Automatic static cost analysis infers information about the resources used by programs without actually running them with concrete data and presents such information as functions of input data sizes. Most of the analysis tools for logic programs (and many for other languages), as CiaoPP, are based on setting up recurrence relations representing (bounds on) the computational cost of predicates and solving them to find closed-form functions. Such recurrence solving is a bottleneck in current tools: many of the recurrences that arise during the analysis cannot be solved with state-of-the-art solvers, including computer algebra systems (CASs), so that specific methods for different classes of recurrences need to be developed. We address such a challenge by developing a novel, general approach for solving arbitrary, constrained recurrence relations, that uses machine learning (sparse-linear and symbolic) regression techniques to guess a candidate closed-form function, and a combination of an SMT-solver and a CAS to check whether such function is actually a solution of the recurrence. Our prototype implementation and its experimental evaluation within the context of the CiaoPP system show quite promising results. Overall, for the considered benchmark set, our approach outperforms state-of-the-art cost analyzers and recurrence solvers and can find closed-form solutions, in a reasonable time, for recurrences that cannot be solved by them.

Introduction: Point-of-care ultrasound (POCUS) is an integral tool in the modern emergency physician's toolkit. Evidence suggests many imaging and lab investigations are ordered without true medical indications; it is unknown how POCUS utilization impacts health care costs at a patient level. The purpose of this study was to assess whether POCUS use in the emergency department (ED) was associated with cost savings via decreased laboratory and radiographic testing. Methods: POCUMON is a single-center, prospective pilot study. The participants were a convenience sample of ED staff physicians and PGY-5 Emergency Medicine (EM) residents working in the ED from July-October 2019. Physicians who used POCUS as part of their assessment had the cost of their patient investigation plans compared with those proposed by a control group of ED physicians simultaneously on-shift. The control group was blinded to the POCUS findings but had access to the patient and medical record. The lab investigations and imaging studies ordered by both groups were recorded with respective costs. Data were analyzed using a paired T-test, with sub-group analyses. Ethics approval was obtained from the Queen's University HSREB (No.6026732). Results: 50 patient assessments using POCUS were captured in the study period. 76% of patient assessments were performed by EM staff physicians; 94% of control assessments were provided by EM staff physicians. Patient chief complaints included abdominal pain (7), chest pain/dyspnea (10), flank pain (3), pregnancy concerns (4), trauma (7), extremity complaints (4), back pain (3), and other (12). The POCUS group had a trend for lower number of laboratory tests (4.7 ± 0.44 vs 5.22 ± 0.39; p = 0.28) and imaging studies (0.94 ± 0.14 vs 1.1 ± 0.11; p = 0.33). Overall health care costs were similar in both groups, with a trend to cost savings in the POCUS group ($142.00 ± 15.44 vs $174.60 ± 17.00; p = 0.12). Subgrouping identified significant cost savings in the POCUS group for patients with a chief complaint of flank pain ($43.64 vs $248.82, p = 0.01). Conclusion: POCUS use was not associated with significant health care cost savings. ED POCUS usage did see a trend towards decreased laboratory and imaging investigations. Patients presenting with flank pain had significantly lower expenditures associated with their visit when POCUS was incorporated into their assessment. Large scale prospective studies are needed to investigate if POCUS is associated with cost-savings in ED patients.

Insomnia affects about one-third of the population, and is associated with increased morbidity and mortality, reduced production and higher rates of accidents. This suggests that insomnia may burden society with significant cost. However, a precise economic analysis of insomnia is a challenge. Insomnia is part of a very complex interplay of physical and psychological illness, functioning both as a cause and as a consequence. In this paper, some of the methodological issues related to an economic analysis of insomnia are discussed. Data is presented using an economic analysis as an organizer, thus illustrating what conclusions can be drawn, and where further research is needed.

Control-flow refinement refers to program transformations whose purpose is to make implicit control-flow explicit, and is used in the context of program analysis to increase precision. Several techniques have been suggested for different programming models, typically tailored to improving precision for a particular analysis. In this paper we explore the use of partial evaluation of Horn clauses as a general-purpose technique for control-flow refinement for integer transitions systems. These are control-flow graphs where edges are annotated with linear constraints describing transitions between corresponding nodes, and they are used in many program analysis tools. Using partial evaluation for control-flow refinement has the clear advantage over other approaches in that soundness follows from the general properties of partial evaluation; in particular, properties such as termination and complexity are preserved. We use a partial evaluation algorithm incorporating property-based abstraction, and show how the right choice of properties allows us to prove termination and to infer complexity of challenging programs that cannot be handled by state-of-the-art tools. We report on the integration of the technique in a termination analyzer, and its use as a preprocessing step for several cost analyzers.

Purpose: A peripherally inserted central catheter (PICC) is a useful option in providing secure venous access, which enables patients to be discharged earlier with the provision of home care. The objective was to identify the costs associated with having a PICC from a societal perspective, and to identify factors that are associated with total PICC costs.

Methods: Data were obtained from a retrospective cohort of 469 hospitalized pediatric patients with PICCs inserted. Both direct and indirect costs were estimated from a societal perspective. Insertion costs, complication costs, nurse and physician assessment costs, inpatient ward costs, catheter removal costs, home care costs, travel costs, and the cost associated with productivity losses incurred by parents were included in this study.

Results: Based on catheter dwell time, the median total cost associated with a PICC per patient per day (including inpatient hospital costs) was $3,133.5 ($2,210.7–$9,627.0) in 2017 Canadian dollars ($1.00USD = $1.25CAD in 2017). The adjusted mean cost per patient per day was $2,648.2 ($2,402.4–$2,920.4). Excluding inpatient ward costs, the median total and adjusted costs per patient per day were $198.8 ($91.8–$2,475.8) and $362.7($341.0–$386.0), respectively. Younger age, occurrence of complications, more catheter dwell days, wards with more intensive care, and the absence of home care were significant factors associated with higher total PICC costs.

Conclusions: This study has demonstrated the costs associated with PICCs. This information may be helpful for healthcare providers to understand PICC related cost in children and resource implications.

Twelve sequential herbicide treatments were compared to cycloate (S-ethyl N-ethylthiocyclohexanecarbamate), a standard treatment, for control of annual weeds in sugarbeets (Beta vulgaris L.) in three field experiments conducted from 1971 through 1977. At harvest, seven sequential treatments had less than 10 annual broadleaf weeds per 30 m of row, whereas there were 40 broadleaf weeds per 30 m of row for the cycloate treatment. Four of these sequential treatments had significantly higher root yields and net returns than the cycloate treatment. Dependent on the sequential treatment and year, tonnage was increased 7.3 to 20.3 t/ha, and net returns $150 to $515/ha above those with cycloate. The most effective sequential treatment for control of weeds was a preplanting mixture of 2.2 kg/ha of ethofumesate [(±)-2-ethoxy-2,3-dihydro-3,3-dimethyl-5-benzofuranyl methanesulfonate] plus 1.7 kg/ha of diclofop {2-[4-(2,4-dichlorophenoxy)phenoxy] propanoic acid} followed by a postemergence mixture of 0,6 kg/ha each of desmedipham [ethyl m-hydroxycarbanilate carbanilate (ester)] plus phenmedipham (methyl m-hydroxycarbanilate m-methylcarbanilate). This sequential herbicide treatment increased root yields by an average of 20.3 t/ha and net returns by $515/ha above those with cycloate.

Introduction: Syncope is a common emergency department (ED) presentation and constitutes 1% of all ED visits, approximately 160,000 visits annually across Canada. Lack of standardized syncope care has economic and cost implications. Currently, emergency medical services (EMS) is over utilized, variations in ED management exist and a substantial proportion (46.5%) are hospitalized for cardiac monitoring. Our previous studies have proposed ways to reduce health care utilization through development of EMS clinical decision tool, ED risk scores and remote cardiac monitoring. We sought to: 1) Estimate costs associated with syncope care in the pre-hospital, ED and inpatient settings; and 2) Determine potential cost savings if the proposed alternate strategies were adopted. Methods: A prospective cohort study was conducted in five Canadian EDs from 2010-2014. We enrolled adult (≥16 years) syncope patients and excluded those with prolonged loss of consciousness, mental status changes, seizure, significant trauma, or alcohol/illicit drug abuse. Demographics, medical history, mode of arrival, EMS time points, reasons for hospitalization, ED and inpatient length of stay, final ED diagnosis and any serious adverse event within 30 days of index visit were collected. Descriptive and inferential statistics were used. Results: Out of 4,064 patients enrolled, 67.3% were transported to the ED by EMS and the average cost per event was $262.78 (range at study sites: $156.43-$553.03). The average cost per ED visit was $267.98 (range: $174.66-$374.95). 12.9% of the patients were admitted and the average of cost per admission was $9,886.15 (range: $9,715.23-$10,277.98). Syncope is associated with an estimated total annual cost of $257 million. In Canada, we estimate that diverting low-risk patients will save $5 million in the pre-hospital setting and $15 million in the ED annually, and implementing a remote cardiac monitoring strategy will save $50 million annually. Conclusion: It is estimated that the proposed strategies will save $70 million annually. This is likely an underestimation as cost savings due to reduction in investigations related to diversion of ED patients, reduction in ED length of stay and hospitalization are unaccounted. Adoption of similar strategies will likely lead to significantly higher cost savings in countries with higher resource utilization for syncope management.

Introduction: In the context of a shrinking healthcare budget, poor physician cost awareness, and continued over-utilization of low-value tests in the emergency department, we re-designed our computerized order entry system to reduce the use of coagulation testing. Methods: A hospital-based prospective pre-post analysis following de-bundling of INRPTT testing in two academic hospital emergency departments (annual visits 140,000). All participants aged 18 years or older undergoing evaluation and/or treatment at either of during the period of August 1, 2015 to July 24, 2016 were included. Primary outcome is coagulation testing utilization rates and associated costs. Results: Unbundling INR and aPTT testing resulted in significantly decreased bundled INRPTT testing relative to baseline (INRPTT tests per patient per day: 0.60 [95% CI: 0.57-0.62] vs. 0.98 [95% CI: 0.98-0.99], p=0.000), with significantly increased targeted testing (INR tests per patient per day: 0.39 [95% CI: 0.37-0.42] vs. 0.00 [95% CI: 0.00-0.01], p=0.000; PTT tests per patient per day: 0.33 [95% CI: 0.30-0.36] vs. 0.01 [95% CI: 0.00-0.01], p=0.000). As a result of unbundling, there was a significant decrease in costs associated with coagulation testing relative to baseline (Cost per day: $958.52 [INRPTT $592.78+INR $183.91+PTT $181.83] vs. $1,074.50 [INRPTT $1,069.76+INR $2.06+PTT $2.68], p=0.000), realizing estimated daily and yearly savings of $115.98 and $42,332.70, respectively. Conclusion: Compared to baseline practice patterns, unbundling coagulation testing resulted in the reduction of coagulation testing suggesting system design and user workflows to be an integral factor to provider practice patterns. Given the significant cost-savings, we recommend institutions carefully re-evaluate their system design and user workflows to optimize emergency department laboratory utilization.

Meat goat enterprise efficiency was estimated using an input distance function (IDF) by applying stochastic production frontier techniques for the southeastern U.S. region. We found increasing returns to scale and scope economies for southeastern U.S. meat goat enterprises. Mean technical efficiency was 0.81. Our results suggest southeastern U.S. meat goat enterprises can be scale efficient if their size of operation is >~60 goats or >40 breeding does. Cost and IDF analyses show input expenses decreased substantially with increasing scale of operations in southeastern U.S. meat goat production. Empirical Monte Carlo simulation techniques show consistency of small-sample properties for the IDF.

Background: Healthcare use and costs are about 81% higher for morbidly obese individuals compared to non-obese persons, and 47% higher compared to the non-morbidly obese population. The benefits of bariatric surgery for health are well established, but its mid-term impact on healthcare use and costs remains controversial.

Methods: This study examines the trends in healthcare use and costs in a Brazilian cohort during a 4-year period before and after surgery. Healthcare use and direct costs related to inpatients and outpatients were retrieved from a healthcare insurance company database from which all cohort members were selected.

Results: Between 2004 and 2010, 4,006 individuals underwent bariatric surgery. Most patients were female (80%) with a mean age of 36.2 years and a mean body mass index of 42.8 kg/m2. Elevated blood pressure was present in 38% of cases and diabetes was found in 12.5% of subjects. Hospital admissions increased consistently after surgery, even after excluding hospitalizations for esthetic surgery and pregnancy-related care. The most prevalent conditions in this group were gastrointestinal diseases. Emergency department visits increased after bariatric procedures, in particular for genitourinary and hematologic problems. Adjusted costs were higher after surgery as assessed during a 4-year follow-up period.

Conclusion: Results indicate that costs and hospital admissions after bariatric surgery increase following this procedure, even when elective interventions are excluded. Healthcare providers and policy makers need to be aware that a decrease in obesity-related diseases following bariatric surgery does not reduce healthcare use and costs.