Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/20.500.11779/1926

Browse

Now showing 1 - 20 of 62

Citation - WoS: 13
Citation - Scopus: 14
Economic Outcomes in Patients With Chemotherapy-Naive Metastatic Castration-Resistant Prostate Cancer Treated With Enzalutamide or Abiraterone Acetate Plus Prednisone
(Springer, 2020) Lechpammer, Stanislav; Ramaswamy, Krishnan; Wang, Li; Mardekian, Jack; George, Daniel J.; Sandin, Rickard; Schultz, Neil M.; Başer, Onur; Huang, Ahong
Introduction: Prostate cancer (PC) is the second leading cause of cancer death among US men and accounts for considerable healthcare expenditures. We evaluated economic outcomes in men with chemotherapy-naı¨ve metastatic castration-resistant PC (mCRPC) treated with enzalutamide or abiraterone acetate plus prednisone (abiraterone). Methods: We performed a retrospective analysis on 3174 men (18 years or older) utilizing the Veterans Health Administration (VHA) database from 1 April 2014 to 31 March 2018. Men with mCRPC were included if they had at least one pharmacy claim for enzalutamide or abiraterone (ﬁrst claim date = index date) following surgical or medical castration, had no chemotherapy treatment within 12 months prior to the index date, and had continuous VHA enrollment for at least 12 months pre- and post-index date. Men were followed until death, disenrollment, or end of study and were 1:1 propensity score matched (PSM). All-cause and PC-related resource use and costs per patient per month (PPPM) in the 12 months post index were compared between matched cohorts. Results: We identiﬁed 1229 men with mCRPC prescribed enzalutamide and 1945 prescribed abiraterone with mean ages of 74 and 73 years, respectively. After PSM, each cohort had 1160 patients. The enzalutamide cohort had fewer all-cause (2.51 vs 2.86; p\0.0001) and PC-related outpatient visits (0.86 vs 1.03; p\0.0001), with corresponding lower all-cause ($2588 vs $3115; p\0.0001) and PC-related ($1356 vs $1775; p\0.0001) PPPM outpatient costs compared with the abiraterone cohort. Allcause total costs (medical and pharmacy) PPPM ($8085 vs $9092; p = 0.0002) and PC-related total costs PPPM ($6321 vs $7280; p\0.0001) were signiﬁcantly lower in the enzalutamide cohort compared with the abiraterone cohort. Conclusions: Enzalutamide-treated men with chemotherapy-naı ¨ve mCRPC had signiﬁcantly lower resource utilization and healthcare costs compared with abiraterone-treated men. Plain Language Summary: Plain language summary available for this article.
Citation - WoS: 18
Citation - Scopus: 18
Guns and Homicides: a Multiscale Geographically Weighted Instrumental Variables Approach
(Wiley, 2019) Bilgel, Fırat
This article assesses the locally varying effects of gun ownership levels on total and gun homicide rates in the contiguous United States using cross-sectional county data for the period 2009–2015. Employing a multiscale geographically weighted instrumental variables regression that takes into account spatial nonstationarity in the processes and the endogenous nature of gun ownership levels, estimates show that gun ownership exerts spatially monotonically negative effects on total and gun homicide rates, indicating that there are no counties supporting the “more guns, more crime” hypothesis for these two highly important crime categories. The number of counties in the contiguous United States where the “more guns, less crime” hypothesis is confirmed is limited to at least 1258 counties (44.8% of the sample) with the strongest total homicide-decreasing effects concentrated in southeastern Texas and the deep south. On the other hand, stricter state gun control laws exert spatially monotonically negative effects on gun homicide rates with the strongest effects concentrated in the southern tip of Texas extending toward the deep south.
Citation - WoS: 8
Citation - Scopus: 8
The Use of Decomposition Methods in Real-World Treatment Benefits Evaluation for Patients With Type 2 Diabetes Initiating Different Injectable Therapies: Findings From the Initiator Study
(2017) Ke, Xuehua; Buysman, Erin; Wei, Wenhui; Xie, Lin; Grabner, Michael; Brekke, Lee; Başer, Onur
Background: Determining characteristics of patients likely to benefit from a particular treatment could help physicians set personalized targets. OBJECTIVES: To use decomposition methodology on real-world data to identify the relative contributions of treatment effects and patients' baseline characteristics. METHODS: Decomposition analyses were performed on data from the Initiation of New Injectable Treatment Introduced after Antidiabetic Therapy with Oral-only Regimens (INITIATOR) study, a real-world study of patients with type 2 diabetes started on insulin glargine (GLA) or liraglutide (LIRA). These analyses investigated relative contributions of differences in baseline characteristics and treatment effects to observed differences in 1-year outcomes for reduction in glycated hemoglobin A1c (HbA1c) and treatment persistence. RESULTS: The greater HbA1c reduction seen with GLA compared with LIRA (-1.39% vs. -0.74%) was primarily due to differences in baseline characteristics (HbA1c and endocrinologist as prescribing physician; P < 0.050). Patients with baseline HbA1c of 9.0% or more or evidence of diagnosis codes related to mental illness achieved greater HbA1c reductions with GLA, whereas patients with baseline polypharmacy (6-10 classes) or hypogylcemia achieved greater reductions with LIRA. Decomposition analyses also showed that the higher persistence seen with GLA (65% vs. 49%) was mainly caused by differences in treatment effects (P < 0.001). Patients 65 years and older, those with HbA1c of 9.0% or more, those taking three oral antidiabetes drugs, and those with polypharmacy of more than 10 classes had higher persistence with GLA; patients 18 to 39 years and those with HbA1c of 7.0% to less than 8.0% had higher persistence with LIRA. CONCLUSIONS: Although decomposition does not demonstrate causal relationships, this method could be useful for examining the source of differences in outcomes between treatments in a real-world setting and could help physicians identify patients likely to respond to a particular treatment. Copyright (C) 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.
Trade Competitiveness in Developing Countries
(2018) Nazlı, Karamollaoğlu
Chapter 7
Citation - Scopus: 1
Heterogeneous Impact of Innovation on Economic Development: Evidence from EU Regions
(Elsevier Sci Ltd, 2026) Pinar, Mehmet; Karahasan, Burhan Can
This paper investigates the heterogeneous impact of innovation on economic development across European Union (EU) regions, with a focus on regional competitiveness driven by innovation-based capabilities. While innovation is a key driver of economic growth, its effects are not uniformly distributed. Using the Multiscale Geographically Weighted Regression models, the study examines how different dimensions of innovation (technological readiness, business sophistication, and overall innovation capacity) affect regional GDP per capita. The results show that regions with higher innovation-based competitiveness generally achieve higher income levels. However, the impact of innovation is spatially uneven. While core EU regions (particularly, in Northern and Western Europe) benefit more strongly from innovation, peripheral regions (in Southern and Eastern Europe) often experience weaker and in some cases even negative, effects. These results highlight the importance of accounting for spatial variation when designing innovation and cohesion policies. The paper calls for tailored, place-based strategies to address regional disparities in innovation-driven development and suggests that current EU policies should be adjusted to better support lagging regions.
Citation - WoS: 3
Citation - Scopus: 4
Does Credit Composition Matter for Current Account Dynamics? Evidence From Turkey
(Taylor & Francis, 2016) Toraganlı, Nazlı; Ertuğrul, Hasan Murat
Based on a dynamic approach using the Kalman filter we depict effects of time-varying interactions between different components of credit stock on the current account in the Turkish Economy for the period 2002Q3–2014Q3. We decompose the credit stock into consumer and non-financial corporate sector credit and show empirically that both types of credit stock have negative effects on the current account dynamics
Citation - WoS: 7
Citation - Scopus: 7
Exchange Rates and Firm Survival: an Examination With Turkish Firm-Level Data
(Elsevier, 2016) Toraganlı, Nazlı; Yazgan, Mustafa Ege
Micro-level empirical research has begun to obtain important results on the effects of currency variations on firms’ survival. The literature has, however, lacked a detailed analysis of the effects of exchange rates on firms’ survival behavior in emerging markets due to a scarcity of firm-level information. Using a firm-level dataset, we investigate the impact of currency appreciation on the survival behavior of Turkish firms in the manufacturing industries for 2002–2009. Our results suggest that real exchange rate appreciation decreases the probability of survival in the manufacturing industries. We also find that high-productivity firms have a higher probability of survival than low- productivity firms following an appreciation of the exchange rate. Our findings indicate that the negative effect of a 1% real appreciation of the domestic currency on the survival probability of a given firm ranges from 4.5 to 9%, providing evidence for the vulnerability of developing countries to exchange rate movements. This evidence indicates that, especially for emerging market economies, economic events and policies leading to an appreciation in the domestic currency should be managed cautiously.
Citation - Scopus: 4
Economic Impact and Complications of Treated and Untreated Hepatitis C Virus Patients in Turkey
(2015) Altinbaş, Akif; Baser E; Kariburyo, F; Başer, Onur
Background: According to the Turkish Ministry of Health’s guidelines,standard double therapy, a combination of pegylated interferon-alphaand ribavirin, was the only treatment option for patients withhepatitis C virus (HCV) infection until the end of 2011. Objective: Theprimary objective was to compare risk-adjusted clinical and economicoutcomes between treated and untreated patients with HCV infection.Methods: Patients with HCV infection were identified from theTurkish National Health Insurance Database (2009–2011) using International Classification of Diseases, 10th Revision, Clinical Modification codes.The first prescription date was designated as the index date. Mortalityand hepatocellular carcinoma (HCC) rates and health care costs oftreated and untreated patients were compared using propensity scorematching. Baseline demographic and clinical factors were controlledin the models. Subgroup analysis was conducted for patient groupswith and without a cirrhosis diagnosis. Results: Out of 12,990 patientsincluded in the study, 1,583 were treated for HCV infection. Out of2,467 patients who had a cirrhosis diagnosis, 231 were treated,whereas out of 10,523 patients without cirrhosis, 1,352 patients weretreated. Treated patients were younger, less likely to be diagnosedwith comorbid conditions, and less likely to reside in Central orEastern Anatolia. After adjusting for baseline demographic andclinical factors, mortality (2.27% vs. 5.31%; P o 0.001) and HCC rates(0.69% vs. 1.96%; P o 0.001) were found to be lower for treatedpatients. Differences were more significant among patients diagnosedwith cirrhosis. Treated patients incurred higher risk-adjusted annualcosts (€6172 vs. €1680; P o 0.001), mainly because of pharmaceuticalcosts (€4918 vs. €583; P o 0.001). Conclusions: HCV infection treatment, although costly, significantly reduces mortality and HCC ratesin Turkey.
Citation - WoS: 9
Citation - Scopus: 11
A Value-Adding Approach To Reliability Under Preventive Maintenance Costs and Its Applications
(2014) Dubey, Rameshwar; Kılıç, Erdem; Ali, Sadia Samar; Weber, Gerhard Wilhelm
No equipment (system) can be perfectly reliable in spite of the utmost care and best efforts on the part of the designer, decision-maker and manufacturer. The two sides of maintenance are corrective and preventive maintenance. It is generally assumed that a preventive maintenance action is less costly than a repair maintenance action. We examine this proposition in detail on the basis of a failure-time model that relates conformance quality to reliability. Illustratively, we present reliability in the context of contracts with asymmetric information. The model shows how to overcome information rents through price distortions and quantity rationing. The paper ends with a conclusion and an outlook to future studies.
Citation - Scopus: 8
Patterns of Treatment and Correction of Hyponatremia in Intensive Care Unit Patients
(W.B. Saunders, 2015) Badawi, Omar; Chiodo, Joseph; Waikar, Sushrut S.; Boklage, Susan; Dasta, Joseph; Xie, Lin; Başer, Onur
Purpose: The goal of this study was to examine the real-world patterns of care and interventions among intensive care unit (ICU) patients with hypervolemic and euvolemic hyponatremia using a large clinical database. Materials and Methods: The Phillips eICU Research Institute database was used to investigate hyponatremia treatment patterns and trends, mortality, and ICU and hospital length of stay. Demographics, clinical characteristics, and outcome variables were compared in patients corrected for hyponatremia using both a more strict and a less strict definition. Results: At admission, 35%, 55%, and 10% of patients had mild, moderate, and severe hyponatremia, respectively. At the end of an ICU stay, the percentage of patients who did not have corrected serum sodium concentration was 48% (using a more strict definition) and 24% (using a less strict definition). Using either definition of correction, patients with serum sodium correction had lower mortality and longer survival than did patients without corrected serum sodium concentration. Conclusions: A significant proportion of hyponatremia is not corrected during an ICU stay. Critically ill patients with hyponatremia who have their serum sodium corrected have lower mortality and longer survival, highlighting the need for more attention to hyponatremia and its correction in critically ill patients. © 2015 Elsevier Inc.
Citation - WoS: 17
Citation - Scopus: 23
Benefit of Early Discharge Among Patients With Low-Risk Pulmonary Embolism
(2017) Wang, Li; Wells, Phil; Fermann, Gregory J; Peacock, W. Frank; Schein, Jeff; Coleman, Craig I; Crivera, Concetta; Başer, Onur
Clinical guidelines recommend early discharge of patients with low-risk pulmonary embolism (LRPE). This study measured the overall impact of early discharge of LRPE patients on clinical outcomes and costs in the Veterans Health Administration population. Adult patients with >= 1 inpatient diagnosis for pulmonary embolism (PE) (index date) between 10/2011-06/2015, continuous enrollment for >= 12 months pre-and 3 months post-index date were included. PE risk stratification was performed using the simplified Pulmonary Embolism Stratification Index. Propensity score matching (PSM) was used to compare 90-day adverse PE events (APEs) [recurrent venous thromboembolism, major bleed and death], hospital-acquired complications (HACs), healthcare utilization, and costs among short (<= 2 days) versus long length of stay (LOS). Net clinical benefit was defined as 1 minus the combined rate of APE and HAC. Among 6,746 PE patients, 95.4% were men, 22.0% were African American, and 1,918 had LRPE. Among LRPE patients, only 688 had a short LOS. After 1:1 PSM, there were no differences in APE, but short LOS had fewer HAC (1.5% vs 13.3%, 95% CI: 3.77-19.94) and bacterial pneumonias (5.9% vs 11.7%, 95% CI: 1.24-3.23), resulting in better net clinical benefit (86.9% vs 78.3%, 95% CI: 0.84-0.96). Among long LOS patients, HACs (52) exceeded APEs (14 recurrent DVT, 5 bleeds). Short LOS incurred lower inpatient ($2,164 vs $5,100, 95% CI: $646.8-$5225.0) and total costs ($9,056 vs $12,544, 95% CI: $636.6-$6337.7). LRPE patients with short LOS had better net clinical outcomes at lower costs than matched LRPE patients with long LOS.
Citation - WoS: 7
Citation - Scopus: 7
Market Access and Regional Dispersion of Human Capital Accumulation in Turkey
(Wiley, 2020) Karahasan, Burhan Can; Bilgel, Fırat
Building on early advances in development economics, the theoretical construct of new economic geography asserts that geography plays a crucial role in educational human capital accumulation. Based on this expectation, this study investigates the impact of market access on provincial human capital accumulation in Turkey. Results indicate that market access matters for understanding why some regions lag behind others in terms of average years of schooling. Our results are robust to the inclusion of spatial mechanisms, different specifications of the spatial weight matrix, endogeneity and alternative measurements of market access and to a host of other factors that affect regional human capital accumulation.
Citation - WoS: 182
Citation - Scopus: 213
Valuable Virality
(2017) Berger, Jonah; Akpınar, Ezgi
Given recent interest in social media, many brands now create content that they hope consumers will view and share with peers. While some campaigns indeed go "viral," their value to the brand is limited if they do not boost brand evaluation or increase purchase. Consequently, a key question is how to create valuable virality, or content that is not only shared but also beneficial to the brand. Share data from hundreds of real online ads, as well as controlled laboratory experiments, demonstrate that compared with informative appeals (which focus on product features), emotional appeals (which use drama, mood, music, and other emotion-eliciting strategies) are more likely to be shared. Informative appeals, in contrast, boost brand evaluations and purchase because the brand is an integral part of the ad content. By combining the benefits of both approaches, emotional brand-integral ads boost sharing while also bolstering brand-related outcomes. The authors' framework sheds light on how companies can generate valuable virality and the mechanisms underlying these effects.
Citation - WoS: 5
Citation - Scopus: 5
Evidence for Financial Contagion in Endogenous Volatile Periods
(Wiley, 2015) Ulusoy, Veysel; Kılıç, Erdem
The objective of this study is to analyze cross-border contagious dynamics in both foreign exchange markets and stock exchange markets. Propagation is analyzed with respect to the transmission of excessive volatility that is endogenously determined. The contagion process is discussed in the context of financial systems, foreign direct investments and trade. Implementing a vector autoregressive-multivariate generalized autoregressive conditional heteroskedasticity (VAR-MGARCH) model, we show that country-specific turbulence in financial markets is able to create unanticipated financial contagion across countries. Diversified trade and financial relations decrease the risk of exposure to contagion from external markets. The world's largest economies, however, play a price-setter role, and diversification is of secondary importance. Asymmetric transmission of the empirically predicted contagion prevails in the latter case.
Citation - WoS: 10
Citation - Scopus: 12
The Topography and Sources of Multidimensional Poverty in Turkey
(Springer, 2021) Karahasan, Burhan Can; Bilgel, Fırat
Economic inequality and poverty have been extensively analyzed in monetary terms. However, other aspects of poverty, such as education, health, environment and standards of living are important factors, essential for human well-being and capabilities. Using a host of non-monetary aspects of poverty, this paper sheds light on the geographical distribution of multidimensional poverty in Turkey. Results from survey data highlight that the regional distribution non-monetary dimensions of poverty is conspicuously different than that of relative monetary poverty in Turkey. Unlike the relative monetary poverty rate, multidimensional poverty measurement reflects the regional underdevelopment problem of Turkey. On the contrary, once monetary poverty is considered in absolute terms, multidimensional and absolute monetary poverty have a similar geographical pattern. Moreover, the decomposition analyses point out that females, old disabled and socially excluded individuals suffer the most from multidimensional poverty. Our combined results show that the isolated eastern regions realize the highest poverty and deprivation at each decomposition level.
Citation - WoS: 18
Citation - Scopus: 18
Adding Rapid-Acting Insulin or Glp-1 Receptor Agonist To Basal Insulin: Outcomes in a Community Setting
(2015) Dalal, Mehul R; DiGenio, Andres; Xie, Lin; Başer, Onur
To evaluate real-world outcomes in patients with type 2 diabetes mellitus (T2DM)receiving basal insulin, who initiate add-on therapy with a rapid-acting insulin (RAI) or aglucagon-like peptide 1 (GLP-1) receptor agonist.Data were extracted retrospectively from a U.S. health claims database. Adults withT2DM on basal insulin who added an RAI (basal+RAI) or GLP-1 receptor agonist (basal+GLP-1) were included. Propensity score matching (1 up to 3 ratio) was used to control for differencesin baseline demographics, clinical characteristics, and health resource utilization. Endpointsincluded prevalence of hypoglycemia, pancreatic events, all-cause and diabetes-relatedresource utilization, and costs at 1 year follow-up. Overall, 6,718 matched patients were included: 5,013 basal+RAI and 1,705basal+GLP1. Patients in both groups experienced a similar proportion of any hypoglycemicevent (P = .4079). Hypoglycemic events leading to hospitalization were higher in the basal+RAIcohort (2.7% vs. 1.8%; P = .0444). The basal+GLP-1 cohort experienced fewer all-cause(13.55% vs. 18.61%; P<.0001) and diabetes-related hospitalizations (11.79% vs. 15.68%;P<.0001). The basal+GLP-1 cohort had lower total all-cause health care costs ($18,413 vs.$20,821; P = .0002), but similar diabetes-related costs ($9,134 vs. $8,985; P<.0001) comparedwith the basal+RAI cohort. Add-on therapy with a GLP-1 receptor agonist in T2DM patients receiving basalinsulin was associated with fewer hospitalizations and lower total all-cause costs compared withadd-on therapy using a RAI, and could be considered an alternative to a RAI in certain patientswith T2DM, who do not achieve effective glycemic control with basal insulin.
Monetary Coordination and Regulation Policies of Spillover Effects on Asset Dynamics
(Springer, 2016) Kılıç, Erdem
In this study we propose a model for excessive volatility regulation. The model dealswith the control of shocks in capital markets. After describing a transmission mechanism thattransfers shocks in a macroeconomic variable, we establish a model how to control the shocks inthe framework. Two economies are considered with alternative constellations in coordination ofpolicies. Spillover effects under coordination are less severe, than the spillover effects under Nashequilibrium in the case of comovements of asset volatilities. In other terms, coordination helps tocure the contagious effects, in the case, where two countries are affected by the same spillovereffect in the same direction.
Citation - WoS: 3
Citation - Scopus: 3
Patterns of International Normalized Ratio Values Among New Warfarin Patients With Nonvalvular Atrial Fibrillation
(2016) Schein, Jeffrey R; Wang, Li; Nelson, Winnie W.; Damaraju, Chandrasekharrao, V; Milentijevic, Dejan; Başer, Onur
Limited information exists regarding the relationship between international normalized ratio (INR) control/stability and the discontinuation of warfarin therapy among patients with nonvalvular atrial fibrillation (NVAF). This study evaluated the association between INR stabilization and warfarin discontinuation and assessed INR patterns before and after INR stabilization among patients (18 years) with NVAF who newly initiated warfarin (Veterans Health Administration datasets; October 1, 2007 through September 30, 2012). Achievement of INR stabilization (3 consecutive in-range therapeutic INR measurements 7 days apart) was examined from warfarin initiation through the end of warfarin exposure. Proportion of time in therapeutic range during warfarin exposure was calculated (Rosendaal method) and categorized as at least 60% or less than 60%. Among 34346 patients, 49.4% achieved INR stabilization (mean time to stabilization, 98 days). Approximately 40% of INR values were out-of-range, even after achieving stabilization. During 30 days following an INR 4.0 or higher, patients had more INR testing than the overall mean (2.51 vs. 1.67 tests). Warfarin discontinuation was 4.2 times more likely among patients without INR stabilization versus those with INR stabilization (P<0.00001). Patients with poor INR control (time in therapeutic range <60%) were 1.76 times more likely to discontinue warfarin within 1 year (P<0.0001). INR stabilization is a better predictor of warfarin discontinuation than poor INR control. Improved approaches are necessary to maintain appropriate anticoagulation levels among patients with NVAF.
Citation - WoS: 5
Citation - Scopus: 5
Health Outcomes Among Patients Diagnosed With Schizophrenia in the Us Veterans Health Administration Population Who Transitioned From Once-Monthly To Once-Every Paliperidone Palmitate: an Observational Retrospective Analysis
(Springer, 2019) Khouyr, Antoine El; Wang, Li; Joshi, Kruti; Patel, Charmi; Başer, Onur; Huang, Ahong
There is limited literature on treatment patterns, healthcare resource utilization (HRU), and costs among patients who transition from once-monthly paliperidone palmitate (PP1M) to once-every-3-month paliperidone palmitate (PP3M) in a real-world setting. Hence, this study compared treatment patterns, HRU, and costs 12-month pre- and post-PP3M transition among Veteran’s Health Administration (VHA) patients with schizophrenia.
Citation - WoS: 4
Citation - Scopus: 6
Does the Unification of Health Financing Affect the Distribution Pattern of Out-Of Health Expenses in Turkey?
(Wiley, 2019) Çınaroğlu, Songül; Başer, Onur
Turkey has implemented health reforms for over a decade and has taken significant steps toward unifying health financing. This study investigated the financial burden associated with out-of-pocket (OOP) expenditures under universal health coverage, using national 2003–2015 household budget data from the Turkish Statistical Institute. Progress was evaluated using Kakwani–Suits indices and Lorenz concentration curves. The results indicate that overall, more than a decade after its unification, redistribution of wealth in the Turkish health financing system has benefitted the wealthy but not the poor. Both curve and index approaches (Kakwani index 2003 = -0.50; 2015 = -0.44) reveal an increasingly regressive pattern of OOP health expenditures. The effective use of fiscal space and good political leadership are essential for the successful continuation of reforms to combat poverty in Turkey.