicate that the hospital that was able to maintain compliance with the wait time requirements had specific characteristics: an exclusive mandate to do only hip and knee replacement surgery; motivated staff who were not distracted by other concerns; and a strong team spirit. The authors' research highlights an important gradient between three cases regarding the factors that sustain waiting times. The paper show that the hospital factory model seems attractive in a super-specialized surgery context. However, patients are selected for simple surgeries, without complications, and so this cannot be considered a unique model.
Rosengard, C; Adler, N; Millstein, S; Gurvey, J; Ellen, J
2004-01-01
Objectives: To examine the amount of time adolescents waited to have intercourse with past partners (main and casual), and intentions to delay with future partners. To determine psychosocial factors which predict delay intentions among adolescent males and females with future partners (main and casual). Methods: Adolescent STD clinic attendees were approached before clinical appointments to participate in an interview. Data from 205 participants who had previous experience with both main and casual partners were used in the current study. Results: Adolescents waited less time to have intercourse with most recent casual than with most recent main partners (χ2 = 31.97, p<0.0001). The amount of time waited with past partners was shorter than intended time to wait in future relationships (medians of 1 month v 2 months (main) (t = 3.47, p<0.0010; medians of 2 weeks v 1 month (casual) (t = 6.14, p<0.0001)). Factors influencing intentions to delay intercourse with future main partners differed by sex; males were negatively influenced by importance of sex in relationships, while females were positively influenced by importance of intimacy in relationships, perceived risk of STDs, and health values. Conclusions: Implications for designing interventions for adolescent males and females are discussed. PMID:15054176
Scott, Anthony; Yong, Jongsay
2015-04-01
This paper evaluates the effect of introducing two new workforce roles under a pilot program conducted in Victoria, Australia. The trial took place at a regional hospital's emergency department (ED) between 1 July 2008 and 30 June 2009. The evaluation is based on three outcome measures: waiting time (in minutes) at ED before treatment; proportion of presentations with waiting time on target; and length of stay (in days), for ED presentations that led to in-patient admissions. The technique of difference-in-differences analysis is used. A total of 142,980 patient records from the pilot hospital and three comparison hospitals were extracted from the Victorian Emergency Minimum Dataset (VEMD). Further, 21,925 records of patients whose ED presentations led to in-patient admissions were extracted from the Victorian Admitted Episodes Dataset (VAED). The evaluation finds the piloted roles have lowered waiting time and raised the proportion of on-target presentations. These effects were found to be the strongest for less urgent triage categories. However, the evidence on in-patient length of stay was mixed. The results provide positive evidence that new workforce roles can be effective in improving the efficiency of emergency care delivery. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Do targets matter? A comparison of English and Welsh National Health priorities.
Hauck, Katharina; Street, Andrew
2007-03-01
National priorities and performance management regimes in the National Health Services of England and Wales diverged following devolution, most notably with respect to the use of waiting time targets, which have been progressively strengthened in England but were abandoned in Wales in the immediate post-devolution period. We analyse routine data collected over a six-year period from three English and one Welsh hospital trust close to the English-Welsh border to ascertain whether: (a) there is evidence of differential performance over time that relates to the country where the hospital is located; (b) within each hospital, there is evidence that English and Welsh patients faced different waiting times. Over the period the English hospitals recorded increased levels of activity, undertook proportionately more day case activity, and mortality rates fell. Activity levels remained constant in Wales, the proportion of day case activity fell, proportionately more non-elective patients were admitted, and mortality rates rose. There is partial evidence that English patients faced lower waiting times than their Welsh counterparts and were more likely to be admitted within a target waiting period. The stronger performance management regime operating in England appears to have contributed to higher levels of performance in the English hospitals over the period. Copyright (c) 2006 John Wiley & Sons, Ltd.
Breton, Mylaine; Green, Michael; Kreindler, Sara; Sutherland, Jason; Jbilou, Jalila; Wong, Sabrina T; Shaw, Jay; Crooks, Valorie A; Contandriopoulos, Damien; Smithman, Mélanie Ann; Brousselle, Astrid
2017-01-21
Having a regular primary care provider (i.e., family physician or nurse practitioner) is widely considered to be a prerequisite for obtaining healthcare that is timely, accessible, continuous, comprehensive, and well-coordinated with other parts of the healthcare system. Yet, 4.6 million Canadians, approximately 15% of Canada's population, are unattached; that is, they do not have a regular primary care provider. To address the critical need for attachment, especially for more vulnerable patients, six Canadian provinces have implemented centralized waiting lists for unattached patients. These waiting lists centralize unattached patients' requests for a primary care provider in a given territory and match patients with providers. From the little information we have on each province's centralized waiting list, we know the way they work varies significantly from province to province. The main objective of this study is to compare the different models of centralized waiting lists for unattached patients implemented in six provinces of Canada to each other and to available scientific knowledge to make recommendations on ways to improve their design in an effort to increase attachment of patients to a primary care provider. A logic analysis approach developed in three steps will be used. Step 1: build logic models that describe each province's centralized waiting list through interviews with key stakeholders in each province; step 2: develop a conceptual framework, separate from the provincially informed logic models, that identifies key characteristics of centralized waiting lists for unattached patients and factors influencing their implementation through a literature review and interviews with experts; step 3: compare the logic models to the conceptual framework to make recommendations to improve centralized waiting lists in different provinces during a pan Canadian face-to-face exchange with decision-makers, clinicians and researchers. This study is based on an inter-provincial learning exchange approach where we propose to compare centralized waiting lists and analyze variations in strategies used to increase attachment to a regular primary care provider. Fostering inter-provincial healthcare systems connectivity to improve centralized waiting lists' practices across Canada can lever attachment to a regular provider for timely access to continuous, comprehensive and coordinated healthcare for all Canadians and particular for those who are vulnerable.
Especially for Teens: You and Your Sexuality
... you feel that it will make you a “real” woman What if I decide to wait and someone tries to pressure me into sex? If you have decided to wait, think about what you will say ahead of time if someone pressures you to have sex. The ...
Empirical and theoretical analysis of complex systems
NASA Astrophysics Data System (ADS)
Zhao, Guannan
This thesis is an interdisciplinary work under the heading of complexity science which focuses on an arguably common "hard" problem across physics, finance and biology [1], to quantify and mimic the macroscopic "emergent phenomenon" in large-scale systems consisting of many interacting "particles" governed by microscopic rules. In contrast to traditional statistical physics, we are interested in systems whose dynamics are subject to feedback, evolution, adaption, openness, etc. Global financial markets, like the stock market and currency market, are ideal candidate systems for such a complexity study: there exists a vast amount of accurate data, which is the aggregate output of many autonomous agents continuously competing with each other. We started by examining the ultrafast "mini flash crash (MFC)" events in the US stock market. An abrupt system-wide composition transition from a mixed human machine phase to a new all-machine phase is uncovered, and a novel theory developed to explain this observation. Then in the study of FX market, we found an unexpected variation in the synchronicity of price changes in different market subsections as a function of the overall trading activity. Several survival models have been tested in analyzing the distribution of waiting times to the next price change. In the region of long waiting-times, the distribution for each currency pair exhibits a power law with exponent in the vicinity of 3.5. By contrast, for short waiting times only, the market activity can be mimicked by the fluctuations emerging from a finite resource competition model containing multiple agents with limited rationality (so called El Farol Model). Switching to the biomedical domain, we present a minimal mathematical model built around a co-evolving resource network and cell population, yielding good agreement with primary tumors in mice experiment and with clinical metastasis data. In the quest to understand contagion phenomena in systems where social group structures evolve on a similar timescale to individual level transmission, we investigated the process of transmission through a model population comprising of social groups which follow simple dynamical rules for growth and break-up, and the profiles produced bear a striking resemblance to empirical data obtained from social, financial and biological systems. Finally, for better implementation of a widely accepted power law test algorithm, we have developed a fast testing procedure using parallel computation.
Effect of match-run frequencies on the number of transplants and waiting times in kidney exchange.
Ashlagi, Itai; Bingaman, Adam; Burq, Maximilien; Manshadi, Vahideh; Gamarnik, David; Murphey, Cathi; Roth, Alvin E; Melcher, Marc L; Rees, Michael A
2018-05-01
Numerous kidney exchange (kidney paired donation [KPD]) registries in the United States have gradually shifted to high-frequency match-runs, raising the question of whether this harms the number of transplants. We conducted simulations using clinical data from 2 KPD registries-the Alliance for Paired Donation, which runs multihospital exchanges, and Methodist San Antonio, which runs single-center exchanges-to study how the frequency of match-runs impacts the number of transplants and the average waiting times. We simulate the options facing each of the 2 registries by repeated resampling from their historical pools of patient-donor pairs and nondirected donors, with arrival and departure rates corresponding to the historical data. We find that longer intervals between match-runs do not increase the total number of transplants, and that prioritizing highly sensitized patients is more effective than waiting longer between match-runs for transplanting highly sensitized patients. While we do not find that frequent match-runs result in fewer transplanted pairs, we do find that increasing arrival rates of new pairs improves both the fraction of transplanted pairs and waiting times. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.
Sedlack, Jeffrey D
2010-01-01
Surgeons have been slow to incorporate industrial reliability techniques. Process control methods were applied to surgeon waiting time between cases, and to length of stay (LOS) after colon surgery. Waiting times between surgeries were evaluated by auditing the operating room records of a single hospital over a 1-month period. The medical records of 628 patients undergoing colon surgery over a 5-year period were reviewed. The average surgeon wait time between cases was 53 min, and the busiest surgeon spent 291/2 hr in 1 month waiting between surgeries. Process control charting demonstrated poor overall control of the room turnover process. Average LOS after colon resection also demonstrated very poor control. Mean LOS was 10 days. Weibull's conditional analysis revealed a conditional LOS of 9.83 days. Serious process management problems were identified in both analyses. These process issues are both expensive and adversely affect the quality of service offered by the institution. Process control mechanisms were suggested or implemented to improve these surgical processes. Industrial reliability and quality management tools can easily and effectively identify process control problems that occur on surgical services. © 2010 National Association for Healthcare Quality.
Warnke, Tom; Reinhardt, Oliver; Klabunde, Anna; Willekens, Frans; Uhrmacher, Adelinde M
2017-10-01
Individuals' decision processes play a central role in understanding modern migration phenomena and other demographic processes. Their integration into agent-based computational demography depends largely on suitable support by a modelling language. We are developing the Modelling Language for Linked Lives (ML3) to describe the diverse decision processes of linked lives succinctly in continuous time. The context of individuals is modelled by networks the individual is part of, such as family ties and other social networks. Central concepts, such as behaviour conditional on agent attributes, age-dependent behaviour, and stochastic waiting times, are tightly integrated in the language. Thereby, alternative decisions are modelled by concurrent processes that compete by stochastic race. Using a migration model, we demonstrate how this allows for compact description of complex decisions, here based on the Theory of Planned Behaviour. We describe the challenges for the simulation algorithm posed by stochastic race between multiple concurrent complex decisions.
OPTN/SRTR 2016 Annual Data Report: Lung.
Valapour, M; Lehr, C J; Skeans, M A; Smith, J M; Carrico, R; Uccellini, K; Lehman, R; Robinson, A; Israni, A K; Snyder, J J; Kasiske, B L
2018-01-01
In 2016, 2692 candidates aged 12 years or older were added to the lung transplant waiting list; 2345 transplants were performed, the largest number of any prior year. The median waiting time for listed candidates in 2016 was 2.5 months, and waiting times were shortest for group D candidates. The transplant rate increased to 191.9 transplants per 100 waitlist years in 2016, with a slight decrease in waitlist mortality to 15.1 deaths per 100 waitlist years. Short-term survival continued to improve, with a 6-month death rate of 6.6% and a 1-year death rate of 10.8% among recipients in 2015 compared with 8.0% and 13.3%, respectively, among recipients in 2014. Long-term survival rates remained unchanged; 55.6% of recipients were alive at 5 years. In 2016, 23 new candidates aged 0-11 years were added to the waiting list and 16 lung transplants were performed. Incidence of posttransplant mortality for lung transplant recipients aged 0-11 years who underwent transplant in 2014-2015 was 13.8% at 6 months and 19.6% at 1 year. Changes in waitlist and transplant demographic features continued to evolve following implementation of the revised lung allocation score in 2015. Some early trends that may be attributable to the revised LAS are shorter waiting times, stabilization of the number of group D candidates listed for transplant, and convergence of LAS with lower prevalence of extremely high scores. .
The flex track: flexible partitioning between low- and high-acuity areas of an emergency department.
Laker, Lauren F; Froehle, Craig M; Lindsell, Christopher J; Ward, Michael J
2014-12-01
Emergency departments (EDs) with both low- and high-acuity treatment areas often have fixed allocation of resources, regardless of demand. We demonstrate the utility of discrete-event simulation to evaluate flexible partitioning between low- and high-acuity ED areas to identify the best operational strategy for subsequent implementation. A discrete-event simulation was used to model patient flow through a 50-bed, urban, teaching ED that handles 85,000 patient visits annually. The ED has historically allocated 10 beds to a fast track for low-acuity patients. We estimated the effect of a flex track policy, which involved switching up to 5 of these fast track beds to serving both low- and high-acuity patients, on patient waiting times. When the high-acuity beds were not at capacity, low-acuity patients were given priority access to flexible beds. Otherwise, high-acuity patients were given priority access to flexible beds. Wait times were estimated for patients by disposition and Emergency Severity Index score. A flex track policy using 3 flexible beds produced the lowest mean patient waiting time of 30.9 minutes (95% confidence interval [CI] 30.6 to 31.2 minutes). The typical fast track approach of rigidly separating high- and low-acuity beds produced a mean patient wait time of 40.6 minutes (95% CI 40.2 to 50.0 minutes), 31% higher than that of the 3-bed flex track. A completely flexible ED, in which all beds can accommodate any patient, produced mean wait times of 35.1 minutes (95% CI 34.8 to 35.4 minutes). The results from the 3-bed flex track scenario were robust, performing well across a range of scenarios involving higher and lower patient volumes and care durations. Using discrete-event simulation, we have shown that adding some flexibility into bed allocation between low and high acuity can provide substantial reductions in overall patient waiting and a more efficient ED. Copyright © 2014 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.
ED adds business center to wait area.
2007-10-01
Providing your patients with Internet access in the waiting area can do wonders for their attitudes and make them much more understanding of long wait times. What's more, it doesn't take a fortune to create a business center. The ED at Florida Hospital Celebration (FL) Health made a world of difference with just a couple of computers and a printer. Have your information technology staff set the computers up to preserve the privacy of your internal computer system, and block out offensive sites. Access to medical sites can help reinforce your patient education efforts.
Crowdsourced validation of a machine-learning classification system for autism and ADHD.
Duda, M; Haber, N; Daniels, J; Wall, D P
2017-05-16
Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) together affect >10% of the children in the United States, but considerable behavioral overlaps between the two disorders can often complicate differential diagnosis. Currently, there is no screening test designed to differentiate between the two disorders, and with waiting times from initial suspicion to diagnosis upwards of a year, methods to quickly and accurately assess risk for these and other developmental disorders are desperately needed. In a previous study, we found that four machine-learning algorithms were able to accurately (area under the curve (AUC)>0.96) distinguish ASD from ADHD using only a small subset of items from the Social Responsiveness Scale (SRS). Here, we expand upon our prior work by including a novel crowdsourced data set of responses to our predefined top 15 SRS-derived questions from parents of children with ASD (n=248) or ADHD (n=174) to improve our model's capability to generalize to new, 'real-world' data. By mixing these novel survey data with our initial archival sample (n=3417) and performing repeated cross-validation with subsampling, we created a classification algorithm that performs with AUC=0.89±0.01 using only 15 questions.
NASA Astrophysics Data System (ADS)
Liou, Cheng-Dar
2015-09-01
This study investigates an infinite capacity Markovian queue with a single unreliable service station, in which the customers may balk (do not enter) and renege (leave the queue after entering). The unreliable service station can be working breakdowns even if no customers are in the system. The matrix-analytic method is used to compute the steady-state probabilities for the number of customers, rate matrix and stability condition in the system. The single-objective model for cost and bi-objective model for cost and expected waiting time are derived in the system to fit in with practical applications. The particle swarm optimisation algorithm is implemented to find the optimal combinations of parameters in the pursuit of minimum cost. Two different approaches are used to identify the Pareto optimal set and compared: the epsilon-constraint method and non-dominate sorting genetic algorithm. Compared results allow using the traditional optimisation approach epsilon-constraint method, which is computationally faster and permits a direct sensitivity analysis of the solution under constraint or parameter perturbation. The Pareto front and non-dominated solutions set are obtained and illustrated. The decision makers can use these to improve their decision-making quality.
High capacity low delay packet broadcasting multiaccess schemes for satellite repeater systems
NASA Astrophysics Data System (ADS)
Bose, S. K.
1980-12-01
Demand assigned packet radio schemes using satellite repeaters can achieve high capacities but often exhibit relatively large delays under low traffic conditions when compared to random access. Several schemes which improve delay performance at low traffic but which have high capacity are presented and analyzed. These schemes allow random acess attempts by users, who are waiting for channel assignments. The performance of these are considered in the context of a multiple point communication system carrying fixed length messages between geographically distributed (ground) user terminals which are linked via a satellite repeater. Channel assignments are done following a BCC queueing discipline by a (ground) central controller on the basis of requests correctly received over a collision type access channel. In TBACR Scheme A, some of the forward message channels are set aside for random access transmissions; the rest are used in a demand assigned mode. Schemes B and C operate all their forward message channels in a demand assignment mode but, by means of appropriate algorithms for trailer channel selection, allow random access attempts on unassigned channels. The latter scheme also introduces framing and slotting of the time axis to implement a more efficient algorithm for trailer channel selection than the former.
Inter-regional competition and quality in hospital care.
Aiura, Hiroshi
2013-06-01
This study analyzes the effect of episode-of-care payment and patient choice on waiting time and the comprehensive quality of hospital care. The study assumes that two hospitals are located in two cities with different population sizes and compete with each other. We find that the comprehensive quality of hospital care as well as waiting time of both hospitals improve with an increase in payment per episode of care. However, we also find that the extent of these improvements differs according to the population size of the cities where the hospitals are located. Under the realistic assumptions that hospitals involve significant labor-intensive work, we find the improvements in comprehensive quality and waiting time in a hospital located in a small city to be greater than those in a hospital located in a large city. The result implies that regional disparity in the quality of hospital care decreases with an increase in payment per episode of care.
Motion of kinesin in a viscoelastic medium
NASA Astrophysics Data System (ADS)
Knoops, Gert; Vanderzande, Carlo
2018-05-01
Kinesin is a molecular motor that transports cargo along microtubules. The results of many in vitro experiments on kinesin-1 are described by kinetic models in which one transition corresponds to the forward motion and subsequent binding of the tethered motor head. We argue that in a viscoelastic medium like the cytosol of a cell this step is not Markov and has to be described by a nonexponential waiting time distribution. We introduce a semi-Markov kinetic model for kinesin that takes this effect into account. We calculate, for arbitrary waiting time distributions, the moment generating function of the number of steps made, and determine from this the average velocity and the diffusion constant of the motor. We illustrate our results for the case of a waiting time distribution that is Weibull. We find that for realistic parameter values, viscoelasticity decreases the velocity and the diffusion constant, but increases the randomness (or Fano factor).
Chiappini, Elena; Camaioni, Angelo; Benazzo, Marco; Biondi, Andrea; Bottero, Sergio; De Masi, Salvatore; Di Mauro, Giuseppe; Doria, Mattia; Esposito, Susanna; Felisati, Giovanni; Felisati, Dino; Festini, Filippo; Gaini, Renato Maria; Galli, Luisa; Gambini, Claudio; Gianelli, Umberto; Landi, Massimo; Lucioni, Marco; Mansi, Nicola; Mazzantini, Rachele; Marchisio, Paola; Marseglia, Gian Luigi; Miniello, Vito Leonardo; Nicola, Marta; Novelli, Andrea; Paulli, Marco; Picca, Marina; Pillon, Marta; Pisani, Paolo; Pipolo, Carlotta; Principi, Nicola; Sardi, Iacopo; Succo, Giovanni; Tomà, Paolo; Tortoli, Enrico; Tucci, Filippo; Varricchio, Attilio; de Martino, Maurizio; Italian Guideline Panel For Management Of Cervical Lymphadenopathy In Children
2015-01-01
Cervical lymphadenopathy is a common disorder in children due to a wide spectrum of disorders. On the basis of a complete history and physical examination, paediatricians have to select, among the vast majority of children with a benign self-limiting condition, those at risk for other, more complex, diseases requiring laboratory tests, imaging and, finally, tissue sampling. At the same time, they should avoid expensive and invasive examinations when unnecessary. The Italian Society of Preventive and Social Pediatrics, jointly with the Italian Society of Pediatric Infectious Diseases, the Italian Society of Pediatric Otorhinolaryngology, and other Scientific Societies, issued a National Consensus document, based on the most recent literature findings, including an algorithm for the management of cervical lymphadenopathy in children. The Consensus Conference method was used, following the Italian National Plan Guidelines. Relevant publications in English were identified through a systematic review of MEDLINE and the Cochrane Database of Systematic Reviews from their inception through March 21, 2014. Basing on literature results, an algorithm was developed, including several possible clinical scenarios. Situations requiring a watchful waiting strategy, those requiring an empiric antibiotic therapy, and those necessitating a prompt diagnostic workup, considering the risk for a severe underling disease, have been identified. The present algorithm is a practice tool for the management of pediatric cervical lymphadenopathy in the hospital and the ambulatory settings. A multidisciplinary approach is paramount. Further studies are required for its validation in the clinical field.
Estimating Arrhenius parameters using temperature programmed molecular dynamics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Imandi, Venkataramana; Chatterjee, Abhijit, E-mail: abhijit@che.iitb.ac.in
2016-07-21
Kinetic rates at different temperatures and the associated Arrhenius parameters, whenever Arrhenius law is obeyed, are efficiently estimated by applying maximum likelihood analysis to waiting times collected using the temperature programmed molecular dynamics method. When transitions involving many activated pathways are available in the dataset, their rates may be calculated using the same collection of waiting times. Arrhenius behaviour is ascertained by comparing rates at the sampled temperatures with ones from the Arrhenius expression. Three prototype systems with corrugated energy landscapes, namely, solvated alanine dipeptide, diffusion at the metal-solvent interphase, and lithium diffusion in silicon, are studied to highlight variousmore » aspects of the method. The method becomes particularly appealing when the Arrhenius parameters can be used to find rates at low temperatures where transitions are rare. Systematic coarse-graining of states can further extend the time scales accessible to the method. Good estimates for the rate parameters are obtained with 500-1000 waiting times.« less
Improving queuing service at McDonald's
NASA Astrophysics Data System (ADS)
Koh, Hock Lye; Teh, Su Yean; Wong, Chin Keat; Lim, Hooi Kie; Migin, Melissa W.
2014-07-01
Fast food restaurants are popular among price-sensitive youths and working adults who value the conducive environment and convenient services. McDonald's chains of restaurants promote their sales during lunch hours by offering package meals which are perceived to be inexpensive. These promotional lunch meals attract good response, resulting in occasional long queues and inconvenient waiting times. A study is conducted to monitor the distribution of waiting time, queue length, customer arrival and departure patterns at a McDonald's restaurant located in Kuala Lumpur. A customer survey is conducted to gauge customers' satisfaction regarding waiting time and queue length. An android app named Que is developed to perform onsite queuing analysis and report key performance indices. The queuing theory in Que is based upon the concept of Poisson distribution. In this paper, Que is utilized to perform queuing analysis at this McDonald's restaurant with the aim of improving customer service, with particular reference to reducing queuing time and shortening queue length. Some results will be presented.
Pötschger, Ulrike; Heinzl, Harald; Valsecchi, Maria Grazia; Mittlböck, Martina
2018-01-19
Investigating the impact of a time-dependent intervention on the probability of long-term survival is statistically challenging. A typical example is stem-cell transplantation performed after successful donor identification from registered donors. Here, a suggested simple analysis based on the exogenous donor availability status according to registered donors would allow the estimation and comparison of survival probabilities. As donor search is usually ceased after a patient's event, donor availability status is incompletely observed, so that this simple comparison is not possible and the waiting time to donor identification needs to be addressed in the analysis to avoid bias. It is methodologically unclear, how to directly address cumulative long-term treatment effects without relying on proportional hazards while avoiding waiting time bias. The pseudo-value regression technique is able to handle the first two issues; a novel generalisation of this technique also avoids waiting time bias. Inverse-probability-of-censoring weighting is used to account for the partly unobserved exogenous covariate donor availability. Simulation studies demonstrate unbiasedness and satisfying coverage probabilities of the new method. A real data example demonstrates that study results based on generalised pseudo-values have a clear medical interpretation which supports the clinical decision making process. The proposed generalisation of the pseudo-value regression technique enables to compare survival probabilities between two independent groups where group membership becomes known over time and remains partly unknown. Hence, cumulative long-term treatment effects are directly addressed without relying on proportional hazards while avoiding waiting time bias.
Improvement of emergency department patient flow using lean thinking.
Sánchez, Miquel; Suárez, Montse; Asenjo, María; Bragulat, Ernest
2018-05-01
To apply lean thinking in triage acuity level-3 patients in order to improve emergency department (ED) throughtput and waiting time. A prospective interventional study. An ED of a tertiary care hospital. Triage acuity level-3 patients. To apply lean techniques such as value stream mapping, workplace organization, reduction of wastes and standardization by the frontline staff. Two periods were compared: (i) pre-lean: April-September, 2015; and (ii) post-lean: April-September, 2016. Variables included: median process time (time from beginning of nurse preparation to the end of nurse finalization after doctor disposition) of both discharged and transferred to observation patients; median length of stay; median waiting time; left without being seen, 72-h revisit and mortality rates, and daily number of visits. There was no additional staff or bed after lean implementation. Despite an increment in the daily number of visits (+8.3%, P < 0.001), significant reductions in process time of discharged (182 vs 160 min, P < 0.001) and transferred to observation (186 vs 176 min, P < 0.001) patients, in length of stay (389 vs 329 min, P < 0.001), and in waiting time (71 vs 48 min, P < 0.001) were achieved after lean implementation. No significant differences were registered in left without being seen rate (5.23% vs 4.95%), 72-h revisit rate (3.41% vs 3.93%), and mortality rate (0.23% vs 0.15%). Lean thinking is a methodology that can improve triage acuity level-3 patient flow in the ED, resulting in better throughput along with reduced waiting time.
Graph transformation method for calculating waiting times in Markov chains.
Trygubenko, Semen A; Wales, David J
2006-06-21
We describe an exact approach for calculating transition probabilities and waiting times in finite-state discrete-time Markov processes. All the states and the rules for transitions between them must be known in advance. We can then calculate averages over a given ensemble of paths for both additive and multiplicative properties in a nonstochastic and noniterative fashion. In particular, we can calculate the mean first-passage time between arbitrary groups of stationary points for discrete path sampling databases, and hence extract phenomenological rate constants. We present a number of examples to demonstrate the efficiency and robustness of this approach.
Wilson, Anna C.; Lengua, Liliana J.; Tininenko, Jennifer; Taylor, Adam; Trancik, Anika
2009-01-01
This longitudinal study utilized a community sample of children (N=91, 45% female, 8–11 years at time 1) to investigate physiological responses (heart rate reactivity [HRR] and electrodermal responding [EDR]) during delay of gratification in relation to emotionality, self-regulation, and adjustment problems. Cluster analyses identified three profiles among children who successfully delayed: children who waited easily with low EDR and moderate HRR, children who had difficulty waiting with high EDR and moderate HRR, and children who had difficulty waiting with low EDR and low HRR. The 3 clusters and children who did not wait were compared. Children with low EDR-low HRR had the lowest self-regulation, and like the no-wait group, demonstrated the greatest baseline adjustment problems. The high EDR-moderate HRR group demonstrated highest self-regulation and increases in depression across one year. Distinct profiles among children in delay contexts point to children who are over- and under-regulated with implications for adjustment problems. PMID:20046898
Terris, J; Leman, P; O'Connor, N; Wood, R
2004-09-01
To assess whether initial patient consult by senior clinicians reduces numbers of patients waiting to be seen as an indirect measure of waiting time throughout the emergency department (ED). An emergency medicine consultant and a senior ED nurse (G or F grade), known as the IMPACT team, staffed the triage area for four periods of four hours per week, Monday to Friday between 9 am to 5 pm for three months between December 2001 and February 2002 when staffing levels permitted. Patients normally triaged by a nurse in this area instead had an early consultation with the IMPACT team. Data were collected prospectively on all patients seen by the IMPACT team. The number of patients waiting to be seen (for triage, in majors and in minors) was assessed every two hours during the IMPACT sessions and at corresponding times when no IMPACT team was operational. There was an overall reduction in the number of patients waiting to be seen in the department from 18.3 to 5.5 (p<0.0001) at formal two hourly assessments. The largest difference was seen in minors. Of the patients seen at triage by the IMPACT team, 48.9% were discharged home immediately after assessment and treatment. With the IMPACT team present, no patient waited more than four hours for initial clinical consult. By using a senior clinical team for initial patient consultation, the numbers of patients waiting fell dramatically throughout the ED. Many patients can be effectively treated and discharged after initial consult by the IMPACT team.