Size Of Catchment Area Research Articles

Quantifying the effects of Singapore’s street configurations on people’s activity spaces

Although it is generally accepted that street configurations may influence people’s intra-urban travel, capturing the exact nature of that influence remains challenging. We frame this challenge as one of operationalization and measurement and attempt to quantify and analyze the impact of street configurations more precisely. We draw on geographic data science tools to suggest that street configurations may be captured using catchment area polygons. To illustrate our approach, we derive these polygons for every building in Singapore and show that catchment area sizes spatially cluster, thus acting as proxies for street configurations. Using a spatial error model, we demonstrate that these catchment area sizes partially explain people’s intra-urban travel, conceptualized as their activity spaces. That is, as street configurations lead to larger catchment areas, people’s activity spaces tend to shrink. We show that the explanatory power of catchment area sizes is distinct from, albeit correlated with, other built environment variables (such as amenity density and land use diversity) typically used to explain people’s travel. We conclude by considering the potential of our approach in broader urban geographical research agendas drawing on street configurations and other morphological influences in the study of socio-spatial processes.

Effects of buffer size on associations between the built environment and metro ridership: A machine learning-based sensitive analysis

Uncertainty in the relevant buffer size of metro station catchment areas may drive inconsistencies in the findings on the built environment and metro ridership. Although previous studies estimate the effect of this uncertainty, the results are far from definitive. By utilizing finer-grained big data and non-parametric machine learning approaches, this study conducted a sensitivity analysis defining built environment factors within four radial buffer sizes: 300 m, 600 m, 800 m, and 1000 m on associations with metro ridership. The results suggest that: (1) different buffer sizes have little influence on the ordinary least-squares model's predictive power, but significant influence on the machine learning model; (2) the use of a 600 m buffer size around the transit station demonstrates the best model fit and variation explanation compared to others; (3) findings on the relative importance, ranks, and nonlinear associations with metro ridership can be impacted as the choice of geographic delineation of buffer sizes deviate from the true relevant geographic context of built environment variables. The results assist planners in setting a benchmark for metro catchment areas for station-area planning and demand forecasting, more importantly, the findings highlight the importance of meticulously selecting the analytical spatial unit for area-based variables, especially when utilizing non-parametric machine learning approaches in research.

The Breast-Imaging Operations, Practices and Systems Inventory: A framework to examine mammography facility effects on screening in rural communities.

Develop and test a measurement framework of mammogram facility resources, policies, and practices in Appalachia. Survey items describing 7 domains of imaging facility qualities were developed and tested in the Appalachian regions of Kentucky, Ohio, Pennsylvania, Virginia, and West Virginia. Medicare claims data (2016-2018) were obtained on catchment area mammogram services. Construct validity was examined from associations with facility affiliation, community characteristics, mammogram screening uptake, and market reach. Analyses were performed with t-tests and ANOVA. A total of 192 (of 377) sites completed the survey. Five factors were initially selected in exploratory factor analysis (FA) and refined in confirmatory FA: capacity, outreach & marketing, operational support, radiology review (NNFI = .94, GFI = 0.93), and diagnostic services (NNFI = 1.00, GFI = 0.99). Imaging capacity and diagnostic services were associated with screening uptake, with capacity strongly associated with catchment area demographic and economic characteristics. Imaging facilities in economically affluent versus poorer areas belong to larger health systems and have significantly more resources (P < .001). Facilities in economically distressed locations in Appalachia rely more heavily on outreach activities (P < .001). Higher facility capacity was significantly associated (P < .05) with larger catchment area size (median split: 48.5vs 51.6), mammogram market share (47.4vs 52.7), and screening uptake (47.6vs 52.4). A set of 18 items assessing breast imaging services and facility characteristics was obtained, representing policies and practices related to a facility's catchment area size, market share, and mammogram screening uptake.

Evaluation of Kovacs 1988 Regional Maximum Flood Method

Estimation of design flood peaks is required for the design and evaluation of hydraulic structures. Methodologies developed between the 1960s and the late 1980s, such as the Regional Maximum Flood (RMF), are used to estimate extreme flood peaks in South Africa. The RMF method uses envelope curves to estimate the maximum flood that can be expected in a specific region in South Africa and neighbouring countries, and represents an indicative upper flood limit for other flood estimation methods. The method developed by Kovacs for South Africa was last updated in 1988. Using more than 30 years of additional data for analysis, this paper highlights the RMF's perceived shortcomings. In two RMF regions, updated observed flood peaks exceeded the existing envelope curves. In 78% of the catchment areas of the evaluated stations, the station RMF values were at least 50% more than the observed maximum flood peak. When the different parameters from the Kovacs 1988 and present DWS (Department of Water and Sanitation) datasets were compared, 98% of the evaluated stations had different flood peaks recorded/reported, while 33% of the stations logged different catchment area sizes. Kovacs 1988 ratios used to estimate flood peaks at different probabilities of occurrence, using the RMF, were found to generally over-estimate expected flood peaks. It is concluded that the 1988 RMF method needs to be updated to still provide relevant guidance.

Association between service readiness and PMTCT cascade effectiveness: a 2018 cross-sectional analysis from Manica province, Mozambique

BackgroundDespite high coverage of maternal and child health services in Mozambique, prevention of mother-to-child transmission of HIV (PMTCT) cascade outcomes remain sub-optimal. Delivery effectiveness is modified by health system preparedness. Identifying modifiable factors that impact quality of care and service uptake can inform strategies to improve the effectiveness of PMTCT programs. We estimated associations between facility-level modifiable health system readiness measures and three PMTCT outcomes: Early infant diagnosis (polymerase chain reaction (PCR) before 8 weeks of life), PCR ever (before or after 8 weeks), and positive PCR test result.MethodsA 2018 cross-sectional, facility-level survey was conducted in a sample of 36 health facilities covering all 12 districts in Manica province, central Mozambique, as part of a baseline assessment for the SAIA-SCALE trial (NCT03425136). Data on HIV testing outcomes among 3,427 exposed infants were abstracted from at-risk child service registries. Nine health system readiness measures were included in the analysis. Logistic regressions were used to estimate associations between readiness measures and pediatric HIV testing outcomes. Odds ratios (OR) and 95% confidence intervals (95%CI) are reported.ResultsForty-eight percent of HIV-exposed infants had a PCR test within 8 weeks of life, 69% had a PCR test ever, and 6% tested positive. Staffing levels, glove stockouts, and distance to the reference laboratory were positively associated with early PCR (OR = 1.02 [95%CI: 1.01–1.02], OR = 1.73 [95%CI: 1.24–2.40] and OR = 1.01 [95%CI: 1.00–1.01], respectively) and ever PCR (OR = 1.02 [95%CI: 1.01–1.02], OR = 1.80 [95%CI: 1.26–2.58] and OR = 1.01 [95%CI: 1.00–1.01], respectively). Catchment area size and multiple NGOs supporting PMTCT services were associated with early PCR testing OR = 1.02 [95%CI: 1.01–1.03] and OR = 0.54 [95%CI: 0.30–0.97], respectively). Facility type, stockout of prophylactic antiretrovirals, the presence of quality improvement programs and mothers’ support groups in the health facility were not associated with PCR testing. No significant associations with positive HIV diagnosis were found.ConclusionSalient modifiable factors associated with HIV testing for exposed infants include staffing levels, NGO support, stockout of essential commodities and accessibility of reference laboratories. Our study provides insights into modifiable factors that could be targeted to improve PMTCT performance, particularly at small and rural facilities.

Hazard Assessment of Potential Large-Scale Landslides in the Watershed of the Chenyulan River

Taiwan’s mountains are steep, geologically dispersed, and their hillsides are over-utilized. Serious debris flow disasters are prone to happen whenever monsoons or typhoons bring a lot of rain. Typhoon Morakot’s large-scale landslide in 2009, which devastated half of Xiaolin Village and claimed around 500 lives, is one such instance. Large-scale landslides have the potential to seriously harm people, property, and the economy. Large-scale landslides were less frequent in the past, but they have recently increased in frequency. An important topic is how to avert disasters through efficient risk management. Eight influencing factors were chosen after multivariate analysis screening, including three terrestrial factors (total catchment area size, average catchment area slope, and total curvature), three material factors (stratum type, distance from fault, and average normalized-difference vegetation index prior to the event), and two trigger factors (maximum daily rainfall and maximum hourly rainfall). Our overall analysis’ accuracy rankings were as follows: neural network, 93.7%; logistic regression analysis, 92.2%; and discriminant analysis, 89%. The area under curve (AUC) values for the neural network (0.819), discriminant analysis (0.824), and logistic regression analysis (0.732) all demonstrated high discriminative abilities based on the receiver operating characteristic curve, indicating that all three of our models are adequate for this purpose. Large-scale debris flow disasters are more likely to happen when the catchment region’s total area, total curvature, and average slope are higher, according to a cluster study. These findings can help to decrease the effects of disasters of this kind by helping to create early warning systems.

Assessing patients’ acceptable and realised distances to determine accessibility standards for the size of catchment areas in outpatient care

Healthcare planning aims to ensure availability of care in a needs-based, evenly distributed and locally available manner. However, many planning mechanisms lack accessibility standards. To determine standards, catchment areas must be derived from health-related travel assessments and a population's distance acceptance for different medical specialisation levels.We estimated distance acceptance using representative cross-sectional survey data (n = 1.598). Moreover, we used utilization data covering 88% of the German population (2014/15) to calculate realised travel distances for six medical specialties (n = 676.255.605 cases). We specified a gravity-based distance decay function and estimated regression-based distance thresholds from both samples.Realised distances were mostly below 30 min (90% of cases) indicating appropriate mean accessibility. The 5% observed distance threshold was between 23.7 min for GPs and 47.6 min for dermatologists. Depending on medical speciality, distance acceptance was mainly determined by distance, age, activity level and town size for GP visits and by health and income for specialist care. 5% acceptance thresholds varied between 27.9 min to GPs for elderly patients and 51.6 min to orthopaedists for younger patients. Acceptable distances for 90% of the population were 6 (8) minutes to GPs (specialists). The variation of thresholds, which depended on socio-demographic and health variables and the population share that is fully accepting, illustrates that healthcare planners should move beyond averages to realise equal access for equal need.

Planning for Maternity Waiting Home Bed Capacity: Lessons from Rural Zambia.

Background:Maternity waiting homes (MWH) allow pregnant women to stay in a residential facility close to a health center while awaiting delivery. This approach can improve health outcomes for women and children. Health planners need to consider many factors in deciding the number of beds needed for an MWH.Objective:The objective of the study is to review experience in Zambia in planning and implementing MWHs, and consider lessons learned in determining optimal capacity.Methods:We conducted a study of 10 newly built MWH in Zambia over 12 months. For this case study analysis, data on beds, service volume, and catchment area population were examined, including women staying at the homes, bed occupancy, and average length of stay. We analyzed bed occupancy by location and health facility catchment area size, and categorized occupancy by month from very low to very high.Findings:Most study sites were rural, with 3 of the 10 study sites rural-remote. Four sites served small catchment areas (<9 000), 3 had medium (9 000–11 000), and 3 had large (>11 000) size populations. Annual occupancy was variable among the sites, ranging from 13% (a medium rural site) to 151% (a large rural-remote site). Occupancy higher than 100% was accommodated by repurposing the MWH postnatal beds and using extra mattresses. Most sites had between 26–69% annual occupancy, but monthly occupancy was highly variable for reasons that seem unrelated to catchment area size, rural or rural-remote location.Conclusion:Planning for MWH capacity is difficult due to high variability. Our analysis suggests planners should try to gather actual recent monthly birth data and estimate capacity using the highest expected utilization months, anticipating that facility-based deliveries may increase with introduction of a MWH. Further research is needed to document and share data on MWH operations, including utilization statistics like number of beds, mattresses, occupancy rates and average length of stay.

Abstract TMP32: Modeling Optimal Patient Transport In A Stroke Network Capable Of Telerobotic Endovascular Therapy

Introduction: Endovascular therapy (EVT) is the standard-of-care for large vessel occlusion stroke; yet, a substantial portion of the population lacks timely access to the treatment. Telerobotics has the potential to expand current stroke networks by offering remote EVT to more rural populations. Methods: We geospatially mapped all existing hospitals in California and then assessed hypothetical scenarios in which primary stroke centers between 50 and 100 miles from an existing EVT center offered remote EVT via robotics. Using an existing conditional probability model, we determined the transport scenarios (drip and ship, direct to robotic EVT center, or direct to conventional EVT center) resulting in best patient outcomes in diverse geographies across the state. Timing and the probability of receiving EVT (used as a surrogate for the probability of receiving successful reperfusion) were varied at robotic centers to assess impact on best predicted transport options. Results: 10 hospitals were converted to robotic EVT centers, resulting in enhanced patient access to timely EVT by routing patients in a rural catchment area of 113,063 km 2 directly to robotic EVT centers (figure). Slowing the door to arterial access time at the robotic centers by 30 minutes had a minor impact on optimized service arrangements (reducing the robotic catchment area to 110,555 km 2 ). However, decreasing the probability of receiving EVT at the robotic centers by 0.10 had a substantial impact, reducing the robotic EVT catchment area to 35,061 km 2 and nearly doubling the drip and ship catchment area. Discussion: Telerobotic EVT has the potential to enhance therapy for stroke patients outside of major urban centers. We found that the reduced probability of receiving EVT had a greater impact on the optimized size of robotic EVT center catchment areas compared to longer door to arterial access times. This modeling analysis can inform system planning for the potential advent of remote robotic EVT care.

P467 Therapeutic drug monitoring of biologics in Inflammatory Bowel Disease: Nordic survey on implementation and barriers in clinical practice

Abstract Background Therapeutic drug monitoring (TDM) is a useful tool to optimise biologic treatments of patients with inflammatory bowel disease (IBD). Albeit broadly recommended by gastrointestinal societies, it is, however, currently unknown how TDM has been adopted and is being used in everyday clinical practice. The aim of the study was to investigate how TDM has been taken up by physicians including barriers for implementation. Methods A web-based survey on TDM was distributed to all gastroenterology consultants in the Nordic countries via national gastroenterology- and IBD societies. Results Out of 377 physicians responding, 297 handled IBD patients on biologic therapies and were thus eligible for inclusion (NO 118 (40%), DK 86 (29%), SE 50 (17%), FI 33 (11%), IS 10 (3%)). The vast majority were consultant gastroenterologists (n=252, 85%), 152 (51%) were employed at university hospitals, 136 (46%) at community hospitals, and 9 (3%) in private practice. Overall, 257 (87%) used TDM during biologic therapies; 231 (90%) used reactive TDM and 163 (63%) proactive TDM. Common indications were to improve efficacy (70%), aid treatment decisions (62%), improve safety (36%), and improve cost-effectiveness (32%). Notably, Danish physicians used TDM to a significantly lesser extent than all others (58% vs 98%; odds ratio (OR) 0.03 [95%CI 0.01- 0.09], p&amp;lt;0.001); in particular outside the capital region (OR 0.15 [0.05–0.46], p=0.001). Reactive TDM was applied both at primary (74%) and secondary treatment failure (99%) and predominantly for TNF-inhibitors (90–98%) (vedolizumab 63%, ustekinumab 46%). Proactive TDM was used by 80% during maintenance therapy and 56% during induction, and mostly for TNF-inhibitors (79–97%) (vedolizumab 70%, ustekinumab 54%). Proactive TDM was more commonly used in NO, SE, and FI (p&amp;lt;0.001), and by physicians managing &amp;gt;10 IBD patients per week (OR 2.71 [1.34–5.48], p=0.005), but was not associated with employment at university hospital, size of hospital catchment area, or seniority. Main barriers to the use of TDM were lack of guidelines (51%), long response time from the laboratory (49%), lack of knowledge regarding how to use and interpret test results (42%), costs (38%), and currently available evidence (31%). Among physicians using TDM, only 66% reported awareness of TDM guidelines or recommendations. Conclusion TDM, and in particular reactive TDM of TNF-inhibitors, has been broadly adopted into clinical practice in the Nordic countries to improve efficacy and assist treatment decisions. Across the Nordic countries, IBD physicians call for improved test response times and, notably, TDM guidelines detailing indications for TDM and interpretation of test results.

Race-Ethnic Enrollment Disparities over 15 Years of Alliance/CALGB Acute Myeloid Leukemia Clinical Trials, Biobanks, and Correlative Science Protocols

IntroductionRace-ethnic disparities in clinical trial enrollment have the potential to bias findings, limit generalizability, misdirect drug development, and reduce equitable access to novel therapy. The degree to which such disparities exist within acute myeloid leukemia (AML) North American cooperative group trials, biobanks, and correlative studies remain unclear, as are the factors that influence biobank and correlative study participation among trial enrollees. In addition, the National Cancer Institute's (NCI) mandate for Comprehensive Cancer Centers (CCC) to designate catchment areas has not been explored as a mechanism through which AML enrollment disparities can be addressed.MethodsWe analyzed enrollment data from the 9 Alliance/CALGB AML treatment trials, 2 biobank protocols, and 2 correlative studies active from 1998-2013 and with published results. Trial enrollees could consent to biobank and/or correlative study participation. We compared participation rates of United States (US) enrollees for the mutually exclusive racial-ethnic groups of non-Hispanic (NH)-white, NH-Black, NH-Asian, NH-Native American, and Hispanic using X 2 testing, with NH-white as the comparator and reporting odds ratios (OR) and 95% confidence intervals (CI). Rates were adjusted by national incidence according to the Surveillance, Epidemiology, and End Results program and the US Census. Testing was repeated for the 55% of participants enrolled at 15 NCI CCCs recruiting ≥10 patients, where incidence was adjusted for catchment area size and demographics. Logistic regression models, clustered by trial, were performed to assess the following predictors for biobank and correlative study participation among trial enrollees: race-ethnicity (NH-white vs non-white), site type (CCC status), age (10-year increments), sex, neighborhood urbanity (urban vs rural) and poverty (<20% vs ≥20% below poverty line) by zip code, and distance from site (10-mile increments).ResultsThere were 3041 trial enrollees at US sites; participant characteristics and demographics by race-ethnicity are shown in Table 1. 93.9% of patients participated in a biobanking study and 60.0% in a correlative study. National incidence adjusted enrollment odds by race-ethnicity are shown in the Figure (top); NH-Black, NH-Asian, and Hispanic persons were enrolled at significantly lower rates than NH-whites; NH-Native American enrollment was significantly higher. Enrollment odds were even lower for NH-Black, NH-Asian, and Hispanic enrollees at CCC sites when adjusted by catchment area incidence (Figure; bottom). Among trial enrollees, there were no univariable predictors of biobank participation, however, male sex (OR 1.12; 95% CI 1.01, 1.37; p=0.04) and NH-white race-ethnicity (OR 1.33; 95% CI 1.12,1.57; p<0.001) were associated with correlative study participation. Multivariable models of correlative study participation, with predictors selected based on univariable significance, are shown in Table 2 for all trial enrollees and when restricted to biobank enrollees; in both cases, NH-white race predicted participation.ConclusionsAcross 15 years of AML cooperative group studies, there were several enrollment disparities by race-ethnicity, which were more pronounced at CCC sites. Over 90% of trial enrollees participated in biobanking, with no race-ethnic differences seen. However, correlative study participation among trial enrollees was higher for NH-whites. Taken together, these data suggest that efforts should focus on increasing trial and correlative study participant diversity-but not biobanking-within NCI-designated CCC catchment areas. Reasonable next steps include identifying key structural, provider, and patient-based barriers to trial and correlative study participation at CCC sites and developing inclusive, multilevel interventions to address them. [Display omitted] DisclosuresEisfeld: Karyopharm (spouse): Current Employment. Stock: Pfizer: Consultancy, Honoraria, Research Funding; amgen: Honoraria; agios: Honoraria; jazz: Honoraria; kura: Honoraria; kite: Honoraria; morphosys: Honoraria; servier: Honoraria; syndax: Consultancy, Honoraria; Pluristeem: Consultancy, Honoraria. Stone: AbbVie Inc, Actinium Pharmaceuticals Inc, Aprea Therapeutics, BerGenBio ASA, ElevateBio, Foghorn Therapeutics, GEMoaB, GlaxoSmithKline, Innate Pharma, Syndax Pharmaceuticals Inc, Syros Pharmaceuticals Inc, Takeda Oncology: Other: Advisory Committee; Agios Pharmaceuticals Inc, Novartis;: Research Funding; ACI Clinical, Syntrix Pharmaceuticals, Takeda Oncology: Other: Data Safety & Monitoring. DeAngelo: Abbvie: Research Funding; Blueprint: Research Funding; Takeda: Consultancy; Autolus: Consultancy; Forty-Seven: Consultancy; Incyte: Consultancy; Jazz: Consultancy; Novartis: Consultancy, Research Funding; Pfizer: Consultancy; Servier: Consultancy; Amgen: Consultancy; Agios: Consultancy; Glycomimetrics: Research Funding. Byrd: Newave: Membership on an entity's Board of Directors or advisory committees; Vincerx Pharmaceuticals: Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Novartis, Trillium, Astellas, AstraZeneca, Pharmacyclics, Syndax: Consultancy, Honoraria.

Towards Health Equality: Optimizing Hierarchical Healthcare Facilities towards Maximal Accessibility Equality in Shenzhen, China

Equal accessibility to healthcare services is essential to the achievement of health equality. Recent studies have made important progresses in leveraging GIS-based location–allocation models to optimize the equality of healthcare accessibility, but have overlooked the hierarchical nature of facilities. This study developed a hierarchical maximal accessibility equality model for optimizing hierarchical healthcare facilities. The model aims to maximize the equality of healthcare facilities, which is quantified as the variance of the accessibility to facilities at each level. It also accounts for different catchment area sizes of, and distance friction effects for hierarchical facilities. To make the optimization more realistic, it can also simultaneously consider both existing and new facilities that can be located anywhere. The model was operationalized in a case study of Shenzhen, China. Empirical results indicate that the optimal healthcare facility allocation based on the model provided more equal accessibility than the status quo. Compared to the current distribution, the accessibility equality of tertiary and secondary healthcare facilities in optimal solutions can be improved by 40% and 38%, respectively. Both newly added facilities and adjustments of existing facilities are needed to achieve equal healthcare accessibility. Furthermore, the optimization results are quite different for facilities at different levels, which highlights the feasibility and value of the proposed hierarchical maximal accessibility equality model. This study provides transferable methods for the equality-oriented optimization and planning of hierarchical facilities.

Assessing the Impacts of Hierarchical Healthcare System on the Accessibility and Spatial Equality of Healthcare Services in Shenzhen, China

The hierarchical healthcare system is widely considered to be a desirable mode of the delivery of healthcare services. It is expected that the establishment of a hierarchical healthcare system can help provide better and more equal healthcare accessibility. However, limited evidence has been provided on the impacts of a hierarchical healthcare system on healthcare accessibility. This study develops an improved Hierarchical two-step floating catchment area (2SFCA) method, which incorporates variable catchment area sizes, distance friction effects and utilization efficiency for facilities at different levels. Leveraging the Hierarchical 2SFCA method, various scenarios are set up to assess the accessibility impacts of a hierarchical healthcare system. The methods are applied in a case study of Shenzhen. The results reveal significant disparity and inequality in healthcare accessibility and also differences between various facility levels in Shenzhen. The overall healthcare accessibility and its equality can be significantly improved by fully utilizing existing facilities. It is also demonstrated that allocating additional supply to lower-level facilities can generate larger accessibility gains. Furthermore, allocating new supply to primary facilities would mitigate the inequality in healthcare accessibility, whereas inequality tends to be aggravated with new supply allocated to tertiary facilities. These impacts cannot be captured by traditional accessibility measures. This study demonstrates the pivotal role of primary facilities in the hierarchical healthcare system. It can contribute to the literature by providing transferable methods and procedures for measuring hierarchical healthcare accessibility and assessing accessibility impacts of a hierarchical healthcare system in developing countries.

Comparative accessibility of Chinese airports and high-speed railway stations: A high-resolution, yet scalable framework based on open data

Despite China's massive infrastructure expansions in airports and high-speed railway (HSR), accessibility to these infrastructures from the passenger's perspective has yet been clearly analyzed and compared. The main objectives of this study are: (1) to evaluate accessibility by travel time between a given population grid cell and the nearest airport/HSR station, by accounting for both motorized vehicles and public transport; and (2) to measure and visualize the size of catchment area of an airport or a HSR station. We automatize the computation of free-flow road travel times, as well as the public transit times (by bus, subway, light-rail, tram and railway), from grid cells to infrastructure elements, by using a scalable routing framework. The Chinese air transportation network and HSR network are used as case studies to elaborate and evaluate the efficiency of our proposed framework. We find that the HSR network for China is much better accessible for the population than airports. Furthermore, grid cells with a high population density are much better connected to the Chinese transportation networks than other grid cells. Our methodology is generic in that it can be applied on an even larger scale (whole planet) and with different points of interest. Our work can help provide decision support for airport competition, privatization, and regulation, and for policy makers in infrastructure investment, in particular potential market and the location of new infrastructure elements.

An adapted two-step floating catchment area method accounting for urban-rural differences in spatial access to pharmacies.

To adapt the two-step floating catchment area approach to account for urban-rural differences in pharmacy access in the United States. The urban-rural two-step floating catchment area method was described mathematically. To calculate urban-rural-two-step floating catchment area measure, census tracts and pharmacies within the study area (Southeastern Wisconsin) were classified as urban, suburban or rural, and then different catchment area sizes (2, 5 and 15 miles) were applied, based on the Centers for Medicare & Medicaid Services (CMS)' criteria for Medicare Part D service access within urban, suburban and rural areas. The urban-rural-two-step floating catchment area measures were compared to traditional two-step floating catchment area measures computed using three fixed catchment area sizes (2, 5, and 15 miles) by visually examining their spatial distributions. Associations between the four pharmacy accessibility measures and selected socio-demographics are calculated using Spearman's rank-order correlation and further compared. The urban-rural two-step floating catchment area measure outperforms all the fixed catchment size measures and has the strongest Spearman correlations with the selected census variables. It also reduces the number of census tracts characterized as 'no access' when compared to the original measures. The spatial distribution of urban-rural two-step floating catchment area pharmacy access exhibits a more granular variation across the study area. The results support our hypothesis that spatial access to pharmacies should account for urbanicity/rurality patterns within a region.

Hierarchical two-step floating catchment area (2SFCA) method: measuring the spatial accessibility to hierarchical healthcare facilities in Shenzhen, China

BackgroundSpatial accessibility to healthcare facilities has drawn much attention in health geography. In China, central and local governments have aimed to develop a well-organized hierarchical system of healthcare facilities in recent years. However, few studies have focused on the measurement of healthcare accessibility in a hierarchical service delivery system, which is crucial for the assessment and implementation of such strategies.MethodsBased on recent improvements in 2SFCA (two-step floating catchment area) method, this study aims to propose a Hierarchical 2SFCA (H2SFCA) method for measuring spatial accessibility to hierarchical facilities. The method considers the varied catchment area sizes, distance decay effects, and transport modes for facilities at various levels. Moreover, both the relative and absolute distance effects are incorporated into the accessibility measurement.ResultsThe method is applied and tested in a case study of hierarchical healthcare facilities in Shenzhen, China. The results reveal that the general spatial accessibility to hierarchical healthcare facilities in Shenzhen is unevenly distributed and concentrated. The disparity of general accessibility is largely caused by the concentrated distribution of tertiary hospitals. For facilities at higher levels, average accessibility of demanders is higher, but there are also larger disparities in spatial accessibility. The comparison between H2SFCA and traditional methods reveals that traditional methods underestimate the spatial disparity of accessibility, which may lead to biased suggestions for policy making.ConclusionsThe results suggest that the supply of healthcare resources at primary facilities is far from sufficient. To improve the spatial equity in spatial accessibility to hierarchical healthcare facilities, various actions are needed at different levels. The proposed H2SFCA method contributes to the modelling of spatial accessibility to hierarchical healthcare facilities in China and similar environments where the referral system has not been well designed. It can also act as the foundation for developing more comprehensive measures in future studies.

Modeling the Optimal Transportation for Acute Stroke Treatment

PurposeProlonged transfer times between the primary stroke center (PSC) and the comprehensive stroke center (CSC) are one of the major causes of treatment delay for endovascular stroke treatment. We aimed to analyze the effect of the diurnal variations in traffic rates at weekdays and weekends on the catchment area size of three transportation paradigms, i.e. mothership, drip-and-ship (DS) and drip-and-drive (DD).MethodsA conditional probability model that predicts the probability of good outcome for patients with suspected large vessel occlusion was used to analyze the prehospital stroke triage in northwest Germany and produce catchment area maps. Transportation times were calculated during each hour of a weekday and a Sunday using Google Maps. For comparison, real DD transportation times from our CSC in Hamburg-Eppendorf (blinded for review) to a PSC in Lüneburg were prospectively recorded.ResultOn weekdays, the mothership catchment area was the largest (≥40,000 km2, 63%) except for a decrease during morning rush hours, when the DD catchment area was highest (30,879 km2, 48%). The DS catchment area was higher than the DD catchment area during the afternoon rush hours both during the week as well as on Sundays.ConclusionOur study showed a considerable impact of the diurnal variations in traffic rate and direction of travel on optimal stroke transportation. Stroke systems of care should take real time traffic information into account.

PALLiON \u2013 PALLiative care Integrated in ONcology: study protocol for a Norwegian national cluster-randomized control trial with a complex intervention of early integration of palliative care

BackgroundSeveral publications have addressed the need for a systematic integration of oncological care focused on the tumor and palliative care (PC) focused on the patient with cancer. The exponential increase in anticancer treatments and the high number of patients living longer with advanced disease have accentuated this. Internationally, there is now a persuasive argument that introducing PC early during anticancer treatment in patients with advanced disease has beneficial effects on symptoms, psychological distress, and survival.MethodsThis is a national cluster-randomized trial (C-RCT) in 12 Norwegian hospitals. The trial investigates effects of early, systematic integration of oncology and specialized PC in patients with advanced cancer in six intervention hospitals compared with conventional care in six. Hospitals are stratified on the size of local catchment areas before randomization. In the intervention hospitals, a three-part complex intervention will be implemented. The backbone of the intervention is the development and implementation of patient-centered care pathways that contain early, compulsory referral to PC and regular and systematic registrations of symptoms. An educational program must be completed before patient inclusion. A total of 680 patients with advanced cancer and one caregiver per patient are included when patients come for start of last line of chemotherapy, defined according to national treatment guidelines. Data registration, clinical variables, and patient- and caregiver-reported outcomes take place every 2 months for 1 year or until death. The primary outcome is use of chemotherapy in the last 3 months of life by comparing the proportion of patients who receive this in the intervention and control groups. Primary outcome is use of chemotherapy in the last 3 months before death, i.e. number of patients. Secondary outcomes are initiation, discontinuation and number of cycles, last 3 months of life, administration of other medical interventions in the last month of life, symptom burden, quality of life (QoL), satisfaction with information and follow-up, and caregiver health, QoL, and satisfaction with care.DiscussionResults from this C-RCT will be used to raise the awareness about the positive outcomes of early provision of specialized palliative care using pathways for patients with advanced cancer receiving medical anticancer treatment. The long-term clinical objective is to integrate these patient-centered pathways in Norwegian cancer care. The specific focus on the patient and family and the organization of a predictable care trajectory is consistent with current Norwegian strategies for cancer care.Trial registrationClinicalTrials.gov, NCT03088202. Registered on 23 March 2017.

Polycyclic Aromatic Hydrocarbons in Bottom Sediments of Selected Anthropogenic Reservoirs in Terms of Catchment Area Development

The polycyclic aromatic hydrocarbon (PAH) concentration in the bottom sediments of the selected dam reservoirs is related to the catchment area size and length of the watercourse that supplies the reservoir. The anthropopressure increases the ratio of the PAH concentration sum G4 group to the G1 group. For the urban-industrial catchment area, the ratio is 1; for the agricultural and agricultural-forestral catchment area, the ratio is between 4 and 9. The elongated down time of surface run-offs helps to retain and degrade 2- and 3-ring PAHs, which is reflected in the high G4:G1 ratio value. Consequently, the pollutants are quickly delivered to the reservoirs and deposited in the bottom sediments. Under such conditions, the G4:G1 ratio is 1. The way in which the catchment area is developed shapes the proportions between the PAH groups that differ in the number of aromatic rings in their molecules. The toxicity, mutagenicity, and carcinogenicity coefficients calculated for the bottom sediments demonstrate that the limnic ecosystems supplied with water from the watercourses with urban-industrial catchment areas are far more threatened than the reservoirs supplied with watercourses with the agricultural catchment areas or catchment areas with a significant share (40–50%) of farming land.

Techno-economic assessment of non-sterile batch and continuous production of lactic acid from food waste

Non-sterile lactic acid (LA) fermentation of highly viscous food waste was demonstrated in batch and continuous flow fermentations. With Streptococcus sp., an indigenous consortium, and/or applied glucoamylase, food waste was fermented without addition of external carbon or nitrogen sources. Experimental results were used for economic and energy evaluations under consideration of different catchment area sizes from 50,000 to 1,000,000 inhabitants. During batch mode, addition of glucoamylase resulted in a titer (after 24 h), yield, and productivity of 50 g L−1, 63%, and 2.93 g L−1h−1, respectively. While titer and yield were enhanced, productivity was lower during continuous operation and 69 g L−1, 86%, and 1.27 g L−1h−1 were obtained at a dilution rate of 0.44 d−1 when glucoamylase was added. Both batch and continuous flow fermentations were found economically profitable with food waste from 200,000 or more inhabitants.