Investigating effective maintenance policies for urban networks of residential cities by using optimum and sensitivity analyses

2020 ◽  
Vol 47 (6) ◽  
pp. 691-703
Author(s):  
Ahmed Salah Mohamed ◽  
Talaat Ali Abdel-Wahed ◽  
Ayman Mahmoud Othman
Keyword(s):  
Preventive Treatment ◽  
Cost Effective ◽  
Planning Horizon ◽  
Sensitivity Analyses ◽  
Optimal Time ◽  
Rational Solutions ◽  
Urban Network ◽  
Urban Networks ◽  
Rural And Urban ◽  
Maintenance Policies

Rural and urban networks have been rapidly expanding over time, so there is a rising demand for more optimum maintenance policies (MPs). The low traffic weights on the urban network of a residential city makes the appearance and density of load-associated distresses rare. This encourages the city’s transportation agency to depend on limited treatment choices and the subjective judgement of the agency’s engineers in managing maintenance and rehabilitation (M&R) activities. The engineers’ judgement reflects their extensive field experience and is usually used in this type of city rather than generating optimal computerized solutions. The present study proposes two alternative MPs that are more objective than the policy that depends on engineers’ judgement. One of the proposed alternative policies allows one M&R action along the planning horizon and the other allows multiple M&R actions. The optimum analysis showed that the preventive treatment is the optimal action for more than 50% of the network segments, which means that it plays a vital and nonnegligible role in improving the effectiveness of the M&R activities. Moreover, the sensitivity of the generated M&R plans to the initial performance of the pavement, traffic volume, and the objectives weights is investigated to determine the optimal time, suitable action, maintenance need, and optimal objective weights. The sensitivity analysis showed that varying objective weights leads to different optimal and rational solutions and the most cost-effective solution is not achieved at equal weights for objectives.

Cost-effectiveness analysis in patients with an unruptured cerebral aneurysm treated with observation or surgery

2021 ◽  
pp. 1-9
Author(s):  
Charlotte Dandurand ◽  
Lily Zhou ◽  
Swetha Prakash ◽  
Gary Redekop ◽  
Peter Gooderham ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Endovascular Treatment ◽  
Conservative Management ◽  
Preventive Treatment ◽  
Cost Effective ◽  
Sensitivity Analyses ◽  
Unruptured Intracranial Aneurysms ◽  
Life Years ◽  
Risk Of Rupture ◽  
Tertiary Center

OBJECTIVE The main goal of preventive treatment of unruptured intracranial aneurysms (UIAs) is to avoid the morbidity and mortality associated with aneurysmal subarachnoid hemorrhage. A comparison between the conservative approach and the surgical approach combining endovascular treatment and microsurgical clipping is currently lacking. This study aimed to conduct an updated evaluation of cost-effectiveness comparing the two approaches in patients with UIA. METHODS A decision tree with a Markov model was developed. Quality-adjusted life-years (QALYs) associated with living with UIA before and after treatment were prospectively collected from a cohort of patients with UIA at a tertiary center. Other inputs were obtained from published literature. Using Monte Carlo simulation for patients aged 55, 65, and 75 years, the authors modeled the conservative management in comparison with preventive treatment. Different proportions of endovascular and microsurgical treatment were modeled to reflect existing practice variations between treatment centers. Outcomes were assessed in terms of QALYs. Sensitivity analyses to assess the model’s robustness and completed threshold analyses to examine the influence of input parameters were performed. RESULTS Preventive treatment of UIAs consistently led to higher utility. Models using a higher proportion of endovascular therapy were more cost-effective. Models with older cohorts were less cost-effective than those with younger cohorts. Treatment was cost-effective (willingness to pay < 100,000 USD/QALY) if the annual rupture risk exceeded a threshold between 0.8% and 1.9% in various models based on the proportion of endovascular treatment and cohort age. A higher proportion of endovascular treatments and younger age lowered this threshold, making the treatment of aneurysms with a lower risk of rupture more cost-effective. CONCLUSIONS Preventive treatment of aneurysms led to higher utility compared with conservative management. Models with a higher proportion of endovascular treatment and younger patient age were most cost-effective.

Urban network of China from the perspective of population mobility: Three-dimensional co-occurrence of nodes and links

2021 ◽  
pp. 0308518X2199781
Author(s):  
Xinyue Luo ◽  
Mingxing Chen
Keyword(s):  
Three Dimensional ◽  
Geographical Distance ◽  
Two Dimensional ◽  
Population Mobility ◽  
Urban Network ◽  
Urban Networks ◽  
Low Level ◽  
Medium Level ◽  
High Level ◽  
External Connections

The nodes and links in urban networks are usually presented in a two-dimensional(2D) view. The co-occurrence of nodes and links can also be realized from a three-dimensional(3D) perspective to make the characteristics of urban network more intuitively revealed. Our result shows that the external connections of high-level cities are mainly affected by the level of cities(nodes) and less affected by geographical distance, while medium-level cities are affected by the interaction of the level of cities(nodes) and geographical distance. The external connections of low-level cities are greatly restricted by geographical distance.

scholarly journals Cost-effectiveness analysis of ranibizumab for retinal vein occlusion patients in China from the societal perspective

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Weiyi Ni ◽  
Jia Liu ◽  
Yawen Jiang ◽  
Jing Wu
Keyword(s):  
Cost Effectiveness ◽  
Retinal Vein Occlusion ◽  
Societal Perspective ◽  
Laser Photocoagulation ◽  
Cost Effective ◽  
Sensitivity Analyses ◽  
Gdp Per Capita ◽  
Base Case ◽  
Vein Occlusion ◽  
Per Capita

Abstract Background Clinical trials in China have demonstrated that ranibizumab can improve the clinical outcomes of branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO). However, no economic evaluation of ranibizumab has been conducted among Chinese patient population. Methods To provide insights into the economic profile of ranibizumab among Chinese RVO population, a Markov state-transition model was used to predict the outcomes of ranibizumab comparing to laser photocoagulation and observational-only care from the societal perspective. This model simulated changes in patient visuality, quality-adjusted of life years (QALY), medical costs, and direct non-medical costs of individuals with visual impairment due to BRVO or CRVO in lifetime. The base-case analysis used an annual discount rate of 5% for costs and benefits following the China Guidelines for Pharmacoeconomic Evaluations. Deterministic and probabilistic sensitivity analyses were performed to test the robustness of the model. Results The base-case incremental cost-effectiveness ratio (ICER) comparing ranibizumab to laser photocoagulation was ¥65,008/QALY among BRVO patients and was ¥65,815/QALY among CRVO patients, respectively. Comparing to the 2019 gross domestic product (GDP) per capita of ¥71,000, both two ICERs were far below the cost-effective threshold at three times of GDP per capita (¥213,000). The deterministic and probabilistic sensitivity analyses demonstrated the base-case results were robust in most of the simulation scenarios. Conclusion The current Markov model demonstrated that ranibizumab may be cost-effective compared with laser photocoagulation to treat BRVO and cost-effective compared to observation-only care to treat CRVO in China from the societal perspective.

Mapping urban networks through inter-firm service relationships: The case of China

Urban Studies ◽  
2017 ◽  
Vol 54 (16) ◽  
pp. 3639-3654 ◽  
Author(s):  
Fenghua Pan ◽  
Wenkai Bi ◽  
James Lenzer ◽  
Simon Zhao
Keyword(s):  
Initial Public Offering ◽  
Service Provision ◽  
Professional Services ◽  
Future Research ◽  
Law Firms ◽  
Economic Activities ◽  
Urban Network ◽  
Urban Networks ◽  
Producer Service ◽  
Public Offering

Literature on how cities get connected through networks of firms has been increasing in recent years. In particular, advanced producer service (APS) firms are being widely used to build intra-firm linkages to establish urban networks. In contrast to studies applying intra-firm networks, this study proposes an alternative strategy to build urban networks based on inter-firm service provision relationships during the process of initial public offering (IPO) in which APS firms – including securities, law firms and accounting firms – provide professional services for firms aiming to be publicly listed. Based on service provision connections between APS firms and their clients, this study provides fresh insights on urban networks in China. The results show that Beijing, Shenzhen and Shanghai strategically hold dominant positions within Chinese urban networks and they are the lead command and financial centres within the country. Particularly, Beijing has overwhelmingly more influence over other cities. The urban networks are embedded in China’s unique institutional context where market and state power together have shaped these networks. Since the urban network is built up based on real economic linkages, the findings might have further implications for policy-making and could contribute to ongoing debates regarding financial centres in China. It implies that connections between firms based on real economic activities can be an effective way to construct urban networks in future research.

scholarly journals Modeling the Costs of Hospital-Acquired Infections in New Zealand

2003 ◽  
Vol 24 (3) ◽  
pp. 214-223 ◽  
Author(s):  
Nicholas Graves ◽  
Tanya M. Nicholls ◽  
Arthur J. Morris
Keyword(s):  
New Zealand ◽  
Economic Cost ◽  
Cost Effective ◽  
Sensitivity Analyses ◽  
Primary Data ◽  
Health Board ◽  
District Health ◽  
Hospital Acquired Infections ◽  
Input Variables ◽  
Hospital Acquired

AbstractObjective:To model the economic costs of hospital-acquired infections (HAIs) in New Zealand, by type of HAI.Design:Monte Carlo simulation model.Setting:Auckland District Health Board Hospitals (DHBH), the largest publicly funded hospital group in New Zealand supplying secondary and tertiary services. Costs are also estimated for predicted HAIs in admissions to all hospitals in New Zealand.Patients:All adults admitted to general medical and general surgical services.Method:Data on the number of cases of HAI were combined with data on the estimated prolongation of hospital stay due to HAI to produce an estimate of the number of bed days attributable to HAI. A cost per bed day value was applied to provide an estimate of the economic cost. Costs were estimated for predicted infections of the urinary tract, surgical wounds, the lower and upper respiratory tracts, the bloodstream, and other sites, and for cases of multiple sites of infection. Sensitivity analyses were undertaken for input variables.Results:The estimated costs of predicted HAIs in medical and surgical admissions to Auckland DHBH were $10.12 (US $4.56) million and $8.64 (US $3.90) million, respectively. They were $51.35 (US $23.16) million and $85.26 (US $38.47) million, respectively, for medical and surgical admissions to all hospitals in New Zealand.Conclusions:The method used produces results that are less precise than those of a specifically designed study using primary data collection, but has been applied at a lower cost. The estimated cost of HAIs is substantial, but only a proportion of infections can be avoided. Further work is required to identify the most cost-effective strategies for the prevention of HAI.

Ixazomib (IXA), carfilzomib (CAR), elotuzumab (ELO) or daratumumab (DAR) with lenalidomide and dexamethasone (LEN+DEX) versus LEN+DEX only in relapsed/refractory multiple myeloma (R/R MM): A comparative cost-effectiveness analysis.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 8043-8043
Author(s):  
Mavis Obeng-Kusi ◽  
Daniel Arku ◽  
Neda Alrawashdh ◽  
Briana Choi ◽  
Nimer S. Alkhatib ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Cost Effective ◽  
Cost Utility ◽  
Cost Effectiveness Analysis ◽  
The Other ◽  
Sensitivity Analyses ◽  
Treatment Comparison ◽  
Comparative Cost ◽  
Effectiveness Analysis ◽  
Life Years

8043 Background: IXA, CAR, ELO and DARin combination with LEN+DEXhave been found superior in efficacy compared to LEN+DEX in the management of R/R MM. Applying indirect treatment comparisons from a network meta-analysis (NMA), this economic evaluation aimed to estimate the comparative cost-effectiveness and cost-utility of these four triplet regimens in terms of progression-free survival (PFS). Methods: In the absence of direct treatment comparison from a single clinical trial, NMA was used to indirectly estimate the comparative PFS benefit of each regimen. A 2-state Markov model simulating the health outcomes and costs was used to evaluate PFS life years (LY) and quality-adjusted life years (QALY) with the triplet regimens over LEN+DEX and expressed as the incremental cost-effectiveness (ICER) and cost-utility ratios (ICUR). Probability sensitivity analyses were conducted to assess the influence of parameter uncertainty on the model. Results: The NMA revealed that DAR+LEN+DEX was superior to the other triplet therapies, which did not differ statistically amongst them. As detailed in the Table, in our cost-effectiveness analysis, all 4 triplet regimens were associated with increased PFSLY and PFSQALY gained (g) over LEN+DEX at an additional cost. DAR+LEN+DEX emerged the most cost-effective with ICER and ICUR of $667,652/PFSLYg and $813,322/PFSQALYg, respectively. The highest probability of cost-effectiveness occurred at a willingness-to-pay threshold of $1,040,000/QALYg. Conclusions: Our economic analysis shows that all the triplet regimens were more expensive than LEN +DEX only but were also more effective with respect to PFSLY and PFSQALY gained. Relative to the other regimens, the daratumumab regimen was the most cost-effective.[Table: see text]

Abstract 15595: Missed Targets: United States Trends in Hypertension Prevalence, Control, and Treatment 2005-2018

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Rahul Aggarwal ◽  
Nicholas Chiu ◽  
Rishi Wadhera ◽  
Changyu Shen ◽  
Robert W Yeh ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Temporal Trends ◽  
Cost Effective ◽  
Pressure Control ◽  
Healthy People ◽  
Sensitivity Analyses ◽  
Base Case ◽  
Improve Blood Pressure Control ◽  
Hypertension Prevalence ◽  
And Control

Introduction: Hypertension is a major risk factor for cardiovascular disease. The US government, through the Healthy People Initiative 2020, set targets to improve hypertension prevalence and treatment rates in US adults by a relative 10% from 2005 to 2020, and increase control rates by a relative 40%. We examined US progress towards this goal from 2005-2018. Methods: We analyzed data from 38,876 non-pregnant US adults from the NHANES 2005-2018 surveys to determine nationally representative estimates of hypertension prevalence, treatment rates, and control. Temporal trends in hypertension prevalence, treatment, and control were assessed using weighted linear regression after age adjustment to the 2000 US census (per the Healthy People Initiative approach). In the base case, we defined hypertension as blood pressure >140/90 or on an antihypertensive; we used the ACC/AHA definition of blood pressure >130/80 in sensitivity analyses. Results: In 2017-2018, 34.3% (±1.7) of US adults had hypertension, of these 69.7% (±1.5) were on treatment, and 43.7% (±1.6) were controlled. After age-adjustment, no statistically significant changes in hypertension prevalence, treatment rates, or control were observed from 2005-2018 (p for trend 0.91, ,0.98, 0.66, Figure 1). In sensitivity analyses, applying the ACC/AHA definition increased the estimated prevalence of hypertension during the period, but trends in prevalence remained unchanged. Conclusions: There has been no material progress in reducing the prevalence of hypertension or improving rates of treatment and control from 2005 to 2018. As planning is underway for Healthy People Initiative 2030, setting of hypertension targets must be accompanied with investments in cost-effective, scalable programs to improve blood pressure control nationwide, with a focus on high-risk populations.

COST-UTILITY ANALYSIS OF MULTIPLE SCLEROSIS TREATMENT IN THAILAND

2018 ◽  
Vol 34 (6) ◽  
pp. 584-592
Author(s):  
Chalakorn Chanatittarat ◽  
Usa Chaikledkaew ◽  
Naraporn Prayoonwiwat ◽  
Sasitorn Siritho ◽  
Pakamas Pasogpakdee ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Cost Effective ◽  
Best Supportive Care ◽  
Quality Adjusted Life Year ◽  
Cost Utility ◽  
Outcome Data ◽  
Essential Medicines ◽  
Sensitivity Analyses ◽  
Lifetime Horizon ◽  
Cost Effective Treatment

Objectives:Although interferon beta-1a (IFNß−1a), 1b (IFNß−1b), and fingolimod have been approved as multiple sclerosis (MS) treatments, they have not yet been included on the National List of Essential Medicines (NLEM) formulary in Thailand. This study aimed to evaluate the cost-utility of MS treatments compared with best supportive care (BSC) based on a societal perspective in Thailand.Methods:A Markov model with cost and health outcomes over a lifetime horizon with a 1-month cycle length was conducted for relapsing–remitting MS (RRMS) patients. Cost and outcome data were obtained from published studies, collected from major MS clinics in Thailand and a discount rate of 3 percent was applied. The incremental cost-effectiveness ratio (ICER) was calculated and univariate and probabilistic sensitivity analyses were performed.Results:When compared with BSC, the ICERs for patients with RRMS aged 35 years receiving fingolimod, IFNβ−1b, and IFNβ−1a were 33,000, 12,000, and 42,000 US dollars (USD) per quality-adjusted life-year (QALY) gained, respectively. At the Thai societal willingness to pay (WTP) threshold of USD 4,500 per QALY gained, BSC had the highest probability of being cost-effective (49 percent), whereas IFNβ−1b and fingolimod treatments showed lower chance being cost-effective at 25 percent and 18 percent, respectively.Conclusions:Compared with fingolimod and interferon treatments, BSC remains to be the most cost-effective treatment for RRMS in Thailand based on a WTP threshold of USD 4,500 per QALY gained. The results do not support the inclusion of fingolimod or interferon in the NLEM for the treatment of RRMS unless their prices are decreased or special schema arranged.

Anaerobic digestion for sustainable development: a natural approach

2002 ◽  
Vol 45 (10) ◽  
pp. 321-328 ◽  
Author(s):  
H.J. Gijzen
Keyword(s):  
Industrial Wastewater ◽  
Systems Approach ◽  
Cost Effective ◽  
Anaerobic Treatment ◽  
High Rate ◽  
Natural Ecosystems ◽  
Natural Systems ◽  
Anaerobic Reactors ◽  
Rural And Urban ◽  
Pre Treatment

After the discovery of methane gas by Alessandro Volta in 1776, it took about 100 years before anaerobic processes for the treatment of wastewater and sludges were introduced. The development of high rate anaerobic digesters for the treatment of sewage and industrial wastewater took until the nineteen-seventies and for solid waste even till the nineteen-eighties. All digesters have in common that they apply natural anaerobic consortia of microorganisms for degradation and transformation processes. In view of this, it could be rewarding to evaluate the efficiency of natural ecosystems for their possible application. Examples of high rate anaerobic natural systems include the forestomach of ruminants and the hindgut of certain insects, such as termites and cockroaches. These “natural reactors” exhibit volumetric methane production rates as high as 35 l/l.d. The development of anaerobic reactors based on such natural anaerobic systems could produce eco-technologies for the effective management of a wide variety of solid wastes and industrial wastewater. Important limitations of anaerobic treatment of domestic sewage relate to the absence of nutrient and pathogen removal. A combination of anaerobic pre-treatment followed by photosynthetic post-treatment is proposed for the effective recovery of energy and nutrients from sewage. This eco-technology approach is based on the recognition that the main nutrient assimilating capacity is housed in photosynthetic plants. The proposed anaerobic-photosynthetic process is energy efficient, cost effective and applicable under a wide variety of rural and urban conditions. In conclusion: a natural systems approach towards waste management could generate affordable eco-technologies for effective treatment and resource recovery.

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