The three Is of public schools: irrelevant inputs,insufficient resources and inefficiency

We examine the educational production function and efficiency of public school districts in Illinois. Using non-parametric kernel methods, we find that most traditional schooling inputs are irrelevant in determining test scores (even in a very general setting). Property tax caps are the only relevant factor that is related to districts’ financial constraints and have predominantly negative associations with test scores. Therefore, insufficient resources may be partially responsible for the lack of growth in test scores. For most other relevant inputs, we find substantial heterogeneity in the returns, which helps reconcile some of the puzzling results in the literature. We further find that there exist inefficiencies in school districts. Moreover, the level of test scores, commonly used as a measure of school effectiveness, (while related) differs substantially from our efficiency scores, and standard parametric approaches drastically underestimate school efficiency. We discuss the policy implications of our results.     

Intertemporal production and intertemporal substitution in output supply and input demand

This article presents an intertemporal model of production with multiple inputs to investigate substitution opportunities facing firms over time. The firm’s intertemporal profit maximization problem is characterized with the familiar cost function, and various intertemporal substitution elasticities are delineated for output supply and input demand. The absence of intertemporal substitution in production can imply production smoothing, and allowance for intertemporal substitution in labour demand reinforces the prediction of the real business cycle model. For aggregate US manufacturing, we find substantial substitution in output supply and labour demand over time due to intertemporal changes in output price and wage rates.     

Pseudolikelihood estimation of the stochastic frontier model

Stochastic frontier analysis is a popular tool to assess firm performance. Almost universally it has been applied using maximum likelihood (ML) estimation. An alternative approach, pseudolikelihood (PL) estimation, which decouples estimation of the error component structure and the production frontier, has been adopted in both the non-parametric and panel data settings. To date, no formal comparison has yet to be conducted comparing these methods in a standard, parametric cross-sectional framework. We produce a comparison of these two competing methods using Monte Carlo simulations. Our results indicate that PL estimation enjoys almost identical performance to ML estimation across a range of scenarios and performance metrics, and for certain metrics, outperforms ML estimation when the distribution of inefficiency is incorrectly specified.     

Burden of illness for super-refractory status epilepticus patients

Objective: To provide an estimate of the annual number of super-refractory status epilepticus (SRSE) cases in the US and to evaluate utilization of hospital resources by these patients.

Methods: The Premier Hospital Database was utilized to estimate the number of SRSE cases based on hospital discharges during 2012. Discharges were classified as SRSE cases based on an algorithm using seizure-related International Classification of Diseases-9 (ICD-9) codes, Intensive Care Unit (ICU) length of stay (LOS), and treatment protocols (e.g. benzodiazepines, anti-epileptic drugs (AEDs), and ventilator use). Secondary analyses were conducted using more restrictive algorithms for SRSE.

Results: A total of 6,325 hospital discharges were classified as SRSE cases from a total of 5,300,000 hospital discharges. Applying a weighting based on hospital characteristics and 2012?US demographics, this projected to an estimated 41,156 cases of SRSE in the US during 2012, an estimated incidence rate of ～13/100,000 annually for SRSE in the US. Secondary analyses using stricter SRSE algorithms resulted in estimated incidence rates of ～11/100,000 and 8/100,000 annually. The mean LOS for SRSE hospitalizations was 16.5 days (median =11; interquartile range [IQR]?=?6–20), and the mean ICU LOS was 9.3 days (median =6; IQR =3–12). The mean cost of an SRSE hospitalization was $51,247 (median = $33,294; 95% CI = $49,634–$52,861).

Limitations: The analysis uses ICD-9 diagnostic codes and claims information, and there are inherent limitations in any methodology based on treatment protocol, which created challenges in distinguishing with complete accuracy between SRSE, RSE, and SE on the basis of care patterns in the database.

Conclusion: SRSE is associated with high mortality and morbidity, which place a high burden on healthcare resources. Projections based upon the findings of this study suggest an estimated 25,821–41,959 cases of SRSE may occur in the US each year, but more in-depth studies are required.     

Healthcare and economic burden of adverse events among patients with chronic myelogenous leukemia treated with BCR-ABL1 tyrosine kinase inhibitors

Objectives: BCR-ABL1 tyrosine kinase inhibitors (TKIs) are established treatments for chronic myelogenous leukemia (CML); however, they are associated with infrequent, but clinically serious adverse events (AEs). The objective of this analysis was to assess healthcare resource utilization and costs associated with AEs, previously identified using the FDA Adverse Event Reporting System (FAERS) in another study, among TKI-treated patients.

Methods: Adult patients with ≥1 inpatient or ≥2 outpatient ICD-9-CM diagnosis codes for CML and ≥1 claim for a TKI treatment between January 1, 2006 and September 30, 2012 were identified from the Commercial and Medicare MarketScan databases. The first claim for a TKI was designated as the index event. Patients were required to have no TKI treatment during a 12-month baseline period. Healthcare resource utilization and costs associated with select AEs having the strongest association with TKI treatment (femoral arterial stenosis [FAS], peripheral arterial occlusive disease [PAOD], intermittent claudication, coronary artery stenosis [CAS], pericardial effusion, pleural effusion, malignant pleural effusion, conjunctival hemorrhage) were evaluated during a 12-month follow-up period.

Results: The study sample included 2,005 CML patients receiving TKI therapy (mean age?=?56 years; 56% male). Among all evaluated AEs, the highest mean inpatient healthcare costs were observed for FAS ($16,800 per patient) and PAOD ($14,263 per patient), which had total mean medical costs (inpatient?+?outpatient) of $17,015 and $15,154 per patient, respectively. Mean outpatient healthcare costs were highest for CAS ($1,861 per patient), followed by intermittent claudication ($947 per patient), PAOD ($891 per patient), and pleural effusion ($890 per patient). Total mean medical costs for fluid retention-related AEs, including pericardial effusion and pleural effusion, were $2,797 and $1,908 per patient, respectively.

Conclusions: The healthcare costs of AEs identified in the FAERS as having the strongest association with TKI treatment are substantial. Vascular stenosis-related AEs, including FAS and PAOD, have the highest cost burden.     

Resource utilization and procedure-related costs associated with transfemoral transcatheter aortic valve replacement

Aims: Transcatheter aortic valve implantation (TAVI) is an alternative to surgical valve replacement for patients with aortic stenosis (AS). This study assessed the impact of changing from a self-expandable (SE) valve to a balloon-expandable (BE) valve on healthcare resource use and procedural costs in a population of inoperable AS patients.

Methods: In this retrospective single center study, data for 195 patients who received either an SE or a BE valve between 2010–2014 were collected. Procedural and post-procedural healthcare resource use and cost parameters were determined for the two groups.

Results: The study showed that overall procedural time, including time required by medical personnel, was significantly shorter for TAVI using a BE compared with an SE valve. Post-surgery, patients in the BE valve group had significantly shorter hospital stays than the SE valve group, including significantly fewer days spent in the intensive care unit (ICU). Additionally, trends towards reduced 30-day mortality, incidence of new permanent pacemaker implantation, and incidence of blood transfusion were observed in the BE valve group compared with the SE valve group. Finally, total procedural costs were 24% higher in the SE compared with the BE valve group.

Limitations: The BE valve data were acquired in a single year, whereas the SE valve data were from a 5-year period. However, a year-by-year analysis of patient characteristics and study outcomes for the SE valve group showed few significant differences over this 5-year period.

Conclusions: Overall, changing from an SE to a BE valve for TAVI in patients with severe AS reduced both healthcare resource use and procedure-related costs, while maintaining patient safety. For healthcare providers, this could increase efficiency and capacity within the healthcare system, with the added advantage of reducing costs.     

Current and projected patient and insurer costs for the care of patients with non-small cell lung cancer in the United States through 2040

Aims: The objective of this study was to quantify the current and to project future patient and insurer costs for the care of patients with non-small cell lung cancer in the US.

Materials and methods: An analysis of administrative claims data among patients diagnosed with non-small cell lung cancer from 2007–2015 was conducted. Future costs were projected through 2040 based on these data using autoregressive models.

Results: Analysis of claims data found the average total cost of care during first- and second-line therapy was $1,161.70 and $561.80 for patients, and $45,175.70 and $26,201.40 for insurers, respectively. By 2040, the average total patient out-of-pocket costs are projected to reach $3,047.67 for first-line and $2,211.33 for second-line therapy, and insurance will pay an average of $131,262.39 for first-line and $75,062.23 for second-line therapy.

Limitations: Claims data are not collected for research purposes; therefore, there may be errors in entry and coding. Additionally, claims data do not contain important clinical factors, such as stage of disease at diagnosis, tumor histology, or data on disease progression, which may have important implications on the cost of care.

Conclusions: The trajectory of the cost of lung cancer care is growing. This study estimates that the cost of care may double by 2040, with the greatest proportion of increase in patient out-of-pocket costs. Despite the average cost projections, these results suggest that a small sub-set of patients with very high costs could be at even greater risk in the future.     

Real-life cost of vitamin K antagonist treatment in patients with non-valvular atrial fibrillation in France in 2013

Aims: Data highlighting the cost drivers for non-valvular atrial fibrillation (NVAF) patients in terms of vitamin K antagonist (VKA) treatment and monitoring are lacking in France. This study aimed to evaluate the real-life daily cost of VKA treatment in 2013, in French patients suffering from NVAF.

Methods: This longitudinal observational study was performed using the EGB (Echantillon Généraliste des Bénéficiaires) database, a random sample of the French national insurance (NHI) database, which covers 80% of the population. All adult patients whose first NVAF anticoagulant treatment in 2013 was a VKA were analyzed. Costs were calculated for the duration of follow-up and then divided by the number of days of therapy. The analysis was performed both from the French NHI perspective (amount reimbursed by the NHI) and from a collective perspective.

Results: In this study, 3,254 NVAF patients treated with VKA in 2013 were included, and this sample comprised 52.6% males. The mean daily cost of VKA treatment was €1.13 (±1.18) according to the collective perspective (89.4% of this cost was associated to INR measurement) and €1.05 (±1.16) according to the NHI perspective.

Limitations: As diagnoses associated with procedures are not available in the EGB database, proxies were used, and an algorithm was created to define the AF population.

Conclusions: This analysis is the first to consider an exhaustive spectrum of the costs of VKA treatment in France using EGB data. VKA medication requires exhaustive follow-up, and, thus, associated costs are important. The results of the present study confirmed this close follow-up for VKA patients, making the cost of treatment by VKA nearly 10-times more expensive than the cost of medication itself.     

von Thünen: Capital,Production Functions,Marginal Productivity Wages,and the Natural Wage

This paper puts seminal contributions to theory of production functions and maximization of explicit quantitative objective functions by Johann Heinrich von Thünen into a systematic historical perspective. We show that his comprehensive ‘Tableau Economiques’ do imply two exact parametric production functions. Moreover, the renowned ‘geometric mean wage’ formula is restated as an exact CES marginal labor productivity wage for σ = 2. We review four alternative modes of normative (natural) wage calculations without an explicit production function, and conclude that von Thünen's natural wage differentiation formulas are bona fide alternatives for deriving the natural wage formula.     

基于计算实验方法的地铁工程成本管控行为激励机理研究

发展城市地铁是城市轨道交通建设的主导方向,也是地铁建设企业实现可持续发展的重要保障。大规模地铁建设需要对成本管控行为的机理、规律有进一步认识和研究。基于激励视角,识别了我国地铁工程成本管控行为激励因素,运用计算实验方法建立模型,设计实验情景,设置实验参数,研究了激励因素对地铁工程成本管控行为的作用机理。实验结果表明：环境、工作、回报、管理因素对地铁工程成本管控行为变化具有显著影响。其中,环境因素具有调节作用,工作因素具有推动作用,回报因素具有促进作用,管理因素具有引领作用。实验结果可为地铁工程成本管控提供启示与借鉴。