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Sample records for risks survival analysis

  1. Multivariate survival analysis and competing risks

    CERN Document Server

    Crowder, Martin J

    2012-01-01

    Multivariate Survival Analysis and Competing Risks introduces univariate survival analysis and extends it to the multivariate case. It covers competing risks and counting processes and provides many real-world examples, exercises, and R code. The text discusses survival data, survival distributions, frailty models, parametric methods, multivariate data and distributions, copulas, continuous failure, parametric likelihood inference, and non- and semi-parametric methods. There are many books covering survival analysis, but very few that cover the multivariate case in any depth. Written for a graduate-level audience in statistics/biostatistics, this book includes practical exercises and R code for the examples. The author is renowned for his clear writing style, and this book continues that trend. It is an excellent reference for graduate students and researchers looking for grounding in this burgeoning field of research.

  2. [Survival analysis with competing risks: estimating failure probability].

    Science.gov (United States)

    Llorca, Javier; Delgado-Rodríguez, Miguel

    2004-01-01

    To show the impact of competing risks of death on survival analysis. We provide an example of survival time without chronic rejection after heart transplantation, where death before rejection acts as a competing risk. Using a computer simulation, we compare the Kaplan-Meier estimator and the multiple decrement model. The Kaplan-Meier method overestimated the probability of rejection. Next, we illustrate the use of the multiple decrement model to analyze secondary end points (in our example: death after rejection). Finally, we discuss Kaplan-Meier assumptions and why they fail in the presence of competing risks. Survival analysis should be adjusted for competing risks of death to avoid overestimation of the risk of rejection produced with the Kaplan-Meier method.

  3. Study of Hip Fracture Risk using Tree Structured Survival Analysis

    Directory of Open Access Journals (Sweden)

    Lu Y

    2003-01-01

    Full Text Available In dieser Studie wird das Hüftfraktur-Risiko bei postmenopausalen Frauen untersucht, indem die Frauen in verschiedene Subgruppen hinsichtlich dieses Risikos klassifiziert werden. Frauen in einer gemeinsamen Subgruppe haben ein ähnliches Risiko, hingegen in verschiedenen Subgruppen ein unterschiedliches Hüftfraktur-Risiko. Die Subgruppen wurden mittels der Tree Structured Survival Analysis (TSSA aus den Daten von 7.665 Frauen der SOF (Study of Osteoporosis Fracture ermittelt. Bei allen Studienteilnehmerinnen wurde die Knochenmineraldichte (BMD von Unterarm, Oberschenkelhals, Hüfte und Wirbelsäule gemessen. Die Zeit von der BMD-Messung bis zur Hüftfraktur wurde als Endpunkt notiert. Eine Stichprobe von 75% der Teilnehmerinnen wurde verwendet, um die prognostischen Subgruppen zu bilden (Trainings-Datensatz, während die anderen 25% als Bestätigung der Ergebnisse diente (Validierungs-Datensatz. Aufgrund des Trainings-Datensatzes konnten mittels TSSA 4 Subgruppen identifiziert werden, deren Hüftfraktur-Risiko bei einem Follow-up von im Mittel 6,5 Jahren bei 19%, 9%, 4% und 1% lag. Die Einteilung in die Subgruppen erfolgte aufgrund der Bewertung der BMD des Ward'schen Dreiecks sowie des Oberschenkelhalses und nach dem Alter. Diese Ergebnisse konnten mittels des Validierungs-Datensatzes reproduziert werden, was die Sinnhaftigkeit der Klassifizierungregeln in einem klinischen Setting bestätigte. Mittels TSSA war eine sinnvolle, aussagekräftige und reproduzierbare Identifikation von prognostischen Subgruppen, die auf dem Alter und den BMD-Werten beruhen, möglich. In this paper we studied the risk of hip fracture for post-menopausal women by classifying women into different subgroups based on their risk of hip fracture. The subgroups were generated such that all the women in a particular subgroup had relatively similar risk while women belonging to two different subgroups had rather different risks of hip fracture. We used the Tree Structured

  4. Survival analysis

    International Nuclear Information System (INIS)

    Badwe, R.A.

    1999-01-01

    The primary endpoint in the majority of the studies has been either disease recurrence or death. This kind of analysis requires a special method since all patients in the study experience the endpoint. The standard method for estimating such survival distribution is Kaplan Meier method. The survival function is defined as the proportion of individuals who survive beyond certain time. Multi-variate comparison for survival has been carried out with Cox's proportional hazard model

  5. Survival Analysis

    CERN Document Server

    Miller, Rupert G

    2011-01-01

    A concise summary of the statistical methods used in the analysis of survival data with censoring. Emphasizes recently developed nonparametric techniques. Outlines methods in detail and illustrates them with actual data. Discusses the theory behind each method. Includes numerous worked problems and numerical exercises.

  6. Kaplan-Meier Survival Analysis Overestimates the Risk of Revision Arthroplasty: A Meta-analysis.

    Science.gov (United States)

    Lacny, Sarah; Wilson, Todd; Clement, Fiona; Roberts, Derek J; Faris, Peter D; Ghali, William A; Marshall, Deborah A

    2015-11-01

    Although Kaplan-Meier survival analysis is commonly used to estimate the cumulative incidence of revision after joint arthroplasty, it theoretically overestimates the risk of revision in the presence of competing risks (such as death). Because the magnitude of overestimation is not well documented, the potential associated impact on clinical and policy decision-making remains unknown. We performed a meta-analysis to answer the following questions: (1) To what extent does the Kaplan-Meier method overestimate the cumulative incidence of revision after joint replacement compared with alternative competing-risks methods? (2) Is the extent of overestimation influenced by followup time or rate of competing risks? We searched Ovid MEDLINE, EMBASE, BIOSIS Previews, and Web of Science (1946, 1980, 1980, and 1899, respectively, to October 26, 2013) and included article bibliographies for studies comparing estimated cumulative incidence of revision after hip or knee arthroplasty obtained using both Kaplan-Meier and competing-risks methods. We excluded conference abstracts, unpublished studies, or studies using simulated data sets. Two reviewers independently extracted data and evaluated the quality of reporting of the included studies. Among 1160 abstracts identified, six studies were included in our meta-analysis. The principal reason for the steep attrition (1160 to six) was that the initial search was for studies in any clinical area that compared the cumulative incidence estimated using the Kaplan-Meier versus competing-risks methods for any event (not just the cumulative incidence of hip or knee revision); we did this to minimize the likelihood of missing any relevant studies. We calculated risk ratios (RRs) comparing the cumulative incidence estimated using the Kaplan-Meier method with the competing-risks method for each study and used DerSimonian and Laird random effects models to pool these RRs. Heterogeneity was explored using stratified meta-analyses and

  7. Survival analysis of cancer risk reduction strategies for BRCA1/2 mutation carriers.

    Science.gov (United States)

    Kurian, Allison W; Sigal, Bronislava M; Plevritis, Sylvia K

    2010-01-10

    Women with BRCA1/2 mutations inherit high risks of breast and ovarian cancer; options to reduce cancer mortality include prophylactic surgery or breast screening, but their efficacy has never been empirically compared. We used decision analysis to simulate risk-reducing strategies in BRCA1/2 mutation carriers and to compare resulting survival probability and causes of death. We developed a Monte Carlo model of breast screening with annual mammography plus magnetic resonance imaging (MRI) from ages 25 to 69 years, prophylactic mastectomy (PM) at various ages, and/or prophylactic oophorectomy (PO) at ages 40 or 50 years in 25-year-old BRCA1/2 mutation carriers. With no intervention, survival probability by age 70 is 53% for BRCA1 and 71% for BRCA2 mutation carriers. The most effective single intervention for BRCA1 mutation carriers is PO at age 40, yielding a 15% absolute survival gain; for BRCA2 mutation carriers, the most effective single intervention is PM, yielding a 7% survival gain if performed at age 40 years. The combination of PM and PO at age 40 improves survival more than any single intervention, yielding 24% survival gain for BRCA1 and 11% for BRCA2 mutation carriers. PM at age 25 instead of age 40 offers minimal incremental benefit (1% to 2%); substituting screening for PM yields a similarly minimal decrement in survival (2% to 3%). Although PM at age 25 plus PO at age 40 years maximizes survival probability, substituting mammography plus MRI screening for PM seems to offer comparable survival. These results may guide women with BRCA1/2 mutations in their choices between prophylactic surgery and breast screening.

  8. Risk factors for dental caries in childhood: a five-year survival analysis.

    Science.gov (United States)

    Lee, Hyo-Jin; Kim, Jin-Bom; Jin, Bo-Hyoung; Paik, Dai-Il; Bae, Kwang-Hak

    2015-04-01

    The purpose of this study was to examine the risk factors of dental caries at the level of an individual person with survival analysis of the prospective data for 5 years. A total of 249 first-grade students participated in a follow-up study for 5 years. All participants responded to a questionnaire inquiring about socio-demographic variables and oral health behaviors. They also received an oral examination and were tested for Dentocult SM and LB. Over 5 years, the participants received yearly oral follow-up examinations to determine the incidence of dental caries. The incidence of one or more dental caries (DC1) and four or more dental caries (DC4) were defined as one or more and four or more decayed, missing, and filled permanent teeth increments, respectively. Socio-demographic variables, oral health behaviors, and status and caries activity tests were assessed as risk factors for DC1 and DC4. The adjusted hazard ratios (HRs) of risk factors for DC1 and DC4 were calculated using Cox proportional hazard regression models. During the 5-year follow-up period, DC1 and DC4 occurred in 87 and 25 participants, respectively. In multivariate hazard models, five or more decayed, missing, and filled primary molar teeth [HR 1.93, 95% confidence interval (CI) 1.19-3.13], and Dentocult LB of two or three (HR 2.21, 95% CI 1.37-3.56) were independent risk factors of DC1. For DC4, only Dentocult LB of two or three was an independent risk factor (HR 2.95, 95% CI 1.11-7.79). Our results suggest that dental caries incidence at an individual level can be associated with the experience of dental caries in primary teeth and Dentocult LB based on the survival models for the 5-year prospective data. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Arthritis and the Risk of Falling Into Poverty: A Survival Analysis Using Australian Data.

    Science.gov (United States)

    Callander, Emily J; Schofield, Deborah J

    2016-01-01

    Low income is known to be associated with having arthritis. However, no longitudinal studies have documented the relationship between developing arthritis and falling into poverty. The purpose of this study was to evaluate Australians who developed arthritis to determine if they had an elevated risk of falling into poverty. Survival analysis using Cox regression models was applied to nationally representative, longitudinal survey data obtained between January 1, 2007 and December 31, 2012 from Australian adults who were ages 21 years and older in 2007. The hazard ratio for falling into income poverty was 1.08 (95% confidence interval [95% CI] 1.06-1.09) in women who were diagnosed as having arthritis and 1.15 (95% CI 1.13-1.16) in men who were diagnosed as having arthritis, as compared to those who were never diagnosed as having arthritis. The hazard ratio for falling into multidimensional poverty was 1.15 (95% CI 1.14-1.17) in women who were diagnosed as having arthritis and 1.88 (95% CI 1.85-1.91) in men who were diagnosed as having arthritis. Developing arthritis increases the risk of falling into income poverty and multidimensional poverty. The risk of multidimensional poverty is greater than the risk of income poverty. Given the high prevalence of arthritis, the condition is likely an overlooked driver of poverty. © 2016, American College of Rheumatology.

  10. Pediatric differentiated thyroid carcinoma in stage I: risk factor analysis for disease free survival

    International Nuclear Information System (INIS)

    Wada, Nobuyuki; Rino, Yasushi; Masuda, Munetaka; Ito, Koichi; Sugino, Kiminori; Mimura, Takashi; Nagahama, Mitsuji; Kitagawa, Wataru; Shibuya, Hiroshi; Ohkuwa, Keiko; Nakayama, Hirotaka; Hirakawa, Shohei

    2009-01-01

    To examine the outcomes and risk factors in pediatric differentiated thyroid carcinoma (DTC) patients who were defined as TNM stage I because some patients develop disease recurrence but treatment strategy for such stage I pediatric patients is still controversial. We reviewed 57 consecutive TNM stage I patients (15 years or less) with DTC (46 papillary and 11 follicular) who underwent initial treatment at Ito Hospital between 1962 and 2004 (7 males and 50 females; mean age: 13.1 years; mean follow-up: 17.4 years). Clinicopathological results were evaluated in all patients. Multivariate analysis was performed to reveal the risk factors for disease-free survival (DFS) in these 57 patients. Extrathyroid extension and clinical lymphadenopathy at diagnosis were found in 7 and 12 patients, respectively. Subtotal/total thyroidectomy was performed in 23 patients, modified neck dissection in 38, and radioactive iodine therapy in 10. Pathological node metastasis was confirmed in 37 patients (64.9%). Fifteen patients (26.3%) exhibited local recurrence and 3 of them also developed metachronous lung metastasis. Ten of these 15 achieved disease-free after further treatments and no patients died of disease. In multivariate analysis, male gender (p = 0.017), advanced tumor (T3, 4a) stage (p = 0.029), and clinical lymphadenopathy (p = 0.006) were risk factors for DFS in stage I pediatric patients. Male gender, tumor stage, and lymphadenopathy are risk factors for DFS in stage I pediatric DTC patients. Aggressive treatment (total thyroidectomy, node dissection, and RI therapy) is considered appropriate for patients with risk factors, whereas conservative or stepwise approach may be acceptable for other patients

  11. The risk of falling into poverty after developing heart disease: a survival analysis.

    Science.gov (United States)

    Callander, Emily J; Schofield, Deborah J

    2016-07-15

    Those with a low income are known to have a higher risk of developing heart disease. However, the inverse relationship - falling into income poverty after developing heart disease has not been explored with longitudinal data. This paper aims to determine if those with heart disease have an elevated risk of falling into poverty. Survival analysis was conducted using the longitudinal Household Income and Labour Dynamics in Australia survey, between the years 2007 and 2012. The study focused on the Australian population aged 21 years and over in 2007 who were not already in poverty and did not already have heart disease, who were followed from 2007 to 2012. Cox regression models adjusting for age, sex and time-varying co-variates (marital status, home ownership and remoteness of area of residence) were constructed to assess the risk of falling into poverty. For those aged 20 who developed heart disease, the hazard ratio for falling into income poverty was 9.24 (95 % CI: 8.97-9.51) and for falling into multidimensional poverty the hazard ratio was 14.21 (95 % CI: 13.76-14.68); for those aged 40 the hazard ratio for falling into income poverty was 3.45 (95 % CI: 3.39-3.51) and for multidimensional poverty, 5.20 (95 % CI: 5.11-5.29); and for those aged 60 the hazard ratio for falling into income poverty was 1.29 (95 % CI: 1.28-1.30) and for multidimensional poverty, 1.52 (95 % CI: 1.51-1.54), relative those who never developed heart disease. The risk for both income and multidimensional poverty decreases with age up to the age of 70, over which, those who developed heart disease had a reduced risk of poverty. For those under the age of 70, developing heart disease is associated with an increased risk of falling into both income poverty and multidimensional poverty.

  12. Estimating the concordance probability in a survival analysis with a discrete number of risk groups.

    Science.gov (United States)

    Heller, Glenn; Mo, Qianxing

    2016-04-01

    A clinical risk classification system is an important component of a treatment decision algorithm. A measure used to assess the strength of a risk classification system is discrimination, and when the outcome is survival time, the most commonly applied global measure of discrimination is the concordance probability. The concordance probability represents the pairwise probability of lower patient risk given longer survival time. The c-index and the concordance probability estimate have been used to estimate the concordance probability when patient-specific risk scores are continuous. In the current paper, the concordance probability estimate and an inverse probability censoring weighted c-index are modified to account for discrete risk scores. Simulations are generated to assess the finite sample properties of the concordance probability estimate and the weighted c-index. An application of these measures of discriminatory power to a metastatic prostate cancer risk classification system is examined.

  13. A nonparametric approach to medical survival data: Uncertainty in the context of risk in mortality analysis

    International Nuclear Information System (INIS)

    Janurová, Kateřina; Briš, Radim

    2014-01-01

    Medical survival right-censored data of about 850 patients are evaluated to analyze the uncertainty related to the risk of mortality on one hand and compare two basic surgery techniques in the context of risk of mortality on the other hand. Colorectal data come from patients who underwent colectomy in the University Hospital of Ostrava. Two basic surgery operating techniques are used for the colectomy: either traditional (open) or minimally invasive (laparoscopic). Basic question arising at the colectomy operation is, which type of operation to choose to guarantee longer overall survival time. Two non-parametric approaches have been used to quantify probability of mortality with uncertainties. In fact, complement of the probability to one, i.e. survival function with corresponding confidence levels is calculated and evaluated. First approach considers standard nonparametric estimators resulting from both the Kaplan–Meier estimator of survival function in connection with Greenwood's formula and the Nelson–Aalen estimator of cumulative hazard function including confidence interval for survival function as well. The second innovative approach, represented by Nonparametric Predictive Inference (NPI), uses lower and upper probabilities for quantifying uncertainty and provides a model of predictive survival function instead of the population survival function. The traditional log-rank test on one hand and the nonparametric predictive comparison of two groups of lifetime data on the other hand have been compared to evaluate risk of mortality in the context of mentioned surgery techniques. The size of the difference between two groups of lifetime data has been considered and analyzed as well. Both nonparametric approaches led to the same conclusion, that the minimally invasive operating technique guarantees the patient significantly longer survival time in comparison with the traditional operating technique

  14. Statistical Analysis of Competing Risks: Overall Survival in a Group of Chronic Myeloid Leukemia Patients

    Czech Academy of Sciences Publication Activity Database

    Fürstová, Jana; Valenta, Zdeněk

    2011-01-01

    Roč. 7, č. 1 (2011), s. 2-10 ISSN 1801-5603 Institutional research plan: CEZ:AV0Z10300504 Keywords : competing risks * chronic myeloid leukemia (CML) * overall survival * cause-specific hazard * cumulative incidence function Subject RIV: IN - Informatics, Computer Science http://www.ejbi.eu/images/2011-1/Furstova_en.pdf

  15. Impact of Interstitial Pneumonia on the Survival and Risk Factors Analysis of Patients with Hematological Malignancy

    Directory of Open Access Journals (Sweden)

    Wei-Liang Chen

    2013-01-01

    Full Text Available Background. The emergence of interstitial pneumonia (IP in patients with hematological malignancy (HM is becoming a challenging scenario in current practice. However, detailed characterization and investigation of outcomes and risk factors on survival have not been addressed. Methods. We conducted a retrospective study of 42,584 cancer patients covering the period between 1996 and 2008 using the institutional cancer registry system. Among 816 HM patients, 61 patients with IP were recognized. The clinical features, laboratory results, and histological types were studied to determine the impact of IP on survival and identify the profile of prognostic factors. Results. HM patients with IP showed a significant worse survival than those without IP in the 5-year overall survival (P=0.027. The overall survival showed no significant difference between infectious pneumonia and noninfectious interstitial pneumonia (IIP versus nIIP (P=0.323. In a multivariate Cox regression model, leukocyte and platelet count were associated with increased risk of death. Conclusions. The occurrence of IP in HM patients is associated with increased mortality. Of interest, nIIP is a prognostic indicator in patients with lymphoma but not in patients with leukemia. However, aggressive management of IP in patients with HM is strongly advised, and further prospective survey is warranted.

  16. Incidence of cardiovascular events and associated risk factors in kidney transplant patients: a competing risks survival analysis.

    Science.gov (United States)

    Seoane-Pillado, María Teresa; Pita-Fernández, Salvador; Valdés-Cañedo, Francisco; Seijo-Bestilleiro, Rocio; Pértega-Díaz, Sonia; Fernández-Rivera, Constantino; Alonso-Hernández, Ángel; González-Martín, Cristina; Balboa-Barreiro, Vanesa

    2017-03-07

    The high prevalence of cardiovascular risk factors among the renal transplant population accounts for increased mortality. The aim of this study is to determine the incidence of cardiovascular events and factors associated with cardiovascular events in these patients. An observational ambispective follow-up study of renal transplant recipients (n = 2029) in the health district of A Coruña (Spain) during the period 1981-2011 was completed. Competing risk survival analysis methods were applied to estimate the cumulative incidence of developing cardiovascular events over time and to identify which characteristics were associated with the risk of these events. Post-transplant cardiovascular events are defined as the presence of myocardial infarction, invasive coronary artery therapy, cerebral vascular events, new-onset angina, congestive heart failure, rhythm disturbances, peripheral vascular disease and cardiovascular disease and death. The cause of death was identified through the medical history and death certificate using ICD9 (390-459, except: 427.5, 435, 446, 459.0). The mean age of patients at the time of transplantation was 47.0 ± 14.2 years; 62% were male. 16.5% had suffered some cardiovascular disease prior to transplantation and 9.7% had suffered a cardiovascular event. The mean follow-up period for the patients with cardiovascular event was 3.5 ± 4.3 years. Applying competing risk methodology, it was observed that the accumulated incidence of the event was 5.0% one year after transplantation, 8.1% after five years, and 11.9% after ten years. After applying multivariate models, the variables with an independent effect for predicting cardiovascular events are: male sex, age of recipient, previous cardiovascular disorders, pre-transplant smoking and post-transplant diabetes. This study makes it possible to determine in kidney transplant patients, taking into account competitive events, the incidence of post-transplant cardiovascular events and

  17. Survival analysis of factors affecting incidence risk of Salmonella Dublin in Danish dairy herds during a 7-year surveillance period

    DEFF Research Database (Denmark)

    Nielsen, Liza Rosenbaum; Dohoo, Ian

    2012-01-01

    , proportional hazard model allowing for recurrence within herds. During October to December the hazard of failures was higher (hazard ratio HR=3.4, P=0.0005) than the rest of the year. Accounting for the delay in bulk-tank milk antibody responses to S. Dublin infection, this indicates that introduction......-quarters (YQs), either at the start of the study period or after recovery from infection. Survival analysis was performed on a dataset including 6931 dairy herds with 118969 YQs at risk, in which 1523 failures (new infection events) occurred. Predictors obtained from register data were tested in a multivariable...

  18. Treatment of primary liver tumors with Yttrium-90 microspheres (TheraSphere) in high risk patients: analysis of survival and toxicities.

    Science.gov (United States)

    Reardon, Kelli A; McIntosh, Alyson F; Shilling, A Tanner; Hagspiel, Klaus D; Al-Osaimi, Abdullah; Berg, Carl; Caldwell, Stephen H; Northup, Patrick G; Angle, Fritz; Mulder, Robert; Rich, Tyvin A

    2009-02-01

    This retrospective study was undertaken to obtain information regarding the survival and toxicities after Yttrium-90 microspheres treatment in patients with primary liver malignancies. Baseline, treatment, and follow-up data were collected and analyzed for 21 patients treated with Yttrium-90 microspheres. Survival analysis was then performed. The results of this study showed that median survival for all the patients was 120 days. Twenty of 21 patients were categorized as high-risk with a median survival of 114 days. It was also found that one high-risk patient has survived 858 days with no recurrence of disease. Acute grade 3-5 toxicities were recorded for nine patients and consisted of elevations in AST and bilirubin, thrombocytopenia, abdominal pain, ascites, nausea, fatigue, and death. This study concluded that Yttrium-90 is a low-toxicity, outpatient alternative for individuals with liver cancer and without many options. The maximal value, however, may lie in the treatment of low-risk patients.

  19. Survival analysis models and applications

    CERN Document Server

    Liu, Xian

    2012-01-01

    Survival analysis concerns sequential occurrences of events governed by probabilistic laws.  Recent decades have witnessed many applications of survival analysis in various disciplines. This book introduces both classic survival models and theories along with newly developed techniques. Readers will learn how to perform analysis of survival data by following numerous empirical illustrations in SAS. Survival Analysis: Models and Applications: Presents basic techniques before leading onto some of the most advanced topics in survival analysis.Assumes only a minimal knowledge of SAS whilst enablin

  20. Evaluation of portfolio credit risk based on survival analysis for progressive censored data

    Science.gov (United States)

    Jaber, Jamil J.; Ismail, Noriszura; Ramli, Siti Norafidah Mohd

    2017-04-01

    In credit risk management, the Basel committee provides a choice of three approaches to the financial institutions for calculating the required capital: the standardized approach, the Internal Ratings-Based (IRB) approach, and the Advanced IRB approach. The IRB approach is usually preferred compared to the standard approach due to its higher accuracy and lower capital charges. This paper use several parametric models (Exponential, log-normal, Gamma, Weibull, Log-logistic, Gompertz) to evaluate the credit risk of the corporate portfolio in the Jordanian banks based on the monthly sample collected from January 2010 to December 2015. The best model is selected using several goodness-of-fit criteria (MSE, AIC, BIC). The results indicate that the Gompertz distribution is the best model parametric model for the data.

  1. Applied survival analysis using R

    CERN Document Server

    Moore, Dirk F

    2016-01-01

    Applied Survival Analysis Using R covers the main principles of survival analysis, gives examples of how it is applied, and teaches how to put those principles to use to analyze data using R as a vehicle. Survival data, where the primary outcome is time to a specific event, arise in many areas of biomedical research, including clinical trials, epidemiological studies, and studies of animals. Many survival methods are extensions of techniques used in linear regression and categorical data, while other aspects of this field are unique to survival data. This text employs numerous actual examples to illustrate survival curve estimation, comparison of survivals of different groups, proper accounting for censoring and truncation, model variable selection, and residual analysis. Because explaining survival analysis requires more advanced mathematics than many other statistical topics, this book is organized with basic concepts and most frequently used procedures covered in earlier chapters, with more advanced topics...

  2. Maternal Risk Factors for Singleton Preterm Births and Survival at ...

    African Journals Online (AJOL)

    Context: Risk factors for and survival of singleton preterm births may vary ... factors and survival‑to‑discharge rate for singleton preterm births at the University of ... Statistical analysis involved descriptive and inferential statistics at 95% level of ...

  3. Brachytherapy Improves Biochemical Failure–Free Survival in Low- and Intermediate-Risk Prostate Cancer Compared With Conventionally Fractionated External Beam Radiation Therapy: A Propensity Score Matched Analysis

    International Nuclear Information System (INIS)

    Smith, Graham D.; Pickles, Tom; Crook, Juanita; Martin, Andre-Guy; Vigneault, Eric; Cury, Fabio L.; Morris, Jim; Catton, Charles; Lukka, Himu; Warner, Andrew; Yang, Ying; Rodrigues, George

    2015-01-01

    Purpose: To compare, in a retrospective study, biochemical failure-free survival (bFFS) and overall survival (OS) in low-risk and intermediate-risk prostate cancer patients who received brachytherapy (BT) (either low-dose-rate brachytherapy [LDR-BT] or high-dose-rate brachytherapy with external beam radiation therapy [HDR-BT+EBRT]) versus external beam radiation therapy (EBRT) alone. Methods and Materials: Patient data were obtained from the ProCaRS database, which contains 7974 prostate cancer patients treated with primary radiation therapy at four Canadian cancer institutions from 1994 to 2010. Propensity score matching was used to obtain the following 3 matched cohorts with balanced baseline prognostic factors: (1) low-risk LDR-BT versus EBRT; (2) intermediate-risk LDR-BT versus EBRT; and (3) intermediate-risk HDR-BT+EBRT versus EBRT. Kaplan-Meier survival analysis was performed to compare differences in bFFS (primary endpoint) and OS in the 3 matched groups. Results: Propensity score matching created acceptable balance in the baseline prognostic factors in all matches. Final matches included 2 1:1 matches in the intermediate-risk cohorts, LDR-BT versus EBRT (total n=254) and HDR-BT+EBRT versus EBRT (total n=388), and one 4:1 match in the low-risk cohort (LDR-BT:EBRT, total n=400). Median follow-up ranged from 2.7 to 7.3 years for the 3 matched cohorts. Kaplan-Meier survival analysis showed that all BT treatment options were associated with statistically significant improvements in bFFS when compared with EBRT in all cohorts (intermediate-risk EBRT vs LDR-BT hazard ratio [HR] 4.58, P=.001; intermediate-risk EBRT vs HDR-BT+EBRT HR 2.08, P=.007; low-risk EBRT vs LDR-BT HR 2.90, P=.004). No significant difference in OS was found in all comparisons (intermediate-risk EBRT vs LDR-BT HR 1.27, P=.687; intermediate-risk EBRT vs HDR-BT+EBRT HR 1.55, P=.470; low-risk LDR-BT vs EBRT HR 1.41, P=.500). Conclusions: Propensity score matched analysis showed that BT options led

  4. ["That flesh, pink and perishable": analysis of disease-free survival analysis in breast cancer in Gipuzkoa (Spain) in the presence of competing risks].

    Science.gov (United States)

    Martínez-Camblor, Pablo; Larrañaga, Nerea; Sarasqueta, Cristina; Mitxelena, María José; Basterretxea, Mikel

    2009-01-01

    To analyze time of disease-free survival and relative survival in women diagnosed with breast cancer in the province of Gipuzkoa within the context of competing risks by assessing differences between the direct use of the Kaplan-Meier estimator and the multiple decrement method on the one hand, and relative survival on the other. All registered breast cancer cases in Gipuzkoa in 1995 and 1996 with stages other than stage IV were included. An 8-year follow-up for recurrence and a 10-year follow-up for survival were performed. Time of disease-free survival was studied by the multiple decrement model. Observed survival and survival corrected by the expected mortality in the population (relative survival) were also studied. Estimation of the probability of recurrence at 8 years with the multiple decrement method was 8.8% lower than that obtained with the Kaplan-Meier method. The difference between the observed and relative survival rates at 10 years was 10.8%. Both results show how, in this case, the Kaplan-Meier estimator overestimates both the probability of recurrence and that of mortality from the disease. Two issues are often overlooked when performing survival analyses: firstly, because of the lack of independence between survival time and censoring time, the results obtained by the Kaplan-Meier estimator are uninterpretable; secondly, it is an incontrovertible fact that one way or another, everyone causes failures. In this approach, survival analyses must take into account the probability of failure in the general population of reference. The results obtained in this study show that superficial use of the Kaplan Meier estimator overestimates both the probability of recurrence and that of mortality caused by the disease.

  5. Análisis de supervivencia en presencia de riesgos competitivos: estimadores de la probabilidad de suceso Survival analysis with competing risks: estimating failure probability

    Directory of Open Access Journals (Sweden)

    Javier Llorca

    2004-10-01

    Full Text Available Objetivo: Mostrar el efecto de los riesgos competitivos de muerte en el análisis de supervivencia. Métodos: Se presenta un ejemplo sobre la supervivencia libre de rechazo tras un trasplante cardíaco, en el que la muerte antes de desarrollar el rechazo actúa como riesgo competitivo. Mediante una simulación se comparan el estimador de Kaplan-Meier y el modelo de decrementos múltiples. Resultados: El método de Kaplan-Meier sobrestima el riesgo de rechazo. A continuación, se expone la aplicación del modelo de decrementos múltiples para el análisis de acontecimientos secundarios (en el ejemplo, la muerte tras el rechazo. Finalmente, se discuten las asunciones propias del método de Kaplan-Meier y las razones por las que no puede ser aplicado en presencia de riesgos competitivos. Conclusiones: El análisis de supervivencia debe ajustarse por los riesgos competitivos de muerte para evitar la sobrestimación del riesgo de fallo que se produce con el método de Kaplan-Meier.Objective: To show the impact of competing risks of death on survival analysis. Method: We provide an example of survival time without chronic rejection after heart transplantation, where death before rejection acts as a competing risk. Using a computer simulation, we compare the Kaplan-Meier estimator and the multiple decrement model. Results: The Kaplan-Meier method overestimated the probability of rejection. Next, we illustrate the use of the multiple decrement model to analyze secondary end points (in our example: death after rejection. Finally, we discuss Kaplan-Meier assumptions and why they fail in the presence of competing risks. Conclusions: Survival analysis should be adjusted for competing risks of death to avoid overestimation of the risk of rejection produced with the Kaplan-Meier method.

  6. Kaplan-Meier survival analysis overestimates cumulative incidence of health-related events in competing risk settings: a meta-analysis.

    Science.gov (United States)

    Lacny, Sarah; Wilson, Todd; Clement, Fiona; Roberts, Derek J; Faris, Peter; Ghali, William A; Marshall, Deborah A

    2018-01-01

    Kaplan-Meier survival analysis overestimates cumulative incidence in competing risks (CRs) settings. The extent of overestimation (or its clinical significance) has been questioned, and CRs methods are infrequently used. This meta-analysis compares the Kaplan-Meier method to the cumulative incidence function (CIF), a CRs method. We searched MEDLINE, EMBASE, BIOSIS Previews, Web of Science (1992-2016), and article bibliographies for studies estimating cumulative incidence using the Kaplan-Meier method and CIF. For studies with sufficient data, we calculated pooled risk ratios (RRs) comparing Kaplan-Meier and CIF estimates using DerSimonian and Laird random effects models. We performed stratified meta-analyses by clinical area, rate of CRs (CRs/events of interest), and follow-up time. Of 2,192 identified abstracts, we included 77 studies in the systematic review and meta-analyzed 55. The pooled RR demonstrated the Kaplan-Meier estimate was 1.41 [95% confidence interval (CI): 1.36, 1.47] times higher than the CIF. Overestimation was highest among studies with high rates of CRs [RR = 2.36 (95% CI: 1.79, 3.12)], studies related to hepatology [RR = 2.60 (95% CI: 2.12, 3.19)], and obstetrics and gynecology [RR = 1.84 (95% CI: 1.52, 2.23)]. The Kaplan-Meier method overestimated the cumulative incidence across 10 clinical areas. Using CRs methods will ensure accurate results inform clinical and policy decisions. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Neyman, Markov processes and survival analysis.

    Science.gov (United States)

    Yang, Grace

    2013-07-01

    J. Neyman used stochastic processes extensively in his applied work. One example is the Fix and Neyman (F-N) competing risks model (1951) that uses finite homogeneous Markov processes to analyse clinical trials with breast cancer patients. We revisit the F-N model, and compare it with the Kaplan-Meier (K-M) formulation for right censored data. The comparison offers a way to generalize the K-M formulation to include risks of recovery and relapses in the calculation of a patient's survival probability. The generalization is to extend the F-N model to a nonhomogeneous Markov process. Closed-form solutions of the survival probability are available in special cases of the nonhomogeneous processes, like the popular multiple decrement model (including the K-M model) and Chiang's staging model, but these models do not consider recovery and relapses while the F-N model does. An analysis of sero-epidemiology current status data with recurrent events is illustrated. Fix and Neyman used Neyman's RBAN (regular best asymptotic normal) estimates for the risks, and provided a numerical example showing the importance of considering both the survival probability and the length of time of a patient living a normal life in the evaluation of clinical trials. The said extension would result in a complicated model and it is unlikely to find analytical closed-form solutions for survival analysis. With ever increasing computing power, numerical methods offer a viable way of investigating the problem.

  8. Additive interaction in survival analysis

    DEFF Research Database (Denmark)

    Rod, Naja Hulvej; Lange, Theis; Andersen, Ingelise

    2012-01-01

    It is a widely held belief in public health and clinical decision-making that interventions or preventive strategies should be aimed at patients or population subgroups where most cases could potentially be prevented. To identify such subgroups, deviation from additivity of absolute effects...... an empirical example of interaction between education and smoking on risk of lung cancer. We argue that deviations from additivity of effects are important for public health interventions and clinical decision-making, and such estimations should be encouraged in prospective studies on health. A detailed...... is the relevant measure of interest. Multiplicative survival models, such as the Cox proportional hazards model, are often used to estimate the association between exposure and risk of disease in prospective studies. In Cox models, deviations from additivity have usually been assessed by surrogate measures...

  9. Biostatistics series module 9: Survival analysis

    Directory of Open Access Journals (Sweden)

    Avijit Hazra

    2017-01-01

    Full Text Available Survival analysis is concerned with “time to event“ data. Conventionally, it dealt with cancer death as the event in question, but it can handle any event occurring over a time frame, and this need not be always adverse in nature. When the outcome of a study is the time to an event, it is often not possible to wait until the event in question has happened to all the subjects, for example, until all are dead. In addition, subjects may leave the study prematurely. Such situations lead to what is called censored observations as complete information is not available for these subjects. The data set is thus an assemblage of times to the event in question and times after which no more information on the individual is available. Survival analysis methods are the only techniques capable of handling censored observations without treating them as missing data. They also make no assumption regarding normal distribution of time to event data. Descriptive methods for exploring survival times in a sample include life table and Kaplan–Meier techniques as well as various kinds of distribution fitting as advanced modeling techniques. The Kaplan–Meier cumulative survival probability over time plot has become the signature plot for biomedical survival analysis. Several techniques are available for comparing the survival experience in two or more groups – the log-rank test is popularly used. This test can also be used to produce an odds ratio as an estimate of risk of the event in the test group; this is called hazard ratio (HR. Limitations of the traditional log-rank test have led to various modifications and enhancements. Finally, survival analysis offers different regression models for estimating the impact of multiple predictors on survival. Cox's proportional hazard model is the most general of the regression methods that allows the hazard function to be modeled on a set of explanatory variables without making restrictive assumptions concerning the

  10. Urease activity as a risk factor for caries development in children during a three-year study period: a survival analysis approach

    Science.gov (United States)

    Morou-Bermudez, E; Elias-Boneta, A; Billings, RJ; Burne, RA; Garcia-Rivas, V; Brignoni-Nazario, V; Suárez-Pérez, E

    2011-01-01

    Recent cross-sectional studies suggest that reduced ability to generate alkali via the urease pathway in dental plaque may be an important caries risk factor, but it has not been assessed prospectively. OBJECTIVE To evaluate the effect of plaque and saliva urease activity on the risk for developing new caries over a three-year period in children. METHODS A panel of 80 children, three to six years of age at recruitment, was followed prospectively for three years. Plaque urease activity, saliva urease activity and dental caries were measured every six months. Survival analysis methodology was used to evaluate the effect of urease on caries development during the study period adjusted for gender, age, baseline caries levels, sugar consumption, amount of plaque, and mutans streptococci levels. RESULTS The risk for developing new caries increased in a dose-responsive manner with increasing levels of urease activity in saliva (adjusted HRQ4 vs. Q1: 4.98; 95%CI: 1.33, 18.69) and with decreasing urease activity in plaque (adjusted HRQ4 vs. Q1: 0.29; 95%CI: 0.11, 0.76). Multiple measurements of urease activity were conducted to overcome the variability of urease activity in this study. Baseline caries and mutans streptococci in saliva were also important predictors of caries risk. CONCLUSIONS Increased urease activity in saliva can be an indicator of increased caries risk in children, while increased urease activity in plaque may be associated with reduced caries risk. The reproducibility of urease measurements must be improved before these findings can be further tested and clinically applied. PMID:21784411

  11. High-dose chemotherapy for patients with high-risk breast cancer: a clinical and economic assessment using a quality-adjusted survival analysis.

    Science.gov (United States)

    Marino, Patricia; Roché, Henri; Moatti, Jean-Paul

    2008-04-01

    The benefit of high-dose chemotherapy (HDC) has not been clearly demonstrated. It may offer disease-free survival improvement at the expense of major toxicity and increasing cost. We evaluated the trade-offs between toxicity, relapse, and costs using a quality-adjusted time without symptoms or toxicity (Q-TWiST) analysis. The analysis was conducted in the context of a randomized trial (PEGASE 01) evaluating the benefit of HDC for 314 patients with high-risk breast cancer. A Q-TWiST analysis was first performed to compare HDC with standard chemotherapy. We then used the results of this Q-TWiST analysis to inform a cost per quality-adjusted life-year (QALY) comparison between treatments. Q-TWiST durations were in favor of HDC, whatever the weighting coefficients used for the analysis. This benefit was significant when the weighting coefficient related to the time spent after relapse was low (0.78), HDC offered no benefit. For intermediate values, the results depended on the weighting coefficient attributed to the toxicity period. The incremental cost per QALY ranged from 12,691euro/QALY to 26,439euro/QALY, according to the coefficients used to weight toxicity and relapse. The benefits of HDC outweigh the burdens of treatment for a wide range of utility coefficients. Economic impact is not a barrier to HDC diffusion in this situation. Nevertheless, no significant benefit was demonstrated for a certain range of utility values.

  12. Risk analysis

    International Nuclear Information System (INIS)

    Baron, J.H.; Nunez McLeod, J.; Rivera, S.S.

    1997-01-01

    This book contains a selection of research works performed in the CEDIAC Institute (Cuyo National University) in the area of Risk Analysis, with specific orientations to the subjects of uncertainty and sensitivity studies, software reliability, severe accident modeling, etc. This volume presents important material for all those researches who want to have an insight in the risk analysis field, as a tool to solution several problems frequently found in the engineering and applied sciences field, as well as for the academic teachers who want to keep up to date, including the new developments and improvements continuously arising in this field [es

  13. Hepatitis B and C Co-Infection in HIV Patients from the TREAT Asia HIV Observational Database: Analysis of Risk Factors and Survival

    Science.gov (United States)

    Chen, Marcelo; Wong, Wing-Wai; Law, Matthew G.; Kiertiburanakul, Sasisopin; Yunihastuti, Evy; Merati, Tuti Parwati; Lim, Poh Lian; Chaiwarith, Romanee; Phanuphak, Praphan; Lee, Man Po; Kumarasamy, Nagalingeswaran; Saphonn, Vonthanak; Ditangco, Rossana; Sim, Benedict L. H.; Nguyen, Kinh Van; Pujari, Sanjay; Kamarulzaman, Adeeba; Zhang, Fujie; Pham, Thuy Thanh; Choi, Jun Yong; Oka, Shinichi; Kantipong, Pacharee; Mustafa, Mahiran; Ratanasuwan, Winai; Durier, Nicolas; Chen, Yi-Ming Arthur

    2016-01-01

    Background We assessed the effects of hepatitis B (HBV) or hepatitis C (HCV) co-infection on outcomes of antiretroviral therapy (ART) in HIV-infected patients enrolled in the TREAT Asia HIV Observational Database (TAHOD), a multi-center cohort of HIV-infected patients in the Asia-Pacific region. Methods Patients testing HBs antigen (Ag) or HCV antibody (Ab) positive within enrollment into TAHOD were considered HBV or HCV co-infected. Factors associated with HBV and/or HCV co-infection were assessed by logistic regression models. Factors associated with post-ART HIV immunological response (CD4 change after six months) and virological response (HIV RNA <400 copies/ml after 12 months) were also determined. Survival was assessed by the Kaplan-Meier method and log rank test. Results A total of 7,455 subjects were recruited by December 2012. Of patients tested, 591/5656 (10.4%) were HBsAg positive, 794/5215 (15.2%) were HCVAb positive, and 88/4966 (1.8%) were positive for both markers. In multivariate analysis, HCV co-infection, age, route of HIV infection, baseline CD4 count, baseline HIV RNA, and HIV-1 subtype were associated with immunological recovery. Age, route of HIV infection, baseline CD4 count, baseline HIV RNA, ART regimen, prior ART and HIV-1 subtype, but not HBV or HCV co-infection, affected HIV RNA suppression. Risk factors affecting mortality included HCV co-infection, age, CDC stage, baseline CD4 count, baseline HIV RNA and prior mono/dual ART. Shortest survival was seen in subjects who were both HBV- and HCV-positive. Conclusion In this Asian cohort of HIV-infected patients, HCV co-infection, but not HBV co-infection, was associated with lower CD4 cell recovery after ART and increased mortality. PMID:26933963

  14. Volume of high-risk intratumoral subregions at multi-parametric MR imaging predicts overall survival and complements molecular analysis of glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Yi; Li, Ruijiang [Stanford University, Department of Radiation Oncology, Palo Alto, CA (United States); Hokkaido University, Global Station for Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido (Japan); Ren, Shangjie [Tianjin University, School of Electrical Engineering and Automation, Tianjin Shi (China); Tha, Khin Khin; Shirato, Hiroki [Hokkaido University, Global Station for Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido (Japan); Hokkaido University, Department of Radiology and Nuclear Medicine, Hokkaido (Japan); Wu, Jia [Stanford University, Department of Radiation Oncology, Palo Alto, CA (United States)

    2017-09-15

    To develop and validate a volume-based, quantitative imaging marker by integrating multi-parametric MR images for predicting glioblastoma survival, and to investigate its relationship and synergy with molecular characteristics. We retrospectively analysed 108 patients with primary glioblastoma. The discovery cohort consisted of 62 patients from the cancer genome atlas (TCGA). Another 46 patients comprising 30 from TCGA and 16 internally were used for independent validation. Based on integrated analyses of T1-weighted contrast-enhanced (T1-c) and diffusion-weighted MR images, we identified an intratumoral subregion with both high T1-c and low ADC, and accordingly defined a high-risk volume (HRV). We evaluated its prognostic value and biological significance with genomic data. On both discovery and validation cohorts, HRV predicted overall survival (OS) (concordance index: 0.642 and 0.653, P < 0.001 and P = 0.038, respectively). HRV stratified patients within the proneural molecular subtype (log-rank P = 0.040, hazard ratio = 2.787). We observed different OS among patients depending on their MGMT methylation status and HRV (log-rank P = 0.011). Patients with unmethylated MGMT and high HRV had significantly shorter survival (median survival: 9.3 vs. 18.4 months, log-rank P = 0.002). Volume of the high-risk intratumoral subregion identified on multi-parametric MRI predicts glioblastoma survival, and may provide complementary value to genomic information. (orig.)

  15. How do country risk and national cultural differences between partners affect the survival of international alliances in emerging countries? Longitudinal analysis of 165 international joint ventures in Brazil 1974 to 2005

    Directory of Open Access Journals (Sweden)

    Pierre-Xavier Meschi

    2007-06-01

    Full Text Available This article aims at identifying the individual and joint impact of two « country-level variables », namely national distance and country risk, on the survival of international joint ventures in emerging countries. Research hypotheses predicting the negative impact of national distance and country risk on survival are formulated in this article. These research hypotheses are tested in a sample of 165 international joint ventures that were formed in Brazil between 1974 and 2003. These joint ventures were subjected to an event history analysis over a period of time ranging from 1974 to 2005. The empirical results show that the intercultural dynamics increases the instability of international joint ventures whereas the survival of these alliances does not seem to be affected by the economic and political uncertainty of Brazil. Furthermore, the national distance between local and foreign partners has effects on survival that are variable according to the life cycle of international joint ventures.

  16. CASAS: Cancer Survival Analysis Suite, a web based application.

    Science.gov (United States)

    Rupji, Manali; Zhang, Xinyan; Kowalski, Jeanne

    2017-01-01

    We present CASAS, a shiny R based tool for interactive survival analysis and visualization of results. The tool provides a web-based one stop shop to perform the following types of survival analysis:  quantile, landmark and competing risks, in addition to standard survival analysis.  The interface makes it easy to perform such survival analyses and obtain results using the interactive Kaplan-Meier and cumulative incidence plots.  Univariate analysis can be performed on one or several user specified variable(s) simultaneously, the results of which are displayed in a single table that includes log rank p-values and hazard ratios along with their significance. For several quantile survival analyses from multiple cancer types, a single summary grid is constructed. The CASAS package has been implemented in R and is available via http://shinygispa.winship.emory.edu/CASAS/. The developmental repository is available at https://github.com/manalirupji/CASAS/.

  17. Survival analysis II: Cox regression

    NARCIS (Netherlands)

    Stel, Vianda S.; Dekker, Friedo W.; Tripepi, Giovanni; Zoccali, Carmine; Jager, Kitty J.

    2011-01-01

    In contrast to the Kaplan-Meier method, Cox proportional hazards regression can provide an effect estimate by quantifying the difference in survival between patient groups and can adjust for confounding effects of other variables. The purpose of this article is to explain the basic concepts of the

  18. Identifying Some Risk Factors for the Time to Death of the Elderly Using the Semi-Parametric Blended Model of Survival Analysis With Competing Risks

    Directory of Open Access Journals (Sweden)

    Samane Hajiabbasi

    2018-01-01

    Conclusion In single-variable fitting, age, history of myocardial infarction, history of stroke, and kidney problems were identified to have significant effects on the time to death of the elderly. Based on one-variable semi-parametric competing risk mixture fitted models, more significant risk factors for the time to death of elderly was identified when compared with a fitted multivariate mode to the data. This implies that the role of some independent variables can be explained by other independent variables.

  19. High risk bladder cancer: current management and survival

    Directory of Open Access Journals (Sweden)

    Anna M. Leliveld

    2011-04-01

    Full Text Available PURPOSE: To evaluate the pattern of care in patients with high risk non muscle invasive bladder cancer (NMIBC in the Comprehensive Cancer Center North-Netherlands (CCCN and to assess factors associated with the choice of treatment, recurrence and progression free survival rates. MATERIALS AND METHODS: Retrospective analysis of 412 patients with newly diagnosed high risk NMIBC. Clinical, demographic and follow-up data were obtained from the CCCN Cancer Registry and a detailed medical record review. Uni and multivariate analysis was performed to identify factors related to choice of treatment and 5 year recurrence and progression free survival. RESULTS: 74/412 (18% patients with high risk NMIBC underwent a transurethral resection (TUR as single treatment. Adjuvant treatment after TUR was performed in 90.7% of the patients treated in teaching hospitals versus 71.8 % in non-teaching hospitals (p 80 years OR 0.1 p = 0.001 and treatment in non-teaching hospitals (OR 0.25; p < 0.001 were associated with less adjuvant treatment after TUR. Tumor recurrence occurred in 191/392 (49% and progression in 84 /392 (21.4% patients. The mean 5-years progression free survival was 71.6% (95% CI 65.5-76.8. CONCLUSION: In this pattern of care study in high risk NMIBC, 18% of the patients were treated with TUR as single treatment. Age and treatment in non-teaching hospitals were associated with less adjuvant treatment after TUR. None of the variables sex, age, comorbidity, hospital type, stage and year of treatment was associated with 5 year recurrence or progression rates.

  20. Risk analysis

    International Nuclear Information System (INIS)

    Correa Lizarazu, X.

    2013-01-01

    The power point presentation Colombia risk evaluation experiences, sanitarian regulations evolution, chemical dangers food, biological dangers food, codex alimentarius, trade, industrial effects, dangers identification, data collection and risk profile

  1. Survival Analysis of Patients with End Stage Renal Disease

    Science.gov (United States)

    Urrutia, J. D.; Gayo, W. S.; Bautista, L. A.; Baccay, E. B.

    2015-06-01

    This paper provides a survival analysis of End Stage Renal Disease (ESRD) under Kaplan-Meier Estimates and Weibull Distribution. The data were obtained from the records of V. L. MakabaliMemorial Hospital with respect to time t (patient's age), covariates such as developed secondary disease (Pulmonary Congestion and Cardiovascular Disease), gender, and the event of interest: the death of ESRD patients. Survival and hazard rates were estimated using NCSS for Weibull Distribution and SPSS for Kaplan-Meier Estimates. These lead to the same conclusion that hazard rate increases and survival rate decreases of ESRD patient diagnosed with Pulmonary Congestion, Cardiovascular Disease and both diseases with respect to time. It also shows that female patients have a greater risk of death compared to males. The probability risk was given the equation R = 1 — e-H(t) where e-H(t) is the survival function, H(t) the cumulative hazard function which was created using Cox-Regression.

  2. Understanding survival analysis: Kaplan-Meier estimate.

    Science.gov (United States)

    Goel, Manish Kumar; Khanna, Pardeep; Kishore, Jugal

    2010-10-01

    Kaplan-Meier estimate is one of the best options to be used to measure the fraction of subjects living for a certain amount of time after treatment. In clinical trials or community trials, the effect of an intervention is assessed by measuring the number of subjects survived or saved after that intervention over a period of time. The time starting from a defined point to the occurrence of a given event, for example death is called as survival time and the analysis of group data as survival analysis. This can be affected by subjects under study that are uncooperative and refused to be remained in the study or when some of the subjects may not experience the event or death before the end of the study, although they would have experienced or died if observation continued, or we lose touch with them midway in the study. We label these situations as censored observations. The Kaplan-Meier estimate is the simplest way of computing the survival over time in spite of all these difficulties associated with subjects or situations. The survival curve can be created assuming various situations. It involves computing of probabilities of occurrence of event at a certain point of time and multiplying these successive probabilities by any earlier computed probabilities to get the final estimate. This can be calculated for two groups of subjects and also their statistical difference in the survivals. This can be used in Ayurveda research when they are comparing two drugs and looking for survival of subjects.

  3. SEMI-COMPETING RISKS ON A TRIVARIATE WEIBULL SURVIVAL MODEL

    Directory of Open Access Journals (Sweden)

    Jenq-Daw Lee

    2008-07-01

    Full Text Available A setting of a trivairate survival function using semi-competing risks concept is proposed, in which a terminal event can only occur after other events. The Stanford Heart Transplant data is reanalyzed using a trivariate Weibull distribution model with the proposed survival function.

  4. Five-Year Survival of 20,946 Unicondylar Knee Replacements and Patient Risk Factors for Failure: An Analysis of German Insurance Data.

    Science.gov (United States)

    Jeschke, Elke; Gehrke, Thorsten; Günster, Christian; Hassenpflug, Joachim; Malzahn, Jürgen; Niethard, Fritz Uwe; Schräder, Peter; Zacher, Josef; Halder, Andreas

    2016-10-19

    Improvements in implant design and surgical technique of unicondylar knee arthroplasty have led to reduced revision rates, but patient selection seems to be crucial for success of such arthroplasties. The purpose of the present study was to analyze the 5-year implant survival rate of unicondylar knee replacements in Germany and to identify patient factors associated with an increased risk of revision, including >30 comorbid conditions. Using nationwide billing data of the largest German health-care insurance for inpatient hospital treatment, we identified patients who underwent unicondylar knee arthroplasty between 2006 and 2012. Kaplan-Meier survival curves with revision as the end point and log-rank tests were used to evaluate 5-year implant survival. A multivariable Cox regression model was used to determine factors associated with revision. The risk factors of age, sex, diagnosis, comorbidities, type of implant fixation, and hospital volume were analyzed. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated. During the study period, a total of 20,946 unicondylar knee arthroplasties were included. The number of unicondylar knee arthroplasties per year increased during the study period from 2,527 in 2006 to 4,036 in 2012. The median patient age was 64 years (interquartile range, 56 to 72 years), and 60.4% of patients were female. During the time evaluated, the 1-year revision rate decreased from 14.3% in 2006 to 8.7% in 2011. The 5-year survival rate was 87.8% (95% CI, 87.3% to 88.3%). Significant risk factors (p 74 years was used as the reference); female sex (HR, 1.18 [95% CI, 1.07 to 1.29]); complicated diabetes (HR, 1.47 [95% CI, 1.03 to 2.12]); depression (HR, 1.29 [95% CI, 1.06 to 1.57]); obesity, defined as a body mass index of ≥30 kg/m 2 (HR, 1.13 [95% CI, 1.02 to 1.26]); and low-volume hospitals, denoted as an annual hospital volume of ≤10 cases (HR, 1.60 [95% CI, 1.39 to 1.84]), 11 to 20 cases (HR, 1.47 [95% CI, 1.27 to 1

  5. Superior metastasis-free survival for patients with high-risk prostate cancer treated with definitive radiation therapy compared to radical prostatectomy: A propensity score-matched analysis

    Directory of Open Access Journals (Sweden)

    Stephanie Markovina, MD, PhD

    2018-04-01

    Full Text Available Purpose: For high-risk prostate cancer (HR-PCa in men with a life expectancy of at least 10 years, the National Comprehensive Cancer Network recommends radiation therapy (RT plus androgen deprivation therapy (ADT with category 1 evidence or radical prostatectomy (RP as an acceptable initial therapy. Randomized evidence regarding which therapy is optimal for disease control is lacking for men with HR-PCa. We performed a propensity-score-matched comparison of outcomes for men with localized HR-PCa treated with primary RT or RP. Methods and materials: The medical records of patients with localized HR-PCa who were treated at our institution between 2002 and 2011 were reviewed. Patient and disease characteristics, treatment details, and outcomes were collected. A combination of nearest-neighbor propensity score matching on age, Adult Comorbidity Evaluation-27 comorbidity index, prostate-specific antigen, biopsy Gleason scores, and clinical T-stage as well as exact matching on prostate-specific antigen, biopsy Gleason scores, and clinical T-stage was performed. Outcomes were measured from diagnosis. Multivariate Cox proportional hazards regression was used to compare metastasis-free and overall survival. Results: A total of 246 patients were identified with 62 propensity-score-matched pairs. ADT was administered to 6.5% and 80.6% of patients receiving RP and RT, respectively. Five-year rates of metastasis for RP and RT were 33% and 8.9%, respectively (P = .003. Overall survival was not different. Delay of salvage therapy was longer for patients undergoing primary RT (P < .001. Findings were similar when only those patients who did not receive ADT were compared. Conclusions: At our institution, treatment with primary RT resulted in superior metastasis-free survival over RP. This was not accompanied by an improvement in OS.

  6. Enhanced secondary analysis of survival data: reconstructing the data from published Kaplan-Meier survival curves

    Directory of Open Access Journals (Sweden)

    Guyot Patricia

    2012-02-01

    Full Text Available Abstract Background The results of Randomized Controlled Trials (RCTs on time-to-event outcomes that are usually reported are median time to events and Cox Hazard Ratio. These do not constitute the sufficient statistics required for meta-analysis or cost-effectiveness analysis, and their use in secondary analyses requires strong assumptions that may not have been adequately tested. In order to enhance the quality of secondary data analyses, we propose a method which derives from the published Kaplan Meier survival curves a close approximation to the original individual patient time-to-event data from which they were generated. Methods We develop an algorithm that maps from digitised curves back to KM data by finding numerical solutions to the inverted KM equations, using where available information on number of events and numbers at risk. The reproducibility and accuracy of survival probabilities, median survival times and hazard ratios based on reconstructed KM data was assessed by comparing published statistics (survival probabilities, medians and hazard ratios with statistics based on repeated reconstructions by multiple observers. Results The validation exercise established there was no material systematic error and that there was a high degree of reproducibility for all statistics. Accuracy was excellent for survival probabilities and medians, for hazard ratios reasonable accuracy can only be obtained if at least numbers at risk or total number of events are reported. Conclusion The algorithm is a reliable tool for meta-analysis and cost-effectiveness analyses of RCTs reporting time-to-event data. It is recommended that all RCTs should report information on numbers at risk and total number of events alongside KM curves.

  7. Enhanced secondary analysis of survival data: reconstructing the data from published Kaplan-Meier survival curves.

    Science.gov (United States)

    Guyot, Patricia; Ades, A E; Ouwens, Mario J N M; Welton, Nicky J

    2012-02-01

    The results of Randomized Controlled Trials (RCTs) on time-to-event outcomes that are usually reported are median time to events and Cox Hazard Ratio. These do not constitute the sufficient statistics required for meta-analysis or cost-effectiveness analysis, and their use in secondary analyses requires strong assumptions that may not have been adequately tested. In order to enhance the quality of secondary data analyses, we propose a method which derives from the published Kaplan Meier survival curves a close approximation to the original individual patient time-to-event data from which they were generated. We develop an algorithm that maps from digitised curves back to KM data by finding numerical solutions to the inverted KM equations, using where available information on number of events and numbers at risk. The reproducibility and accuracy of survival probabilities, median survival times and hazard ratios based on reconstructed KM data was assessed by comparing published statistics (survival probabilities, medians and hazard ratios) with statistics based on repeated reconstructions by multiple observers. The validation exercise established there was no material systematic error and that there was a high degree of reproducibility for all statistics. Accuracy was excellent for survival probabilities and medians, for hazard ratios reasonable accuracy can only be obtained if at least numbers at risk or total number of events are reported. The algorithm is a reliable tool for meta-analysis and cost-effectiveness analyses of RCTs reporting time-to-event data. It is recommended that all RCTs should report information on numbers at risk and total number of events alongside KM curves.

  8. Random survival forests for competing risks

    DEFF Research Database (Denmark)

    Ishwaran, Hemant; Gerds, Thomas A; Kogalur, Udaya B

    2014-01-01

    We introduce a new approach to competing risks using random forests. Our method is fully non-parametric and can be used for selecting event-specific variables and for estimating the cumulative incidence function. We show that the method is highly effective for both prediction and variable selection...

  9. Risk factors and survival outcome for non-elective referral in non-small cell lung cancer patients--analysis based on the National Lung Cancer Audit.

    Science.gov (United States)

    Beckett, P; Tata, L J; Hubbard, R B

    2014-03-01

    Survival after diagnosis of lung cancer is poor and seemingly lower in the UK than other Western countries, due in large part to late presentation with advanced disease precluding curative treatment. Recent research suggests that around one-third of lung cancer patients reach specialist care after emergency presentation and have a worse survival outcome. Confirmation of these data and understanding which patients are affected may allow a targeted approach to improving outcomes. We used data from the UK National Lung Cancer Audit in a multivariate logistic regression model to quantify the association of non-elective referral in non-small cell lung cancer patients with covariates including age, sex, stage, performance status, co-morbidity and socioeconomic status and used the Kaplan-Meier method and Cox proportional hazards model to quantify survival by source of referral. In an analysis of 133,530 cases of NSCLC who presented 2006-2011, 19% of patients were referred non-electively (following an emergency admission to hospital or following an emergency presentation to A&E). This route of referral was strongly associated with more advanced disease stage (e.g. in Stage IV - OR: 2.34, 95% CI: 2.14-2.57, p<0.001) and worse performance status (e.g. in PS 4 - OR: 7.28, 95% CI: 6.75-7.86, p<0.001), but was also independently associated with worse socioeconomic status, and extremes of age. These patients were more likely to have died within 1 year of diagnosis (hazard ratio of 1.51 (95% CI: 1.49-1.54) after adjustment for key clinical variables. Our data confirm and quantify poorer survival in lung cancer patients who are referred non-electively to specialist care, which is more common in patients with poorer performance status, higher disease stage and less advantaged socioeconomic status. Work to tackle this late presentation should be urgently accelerated, since its realisation holds the promise of improved outcomes and better healthcare resource utilisation. Copyright

  10. Information security risk analysis

    CERN Document Server

    Peltier, Thomas R

    2001-01-01

    Effective Risk AnalysisQualitative Risk AnalysisValue AnalysisOther Qualitative MethodsFacilitated Risk Analysis Process (FRAP)Other Uses of Qualitative Risk AnalysisCase StudyAppendix A: QuestionnaireAppendix B: Facilitated Risk Analysis Process FormsAppendix C: Business Impact Analysis FormsAppendix D: Sample of ReportAppendix E: Threat DefinitionsAppendix F: Other Risk Analysis OpinionsIndex

  11. Survival in common cancers defined by risk and survival of family members

    Directory of Open Access Journals (Sweden)

    Jianguang Ji

    2011-10-01

    Full Text Available Studies on survival between familial and sporadic cancers have been inconclusive and only recent data on a limited number of cancers are available on the concordance of survival between family members. In this review, we address these questions by evaluating the published and unpublished data from the nation-wide Swedish Family-Cancer Database and a total of 13 cancer sites were assessed. Using sporadic cancer as reference, HRs were close to 1.0 for most of the familial cancers in both the offspring and parental generations, which suggested that survival in patients with familial and sporadic cancers was equal, with an exception for ovarian cancer with a worse prognosis. Compared to offspring whose parents had a poor survival, those with a good parental survival had a decreased risk of death for most cancers and HR was significantly decreased for cancers in the breast, prostate, bladder, and kidney. For colorectal and nervous system cancers, favorable survival between the generations showed a borderline significance. These data are consistent in showing that both good and poor survival in certain cancers aggregate in families. Genetic factors are likely to contribute to the results. These observations call for intensified efforts to consider heritability in survival as one mechanism regulating prognosis in cancer patients.

  12. SURVIVAL ANALYSIS AND LENGTH-BIASED SAMPLING

    Directory of Open Access Journals (Sweden)

    Masoud Asgharian

    2010-12-01

    Full Text Available When survival data are colleted as part of a prevalent cohort study, the recruited cases have already experienced their initiating event. These prevalent cases are then followed for a fixed period of time at the end of which the subjects will either have failed or have been censored. When interests lies in estimating the survival distribution, from onset, of subjects with the disease, one must take into account that the survival times of the cases in a prevalent cohort study are left truncated. When it is possible to assume that there has not been any epidemic of the disease over the past period of time that covers the onset times of the subjects, one may assume that the underlying incidence process that generates the initiating event times is a stationary Poisson process. Under such assumption, the survival times of the recruited subjects are called “lengthbiased”. I discuss the challenges one is faced with in analyzing these type of data. To address the theoretical aspects of the work, I present asymptotic results for the NPMLE of the length-biased as well as the unbiased survival distribution. I also discuss estimating the unbiased survival function using only the follow-up time. This addresses the case that the onset times are either unknown or known with uncertainty. Some of our most recent work and open questions will be presented. These include some aspects of analysis of covariates, strong approximation, functional LIL and density estimation under length-biased sampling with right censoring. The results will be illustrated with survival data from patients with dementia, collected as part of the Canadian Study of Health and Aging (CSHA.

  13. A taylor series approach to survival analysis

    International Nuclear Information System (INIS)

    Brodsky, J.B.; Groer, P.G.

    1984-09-01

    A method of survival analysis using hazard functions is developed. The method uses the well known mathematical theory for Taylor Series. Hypothesis tests of the adequacy of many statistical models, including proportional hazards and linear and/or quadratic dose responses, are obtained. A partial analysis of leukemia mortality in the Life Span Study cohort is used as an example. Furthermore, a relatively robust estimation procedure for the proportional hazards model is proposed. (author)

  14. Survival Function Analysis of Planet Size Distribution

    OpenAIRE

    Zeng, Li; Jacobsen, Stein B.; Sasselov, Dimitar D.; Vanderburg, Andrew

    2018-01-01

    Applying the survival function analysis to the planet radius distribution of the Kepler exoplanet candidates, we have identified two natural divisions of planet radius at 4 Earth radii and 10 Earth radii. These divisions place constraints on planet formation and interior structure model. The division at 4 Earth radii separates small exoplanets from large exoplanets above. When combined with the recently-discovered radius gap at 2 Earth radii, it supports the treatment of planets 2-4 Earth rad...

  15. Prognostic and survival analysis of presbyopia: The healthy twin study

    Science.gov (United States)

    Lira, Adiyani; Sung, Joohon

    2015-12-01

    Presbyopia, a vision condition in which the eye loses its flexibility to focus on near objects, is part of ageing process which mostly perceptible in the early or mid 40s. It is well known that age is its major risk factor, while sex, alcohol, poor nutrition, ocular and systemic diseases are known as common risk factors. However, many other variables might influence the prognosis. Therefore in this paper we developed a prognostic model to estimate survival from presbyopia. 1645 participants which part of the Healthy Twin Study, a prospective cohort study that has recruited Korean adult twins and their family members based on a nation-wide registry at public health agencies since 2005, were collected and analyzed by univariate analysis as well as Cox proportional hazard model to reveal the prognostic factors for presbyopia while survival curves were calculated by Kaplan-Meier method. Besides age, sex, diabetes, and myopia; the proposed model shows that education level (especially engineering program) also contribute to the occurrence of presbyopia as well. Generally, at 47 years old, the chance of getting presbyopia becomes higher with the survival probability is less than 50%. Furthermore, our study shows that by stratifying the survival curve, MZ has shorter survival with average onset time about 45.8 compare to DZ and siblings with 47.5 years old. By providing factors that have more effects and mainly associate with presbyopia, we expect that we could help to design an intervention to control or delay its onset time.

  16. Risk factors affecting survival in heart transplant patients.

    Science.gov (United States)

    Almenar, L; Cardo, M L; Martínez-Dolz, L; García-Palomar, C; Rueda, J; Zorio, E; Arnau, M A; Osa, A; Palencia, M

    2005-11-01

    Certain cardiovascular risk factors have been linked to morbidity and mortality in heart transplant (HT) patients. The sum of various risk factors may have a large cumulative negative effect, leading to a substantially worse prognosis and the need to consider whether HT is contraindicated. The objective of this study was to determine whether the risk factors usually available prior to HT result in an excess mortality in our setting that contraindicates transplantation. Consecutive patients who underwent heart transplantation from November 1987 to January 2004 were included. Heart-lung transplants, retransplants, and pediatric transplants were excluded. Of the 384 patients, 89% were men. Mean age was 52 years (range, 12 to 67). Underlying disease included ischemic heart disease (52%), idiopathic dilated cardiomyopathy (36%), valvular disease (8%), and other (4%). Variables considered risk factors were obesity (BMI >25), dyslipidemia, hypertension, prior thoracic surgery, diabetes, and history of ischemic heart disease. Survival curves by number of risk factors using Kaplan-Meier and log-rank for comparison of curves. Overall patient survival at 1, 5, 10, and 13 years was 76%, 68%, 54%, and 47%, respectively. Survival at 10 years, if fewer than two risk factors were present, was 69%; 59% if two or three factors were present; and 37% if more than three associated risk factors were present (P = .04). The presence of certain risk factors in patients undergoing HT resulted in lower survival rates. The combination of various risk factors clearly worsened outcomes. However, we do not believe this should be an absolute contraindication for transplantation.

  17. Regulatory activity based risk model identifies survival of stage II and III colorectal carcinoma.

    Science.gov (United States)

    Liu, Gang; Dong, Chuanpeng; Wang, Xing; Hou, Guojun; Zheng, Yu; Xu, Huilin; Zhan, Xiaohui; Liu, Lei

    2017-11-17

    Clinical and pathological indicators are inadequate for prognosis of stage II and III colorectal carcinoma (CRC). In this study, we utilized the activity of regulatory factors, univariate Cox regression and random forest for variable selection and developed a multivariate Cox model to predict the overall survival of Stage II/III colorectal carcinoma in GSE39582 datasets (469 samples). Patients in low-risk group showed a significant longer overall survival and recurrence-free survival time than those in high-risk group. This finding was further validated in five other independent datasets (GSE14333, GSE17536, GSE17537, GSE33113, and GSE37892). Besides, associations between clinicopathological information and risk score were analyzed. A nomogram including risk score was plotted to facilitate the utilization of risk score. The risk score model is also demonstrated to be effective on predicting both overall and recurrence-free survival of chemotherapy received patients. After performing Gene Set Enrichment Analysis (GSEA) between high and low risk groups, we found that several cell-cell interaction KEGG pathways were identified. Funnel plot results showed that there was no publication bias in these datasets. In summary, by utilizing the regulatory activity in stage II and III colorectal carcinoma, the risk score successfully predicts the survival of 1021 stage II/III CRC patients in six independent datasets.

  18. Causal inference in survival analysis using pseudo-observations.

    Science.gov (United States)

    Andersen, Per K; Syriopoulou, Elisavet; Parner, Erik T

    2017-07-30

    Causal inference for non-censored response variables, such as binary or quantitative outcomes, is often based on either (1) direct standardization ('G-formula') or (2) inverse probability of treatment assignment weights ('propensity score'). To do causal inference in survival analysis, one needs to address right-censoring, and often, special techniques are required for that purpose. We will show how censoring can be dealt with 'once and for all' by means of so-called pseudo-observations when doing causal inference in survival analysis. The pseudo-observations can be used as a replacement of the outcomes without censoring when applying 'standard' causal inference methods, such as (1) or (2) earlier. We study this idea for estimating the average causal effect of a binary treatment on the survival probability, the restricted mean lifetime, and the cumulative incidence in a competing risks situation. The methods will be illustrated in a small simulation study and via a study of patients with acute myeloid leukemia who received either myeloablative or non-myeloablative conditioning before allogeneic hematopoetic cell transplantation. We will estimate the average causal effect of the conditioning regime on outcomes such as the 3-year overall survival probability and the 3-year risk of chronic graft-versus-host disease. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  19. Individual survival curves comparing subjective and observed mortality risks.

    Science.gov (United States)

    Bissonnette, Luc; Hurd, Michael D; Michaud, Pierre-Carl

    2017-12-01

    We compare individual survival curves constructed from objective (actual mortality) and elicited subjective information (probability of survival to a given target age). We develop a methodology to estimate jointly subjective and objective individual survival curves accounting for rounding on subjective reports of perceived survival. We make use of the long follow-up period in the Health and Retirement Study and the high quality of mortality data to estimate individual survival curves that feature both observed and unobserved heterogeneity. This allows us to compare objective and subjective estimates of remaining life expectancy for various groups and compare welfare effects of objective and subjective mortality risk using the life cycle model of consumption. We find that subjective and objective hazards are not the same. The median welfare loss from misperceptions of mortality risk when annuities are not available is 7% of current wealth at age 65 whereas more than 25% of respondents have losses larger than 60% of wealth. When annuities are available and exogenously given, the welfare loss is substantially lower. Copyright © 2017 John Wiley & Sons, Ltd.

  20. Using Survival Analysis to Evaluate Medical Equipment Battery Life.

    Science.gov (United States)

    Kuhajda, David

    2016-01-01

    As hospital medical device managers obtain more data, opportunities exist for using the data to improve medical device management, enhance patient safety, and evaluate costs of decisions. As a demonstration of the ability to use data analytics, this article applies survival analysis statistical techniques to assist in making decisions on medical equipment maintenance. The analysis was performed on a large amount of data related to failures of an infusion pump manufacturer's lithium battery and two aftermarket replacement lithium batteries from one hospital facility. The survival analysis resulted in statistical evidence showing that one of the third-party batteries had a lower survival curve than the infusion pump manufacturer's battery. This lower survival curve translates to a shorter expected life before replacement is needed. The data suggested that to limit unexpected failures, replacing batteries at a two-year interval, rather than the current industry recommendation of three years, may be warranted. For less than $5,400 in additional annual cost, the risk of unexpected battery failures can be reduced from an estimated 28% to an estimated 7%.

  1. Anthropometric characteristics and ovarian cancer risk and survival.

    Science.gov (United States)

    Minlikeeva, Albina N; Moysich, Kirsten B; Mayor, Paul C; Etter, John L; Cannioto, Rikki A; Ness, Roberta B; Starbuck, Kristen; Edwards, Robert P; Segal, Brahm H; Lele, Sashikant; Odunsi, Kunle; Diergaarde, Brenda; Modugno, Francesmary

    2018-02-01

    Multiple studies have examined the role of anthropometric characteristics in ovarian cancer risk and survival; however, their results have been conflicting. We investigated the associations between weight change, height and height change and risk and outcome of ovarian cancer using data from a large population-based case-control study. Data from 699 ovarian cancer cases and 1,802 controls who participated in the HOPE study were included. We used unconditional logistic regression adjusted for age, race, number of pregnancies, use of oral contraceptives, and family history of breast or ovarian cancer to examine the associations between self-reported height and weight and height change with ovarian cancer risk. Cox proportional hazards regression models adjusted for age and stage were used to examine the association between the exposure variables and overall and progression-free survival among ovarian cancer cases. We observed an increased risk of ovarian cancer mortality and progression for gaining more than 20 pounds between ages 18-30, HR 1.36; 95% CI 1.05-1.76, and HR 1.31; 95% CI 1.04-1.66, respectively. Losing weight and gaining it back multiple times was inversely associated with both ovarian cancer risk, OR 0.78; 95% CI 0.63-0.97 for 1-4 times and OR 0.73; 95% CI 0.54-0.99 for 5-9 times, and mortality, HR 0.63; 95% CI 0.40-0.99 for 10-14 times. Finally, being taller during adolescence and adulthood was associated with increased risk of mortality. Taller stature and weight gain over lifetime were not related to ovarian cancer risk. Our results suggest that height and weight and their change over time may influence ovarian cancer risk and survival. These findings suggest that biological mechanisms underlying these associations may be hormone driven and may play an important role in relation to ovarian carcinogenesis and tumor progression.

  2. A retrospective analysis of the impact of treatments and blood counts on survival and the risk of vascular events during the course of polycythaemia vera

    DEFF Research Database (Denmark)

    Enblom-Larsson, Anneli; Girodon, Francois; Bak, Marie

    2017-01-01

    Vascular and non-vascular complications are common in patients with polycythaemia vera. This retrospective study of 217 patients with polycythaemia vera aimed to determine whether blood counts with respect to different treatments influenced the complication rate and survival. We found that 78 (36...

  3. Chronic kidney disease in dogs in UK veterinary practices: prevalence, risk factors, and survival.

    Science.gov (United States)

    O'Neill, D G; Elliott, J; Church, D B; McGreevy, P D; Thomson, P C; Brodbelt, D C

    2013-01-01

    The prevalence for chronic kidney disease (CKD) in dogs varies widely (0.05-3.74%). Identified risk factors include advancing age, specific breeds, small body size, and periodontal disease. To estimate the prevalence and identify risk factors associated with CKD diagnosis and survival in dogs. Purebred dogs were hypothesized to have higher CKD risk and poorer survival characteristics than crossbred dogs. A merged clinical database of 107,214 dogs attending 89 UK veterinary practices over a 2-year period (January 2010-December 2011). A longitudinal study design estimated the apparent prevalence (AP) whereas the true prevalence (TP) was estimated using Bayesian analysis. A nested case-control study design evaluated risk factors. Survival analysis used the Kaplan-Meier survival curve method and multivariable Cox proportional hazards regression modeling. The CKD AP was 0.21% (95% CI: 0.19-0.24%) and TP was 0.37% (95% posterior credibility interval 0.02-1.44%). Significant risk factors included increasing age, being insured, and certain breeds (Cocker Spaniel, Cavalier King Charles Spaniel). Cardiac disease was a significant comorbid disorder. Significant clinical signs included halitosis, weight loss, polyuria/polydipsia, urinary incontinence, vomiting, decreased appetite, lethargy, and diarrhea. The median survival time from diagnosis was 226 days (95% CI 112-326 days). International Renal Interest Society stage and blood urea nitrogen concentration at diagnosis were significantly associated with hazard of death due to CKD. Chronic kidney disease compromises dog welfare. Increased awareness of CKD risk factors and association of blood biochemistry results with survival time should facilitate diagnosis and optimize case management to improve animal survival and welfare. Copyright © 2013 by the American College of Veterinary Internal Medicine.

  4. Foundations of Risk Analysis

    CERN Document Server

    Aven, Terje

    2012-01-01

    Foundations of Risk Analysis presents the issues core to risk analysis - understanding what risk means, expressing risk, building risk models, addressing uncertainty, and applying probability models to real problems. The author provides the readers with the knowledge and basic thinking they require to successfully manage risk and uncertainty to support decision making. This updated edition reflects recent developments on risk and uncertainty concepts, representations and treatment. New material in Foundations of Risk Analysis includes:An up to date presentation of how to understand, define and

  5. Investigation on circular asymmetry of geographical distribution in cancer mortality of Hiroshima atomic bomb survivors based on risk maps: analysis of spatial survival data

    International Nuclear Information System (INIS)

    Tonda, Tetsuji; Satoh, Kenichi; Otani, Keiko; Ohtaki, Megu; Sato, Yuya; Maruyama, Hirofumi; Kawakami, Hideshi; Tashiro, Satoshi; Hoshi, Masaharu

    2012-01-01

    While there is a considerable number of studies on the relationship between the risk of disease or death and direct exposure from the atomic bomb in Hiroshima, the risk for indirect exposure caused by residual radioactivity has not yet been fully evaluated. One of the reasons is that risk assessments have utilized estimated radiation doses, but that it is difficult to estimate indirect exposure. To evaluate risks for other causes, including indirect radiation exposure, as well as direct exposure, a statistical method is described here that evaluates risk with respect to individual location at the time of atomic bomb exposure instead of radiation dose. In addition, it is also considered to split the risks into separate risks due to direct exposure and other causes using radiation dose. The proposed method is applied to a cohort study of Hiroshima atomic bomb survivors. The resultant contour map suggests that the region west to the hypocenter has a higher risk compared to other areas. This in turn suggests that there exists an impact on risk that cannot be explained by direct exposure. (orig.)

  6. Investigation on circular asymmetry of geographical distribution in cancer mortality of Hiroshima atomic bomb survivors based on risk maps: analysis of spatial survival data

    Energy Technology Data Exchange (ETDEWEB)

    Tonda, Tetsuji; Satoh, Kenichi; Otani, Keiko; Ohtaki, Megu [Hiroshima University, Department of Environmetrics and Biometrics, Research Institute for Radiation Biology and Medicine (Japan); Sato, Yuya [Hiroshima University, Division of Radiation Information Registry, Research Institute for Radiation Biology and Medicine (Japan); Maruyama, Hirofumi; Kawakami, Hideshi [Hiroshima University, Department of Epidemiology, Research Institute for Radiation Biology and Medicine (Japan); Tashiro, Satoshi [Hiroshima University, Division of Radiation Information Registry, Research Institute for Radiation Biology and Medicine (Japan); Hiroshima University, Department of Cellular Biology, Research Institute for Radiation Biology and Medicine (Japan); Hoshi, Masaharu [Hiroshima University, Department of Radiation Biophysics, Research Institute for Radiation Biology and Medicine (Japan)

    2012-05-15

    While there is a considerable number of studies on the relationship between the risk of disease or death and direct exposure from the atomic bomb in Hiroshima, the risk for indirect exposure caused by residual radioactivity has not yet been fully evaluated. One of the reasons is that risk assessments have utilized estimated radiation doses, but that it is difficult to estimate indirect exposure. To evaluate risks for other causes, including indirect radiation exposure, as well as direct exposure, a statistical method is described here that evaluates risk with respect to individual location at the time of atomic bomb exposure instead of radiation dose. In addition, it is also considered to split the risks into separate risks due to direct exposure and other causes using radiation dose. The proposed method is applied to a cohort study of Hiroshima atomic bomb survivors. The resultant contour map suggests that the region west to the hypocenter has a higher risk compared to other areas. This in turn suggests that there exists an impact on risk that cannot be explained by direct exposure. (orig.)

  7. When perception reflects reality: Non-native grass invasion alters small mammal risk landscapes and survival

    Science.gov (United States)

    Ceradnini, Joseph P.; Chalfoun, Anna

    2017-01-01

    Modification of habitat structure due to invasive plants can alter the risk landscape for wildlife by, for example, changing the quality or availability of refuge habitat. Whether perceived risk corresponds with actual fitness outcomes, however, remains an important open question. We simultaneously measured how habitat changes due to a common invasive grass (cheatgrass, Bromus tectorum) affected the perceived risk, habitat selection, and apparent survival of a small mammal, enabling us to assess how well perceived risk influenced important behaviors and reflected actual risk. We measured perceived risk by nocturnal rodents using a giving-up density foraging experiment with paired shrub (safe) and open (risky) foraging trays in cheatgrass and native habitats. We also evaluated microhabitat selection across a cheatgrass gradient as an additional assay of perceived risk and behavioral responses for deer mice (Peromyscus maniculatus) at two spatial scales of habitat availability. Finally, we used mark-recapture analysis to quantify deer mouse apparent survival across a cheatgrass gradient while accounting for detection probability and other habitat features. In the foraging experiment, shrubs were more important as protective cover in cheatgrass-dominated habitats, suggesting that cheatgrass increased perceived predation risk. Additionally, deer mice avoided cheatgrass and selected shrubs, and marginally avoided native grass, at two spatial scales. Deer mouse apparent survival varied with a cheatgrass–shrub interaction, corresponding with our foraging experiment results, and providing a rare example of a native plant mediating the effects of an invasive plant on wildlife. By synthesizing the results of three individual lines of evidence (foraging behavior, habitat selection, and apparent survival), we provide a rare example of linkage between behavioral responses of animals indicative of perceived predation risk and actual fitness outcomes. Moreover, our results

  8. Risk Prediction of One-Year Mortality in Patients with Cardiac Arrhythmias Using Random Survival Forest

    Directory of Open Access Journals (Sweden)

    Fen Miao

    2015-01-01

    Full Text Available Existing models for predicting mortality based on traditional Cox proportional hazard approach (CPH often have low prediction accuracy. This paper aims to develop a clinical risk model with good accuracy for predicting 1-year mortality in cardiac arrhythmias patients using random survival forest (RSF, a robust approach for survival analysis. 10,488 cardiac arrhythmias patients available in the public MIMIC II clinical database were investigated, with 3,452 deaths occurring within 1-year followups. Forty risk factors including demographics and clinical and laboratory information and antiarrhythmic agents were analyzed as potential predictors of all-cause mortality. RSF was adopted to build a comprehensive survival model and a simplified risk model composed of 14 top risk factors. The built comprehensive model achieved a prediction accuracy of 0.81 measured by c-statistic with 10-fold cross validation. The simplified risk model also achieved a good accuracy of 0.799. Both results outperformed traditional CPH (which achieved a c-statistic of 0.733 for the comprehensive model and 0.718 for the simplified model. Moreover, various factors are observed to have nonlinear impact on cardiac arrhythmias prognosis. As a result, RSF based model which took nonlinearity into account significantly outperformed traditional Cox proportional hazard model and has great potential to be a more effective approach for survival analysis.

  9. Biochemical Control With Radiotherapy Improves Overall Survival in Intermediate and High-Risk Prostate Cancer Patients Who Have an Estimated 10-Year Overall Survival of >90%

    International Nuclear Information System (INIS)

    Herbert, Christopher; Liu, Mitchell; Tyldesley, Scott; Morris, W. James; Joffres, Michel; Khaira, Mandip; Kwan, Winkle; Moiseenko, Vitali; Pickles, Thomas

    2012-01-01

    Purpose: To identify subgroups of patients with carcinoma of the prostate treated with radical radiotherapy that have improved overall survival when disease is biochemically controlled. Methods and Materials: A cohort of 1,060 prostate cancer patients treated with radical radiotherapy was divided into nine subgroups based on National Comprehensive Cancer Network risk category and estimated 10-year overall survival (eOS 10y) derived from the age adjusted Charlson Comorbidity Index. Patients with and without biochemical control were compared with respect to overall survival. Actuarial estimates of overall survival were calculated using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards models were used for analysis of overall survival. Results: Median follow-up was 125 months (range, 51–176 months). Only the subgroups with high or intermediate risk disease and an eOS 10y of >90% had a statistically significantly improved overall survival when prostate cancer was biochemically controlled. In all other groups, biochemical control made no significant difference to overall survival. In the subgroup with high-risk disease and eOS 10y >90%, actuarial overall survival was 86.3% (95% confidence interval [CI] 78.5%–94.1%) and 62.1% (95% CI 52.9%–71.3%) for patients with biochemical control and biochemical relapse respectively (p = 0.002). In the intermediate risk group with eOS >90%, actuarial overall survival was 95.3% (95% CI 89.0%–100%) and 79.8% (95% CI 68.0%–91.6%) for biochemically controlled and biochemically relapsed patients (p = 0.033). On multivariate analysis, National Comprehensive Cancer Network risk group (p = 0.005), biochemical control (p = 0.033) and eOS 10y (p 90%.

  10. Restoration Survival: Revisiting Patients' Risk Factors Through a Systematic Literature Review.

    Science.gov (United States)

    van de Sande, F H; Collares, K; Correa, M B; Cenci, M S; Demarco, F F; Opdam, Njm

    2016-09-01

    A literature review was conducted to investigate the influence of patient-related factors on restoration survival in posterior permanent teeth as well as to report the methods used to collect these factors. The selection of articles on longitudinal clinical studies investigating the survival of posterior restorations (except full crowns and temporary fillings) and including patient-related factors was performed by applying predefined criteria. The review was organized into two parts, the first describing how patient factors were assessed in the studies (n=45) and the second presenting the statistical significance (n=27) and size of the effect (n=11) of these factors on restoration survival. Patient-related factors mentioned in the studies included age; gender; caries risk; caries activity/severity; decayed, missing, filled teeth; number of restorations; oral hygiene; and bruxism, among others. Sixteen studies included the patient age or age range in the analysis, which was found to be significant in 47% of the studies. Regarding gender, four of 17 reports found a significant effect on survival, showing more failures for men in three studies. The caries risk profile or related variables were included in the analysis of 15 studies, and a significant effect on survival was reported for high-caries-risk individuals (or related variables) in 67% of these studies. Bruxism was also found to influence restoration survival in three of six studies where this variable was investigated. Some issues were found regarding the reporting of methods used to classify patients according to risk and were thoroughly discussed. In view of the information gathered in this review, the assessment of patient factors along with other variables should become part of clinical studies investigating restoration survival, since several of these factors were shown to influence the failure of restorations, regardless of the material type.

  11. Observations on risk analysis

    International Nuclear Information System (INIS)

    Thompson, W.A. Jr.

    1979-11-01

    This paper briefly describes WASH 1400 and the Lewis report. It attempts to define basic concepts such as risk and risk analysis, common mode failure, and rare event. Several probabilistic models which go beyond the WASH 1400 methodology are introduced; the common characteristic of these models is that they recognize explicitly that risk analysis is time dependent whereas WASH 1400 takes a per demand failure rate approach which obscures the important fact that accidents are time related. Further, the presentation of a realistic risk analysis should recognize that there are various risks which compete with one another for the lives of the individuals at risk. A way of doing this is suggested

  12. Incidence and survival of stomach cancer in a high-risk population of Chile

    Science.gov (United States)

    Heise, Katy; Bertran, Enriqueta; Andia, Marcelo E; Ferreccio, Catterina

    2009-01-01

    AIM: To study the incidence and survival rate of stomach cancer (SC) and its associated factors in a high risk population in Chile. METHODS: The population-based cancer registry of Valdivia, included in the International Agency for Research on Cancer system, covers 356 396 residents of Valdivia Province, Southern Chile. We studied all SC cases entered in this Registry during 1998-2002 (529 cases). Population data came from the Chilean census (2002). Standardized incidence rates per 100 000 inhabitants (SIR) using the world population, cumulative risk of developing cancer before age 75, and rate ratios by sex, age, ethnicity and social factors were estimated. Relative survival (Ederer II method) and age-standardized estimates (Brenner method) were calculated. Specific survival rates (Kaplan-Meier) were measured at 3 and 5 years and survival curves were analyzed with the Logrank and Breslow tests. Survival was studied in relation to demographics, clinical presentation, laboratory results and medical management of the cases. Those variables significantly associated with survival were later included in a Cox multivariate model. RESULTS: Between 1998 and 2002, 529 primary gastric cancers occurred in Valdivia (crude incidence rate 29.2 per 100 000 inhabitants). Most cases were male (69.0%), residents of urban areas (57.5%) and Hispanic (83.2%), with a low education level (84.5% Mapuche ethnicity only significant for women (RR 2.2, 95% CI: 1.2-3.7). Of all cases, 76.4% were histologically confirmed, 11.5% had a death certificate only (DCO), 56.1% were TNM stage IV; 445 cases (84.1%) were eligible for survival analysis, all completed five years follow-up; 42 remained alive, 392 died of SC and 11 died from other causes. Specific 5-year survival, excluding cases with DCO, was 10.6% (95% CI: 7.7-13.5); 5-year relative survival rate was 12.3% (95% CI: 9.1-16.1), men 10.9% (95% CI: 7.4-15.2) and women 16.1% (95% CI: 9.5-24.5). Five-year specific survival was higher for patients

  13. Mathematical Methods in Survival Analysis, Reliability and Quality of Life

    CERN Document Server

    Huber, Catherine; Mesbah, Mounir

    2008-01-01

    Reliability and survival analysis are important applications of stochastic mathematics (probability, statistics and stochastic processes) that are usually covered separately in spite of the similarity of the involved mathematical theory. This title aims to redress this situation: it includes 21 chapters divided into four parts: Survival analysis, Reliability, Quality of life, and Related topics. Many of these chapters were presented at the European Seminar on Mathematical Methods for Survival Analysis, Reliability and Quality of Life in 2006.

  14. Survival analysis of heart failure patients: A case study.

    Directory of Open Access Journals (Sweden)

    Tanvir Ahmad

    Full Text Available This study was focused on survival analysis of heart failure patients who were admitted to Institute of Cardiology and Allied hospital Faisalabad-Pakistan during April-December (2015. All the patients were aged 40 years or above, having left ventricular systolic dysfunction, belonging to NYHA class III and IV. Cox regression was used to model mortality considering age, ejection fraction, serum creatinine, serum sodium, anemia, platelets, creatinine phosphokinase, blood pressure, gender, diabetes and smoking status as potentially contributing for mortality. Kaplan Meier plot was used to study the general pattern of survival which showed high intensity of mortality in the initial days and then a gradual increase up to the end of study. Martingale residuals were used to assess functional form of variables. Results were validated computing calibration slope and discrimination ability of model via bootstrapping. For graphical prediction of survival probability, a nomogram was constructed. Age, renal dysfunction, blood pressure, ejection fraction and anemia were found as significant risk factors for mortality among heart failure patients.

  15. Survival analysis of heart failure patients: A case study.

    Science.gov (United States)

    Ahmad, Tanvir; Munir, Assia; Bhatti, Sajjad Haider; Aftab, Muhammad; Raza, Muhammad Ali

    2017-01-01

    This study was focused on survival analysis of heart failure patients who were admitted to Institute of Cardiology and Allied hospital Faisalabad-Pakistan during April-December (2015). All the patients were aged 40 years or above, having left ventricular systolic dysfunction, belonging to NYHA class III and IV. Cox regression was used to model mortality considering age, ejection fraction, serum creatinine, serum sodium, anemia, platelets, creatinine phosphokinase, blood pressure, gender, diabetes and smoking status as potentially contributing for mortality. Kaplan Meier plot was used to study the general pattern of survival which showed high intensity of mortality in the initial days and then a gradual increase up to the end of study. Martingale residuals were used to assess functional form of variables. Results were validated computing calibration slope and discrimination ability of model via bootstrapping. For graphical prediction of survival probability, a nomogram was constructed. Age, renal dysfunction, blood pressure, ejection fraction and anemia were found as significant risk factors for mortality among heart failure patients.

  16. Quantifying discrimination of Framingham risk functions with different survival C statistics.

    Science.gov (United States)

    Pencina, Michael J; D'Agostino, Ralph B; Song, Linye

    2012-07-10

    Cardiovascular risk prediction functions offer an important diagnostic tool for clinicians and patients themselves. They are usually constructed with the use of parametric or semi-parametric survival regression models. It is essential to be able to evaluate the performance of these models, preferably with summaries that offer natural and intuitive interpretations. The concept of discrimination, popular in the logistic regression context, has been extended to survival analysis. However, the extension is not unique. In this paper, we define discrimination in survival analysis as the model's ability to separate those with longer event-free survival from those with shorter event-free survival within some time horizon of interest. This definition remains consistent with that used in logistic regression, in the sense that it assesses how well the model-based predictions match the observed data. Practical and conceptual examples and numerical simulations are employed to examine four C statistics proposed in the literature to evaluate the performance of survival models. We observe that they differ in the numerical values and aspects of discrimination that they capture. We conclude that the index proposed by Harrell is the most appropriate to capture discrimination described by the above definition. We suggest researchers report which C statistic they are using, provide a rationale for their selection, and be aware that comparing different indices across studies may not be meaningful. Copyright © 2012 John Wiley & Sons, Ltd.

  17. Proteomic Analysis Reveals Autophagy as Pro-Survival Pathway Elicited by Long-Term Exposure with 5-Azacitidine in High-Risk Myelodysplasia.

    Science.gov (United States)

    Romano, Alessandra; Giallongo, Cesarina; La Cava, Piera; Parrinello, Nunziatina L; Chiechi, Antonella; Vetro, Calogero; Tibullo, Daniele; Di Raimondo, Francesco; Liotta, Lance A; Espina, Virginia; Palumbo, Giuseppe A

    2017-01-01

    Azacytidine (5-AZA) is the standard first-choice treatment for high-risk myelodysplasia (MDS) patients. However, the clinical outcome for those patients who interrupt treatment or whose disease failed to respond is very poor. In order to identify the cellular pathways that are modified by long-term exposure to 5-AZA, we evaluated key proteins associated with the autophagy pathway by reverse-phase microarray (RPPA). Comparing bone marrow mononucleated cells (BMMCs) obtained from 20 newly-diagnosed patients and after four 5-AZA cycles we found an increased autophagy signaling. We then evaluated ex-vivo the effect of the combination of 5-AZA with autophagy inhibitors chloroquine (CQ) and leupeptin. Since 5-AZA and CQ showed synergism due to an increase of basal autophagy after 5-AZA exposure, we adopted a sequential treatment treating BMMCs with 5 μM 5-AZA for 72 h followed by 10 μM CQ for 24 h and found increased apoptosis, associated to a reduction of G2M phase and increase in G0-G1 phase. Long-term exposure to 5-AZA induced the reduction of the autophagic marker SQSTM1/p62, reversible by CQ or leupeptin exposure. In conclusion, we identified autophagy as a compensatory pathway occurring in MDS-BM after long-term exposure to 5-AZA and we provided evidences that a sequential treatment of 5-AZA followed by CQ could improve 5-AZA efficacy, providing novel insight for tailored therapy in MDS patients progressing after 5-AZA therapy.

  18. Proteomic Analysis Reveals Autophagy as Pro-Survival Pathway Elicited by Long-Term Exposure with 5-Azacitidine in High-Risk Myelodysplasia

    Directory of Open Access Journals (Sweden)

    Alessandra Romano

    2017-04-01

    Full Text Available Azacytidine (5-AZA is the standard first-choice treatment for high-risk myelodysplasia (MDS patients. However, the clinical outcome for those patients who interrupt treatment or whose disease failed to respond is very poor. In order to identify the cellular pathways that are modified by long-term exposure to 5-AZA, we evaluated key proteins associated with the autophagy pathway by reverse-phase microarray (RPPA. Comparing bone marrow mononucleated cells (BMMCs obtained from 20 newly-diagnosed patients and after four 5-AZA cycles we found an increased autophagy signaling. We then evaluated ex-vivo the effect of the combination of 5-AZA with autophagy inhibitors chloroquine (CQ and leupeptin. Since 5-AZA and CQ showed synergism due to an increase of basal autophagy after 5-AZA exposure, we adopted a sequential treatment treating BMMCs with 5 μM 5-AZA for 72 h followed by 10 μM CQ for 24 h and found increased apoptosis, associated to a reduction of G2M phase and increase in G0-G1 phase. Long-term exposure to 5-AZA induced the reduction of the autophagic marker SQSTM1/p62, reversible by CQ or leupeptin exposure. In conclusion, we identified autophagy as a compensatory pathway occurring in MDS-BM after long-term exposure to 5-AZA and we provided evidences that a sequential treatment of 5-AZA followed by CQ could improve 5-AZA efficacy, providing novel insight for tailored therapy in MDS patients progressing after 5-AZA therapy.

  19. Survival analysis approach to account for non-exponential decay rate effects in lifetime experiments

    Energy Technology Data Exchange (ETDEWEB)

    Coakley, K.J., E-mail: kevincoakley@nist.gov [National Institute of Standards and Technology, 325 Broadway, Boulder, CO 80305 (United States); Dewey, M.S.; Huber, M.G. [National Institute of Standards and Technology, 100 Bureau Drive, Stop 8461, Gaithersburg, MD 20899 (United States); Huffer, C.R.; Huffman, P.R. [North Carolina State University, 2401 Stinson Drive, Box 8202, Raleigh, NC 27695 (United States); Triangle Universities Nuclear Laboratory, 116 Science Drive, Box 90308, Durham, NC 27708 (United States); Marley, D.E. [National Institute of Standards and Technology, 100 Bureau Drive, Stop 8461, Gaithersburg, MD 20899 (United States); North Carolina State University, 2401 Stinson Drive, Box 8202, Raleigh, NC 27695 (United States); Mumm, H.P. [National Institute of Standards and Technology, 100 Bureau Drive, Stop 8461, Gaithersburg, MD 20899 (United States); O' Shaughnessy, C.M. [University of North Carolina at Chapel Hill, 120 E. Cameron Ave., CB #3255, Chapel Hill, NC 27599 (United States); Triangle Universities Nuclear Laboratory, 116 Science Drive, Box 90308, Durham, NC 27708 (United States); Schelhammer, K.W. [North Carolina State University, 2401 Stinson Drive, Box 8202, Raleigh, NC 27695 (United States); Triangle Universities Nuclear Laboratory, 116 Science Drive, Box 90308, Durham, NC 27708 (United States); Thompson, A.K.; Yue, A.T. [National Institute of Standards and Technology, 100 Bureau Drive, Stop 8461, Gaithersburg, MD 20899 (United States)

    2016-03-21

    In experiments that measure the lifetime of trapped particles, in addition to loss mechanisms with exponential survival probability functions, particles can be lost by mechanisms with non-exponential survival probability functions. Failure to account for such loss mechanisms produces systematic measurement error and associated systematic uncertainties in these measurements. In this work, we develop a general competing risks survival analysis method to account for the joint effect of loss mechanisms with either exponential or non-exponential survival probability functions, and a method to quantify the size of systematic effects and associated uncertainties for lifetime estimates. As a case study, we apply our survival analysis formalism and method to the Ultra Cold Neutron lifetime experiment at NIST. In this experiment, neutrons can escape a magnetic trap before they decay due to a wall loss mechanism with an associated non-exponential survival probability function.

  20. Survival analysis approach to account for non-exponential decay rate effects in lifetime experiments

    International Nuclear Information System (INIS)

    Coakley, K.J.; Dewey, M.S.; Huber, M.G.; Huffer, C.R.; Huffman, P.R.; Marley, D.E.; Mumm, H.P.; O'Shaughnessy, C.M.; Schelhammer, K.W.; Thompson, A.K.; Yue, A.T.

    2016-01-01

    In experiments that measure the lifetime of trapped particles, in addition to loss mechanisms with exponential survival probability functions, particles can be lost by mechanisms with non-exponential survival probability functions. Failure to account for such loss mechanisms produces systematic measurement error and associated systematic uncertainties in these measurements. In this work, we develop a general competing risks survival analysis method to account for the joint effect of loss mechanisms with either exponential or non-exponential survival probability functions, and a method to quantify the size of systematic effects and associated uncertainties for lifetime estimates. As a case study, we apply our survival analysis formalism and method to the Ultra Cold Neutron lifetime experiment at NIST. In this experiment, neutrons can escape a magnetic trap before they decay due to a wall loss mechanism with an associated non-exponential survival probability function.

  1. Is risk analysis scientific?

    Science.gov (United States)

    Hansson, Sven Ove; Aven, Terje

    2014-07-01

    This article discusses to what extent risk analysis is scientific in view of a set of commonly used definitions and criteria. We consider scientific knowledge to be characterized by its subject matter, its success in developing the best available knowledge in its fields of study, and the epistemic norms and values that guide scientific investigations. We proceed to assess the field of risk analysis according to these criteria. For this purpose, we use a model for risk analysis in which science is used as a base for decision making on risks, which covers the five elements evidence, knowledge base, broad risk evaluation, managerial review and judgment, and the decision; and that relates these elements to the domains experts and decisionmakers, and to the domains fact-based or value-based. We conclude that risk analysis is a scientific field of study, when understood as consisting primarily of (i) knowledge about risk-related phenomena, processes, events, etc., and (ii) concepts, theories, frameworks, approaches, principles, methods and models to understand, assess, characterize, communicate, and manage risk, in general and for specific applications (the instrumental part). © 2014 Society for Risk Analysis.

  2. Overall survival in lower IPSS risk MDS by receipt of iron chelation therapy, adjusting for patient-related factors and measuring from time of first red blood cell transfusion dependence: an MDS-CAN analysis.

    Science.gov (United States)

    Leitch, Heather A; Parmar, Ambica; Wells, Richard A; Chodirker, Lisa; Zhu, Nancy; Nevill, Thomas J; Yee, Karen W L; Leber, Brian; Keating, Mary-Margaret; Sabloff, Mitchell; St Hilaire, Eve; Kumar, Rajat; Delage, Robert; Geddes, Michelle; Storring, John M; Kew, Andrea; Shamy, April; Elemary, Mohamed; Lenis, Martha; Mamedov, Alexandre; Ivo, Jessica; Francis, Janika; Zhang, Liying; Buckstein, Rena

    2017-10-01

    Analyses suggest iron overload in red blood cell (RBC) transfusion-dependent (TD) patients with myleodysplastic syndrome (MDS) portends inferior overall survival (OS) that is attenuated by iron chelation therapy (ICT) but may be biassed by unbalanced patient-related factors. The Canadian MDS Registry prospectively measures frailty, comorbidity and disability. We analysed OS by receipt of ICT, adjusting for these patient-related factors. TD International Prognostic Scoring System (IPSS) low and intermediate-1 risk MDS, at RBC TD, were included. Predictive factors for OS were determined. A matched pair analysis considering age, revised IPSS, TD severity, time from MDS diagnosis to TD, and receipt of disease-modifying agents was conducted. Of 239 patients, 83 received ICT; frailty, comorbidity and disability did not differ from non-ICT patients. Median OS from TD was superior in ICT patients (5·2 vs. 2·1 years; P MDS, adjusting for age, frailty, comorbidity, disability, revised IPSS, TD severity, time to TD and receiving disease-modifying agents. This provides additional evidence that ICT may confer clinical benefit. © 2017 John Wiley & Sons Ltd.

  3. Comparative risk analysis

    International Nuclear Information System (INIS)

    Niehaus, F.

    1988-01-01

    In this paper, the risks of various energy systems are discussed considering severe accidents analysis, particularly the probabilistic safety analysis, and probabilistic safety criteria, and the applications of these criteria and analysis. The comparative risk analysis has demonstrated that the largest source of risk in every society is from daily small accidents. Nevertheless, we have to be more concerned about severe accidents. The comparative risk analysis of five different energy systems (coal, oil, gas, LWR and STEC (Solar)) for the public has shown that the main sources of risks are coal and oil. The latest comparative risk study of various energy has been conducted in the USA and has revealed that the number of victims from coal is 42 as many than victims from nuclear. A study for severe accidents from hydro-dams in United States has estimated the probability of dam failures at 1 in 10,000 years and the number of victims between 11,000 and 260,000. The average occupational risk from coal is one fatal accident in 1,000 workers/year. The probabilistic safety analysis is a method that can be used to assess nuclear energy risks, and to analyze the severe accidents, and to model all possible accident sequences and consequences. The 'Fault tree' analysis is used to know the probability of failure of the different systems at each point of accident sequences and to calculate the probability of risks. After calculating the probability of failure, the criteria for judging the numerical results have to be developed, that is the quantitative and qualitative goals. To achieve these goals, several systems have been devised by various countries members of AIEA. The probabilistic safety ana-lysis method has been developed by establishing a computer program permit-ting to know different categories of safety related information. 19 tabs. (author)

  4. Carfilzomib significantly improves the progression-free survival of high-risk patients in multiple myeloma.

    Science.gov (United States)

    Avet-Loiseau, Hervé; Fonseca, Rafael; Siegel, David; Dimopoulos, Meletios A; Špička, Ivan; Masszi, Tamás; Hájek, Roman; Rosiñol, Laura; Goranova-Marinova, Vesselina; Mihaylov, Georgi; Maisnar, Vladimír; Mateos, Maria-Victoria; Wang, Michael; Niesvizky, Ruben; Oriol, Albert; Jakubowiak, Andrzej; Minarik, Jiri; Palumbo, Antonio; Bensinger, William; Kukreti, Vishal; Ben-Yehuda, Dina; Stewart, A Keith; Obreja, Mihaela; Moreau, Philippe

    2016-09-01

    The presence of certain high-risk cytogenetic abnormalities, such as translocations (4;14) and (14;16) and deletion (17p), are known to have a negative impact on survival in multiple myeloma (MM). The phase 3 study ASPIRE (N = 792) demonstrated that progression-free survival (PFS) was significantly improved with carfilzomib, lenalidomide, and dexamethasone (KRd), compared with lenalidomide and dexamethasone (Rd) in relapsed MM. This preplanned subgroup analysis of ASPIRE was conducted to evaluate KRd vs Rd by baseline cytogenetics according to fluorescence in situ hybridization. Of 417 patients with known cytogenetic risk status, 100 patients (24%) were categorized with high-risk cytogenetics (KRd, n = 48; Rd, n = 52) and 317 (76%) were categorized with standard-risk cytogenetics (KRd, n = 147; Rd, n = 170). For patients with high-risk cytogenetics, treatment with KRd resulted in a median PFS of 23.1 months, a 9-month improvement relative to treatment with Rd. For patients with standard-risk cytogenetics, treatment with KRd led to a 10-month improvement in median PFS vs Rd. The overall response rates for KRd vs Rd were 79.2% vs 59.6% (high-risk cytogenetics) and 91.2% vs 73.5% (standard-risk cytogenetics); approximately fivefold as many patients with high- or standard-risk cytogenetics achieved a complete response or better with KRd vs Rd (29.2% vs 5.8% and 38.1% vs 6.5%, respectively). KRd improved but did not abrogate the poor prognosis associated with high-risk cytogenetics. This regimen had a favorable benefit-risk profile in patients with relapsed MM, irrespective of cytogenetic risk status, and should be considered a standard of care in these patients. This trial was registered at www.clinicaltrials.gov as #NCT01080391. © 2016 by The American Society of Hematology.

  5. Information Security Risk Analysis

    CERN Document Server

    Peltier, Thomas R

    2010-01-01

    Offers readers with the knowledge and the skill-set needed to achieve a highly effective risk analysis assessment. This title demonstrates how to identify threats and then determine if those threats pose a real risk. It is suitable for industry and academia professionals.

  6. Primary blast survival and injury risk assessment for repeated blast exposures.

    Science.gov (United States)

    Panzer, Matthew B; Bass, Cameron R Dale; Rafaels, Karin A; Shridharani, Jay; Capehart, Bruce P

    2012-02-01

    The widespread use of explosives by modern insurgents and terrorists has increased the potential frequency of blast exposure in soldiers and civilians. This growing threat highlights the importance of understanding and evaluating blast injury risk and the increase of injury risk from exposure to repeated blast effects. Data from more than 3,250 large animal experiments were collected from studies focusing on the effects of blast exposure. The current study uses 2,349 experiments from the data collection for analysis of the primary blast injury and survival risk for both long- and short-duration blasts, including the effects from repeated exposures. A piecewise linear logistic regression was performed on the data to develop survival and injury risk assessment curves. New injury risk assessment curves uniting long- and short-duration blasts were developed for incident and reflected pressure measures and were used to evaluate the risk of injury based on blast over pressure, positive-phase duration, and the number of repeated exposures. The risk assessments were derived for three levels of injury severity: nonauditory, pulmonary, and fatality. The analysis showed a marked initial decrease in injury tolerance with each subsequent blast exposure. This effect decreases with increasing number of blast exposures. The new injury risk functions showed good agreement with the existing experimental data and provided a simplified model for primary blast injury risk. This model can be used to predict blast injury or fatality risk for single exposure and repeated exposure cases and has application in modern combat scenarios or in setting occupational health limits. .Copyright © 2012 by Lippincott Williams & Wilkins

  7. Pseudo-observations in survival analysis

    DEFF Research Database (Denmark)

    Andersen, Per Kragh; Perme, Maja Pohar

    2010-01-01

    -state models, e.g. the competing risks cumulative incidence function. Graphical and numerical methods for assessing goodness-of-fit for hazard regression models and for the Fine-Gray model in competing risks studies based on pseudo-observations are also reviewed. Sensitivity to covariate-dependent censoring...

  8. Covariate analysis of bivariate survival data

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, L.E.

    1992-01-01

    The methods developed are used to analyze the effects of covariates on bivariate survival data when censoring and ties are present. The proposed method provides models for bivariate survival data that include differential covariate effects and censored observations. The proposed models are based on an extension of the univariate Buckley-James estimators which replace censored data points by their expected values, conditional on the censoring time and the covariates. For the bivariate situation, it is necessary to determine the expectation of the failure times for one component conditional on the failure or censoring time of the other component. Two different methods have been developed to estimate these expectations. In the semiparametric approach these expectations are determined from a modification of Burke's estimate of the bivariate empirical survival function. In the parametric approach censored data points are also replaced by their conditional expected values where the expected values are determined from a specified parametric distribution. The model estimation will be based on the revised data set, comprised of uncensored components and expected values for the censored components. The variance-covariance matrix for the estimated covariate parameters has also been derived for both the semiparametric and parametric methods. Data from the Demographic and Health Survey was analyzed by these methods. The two outcome variables are post-partum amenorrhea and breastfeeding; education and parity were used as the covariates. Both the covariate parameter estimates and the variance-covariance estimates for the semiparametric and parametric models will be compared. In addition, a multivariate test statistic was used in the semiparametric model to examine contrasts. The significance of the statistic was determined from a bootstrap distribution of the test statistic.

  9. A survival analysis on critical components of nuclear power plants

    International Nuclear Information System (INIS)

    Durbec, V.; Pitner, P.; Riffard, T.

    1995-06-01

    Some tubes of heat exchangers of nuclear power plants may be affected by Primary Water Stress Corrosion Cracking (PWSCC) in highly stressed areas. These defects can shorten the lifetime of the component and lead to its replacement. In order to reduce the risk of cracking, a preventive remedial operation called shot peening was applied on the French reactors between 1985 and 1988. To assess and investigate the effects of shot peening, a statistical analysis was carried on the tube degradation results obtained from in service inspection that are regularly conducted using non destructive tests. The statistical method used is based on the Cox proportional hazards model, a powerful tool in the analysis of survival data, implemented in PROC PHRED recently available in SAS/STAT. This technique has a number of major advantages including the ability to deal with censored failure times data and with the complication of time-dependant co-variables. The paper focus on the modelling and a presentation of the results given by SAS. They provide estimate of how the relative risk of degradation changes after peening and indicate for which values of the prognostic factors analyzed the treatment is likely to be most beneficial. (authors). 2 refs., 3 figs., 6 tabs

  10. Volumetric and MGMT parameters in glioblastoma patients: Survival analysis

    International Nuclear Information System (INIS)

    Iliadis, Georgios; Kotoula, Vassiliki; Chatzisotiriou, Athanasios; Televantou, Despina; Eleftheraki, Anastasia G; Lambaki, Sofia; Misailidou, Despina; Selviaridis, Panagiotis; Fountzilas, George

    2012-01-01

    In this study several tumor-related volumes were assessed by means of a computer-based application and a survival analysis was conducted to evaluate the prognostic significance of pre- and postoperative volumetric data in patients harboring glioblastomas. In addition, MGMT (O 6 -methylguanine methyltransferase) related parameters were compared with those of volumetry in order to observe possible relevance of this molecule in tumor development. We prospectively analyzed 65 patients suffering from glioblastoma (GBM) who underwent radiotherapy with concomitant adjuvant temozolomide. For the purpose of volumetry T1 and T2-weighted magnetic resonance (MR) sequences were used, acquired both pre- and postoperatively (pre-radiochemotherapy). The volumes measured on preoperative MR images were necrosis, enhancing tumor and edema (including the tumor) and on postoperative ones, net-enhancing tumor. Age, sex, performance status (PS) and type of operation were also included in the multivariate analysis. MGMT was assessed for promoter methylation with Multiplex Ligation-dependent Probe Amplification (MLPA), for RNA expression with real time PCR, and for protein expression with immunohistochemistry in a total of 44 cases with available histologic material. In the multivariate analysis a negative impact was shown for pre-radiochemotherapy net-enhancing tumor on the overall survival (OS) (p = 0.023) and for preoperative necrosis on progression-free survival (PFS) (p = 0.030). Furthermore, the multivariate analysis confirmed the importance of PS in PFS and OS of patients. MGMT promoter methylation was observed in 13/23 (43.5%) evaluable tumors; complete methylation was observed in 3/13 methylated tumors only. High rate of MGMT protein positivity (> 20% positive neoplastic nuclei) was inversely associated with pre-operative tumor necrosis (p = 0.021). Our findings implicate that volumetric parameters may have a significant role in the prognosis of GBM patients. Furthermore

  11. Component of the risk analysis

    International Nuclear Information System (INIS)

    Martinez, I.; Campon, G.

    2013-01-01

    The power point presentation reviews issues like analysis of risk (Codex), management risk, preliminary activities manager, relationship between government and industries, microbiological danger and communication of risk

  12. Unsharpness-risk analysis

    International Nuclear Information System (INIS)

    Preyssl, C.

    1986-01-01

    Safety analysis provides the only tool for evaluation and quantification of rare or hypothetical events leading to system failure. So far probability theory has been used for the fault- and event-tree methodology. The phenomenon of uncertainties constitutes an important aspect in risk analysis. Uncertainties can be classified as originating from 'randomness' or 'fuzziness'. Probability theory addresses randomness only. The use of 'fuzzy set theory' makes it possible to include both types of uncertainty in the mathematical model of risk analysis. Thus the 'fuzzy fault tree' is expressed in 'possibilistic' terms implying a range of simplifications and improvements. 'Human failure' and 'conditionality' can be treated correctly. Only minimum-maximum relations are used to combine the possibility distributions of events. Various event-classifications facilitate the interpretation of the results. The method is demonstrated by application to a TRIGA-research reactor. Uncertainty as an implicit part of 'fuzzy risk' can be quantified explicitly using an 'uncertainty measure'. Based on this the 'degree of relative compliance' with a quantizative safety goal can be defined for a particular risk. The introduction of 'weighting functionals' guarantees the consideration of the importances attached to different parts of the risk exceeding or complying with the standard. The comparison of two reference systems is demonstrated in a case study. It is concluded that any application of the 'fuzzy risk analysis' has to be free of any hypostatization when reducing subjective to objective information. (Author)

  13. A Framework for RFID Survivability Requirement Analysis and Specification

    Science.gov (United States)

    Zuo, Yanjun; Pimple, Malvika; Lande, Suhas

    Many industries are becoming dependent on Radio Frequency Identification (RFID) technology for inventory management and asset tracking. The data collected about tagged objects though RFID is used in various high level business operations. The RFID system should hence be highly available, reliable, and dependable and secure. In addition, this system should be able to resist attacks and perform recovery in case of security incidents. Together these requirements give rise to the notion of a survivable RFID system. The main goal of this paper is to analyze and specify the requirements for an RFID system to become survivable. These requirements, if utilized, can assist the system in resisting against devastating attacks and recovering quickly from damages. This paper proposes the techniques and approaches for RFID survivability requirements analysis and specification. From the perspective of system acquisition and engineering, survivability requirement is the important first step in survivability specification, compliance formulation, and proof verification.

  14. Adversarial risk analysis

    CERN Document Server

    Banks, David L; Rios Insua, David

    2015-01-01

    Flexible Models to Analyze Opponent Behavior A relatively new area of research, adversarial risk analysis (ARA) informs decision making when there are intelligent opponents and uncertain outcomes. Adversarial Risk Analysis develops methods for allocating defensive or offensive resources against intelligent adversaries. Many examples throughout illustrate the application of the ARA approach to a variety of games and strategic situations. The book shows decision makers how to build Bayesian models for the strategic calculation of their opponents, enabling decision makers to maximize their expected utility or minimize their expected loss. This new approach to risk analysis asserts that analysts should use Bayesian thinking to describe their beliefs about an opponent's goals, resources, optimism, and type of strategic calculation, such as minimax and level-k thinking. Within that framework, analysts then solve the problem from the perspective of the opponent while placing subjective probability distributions on a...

  15. Polymorphisms in chemokine and receptor genes and gastric cancer risk and survival in a high risk Polish population.

    Science.gov (United States)

    Gawron, Andrew J; Fought, Angela J; Lissowska, Jolanta; Ye, Weimin; Zhang, Xiao; Chow, Wong-Ho; Beane Freeman, Laura E; Hou, Lifang

    2011-03-01

    To examine if genetic variations in chemokine receptor and ligand genes are associated with gastric cancer risk and survival. The study included 298 cases and 417 controls from a population-based study of gastric cancer conducted in Warsaw, Poland in 1994-1996. We investigated seven single nucleotide polymorphisms in a chemokine ligand (CXCL12) and chemokine receptor (CCR2, CCR5, CX3CR1) genes and one frameshift deletion (CCR5) in blood leukocyte DNA in relation to gastric cancer risk and survival. Genotyping was conducted at the NCI Core Genotyping Facility. Odds ratios and 95% confidence intervals were computed using univariate and multivariate logistic regression models. Survival analysis was performed using Cox proportional hazards models. Gastric cancer risk was not associated with single chemokine polymorphisms. A CCR5 haplotype that contained the common alleles of IVS1+151 G>T (rs2734648), IVS2+80 C>T (rs1800024) and minor allele of IVS1+246 A>G (rs1799987) was associated with a borderline significantly increased risk (OR = 1.5, 95% CI: 1.0?2.2). For gastric cancer cases, there was a greater risk of death for carriers of the minor alleles of CCR2 Ex2+241 G>A (rs1799864) (HR = 1.5, 95% CI: 1.1-2.1) and CCR5 IVS2+80 C>T (rs1800024) (HR = 1.5, 95% CI: 1.1-2.1). Carriers of the CCR5 minor allele of IVS1+151 G>T (rs2734648) had a decreased risk of death compared to homozygote carriers of the common allele (HR = 0.8, 95% CI: 0.6-1.0). Our findings do not support an association between gastric cancer risk and single chemokine genetic variation. The observed associations between cancer risk and a CCR5 haplotype and between survival and polymorphisms in CCR2 and CCR5 need replication in future studies.

  16. Qualitative analysis of Adenomatous Polyposis Coli promoter: Hypermethylation, engagement and effects on survival of patients with esophageal cancer in a high risk region of the world, a potential molecular marker

    International Nuclear Information System (INIS)

    Zare, Maryam; Jazii, Ferdous Rastgar; Alivand, Mohammad Reza; Nasseri, Negin Karimi; Malekzadeh, Reza; Yazdanbod, Mansour

    2009-01-01

    survival for patients with methylated APC promoter following their treatment. Further investigation into the association between promoter hypermethylation and tumor differentiation status indicated that patients with well differentiated tumors were more likely to develop promoter hypermethylation. Observing similar level of APC promoter hypermethylation in patients with SCCE in this high risk region and comparing it with other parts of the world could support the hypothesis that a common molecular mechanism might be involved in tumorigenesis of SCCE. In addition, the higher rate of two-year survival for patients with unmethylated APC promoter as well as its relationship with tumor differentiation would suggest that this tumor suppressor could be an appropriate candidate molecular marker for evaluating tumor malignancy and predicting survival of patients subsequent to treatment

  17. Qualitative analysis of Adenomatous Polyposis Coli promoter: Hypermethylation, engagement and effects on survival of patients with esophageal cancer in a high risk region of the world, a potential molecular marker

    Directory of Open Access Journals (Sweden)

    Nasseri Negin

    2009-01-01

    to promoter hypermethylation showed a lower rate of survival for patients with methylated APC promoter following their treatment. Further investigation into the association between promoter hypermethylation and tumor differentiation status indicated that patients with well differentiated tumors were more likely to develop promoter hypermethylation. Conclusion Observing similar level of APC promoter hypermethylation in patients with SCCE in this high risk region and comparing it with other parts of the world could support the hypothesis that a common molecular mechanism might be involved in tumorigenesis of SCCE. In addition, the higher rate of two-year survival for patients with unmethylated APC promoter as well as its relationship with tumor differentiation would suggest that this tumor suppressor could be an appropriate candidate molecular marker for evaluating tumor malignancy and predicting survival of patients subsequent to treatment.

  18. Prognostic and survival analysis of 837 Chinese colorectal cancer patients.

    Science.gov (United States)

    Yuan, Ying; Li, Mo-Dan; Hu, Han-Guang; Dong, Cai-Xia; Chen, Jia-Qi; Li, Xiao-Fen; Li, Jing-Jing; Shen, Hong

    2013-05-07

    To develop a prognostic model to predict survival of patients with colorectal cancer (CRC). Survival data of 837 CRC patients undergoing surgery between 1996 and 2006 were collected and analyzed by univariate analysis and Cox proportional hazard regression model to reveal the prognostic factors for CRC. All data were recorded using a standard data form and analyzed using SPSS version 18.0 (SPSS, Chicago, IL, United States). Survival curves were calculated by the Kaplan-Meier method. The log rank test was used to assess differences in survival. Univariate hazard ratios and significant and independent predictors of disease-specific survival and were identified by Cox proportional hazard analysis. The stepwise procedure was set to a threshold of 0.05. Statistical significance was defined as P analysis suggested age, preoperative obstruction, serum carcinoembryonic antigen level at diagnosis, status of resection, tumor size, histological grade, pathological type, lymphovascular invasion, invasion of adjacent organs, and tumor node metastasis (TNM) staging were positive prognostic factors (P analysis showed a significant statistical difference in 3-year survival among these groups: LNR1, 73%; LNR2, 55%; and LNR3, 42% (P analysis results showed that histological grade, depth of bowel wall invasion, and number of metastatic lymph nodes were the most important prognostic factors for CRC if we did not consider the interaction of the TNM staging system (P < 0.05). When the TNM staging was taken into account, histological grade lost its statistical significance, while the specific TNM staging system showed a statistically significant difference (P < 0.0001). The overall survival of CRC patients has improved between 1996 and 2006. LNR is a powerful factor for estimating the survival of stage III CRC patients.

  19. Modelling the joint distribution of competing risks survival times using copula functions

    OpenAIRE

    Kaishev, V. K.; Haberman, S.; Dimitrova, D. S.

    2005-01-01

    The problem of modelling the joint distribution of survival times in a competing risks model, using copula functions is considered. In order to evaluate this joint distribution and the related overall survival function, a system of non-linear differential equations is solved, which relates the crude and net survival functions of the modelled competing risks, through the copula. A similar approach to modelling dependent multiple decrements was applied by Carriere (1994) who used a Gaussian cop...

  20. A balanced hazard ratio for risk group evaluation from survival data.

    Science.gov (United States)

    Branders, Samuel; Dupont, Pierre

    2015-07-30

    Common clinical studies assess the quality of prognostic factors, such as gene expression signatures, clinical variables or environmental factors, and cluster patients into various risk groups. Typical examples include cancer clinical trials where patients are clustered into high or low risk groups. Whenever applied to survival data analysis, such groups are intended to represent patients with similar survival odds and to select the most appropriate therapy accordingly. The relevance of such risk groups, and of the related prognostic factors, is typically assessed through the computation of a hazard ratio. We first stress three limitations of assessing risk groups through the hazard ratio: (1) it may promote the definition of arbitrarily unbalanced risk groups; (2) an apparently optimal group hazard ratio can be largely inconsistent with the p-value commonly associated to it; and (3) some marginal changes between risk group proportions may lead to highly different hazard ratio values. Those issues could lead to inappropriate comparisons between various prognostic factors. Next, we propose the balanced hazard ratio to solve those issues. This new performance metric keeps an intuitive interpretation and is as simple to compute. We also show how the balanced hazard ratio leads to a natural cut-off choice to define risk groups from continuous risk scores. The proposed methodology is validated through controlled experiments for which a prescribed cut-off value is defined by design. Further results are also reported on several cancer prognosis studies, and the proposed methodology could be applied more generally to assess the quality of any prognostic markers. Copyright © 2015 John Wiley & Sons, Ltd.

  1. Prognostic classification index in Iranian colorectal cancer patients: Survival tree analysis

    Directory of Open Access Journals (Sweden)

    Amal Saki Malehi

    2016-01-01

    Full Text Available Aims: The aim of this study was to determine the prognostic index for separating homogenous subgroups in colorectal cancer (CRC patients based on clinicopathological characteristics using survival tree analysis. Methods: The current study was conducted at the Research Center of Gastroenterology and Liver Disease, Shahid Beheshti Medical University in Tehran, between January 2004 and January 2009. A total of 739 patients who already have been diagnosed with CRC based on pathologic report were enrolled. The data included demographic and clinical-pathological characteristic of patients. Tree-structured survival analysis based on a recursive partitioning algorithm was implemented to evaluate prognostic factors. The probability curves were calculated according to the Kaplan-Meier method, and the hazard ratio was estimated as an interest effect size. Result: There were 526 males (71.2% of these patients. The mean survival time (from diagnosis time was 42.46± (3.4. Survival tree identified three variables as main prognostic factors and based on their four prognostic subgroups was constructed. The log-rank test showed good separation of survival curves. Patients with Stage I-IIIA and treated with surgery as the first treatment showed low risk (median = 34 months whereas patients with stage IIIB, IV, and more than 68 years have the worse survival outcome (median = 9.5 months. Conclusion: Constructing the prognostic classification index via survival tree can aid the researchers to assess interaction between clinical variables and determining the cumulative effect of these variables on survival outcome.

  2. Breast cancer data analysis for survivability studies and prediction.

    Science.gov (United States)

    Shukla, Nagesh; Hagenbuchner, Markus; Win, Khin Than; Yang, Jack

    2018-03-01

    Breast cancer is the most common cancer affecting females worldwide. Breast cancer survivability prediction is challenging and a complex research task. Existing approaches engage statistical methods or supervised machine learning to assess/predict the survival prospects of patients. The main objectives of this paper is to develop a robust data analytical model which can assist in (i) a better understanding of breast cancer survivability in presence of missing data, (ii) providing better insights into factors associated with patient survivability, and (iii) establishing cohorts of patients that share similar properties. Unsupervised data mining methods viz. the self-organising map (SOM) and density-based spatial clustering of applications with noise (DBSCAN) is used to create patient cohort clusters. These clusters, with associated patterns, were used to train multilayer perceptron (MLP) model for improved patient survivability analysis. A large dataset available from SEER program is used in this study to identify patterns associated with the survivability of breast cancer patients. Information gain was computed for the purpose of variable selection. All of these methods are data-driven and require little (if any) input from users or experts. SOM consolidated patients into cohorts of patients with similar properties. From this, DBSCAN identified and extracted nine cohorts (clusters). It is found that patients in each of the nine clusters have different survivability time. The separation of patients into clusters improved the overall survival prediction accuracy based on MLP and revealed intricate conditions that affect the accuracy of a prediction. A new, entirely data driven approach based on unsupervised learning methods improves understanding and helps identify patterns associated with the survivability of patient. The results of the analysis can be used to segment the historical patient data into clusters or subsets, which share common variable values and

  3. [Essential thrombocythemia: baseline characteristics and risk factors for survival and thrombosis in a series of 214 patients].

    Science.gov (United States)

    Angona, Anna; Alvarez-Larrán, Alberto; Bellosillo, Beatriz; Martínez-Avilés, Luz; Garcia-Pallarols, Francesc; Longarón, Raquel; Ancochea, Àgueda; Besses, Carles

    2015-03-15

    Two prognostic models to predict overall survival and thrombosis-free survival have been proposed: International Prognostic Score for Essential Thrombocythemia (IPSET) and IPSET-Thrombosis, respectively, based on age, leukocytes count, history of previous thrombosis, the presence of cardiovascular risk factors and the JAK2 mutational status. The aim of the present study was to assess the clinical and biological characteristics at diagnosis and during evolution in essential thrombocythemia (ET) patients as well as the factors associated with survival and thrombosis and the usefulness of these new prognostic models. We have evaluated the clinical data and the mutation status of JAK2, MPL and calreticulin of 214 ET patients diagnosed in a single center between 1985 and 2012, classified according to classical risk stratification, IPSET and IPSET-Thrombosis. With a median follow-up of 6.9 years, overall survival was not associated with any variable by multivariate analysis. Thrombotic history and leukocytes>10×10(9)/l were associated with thrombosis-free survival (TFS). In our series, IPSET prognostic systems of survival and thrombosis did not provide more clinically relevant information regarding the classic risk of thrombosis stratification. Thrombotic history and leukocytosis>10×10(9)/l were significantly associated with lower TFS, while the prognostic IPSET-Thrombosis system did not provide more information than classical thrombotic risk assessment. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  4. Association study of genetic variants in estrogen metabolic pathway genes and colorectal cancer risk and survival.

    Science.gov (United States)

    Li, Shuwei; Xie, Lisheng; Du, Mulong; Xu, Kaili; Zhu, Lingjun; Chu, Haiyan; Chen, Jinfei; Wang, Meilin; Zhang, Zhengdong; Gu, Dongying

    2018-05-16

    Although studies have investigated the association of genetic variants and the abnormal expression of estrogen-related genes with colorectal cancer risk, the evidence remains inconsistent. We clarified the relationship of genetic variants in estrogen metabolic pathway genes with colorectal cancer risk and survival. A case-control study was performed to assess the association of single-nucleotide polymorphisms (SNPs) in ten candidate genes with colorectal cancer risk in a Chinese population. A logistic regression model and Cox regression model were used to calculate SNP effects on colorectal cancer susceptibility and survival, respectively. Expression quantitative trait loci (eQTL) analysis was conducted using the Genotype-Tissue Expression (GTEx) project dataset. The sequence kernel association test (SKAT) was used to perform gene-set analysis. Colorectal cancer risk and rs3760806 in SULT2B1 were significantly associated in both genders [male: OR = 1.38 (1.15-1.66); female: OR = 1.38 (1.13-1.68)]. Two SNPs in SULT1E1 were related to progression-free survival (PFS) [rs1238574: HR = 1.24 (1.02-1.50), P = 2.79 × 10 -2 ; rs3822172: HR = 1.30 (1.07-1.57), P = 8.44 × 10 -3 ] and overall survival (OS) [rs1238574: HR = 1.51 (1.16-1.97), P = 2.30 × 10 -3 ; rs3822172: HR = 1.53 (1.67-2.00), P = 2.03 × 10 -3 ]. Moreover, rs3760806 was an eQTL for SULT2B1 in colon samples (transverse: P = 3.6 × 10 -3 ; sigmoid: P = 1.0 × 10 -3 ). SULT2B1 expression was significantly higher in colorectal tumor tissues than in normal tissues in the Cancer Genome Atlas (TCGA) database (P colorectal cancer susceptibility and survival.

  5. Pulmonic stenosis in dogs: survival and risk factors in a retrospective cohort of patients.

    Science.gov (United States)

    Locatelli, C; Spalla, I; Domenech, O; Sala, E; Brambilla, P G; Bussadori, C

    2013-09-01

    To assess survival and risk factors in dogs with pulmonic stenosis. A retrospective review of medical case records of all cases of pulmonic stenosis >50 mmHg, undergoing pulmonary balloon valvuloplasty or not. Survival curves and multivariate analysis were calculated in the overall population and in subgroups. One hundred and seventy-two cases were included. Factors negatively affecting survival were clinical signs [hazard ratio (HR) 3 · 44, P Dogs with severe pulmonic stenosis undergoing pulmonary balloon valvuloplasty (HR 0 · 47, P = 0 · 047) and asymptomatic dogs with moderate pulmonic stenosis (HR 0 · 10, P = 0 · 042) had a better outcome. Younger age at diagnosis was correlated with poorer outcome in right-sided congestive heart failure dogs (HR 14 · 02, P = 0 · 01). Clinical signs, valve morphology type B and age at diagnosis are risk factors in pulmonic stenosis patients. Pulmonary balloon valvuloplasty is a reasonable treatment choice in dogs with severe pulmonic stenosis. © 2013 British Small Animal Veterinary Association.

  6. Use of a Survival Analysis Technique in Understanding Game Performance in Instructional Games. CRESST Report 812

    Science.gov (United States)

    Kim, Jinok; Chung, Gregory K. W. K.

    2012-01-01

    In this study we compared the effects of two math game designs on math and game performance, using discrete-time survival analysis (DTSA) to model players' risk of not advancing to the next level in the game. 137 students were randomly assigned to two game conditions. The game covered the concept of a unit and the addition of like-sized fractional…

  7. Environmental risk analysis

    International Nuclear Information System (INIS)

    Lima-e-Silva, Pedro Paulo de

    1996-01-01

    The conventional Risk Analysis (RA) relates usually a certain undesired event frequency with its consequences. Such technique is used nowadays in Brazil to analyze accidents and their consequences strictly under the human approach, valuing loss of human equipment, human structures and human lives, without considering the damage caused to natural resources that keep life possible on Earth. This paradigm was developed primarily because of the Homo sapiens' lack of perception upon the natural web needed to sustain his own life. In reality, the Brazilian professionals responsible today for licensing, auditing and inspecting environmental aspects of human activities face huge difficulties in making technical specifications and procedures leading to acceptable levels of impact, furthermore considering the intrinsic difficulties to define those levels. Therefore, in Brazil the RA technique is a weak tool for licensing for many reasons, and of them are its short scope (only accident considerations) and wrong a paradigm (only human direct damages). A paper from the author about the former was already proposed to the 7th International Conference on Environmetrics, past July'96, USP-SP. This one discusses the extension of the risk analysis concept to take into account environmental consequences, transforming the conventional analysis into a broader methodology named here as Environmental Risk Analysis. (author)

  8. Personalized Prognostic Risk Score for Long-Term Survival for Children with Acute Leukemia after Allogeneic Transplantation.

    Science.gov (United States)

    Bitan, Menachem; Ahn, Kwang Woo; Millard, Heather R; Pulsipher, Michael A; Abdel-Azim, Hisham; Auletta, Jeffery J; Brown, Valerie; Chan, Ka Wah; Diaz, Miguel Angel; Dietz, Andrew; Vincent, Marta González; Guilcher, Gregory; Hale, Gregory A; Hayashi, Robert J; Keating, Amy; Mehta, Parinda; Myers, Kasiani; Page, Kristin; Prestidge, Tim; Shah, Nirali N; Smith, Angela R; Woolfrey, Ann; Thiel, Elizabeth; Davies, Stella M; Eapen, Mary

    2017-09-01

    We studied leukemia-free (LFS) and overall survival (OS) in children with acute myeloid (AML, n = 790) and acute lymphoblastic leukemia (ALL, n = 1096) who underwent transplantation between 2000 and 2010 and who survived for at least 1 year in remission after related or unrelated donor transplantation. Analysis of patient-, disease-, and transplantation characteristics and acute and chronic graft-versus-host disease (GVHD) was performed to identify factors with adverse effects on LFS and OS. These data were used to develop risk scores for survival. We did not identify any prognostic factors beyond 4 years after transplantation for AML and beyond 3 years for ALL. Risk score for survival for AML includes age, disease status at transplantation, cytogenetic risk group, and chronic GVHD. For ALL, the risk score includes age at transplantation and chronic GVHD. The 10-year probabilities of OS for AML with good (score 0, 1, or 2), intermediate (score 3), and poor risk (score 4, 5, 6, or 7) were 94%, 87%, and 68%, respectively. The 10-year probabilities of OS for ALL were 89% and 80% for good (score 0 or 1) and poor risk (score 2), respectively. Identifying children at risk for late mortality with early intervention may mitigate some excess late mortality. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  9. Survival analysis for customer satisfaction: A case study

    Science.gov (United States)

    Hadiyat, M. A.; Wahyudi, R. D.; Sari, Y.

    2017-11-01

    Most customer satisfaction surveys are conducted periodically to track their dynamics. One of the goals of this survey was to evaluate the service design by recognizing the trend of satisfaction score. Many researchers recommended in redesigning the service when the satisfaction scores were decreasing, so that the service life cycle could be predicted qualitatively. However, these scores were usually set in Likert scale and had quantitative properties. Thus, they should also be analyzed in quantitative model so that the predicted service life cycle would be done by applying the survival analysis. This paper discussed a starting point for customer satisfaction survival analysis with a case study in healthcare service.

  10. Statistical models and methods for reliability and survival analysis

    CERN Document Server

    Couallier, Vincent; Huber-Carol, Catherine; Mesbah, Mounir; Huber -Carol, Catherine; Limnios, Nikolaos; Gerville-Reache, Leo

    2013-01-01

    Statistical Models and Methods for Reliability and Survival Analysis brings together contributions by specialists in statistical theory as they discuss their applications providing up-to-date developments in methods used in survival analysis, statistical goodness of fit, stochastic processes for system reliability, amongst others. Many of these are related to the work of Professor M. Nikulin in statistics over the past 30 years. The authors gather together various contributions with a broad array of techniques and results, divided into three parts - Statistical Models and Methods, Statistical

  11. Risk analysis and reliability

    International Nuclear Information System (INIS)

    Uppuluri, V.R.R.

    1979-01-01

    Mathematical foundations of risk analysis are addressed. The importance of having the same probability space in order to compare different experiments is pointed out. Then the following topics are discussed: consequences as random variables with infinite expectations; the phenomenon of rare events; series-parallel systems and different kinds of randomness that could be imposed on such systems; and the problem of consensus of estimates of expert opinion

  12. Multifactorial risk assessment for survival of abutments of removable partial dentures based on practice-based longitudinal study.

    Science.gov (United States)

    Tada, Sayaka; Ikebe, Kazunori; Matsuda, Ken-Ichi; Maeda, Yoshinobu

    2013-12-01

    Predicting the tooth survival is such a great challenge for evidence-based dentistry. To prevent further tooth loss of partially edentulous patients, estimation of individualized risk and benefit for each residual tooth is important to the clinical decision-making. While there are several reports indicating a risk of losing the abutment teeth of RPDs, there are no existing reports exploring the cause of abutment loss by multifactorial analysis. The aim of this practice-based longitudinal study was to determine the prognostic factors affecting the survival period of RPD abutments using a multifactorial risk assessment. One hundred and forty-seven patients had been previously provided with a total of 236 new RPDs at the Osaka University Dental Hospital; the 856 abutments for these RPDs were analyzed. Survival of abutment teeth was estimated using the Kaplan-Meier method. Multivariate analysis was conducted by Cox's proportional hazard modelling. The 5-year survival rates were 86.6% for direct abutments and 93.1% for indirect abutments, compared with 95.8% survival in non-abutment teeth. The multivariate analysis showed that abutment survival was significantly associated with crown-root ratio (hazard ratio (HR): 3.13), root canal treatment (HR: 2.93), pocket depth (HR: 2.51), type of abutments (HR: 2.19) and occlusal support (HR: 1.90). From this practice-based longitudinal study, we concluded that RPD abutment teeth are more likely to be lost than other residual teeth. From the multifactorial risk factor assessment, several prognostic factors, such as occlusal support, crown-root ratio, root canal treatment, and pocket depth were suggested. These results could be used to estimate the individualized risk for the residual teeth, to predict the prognosis of RPD abutments and to facilitate an evidence-based clinical decision making. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. High Genomic Instability Predicts Survival in Metastatic High-Risk Neuroblastoma

    Directory of Open Access Journals (Sweden)

    Sara Stigliani

    2012-09-01

    Full Text Available We aimed to identify novel molecular prognostic markers to better predict relapse risk estimate for children with high-risk (HR metastatic neuroblastoma (NB. We performed genome- and/or transcriptome-wide analyses of 129 stage 4 HR NBs. Children older than 1 year of age were categorized as “short survivors” (dead of disease within 5 years from diagnosis and “long survivors” (alive with an overall survival time ≥ 5 years. We reported that patients with less than three segmental copy number aberrations in their tumor represent a molecularly defined subgroup with a high survival probability within the current HR group of patients. The complex genomic pattern is a prognostic marker independent of NB-associated chromosomal aberrations, i.e., MYCN amplification, 1p and 11q losses, and 17q gain. Integrative analysis of genomic and expression signatures demonstrated that fatal outcome is mainly associated with loss of cell cycle control and deregulation of Rho guanosine triphosphates (GTPases functioning in neuritogenesis. Tumors with MYCN amplification show a lower chromosome instability compared to MYCN single-copy NBs (P = .0008, dominated by 17q gain and 1p loss. Moreover, our results suggest that the MYCN amplification mainly drives disruption of neuronal differentiation and reduction of cell adhesion process involved in tumor invasion and metastasis. Further validation studies are warranted to establish this as a risk stratification for patients.

  14. Surviving a cluster collapse: risk aversion as a core value

    NARCIS (Netherlands)

    Schiele, Holger; Hospers, Gerrit J.; van der Zee, D.J.

    2012-01-01

    Purpose – This paper analyses firms, which survived in a collapsed regional cluster. The target is to analyze whether the principles for enduring success identified researching success factors of very old firms also apply in such an environment. Design/methodology/approach – The authors conduct a

  15. Survival analysis using S analysis of time-to-event data

    CERN Document Server

    Tableman, Mara

    2003-01-01

    Survival Analysis Using S: Analysis of Time-to-Event Data is designed as a text for a one-semester or one-quarter course in survival analysis for upper-level or graduate students in statistics, biostatistics, and epidemiology. Prerequisites are a standard pre-calculus first course in probability and statistics, and a course in applied linear regression models. No prior knowledge of S or R is assumed. A wide choice of exercises is included, some intended for more advanced students with a first course in mathematical statistics. The authors emphasize parametric log-linear models, while also detailing nonparametric procedures along with model building and data diagnostics. Medical and public health researchers will find the discussion of cut point analysis with bootstrap validation, competing risks and the cumulative incidence estimator, and the analysis of left-truncated and right-censored data invaluable. The bootstrap procedure checks robustness of cut point analysis and determines cut point(s). In a chapter ...

  16. Mare Risk Analysis monitor

    International Nuclear Information System (INIS)

    Fuente Prieto, I.; Alonso, P.; Carretero Fernandino, J. A.

    2000-01-01

    The Nuclear Safety Council's requirement that Spanish power plants comply with the requirements of the Maintenance Rule associated with plant risk assessment during power operation, arising from the partial unavailability of systems due to the maintenance activities, has led to need for additional tools to facilitate compliance with said requirements. While the impact on risk produced by individual equipment unavailabilities can easily be evaluated, either qualitatively or quantitatively, the process becomes more complicated when un programmed unavailabilities simultaneously occur in various systems, making it necessary to evaluate their functional impact. It is especially complex in the case of support systems that can affect the functionality of multiple systems. In view of the above, a computer application has been developed that is capable of providing the operator with quick answers based on the specific plant model in order to allow fast risk assessment using the information compiled as part of the Probabilistic Safety Analysis. The paper describes the most important characteristics of this application and the basic design requirements of the MARE Risk Monitor. (Author)

  17. Methods for Risk Analysis

    International Nuclear Information System (INIS)

    Alverbro, Karin

    2010-01-01

    Many decision-making situations today affect humans and the environment. In practice, many such decisions are made without an overall view and prioritise one or other of the two areas. Now and then these two areas of regulation come into conflict, e.g. the best alternative as regards environmental considerations is not always the best from a human safety perspective and vice versa. This report was prepared within a major project with the aim of developing a framework in which both the environmental aspects and the human safety aspects are integrated, and decisions can be made taking both fields into consideration. The safety risks have to be analysed in order to be successfully avoided and one way of doing this is to use different kinds of risk analysis methods. There is an abundance of existing methods to choose from and new methods are constantly being developed. This report describes some of the risk analysis methods currently available for analysing safety and examines the relationships between them. The focus here is mainly on human safety aspects

  18. Causal inference in survival analysis using pseudo-observations

    DEFF Research Database (Denmark)

    Andersen, Per K; Syriopoulou, Elisavet; Parner, Erik T

    2017-01-01

    Causal inference for non-censored response variables, such as binary or quantitative outcomes, is often based on either (1) direct standardization ('G-formula') or (2) inverse probability of treatment assignment weights ('propensity score'). To do causal inference in survival analysis, one needs ...

  19. Effects of non-surgical factors on digital replantation survival rate: a meta-analysis.

    Science.gov (United States)

    Ma, Z; Guo, F; Qi, J; Xiang, W; Zhang, J

    2016-02-01

    This study aimed to evaluate the risk factors affecting survival rate of digital replantation by a meta-analysis. A computer retrieval of MEDLINE, OVID, EMBASE, and CNKI databases was conducted to identify citations for digital replantation with digit or finger or thumb or digital or fingertip and replantation as keywords. RevMan 5.2 software was used to calculate the pooled odds ratios. In total, there were 4678 amputated digits in 2641 patients. Gender and ischemia time had no significant influence on the survival rate of amputation replantation (P > 0.05). Age, injured hand, injury type, zone, and the method of preservation the amputated digit significantly influence the survival rate of digital replantation (P < 0.05). Children, right hand, crush, or avulsion and little finger are the risk factors that adversely affect the outcome. Level 5*. © The Author(s) 2015.

  20. Bernstein - Von Mises theorem and its application in survival analysis

    Czech Academy of Sciences Publication Activity Database

    Timková, Jana

    2010-01-01

    Roč. 22, č. 3 (2010), s. 115-122 ISSN 1210-8022. [16. letní škola JČMF Robust 2010. Králíky, 30.01.2010-05.02.2010] R&D Projects: GA AV ČR(CZ) IAA101120604 Institutional research plan: CEZ:AV0Z10750506 Keywords : Cox model * bayesian asymptotics * survival function Subject RIV: BB - Applied Statistics, Operational Research http://library.utia.cas.cz/separaty/2010/SI/timkova-bernstein - von mises theorem and its application in survival analysis.pdf

  1. A retrospective analysis of survival and prognostic factors after stereotactic radiosurgery for aggressive meningiomas

    International Nuclear Information System (INIS)

    Ferraro, Daniel J; Zoberi, Imran; Simpson, Joseph R; Jaboin, Jerry J; Funk, Ryan K; Blackett, John William; Ju, Michelle R; DeWees, Todd A; Chicoine, Michael R; Dowling, Joshua L; Rich, Keith M; Drzymala, Robert E

    2014-01-01

    predictive of recurrence and survival on multivariate analysis in aggressive meningioma patients treated with radiosurgery. Larger tumor size predicts poor survival, while nuclear atypia, necrosis, and increased mitotic rate are risk factors for recurrence. Clinical and pathologic predictors may help identify patients that are at higher risk for recurrence

  2. Introduction to SURPH.1 analysis of release-recapture data for survival studies

    International Nuclear Information System (INIS)

    Smith, S.G.; Skalski, J.R.; Schlechte, J.W.; Hoffmann, A.; Cassen, V.

    1994-12-01

    Program SURPH is the culmination of several years of research to develop a comprehensive computer program to analyze survival studies of fish and wildlife populations. Development of this software was motivated by the advent of the PIT-tag (Passive Integrated Transponder) technology that permits the detection of salmonid smolt as they pass through hydroelectric facilities on the Snake and Columbia Rivers in the Pacific Northwest. Repeated detections of individually tagged smolt and analysis of their capture-histories permits estimates of downriver survival probabilities. Eventual installation of detection facilities at adult fish ladders will also permit estimation of ocean survival and upstream survival of returning salmon using the statistical methods incorporated in SURPH.1. However, the utility of SURPH.1 far exceeds solely the analysis of salmonid tagging studies. Release-recapture and radiotelemetry studies from a wide range of terrestrial and aquatic species have been analyzed using SURPH.1 to estimate discrete time survival probabilities and investigate survival relationships. The interactive computing environment of SURPH.1 was specifically developed to allow researchers to investigate the relationship between survival and capture processes and environmental, experimental and individual-based covariates. Program SURPH.1 represents a significant advancement in the ability of ecologists to investigate the interplay between morphologic, genetic, environmental and anthropogenic factors on the survival of wild species. It is hoped that this better understanding of risk factors affecting survival will lead to greater appreciation of the intricacies of nature and to improvements in the management of wild resources. This technical report is an introduction to SURPH.1 and provides a user guide for both the UNIX and MS-Windows reg-sign applications of the SURPH software

  3. Coding variants in NOD-like receptors: An association study on risk and survival of colorectal cancer.

    Science.gov (United States)

    Huhn, Stefanie; da Silva Filho, Miguel I; Sanmuganantham, Tharmila; Pichulik, Tica; Catalano, Calogerina; Pardini, Barbara; Naccarati, Alessio; Polakova-Vymetálkova, Veronika; Jiraskova, Katerina; Vodickova, Ludmila; Vodicka, Pavel; Löffler, Markus W; Courth, Lioba; Wehkamp, Jan; Din, Farhat V N; Timofeeva, Maria; Farrington, Susan M; Jansen, Lina; Hemminki, Kari; Chang-Claude, Jenny; Brenner, Hermann; Hoffmeister, Michael; Dunlop, Malcolm G; Weber, Alexander N R; Försti, Asta

    2018-01-01

    Nod-like receptors (NLRs) are important innate pattern recognition receptors and regulators of inflammation or play a role during development. We systematically analysed 41 non-synonymous single nucleotide polymorphisms (SNPs) in 21 NLR genes in a Czech discovery cohort of sporadic colorectal cancer (CRC) (1237 cases, 787 controls) for their association with CRC risk and survival. Five SNPs were found to be associated with CRC risk and eight with survival at 5% significance level. In a replication analysis using data of two large genome-wide association studies (GWASs) from Germany (DACHS: 1798 cases and 1810 controls) and Scotland (2210 cases and 9350 controls) the associations found in the Czech discovery set were not confirmed. However, expression analysis in human gut-related tissues and immune cells revealed that the NLRs associated with CRC risk or survival in the discovery set were expressed in primary human colon or rectum cells, CRC tissue and/or cell lines, providing preliminary evidence for a potential involvement of NLRs in general in CRC development and/or progression. Most interesting was the finding that the enigmatic development-related NLRP5 (also known as MATER) was not expressed in normal colon tissue but in colon cancer tissue and cell lines. Future studies may show whether regulatory variants instead of coding variants might affect the expression of NLRs and contribute to CRC risk and survival.

  4. Direct Survival Analysis: a new stock assessment method

    Directory of Open Access Journals (Sweden)

    Eduardo Ferrandis

    2007-03-01

    Full Text Available In this work, a new stock assessment method, Direct Survival Analysis, is proposed and described. The parameter estimation of the Weibull survival model proposed by Ferrandis (2007 is obtained using trawl survey data. This estimation is used to establish a baseline survival function, which is in turn used to estimate the specific survival functions in the different cohorts considered through an adaptation of the separable model of the fishing mortality rates introduced by Pope and Shepherd (1982. It is thus possible to test hypotheses on the evolution of survival during the period studied and to identify trends in recruitment. A link is established between the preceding analysis of trawl survey data and the commercial catch-at-age data that are generally obtained to evaluate the population using analytical models. The estimated baseline survival, with the proposed versions of the stock and catch equations and the adaptation of the Separable Model, may be applied to commercial catch-at-age data. This makes it possible to estimate the survival corresponding to the landing data, the initial size of the cohort and finally, an effective age of first capture, in order to complete the parameter model estimation and consequently the estimation of the whole survival and mortality, along with the reference parameters that are useful for management purposes. Alternatively, this estimation of an effective age of first capture may be obtained by adapting the demographic structure of trawl survey data to that of the commercial fleet through suitable selectivity models of the commercial gears. The complete model provides the evaluation of the stock at any age. The coherence (and hence the mutual “calibration” between the two kinds of information may be analysed and compared with results obtained by other methods, such as virtual population analysis (VPA, in order to improve the diagnosis of the state of exploitation of the population. The model may be

  5. 'Enterprise risk management' essential for survival and sustainable development of micro, small and medium enterprises

    OpenAIRE

    Agrawal Reena

    2016-01-01

    The part that Micro, Small and Medium Enterprises (MSMEs) play, both in developed and developing countries, cannot be over emphasized and therefore their existence and survival is a matter of concern not only for the policy makers but also for the researchers. Large number of MSMEs die the same year that they are established. The current research was taken up to understand how MSMEs manage their risk and whether enterprise risk management is essential for survival and sustainable development ...

  6. Fatores de risco para óbito em unidade de terapia intensiva neonatal, utilizando a técnica de análise de sobrevida Risk factors for neonatal death in neonatal intensive care unit according to survival analysis

    Directory of Open Access Journals (Sweden)

    Susana de Paula Risso

    2010-03-01

    ; hospitalar variables: report of mechanical ventilation, positive pressure ventilation, reports of prolonged parenteral nutrition, sepsis, intubation, cardiac massage, phototherapy, hyaline membrane disease, oxygen and fraction of inspired oxygen. It was built a model in three hierarchical levels for the survival analysis by the Cox model; it was used the software Stata v9 and the final model contained variables with p <0.05. The risks were estimated by measure effect known as hazard ratio (HR with confidence intervals of 95%. The newborns transferred during hospitalization to another service were excluded from the study. RESULTS: There were admitted during the study period 495 newborns, with 129 deaths (26.1%. In the final model, only the variables of steroid use (HR 1.64, 95% CI 1.02-2.70, malformation (HR 1.93, CI 95% 1,05-2,88, very low birth weight (HR 4.28, 95% CI 2,79-6,57 and Apgar scores lower than seven of no1 min (HR 1.87, 95% CI 1,19-2,93 and 5 min (HR 1.74, 95% CI 1,05-2,88 and the variables phototherapy (HR 0.34; 95% CI 0,22-0,53 and endotracheal intubation (HR 2.28, 95% CI 1 .41-3, 70. CONCLUSION: Factors related primarily to the newborn and the hospitalar internment (except therapy with corticosteroids were identified as associated to mortality highlighting a possible protective factor of phototherapy and the risk of infants with very low birth weight.

  7. Probabilistic risk analysis and terrorism risk.

    Science.gov (United States)

    Ezell, Barry Charles; Bennett, Steven P; von Winterfeldt, Detlof; Sokolowski, John; Collins, Andrew J

    2010-04-01

    Since the terrorist attacks of September 11, 2001, and the subsequent establishment of the U.S. Department of Homeland Security (DHS), considerable efforts have been made to estimate the risks of terrorism and the cost effectiveness of security policies to reduce these risks. DHS, industry, and the academic risk analysis communities have all invested heavily in the development of tools and approaches that can assist decisionmakers in effectively allocating limited resources across the vast array of potential investments that could mitigate risks from terrorism and other threats to the homeland. Decisionmakers demand models, analyses, and decision support that are useful for this task and based on the state of the art. Since terrorism risk analysis is new, no single method is likely to meet this challenge. In this article we explore a number of existing and potential approaches for terrorism risk analysis, focusing particularly on recent discussions regarding the applicability of probabilistic and decision analytic approaches to bioterrorism risks and the Bioterrorism Risk Assessment methodology used by the DHS and criticized by the National Academies and others.

  8. Survival analysis in hematologic malignancies: recommendations for clinicians

    Science.gov (United States)

    Delgado, Julio; Pereira, Arturo; Villamor, Neus; López-Guillermo, Armando; Rozman, Ciril

    2014-01-01

    The widespread availability of statistical packages has undoubtedly helped hematologists worldwide in the analysis of their data, but has also led to the inappropriate use of statistical methods. In this article, we review some basic concepts of survival analysis and also make recommendations about how and when to perform each particular test using SPSS, Stata and R. In particular, we describe a simple way of defining cut-off points for continuous variables and the appropriate and inappropriate uses of the Kaplan-Meier method and Cox proportional hazard regression models. We also provide practical advice on how to check the proportional hazards assumption and briefly review the role of relative survival and multiple imputation. PMID:25176982

  9. Percutaneous radiofrequency ablation for early hepatocellular carcinoma: Risk factors for survival

    Science.gov (United States)

    Kikuchi, Luciana; Menezes, Marcos; Chagas, Aline L; Tani, Claudia M; Alencar, Regiane SSM; Diniz, Marcio A; Alves, Venâncio AF; D’Albuquerque, Luiz Augusto Carneiro; Carrilho, Flair José

    2014-01-01

    AIM: To evaluate outcomes of radiofrequency ablation (RFA) therapy for early hepatocellular carcinoma (HCC) and identify survival- and recurrence-related factors. METHODS: Consecutive patients diagnosed with early HCC by computed tomography (CT) or magnetic resonance imaging (MRI) (single nodule of ≤ 5 cm, or multi- (up to 3) nodules of ≤ 3 cm each) and who underwent RFA treatment with curative intent between January 2010 and August 2011 at the Instituto do Câncer do Estado de São Paulo, Brazil were enrolled in the study. RFA of the liver tumors (with 1.0 cm ablative margin) was carried out under CT-fluoro scan and ultrasonic image guidance of the percutaneous ablation probes. Procedure-related complications were recorded. At 1-mo post-RFA and 3-mo intervals thereafter, CT and MRI were performed to assess outcomes of complete response (absence of enhancing tissue at the tumor site) or incomplete response (enhancing tissue remaining at the tumor site). Overall survival and disease-free survival rates were estimated by the Kaplan-Meier method and compared by the log rank test or simple Cox regression. The effect of risk factors on survival was assessed by the Cox proportional hazard model. RESULTS: A total of 38 RFA sessions were performed during the study period on 34 patients (age in years: mean, 63 and range, 49-84). The mean follow-up time was 22 mo (range, 1-33). The study population showed predominance of male sex (76%), less severe liver disease (Child-Pugh A, n = 26; Child-Pugh B, n = 8), and single tumor (65%). The maximum tumor diameters ranged from 10 to 50 mm (median, 26 mm). The initial (immediately post-procedure) rate of RFA-induced complete tumor necrosis was 90%. The probability of achieving complete response was significantly greater in patients with a single nodule (vs patients with multi-nodules, P = 0.04). Two patients experienced major complications, including acute pulmonary edema (resolved with intervention) and intestinal perforation

  10. Successful survival, growth, and reproductive potential of quagga mussels in low calcium lake water: is there uncertainty of establishment risk?

    Directory of Open Access Journals (Sweden)

    Clinton J. Davis

    2015-11-01

    Full Text Available The risk of quagga mussel (Dreissena rostriformis bugensis Andrusov 1897 establishment into water-bodies of the western US has expanded the geographic concern regarding the ecological and economic impacts this species will have in aquatic ecosystems. Thresholds based on calcium concentrations, an element critical for mussel growth and physiology, have been used as a primary predictor of quagga mussel establishment success to aid management decisions. We evaluated the invasion potential of quagga mussels in low calcium waters using laboratory experiments to compare the survival, growth and reproductive potential of adult mussels held for 90 days at low (9 and 12 ppm, moderate (15 to 32 ppm and high (72 ppm calcium water concentrations. In conjunction with adult experiments, veliger stage survival, growth and settlement were evaluated under similar low, moderate, and high calcium water treatments. Adult mussels survived, grew and showed reproductive potential in low calcium water (12 ppm. Veligers were also able to survive, grow and settle in low calcium water. Higher levels of natural seston biomass appeared to improve adult mussel life history performance in low calcium water. Survival curve analysis predicted that 99% adult mortality could occur in 15 ppm could have adults surviving more than a year. The results from these bioassays provide further evidence that quagga mussels have higher risk of establishment in low calcium lakes if habitats exist that have slightly elevated calcium. These results should help emphasize the vulnerability of water-body in the 12 to 15 ppm calcium range that could potentially be at risk of establishing sustainable quagga mussel populations. Furthermore, these results provide insights into the uncertainty of using a single parameter in assigning establishment risk given the complexity of variables in specific water-bodies that influence life history performance of introduced species.

  11. Successful survival, growth, and reproductive potential of quagga mussels in low calcium lake water: is there uncertainty of establishment risk?

    Science.gov (United States)

    Davis, Clinton J; Ruhmann, Emma K; Acharya, Kumud; Chandra, Sudeep; Jerde, Christopher L

    2015-01-01

    The risk of quagga mussel (Dreissena rostriformis bugensis Andrusov 1897) establishment into water-bodies of the western US has expanded the geographic concern regarding the ecological and economic impacts this species will have in aquatic ecosystems. Thresholds based on calcium concentrations, an element critical for mussel growth and physiology, have been used as a primary predictor of quagga mussel establishment success to aid management decisions. We evaluated the invasion potential of quagga mussels in low calcium waters using laboratory experiments to compare the survival, growth and reproductive potential of adult mussels held for 90 days at low (9 and 12 ppm), moderate (15 to 32 ppm) and high (72 ppm) calcium water concentrations. In conjunction with adult experiments, veliger stage survival, growth and settlement were evaluated under similar low, moderate, and high calcium water treatments. Adult mussels survived, grew and showed reproductive potential in low calcium water (12 ppm). Veligers were also able to survive, grow and settle in low calcium water. Higher levels of natural seston biomass appeared to improve adult mussel life history performance in low calcium water. Survival curve analysis predicted that 99% adult mortality could occur in 15 ppm could have adults surviving more than a year. The results from these bioassays provide further evidence that quagga mussels have higher risk of establishment in low calcium lakes if habitats exist that have slightly elevated calcium. These results should help emphasize the vulnerability of water-body in the 12 to 15 ppm calcium range that could potentially be at risk of establishing sustainable quagga mussel populations. Furthermore, these results provide insights into the uncertainty of using a single parameter in assigning establishment risk given the complexity of variables in specific water-bodies that influence life history performance of introduced species.

  12. BEHAVIORAL DECISION-THEORY AND ENVIRONMENTAL RISK MANAGEMENT - ASSESSMENT AND RESOLUTION OF 4 SURVIVAL DILEMMAS

    NARCIS (Netherlands)

    VLEK, C; KEREN, G

    Environmental degradation and the call for 'sustainable development' provide an extended context and new challenges for decision-theoretic research on risk assessment and management. We characterize environmental risk management as the resolution of four different types of 'survival' dilemmas in

  13. Mortality risk and survival in the aftermath of the medieval Black Death.

    Science.gov (United States)

    DeWitte, Sharon N

    2014-01-01

    The medieval Black Death (c. 1347-1351) was one of the most devastating epidemics in human history. It killed tens of millions of Europeans, and recent analyses have shown that the disease targeted elderly adults and individuals who had been previously exposed to physiological stressors. Following the epidemic, there were improvements in standards of living, particularly in dietary quality for all socioeconomic strata. This study investigates whether the combination of the selective mortality of the Black Death and post-epidemic improvements in standards of living had detectable effects on survival and mortality in London. Samples are drawn from several pre- and post-Black Death London cemeteries. The pre-Black Death sample comes from the Guildhall Yard (n = 75) and St. Nicholas Shambles (n = 246) cemeteries, which date to the 11th-12th centuries, and from two phases within the St. Mary Spital cemetery, which date to between 1120-1300 (n = 143). The St. Mary Graces cemetery (n = 133) was in use from 1350-1538 and thus represents post-epidemic demographic conditions. By applying Kaplan-Meier analysis and the Gompertz hazard model to transition analysis age estimates, and controlling for changes in birth rates, this study examines differences in survivorship and mortality risk between the pre- and post-Black Death populations of London. The results indicate that there are significant differences in survival and mortality risk, but not birth rates, between the two time periods, which suggest improvements in health following the Black Death, despite repeated outbreaks of plague in the centuries after the Black Death.

  14. Mortality risk and survival in the aftermath of the medieval Black Death.

    Directory of Open Access Journals (Sweden)

    Sharon N DeWitte

    Full Text Available The medieval Black Death (c. 1347-1351 was one of the most devastating epidemics in human history. It killed tens of millions of Europeans, and recent analyses have shown that the disease targeted elderly adults and individuals who had been previously exposed to physiological stressors. Following the epidemic, there were improvements in standards of living, particularly in dietary quality for all socioeconomic strata. This study investigates whether the combination of the selective mortality of the Black Death and post-epidemic improvements in standards of living had detectable effects on survival and mortality in London. Samples are drawn from several pre- and post-Black Death London cemeteries. The pre-Black Death sample comes from the Guildhall Yard (n = 75 and St. Nicholas Shambles (n = 246 cemeteries, which date to the 11th-12th centuries, and from two phases within the St. Mary Spital cemetery, which date to between 1120-1300 (n = 143. The St. Mary Graces cemetery (n = 133 was in use from 1350-1538 and thus represents post-epidemic demographic conditions. By applying Kaplan-Meier analysis and the Gompertz hazard model to transition analysis age estimates, and controlling for changes in birth rates, this study examines differences in survivorship and mortality risk between the pre- and post-Black Death populations of London. The results indicate that there are significant differences in survival and mortality risk, but not birth rates, between the two time periods, which suggest improvements in health following the Black Death, despite repeated outbreaks of plague in the centuries after the Black Death.

  15. Clinicopathological analysis of recurrence patterns and prognostic factors for survival after hepatectomy for colorectal liver metastasis

    Directory of Open Access Journals (Sweden)

    Okuda Junji

    2010-09-01

    Full Text Available Abstract Background Hepatectomy is recommended as the most effective therapy for liver metastasis from colorectal cancer (CRCLM. It is crucial to elucidate the prognostic clinicopathological factors. Methods Eighty-three patients undergoing initial hepatectomy for CRCLM were retrospectively analyzed with respect to characteristics of primary colorectal and metastatic hepatic tumors, operation details and prognosis. Results The overall 5-year survival rate after initial hepatectomy for CRCLM was 57.5%, and the median survival time was 25 months. Univariate analysis clarified that the significant prognostic factors for poor survival were depth of primary colorectal cancer (≥ serosal invasion, hepatic resection margin ( Conclusions Optimal surgical strategies in conjunction with effective chemotherapeutic regimens need to be established in patients with risk factors for recurrence and poor outcomes as listed above.

  16. Evaluating disease management program effectiveness: an introduction to survival analysis.

    Science.gov (United States)

    Linden, Ariel; Adams, John L; Roberts, Nancy

    2004-01-01

    Currently, the most widely used method in the disease management industry for evaluating program effectiveness is the "total population approach." This model is a pretest-posttest design, with the most basic limitation being that without a control group, there may be sources of bias and/or competing extraneous confounding factors that offer plausible rationale explaining the change from baseline. Survival analysis allows for the inclusion of data from censored cases, those subjects who either "survived" the program without experiencing the event (e.g., achievement of target clinical levels, hospitalization) or left the program prematurely, due to disenrollement from the health plan or program, or were lost to follow-up. Additionally, independent variables may be included in the model to help explain the variability in the outcome measure. In order to maximize the potential of this statistical method, validity of the model and research design must be assured. This paper reviews survival analysis as an alternative, and more appropriate, approach to evaluating DM program effectiveness than the current total population approach.

  17. Risk-adjusted survival after tissue versus mechanical aortic valve replacement: a 23-year assessment.

    Science.gov (United States)

    Gaca, Jeffrey G; Clare, Robert M; Rankin, J Scott; Daneshmand, Mani A; Milano, Carmelo A; Hughes, G Chad; Wolfe, Walter G; Glower, Donald D; Smith, Peter K

    2013-11-01

    Detailed analyses of risk-adjusted outcomes after mitral valve surgery have documented significant survival decrements with tissue valves at any age. Several recent studies of prosthetic aortic valve replacement (AVR) also have suggested a poorer performance of tissue valves, although analyses have been limited to small matched series. The study aim was to test the hypothesis that AVR with tissue valves is associated with a lower risk-adjusted survival, as compared to mechanical valves. Between 1986 and 2009, primary isolated AVR, with or without coronary artery bypass grafting (CABG), was performed with currently available valve types in 2148 patients (1108 tissue valves, 1040 mechanical). Patients were selected for tissue valves to be used primarily in the elderly. Baseline and operative characteristics were documented prospectively with a consistent variable set over the entire 23-year period. Follow up was obtained with mailed questionnaires, supplemented by National Death Index searches. The average time to death or follow up was seven years, and follow up for survival was 96.2% complete. Risk-adjusted survival characteristics for the two groups were evaluated using a Cox proportional hazards model with stepwise selection of candidate variables. Differences in baseline characteristics between groups were (tissue versus mechanical): median age 73 versus 61 years; non-elective surgery 32% versus 28%; CABG 45% versus 35%; median ejection fraction 55% versus 55%; renal failure 6% versus 1%; diabetes 18% versus 7% (pvalves; however, after risk adjustment for the adverse profiles of tissue valve patients, no significant difference was observed in survival after tissue or mechanical AVR. Thus, the hypothesis did not hold, and risk-adjusted survival was equivalent, of course qualified by the fact that selection bias was evident. With selection criteria that employed tissue AVR more frequently in elderly patients, tissue and mechanical valves achieved similar survival

  18. 'Enterprise risk management' essential for survival and sustainable development of micro, small and medium enterprises

    Directory of Open Access Journals (Sweden)

    Agrawal Reena

    2016-01-01

    Full Text Available The part that Micro, Small and Medium Enterprises (MSMEs play, both in developed and developing countries, cannot be over emphasized and therefore their existence and survival is a matter of concern not only for the policy makers but also for the researchers. Large number of MSMEs die the same year that they are established. The current research was taken up to understand how MSMEs manage their risk and whether enterprise risk management is essential for survival and sustainable development of MSMEs. The objective of the research was to (1 understand the peculiar nature of the MSMEs which make them vulnerable, (2 explore the various risks confronted by MSMEs, (3 understand how the MSMEs manage their risk, (4 understand 'Enterprise Risk Management' and its components and (5 explore the relevance of 'Enterprise Risk Management' for the survival and sustainable development of MSMEs. The results show that MSMEs by virtue of their size, inadequate resources and restricted know-how generally confront wide-ranging risks. In MSMEs the management of risk is concentrated in the hands of the owner-managers and there are no systemic linkages between the planning and risk management. Therefore, this study stresses the need for integrating an effective enterprise risk management system with planning and administration within the MSMEs, to avoid fatal consequences.

  19. Multivariate Survival Mixed Models for Genetic Analysis of Longevity Traits

    DEFF Research Database (Denmark)

    Pimentel Maia, Rafael; Madsen, Per; Labouriau, Rodrigo

    2014-01-01

    A class of multivariate mixed survival models for continuous and discrete time with a complex covariance structure is introduced in a context of quantitative genetic applications. The methods introduced can be used in many applications in quantitative genetics although the discussion presented co...... applications. The methods presented are implemented in such a way that large and complex quantitative genetic data can be analyzed......A class of multivariate mixed survival models for continuous and discrete time with a complex covariance structure is introduced in a context of quantitative genetic applications. The methods introduced can be used in many applications in quantitative genetics although the discussion presented...... concentrates on longevity studies. The framework presented allows to combine models based on continuous time with models based on discrete time in a joint analysis. The continuous time models are approximations of the frailty model in which the hazard function will be assumed to be piece-wise constant...

  20. Multivariate Survival Mixed Models for Genetic Analysis of Longevity Traits

    DEFF Research Database (Denmark)

    Pimentel Maia, Rafael; Madsen, Per; Labouriau, Rodrigo

    2013-01-01

    A class of multivariate mixed survival models for continuous and discrete time with a complex covariance structure is introduced in a context of quantitative genetic applications. The methods introduced can be used in many applications in quantitative genetics although the discussion presented co...... applications. The methods presented are implemented in such a way that large and complex quantitative genetic data can be analyzed......A class of multivariate mixed survival models for continuous and discrete time with a complex covariance structure is introduced in a context of quantitative genetic applications. The methods introduced can be used in many applications in quantitative genetics although the discussion presented...... concentrates on longevity studies. The framework presented allows to combine models based on continuous time with models based on discrete time in a joint analysis. The continuous time models are approximations of the frailty model in which the hazard function will be assumed to be piece-wise constant...

  1. International Conference on Risk Analysis

    CERN Document Server

    Oliveira, Teresa; Rigas, Alexandros; Gulati, Sneh

    2015-01-01

    This book covers the latest results in the field of risk analysis. Presented topics include probabilistic models in cancer research, models and methods in longevity, epidemiology of cancer risk, engineering reliability and economical risk problems. The contributions of this volume originate from the 5th International Conference on Risk Analysis (ICRA 5). The conference brought together researchers and practitioners working in the field of risk analysis in order to present new theoretical and computational methods with applications in biology, environmental sciences, public health, economics and finance.

  2. Risk Factors Associated With Survival to Hospital Discharge of 54 Horses With Fractures of the Radius.

    Science.gov (United States)

    Stewart, Suzanne; Richardson, Dean; Boston, Ray; Schaer, Thomas P

    2015-11-01

    To determine (1) survival to discharge of horses with radial fractures (excluding osteochondral fragmentation of the distal aspect of the radius and stress fractures); and (2) risk factors affecting survival to hospital discharge in conservative and surgically managed fractures. Case series. Horses (n = 54). Medical records (1990-June 2012) and radiographs of horses admitted with radial fracture were reviewed. Horses with osteochondral fragmentation of the distal aspect of the radius or stress fractures were excluded. Evaluated risk factors were age, fracture configuration, surgical repair method, surgical duration, hospitalization time, implant failure rate, and surgical site infection (SSI) rate. Of 54 horses, overall survival to discharge was 50%. Thirteen (24%) were euthanatized on admission because of (1) fracture severity; (2) presence of an open fracture; or (3) financial constraints. Fourteen (26%) horses with minimally displaced incomplete fractures were conservatively managed and 12 (86%) survived to discharge. Twenty-seven (50%) horses had surgical treatment by open reduction and internal fixation (ORIF) and 15 (56%) survived to hospital discharge. Open fractures were significantly more likely to develop SSI (P = .008), which also resulted in a 17-fold increase in implant failure (P horses with an open fracture did not survive to discharge. Outcome was also adversely affected by age (P 168 minutes (P fractures is good. Young horses have a good prognosis survival to discharge for ORIF, whereas ORIF in adult horses has a poor prognosis and SSI strongly correlates with catastrophic implant failure. © Copyright 2015 by The American College of Veterinary Surgeons.

  3. Decitabine improves progression-free survival in older high-risk MDS patients with multiple autosomal monosomies: results of a subgroup analysis of the randomized phase III study 06011 of the EORTC Leukemia Cooperative Group and German MDS Study Group.

    Science.gov (United States)

    Lübbert, Michael; Suciu, Stefan; Hagemeijer, Anne; Rüter, Björn; Platzbecker, Uwe; Giagounidis, Aristoteles; Selleslag, Dominik; Labar, Boris; Germing, Ulrich; Salih, Helmut R; Muus, Petra; Pflüger, Karl-Heinz; Schaefer, Hans-Eckart; Bogatyreva, Lioudmila; Aul, Carlo; de Witte, Theo; Ganser, Arnold; Becker, Heiko; Huls, Gerwin; van der Helm, Lieke; Vellenga, Edo; Baron, Frédéric; Marie, Jean-Pierre; Wijermans, Pierre W

    2016-01-01

    In a study of elderly AML patients treated with the hypomethylating agent decitabine (DAC), we noted a surprisingly favorable outcome in the (usually very unfavorable) subgroup with two or more autosomal monosomies (MK2+) within a complex karyotype (Lübbert et al., Haematologica 97:393-401, 2012). We now analyzed 206 myelodysplastic syndrome (MDS) patients (88 % of 233 patients randomized in the EORTC/GMDSSG phase III trial 06011, 61 of them with RAEBt, i.e. AML by WHO) with cytogenetics informative for MK status.. Endpoints are the following: complete/partial (CR/PR) and overall response rate (ORR) and progression-free (PFS) and overall survival (OS). Cytogenetic subgroups are the following: 63 cytogenetically normal (CN) patients, 143 with cytogenetic abnormalities, 73 of them MK-negative (MK-), and 70 MK-positive (MK+). These MK+ patients could be divided into 17 with a single autosomal monosomy (MK1) and 53 with at least two monosomies (MK2+). ORR with DAC in CN patients: 36.1 %, in MK- patients: 16.7 %, in MK+ patients: 43.6 % (MK1: 44.4 %, MK2+ 43.3 %). PFS was prolonged by DAC compared to best supportive care (BSC) in the CN (hazard ratio (HR) 0.55, 99 % confidence interval (CI), 0.26; 1.15, p = 0.03) and MK2+ (HR 0.50; 99 % CI, 0.23; 1.06, p = 0.016) but not in the MK-, MK+, and MK1 subgroups. OS was not improved by DAC in any subgroup. In conclusion, we demonstrate for the first time in a randomized phase III trial that high-risk MDS patients with complex karyotypes harboring two or more autosomal monosomies attain encouraging responses and have improved PFS with DAC treatment compared to BSC.

  4. Acute myeloid leukaemia: expression of MYC protein and its association with cytogenetic risk profile and overall survival.

    Science.gov (United States)

    Mughal, Muhammad Kashif; Akhter, Ariz; Street, Lesley; Pournazari, Payam; Shabani-Rad, Meer-Taher; Mansoor, Adnan

    2017-09-01

    Acute myeloid leukaemia (AML) is a clinically aggressive disease with marked genetic heterogeneity. Cytogenetic abnormalities provide the basis for risk stratification into clinically favourable, intermediate, and unfavourable groups. There are additional genetic mutations, which further influence the prognosis of patients with AML. Most of these result in molecular aberrations whose downstream target is MYC. It is therefore logical to study the relationship between MYC protein expression and cytogenetic risk groups. We studied MYC expression by immunohistochemistry in a large cohort (n = 199) of AML patients and correlated these results with cytogenetic risk profile and overall survival (OS). We illustrated differential expression of MYC protein across various cytogenetic risk groups (p = 0.03). Highest expression of MYC was noted in AML patients with favourable cytogenetic risk group. In univariate analysis, MYC expression showed significant negative influence of OS in favourable and intermediate cytogenetic risk group (p = 0.001). Interestingly, MYC expression had a protective effect in the unfavourable cytogenetic risk group. In multivariate analysis, while age and cytogenetic risk group were significant factors influencing survival, MYC expression by immunohistochemistry methods also showed some marginal impact (p = 0.069). In conclusion, we have identified differential expression of MYC protein in relation to cytogenetic risk groups in AML patients and documented its possible impact on OS in favourable and intermediate cytogenetic risk groups. These preliminary observations mandate additional studies to further investigate the routine clinical use of MYC protein expression in AML risk stratification. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  5. Jaundice: an important, poorly recognized risk factor for diminished survival in patients with adenocarcinoma of the head of the pancreas

    Science.gov (United States)

    Strasberg, Steven M; Gao, Feng; Sanford, Dominic; Linehan, David C; Hawkins, William G; Fields, Ryan; Carpenter, Danielle H; Brunt, Elizabeth M; Phillips, Carolyn

    2014-01-01

    Objectives: Jaundice impairs cellular immunity, an important defence against the dissemination of cancer. Jaundice is a common mode of presentation in pancreatic head adenocarcinoma. The purpose of this study was to determine whether there is an association between preoperative jaundice and survival in patients who have undergone resection of such tumours. Methods: Thirty possible survival risk factors were evaluated in a database of over 400 resected patients. Univariate analysis was used to determine odds ratio for death. All factors for which a P-value of jaundice, age, positive node status, poor differentiation and lymphatic invasion were significant indicators of poor outcome in multivariate analysis. Absence of jaundice was a highly favourable prognostic factor. Interaction emerged between jaundice and nodal status. The benefit conferred by the absence of jaundice was restricted to patients in whom negative node status was present. Five-year overall survival in this group was 66%. Jaundiced patients who underwent preoperative stenting had a survival advantage. Conclusions: Preoperative jaundice is a negative risk factor in adenocarcinoma of the pancreas. Additional studies are required to determine the exact mechanism for this effect. PMID:23600768

  6. Multilevel survival analysis of health inequalities in life expectancy

    Directory of Open Access Journals (Sweden)

    Merlo Juan

    2009-08-01

    Full Text Available Abstract Background The health status of individuals is determined by multiple factors operating at both micro and macro levels and the interactive effects of them. Measures of health inequalities should reflect such determinants explicitly through sources of levels and combining mean differences at group levels and the variation of individuals, for the benefits of decision making and intervention planning. Measures derived recently from marginal models such as beta-binomial and frailty survival, address this issue to some extent, but are limited in handling data with complex structures. Beta-binomial models were also limited in relation to measuring inequalities of life expectancy (LE directly. Methods We propose a multilevel survival model analysis that estimates life expectancy based on survival time with censored data. The model explicitly disentangles total health inequalities in terms of variance components of life expectancy compared to the source of variation at the level of individuals in households and parishes and so on, and estimates group differences of inequalities at the same time. Adjusted distributions of life expectancy by gender and by household socioeconomic level are calculated. Relative and absolute health inequality indices are derived based on model estimates. The model based analysis is illustrated on a large Swedish cohort of 22,680 men and 26,474 women aged 65–69 in 1970 and followed up for 30 years. Model based inequality measures are compared to the conventional calculations. Results Much variation of life expectancy is observed at individual and household levels. Contextual effects at Parish and Municipality level are negligible. Women have longer life expectancy than men and lower inequality. There is marked inequality by the level of household socioeconomic status measured by the median life expectancy in each socio-economic group and the variation in life expectancy within each group. Conclusion Multilevel

  7. Survival analysis of dialysis patients in selected hospitals of lahore city

    International Nuclear Information System (INIS)

    Ahmad, Z.; Shahzad, I.

    2015-01-01

    There are several reasons which are directly or indirectly relate to affect the survival time of End Stage Renal Disease (ESRD) patients. This study was done to analyse the survival rate of ESRD patients in Lahore city, and to evaluate the influence of various risk factors and prognostic factors on survival of these patients. Methods: A sample of 40 patients was taken from the Jinnah Hospital Lahore and Lahore General Hospital by using the convenience sampling technique. The Log Rank Test was used to determine the significant difference between the categories of qualitative variables of ESRD patients. Multivariate Cox Regression Analysis was used to analyse the effect of different clinical and socio-economic variables on the survival time of these patients. Results: Different qualitative variables like: age, marital status, BMI, comorbid factors, diabetes type, gender, income level, place, risk factor like diabetes, ischemic heart disease, hypertension and Hepatitis status were analysed on the basis of Log Rank Test. While age and comorbid factors were found to be statistically significant which showed that the distribution of age and comorbid factors were different. By using the Cox Regression analysis the coefficient of Mass, serum albumin and family history of diabetes were found to be significant. Conclusions: There were some of the factors which had been taken for the analysis came out less or more significant in patients of ESRD. So it was concluded that mostly clinical factors which were Mass of the Patient, Serum Albumin and Family History of Diabetes made significant contribution towards the survival status of patients. (author)

  8. Long-Term Survival Prediction for Coronary Artery Bypass Grafting: Validation of the ASCERT Model Compared With The Society of Thoracic Surgeons Predicted Risk of Mortality.

    Science.gov (United States)

    Lancaster, Timothy S; Schill, Matthew R; Greenberg, Jason W; Ruaengsri, Chawannuch; Schuessler, Richard B; Lawton, Jennifer S; Maniar, Hersh S; Pasque, Michael K; Moon, Marc R; Damiano, Ralph J; Melby, Spencer J

    2018-05-01

    The recently developed American College of Cardiology Foundation-Society of Thoracic Surgeons (STS) Collaboration on the Comparative Effectiveness of Revascularization Strategy (ASCERT) Long-Term Survival Probability Calculator is a valuable addition to existing short-term risk-prediction tools for cardiac surgical procedures but has yet to be externally validated. Institutional data of 654 patients aged 65 years or older undergoing isolated coronary artery bypass grafting between 2005 and 2010 were reviewed. Predicted survival probabilities were calculated using the ASCERT model. Survival data were collected using the Social Security Death Index and institutional medical records. Model calibration and discrimination were assessed for the overall sample and for risk-stratified subgroups based on (1) ASCERT 7-year survival probability and (2) the predicted risk of mortality (PROM) from the STS Short-Term Risk Calculator. Logistic regression analysis was performed to evaluate additional perioperative variables contributing to death. Overall survival was 92.1% (569 of 597) at 1 year and 50.5% (164 of 325) at 7 years. Calibration assessment found no significant differences between predicted and actual survival curves for the overall sample or for the risk-stratified subgroups, whether stratified by predicted 7-year survival or by PROM. Discriminative performance was comparable between the ASCERT and PROM models for 7-year survival prediction (p validated for prediction of long-term survival after coronary artery bypass grafting in all risk groups. The widely used STS PROM performed comparably as a predictor of long-term survival. Both tools provide important information for preoperative decision making and patient counseling about potential outcomes after coronary artery bypass grafting. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  9. MATHEMATICAL RISK ANALYSIS: VIA NICHOLAS RISK MODEL AND BAYESIAN ANALYSIS

    Directory of Open Access Journals (Sweden)

    Anass BAYAGA

    2010-07-01

    Full Text Available The objective of this second part of a two-phased study was to explorethe predictive power of quantitative risk analysis (QRA method andprocess within Higher Education Institution (HEI. The method and process investigated the use impact analysis via Nicholas risk model and Bayesian analysis, with a sample of hundred (100 risk analysts in a historically black South African University in the greater Eastern Cape Province.The first findings supported and confirmed previous literature (KingIII report, 2009: Nicholas and Steyn, 2008: Stoney, 2007: COSA, 2004 that there was a direct relationship between risk factor, its likelihood and impact, certiris paribus. The second finding in relation to either controlling the likelihood or the impact of occurrence of risk (Nicholas risk model was that to have a brighter risk reward, it was important to control the likelihood ofoccurrence of risks as compared with its impact so to have a direct effect on entire University. On the Bayesian analysis, thus third finding, the impact of risk should be predicted along three aspects. These aspects included the human impact (decisions made, the property impact (students and infrastructural based and the business impact. Lastly, the study revealed that although in most business cases, where as business cycles considerably vary dependingon the industry and or the institution, this study revealed that, most impacts in HEI (University was within the period of one academic.The recommendation was that application of quantitative risk analysisshould be related to current legislative framework that affects HEI.

  10. Country risk analysis

    International Nuclear Information System (INIS)

    David, A.

    1992-01-01

    This paper reports that the oil industry has been an internationally based industry that has been heavily dependent on outside financing sources. Historically, financing came from investment houses that, in most cases, participated in the projects as equity investors. However, investment companies can no longer satisfy the capital requirements of the current high level of exploration and development activities. The current trend is to involve commercial banks on a purely lending basis. Commercial banks, by their nature, are risk averse. In the case of oil and gas exploration and production they are asked to take not only technical risk and price risk but geopolitical risk as well. Methods have been developed by commercial banks to reduce technical and price risks to point which enables them to be comfortable with a loan. However, geopolitical risks are more difficult to assess. The risk associated with many countries are the nationalization of the investment, new tax restrictions, restriction of currency movements, and/or revisions to the production sharing agreements

  11. Hypertension, Obesity, Diabetes, and Heart Failure-Free Survival: The Cardiovascular Disease Lifetime Risk Pooling Project.

    Science.gov (United States)

    Ahmad, Faraz S; Ning, Hongyan; Rich, Jonathan D; Yancy, Clyde W; Lloyd-Jones, Donald M; Wilkins, John T

    2016-12-01

    This study was designed to quantify the relationship between the absence of heart failure risk factors in middle age and incident heart failure, heart failure-free survival, and overall survival. Quantification of years lived free from heart failure in the context of risk factor burden in mid-life may improve risk communication and prevention efforts. We conducted a pooled, individual-level analysis sampling from communities across the United States as part of 4 cohort studies: the Framingham Heart, Framingham Offspring, Chicago Heart Association Detection Project in Industry, and ARIC (Atherosclerosis Risk In Communities) studies. Participants with and without hypertension (blood pressure ≥140/90 mm Hg or treatment), obesity (body mass index ≥30 kg/m 2 ), or diabetes (fasting glucose ≥126 mg/dl or treatment), and combinations of these factors, at index ages of 45 years and 55 years through 95 years. Competing risk-adjusted Cox models, a modified Kaplan-Meier estimator, and Irwin's restricted mean were used to estimate the association between the absence of risk factors at mid-life and incident heart failure, heart failure-free survival, and overall survival. For participants at age 45 years, over 516,537 person-years of follow-up, 1,677 incident heart failure events occurred. Men and women with no risk factors, compared to those with all 3, had 73% to 85% lower risks of incident heart failure. Men and women without hypertension, obesity, or diabetes at age 45 years lived on average 34.7 years and 38.0 years without incident heart failure, and they lived on average an additional 3 years to 15 years longer free of heart failure than those with 1, 2, or 3 risk factors. Similar trends were seen when stratified by race and at index age 55 years. Prevention of hypertension, obesity, and diabetes by ages 45 years and 55 years may substantially prolong heart failure-free survival, decrease heart failure-related morbidity, and reduce the public health impact of

  12. Risk analysis of Odelouca cofferdam

    OpenAIRE

    Pimenta, L.; Caldeira, L.; Maranha das Neves, E.

    2009-01-01

    In this paper we present the risk analysis of Odelouca Cofferdam, using an event tree analysis. The initializing events, failure modes and analysed limit states are discussed based on an influence diagram. The constructed event trees and their interpretation are presented. The obtained risk values are represented in an FN plot superimposed to the acceptability and tolerability risk limits proposed for Portuguese dams. Initially, particular emphasis is placed on the main characteristic...

  13. Risk factors and a prognostic score for survival after autologous stem-cell transplantation for relapsed or refractory Hodgkin lymphoma

    DEFF Research Database (Denmark)

    Bröckelmann, P J; Müller, H; Casasnovas, O

    2017-01-01

    study (n = 1045), precise and valid risk prognostication in HL patients undergoing ASCT can be achieved with five easily available clinical RFs. The proposed prognostic score hence allows reliable stratification of patients for innovative therapeutic approaches in clinical practice and future trials...... therapeutic approaches, we investigated a comprehensive set of risk factors (RFs) for survival after ASCT. Methods: In this multinational prognostic multivariable modeling study, 23 potential RFs were retrospectively evaluated in HL patients from nine prospective trials with multivariable Cox proportional...... of potential RFs had significant impact on progression-free survival (PFS) with hazard ratios (HR) ranging from 1.39 to 2.22. The multivariable analysis identified stage IV disease, time to relapse ≤3 months, ECOG performance status ≥1, bulk ≥5 cm and inadequate response to salvage chemotherapy [

  14. Extinction risk assessment for the species survival plan (SSP) population of the Bali mynah (Leucopsar rothschildi).

    Science.gov (United States)

    Earnhardt, Joanne M; Thompson, Steven D; Faust, Lisa J

    2009-05-01

    The Bali mynah Species Survival Plan (SSP), an Association of Zoos and Aquariums program, strives to maintain the genetic and demographic health of its population, avoid unplanned changes in size, and minimize the risk of population extinction. The SSP population meets current demographic and genetic objectives with a population size of 209 birds at 61 institutions and 96% genetic diversity (GD) retained from the source population. However, participating institutions have expressed concerns regarding space allocation, target population size (TPS), breeding restrictions, inbreeding depression, and harvest in relation to future population availability and viability. Based on these factors, we assess five questions with a quantitative risk assessment, specifically a population viability analysis (PVA) using ZooRisk software. Using an individual-based stochastic model, we project potential population changes under different conditions (e.g. changes in TPS and genetic management) to identify the most effective management actions. Our projections indicate that under current management conditions, population decline and extinction are unlikely and that although GD will decline over 100 years the projected loss does not exceed levels acceptable to population managers (less than 90% GD retained). Model simulations indicate that the combination of two genetic management strategies (i.e. priority breeding based on mean kinship and inbreeding avoidance) benefits the retention of GD and reduces the accumulation of inbreeding. The current TPS (250) is greater than necessary to minimize the risk of extinction for the SSP population but any reduction in TPS must be accompanied by continued application of genetic management. If carefully planned, birds can be harvested for transfer to Bali for a reintroduction program without jeopardizing the SSP population.

  15. Androgen Suppression Combined with Elective Nodal and Dose Escalated Radiation Therapy (the ASCENDE-RT Trial): An Analysis of Survival Endpoints for a Randomized Trial Comparing a Low-Dose-Rate Brachytherapy Boost to a Dose-Escalated External Beam Boost for High- and Intermediate-risk Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Morris, W. James, E-mail: jmorris@bccancer.bc.ca [Department of Surgery, University of British Columbia, Vancouver, British Columbia (Canada); BC Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada); Tyldesley, Scott [Department of Surgery, University of British Columbia, Vancouver, British Columbia (Canada); BC Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada); Rodda, Sree [Department of Surgery, University of British Columbia, Vancouver, British Columbia (Canada); Halperin, Ross [Department of Surgery, University of British Columbia, Vancouver, British Columbia (Canada); BC Cancer Agency–Centre for the Southern Interior, Vancouver, British Columbia (Canada); Pai, Howard [Department of Surgery, University of British Columbia, Vancouver, British Columbia (Canada); BC Cancer Agency–Vancouver Island Centre, Vancouver, British Columbia (Canada); McKenzie, Michael; Duncan, Graeme [Department of Surgery, University of British Columbia, Vancouver, British Columbia (Canada); BC Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada); Morton, Gerard [Department of Radiation Oncology, University of Toronto, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada); Hamm, Jeremy [Department of Population Oncology, BC Cancer Agency, Vancouver, British Columbia (Canada); Murray, Nevin [BC Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada); Department of Medicine, University of British Columbia, Vancouver, British Columbia (Canada)

    2017-06-01

    Purpose: To report the primary endpoint of biochemical progression-free survival (b-PFS) and secondary survival endpoints from ASCENDE-RT, a randomized trial comparing 2 methods of dose escalation for intermediate- and high-risk prostate cancer. Methods and Materials: ASCENDE-RT enrolled 398 men, with a median age of 68 years; 69% (n=276) had high-risk disease. After stratification by risk group, the subjects were randomized to a standard arm with 12 months of androgen deprivation therapy, pelvic irradiation to 46 Gy, followed by a dose-escalated external beam radiation therapy (DE-EBRT) boost to 78 Gy, or an experimental arm that substituted a low-dose-rate prostate brachytherapy (LDR-PB) boost. Of the 398 trial subjects, 200 were assigned to DE-EBRT boost and 198 to LDR-PB boost. The median follow-up was 6.5 years. Results: In an intent-to-treat analysis, men randomized to DE-EBRT were twice as likely to experience biochemical failure (multivariable analysis [MVA] hazard ratio [HR] 2.04; P=.004). The 5-, 7-, and 9-year Kaplan-Meier b-PFS estimates were 89%, 86%, and 83% for the LDR-PB boost versus 84%, 75%, and 62% for the DE-EBRT boost (log-rank P<.001). The LDR-PB boost benefited both intermediate- and high-risk patients. Because the b-PFS curves for the treatment arms diverge sharply after 4 years, the relative advantage of the LDR-PB should increase with longer follow-up. On MVA, the only variables correlated with reduced overall survival were age (MVA HR 1.06/y; P=.004) and biochemical failure (MVA HR 6.30; P<.001). Although biochemical failure was associated with increased mortality and randomization to DE-EBRT doubled the rate of biochemical failure, no significant overall survival difference was observed between the treatment arms (MVA HR 1.13; P=.62). Conclusions: Compared with 78 Gy EBRT, men randomized to the LDR-PB boost were twice as likely to be free of biochemical failure at a median follow-up of 6.5 years.

  16. Does chemotherapy improve survival in high-risk stage I and II Merkel cell carcinoma of the skin?

    International Nuclear Information System (INIS)

    Poulsen, Michael G.; Rischin, Danny; Porter, Ian; Walpole, Euan; Harvey, Jennifer; Hamilton, Chris; Keller, Jacqui; Tripcony, Lee

    2006-01-01

    Purpose: The effectiveness of synchronous carboplatin, etoposide, and radiation therapy in improving survival was evaluated by comparison of a matched set of historic control subjects with patients treated in a prospective Phase II study that used synchronous chemotherapy and radiation and adjuvant chemotherapy. Patients and Methods: Patients were included in the analysis if they had disease localized to the primary site and nodes, and they were required to have at least one of the following high-risk features: recurrence after initial therapy, involved nodes, primary size greater than 1 cm, or gross residual disease after surgery. All patients who received chemotherapy were treated in a standardized fashion as part of a Phase II study (Trans-Tasman Radiation Oncology Group TROG 96:07) from 1997 to 2001. Radiation was delivered to the primary site and nodes to a dose of 50 Gy in 25 fractions over 5 weeks, and synchronous carboplatin (AUC 4.5) and etoposide, 80 mg/m 2 i.v. on Days 1 to 3, were given in Weeks 1, 4, 7, and 10. The historic group represents a single institution's experience from 1988 to 1996 and was treated with surgery and radiation alone, and patients were included if they fulfilled the eligibility criteria of TROG 96:07. Patients with occult cutaneous disease were not included for the purpose of this analysis. Because of imbalances in the prognostic variables between the two treatment groups, comparisons were made by application of Cox's proportional hazard modeling. Overall survival, disease-specific survival, locoregional control, and distant control were used as endpoints for the study. Results: Of the 102 patients who had high-risk Stage I and II disease, 40 were treated with chemotherapy (TROG 96:07) and 62 were treated without chemotherapy (historic control subjects). When Cox's proportional hazards modeling was applied, the only significant factors for overall survival were recurrent disease, age, and the presence of residual disease. For

  17. Estimating Probability of Default on Peer to Peer Market – Survival Analysis Approach

    Directory of Open Access Journals (Sweden)

    Đurović Andrija

    2017-05-01

    Full Text Available Arguably a cornerstone of credit risk modelling is the probability of default. This article aims is to search for the evidence of relationship between loan characteristics and probability of default on peer-to-peer (P2P market. In line with that, two loan characteristics are analysed: 1 loan term length and 2 loan purpose. The analysis is conducted using survival analysis approach within the vintage framework. Firstly, 12 months probability of default through the cycle is used to compare riskiness of analysed loan characteristics. Secondly, log-rank test is employed in order to compare complete survival period of cohorts. Findings of the paper suggest that there is clear evidence of relationship between analysed loan characteristics and probability of default. Longer term loans are more risky than the shorter term ones and the least risky loans are those used for credit card payoff.

  18. Application of survival analysis methodology to the quantitative analysis of LC-MS proteomics data

    KAUST Repository

    Tekwe, C. D.; Carroll, R. J.; Dabney, A. R.

    2012-01-01

    positive, skewed and often left-censored, we propose using survival methodology to carry out differential expression analysis of proteins. Various standard statistical techniques including non-parametric tests such as the Kolmogorov-Smirnov and Wilcoxon

  19. Campylobacter Risk Analysis

    DEFF Research Database (Denmark)

    Nauta, Maarten

    In several countries quantitative microbiological risk assessments (QMRAs) have been performed for Campylobacter in chicken meat. The models constructed for this purpose provide a good example of the development of QMRA in general and illustrate the diversity of available methods. Despite...... the differences between the models, the most prominent conclusions of the QMRAs are similar. These conclusions for example relate to the large risk of highly contaminated meat products and the insignificance of contamination from Campylobacter positive flocks to negative flocks during slaughter and processing...

  20. Risk analysis: opening the process

    International Nuclear Information System (INIS)

    Hubert, Ph.; Mays, C.

    1998-01-01

    This conference on risk analysis took place in Paris, 11-14 october 1999. Over 200 paper where presented in the seven following sessions: perception; environment and health; persuasive risks; objects and products; personal and collective involvement; assessment and valuation; management. A rational approach to risk analysis has been developed in the three last decades. Techniques for risk assessment have been thoroughly enhanced, risk management approaches have been developed, decision making processes have been clarified, the social dimensions of risk perception and management have been investigated. Nevertheless this construction is being challenged by recent events which reveal how deficits in stakeholder involvement, openness and democratic procedures can undermine risk management actions. Indeed, the global process most components of risk analysis may be radically called into question. Food safety has lately been a prominent issue, but now debates appear, or old debates are revisited in the domains of public health, consumer products safety, waste management, environmental risks, nuclear installations, automobile safety and pollution. To meet the growing pressures for efficiency, openness, accountability, and multi-partner communication in risk analysis, institutional changes are underway in many European countries. However, the need for stakeholders to develop better insight into the process may lead to an evolution of all the components of risks analysis, even in its most (technical' steps. For stakeholders of different professional background, political projects, and responsibilities, risk identification procedures must be rendered understandable, quantitative risk assessment must be intelligible and accommodated in action proposals, ranging from countermeasures to educational programs to insurance mechanisms. Management formats must be open to local and political input and other types of operational feedback. (authors)

  1. Survival after stroke. Risk factors and determinants in the Copenhagen Stroke Study

    DEFF Research Database (Denmark)

    Kammersgaard, Lars Peter

    2010-01-01

    stroke unit and recruited from a well-defined area in Copenhagen, Denmark. This thesis focuses on the survival after stroke in relation to several baseline clinical characteristics and risk factors for cardiovascular disease. The thesis comes in three sections with regard to whether factors or clinical...

  2. Venous thromboembolism in ovarian cancer: incidence, risk factors and impact on survival.

    LENUS (Irish Health Repository)

    Abu Saadeh, Feras

    2013-09-01

    Ovarian cancer has a higher incidence of venous thromboembolism (VTE) than other cancers. Clear cell cancers carry the highest risk at 11-27%. The aim of this study was to identify the predisposing factors for VTE in a population of ovarian cancer patients and to determine the influence of VTE on overall survival.

  3. estimated glomerular filtration rate and risk of survival in acute stroke

    African Journals Online (AJOL)

    2014-03-03

    Mar 3, 2014 ... ESTIMATED GLOMERULAR FILTRATION RATE AND RISK OF SURVIVAL IN ACUTE STROKE. E. I. Okaka, MBBS, FWACP, F. A. Imarhiagbe, MBChB, FMCP, F. E. Odiase, MBBS, FMCP, O. C. A. Okoye, MBBS, FWACP,. Department of Medicine, University of Benin Teaching Hospital, Benin City, Nigeria.

  4. Survival outcome of intermediate risk neuroblastoma at Children Cancer Hospital Egypt

    Directory of Open Access Journals (Sweden)

    Hossam Elzomor

    2018-03-01

    Conclusion: A very high rate of survival is currently achievable in patients with intermediate risk neuroblastoma by chemotherapy or chemotherapy and surgery. In addition to response, our plan is to adopt biologically-based treatment to reduce treatment-induced complications among survivors.

  5. [Risk factors for falls and survival after falling in elderly people in a community].

    Science.gov (United States)

    Kato, Ryuichi; Takagi, Chika; Sakurai, Naoko; Hoshi, Tanji

    2012-05-01

    The purpose of this study was to assess the risk factors associated with falls and to examine the effects of falls on survival of elderly people in a community. A questionnaire survey was conducted in 16,462 urban elderly dwellers aged 65 years or more in City A in September 2001. A follow-up survey was carried out in September 2004. We analyzed the data of 8,285 subjects who answered both questionnaires and had not relocated by August 2007. Baseline assessments of health and functioning were carried out in 2001. Falls experienced during the 1-year period before September 2004 were recorded, and the deaths were recorded until August 2007. Statistical analysis was performed using a logistic regression model and Cox's proportional hazards analysis. A total of 6,420 subjects (3,127 men and 3,293 women) who had provided complete answers about their falls were included in the analyses. Of these, 27.8% of women and 16.4% of men had experienced falls, while 6.2% of women and 2.1% of men had experienced falls that caused fractures. We found that the likelihood of fall, with or without fracture development, was greater in women than in men (P falls tended to increase with age in both women and men. Risk factors associated with falls, in addition to age and gender, were pain (odds ratio [OR], 1.75), lack of instrumental activities of daily living (IADL; OR, 1.45), poor self-rated health status (OR, 1.42), and presence of disease (OR, 1.35). Risk factors associated with falls that caused fracture were pain (OR, 1.85) and lack of IADL (OR, 1.61). Cox's proportional hazards analysis showed a significant increase in mortality in both men and women who had experienced falls than in those who had not (hazard ratio [HR], 1.94, 1.43). Aging, pain and disease, lack of IADL, and poor self-rated health status were all significant risk factors for falls in elderly people, and a fall was related to subsequent mortality.

  6. Survival analysis and classification methods for forest fire size.

    Science.gov (United States)

    Tremblay, Pier-Olivier; Duchesne, Thierry; Cumming, Steven G

    2018-01-01

    Factors affecting wildland-fire size distribution include weather, fuels, and fire suppression activities. We present a novel application of survival analysis to quantify the effects of these factors on a sample of sizes of lightning-caused fires from Alberta, Canada. Two events were observed for each fire: the size at initial assessment (by the first fire fighters to arrive at the scene) and the size at "being held" (a state when no further increase in size is expected). We developed a statistical classifier to try to predict cases where there will be a growth in fire size (i.e., the size at "being held" exceeds the size at initial assessment). Logistic regression was preferred over two alternative classifiers, with covariates consistent with similar past analyses. We conducted survival analysis on the group of fires exhibiting a size increase. A screening process selected three covariates: an index of fire weather at the day the fire started, the fuel type burning at initial assessment, and a factor for the type and capabilities of the method of initial attack. The Cox proportional hazards model performed better than three accelerated failure time alternatives. Both fire weather and fuel type were highly significant, with effects consistent with known fire behaviour. The effects of initial attack method were not statistically significant, but did suggest a reverse causality that could arise if fire management agencies were to dispatch resources based on a-priori assessment of fire growth potentials. We discuss how a more sophisticated analysis of larger data sets could produce unbiased estimates of fire suppression effect under such circumstances.

  7. Survival analysis and classification methods for forest fire size

    Science.gov (United States)

    2018-01-01

    Factors affecting wildland-fire size distribution include weather, fuels, and fire suppression activities. We present a novel application of survival analysis to quantify the effects of these factors on a sample of sizes of lightning-caused fires from Alberta, Canada. Two events were observed for each fire: the size at initial assessment (by the first fire fighters to arrive at the scene) and the size at “being held” (a state when no further increase in size is expected). We developed a statistical classifier to try to predict cases where there will be a growth in fire size (i.e., the size at “being held” exceeds the size at initial assessment). Logistic regression was preferred over two alternative classifiers, with covariates consistent with similar past analyses. We conducted survival analysis on the group of fires exhibiting a size increase. A screening process selected three covariates: an index of fire weather at the day the fire started, the fuel type burning at initial assessment, and a factor for the type and capabilities of the method of initial attack. The Cox proportional hazards model performed better than three accelerated failure time alternatives. Both fire weather and fuel type were highly significant, with effects consistent with known fire behaviour. The effects of initial attack method were not statistically significant, but did suggest a reverse causality that could arise if fire management agencies were to dispatch resources based on a-priori assessment of fire growth potentials. We discuss how a more sophisticated analysis of larger data sets could produce unbiased estimates of fire suppression effect under such circumstances. PMID:29320497

  8. Survival after radiotherapy in gastric cancer: Systematic review and meta-analysis

    International Nuclear Information System (INIS)

    Valentini, Vincenzo; Cellini, Francesco; Minsky, Bruce D.; Mattiucci, Gian Carlo; Balducci, Mario; D'Agostino, Giuseppe; D'Angelo, Elisa; Dinapoli, Nicola; Nicolotti, Nicola; Valentini, Chiara; La Torre, Giuseppe

    2009-01-01

    Background and purpose: A systematic review and meta-analysis was performed to assess the impact of radiotherapy on both 3- and 5-year survival in patients with resectable gastric cancer. Methods: Randomized Clinical Trials (RCTs) in which radiotherapy, (preoperative, postoperative and/or intraoperative), was compared with surgery alone or surgery plus chemotherapy in resectable gastric cancer were identified by searching web-based databases and supplemented by manual examination of reference lists. Meta-analysis was performed using Risk Ratios (RRs). Random or fixed effects models were used to combine data. The methodological quality was evaluated by Chalmers' score. Results: Radiotherapy had a significant impact on 5-year survival. Using an intent to treat (ITT) and a Per Protocol (PP) analysis, the overall 5-year RR was 1.26 (95% CI: 1.08-1.48; NNT = 17) and 1.31 (95% CI: 1.04-1.66; NNT = 13), respectively. Although the quality of the studies was variable, the data were consistent and no clear publication bias was found. Conclusion: This meta-analysis showed a statistically significant 5-year survival benefit with the addition of radiotherapy in patients with resectable gastric cancer. Radiotherapy remains a standard component in the treatment of resectable gastric cancer and new RCTs need to address the impact of new conformal radiotherapy technologies.

  9. Advances in probabilistic risk analysis

    International Nuclear Information System (INIS)

    Hardung von Hardung, H.

    1982-01-01

    Probabilistic risk analysis can now look back upon almost a quarter century of intensive development. The early studies, whose methods and results are still referred to occasionally, however, only permitted rough estimates to be made of the probabilities of recognizable accident scenarios, failing to provide a method which could have served as a reference base in calculating the overall risk associated with nuclear power plants. The first truly solid attempt was the Rasmussen Study and, partly based on it, the German Risk Study. In those studies, probabilistic risk analysis has been given a much more precise basis. However, new methodologies have been developed in the meantime, which allow much more informative risk studies to be carried out. They have been found to be valuable tools for management decisions with respect to backfitting, reinforcement and risk limitation. Today they are mainly applied by specialized private consultants and have already found widespread application especially in the USA. (orig.) [de

  10. Long-Term Survival in Young Women: Hazards and Competing Risks after Thyroid Cancer

    International Nuclear Information System (INIS)

    Stroup, A. M.; Harrell, C. J.; Herget, K. A.

    2012-01-01

    Differentiated thyroid cancers (DTCs) are one of the most common and survivable cancers diagnosed in women. We examine factors associated with long-term survival and competing risks of death in women diagnosed with DTC under the age of 40 (<40) and aged 40 and older (40+). Methods. SEER data was used to identify DTCs diagnosed in women from 1975 to 2009. We examined overall (OS), disease-specific (DSS), other cancer (OCS), and non-cancer-related (NCS) survival using multivariate Cox proportional hazards modeling. Results. Observed survival was 97.2% for <40 (n=14,540) and 82.5% for 40+ (n=20,513). Distant stage (HR=1.96, 95% CI 1.23-3.07), non-Hispanic Black (HR=2.04, 95% CI 1.45-2.87), being unmarried (HR=1.26, 95% 1.03-1.54), and subsequent primary cancers (HR=4.63, 95% CI 3.76-5.71) were significant for OS in women <40. Age was an effect modifier for all survival outcomes. Racial disparities in NCS were most pronounced for young non-Hispanic black women (HR=3.36, 95% CI 2.17-5.22). Women in both age groups were more likely to die from other causes. Conclusions. Age at diagnosis remains one of the strongest prognostic factors for thyroid cancer survival. More directed efforts to ensure effective care for co morbid conditions are needed to reduce mortality from other causes.

  11. Multiple imputation for estimating the risk of developing dementia and its impact on survival.

    Science.gov (United States)

    Yu, Binbing; Saczynski, Jane S; Launer, Lenore

    2010-10-01

    Dementia, Alzheimer's disease in particular, is one of the major causes of disability and decreased quality of life among the elderly and a leading obstacle to successful aging. Given the profound impact on public health, much research has focused on the age-specific risk of developing dementia and the impact on survival. Early work has discussed various methods of estimating age-specific incidence of dementia, among which the illness-death model is popular for modeling disease progression. In this article we use multiple imputation to fit multi-state models for survival data with interval censoring and left truncation. This approach allows semi-Markov models in which survival after dementia depends on onset age. Such models can be used to estimate the cumulative risk of developing dementia in the presence of the competing risk of dementia-free death. Simulations are carried out to examine the performance of the proposed method. Data from the Honolulu Asia Aging Study are analyzed to estimate the age-specific and cumulative risks of dementia and to examine the effect of major risk factors on dementia onset and death.

  12. Introduction of the risk analysis

    International Nuclear Information System (INIS)

    Campon, G.; Martinez, I.

    2013-01-01

    An introduction of risks analysis was given in the exposition which main issues were: food innocuousness, world, regional and national food context,change of paradigms, health definition, risk, codex, standardization, food chain role, trade agreement, codex alimentarius, food transmission diseases cost impact

  13. Hydroproject risk analysis

    International Nuclear Information System (INIS)

    Murdock, R.V.; Gulliver, J.S.

    1991-01-01

    Traditionally, economic feasibility studies performed for potential hydropower plant sites have included either no uncertainty or at best an ad hoc value associated with estimated benefits. However, formal methods for analyzing uncertainty do exist and have been outlined in the past. An application of these methods is demonstrated through conversion of a hydropower survey program, HYFEAS, to run on LOTUS 1-2-3, using the add-in software package RISK. In this paper the program principals are outlined and a case study of it's application to a hydropower site is presented

  14. Retrospective Analysis of the Survival Benefit of Induction Chemotherapy in Stage IVa-b Nasopharyngeal Carcinoma.

    Science.gov (United States)

    Lan, Xiao-Wen; Zou, Xue-Bin; Xiao, Yao; Tang, Jie; OuYang, Pu-Yun; Su, Zhen; Xie, Fang-Yun

    2016-01-01

    The value of adding induction chemotherapy to chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma (LA-NPC) remains controversial, yet high-risk patients with LA-NPC have poor outcomes after chemoradiotherapy. We aimed to assess the survival benefits of induction chemotherapy in stage IVa-b NPC. A total of 602 patients with stage IVa-b NPC treated with intensity-modulated radiation therapy (IMRT) and concurrent chemotherapy with or without induction chemotherapy were retrospectively analyzed. Overall survival (OS), locoregional relapse-free survival (LRFS), distant metastasis-free survival (DMFS) and progression-free survival (PFS) were evaluated using the Kaplan-Meier method, log-rank test and Cox regression analysis. In univariate analysis, 5-year OS was 83.2% for induction chemotherapy plus concurrent chemotherapy and 74.8% for concurrent chemotherapy alone, corresponding to an absolute risk reduction of 8.4% (P = 0.022). Compared to concurrent chemotherapy alone, addition of induction chemotherapy improved 5-year DMFS (83.2% vs. 74.4%, P = 0.018) but not 5-year LRFS (83.7% vs. 83.0%, P = 0.848) or PFS (71.9% vs. 66.0%, P = 0.12). Age, T category, N category, chemotherapy strategy and clinical stage were associated with 5-year OS (P = 0.017, P = 0.031, P = 0.007, P = 0.022, P = 0.001, respectively). In multivariate analysis, induction chemotherapy plus concurrent chemotherapy was an independent favorable prognostic factor for OS (HR, 0.62; 95% CI, 0.43-0.90, P = 0.012) and DMFS (HR, 0.57; 95% CI, 0.38-0.83, P = 0.004). In subgroup analysis, induction chemotherapy significantly improved 5-year DMFS in stage IVa (86.8% vs. 77.3%, P = 0.008), but provided no significant benefit in stage IVb. In patients with stage IVa-b NPC treated with IMRT, addition of induction chemotherapy to concurrent chemotherapy significantly improved 5-year OS and 5-year DMFS. This study provides a basis for selection of high risk patients in future clinical therapeutic

  15. Parent-child communication and marijuana initiation: evidence using discrete-time survival analysis.

    Science.gov (United States)

    Nonnemaker, James M; Silber-Ashley, Olivia; Farrelly, Matthew C; Dench, Daniel

    2012-12-01

    This study supplements existing literature on the relationship between parent-child communication and adolescent drug use by exploring whether parental and/or adolescent recall of specific drug-related conversations differentially impact youth's likelihood of initiating marijuana use. Using discrete-time survival analysis, we estimated the hazard of marijuana initiation using a logit model to obtain an estimate of the relative risk of initiation. Our results suggest that parent-child communication about drug use is either not protective (no effect) or - in the case of youth reports of communication - potentially harmful (leading to increased likelihood of marijuana initiation). Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Outcomes and long-term survival of coronary artery surgery: The controversial role of opium as risk marker

    Science.gov (United States)

    Najafi, Mahdi; Jahangiry, Leila; Mortazavi, Seyedeh Hamideh; Jalali, Arash; Karimi, Abbasali; Bozorgi, Ali

    2016-01-01

    AIM To study survival in isolated coronary artery bypass graft (CABG) patients and to evaluate the impact of preoperative chronic opium consumption on long-term outcome. METHODS Cohort of 566 isolated CABG patients as Tehran Heart Center cardiac output measurement was conducted. Daily evaluation until discharge as well as 4- and 12-mo and 6.5-year follow-up information for survival status were fulfilled for all patients. Long-term 6.5-year overall and opium-stratified survival, adjusted survival curves based on opium consumption as well as possible predictors of all-cause mortality using multiple cox regression were determined by statistical analysis. RESULTS Six point five-year overall survival was 91.8%; 86.6% in opium consumers and 92.7% in non-opium consumers (P = 0.035). Patients with positive history of opium consumption significantly tended to have lower ejection fraction (EF), higher creatinine level and higher prevalence of myocardial infarction. Multiple predictors of all-cause mortality included age, body mass index, EF, diabetes mellitus and cerebrovascular accident. The hazard ratio (HR) of 2.09 for the risk of mortality in opium addicted patients with a borderline P value (P = 0.052) was calculated in this model. Further adjustment with stratification based on smoking and opium addiction reduced the HR to 1.20 (P = 0.355). CONCLUSION Simultaneous impact of smoking as a confounding variable in most of the patients prevents from definitive judgment on the role of opium as an independent contributing factor in worse long-term survival of CABG patients in addition to advanced age, low EF, diabetes mellitus and cerebrovascular accident. Meanwhile, our findings do not confirm any cardio protective role for opium to improve outcome in coronary patients with the history of smoking. Further studies are needed to clarify pure effect of opium and warrant the aforementioned findings. PMID:27957254

  17. Nutrition support can bring survival benefit to high nutrition risk gastric cancer patients who received chemotherapy.

    Science.gov (United States)

    Qiu, Miaozhen; Zhou, Yi-xin; Jin, Yin; Wang, Zi-xian; Wei, Xiao-li; Han, Hong-yu; Ye, Wen-feng; Zhou, Zhi-wei; Zhang, Dong-sheng; Wang, Feng-hua; Li, Yu-hong; Yang, Da-jun; Xu, Rui-hua

    2015-07-01

    The aim of our study is firstly to evaluate the prevalence and prognostic value of nutrition risk in gastric cancer patients and secondly to explore whether the nutrition support can prolong the survival of advanced gastric cancer patients. It contained two study periods. In the first period, we prospectively evaluated the nutritional risk of gastric adenocarcinoma patients from 2009 to 2011 using the method of European Nutritional Risk Screening (NRS) 2002. The Kaplan-Meier method and log-rank test were used to evaluate the prognostic value of high nutrition risk. The second period was between 2012 and 2013. We prospectively gave the nutrition support to stage IV gastric cancer patients whose NRS is ≥3. There were 830 patients in the first period, 50.7% patients with a NRS ≥ 3. Patients with NRS ≥ 3 presented a significantly higher percentage of stage IV diseases, elevated values of C-reactive protein, and hypoproteinemia. The median survival was significantly higher in NRS nutrition support. The median survival was 14.3 and 9.6 months for patients with and without NRS shift, respectively, P = 0.001. NRS ≥ 3 was an independent adverse prognostic factor in gastric cancer patients. For stage IV patients whose NRS ≥ 3, the nutrition support might be helpful to improve the prognosis.

  18. An Approach to Addressing Selection Bias in Survival Analysis

    Science.gov (United States)

    Carlin, Caroline S.; Solid, Craig A.

    2014-01-01

    This work proposes a frailty model that accounts for non-random treatment assignment in survival analysis. Using Monte Carlo simulation, we found that estimated treatment parameters from our proposed endogenous selection survival model (esSurv) closely parallel the consistent two-stage residual inclusion (2SRI) results, while offering computational and interpretive advantages. The esSurv method greatly enhances computational speed relative to 2SRI by eliminating the need for bootstrapped standard errors, and generally results in smaller standard errors than those estimated by 2SRI. In addition, esSurv explicitly estimates the correlation of unobservable factors contributing to both treatment assignment and the outcome of interest, providing an interpretive advantage over the residual parameter estimate in the 2SRI method. Comparisons with commonly used propensity score methods and with a model that does not account for non-random treatment assignment show clear bias in these methods that is not mitigated by increased sample size. We illustrate using actual dialysis patient data comparing mortality of patients with mature arteriovenous grafts for venous access to mortality of patients with grafts placed but not yet ready for use at the initiation of dialysis. We find strong evidence of endogeneity (with estimate of correlation in unobserved factors ρ̂ = 0.55), and estimate a mature-graft hazard ratio of 0.197 in our proposed method, with a similar 0.173 hazard ratio using 2SRI. The 0.630 hazard ratio from a frailty model without a correction for the non-random nature of treatment assignment illustrates the importance of accounting for endogeneity. PMID:24845211

  19. Long-Term Survival and Risk of Second Cancers After Radiotherapy for Cervical Cancer

    International Nuclear Information System (INIS)

    Ohno, Tatsuya; Kato, Shingo; Sato, Shinichiro; Fukuhisa, Kenjiro; Nakano, Takashi; Tsujii, Hirohiko; Arai, Tatsuo

    2007-01-01

    Purpose: To evaluate the risk of second cancers after cervical cancer treated with radiotherapy for Asian populations. Methods and Materials: We reviewed 2,167 patients with cervical cancer undergoing radiotherapy between 1961 and 1986. Intracavitary brachytherapy was performed with high-dose rate source (82%) or low-dose rate source (12%). Relative risk (RR), absolute excess risk (AR), and cumulative risk of second cancer were calculated using the Japanese disease expectancy table. For 1,031 patients, the impact of smoking habit on the increasing risk of second cancer was also evaluated. Results: The total number of person-years of follow-up was 25,771, with 60 patients being lost to follow-up. Among the 2,167 patients, 1,063 (49%) survived more than 10 years. Second cancers were observed in 210 patients, representing a significant 1.2-fold risk (95% confidence interval [CI], 1.1-1.4) of developing second cancer compared with the general population, 1.6% excess risk per person per decade of follow-up, and elevating cumulative risk up to 23.8% (95% CI, 20.3-27.3) at 30 years after radiotherapy. The RR of second cancer was 1.6-fold for patients with the smoking habit and 1.4-fold for those without. Conclusions: Small but significant increased risk of second cancer was observed among Japanese women with cervical cancer mainly treated with high-dose rate brachytherapy. Considering the fact that about half of the patients survived more than 10 years, the benefit of radiotherapy outweighs the risk of developing second cancer

  20. Albumin-Bilirubin and Platelet-Albumin-Bilirubin Grades Accurately Predict Overall Survival in High-Risk Patients Undergoing Conventional Transarterial Chemoembolization for Hepatocellular Carcinoma.

    Science.gov (United States)

    Hansmann, Jan; Evers, Maximilian J; Bui, James T; Lokken, R Peter; Lipnik, Andrew J; Gaba, Ron C; Ray, Charles E

    2017-09-01

    To evaluate albumin-bilirubin (ALBI) and platelet-albumin-bilirubin (PALBI) grades in predicting overall survival in high-risk patients undergoing conventional transarterial chemoembolization for hepatocellular carcinoma (HCC). This single-center retrospective study included 180 high-risk patients (142 men, 59 y ± 9) between April 2007 and January 2015. Patients were considered high-risk based on laboratory abnormalities before the procedure (bilirubin > 2.0 mg/dL, albumin 1.2 mg/dL); presence of ascites, encephalopathy, portal vein thrombus, or transjugular intrahepatic portosystemic shunt; or Model for End-Stage Liver Disease score > 15. Serum albumin, bilirubin, and platelet values were used to determine ALBI and PALBI grades. Overall survival was stratified by ALBI and PALBI grades with substratification by Child-Pugh class (CPC) and Barcelona Liver Clinic Cancer (BCLC) stage using Kaplan-Meier analysis. C-index was used to determine discriminatory ability and survival prediction accuracy. Median survival for 79 ALBI grade 2 patients and 101 ALBI grade 3 patients was 20.3 and 10.7 months, respectively (P  .05). ALBI and PALBI grades are accurate survival metrics in high-risk patients undergoing conventional transarterial chemoembolization for HCC. Use of these scores allows for more refined survival stratification within CPC and BCLC stage. Copyright © 2017 SIR. Published by Elsevier Inc. All rights reserved.

  1. STOCHASTIC METHODS IN RISK ANALYSIS

    Directory of Open Access Journals (Sweden)

    Vladimíra OSADSKÁ

    2017-06-01

    Full Text Available In this paper, we review basic stochastic methods which can be used to extend state-of-the-art deterministic analytical methods for risk analysis. We can conclude that the standard deterministic analytical methods highly depend on the practical experience and knowledge of the evaluator and therefore, the stochastic methods should be introduced. The new risk analysis methods should consider the uncertainties in input values. We present how large is the impact on the results of the analysis solving practical example of FMECA with uncertainties modelled using Monte Carlo sampling.

  2. Gastric dilation-volvulus in dogs attending UK emergency-care veterinary practices: prevalence, risk factors and survival.

    Science.gov (United States)

    O'Neill, D G; Case, J; Boag, A K; Church, D B; McGreevy, P D; Thomson, P C; Brodbelt, D C

    2017-11-01

    To report prevalence, risk factors and clinical outcomes for presumptive gastric dilation-volvulus diagnosed among an emergency-care population of UK dogs. The study used a cross-sectional design using emergency-care veterinary clinical records from the VetCompass Programme spanning September 1, 2012 to February 28, 2014 and risk factor analysis using multivariable logistic regression modelling. The study population comprised 77,088 dogs attending 50 Vets Now clinics. Overall, 492 dogs had presumptive gastric dilation-volvulus diagnoses, giving a prevalence of 0·64% (95% Confidence interval: 0·58 to 0·70%). Compared with cross-bred dogs, breeds with the highest odds ratios for the diagnosis of presumptive gastric dilation-volvulus were the great Dane (odds ratio: 114·3, 95% Confidence interval 55·1 to 237·1, Pdogs aged up to 12 years and neutered male dogs had 1·3 (95% Confidence interval 1·0 to 1·8, P=0·041) times the odds compared with entire females. Of the cases that were presented alive, 49·7% survived to discharge overall, but 79·3% of surgical cases survived to discharge. Approximately 80% of surgically managed cases survived to discharge. Certain large breeds were highly predisposed. © 2017 British Small Animal Veterinary Association.

  3. Cancer risk and survival in path_MMR carriers by gene and gender up to 75 years of age

    DEFF Research Database (Denmark)

    Møller, Pål; Seppälä, Toni; Bernstein, Inge

    2017-01-01

    BACKGROUND: Most patients with path_MMR gene variants (Lynch syndrome (LS)) now survive both their first and subsequent cancers, resulting in a growing number of older patients with LS for whom limited information exists with respect to cancer risk and survival. OBJECTIVE AND DESIGN......%, duodenum 67%, stomach 61%, bile duct 29%, brain 22% and pancreas 0%. Path_PMS2 carriers had lower risk for cancer. CONCLUSION: Carriers of different path_MMR variants exhibit distinct patterns of cancer risk and survival as they age. Risk estimates for counselling and planning of surveillance and treatment...

  4. Plasma Riboflavin Level is Associated with Risk, Relapse, and Survival of Esophageal Squamous Cell Carcinoma.

    Science.gov (United States)

    Li, Shan-Shan; Xu, Yi-Wei; Wu, Jian-Yi; Tan, Hua-Zhen; Wu, Zhi-Yong; Xue, Yu-Jie; Zhang, Jian-Jun; Li, En-Min; Xu, Li-Yan

    2017-01-01

    Riboflavin is an essential micronutrient for normal cellular activity, and deficiency may result in disease, such as cancer. We performed a case-control study to explore the association of riboflavin levels with risk and prognosis of esophageal squamous cell carcinoma (ESCC). Plasma riboflavin levels, as measured by enzyme-linked immunosorbent assay (ELISA), in ESCC patients were significantly lower than in those of healthy controls (7.04 ± 6.34 ng/ml vs. 9.32 ± 12.40 ng/ml; P riboflavin level and risk of ESCC (odds ratio (OR) = 0.97, 95% confidence interval (CI) = 0.95-0.99, P =  0.02). The 5-year relapse-free and overall survival rates were significantly lower when riboflavin levels were ≤0.8 ng/ml than >0.8 ng/ml (relapse-free survival rate: 29.4% vs. 54.8%; overall survival rate: 28.6% vs. 55.6%). Plasma riboflavin level was an independent protective factor for both relapse-free (hazard ratio (HR) = 0.325, 95% CI = 0.161-0.657, P = 0.002) and overall survival of ESCC patients (HR = 0.382, 95% CI = 0.190-0.768, P = 0.007). In conclusion, plasma riboflavin levels are significantly related to risk and prognosis of ESCC patients, suggesting that moderate supplementation of riboflavin will decrease risk and prevent recurrence of ESCC and also improve prognosis of ESCC patients.

  5. Multiple Imputation for Estimating the Risk of Developing Dementia and Its Impact on Survival

    OpenAIRE

    Yu, Binbing; Saczynski, Jane S.; Launer, Lenore J.

    2010-01-01

    Dementia, Alzheimer’s disease in particular, is one of the major causes of disability and decreased quality of life among the elderly and a leading obstacle to successful aging. Given the profound impact on public health, much research has focused on the age-specific risk of developing dementia and the impact on survival. Early work has discussed various methods of estimating age-specific incidence of dementia, among which the illness-death model is popular for modeling disease progression. I...

  6. Colorectal cancer risk and patients' survival: influence of polymorphisms in genes somatically mutated in colorectal tumors

    Czech Academy of Sciences Publication Activity Database

    Huhn, S.; Bevier, M.; Pardini, Barbara; Naccarati, Alessio; Vodičková, Ludmila; Novotný, J.; Vodička, Pavel; Hemminki, K.; Försti, A.

    2014-01-01

    Roč. 25, č. 6 (2014), s. 759-769 ISSN 0957-5243 R&D Projects: GA ČR(CZ) GAP304/12/1585; GA ČR GAP304/10/1286 Grant - others:GA MŠk(CZ) Prvouk-P27/LF1/1 Institutional support: RVO:68378041 Keywords : colorectal cancer * risk * survival Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.735, year: 2014

  7. Thrombotic Thrombocytopenic Purpura in Black People: Impact of Ethnicity on Survival and Genetic Risk Factors.

    Directory of Open Access Journals (Sweden)

    Suella Martino

    Full Text Available Black people are at increased risk of thrombotic thrombocytopenic purpura (TTP. Whether clinical presentation of TTP in Black patients has specific features is unknown. We assessed here differences in TTP presentation and outcome between Black and White patients. Clinical presentation was comparable between both ethnic groups. However, prognosis differed with a lower death rate in Black patients than in White patients (2.7% versus 11.6%, respectively, P = .04. Ethnicity, increasing age and neurologic involvement were retained as risk factors for death in a multivariable model (P < .05 all. Sixty-day overall survival estimated by the Kaplan-Meier curves and compared with the Log-Rank test confirmed that Black patients had a better survival than White patients (P = .03. Salvage therapies were similarly performed between both groups, suggesting that disease severity was comparable. The comparison of HLA-DRB1*11, -DRB1*04 and -DQB1*03 allele frequencies between Black patients and healthy Black individuals revealed no significant difference. However, the protective allele against TTP, HLA-DRB1*04, was dramatically decreased in Black individuals in comparison with White individuals. Black people with TTP may have a better survival than White patients despite a comparable disease severity. A low natural frequency of HLA-DRB1*04 in Black ethnicity may account for the greater risk of TTP in this population.

  8. Epidemiology of systemic sclerosis: incidence, prevalence, survival, risk factors, malignancy, and environmental triggers.

    Science.gov (United States)

    Barnes, Jammie; Mayes, Maureen D

    2012-03-01

    To identify the recent data regarding prevalence, incidence, survival, and risk factors for systemic sclerosis (SSc) and to compare these data to previously published findings. SSc disease occurrence data are now available for Argentina, Taiwan, and India and continue to show wide variation across geographic regions. The survival rate is negatively impacted by older age of onset, male sex, scleroderma renal crisis, pulmonary fibrosis, pulmonary arterial hypertension, cancer, and antitopoisomerase and anti-U1 antibodies. It appears that silica exposure confers an increased risk for developing scleroderma, but this exposure accounts for a very small proportion of male patients. Smoking is not associated with increased SSc susceptibility. Malignancies are reported in scleroderma at an increased rate, but the magnitude of this risk and the type of cancer vary among reports. Prevalence and incidence of SSc appears to be greater in populations of European ancestry and lower in Asian groups. Exposure to silica dust appears to be an environmental trigger, but this only accounts for a small proportion of male cases. Evidence for increased risk of neoplasia is suggestive, but the magnitude of the risk and the types of malignancies vary among reports.

  9. Exposure, hazard, and survival analysis of diffusion on social networks.

    Science.gov (United States)

    Wu, Jiacheng; Crawford, Forrest W; Kim, David A; Stafford, Derek; Christakis, Nicholas A

    2018-04-29

    Sociologists, economists, epidemiologists, and others recognize the importance of social networks in the diffusion of ideas and behaviors through human societies. To measure the flow of information on real-world networks, researchers often conduct comprehensive sociometric mapping of social links between individuals and then follow the spread of an "innovation" from reports of adoption or change in behavior over time. The innovation is introduced to a small number of individuals who may also be encouraged to spread it to their network contacts. In conjunction with the known social network, the pattern of adoptions gives researchers insight into the spread of the innovation in the population and factors associated with successful diffusion. Researchers have used widely varying statistical tools to estimate these quantities, and there is disagreement about how to analyze diffusion on fully observed networks. Here, we describe a framework for measuring features of diffusion processes on social networks using the epidemiological concepts of exposure and competing risks. Given a realization of a diffusion process on a fully observed network, we show that classical survival regression models can be adapted to estimate the rate of diffusion, and actor/edge attributes associated with successful transmission or adoption, while accounting for the topology of the social network. We illustrate these tools by applying them to a randomized network intervention trial conducted in Honduras to estimate the rate of adoption of 2 health-related interventions-multivitamins and chlorine bleach for water purification-and determine factors associated with successful social transmission. Copyright © 2018 John Wiley & Sons, Ltd.

  10. Probability problems in seismic risk analysis and load combinations for nuclear power plants

    International Nuclear Information System (INIS)

    George, L.L.

    1983-01-01

    This workshop describes some probability problems in power plant reliability and maintenance analysis. The problems are seismic risk analysis, loss of load probability, load combinations, and load sharing. The seismic risk problem is to compute power plant reliability given an earthquake and the resulting risk. Component survival occurs if its peak random response to the earthquake does not exceed its strength. Power plant survival is a complicated Boolean function of component failures and survivals. The responses and strengths of components are dependent random processes, and the peak responses are maxima of random processes. The resulting risk is the expected cost of power plant failure

  11. Improved Survival Endpoints With Adjuvant Radiation Treatment in Patients With High-Risk Early-Stage Endometrial Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Elshaikh, Mohamed A., E-mail: melshai1@hfhs.org [Department of Radiation Oncology, Henry Ford Hospital, Detroit, Michigan (United States); Vance, Sean; Suri, Jaipreet S. [Department of Radiation Oncology, Henry Ford Hospital, Detroit, Michigan (United States); Mahan, Meredith [Public Health Science, Henry Ford Hospital, Detroit, Michigan (United States); Munkarah, Adnan [Division of Gynecologic Oncology, Department of Women' s Health Services, Henry Ford Hospital, Detroit, Michigan (United States)

    2014-02-01

    Purpose/Objective(s): To determine the impact of adjuvant radiation treatment (RT) on recurrence-free survival (RFS), disease-specific survival (DSS), and overall survival (OS) in patients with high-risk 2009 International Federation of Gynecology and Obstetrics stage I-II endometrial carcinoma. Methods and Materials: We identified 382 patients with high-risk EC who underwent hysterectomy. RFS, DSS, and OS were calculated from the date of hysterectomy by use of the Kaplan-Meier method. Cox regression modeling was used to explore the risks associated with various factors on survival endpoints. Results: The median follow-up time for the study cohort was 5.4 years. The median age was 71 years. All patients underwent hysterectomy and salpingo-oophorectomy, 93% had peritoneal cytology, and 85% underwent lymphadenectomy. Patients with endometrioid histology constituted 72% of the study cohort, serous in 16%, clear cell in 7%, and mixed histology in 4%. Twenty-three percent of patients had stage II disease. Adjuvant management included RT alone in 220 patients (57%), chemotherapy alone in 25 patients (7%), and chemoradiation therapy in 27 patients (7%); 110 patients (29%) were treated with close surveillance. The 5-year RFS, DSS, and OS were 76%, 88%, and 73%, respectively. On multivariate analysis, adjuvant RT was a significant predictor of RFS (P<.001) DSS (P<.001), and OS (P=.017). Lymphovascular space involvement was a significant predictor of RFS and DSS (P<.001). High tumor grade was a significant predictor for RFS (P=.038) and DSS (P=.025). Involvement of the lower uterine segment was also a predictor of RFS (P=.049). Age at diagnosis and lymphovascular space involvement were significant predictors of OS: P<.001 and P=.002, respectively. Conclusion: In the treatment of patients with high-risk features, our study suggests that adjuvant RT significantly improves recurrence-free, disease-specific, and overall survival in patients with early-stage endometrial carcinoma

  12. Living donor risk model for predicting kidney allograft and patient survival in an emerging economy.

    Science.gov (United States)

    Zafar, Mirza Naqi; Wong, Germaine; Aziz, Tahir; Abbas, Khawar; Adibul Hasan Rizvi, S

    2018-03-01

    Living donor kidney is the main source of donor organs in low to middle income countries. We aimed to develop a living donor risk model that predicts graft and patient survival in an emerging economy. We used data from the Sindh Institute of Urology and Transplantation (SIUT) database (n = 2283 recipients and n = 2283 living kidney donors, transplanted between 1993 and 2009) and conducted Cox proportional hazard analyses to develop a composite score that predicts graft and patient survivals. Donor factors age, creatinine clearance, nephron dose (estimated by donor/recipient body weight ratio) and human leukocyte antigen (HLA) match were included in the living donor risk model. The adjusted hazard ratios (HRs) for graft failures among those who received a kidney with living donor scores (reference to donor score of zero) of 1, 2, 3 and 4 were 1.14 (95%CI: 0.94-1.39), 1.24 (95%CI:1.03-1.49), 1.25 (95%CI:1.03-1.51) and 1.36 (95%CI:1.08-1.72) (P-value for trend =0.05). Similar findings were observed for patient survival. Similar to findings in high income countries, our study suggests that donor characteristics such as age, nephron dose, creatinine clearance and HLA match are important factors that determine the long-term patient and graft survival in low income countries. However, other crucial but undefined factors may play a role in determining the overall risk of graft failure and mortality in living kidney donor transplant recipients. © 2016 Asian Pacific Society of Nephrology.

  13. ProRisk : risk analysis instrument : developed for William properties

    NARCIS (Netherlands)

    van Doorn, W.H.W.; Egeberg, Ingrid; Hendrickx, Kristoff; Kahramaner, Y.; Masseur, B.; Waijers, Koen; Weglicka, K.A.

    2005-01-01

    This report presents a Risk Analysis Instrument developed for William Properties. Based on the analysis, it appears that the practice of Risk Analysis exists within the organization, yet rather implicit. The Risk Analysis Instrument comes with a package of four components: an activity diagram, a

  14. Common approach of risks analysis

    International Nuclear Information System (INIS)

    Noviello, L.; Naviglio, A.

    1996-01-01

    Although, following the resolutions of the High German Court, the protection level of the human beings is an objective which can change in time, it is obvious that it is an important point when there is a risk for the population. This is true more particularly for the industrial plants whose possible accidents could affect the population. The accidents risk analysis indicates that there is no conceptual difference between the risks of a nuclear power plant and those of the other industrial plants as chemical plants, the gas distribution system and the hydraulic dams. A legislation analysis induced by the Seveso Directive for the industrial risks give some important indications which should always be followed. This work analyses more particularly the legislative situation in different European countries and identifies some of the most important characteristics. Indeed, for most of the countries, the situation is different and it is a later difficulties source for nuclear power plants. In order to strengthen this reasoning, this paper presents some preliminary results of an analysis of a nuclear power plant following the approach of other industrial plants. In conclusion, it will be necessary to analyse again the risks assessment approach for nuclear power plants because the real protection level of human beings in a country is determined by the less regulated of the dangerous industrial plants existing at the surroundings. (O.M.)

  15. Risk Characterization uncertainties associated description, sensitivity analysis

    International Nuclear Information System (INIS)

    Carrillo, M.; Tovar, M.; Alvarez, J.; Arraez, M.; Hordziejewicz, I.; Loreto, I.

    2013-01-01

    The power point presentation is about risks to the estimated levels of exposure, uncertainty and variability in the analysis, sensitivity analysis, risks from exposure to multiple substances, formulation of guidelines for carcinogenic and genotoxic compounds and risk subpopulations

  16. Risk Factors for Survival in a University Hospital Population of Dogs with Epilepsy

    DEFF Research Database (Denmark)

    Fredso, N.; Koch, B. C.; Toft, Nils

    2014-01-01

    BackgroundAlthough a common neurological disorder in dogs, long-term outcome of epilepsy is sparsely documented. ObjectivesTo investigate risk factors for survival and duration of survival in a population of dogs with idiopathic epilepsy or epilepsy associated with a known intracranial cause....... AnimalsOne hundred and two client owned dogs; 78 dogs with idiopathic epilepsy and 24 dogs with epilepsy associated with a known intracranial cause. MethodsA retrospective hospital based study with follow-up. Dogs diagnosed with epilepsy between 2002 and 2008 were enrolled in the study. Owners were...... interviewed by telephone using a structured questionnaire addressing epilepsy status, treatment, death/alive, and cause of death. ResultsMedian life span was 7.6years, 9.2years, and 5.8years for all dogs, and dogs with idiopathic epilepsy or dogs with epilepsy associated with a known intracranial cause (P...

  17. Predicting and Modelling of Survival Data when Cox's Regression Model does not hold

    DEFF Research Database (Denmark)

    Scheike, Thomas H.; Zhang, Mei-Jie

    2002-01-01

    Aalen model; additive risk model; counting processes; competing risk; Cox regression; flexible modeling; goodness of fit; prediction of survival; survival analysis; time-varying effects......Aalen model; additive risk model; counting processes; competing risk; Cox regression; flexible modeling; goodness of fit; prediction of survival; survival analysis; time-varying effects...

  18. Survival outcome of intermediate risk neuroblastoma at Children Cancer Hospital Egypt.

    Science.gov (United States)

    Elzomor, Hossam; Ahmed, Gehad; Elmenawi, Salma; Elkinaai, Naglaa; Refaat, Amal; Soliman, Sonya; Abdelwahab, Mai Amr; Zaghloul, Mohamed Saad; Fawzy, Mohamed

    2018-03-01

    The study aims to evaluate survival outcome in newly diagnosed pediatric intermediate risk neuroblastoma patients treated at the Children Cancer Hospital - Egypt and their relation to various clinical and pathological factors. The study included stage 3 patients INSS) stage 4 disease, stage 4 children 1-1.5 years with favorable biology, and infants stage 4 s (with unfavorable biologic features). Patients received systemic chemotherapy, in the form of etoposide and carboplatin alternating with cyclophosphamide, doxorubicin and vincristine, administered at 3-week intervals, with a total of 6 or 8 cycles guided by reaching objective overall response (complete/very good partial/partial response). The study included 136 patients, 67 males and 69 females. 101 patients had abdominal primary tumors, 28 had mediastinal masss and 7 with masses in the neck; 68% were stage 3 and the remaining (n = 44) had metastatic disease. The three-year overall survival (OS) and event-free survival (EFS) estimates were 94% ± 2% and 90.9% ± 2.5%, respectively. OS and EFS by gender, age, pathology and INPC were all statistically not significantly different. Moreover, OS for patients having surgery versus no surgery (inoperable residual only) was statistically significant (98.4% ± 1.6% & 88.7% ± 5.3%, respectively, p = .034). A very high rate of survival is currently achievable in patients with intermediate risk neuroblastoma by chemotherapy or chemotherapy and surgery. In addition to response, our plan is to adopt biologically-based treatment to reduce treatment-induced complications among survivors. Copyright © 2018 National Cancer Institute, Cairo University. Production and hosting by Elsevier B.V. All rights reserved.

  19. Gallbladder cancer: incidence and survival in a high-risk area of Chile.

    Science.gov (United States)

    Bertran, Enriqueta; Heise, Katy; Andia, Marcelo E; Ferreccio, Catterina

    2010-11-15

    We assessed population incidence rates 1998-2002 and 5-year survival rates of 317 primary gallbladder cancer (GBC) entered in the population-based cancer registry in Valdivia. We analyzed GBC incidence (Poisson regression) and GBC survival (Cox regression). Cases were identified by histology (69.4%), clinical work-up (21.8%), or death certificate only (8.8%). Main symptoms were abdominal pain (82.8%), jaundice (53.6%) nausea (42.6%), and weight loss (38.2%); at diagnosis, 64% had Stage TNM IV. In the period, 4% of histopathological studies from presumptively benign cholecystectomies presented GBC. GBC cases were mainly females (76.0%), urban residents (70.3%), Hispanic (83.7%) of low schooling Mapuche 25.0, Hispanic 16.2 (p = 0.09). The highest SIRs were in Mapuche (269.2) and Hispanic women (199.6) with 8 years of schooling. Low schooling, female and urban residence were independent risk factors. By December 31, 2007, 6 (1.9%) cases were living, 280 (88.3%) died from GBC, 32 (10.1%) were lost of follow-up. Kaplan Meier Global 5-year survival was: 10.3%, 85% at stage I and 1.9% at stage IV; median survival: 3.4 months. Independent poor prognostic factors were TNM IV, jaundice and nonincidental diagnoses. Our results suggest that women of Mapuche ancestry with low schooling (>50 years) are at the highest risk of presenting and dying from GBC and should be the target for early detection programs.

  20. Epidemiology of stroke in the elderly in the Nordic countries. Incidence, survival, prevalence and risk factors

    Directory of Open Access Journals (Sweden)

    Torgeir Engstad

    2012-11-01

    Full Text Available Objective: To review what is known at present with respect to incidence, survival, risk factors and prevalence among the elderly stroke patients in the Nordic countries.Method: This article is based mainly on literature identified through search engines (Mc Master Plus, Cochrane Library, Medline and PubMed, restricted to first-ever stroke in Nordic population-based studies and having applied to the standard WHO definition, a prospective study design and no upper age limit.Results: Data from the Nordic countries show an incidence rate of 1250 to 1796/100 000 in the age group 75-84, and 1628 to 2234 in those above 85 years. The incidence rates are higher among men, but women are expected to contribute more to incident cases due to their higher life expectancy. If the age-specific incidence of stroke remains stable, the proportion of stroke patients aged 80 years and older may reach 50% in a few decades. The elderly stroke patients have a higher 30-days case fatality, and a higher risk of dependency. Better treatment of stroke patients has improved the survival over the last two decades. The prevalence is expected to increase due to the decrease in lethality, a slower fall in incidence and a higher proportion of elderly. Cardiovascular risk factors increase with age. Hypertension is a major risk factor for stroke mortality in the elderly. Cardioembolic stroke due to atrial fibrillation is the most common stroke subtype in the elderly. Lifestyle risk factors are less prevalent in the older stroke patients.Conclusion: The growing proportion of elderly stroke patients is a major challenge for future stroke care. The elderly stroke patients have a different risk factor profile compared to younger stroke patients. Treatment should focus on regaining independency. The age-specific epidemiology of stroke needs to be studied further in large studies in order to plan for future health care.

  1. Long-term survival in pre-specified groups at risk in the Oslo Study, 1972-1973.

    Science.gov (United States)

    Holme, Ingar

    2015-03-01

    Using the Oslo Study of 1972-1973, we wished to compare the long-term mortality pattern up to 40 years, in both the healthy cardiovascular groups at supposedly high and low risk, and in some groups having cardiovascular disease at screening. At the screening, 16,203 (63% of those invited) men aged 40-49 years participated. Study groups were identified by means of questionnaires regarding diseases, blood pressure and measurements of total cholesterol, triglycerides and glucose. We identified six groups: very high cholesterol, very high blood pressure, very high glucose, non-smoking with non-elevated such risk factors, from a randomized diet and antismoking trial, and a randomized drug treatment in mild-to-moderate hypertension. Statistical analyses were by Cox regression analysis, with Kaplan-Meier graphs. The supposedly low-risk group had a total mortality of one-third of other groups, such as: men with hypertension, diabetes or hypercholesterolemia, or those whom participated in the two trials. Between these latter groups, we found 2-5 years of difference in their median survival time, but their absolute risk stayed at rather high levels through all the years, with the median remaining a lifetime that was 3-8 years shorter than the men whom were free of known cardiovascular disease, diabetes or hypertension. The long-term preventive effects on total mortality seem large, if the levels of the classical risk factors of blood pressure, total cholesterol and glucose can be adequately controlled, concurrently with a non-smoking behavior. The study indicated that non-smoking and a low total cholesterol value were the most important contributors to extended survival. © 2015 the Nordic Societies of Public Health.

  2. Causal Mediation Analysis of Survival Outcome with Multiple Mediators.

    Science.gov (United States)

    Huang, Yen-Tsung; Yang, Hwai-I

    2017-05-01

    Mediation analyses have been a popular approach to investigate the effect of an exposure on an outcome through a mediator. Mediation models with multiple mediators have been proposed for continuous and dichotomous outcomes. However, development of multimediator models for survival outcomes is still limited. We present methods for multimediator analyses using three survival models: Aalen additive hazard models, Cox proportional hazard models, and semiparametric probit models. Effects through mediators can be characterized by path-specific effects, for which definitions and identifiability assumptions are provided. We derive closed-form expressions for path-specific effects for the three models, which are intuitively interpreted using a causal diagram. Mediation analyses using Cox models under the rare-outcome assumption and Aalen additive hazard models consider effects on log hazard ratio and hazard difference, respectively; analyses using semiparametric probit models consider effects on difference in transformed survival time and survival probability. The three models were applied to a hepatitis study where we investigated effects of hepatitis C on liver cancer incidence mediated through baseline and/or follow-up hepatitis B viral load. The three methods show consistent results on respective effect scales, which suggest an adverse estimated effect of hepatitis C on liver cancer not mediated through hepatitis B, and a protective estimated effect mediated through the baseline (and possibly follow-up) of hepatitis B viral load. Causal mediation analyses of survival outcome with multiple mediators are developed for additive hazard and proportional hazard and probit models with utility demonstrated in a hepatitis study.

  3. Environmental modeling and health risk analysis (ACTS/RISK)

    National Research Council Canada - National Science Library

    Aral, M. M

    2010-01-01

    ... presents a review of the topics of exposure and health risk analysis. The Analytical Contaminant Transport Analysis System (ACTS) and Health RISK Analysis (RISK) software tools are an integral part of the book and provide computational platforms for all the models discussed herein. The most recent versions of these two softwa...

  4. The survival analysis on localized prostate cancer treated with neoadjuvant endocrine therapy followed by intensity modulated radiation therapy

    International Nuclear Information System (INIS)

    Gao Hong; Li Gaofeng; Wu Qinhong; Li Xuenan; Zhong Qiuzi; Xu Yonggang

    2010-01-01

    Objective: To retrospectively investigate clinical outcomes and prognostic factors in localized prostate cancer treated with neoadjuvant endocrine therapy followed by intensity modulated radiotherapy (IMRT). Methods: Between March 2003 and October 2008, 54 localized prostate cancer treated by IMRT were recruited. All patients had received endocrine therapy before IMRT. The endocrine therapy included surgical castration or medical castration in combination with antiandrogens. The target of IMRT was the prostate and seminal vesicles with or without pelvis. The biochemical failure was defined according to the phoenix definition. By using the risk grouping standard proposed by D'Amico, patients were divided into three groups: low-risk group (n = 5), intermediate-risk group (n = 12), and high-risk group (n = 37). Kaplan-Meier method was used to calculate the overall survival rate. Prognostic factors were analyzed by univariate and multiple Cox regression analysis. Results: The follow-up rate was 98%. The number of patients under follow-up was 39 at 3 years and 25 at 5 years. Potential prognostic factors, including risk groups, mode of endocrine therapy, time of endocrine therapy, phoenix grouping before IMRT, the prostate specific antigen doubling time (PSADT) before radiotherapy, PSA value before IMRT, interval of endocrine therapy and IMRT, irradiation region, and irradiation dose were analyzed by survival analysis. In univariate analysis, time of endocrine therapy (75 % vs 95 %, χ 2 = 6. 45, P = 0. 011), phoenix grouping before IMRT (87% vs 96%, χ 2 = 4. 36, P = 0. 037), interval of endocrine therapy and IMRT (80% vs 95%, χ 2 = 11.60, P= 0. 001), irradiation dose (75% vs 91%, χ 2 =5.92, P= 0. 015) were statistically significant prognostic factors for 3 - year overall survival , and risk groups (85 vs 53 vs 29, χ 2 = 6. 40, P =0. 041) and PSADT before IMRT (62 vs 120, U =24. 50, P =0. 003) were significant factors for the median survival time. In the multiple Cox

  5. Thrombotic Thrombocytopenic Purpura in Black People: Impact of Ethnicity on Survival and Genetic Risk Factors.

    Science.gov (United States)

    Martino, Suella; Jamme, Mathieu; Deligny, Christophe; Busson, Marc; Loiseau, Pascale; Azoulay, Elie; Galicier, Lionel; Pène, Frédéric; Provôt, François; Dossier, Antoine; Saheb, Samir; Veyradier, Agnès; Coppo, Paul

    2016-01-01

    Black people are at increased risk of thrombotic thrombocytopenic purpura (TTP). Whether clinical presentation of TTP in Black patients has specific features is unknown. We assessed here differences in TTP presentation and outcome between Black and White patients. Clinical presentation was comparable between both ethnic groups. However, prognosis differed with a lower death rate in Black patients than in White patients (2.7% versus 11.6%, respectively, P = .04). Ethnicity, increasing age and neurologic involvement were retained as risk factors for death in a multivariable model (P Black patients had a better survival than White patients (P = .03). Salvage therapies were similarly performed between both groups, suggesting that disease severity was comparable. The comparison of HLA-DRB1*11, -DRB1*04 and -DQB1*03 allele frequencies between Black patients and healthy Black individuals revealed no significant difference. However, the protective allele against TTP, HLA-DRB1*04, was dramatically decreased in Black individuals in comparison with White individuals. Black people with TTP may have a better survival than White patients despite a comparable disease severity. A low natural frequency of HLA-DRB1*04 in Black ethnicity may account for the greater risk of TTP in this population.

  6. Association of body mass index and survival in pediatric leukemia: a meta-analysis.

    Science.gov (United States)

    Orgel, Etan; Genkinger, Jeanine M; Aggarwal, Divya; Sung, Lillian; Nieder, Michael; Ladas, Elena J

    2016-03-01

    Obesity is a worldwide epidemic in children and adolescents. Adult cohort studies have reported an association between higher body mass index (BMI) and increased leukemia-related mortality; whether a similar effect exists in childhood leukemia remains controversial. We conducted a meta-analysis to determine whether a higher BMI at diagnosis of pediatric acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML) is associated with worse event-free survival (EFS), overall survival (OS), and cumulative incidence of relapse (CIR). We searched 4 electronic databases from inception through March 2015 without language restriction and included studies in pediatric ALL or AML (0-21 y of age) reporting BMI as a predictor of survival or relapse. Higher BMI, defined as obese (≥95%) or overweight/obese (≥85%), was compared with lower BMI [nonoverweight/obese (children with a higher BMI (RR: 1.35; 95% CI: 1.20, 1.51) than in those at a lower BMI. A higher BMI was associated with significantly increased mortality (RR: 1.31; 95% CI: 1.09, 1.58) and a statistically nonsignificant trend toward greater risk of relapse (RR: 1.17; 95% CI: 0.99, 1.38) compared with a lower BMI. In AML, a higher BMI was significantly associated with poorer EFS and OS (RR: 1.36; 95% CI: 1.16, 1.60 and RR: 1.56; 95% CI: 1.32, 1.86, respectively) than was a lower BMI. Higher BMI at diagnosis is associated with poorer survival in children with pediatric ALL or AML. © 2016 American Society for Nutrition.

  7. Inherited Inflammatory Response Genes Are Associated with B-Cell Non-Hodgkin's Lymphoma Risk and Survival.

    Directory of Open Access Journals (Sweden)

    Kaspar René Nielsen

    Full Text Available Malignant B-cell clones are affected by both acquired genetic alterations and by inherited genetic variations changing the inflammatory tumour microenvironment.We investigated 50 inflammatory response gene polymorphisms in 355 B-cell non-Hodgkin's lymphoma (B-NHL samples encompassing 216 diffuse large B cell lymphoma (DLBCL and 139 follicular lymphoma (FL and 307 controls. The effect of single genes and haplotypes were investigated and gene-expression analysis was applied for selected genes. Since interaction between risk genes can have a large impact on phenotype, two-way gene-gene interaction analysis was included.We found inherited SNPs in genes critical for inflammatory pathways; TLR9, IL4, TAP2, IL2RA, FCGR2A, TNFA, IL10RB, GALNT12, IL12A and IL1B were significantly associated with disease risk and SELE, IL1RN, TNFA, TAP2, MBL2, IL5, CX3CR1, CHI3L1 and IL12A were, associated with overall survival (OS in specific diagnostic entities of B-NHL. We discovered noteworthy interactions between DLBCL risk alleles on IL10 and IL4RA and FL risk alleles on IL4RA and IL4. In relation to OS, a highly significant interaction was observed in DLBCL for IL4RA (rs1805010 * IL10 (rs1800890 (HR = 0.11 (0.02-0.50. Finally, we explored the expression of risk genes from the gene-gene interaction analysis in normal B-cell subtypes showing a different expression of IL4RA, IL10, IL10RB genes supporting a pathogenetic effect of these interactions in the germinal center.The present findings support the importance of inflammatory genes in B-cell lymphomas. We found association between polymorphic sites in inflammatory response genes and risk as well as outcome in B-NHL and suggest an effect of gene-gene interactions during the stepwise oncogenesis.

  8. Bone Mass Density and Risk of Breast Cancer and Survival in Older Women

    International Nuclear Information System (INIS)

    Ganry, O.; Baudoin, C.; Fardellone, P.; Peng, J.; Raverdy, N.

    2004-01-01

    Study objective: Older women with high bone mineral density (BMD) have an increased risk of breast cancer but it is not well known whether this association is associated with the stage of the tumor. The objective of the study is to determine if older women with high BMD are likely to develop a more aggressive form of breast cancer, as defined by mortality. Patients: We prospectively studied 1504 women who were 75 years of age or older at the entry in the study (range, 75-90 years), between 1992 and 1994. BMD was measured by dual-photon X-ray absorptiometry at three skeletal sites (trochanter, Ward's triangle, femoral neck). The women were followed for a mean of 7 years for the occurrence of breast cancer. Cox proportional-hazards models were used to obtain estimates of the relative risk of breast cancer and relative risk of death according to the BMD. Main results: Forty-five incident breast cancer cases were identified. In multivariate analyses of the risk of breast cancer for women in the highest tertile of BMD was greater than for women in the lowest tertile. Indeed, the women with a trochanter BMD in the highest tertile were at 2.3-fold increased risk compared with women in the lowest tertile. The women with highest tertile BMD measured at the Ward's triangle and at the femoral neck were respectively at 2.2-and 3.3-fold increased risk compared with women at the lowest risk. The 7-year survival rates were markedly less favorable for women in the second and third tertile of the three skeletal sites compared with the lowest tertile. The risk of death was greater for women in the highest tertile of BMD than for women in the lowest tertile at every skeletal site. Conclusion: Elderly women with high BMD have an increased risk of breast cancer, especially advanced cancer, compared with women with low BMD

  9. Support vector methods for survival analysis: a comparison between ranking and regression approaches.

    Science.gov (United States)

    Van Belle, Vanya; Pelckmans, Kristiaan; Van Huffel, Sabine; Suykens, Johan A K

    2011-10-01

    To compare and evaluate ranking, regression and combined machine learning approaches for the analysis of survival data. The literature describes two approaches based on support vector machines to deal with censored observations. In the first approach the key idea is to rephrase the task as a ranking problem via the concordance index, a problem which can be solved efficiently in a context of structural risk minimization and convex optimization techniques. In a second approach, one uses a regression approach, dealing with censoring by means of inequality constraints. The goal of this paper is then twofold: (i) introducing a new model combining the ranking and regression strategy, which retains the link with existing survival models such as the proportional hazards model via transformation models; and (ii) comparison of the three techniques on 6 clinical and 3 high-dimensional datasets and discussing the relevance of these techniques over classical approaches fur survival data. We compare svm-based survival models based on ranking constraints, based on regression constraints and models based on both ranking and regression constraints. The performance of the models is compared by means of three different measures: (i) the concordance index, measuring the model's discriminating ability; (ii) the logrank test statistic, indicating whether patients with a prognostic index lower than the median prognostic index have a significant different survival than patients with a prognostic index higher than the median; and (iii) the hazard ratio after normalization to restrict the prognostic index between 0 and 1. Our results indicate a significantly better performance for models including regression constraints above models only based on ranking constraints. This work gives empirical evidence that svm-based models using regression constraints perform significantly better than svm-based models based on ranking constraints. Our experiments show a comparable performance for methods

  10. Credit Risk Evaluation : Modeling - Analysis - Management

    OpenAIRE

    Wehrspohn, Uwe

    2002-01-01

    An analysis and further development of the building blocks of modern credit risk management: -Definitions of default -Estimation of default probabilities -Exposures -Recovery Rates -Pricing -Concepts of portfolio dependence -Time horizons for risk calculations -Quantification of portfolio risk -Estimation of risk measures -Portfolio analysis and portfolio improvement -Evaluation and comparison of credit risk models -Analytic portfolio loss distributions The thesis contributes to the evaluatio...

  11. Bayesian Analysis for EMP Survival Probability of Solid State Relay

    International Nuclear Information System (INIS)

    Sun Beiyun; Zhou Hui; Cheng Xiangyue; Mao Congguang

    2009-01-01

    The principle to estimate the parameter p of binomial distribution by Bayesian method and the several non-informative prior are introduced. The survival probability of DC solid state relay under current injection at certain amplitude is obtained by this method. (authors)

  12. A comparative study of machine learning methods for time-to-event survival data for radiomics risk modelling.

    Science.gov (United States)

    Leger, Stefan; Zwanenburg, Alex; Pilz, Karoline; Lohaus, Fabian; Linge, Annett; Zöphel, Klaus; Kotzerke, Jörg; Schreiber, Andreas; Tinhofer, Inge; Budach, Volker; Sak, Ali; Stuschke, Martin; Balermpas, Panagiotis; Rödel, Claus; Ganswindt, Ute; Belka, Claus; Pigorsch, Steffi; Combs, Stephanie E; Mönnich, David; Zips, Daniel; Krause, Mechthild; Baumann, Michael; Troost, Esther G C; Löck, Steffen; Richter, Christian

    2017-10-16

    Radiomics applies machine learning algorithms to quantitative imaging data to characterise the tumour phenotype and predict clinical outcome. For the development of radiomics risk models, a variety of different algorithms is available and it is not clear which one gives optimal results. Therefore, we assessed the performance of 11 machine learning algorithms combined with 12 feature selection methods by the concordance index (C-Index), to predict loco-regional tumour control (LRC) and overall survival for patients with head and neck squamous cell carcinoma. The considered algorithms are able to deal with continuous time-to-event survival data. Feature selection and model building were performed on a multicentre cohort (213 patients) and validated using an independent cohort (80 patients). We found several combinations of machine learning algorithms and feature selection methods which achieve similar results, e.g. C-Index = 0.71 and BT-COX: C-Index = 0.70 in combination with Spearman feature selection. Using the best performing models, patients were stratified into groups of low and high risk of recurrence. Significant differences in LRC were obtained between both groups on the validation cohort. Based on the presented analysis, we identified a subset of algorithms which should be considered in future radiomics studies to develop stable and clinically relevant predictive models for time-to-event endpoints.

  13. Comparison of cardiovascular risk factors and survival in patients with ischemic or hemorrhagic stroke.

    Science.gov (United States)

    Henriksson, Karin M; Farahmand, Bahman; Åsberg, Signild; Edvardsson, Nils; Terént, Andreas

    2012-06-01

    Differences in risk factor profiles between patients with ischemic and hemorrhagic stroke may have an impact on subsequent mortality. To explore cardiovascular disease risk factors, including the CHADS(2) score, with survival after ischemic or hemorrhagic stroke. Between 2001 and 2005, 87 111 (83%) ischemic stroke, 12 497 (12%) hemorrhagic stroke, and 5435 (5%) patients with unspecified stroke were identified in the Swedish Stroke Register. Data on gender, age, and cardiovascular disease risk factors were linked to the Swedish Hospital Discharge and Cause of Death Registers. Adjusted odds and hazard ratios and 95% confidence interval were calculated using logistic and Cox proportional hazard regression models. Hemorrhagic stroke patients were younger than ischemic stroke patients. All cardiovascular disease risk factors studied, alone or combined in the CHADS(2) score, were associated with higher odds ratios for ischemic stroke vs. hemorrhagic stroke. Higher CHADS(2) scores and all studied risk factors except hypertension were associated with higher odds ratio for death by ischemic stroke than hemorrhagic stroke. Ischemic stroke was associated with lower early mortality (within 30 days) vs. hemorrhagic stroke (hazard ratio = 0·28, confidence interval 0·27 to 0·29). Patients with hemorrhagic stroke had a higher risk of dying within the first 30 days after stroke, but the risk of death was similar in the two groups after one-month. Hypertension was the only cardiovascular disease risk factor associated with an increased mortality rate for hemorrhagic stroke as compared to ischemic stroke. © 2011 The Authors. International Journal of Stroke © 2011 World Stroke Organization.

  14. γ-amino butyric acid (GABA) level as an overall survival risk factor in breast cancer.

    Science.gov (United States)

    Brzozowska, Anna; Burdan, Franciszek; Duma, Dariusz; Solski, Janusz; Mazurkiewicz, Maria

    2017-09-21

    The γ-amino butyric acid (GABA) plays important role in the proliferation and migration of cancer cells. The aim of the study was to evaluate the level of GABA in breast cancer, in relation to clinical and epidemiological data. The study was conducted on 89 patients with breast cancer in stage I-II. GABA level was assessed using spectrofluorometric method in tumour homogenates. Immunoexpression of E-cadherin was evaluated histologically on paraffin fixed specimens. Overall and disease-free survival was assessed for a 15-year interval period. Median overall survival was significantly longer (127.2 months) in patients with a high level of GABA (>89.3 μg/1), compared with a group with a low level of the amino acid (106.4 months). Disease-free survival was insignificantly different - 99 and 109 months, respectively. A significantly longer overall survival (131.2 months) was seen among patients with a high level of GABA and positive E-cadherin immunoexpression, compared with a group characterized by a low level of GABA and lack of E-cadherin immunorectivity (98.1 months). The co-existence of negative immunoexpression of E-cadherin and low GABA concentration resulted in a six-fold increase in the risk of death (HR=6.03). GABA has a significant prognostic value in breast cancer. Co-existence of a low level of GABA and loss of E-cadherin immune-expression seems to be a new, independent, and negative prognostic marker of the neoplasm.

  15. Bot fly parasitism of the red-backed vole: host survival, infection risk, and population growth.

    Science.gov (United States)

    Lemaître, Jérôme; Fortin, Daniel; Montiglio, Pierre-Olivier; Darveau, Marcel

    2009-03-01

    Parasites can play an important role in the dynamics of host populations, but empirical evidence remains sparse. We investigated the role of bot fly (Cuterebra spp.) parasitism in red-backed voles (Myodes gapperi) by first assessing the impacts of the parasite on the probability of vole survival under stressful conditions as well as on the reproductive activity of females. We then identified the main factors driving both the individual risk of infection and the abundance of bot flies inside red-backed voles. Finally, we evaluated the impacts of bot fly prevalence on the growth rate of vole populations between mid-July and mid-August. Thirty-six populations of red-backed voles were sampled in the boreal forest of Québec, Canada. The presence and the abundance of parasites in voles, two host life history traits (sex and body condition), three indices of habitat complexity (tree basal area, sapling basal area, coarse woody debris volume), and vole abundance were considered in models evaluating the effects of bot flies on host populations. We found that the probability of survival of red-backed voles in live traps decreased with bot fly infection. Both the individual risk of infection and the abundance of bot flies in red-backed voles were driven mainly by vole abundance rather than by the two host life history traits or the three variables of habitat complexity. Parasitism had population consequences: bot fly prevalence was linked to a decrease in short-term growth rate of vole populations over the summer. We found that bot flies have the potential to reduce survival of red-backed voles, an effect that may apply to large portions of populations.

  16. Risk Analysis in Road Tunnels – Most Important Risk Indicators

    DEFF Research Database (Denmark)

    Berchtold, Florian; Knaust, Christian; Thöns, Sebastian

    2016-01-01

    Methodologies on fire risk analysis in road tunnels consider numerous factors affecting risks (risk indicators) and express the results by risk measures. But only few comprehensive studies on effects of risk indicators on risk measures are available. For this reason, this study quantifies...... the effects and highlights the most important risk indicators with the aim to support further developments in risk analysis. Therefore, a system model of a road tunnel was developed to determine the risk measures. The system model can be divided into three parts: the fire part connected to the fire model Fire...... Dynamics Simulator (FDS); the evacuation part connected to the evacuation model FDS+Evac; and the frequency part connected to a model to calculate the frequency of fires. This study shows that the parts of the system model (and their most important risk indicators) affect the risk measures in the following...

  17. Risk as analysis and risk as feelings: some thoughts about affect, reason, risk, and rationality.

    Science.gov (United States)

    Slovic, Paul; Finucane, Melissa L; Peters, Ellen; MacGregor, Donald G

    2004-04-01

    Modern theories in cognitive psychology and neuroscience indicate that there are two fundamental ways in which human beings comprehend risk. The "analytic system" uses algorithms and normative rules, such as probability calculus, formal logic, and risk assessment. It is relatively slow, effortful, and requires conscious control. The "experiential system" is intuitive, fast, mostly automatic, and not very accessible to conscious awareness. The experiential system enabled human beings to survive during their long period of evolution and remains today the most natural and most common way to respond to risk. It relies on images and associations, linked by experience to emotion and affect (a feeling that something is good or bad). This system represents risk as a feeling that tells us whether it is safe to walk down this dark street or drink this strange-smelling water. Proponents of formal risk analysis tend to view affective responses to risk as irrational. Current wisdom disputes this view. The rational and the experiential systems operate in parallel and each seems to depend on the other for guidance. Studies have demonstrated that analytic reasoning cannot be effective unless it is guided by emotion and affect. Rational decision making requires proper integration of both modes of thought. Both systems have their advantages, biases, and limitations. Now that we are beginning to understand the complex interplay between emotion and reason that is essential to rational behavior, the challenge before us is to think creatively about what this means for managing risk. On the one hand, how do we apply reason to temper the strong emotions engendered by some risk events? On the other hand, how do we infuse needed "doses of feeling" into circumstances where lack of experience may otherwise leave us too "coldly rational"? This article addresses these important questions.

  18. Risk analysis for autonomous underwater vehicle operations in extreme environments.

    Science.gov (United States)

    Brito, Mario Paulo; Griffiths, Gwyn; Challenor, Peter

    2010-12-01

    Autonomous underwater vehicles (AUVs) are used increasingly to explore hazardous marine environments. Risk assessment for such complex systems is based on subjective judgment and expert knowledge as much as on hard statistics. Here, we describe the use of a risk management process tailored to AUV operations, the implementation of which requires the elicitation of expert judgment. We conducted a formal judgment elicitation process where eight world experts in AUV design and operation were asked to assign a probability of AUV loss given the emergence of each fault or incident from the vehicle's life history of 63 faults and incidents. After discussing methods of aggregation and analysis, we show how the aggregated risk estimates obtained from the expert judgments were used to create a risk model. To estimate AUV survival with mission distance, we adopted a statistical survival function based on the nonparametric Kaplan-Meier estimator. We present theoretical formulations for the estimator, its variance, and confidence limits. We also present a numerical example where the approach is applied to estimate the probability that the Autosub3 AUV would survive a set of missions under Pine Island Glacier, Antarctica in January-March 2009. © 2010 Society for Risk Analysis.

  19. What is a risk. [Quantitative risk analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schoen, G [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany, F.R.)

    1979-02-01

    The following article is a revised version of a lecture given by the author during the VDE meeting 'Technical Expert Activities' in Brunswick. First of all, the concept of 'risk' is discussed which leads to a probability scale which then permits a definition of the 'justifiable risk' as the boundary between 'hazard' and 'safety'. The boundary is quantified indirectly from laws, regulations, instructions, etc. to the 'Technological rules' for special fields of application by minimum requirement data. These viewpoints described in detail are not only of substantial significance for the creation of safety regulations but also for their application and consequently for jurisdiction.

  20. Advanced Online Survival Analysis Tool for Predictive Modelling in Clinical Data Science.

    Science.gov (United States)

    Montes-Torres, Julio; Subirats, José Luis; Ribelles, Nuria; Urda, Daniel; Franco, Leonardo; Alba, Emilio; Jerez, José Manuel

    2016-01-01

    One of the prevailing applications of machine learning is the use of predictive modelling in clinical survival analysis. In this work, we present our view of the current situation of computer tools for survival analysis, stressing the need of transferring the latest results in the field of machine learning to biomedical researchers. We propose a web based software for survival analysis called OSA (Online Survival Analysis), which has been developed as an open access and user friendly option to obtain discrete time, predictive survival models at individual level using machine learning techniques, and to perform standard survival analysis. OSA employs an Artificial Neural Network (ANN) based method to produce the predictive survival models. Additionally, the software can easily generate survival and hazard curves with multiple options to personalise the plots, obtain contingency tables from the uploaded data to perform different tests, and fit a Cox regression model from a number of predictor variables. In the Materials and Methods section, we depict the general architecture of the application and introduce the mathematical background of each of the implemented methods. The study concludes with examples of use showing the results obtained with public datasets.

  1. Finding Risk Groups by Optimizing Artificial Neural Networks on the Area under the Survival Curve Using Genetic Algorithms.

    Science.gov (United States)

    Kalderstam, Jonas; Edén, Patrik; Ohlsson, Mattias

    2015-01-01

    We investigate a new method to place patients into risk groups in censored survival data. Properties such as median survival time, and end survival rate, are implicitly improved by optimizing the area under the survival curve. Artificial neural networks (ANN) are trained to either maximize or minimize this area using a genetic algorithm, and combined into an ensemble to predict one of low, intermediate, or high risk groups. Estimated patient risk can influence treatment choices, and is important for study stratification. A common approach is to sort the patients according to a prognostic index and then group them along the quartile limits. The Cox proportional hazards model (Cox) is one example of this approach. Another method of doing risk grouping is recursive partitioning (Rpart), which constructs a decision tree where each branch point maximizes the statistical separation between the groups. ANN, Cox, and Rpart are compared on five publicly available data sets with varying properties. Cross-validation, as well as separate test sets, are used to validate the models. Results on the test sets show comparable performance, except for the smallest data set where Rpart's predicted risk groups turn out to be inverted, an example of crossing survival curves. Cross-validation shows that all three models exhibit crossing of some survival curves on this small data set but that the ANN model manages the best separation of groups in terms of median survival time before such crossings. The conclusion is that optimizing the area under the survival curve is a viable approach to identify risk groups. Training ANNs to optimize this area combines two key strengths from both prognostic indices and Rpart. First, a desired minimum group size can be specified, as for a prognostic index. Second, the ability to utilize non-linear effects among the covariates, which Rpart is also able to do.

  2. Postmastectomy radiotherapy improves disease-free survival of high risk of locoregional recurrence breast cancer patients with T1-2 and 1 to 3 positive nodes.

    Directory of Open Access Journals (Sweden)

    Zhen-Yu He

    Full Text Available The indications for post-mastectomy radiotherapy (PMRT with T1-2 breast cancer and 1-3 positive axillary lymph nodes is still controversial. The purpose of this study was to investigate the role of PMRT in T1-2 breast cancer with 1-3 positive axillary lymph node.We retrospectively reviewed the file records of 79 patients receiving PMRT and not receiving PMRT (618 patients.The median follow-up was 65 months. Multivariate analysis showed that PMRT was an independent prognostic factor of locoregional recurrence-free survival (LRFS (P = 0.010. Subgroup analysis of patients who did not undergo PMRT showed that pT stage, number of positive axillary lymph nodes, and molecular subtype were independent prognostic factors of LRFS. PMRT improved LRFS in the entire group (P = 0.005, but did not affect distant metastasis-free survival (DMFS (P = 0.494, disease-free survival (DFS (P = 0.215, and overall survival (OS (P = 0.645. For patients without PMRT, the 5-year LRFS of low-risk patients (0-1 risk factor for locoregional recurrence of 94.5% was significantly higher than that of high-risk patients (2-3 risk factors for locoregional recurrence (80.9%, P < 0.001. PMRT improved LRFS (P = 0.001 and DFS (P = 0.027 in high-risk patients, but did not improve LRFS, DMFS, DFS, and OS in low-risk patients.PMRT is beneficial in patients with high risk of locoregional recurrence breast cancer patients with T1-2 and 1 to 3 positive nodes.

  3. Risk analysis in radiosurgery treatments using risk matrices

    International Nuclear Information System (INIS)

    Delgado, J. M.; Sanchez Cayela, C.; Ramirez, M. L.; Perez, A.

    2011-01-01

    The aim of this study is the risk analysis process stereotactic single-dose radiotherapy and evaluation of those initiating events that lead to increased risk and a possible solution in the design of barriers.

  4. «Esa corporeidad mortal y rosa»: análisis del tiempo libre de enfermedad del cáncer de mama en Gipuzkoa en presencia de riesgos competitivos "That deadly and pink corporeity": Analysis of disease-free survival analysis in breast cancer in Gipuzkoa (Spain in the presence of competing risks

    Directory of Open Access Journals (Sweden)

    Pablo Martínez-Camblor

    2009-12-01

    sobrestimación tanto de la probabilidad de recidiva como de la mortalidad debida a la enfermedad.Objective: To analyze time of disease-free survival and relative survival in women diagnosed with breast cancer in the province of Gipuzkoa within the context of competing risks by assessing differences between the direct use of the Kaplan-Meier estimator and the multiple decrement method on the one hand, and relative survival on the other. Methods: All registered breast cancer cases in Gipuzkoa in 1995 and 1996 with stages other than stage IV were included. An 8-year follow-up for recurrence and a 10-year follow-up for survival were performed. Time of disease-free survival was studied by the multiple decrement model. Observed survival and survival corrected by the expected mortality in the population (relative survival were also studied. Results: Estimation of the probability of recurrence at 8 years with the multiple decrement method was 8.8% lower than that obtained with the Kaplan-Meier method. The difference between the observed and relative survival rates at 10 years was 10.8%. Both results show how, in this case, the Kaplan-Meier estimator overestimates both the probability of recurrence and that of mortality from the disease. Conclusions: Two issues are often overlooked when performing survival analyses: firstly, because of the lack of independence between survival time and censoring time, the results obtained by the Kaplan-Meier estimator are uninterpretable; secondly, it is an incontrovertible fact that one way or another, everyone causes failures. In this approach, survival analyses must take into account the probability of failure in the general population of reference. The results obtained in this study show that superficial use of the Kaplan Meier estimator overestimates both the probability of recurrence and that of mortality caused by the disease.

  5. Survival Analysis of Occipital Nerve Stimulator Leads Placed under Fluoroscopic Guidance with and without Ultrasonography.

    Science.gov (United States)

    Jones, James H; Brown, Alison; Moyse, Daniel; Qi, Wenjing; Roy, Lance

    2017-11-01

    Electrical stimulation of the greater occipital nerves is performed to treat pain secondary to chronic daily headaches and occipital neuralgia. The use of fluoroscopy alone to guide the surgical placement of electrodes near the greater occipital nerves disregards the impact of tissue planes on lead stability and stimulation efficacy. We hypothesized that occipital neurostimulator (ONS) leads placed with ultrasonography combined with fluoroscopy would demonstrate increased survival rates and times when compared to ONS leads placed with fluoroscopy alone. A 2-arm retrospective chart review. A single academic medical center. This retrospective chart review analyzed the procedure notes and demographic data of patients who underwent the permanent implant of an ONS lead between July 2012 and August 2015. Patient data included the diagnosis (reason for implant), smoking tobacco use, disability, and age. ONS lead data included the date of permanent implant, the imaging modality used during permanent implant (fluoroscopy with or without ultrasonography), and, if applicable, the date and reason for lead removal. A total of 21 patients (53 leads) were included for the review. Chi-squared tests, Fishers exact tests, 2-sample t-tests, and Wilcoxon rank-sum tests were used to compare fluoroscopy against combined fluoroscopy and ultrasonography as implant methods with respect to patient demographics. These tests were also used to evaluate the primary aim of this study, which was to compare the survival rates and times of ONS leads placed with combined ultrasonography and fluoroscopy versus those placed with fluoroscopy alone. Survival analysis was used to assess the effect of implant method, adjusted for patient demographics (age, smoking tobacco use, and disability), on the risk of lead explant. Data from 21 patients were collected, including a total of 53 ONS leads. There was no statistically significant difference in the lead survival rate or time, disability, or patient age

  6. Is complete resection of high-risk stage IV neuroblastoma associated with better survival?

    Science.gov (United States)

    Yeung, Fanny; Chung, Patrick Ho Yu; Tam, Paul Kwong Hang; Wong, Kenneth Kak Yuen

    2015-12-01

    The role of surgery in the management of stage IV neuroblastoma is controversial. In this study, we attempted to study if complete tumor resection had any impact on event-free survival (EFS) and overall survival (OS). A retrospective analysis of patients with stage IV neuroblastoma between November 2000 and July 2014 in a tertiary referral center was performed. Demographics data, extent of surgical resection, and outcomes were analyzed. A total of 34 patients with stage IV neuroblastoma according to International Neuroblastoma Staging System (INSS) were identified. The median age at diagnosis and operation was 3.5 (±1.9) years and 3.8 (±2.0) years, respectively. Complete gross tumor resection (CTR) was achieved in twenty-four patients (70.1%), in which one of the patients had nephrectomy and another had distal pancreatectomy. Gross total resection (GTR) with removal of >95% of tumor was performed in six patients (17.6%) and subtotal tumor resection (STR) with removal of >50%, but <95% of tumor was performed in four patients (11.8%). There was no statistical significance in terms of 5-year EFS and OS among the 3 groups. There was no surgery-related mortality or morbidity. From our center's experience, as there was no substantial survival benefit in stage IV neuroblastoma patients undergoing complete tumor resection, organ preservation and minimalization of morbidity should also be taken into consideration. Copyright © 2015. Published by Elsevier Inc.

  7. High-risk human papilloma virus (HPV) and survival in patients with esophageal carcinoma: a pilot study

    International Nuclear Information System (INIS)

    Dreilich, Martin; Bergqvist, Michael; Moberg, Martin; Brattström, Daniel; Gustavsson, Inger; Bergström, Stefan; Wanders, Alkwin; Hesselius, Patrik; Wagenius, Gunnar; Gyllensten, Ulf

    2006-01-01

    Human papilloma virus (HPV) in patients with esophageal carcinoma has previously been studied with an average detection rate of 15%, but the role of HPV in relation to survival is less clear. In cervical cancer, lung cancer and tonsil cancer HPV viral load is a predictive factor for survival and outcome of treatment. The primary aim was to study the spectrum of high-risk HPV types in esophageal tumors. Secondary, as a pilot study we investigated the association between HPV status and the survival rates. We compared both the presence and the viral load of high-risk HPV types 16, 18, 31, 33, 39, 45, 52, 58, and 67 in relation to clinical data from patients with esophageal carcinoma. Survival data and tumor samples were retrieved from 100 patients receiving treatment at the Department of Oncology, Uppsala Hospital, Uppsala, Sweden. The tumor samples were investigated for HPV viral load using real-time PCR. HPV 16 was detected in 16% of the patients; no other HPV type was detected. HPV 16 infection had no significant effect on survival (p = 0.72). Also, HPV 16 did not improve survival after treatment (radiotherapy or chemotherapy). Only HPV 16 was detected among the patients. HPV 16 in esophageal carcinoma patients did not influence survival or improve therapy response. However, given the size of the study there is a need to examine a larger cohort in order to understand in more detail the effect of high risk HPV types in esophageal carcinoma

  8. Chemotherapy increases long-term survival in patients with adult medulloblastoma--a literature-based meta-analysis.

    Science.gov (United States)

    Kocakaya, Selin; Beier, Christoph Patrick; Beier, Dagmar

    2016-03-01

    Adult medulloblastoma is a potentially curable malignant entity with an incidence of 0.5-1 per million. Valid data on prognosis, treatment, and demographics are lacking, as most current knowledge stems from retrospective studies. Surgical resection followed by radiotherapy are accepted parts of treatment regimes; however, established prognostic factors and data clarifying the role of chemotherapy are missing. We investigated 227 publications from 1969-2013, with 907 identifiable, individual patients being available for meta-analysis. Demographic data, risk stratification, and treatment of these patients were similar to previous cohorts. The median overall survival (mOS) was 65 months (95% CI: 54.6-75.3) , the 5-year overall survival was 50.9% with 16% of the patients dying more than 5 years after diagnosis. Incomplete resection, clinical and radiological signs for brainstem infiltration, and abstinence from radiotherapy were predictive of worse outcome. Metastatic disease at tumor recurrence was identified as a new prognostic factor, while neither metastasis at initial diagnosis nor desmoplastic/classic histology was correlated with survival. Patients receiving chemotherapy first-line survived significantly longer (mOS: 108 mo, 95% CI: 68.6-148.4) than patients treated with radiation alone (mOS: 57 mo, 95% CI: 39.6-74.4) or patients who received chemotherapy at tumor recurrence. This effect was not biased by tumor stage or decade of treatment. Importantly, (neo)adjuvant chemotherapy also significantly increased the chance for long-term survival (>5 y) compared with radiotherapy alone or chemotherapy at tumor recurrence. This meta-analysis clarifies relevant prognostic factors and suggests that chemotherapy as part of first-line therapy improves overall survival and increases the proportion of patients with long-term survival. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions

  9. The tourism and travel industry and its effect on the Great Recession: A multilevel survival analysis

    Directory of Open Access Journals (Sweden)

    Zdravko Šergo

    2017-12-01

    Full Text Available Does a country with a heavy dependence on a tourism economy have a tendency to succumb to more risk in a recession? With the shift from manufacturing-based economies in the developing world toward service-based industries, including tourism, a reliance on the tourism industry may erode economic stability in tourism-based countries, making them more prone to fall into a recession due to higher risks. In this paper, we wish to emphasise the positive impact of tourism specialisation indices in the international economy on the probability occurrence of a so-called Great Recession. This article uses a multilevel survival analysis and a generalised linear mixed-effect (GLMM structure modelling to investigate the impact of tourism development on the probability of recession frequency (risk in terms of months of duration and severity, by using data collected from 2007 to 2013 from 71 countries around the world, to see if recession frequency is positively correlated with the various indicators of tourism development. Two GLMMs were fitted to this data: logistic regression and count regression with a Poisson distribution. Results for both regressions show considerable evidence that the ratio between the number of overnight stays and the resident population and travel services as a percentage of commercial service exports positively impacts the probability for a country (from our sample to experience a recession event and can make recession worse in terms of severity, measured in months.

  10. Development and external validation of a risk-prediction model to predict 5-year overall survival in advanced larynx cancer

    NARCIS (Netherlands)

    Petersen, Japke F.; Stuiver, Martijn M.; Timmermans, Adriana J.; Chen, Amy; Zhang, Hongzhen; O'Neill, James P.; Deady, Sandra; Vander Poorten, Vincent; Meulemans, Jeroen; Wennerberg, Johan; Skroder, Carl; Day, Andrew T.; Koch, Wayne; van den Brekel, Michiel W. M.

    2017-01-01

    TNM-classification inadequately estimates patient-specific overall survival (OS). We aimed to improve this by developing a risk-prediction model for patients with advanced larynx cancer. Cohort study. We developed a risk prediction model to estimate the 5-year OS rate based on a cohort of 3,442

  11. Risk Analysis Group annual progress report 1984

    International Nuclear Information System (INIS)

    1985-06-01

    The activities of the Risk Analysis Group at Risoe during 1984 are presented. These include descriptions in some detail of work on general development topics and risk analysis performed as contractor. (author)

  12. Meta-analysis of single-arm survival studies: a distribution-free approach for estimating summary survival curves with random effects.

    Science.gov (United States)

    Combescure, Christophe; Foucher, Yohann; Jackson, Daniel

    2014-07-10

    In epidemiologic studies and clinical trials with time-dependent outcome (for instance death or disease progression), survival curves are used to describe the risk of the event over time. In meta-analyses of studies reporting a survival curve, the most informative finding is a summary survival curve. In this paper, we propose a method to obtain a distribution-free summary survival curve by expanding the product-limit estimator of survival for aggregated survival data. The extension of DerSimonian and Laird's methodology for multiple outcomes is applied to account for the between-study heterogeneity. Statistics I(2)  and H(2) are used to quantify the impact of the heterogeneity in the published survival curves. A statistical test for between-strata comparison is proposed, with the aim to explore study-level factors potentially associated with survival. The performance of the proposed approach is evaluated in a simulation study. Our approach is also applied to synthesize the survival of untreated patients with hepatocellular carcinoma from aggregate data of 27 studies and synthesize the graft survival of kidney transplant recipients from individual data from six hospitals. Copyright © 2014 John Wiley & Sons, Ltd.

  13. RISK ANALYSIS IN MILK PROCESSING

    Directory of Open Access Journals (Sweden)

    I. PIRVUTOIU

    2008-05-01

    Full Text Available This paper aimed to evaluate Risk bankruptcy using “Score Method” based on Canon and Holder’s Model. The data were collected from the Balance Sheet and Profit and Loss Account for the period 2005-2007, recorded by a Meat processing Plant (Rador Commercial Company .The study has put in evidence the financial situation of the company,the level of the main financial ratios fundamenting the calculation of Z score function value in the three years The low values of Z score function recorded every year reflects that the company is still facing backruptcy. However , the worst situation was recorded in the years 2005 and 2006, when baknruptcy risk was ranging between 70 – 80 % . In the year 2007, the risk bankruptcy was lower, ranging between 50-70 % , as Z function recorded a value lower than 4 .For Meat processing companies such an analysis is compulsory at present as long as business environment is very risky in our country.

  14. Adjuvant Sunitinib for High-risk Renal Cell Carcinoma After Nephrectomy: Subgroup Analyses and Updated Overall Survival Results.

    Science.gov (United States)

    Motzer, Robert J; Ravaud, Alain; Patard, Jean-Jacques; Pandha, Hardev S; George, Daniel J; Patel, Anup; Chang, Yen-Hwa; Escudier, Bernard; Donskov, Frede; Magheli, Ahmed; Carteni, Giacomo; Laguerre, Brigitte; Tomczak, Piotr; Breza, Jan; Gerletti, Paola; Lechuga, Mariajose; Lin, Xun; Casey, Michelle; Serfass, Lucile; Pantuck, Allan J; Staehler, Michael

    2018-01-01

    Adjuvant sunitinib significantly improved disease-free survival (DFS) versus placebo in patients with locoregional renal cell carcinoma (RCC) at high risk of recurrence after nephrectomy (hazard ratio [HR] 0.76, 95% confidence interval [CI] 0.59-0.98; p=0.03). To report the relationship between baseline factors and DFS, pattern of recurrence, and updated overall survival (OS). Data for 615 patients randomized to sunitinib (n=309) or placebo (n=306) in the S-TRAC trial. Subgroup DFS analyses by baseline risk factors were conducted using a Cox proportional hazards model. Baseline risk factors included: modified University of California Los Angeles integrated staging system criteria, age, gender, Eastern Cooperative Oncology Group performance status (ECOG PS), weight, neutrophil-to-lymphocyte ratio (NLR), and Fuhrman grade. Of 615 patients, 97 and 122 in the sunitinib and placebo arms developed metastatic disease, with the most common sites of distant recurrence being lung (40 and 49), lymph node (21 and 26), and liver (11 and 14), respectively. A benefit of adjuvant sunitinib over placebo was observed across subgroups, including: higher risk (T3, no or undetermined nodal involvement, Fuhrman grade ≥2, ECOG PS ≥1, T4 and/or nodal involvement; hazard ratio [HR] 0.74, 95% confidence interval [CI] 0.55-0.99; p=0.04), NLR ≤3 (HR 0.72, 95% CI 0.54-0.95; p=0.02), and Fuhrman grade 3/4 (HR 0.73, 95% CI 0.55-0.98; p=0.04). All subgroup analyses were exploratory, and no adjustments for multiplicity were made. Median OS was not reached in either arm (HR 0.92, 95% CI 0.66-1.28; p=0.6); 67 and 74 patients died in the sunitinib and placebo arms, respectively. A benefit of adjuvant sunitinib over placebo was observed across subgroups. The results are consistent with the primary analysis, which showed a benefit for adjuvant sunitinib in patients at high risk of recurrent RCC after nephrectomy. Most subgroups of patients at high risk of recurrent renal cell carcinoma after

  15. Surviving global risks through the preservation of humanity's data on the Moon

    Science.gov (United States)

    Turchin, Alexey; Denkenberger, David

    2018-05-01

    Many global catastrophic risks are threatening human civilization, and a number of ideas have been suggested for preventing or surviving them. However, if these interventions fail, society could preserve information about the human race and human DNA samples in the hopes that the next civilization on Earth will be able to reconstruct Homo sapiens and our culture. This requires information preservation of an order of magnitude of 100 million years, a little-explored topic thus far. It is important that a potential future civilization discovers this information as early as possible, thus a beacon should accompany the message in order to increase visibility. The message should ideally contain information about how humanity was destroyed, perhaps including a continuous recording until the end. This could help the potential future civilization to survive. The best place for long-term data storage is under the surface of the Moon, with the beacon constructed as a complex geometric figure drawn by small craters or trenches around a central point. There are several cost-effective options for sending the message as opportunistic payloads on different planned landers.

  16. Analysis of survival data with dependent censoring copula-based approaches

    CERN Document Server

    Emura, Takeshi

    2018-01-01

    This book introduces readers to copula-based statistical methods for analyzing survival data involving dependent censoring. Primarily focusing on likelihood-based methods performed under copula models, it is the first book solely devoted to the problem of dependent censoring. The book demonstrates the advantages of the copula-based methods in the context of medical research, especially with regard to cancer patients’ survival data. Needless to say, the statistical methods presented here can also be applied to many other branches of science, especially in reliability, where survival analysis plays an important role. The book can be used as a textbook for graduate coursework or a short course aimed at (bio-) statisticians. To deepen readers’ understanding of copula-based approaches, the book provides an accessible introduction to basic survival analysis and explains the mathematical foundations of copula-based survival models.

  17. Risk analysis; Analisis de riesgos

    Energy Technology Data Exchange (ETDEWEB)

    Baron, J H; Nunez McLeod, J; Rivera, S S [Universidad Nacional de Cuyo, Mendoza (Argentina). Instituto de Capacitacion Especial y Desarrollo de Ingenieria Asistida por Computadora (CEDIAC)

    1997-07-01

    This book contains a selection of research works performed in the CEDIAC Institute (Cuyo National University) in the area of Risk Analysis, with specific orientations to the subjects of uncertainty and sensitivity studies, software reliability, severe accident modeling, etc. This volume presents important material for all those researches who want to have an insight in the risk analysis field, as a tool to solution several problems frequently found in the engineering and applied sciences field, as well as for the academic teachers who want to keep up to date, including the new developments and improvements continuously arising in this field. [Spanish] Este libro contiene una seleccion de trabajos de investigacion realizados dentro del Instituto de Capacitacion Especial y Desarrollo de la Ingenieria Asistida por Computadora en el area del analisis de riesgos, con una orientacion hacia el estudio de incertidumbres y sensibilidad, confiabilidad de software, modelacion de accidentes severos, etc. Este volumen recoge un material de indudable importancia e interes para todos aquellos investigadores y profesionales que desean incursionar en este campo del analisis de riesgos como herramienta para la solucion de problemas frecuentemente encontrados en la ingenieria y las ciencias aplicadas, asi como para los academicos que desean mantenerse al dia, conociendo los nuevos desarrollos y tecnicas que constantemente aparecen en su area.

  18. A background to risk analysis. Vol. 3

    International Nuclear Information System (INIS)

    Taylor, J.R.

    1979-01-01

    This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques described are somewhat experimental. The report is written in an introductory style, but where some point needs further justifi- cation or evaluation, this is given in the form of a chapter appenix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 3 contains chapters on quantification of risk, failure and accident probability, risk analysis and design, and examles of risk analysis for process plant. (BP)

  19. A background risk analysis. Vol. 1

    International Nuclear Information System (INIS)

    Taylor, J.R.

    1979-01-01

    This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques, described are somewhat experimental. The report is written in an introductory style, but where some point needs further justification or evaluation, this is given in the form of a chapter appendix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 1 contains a short history of risk analysis, and chapters on risk, failures, errors and accidents, and general procedures for risk analysis. (BP)

  20. Lamb survival analysis from birth to weaning in Iranian Kermani sheep.

    Science.gov (United States)

    Barazandeh, Arsalan; Moghbeli, Sadrollah Molaei; Vatankhah, Mahmood; Hossein-Zadeh, Navid Ghavi

    2012-04-01

    Survival records from 1,763 Kermani lambs born between 1996 and 2004 from 294 ewes and 81 rams were used to determine genetic and non-genetic factors affecting lamb survival. Traits included were lamb survival across five periods from birth to 7, 14, 56, 70, and 90 days of age. Traits were analyzed under Weibull proportional hazard sire models. Several binary analyses were also conducted using animal models. Statistical models included the fixed class effects of sex of lamb, month and year of birth, a covariate effect of birth weight, and random genetic effects of both sire (in survival analyses) and animal (in binary analyses). The average survival to 90 days of age was 94.8%. Hazard rates ranged from 1.00 (birth to 90 days of age) to 1.73 (birth to 7 days of age) between the two sexes indicating that male lambs were at higher risk of mortality than females (P lamb survival and lamb birth weight, suggesting that viability and birth weight could be considered simultaneously in the selection programs to obtain optimal birth weight in Kermani lambs. Estimates of heritabilities from survival analyses were medium and ranged from 0.23 to 0.29. In addition, heritability estimates obtained from binary analyses were low and varied from 0.04 to 0.09. The results of this study suggest that progress in survival traits could be possible through managerial strategies and genetic selection.

  1. Reporting and methodological quality of survival analysis in articles published in Chinese oncology journals.

    Science.gov (United States)

    Zhu, Xiaoyan; Zhou, Xiaobin; Zhang, Yuan; Sun, Xiao; Liu, Haihua; Zhang, Yingying

    2017-12-01

    Survival analysis methods have gained widespread use in the filed of oncology. For achievement of reliable results, the methodological process and report quality is crucial. This review provides the first examination of methodological characteristics and reporting quality of survival analysis in articles published in leading Chinese oncology journals.To examine methodological and reporting quality of survival analysis, to identify some common deficiencies, to desirable precautions in the analysis, and relate advice for authors, readers, and editors.A total of 242 survival analysis articles were included to be evaluated from 1492 articles published in 4 leading Chinese oncology journals in 2013. Articles were evaluated according to 16 established items for proper use and reporting of survival analysis.The application rates of Kaplan-Meier, life table, log-rank test, Breslow test, and Cox proportional hazards model (Cox model) were 91.74%, 3.72%, 78.51%, 0.41%, and 46.28%, respectively, no article used the parametric method for survival analysis. Multivariate Cox model was conducted in 112 articles (46.28%). Follow-up rates were mentioned in 155 articles (64.05%), of which 4 articles were under 80% and the lowest was 75.25%, 55 articles were100%. The report rates of all types of survival endpoint were lower than 10%. Eleven of 100 articles which reported a loss to follow-up had stated how to treat it in the analysis. One hundred thirty articles (53.72%) did not perform multivariate analysis. One hundred thirty-nine articles (57.44%) did not define the survival time. Violations and omissions of methodological guidelines included no mention of pertinent checks for proportional hazard assumption; no report of testing for interactions and collinearity between independent variables; no report of calculation method of sample size. Thirty-six articles (32.74%) reported the methods of independent variable selection. The above defects could make potentially inaccurate

  2. Statistical models for competing risk analysis

    International Nuclear Information System (INIS)

    Sather, H.N.

    1976-08-01

    Research results on three new models for potential applications in competing risks problems. One section covers the basic statistical relationships underlying the subsequent competing risks model development. Another discusses the problem of comparing cause-specific risk structure by competing risks theory in two homogeneous populations, P1 and P2. Weibull models which allow more generality than the Berkson and Elveback models are studied for the effect of time on the hazard function. The use of concomitant information for modeling single-risk survival is extended to the multiple failure mode domain of competing risks. The model used to illustrate the use of this methodology is a life table model which has constant hazards within pre-designated intervals of the time scale. Two parametric models for bivariate dependent competing risks, which provide interesting alternatives, are proposed and examined

  3. Bayesian linear regression with skew-symmetric error distributions with applications to survival analysis

    KAUST Repository

    Rubio, Francisco J.; Genton, Marc G.

    2016-01-01

    are censored. The latter scenario is of interest in the context of accelerated failure time models, which are relevant in survival analysis. We present a simulation study that demonstrates good frequentist properties of the posterior credible intervals

  4. HIV testing in the maternity ward and the start of breastfeeding: a survival analysis

    Directory of Open Access Journals (Sweden)

    Glaucia T. Possolli

    2015-08-01

    Full Text Available OBJECTIVE: The purpose of this study was to analyze the factors that influence of the time between birth and the beginning of breastfeeding, especially at the moment of the rapid HIV test results at hospital admission for delivery.METHODS: Cohort study of 932 pregnant women who underwent rapid HIV test admitted in the hospital for delivery in Baby-Friendly Hospitals. The survival curves of time from birth to the first feeding were estimated by the Kaplan-Meier method and the joint effect of independent variables by the Cox model with a hierarchical analysis. As the survival curves were not homogeneous among the five hospitals, hindering the principle of proportionality of risks, the data were divided into two groups according to the median time of onset of breastfeeding at birth in women undergoing rapid HIV testing.RESULTS: Hospitals with median time to breastfeeding onset at birth of up to 60 min were considered as early breastfeeding onset and those with higher medians were considered as late breastfeeding onset at birth. Risk factors common to hospitals considered to be with early and late breastfeeding onset at birth were: cesarean section (RR = 1.75 [95% CI: 1.38-2.22]; RR = 3.83 [95% CI: 3.03-4.85] and rapid test result after birth (RR = 1.45 [95% CI: 1.12-1.89]; RR = 1.65 [95% CI: 1.35-2.02], respectively; and hospitals with late onset: starting prenatal care in the third trimester (RR = 1.86 [95% CI: 1.16-2.97].CONCLUSIONS: The onset of breastfeeding is postponed, even in Baby-Friendly Hospitals, when the results of the rapid HIV test requested in the maternity are not available at the time of delivery.

  5. Survival benefit associated with adjuvant androgen deprivation therapy combined with radiotherapy for high- and low-risk patients with nonmetastatic prostate cancer

    International Nuclear Information System (INIS)

    Zeliadt, Steven B.; Potosky, Arnold L.; Penson, David F.; Etzioni, Ruth

    2006-01-01

    Background: The use of adjuvant androgen deprivation therapy (ADT) combined with radiotherapy has become common in low-risk patients, although clinical trials have focused primarily on high-risk patients. This study examines the effectiveness of adjuvant ADT combined with radiotherapy for a wide range of patients treated in the 1990s. Methods and Materials: Prostate cancer survival was examined in a population based cohort of 31,643 patients aged 65 to 85 years who were diagnosed with nonmetastatic prostate cancer and treated with external beam radiotherapy and/or brachytherapy. Instrumental variable analysis methods were used to control for selection bias. Results: Patients with stage T3/T4 disease who received adjuvant ADT experienced improved 5-year and 8-year survival. No survival advantage was observed for men with T1/T2 disease during this interval. Conclusion: High-risk patients who receive primary radiotherapy have benefited from adjuvant ADT, whereas low-risk patients with disease confined to the prostate have not yet benefited from adjuvant therapy within the first 8 years after treatment. These findings are consistent with practice guidelines, which recommend adjuvant ADT for patients with high-risk disease

  6. Acute Myeloid Leukemia: analysis of epidemiological profile and survival rate.

    Science.gov (United States)

    de Lima, Mariana Cardoso; da Silva, Denise Bousfield; Freund, Ana Paula Ferreira; Dacoregio, Juliana Shmitz; Costa, Tatiana El Jaick Bonifácio; Costa, Imaruí; Faraco, Daniel; Silva, Maurício Laerte

    2016-01-01

    To describe the epidemiological profile and the survival rate of patients with acute myeloid leukemia (AML) in a state reference pediatric hospital. Clinical-epidemiological, observational, retrospective, descriptive study. The study included new cases of patients with AML, diagnosed between 2004 and 2012, younger than 15 years. Of the 51 patients studied, 84% were white; 45% were females and 55%, males. Regarding age, 8% were younger than 1 year, 47% were aged between 1 and 10 years, and 45% were older than 10 years. The main signs/symptoms were fever (41.1%), asthenia/lack of appetite (35.2%), and hemorrhagic manifestations (27.4%). The most affected extra-medullary site was the central nervous system (14%). In 47% of patients, the white blood cell (WBC) count was below 10,000/mm(3) at diagnosis. The minimal residual disease (MRD) was less than 0.1%, on the 15th day of treatment in 16% of the sample. Medullary relapse occurred in 14% of cases. When comparing the bone marrow MRD with the vital status, it was observed that 71.42% of the patients with type M3 AML were alive, as were 54.05% of those with non-M3 AML. The death rate was 43% and the main proximate cause was septic shock (63.6%). In this study, the majority of patients were male, white, and older than 1 year. Most patients with WBC count <10,000/mm(3) at diagnosis lived. Overall survival was higher in patients with MRD <0.1%. The prognosis was better in patients with AML-M3. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  7. Parametric and semiparametric models with applications to reliability, survival analysis, and quality of life

    CERN Document Server

    Nikulin, M; Mesbah, M; Limnios, N

    2004-01-01

    Parametric and semiparametric models are tools with a wide range of applications to reliability, survival analysis, and quality of life. This self-contained volume examines these tools in survey articles written by experts currently working on the development and evaluation of models and methods. While a number of chapters deal with general theory, several explore more specific connections and recent results in "real-world" reliability theory, survival analysis, and related fields.

  8. Application of survival analysis methodology to the quantitative analysis of LC-MS proteomics data.

    Science.gov (United States)

    Tekwe, Carmen D; Carroll, Raymond J; Dabney, Alan R

    2012-08-01

    Protein abundance in quantitative proteomics is often based on observed spectral features derived from liquid chromatography mass spectrometry (LC-MS) or LC-MS/MS experiments. Peak intensities are largely non-normal in distribution. Furthermore, LC-MS-based proteomics data frequently have large proportions of missing peak intensities due to censoring mechanisms on low-abundance spectral features. Recognizing that the observed peak intensities detected with the LC-MS method are all positive, skewed and often left-censored, we propose using survival methodology to carry out differential expression analysis of proteins. Various standard statistical techniques including non-parametric tests such as the Kolmogorov-Smirnov and Wilcoxon-Mann-Whitney rank sum tests, and the parametric survival model and accelerated failure time-model with log-normal, log-logistic and Weibull distributions were used to detect any differentially expressed proteins. The statistical operating characteristics of each method are explored using both real and simulated datasets. Survival methods generally have greater statistical power than standard differential expression methods when the proportion of missing protein level data is 5% or more. In particular, the AFT models we consider consistently achieve greater statistical power than standard testing procedures, with the discrepancy widening with increasing missingness in the proportions. The testing procedures discussed in this article can all be performed using readily available software such as R. The R codes are provided as supplemental materials. ctekwe@stat.tamu.edu.

  9. Application of survival analysis methodology to the quantitative analysis of LC-MS proteomics data

    KAUST Repository

    Tekwe, C. D.

    2012-05-24

    MOTIVATION: Protein abundance in quantitative proteomics is often based on observed spectral features derived from liquid chromatography mass spectrometry (LC-MS) or LC-MS/MS experiments. Peak intensities are largely non-normal in distribution. Furthermore, LC-MS-based proteomics data frequently have large proportions of missing peak intensities due to censoring mechanisms on low-abundance spectral features. Recognizing that the observed peak intensities detected with the LC-MS method are all positive, skewed and often left-censored, we propose using survival methodology to carry out differential expression analysis of proteins. Various standard statistical techniques including non-parametric tests such as the Kolmogorov-Smirnov and Wilcoxon-Mann-Whitney rank sum tests, and the parametric survival model and accelerated failure time-model with log-normal, log-logistic and Weibull distributions were used to detect any differentially expressed proteins. The statistical operating characteristics of each method are explored using both real and simulated datasets. RESULTS: Survival methods generally have greater statistical power than standard differential expression methods when the proportion of missing protein level data is 5% or more. In particular, the AFT models we consider consistently achieve greater statistical power than standard testing procedures, with the discrepancy widening with increasing missingness in the proportions. AVAILABILITY: The testing procedures discussed in this article can all be performed using readily available software such as R. The R codes are provided as supplemental materials. CONTACT: ctekwe@stat.tamu.edu.

  10. Haptoglobin phenotype is not a predictor of recurrence free survival in high-risk primary breast cancer patients

    Directory of Open Access Journals (Sweden)

    Harris Nathan

    2008-12-01

    Full Text Available Abstract Background Better breast cancer prognostication may improve selection of patients for adjuvant therapy. We conducted a retrospective follow-up study in which we investigated sera of high-risk primary breast cancer patients, to search for proteins predictive of recurrence free survival. Methods Two sample sets of high-risk primary breast cancer patients participating in a randomised national trial investigating the effectiveness of high-dose chemotherapy were analysed. Sera in set I (n = 63 were analysed by surface enhanced laser desorption ionisation time-of-flight mass spectrometry (SELDI-TOF MS for biomarker finding. Initial results were validated by analysis of sample set II (n = 371, using one-dimensional gel-electrophoresis. Results In sample set I, the expression of a peak at mass-to-charge ratio 9198 (relative intensity ≤ 20 or > 20, identified as haptoglobin (Hp alpha-1 chain, was strongly associated with recurrence free survival (global Log-rank test; p = 0.0014. Haptoglobin is present in three distinct phenotypes (Hp 1-1, Hp 2-1, and Hp 2-2, of which only individuals with phenotype Hp 1-1 or Hp 2-1 express the haptoglobin alpha-1 chain. As the expression of the haptoglobin alpha-1 chain, determined by SELDI-TOF MS, corresponds to the phenotype, initial results were validated by haptoglobin phenotyping of the independent sample set II by native one-dimensional gel-electrophoresis. With the Hp 1-1 phenotype as the reference category, the univariate hazard ratio for recurrence was 0.87 (95% CI: 0.56 – 1.34, p = 0.5221 and 1.03 (95% CI: 0.65 – 1.64, p = 0.8966 for the Hp 2-1 and Hp 2-2 phenotypes, respectively, in sample set II. Conclusion In contrast to our initial results, the haptoglobin phenotype was not identified as a predictor of recurrence free survival in high-risk primary breast cancer in our validation set. Our initial observation in the discovery set was probably the result of a type I error (i.e. false positive

  11. Sustainable Survival for adolescents living with HIV: do SDG-aligned provisions reduce potential mortality risk?

    Science.gov (United States)

    Cluver, Lucie; Pantelic, Marija; Orkin, Mark; Toska, Elona; Medley, Sally; Sherr, Lorraine

    2018-02-01

    strongly graded reduction in potential mortality risk: Among adolescents living with HIV, potential mortality risk was 38.5% with access to no SDG-aligned provisions, and 9.3% with access to all four. SDG-aligned provisions across a range of SDGs were associated with reduced potential mortality risk among adolescents living with HIV. Access to multiple provisions has the potential to substantially improve survival, suggesting the value of connecting and combining SDGs in our response to paediatric and adolescent HIV. © 2018 The Authors. Journal of the International AIDS Society published by John Wiley & sons Ltd on behalf of the International AIDS Society.

  12. estimated glomerular filtration rate and risk of survival in acute stroke

    African Journals Online (AJOL)

    2014-03-03

    Mar 3, 2014 ... Design: A prospective observational cross-sectional study. Setting: Medical ... stroke sub-type, blood sugar, serum creatinine, serum urea and ... history of hypertension and diabetes mellitus, history of alcohol ... Declining renal function takes its toll on homeostasis .... risk of stroke: meta-analysis. BMJ 2010 ...

  13. Bruxism and dental implant failures: a multilevel mixed effects parametric survival analysis approach.

    Science.gov (United States)

    Chrcanovic, B R; Kisch, J; Albrektsson, T; Wennerberg, A

    2016-11-01

    Recent studies have suggested that the insertion of dental implants in patients being diagnosed with bruxism negatively affected the implant failure rates. The aim of the present study was to investigate the association between the bruxism and the risk of dental implant failure. This retrospective study is based on 2670 patients who received 10 096 implants at one specialist clinic. Implant- and patient-related data were collected. Descriptive statistics were used to describe the patients and implants. Multilevel mixed effects parametric survival analysis was used to test the association between bruxism and risk of implant failure adjusting for several potential confounders. Criteria from a recent international consensus (Lobbezoo et al., J Oral Rehabil, 40, 2013, 2) and from the International Classification of Sleep Disorders (International classification of sleep disorders, revised: diagnostic and coding manual, American Academy of Sleep Medicine, Chicago, 2014) were used to define and diagnose the condition. The number of implants with information available for all variables totalled 3549, placed in 994 patients, with 179 implants reported as failures. The implant failure rates were 13·0% (24/185) for bruxers and 4·6% (155/3364) for non-bruxers (P bruxism was a statistically significantly risk factor to implant failure (HR 3·396; 95% CI 1·314, 8·777; P = 0·012), as well as implant length, implant diameter, implant surface, bone quantity D in relation to quantity A, bone quality 4 in relation to quality 1 (Lekholm and Zarb classification), smoking and the intake of proton pump inhibitors. It is suggested that the bruxism may be associated with an increased risk of dental implant failure. © 2016 John Wiley & Sons Ltd.

  14. RAMS (Risk Analysis - Modular System) methodology

    Energy Technology Data Exchange (ETDEWEB)

    Stenner, R.D.; Strenge, D.L.; Buck, J.W. [and others

    1996-10-01

    The Risk Analysis - Modular System (RAMS) was developed to serve as a broad scope risk analysis tool for the Risk Assessment of the Hanford Mission (RAHM) studies. The RAHM element provides risk analysis support for Hanford Strategic Analysis and Mission Planning activities. The RAHM also provides risk analysis support for the Hanford 10-Year Plan development activities. The RAMS tool draws from a collection of specifically designed databases and modular risk analysis methodologies and models. RAMS is a flexible modular system that can be focused on targeted risk analysis needs. It is specifically designed to address risks associated with overall strategy, technical alternative, and `what if` questions regarding the Hanford cleanup mission. RAMS is set up to address both near-term and long-term risk issues. Consistency is very important for any comparative risk analysis, and RAMS is designed to efficiently and consistently compare risks and produce risk reduction estimates. There is a wide range of output information that can be generated by RAMS. These outputs can be detailed by individual contaminants, waste forms, transport pathways, exposure scenarios, individuals, populations, etc. However, they can also be in rolled-up form to support high-level strategy decisions.

  15. Analysis of survival for patients with chronic kidney disease primarily related to renal cancer surgery.

    Science.gov (United States)

    Wu, Jitao; Suk-Ouichai, Chalairat; Dong, Wen; Antonio, Elvis Caraballo; Derweesh, Ithaar H; Lane, Brian R; Demirjian, Sevag; Li, Jianbo; Campbell, Steven C

    2018-01-01

    To evaluate predictors of long-term survival for patients with chronic kidney disease primarily due to surgery (CKD-S). Patients with CKD-S have generally good survival that approximates patients who do not have CKD even after renal cancer surgery (RCS), yet there may be heterogeneity within this cohort. From 1997 to 2008, 4 246 patients underwent RCS at our centre. The median (interquartile range [IQR]) follow-up was 9.4 (7.3-11.0) years. New baseline glomerular filtration rate (GFR) was defined as highest GFR between nadir and 6 weeks after RCS. We retrospectively evaluated three cohorts: no-CKD (new baseline GFR of ≥60 mL/min/1.73 m 2 ); CKD-S (new baseline GFR of cancer-related survival (NRCRS) for the CKD-S cohort. Kaplan-Meier analysis assessed the longitudinal impact of new baseline GFR (45-60 mL/min/1.73 m 2 vs <45 mL/min/1.73 m 2 ) and Cox regression evaluated relative impact of preoperative GFR, new baseline GFR, and relevant demographics/comorbidities. Of the 4 246 patients who underwent RCS, 931 had CKD-S and 1 113 had CKD-M/S, whilst 2 202 had no-CKD even after RCS. Partial/radical nephrectomy (PN/RN) was performed in 54%/46% of the patients, respectively. For CKD-S, 641 patients had a new baseline GFR of 45-60 mL/min/1.73 m 2 and 290 had a new baseline GFR of <45 mL/min/1.73 m 2 . Kaplan-Meier analysis showed significantly reduced NRCRS for patients with CKD-S with a GFR of <45 mL/min/1.73 m 2 compared to those with no-CKD or CKD-S with a GFR of 45-60 mL/min/1.73 m 2 (both P ≤ 0.004), and competing risk analysis confirmed this (P < 0.001). Age, gender, heart disease, and new baseline GFR were all associated independently with NRCRS for patients with CKD-S (all P ≤ 0.02). Our data suggest that CKD-S is heterogeneous, and patients with a reduced new baseline GFR have compromised survival, particularly if <45 mL/min/1.73 m 2 . Our findings may have implications regarding choice of PN/RN in patients at risk of developing

  16. Neutrophil-to-lymphocyte ratio as an independent predictor for survival in patients with localized clear cell renal cell carcinoma after radiofrequency ablation: a propensity score matching analysis.

    Science.gov (United States)

    Chang, Xiaofeng; Zhang, Fan; Liu, Tieshi; Wang, Wei; Guo, Hongqian

    2017-06-01

    To investigate the role of neutrophil-to-lymphocyte ratio as a prognostic indicator in patients with localized clear cell renal cell carcinoma treated with radiofrequency ablation. We retrospectively analyzed data from patients with renal cell carcinoma who underwent radiofrequency ablation from 2006 to 2013. The Kaplan-Meier method was used to generate the survival curves according to different categories of neutrophil-to-lymphocyte ratio. Relationships between preoperative neutrophil-to-lymphocyte ratio or the change of neutrophil-to-lymphocyte ratio and survival were evaluated with multivariable Cox proportional hazards regression analysis. A propensity score matching analysis was carried out to avoid confounding bias. A total of 185 patients were included in present study. When stratified by preoperative neutrophil-to-lymphocyte ratio cutoff value of 2.79, 5-year recurrence-free survival, 5-year disease-free survival, and 5-year overall survival rates of neutrophil-to-lymphocyte ratio analysis, 5-year recurrence-free survival, 5-year disease-free survival, and 5-year overall survival rates of neutrophil-to-lymphocyte ratio ratio with the change of neutrophil-to-lymphocyte ratio, patients with both preoperative neutrophil-to-lymphocyte ratio ≥2.79 and the change of neutrophil-to-lymphocyte ratio ≥0.40 had the worst disease-free survival. Results of multivariable analysis showed that preoperative neutrophil-to-lymphocyte ratio and the change of neutrophil-to-lymphocyte ratio correlated with cancer relapse remarkably. High preoperative neutrophil-to-lymphocyte ratio and elevated postoperative neutrophil-to-lymphocyte ratio are associated with significant increase in risk of local recurrence as well as distant metastasis. The combination of neutrophil-to-lymphocyte ratio with the other prognostic indicators can be applied in the evaluation of relapse risk in patients with clear cell renal cell carcinoma after radiofrequency ablation.

  17. Multiple Gene-Environment Interactions on the Angiogenesis Gene-Pathway Impact Rectal Cancer Risk and Survival

    Directory of Open Access Journals (Sweden)

    Noha Sharafeldin

    2017-09-01

    Full Text Available Characterization of gene-environment interactions (GEIs in cancer is limited. We aimed at identifying GEIs in rectal cancer focusing on a relevant biologic process involving the angiogenesis pathway and relevant environmental exposures: cigarette smoking, alcohol consumption, and animal protein intake. We analyzed data from 747 rectal cancer cases and 956 controls from the Diet, Activity and Lifestyle as a Risk Factor for Rectal Cancer study. We applied a 3-step analysis approach: first, we searched for interactions among single nucleotide polymorphisms on the pathway genes; second, we searched for interactions among the genes, both steps using Logic regression; third, we examined the GEIs significant at the 5% level using logistic regression for cancer risk and Cox proportional hazards models for survival. Permutation-based test was used for multiple testing adjustment. We identified 8 significant GEIs associated with risk among 6 genes adjusting for multiple testing: TNF (OR = 1.85, 95% CI: 1.10, 3.11, TLR4 (OR = 2.34, 95% CI: 1.38, 3.98, and EGR2 (OR = 2.23, 95% CI: 1.04, 4.78 with smoking; IGF1R (OR = 1.69, 95% CI: 1.04, 2.72, TLR4 (OR = 2.10, 95% CI: 1.22, 3.60 and EGR2 (OR = 2.12, 95% CI: 1.01, 4.46 with alcohol; and PDGFB (OR = 1.75, 95% CI: 1.04, 2.92 and MMP1 (OR = 2.44, 95% CI: 1.24, 4.81 with protein. Five GEIs were associated with survival at the 5% significance level but not after multiple testing adjustment: CXCR1 (HR = 2.06, 95% CI: 1.13, 3.75 with smoking; and KDR (HR = 4.36, 95% CI: 1.62, 11.73, TLR2 (HR = 9.06, 95% CI: 1.14, 72.11, EGR2 (HR = 2.45, 95% CI: 1.42, 4.22, and EGFR (HR = 6.33, 95% CI: 1.95, 20.54 with protein. GEIs between angiogenesis genes and smoking, alcohol, and animal protein impact rectal cancer risk. Our results support the importance of considering the biologic hypothesis to characterize GEIs associated with cancer outcomes.

  18. Dropout during a driving simulator study: A survival analysis.

    Science.gov (United States)

    Matas, Nicole A; Nettelbeck, Ted; Burns, Nicholas R

    2015-12-01

    Simulator sickness is the occurrence of motion-sickness like symptoms that can occur during use of simulators and virtual reality technologies. This study investigated individual factors that contributed to simulator sickness and dropout while using a desktop driving simulator. Eighty-eight older adult drivers (mean age 72.82±5.42years) attempted a practice drive and two test drives. Participants also completed a battery of cognitive and visual assessments, provided information on their health and driving habits, and reported their experience of simulator sickness symptoms throughout the study. Fifty-two participants dropped out before completing the driving tasks. A time-dependent Cox Proportional Hazards model showed that female gender (HR=2.02), prior motion sickness history (HR=2.22), and Mini-SSQ score (HR=1.55) were associated with dropout. There were no differences between dropouts and completers on any of the cognitive abilities tests. Older adults are a high-risk group for simulator sickness. Within this group, female gender and prior motion sickness history are related to simulator dropout. Higher reported experience of symptoms of simulator sickness increased rates of dropout. The results highlight the importance of screening and monitoring of participants in driving simulation studies. Older adults, females, and those with a prior history of motion sickness may be especially at risk. Copyright © 2015 Elsevier Ltd and National Safety Council. All rights reserved.

  19. Streamlining project delivery through risk analysis.

    Science.gov (United States)

    2015-08-01

    Project delivery is a significant area of concern and is subject to several risks throughout Plan Development : Process (PDP). These risks are attributed to major areas of project development, such as environmental : analysis, right-of-way (ROW) acqu...

  20. KMWin--a convenient tool for graphical presentation of results from Kaplan-Meier survival time analysis.

    Science.gov (United States)

    Gross, Arnd; Ziepert, Marita; Scholz, Markus

    2012-01-01

    Analysis of clinical studies often necessitates multiple graphical representations of the results. Many professional software packages are available for this purpose. Most packages are either only commercially available or hard to use especially if one aims to generate or customize a huge number of similar graphical outputs. We developed a new, freely available software tool called KMWin (Kaplan-Meier for Windows) facilitating Kaplan-Meier survival time analysis. KMWin is based on the statistical software environment R and provides an easy to use graphical interface. Survival time data can be supplied as SPSS (sav), SAS export (xpt) or text file (dat), which is also a common export format of other applications such as Excel. Figures can directly be exported in any graphical file format supported by R. On the basis of a working example, we demonstrate how to use KMWin and present its main functions. We show how to control the interface, customize the graphical output, and analyse survival time data. A number of comparisons are performed between KMWin and SPSS regarding graphical output, statistical output, data management and development. Although the general functionality of SPSS is larger, KMWin comprises a number of features useful for survival time analysis in clinical trials and other applications. These are for example number of cases and number of cases under risk within the figure or provision of a queue system for repetitive analyses of updated data sets. Moreover, major adjustments of graphical settings can be performed easily on a single window. We conclude that our tool is well suited and convenient for repetitive analyses of survival time data. It can be used by non-statisticians and provides often used functions as well as functions which are not supplied by standard software packages. The software is routinely applied in several clinical study groups.

  1. KMWin – A Convenient Tool for Graphical Presentation of Results from Kaplan-Meier Survival Time Analysis

    Science.gov (United States)

    Gross, Arnd; Ziepert, Marita; Scholz, Markus

    2012-01-01

    Background Analysis of clinical studies often necessitates multiple graphical representations of the results. Many professional software packages are available for this purpose. Most packages are either only commercially available or hard to use especially if one aims to generate or customize a huge number of similar graphical outputs. We developed a new, freely available software tool called KMWin (Kaplan-Meier for Windows) facilitating Kaplan-Meier survival time analysis. KMWin is based on the statistical software environment R and provides an easy to use graphical interface. Survival time data can be supplied as SPSS (sav), SAS export (xpt) or text file (dat), which is also a common export format of other applications such as Excel. Figures can directly be exported in any graphical file format supported by R. Results On the basis of a working example, we demonstrate how to use KMWin and present its main functions. We show how to control the interface, customize the graphical output, and analyse survival time data. A number of comparisons are performed between KMWin and SPSS regarding graphical output, statistical output, data management and development. Although the general functionality of SPSS is larger, KMWin comprises a number of features useful for survival time analysis in clinical trials and other applications. These are for example number of cases and number of cases under risk within the figure or provision of a queue system for repetitive analyses of updated data sets. Moreover, major adjustments of graphical settings can be performed easily on a single window. Conclusions We conclude that our tool is well suited and convenient for repetitive analyses of survival time data. It can be used by non-statisticians and provides often used functions as well as functions which are not supplied by standard software packages. The software is routinely applied in several clinical study groups. PMID:22723912

  2. KMWin--a convenient tool for graphical presentation of results from Kaplan-Meier survival time analysis.

    Directory of Open Access Journals (Sweden)

    Arnd Gross

    Full Text Available BACKGROUND: Analysis of clinical studies often necessitates multiple graphical representations of the results. Many professional software packages are available for this purpose. Most packages are either only commercially available or hard to use especially if one aims to generate or customize a huge number of similar graphical outputs. We developed a new, freely available software tool called KMWin (Kaplan-Meier for Windows facilitating Kaplan-Meier survival time analysis. KMWin is based on the statistical software environment R and provides an easy to use graphical interface. Survival time data can be supplied as SPSS (sav, SAS export (xpt or text file (dat, which is also a common export format of other applications such as Excel. Figures can directly be exported in any graphical file format supported by R. RESULTS: On the basis of a working example, we demonstrate how to use KMWin and present its main functions. We show how to control the interface, customize the graphical output, and analyse survival time data. A number of comparisons are performed between KMWin and SPSS regarding graphical output, statistical output, data management and development. Although the general functionality of SPSS is larger, KMWin comprises a number of features useful for survival time analysis in clinical trials and other applications. These are for example number of cases and number of cases under risk within the figure or provision of a queue system for repetitive analyses of updated data sets. Moreover, major adjustments of graphical settings can be performed easily on a single window. CONCLUSIONS: We conclude that our tool is well suited and convenient for repetitive analyses of survival time data. It can be used by non-statisticians and provides often used functions as well as functions which are not supplied by standard software packages. The software is routinely applied in several clinical study groups.

  3. Impact of T and N substage on survival and disease relapse in adjuvant rectal cancer: a pooled analysis

    International Nuclear Information System (INIS)

    Gunderson, Leonard L.; Sargent, Daniel J.; Tepper, Joel E.; O'Connell, Michael J.; Allmer, Cristine; Smalley, Steven R.; Martenson, James A.; Haller, Daniel G.; Mayer, Robert J.; Rich, Tyvin A.; Ajani, Jaffer A.; Macdonald, John S.; Goldberg, Richard M.

    2002-01-01

    Purpose: To determine the rates of survival and disease control by TNM and MAC stage in three randomized North American rectal adjuvant studies. Materials and Methods: Data were merged from 2551 eligible patients on NCCTG 79-47-51 (n=200), NCCTG 86-47-51 (n=656), and INT 114 (n=1695). All patients received postoperative radiation, and 96% were randomized to receive concomitant and maintenance chemotherapy. Five-year follow-up was available in 94% of patients and 7-yr follow-up in 84%. Kaplan-Meier curves were used to estimate the distribution of overall survival (OS) and disease-free survival (DFS), and p values were derived using the log-rank test. Time to local and distant relapse was estimated using cumulative incidence methodology. Analyses were adjusted for treatment effect using Cox proportional hazards models. Results: OS and DFS were dependent on both TN stage and NT stage (N substage within T stage and T substage within N stage). Even among N2 patients (4 or more LN+), T stage influenced 5-yr OS (T1-2, 69%; T3, 48%; T4, 38%). Three risk groups of patients were defined: (1) intermediate: T3N0, T1-2N1; (2) moderately high: T4N0, T1-2N2, T3N1; and (3) high: T3N2, T4N1, T4N2. For Group 1, 5-yr OS was 74% and 81%, and 5-yr DFS was 66% and 74%. For Group 2, 5-yr OS ranged from 61% to 69%, and for Group 3, OS ranged from 33% to 48%. Cumulative incidence rates of local relapse and distant metastases revealed similar differences by TN and NT stage, as seen in the survival analyses. Conclusion: Patients with a single high-risk factor of either extension beyond the rectal wall (T3N0) or nodal involvement (T1-2N1) have improved OS, DFS, and disease control when compared to those with both high risk factors. Different treatment strategies may be indicated for intermediate- (T3N0, T1-2N1) vs. moderately high or high-risk patients in view of differential survival and rates of relapse. For future trial design, it may be preferable to perform separate studies, or a planned

  4. Survival Analysis of US Air Force Officer Retention Rate

    Science.gov (United States)

    2017-03-23

    an independent global business research organization] has studied the timing of unemployment… the timing of this variable is designated as...retrieval, and management; report writing and graphics design; statistical and mathematical analysis; business forecasting and decision support; operations...less flexible to experimentation with the system’s variables and assumptions. Today , many researchers utilize simulation to model real world

  5. A Benefit-Risk Analysis Approach to Capture Regulatory Decision-Making: Multiple Myeloma.

    Science.gov (United States)

    Raju, G K; Gurumurthi, Karthik; Domike, Reuben; Kazandjian, Dickran; Landgren, Ola; Blumenthal, Gideon M; Farrell, Ann; Pazdur, Richard; Woodcock, Janet

    2018-01-01

    Drug regulators around the world make decisions about drug approvability based on qualitative benefit-risk analysis. In this work, a quantitative benefit-risk analysis approach captures regulatory decision-making about new drugs to treat multiple myeloma (MM). MM assessments have been based on endpoints such as time to progression (TTP), progression-free survival (PFS), and objective response rate (ORR) which are different than benefit-risk analysis based on overall survival (OS). Twenty-three FDA decisions on MM drugs submitted to FDA between 2003 and 2016 were identified and analyzed. The benefits and risks were quantified relative to comparators (typically the control arm of the clinical trial) to estimate whether the median benefit-risk was positive or negative. A sensitivity analysis was demonstrated using ixazomib to explore the magnitude of uncertainty. FDA approval decision outcomes were consistent and logical using this benefit-risk framework. © 2017 American Society for Clinical Pharmacology and Therapeutics.

  6. Marital status and survival in patients with rectal cancer: An analysis of the Surveillance, Epidemiology and End Results (SEER) database.

    Science.gov (United States)

    Wang, Xiangyang; Cao, Weilan; Zheng, Chenguo; Hu, Wanle; Liu, Changbao

    2018-06-01

    Marital status has been validated as an independent prognostic factor for survival in several cancer types, but is controversial in rectal cancer (RC). The objective of this study was to investigate the impact of marital status on the survival outcomes of patients with RC. We extracted data of 27,498 eligible patients diagnosed with RC between 2004 and 2009 from the Surveillance, Epidemiology and End Results (SEER) database. Patients were categorized into married, never married, divorced/separated and widowed groups.We used Chi-square tests to compare characteristics of patients with different marital status.Rectal cancer specific survival was compared using the Kaplan-Meier method,and multivariate Cox regression analyses was used to analyze the survival outcome risk factors in different marital status. The widowed group had the highest percentage of elderly patients and women,higher proportion of adenocarcinomas, and more stage I/II in tumor stage (P married group (76.7% VS 85.4%). Compared with the married patients, the never married (HR 1.40), widowed (HR 1.61,) and divorced/separated patients (HR 1.16) had an increased overall 5-year mortality. A further analysis showed that widowed patients had an increased overall 5-year cause-specific survival(CSS) compared with married patients at stage I(HR 1.92),stage II (HR 1.65),stage III (HR 1.73),and stage IV (HR 1.38). Our study showed marriage was associated with better outcomes of RC patients, but unmarried RC patients, especially widowed patients,are at greater risk of cancer specific mortality. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Effects of maternal nutrition, resource use and multi-predator risk on neonatal white-tailed deer survival.

    Directory of Open Access Journals (Sweden)

    Jared F Duquette

    Full Text Available Growth of ungulate populations is typically most sensitive to survival of neonates, which in turn is influenced by maternal nutritional condition and trade-offs in resource selection and avoidance of predators. We assessed whether resource use, multi-predator risk, maternal nutritional effects, hiding cover, or interactions among these variables best explained variation in daily survival of free-ranging neonatal white-tailed deer (Odocoileus virginianus during their post-partum period (14 May-31 Aug in Michigan, USA. We used Cox proportional hazards mixed-effects models to assess survival related to covariates of resource use, composite predation risk of 4 mammalian predators, fawn body mass at birth, winter weather, and vegetation growth phenology. Predation, particularly from coyotes (Canis latrans, was the leading cause of mortality; however, an additive model of non-ideal resource use and maternal nutritional effects explained 71% of the variation in survival. This relationship suggested that dams selected areas where fawns had poor resources, while greater predation in these areas led to additive mortalities beyond those related to resource use alone. Also, maternal nutritional effects suggested that severe winters resulted in dams producing smaller fawns, which decreased their likelihood of survival. Fawn resource use appeared to reflect dam avoidance of lowland forests with poor forage and greater use by wolves (C. lupus, their primary predator. While this strategy led to greater fawn mortality, particularly by coyotes, it likely promoted the life-long reproductive success of dams because many reached late-age (>10 years old and could have produced multiple generations of fawns. Studies often link resource selection and survival of ungulates, but our results suggested that multiple factors can mediate that relationship, including multi-predator risk. We emphasize the importance of identifying interactions among biological and

  8. Survival after Second and Subsequent Recurrences in Osteosarcoma: A Retrospective Multicenter Analysis.

    Science.gov (United States)

    Tirtei, Elisa; Asaftei, Sebastian D; Manicone, Rosaria; Cesari, Marilena; Paioli, Anna; Rocca, Michele; Ferrari, Stefano; Fagioli, Franca

    2017-05-01

    Purpose Osteosarcoma (OS) is the most common primary bone tumor. Despite complete surgical removal and intensive chemotherapeutic treatment, 30%-35% of patients with OS have local or systemic recurrence. Some patients survive multiple recurrences, but overall survival after OS recurrence is poor. This analysis aims to describe and identify factors influencing post-relapse survival (PRS) after a second OS relapse. Methods This is a retrospective analysis of 60 patients with a second relapse of OS of the extremities in 2 Italian centers between 2003 and 2013. Results Treatment for first and subsequent relapses was planned according to institutional guidelines. After complete surgical remission (CSR) following the first recurrence, patients experienced a second OS relapse with a median disease-free interval (DFI) of 6 months. Lung disease was prevalent: 44 patients (76%) had pulmonary metastases. Survival after the second relapse was 22% at 5 years. Lung disease only correlated with better survival at 5 years (33.6%) compared with other sites of recurrence (5%; p = 0.008). Patients with a single pulmonary lesion had a better 5-year second PRS (42%; p = 0.02). Patients who achieved a second CSR had a 5-year second PRS of 33.4%. Chemotherapy (p<0.001) benefited patients without a third CSR. Conclusions This analysis confirms the importance of an aggressive, repeated surgical approach. Lung metastases only, the number of lesions, DFI and CSR influenced survival. It also confirms the importance of chemotherapy in patients in whom surgical treatment is not feasible.

  9. Vitamin C and survival among women with breast cancer: a meta-analysis.

    Science.gov (United States)

    Harris, Holly R; Orsini, Nicola; Wolk, Alicja

    2014-05-01

    The association between dietary vitamin C intake and breast cancer survival is inconsistent and few studies have specifically examined vitamin C supplement use among women with breast cancer. The purpose of this study was to summarise results from prospective studies on the association between vitamin C supplement use and dietary vitamin C intake and breast cancer-specific mortality and total mortality. Studies were identified using the PubMed database through February 6, 2014 and by examining the references of retrieved articles. Prospective studies were included if they reported relative risks (RR) with 95% confidence intervals (95% CIs) for at least two categories or as a continuous exposure. Random-effects models were used to combine study-specific results. The ten identified studies examined vitamin C supplement use (n=6) and dietary vitamin C intake (n=7) and included 17,696 breast cancer cases, 2791 total deaths, and 1558 breast cancer-specific deaths. The summary RR (95% CI) for post-diagnosis vitamin C supplement use was 0.81 (95% CI 0.72-0.91) for total mortality and 0.85 (95% CI 0.74-0.99) for breast cancer-specific mortality. The summary RR for a 100mg per day increase in dietary vitamin C intake was 0.73 (95% CI 0.59-0.89) for total mortality and 0.78 (95% CI 0.64-0.94) for breast cancer-specific mortality. Results from this meta-analysis suggest that post-diagnosis vitamin C supplement use may be associated with a reduced risk of mortality. Dietary vitamin C intake was also statistically significantly associated with a reduced risk of total mortality and breast cancer-specific mortality. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Analysis of single nucleotide variants of HFE gene and association to survival in The Cancer Genome Atlas GBM data.

    Science.gov (United States)

    Lee, Sang Y; Zhu, Junjia; Salzberg, Anna C; Zhang, Bo; Liu, Dajiang J; Muscat, Joshua E; Langan, Sara T; Connor, James R

    2017-01-01

    Human hemochromatosis protein (HFE) is involved in iron metabolism. Two major HFE polymorphisms, H63D and C282Y, have been associated with an increased risk of cancers. Previously, we reported decreased gender effects in overall survival based on H63D or C282Y HFE polymorphisms patients with glioblastoma multiforme (GBM). However, the effect of other single nucleotide variation (SNV) in the HFE gene on the cancer development and progression has not been systematically studied. To expand our finding in a larger sample, and to identify other HFE SNV, we analyzed the frequency of somatic SNV in HFE gene and its relationship to survival in GBM patients using The Cancer Genome Atlas (TCGA) GBM (Caucasian only) database. We found 9 SNVs with increased frequency in blood normal of TCGA GBM patients compared to the 1000Genome. Among 9 SNVs, 7 SNVs were located in the intron and 2 SNVs (i.e., H63D, C282Y) in the exon of HFE gene. The statistical analysis demonstrated that blood normal samples of TCGA GBM have more H63D (p = 0.0002, 95% Confidence interval (CI): 0.2119-0.3223) or C282Y (p = 0.0129, 95% CI: 0.0474-0.1159) HFE polymorphisms than 1000Genome. The Kaplan-Meier survival curve for the 264 GBM samples revealed no difference between wild type (WT) HFE and H63D, and WT HFE and C282Y GBM patients. In addition, there was no difference in the survival of male/female GBM patients based on HFE genotype. There was no correlation between HFE expression and survival. In conclusion, the current results suggest that somatic HFE polymorphisms do not impact GBM patients' survival in the TCGA data set of GBM.

  11. Analysis of single nucleotide variants of HFE gene and association to survival in The Cancer Genome Atlas GBM data.

    Directory of Open Access Journals (Sweden)

    Sang Y Lee

    Full Text Available Human hemochromatosis protein (HFE is involved in iron metabolism. Two major HFE polymorphisms, H63D and C282Y, have been associated with an increased risk of cancers. Previously, we reported decreased gender effects in overall survival based on H63D or C282Y HFE polymorphisms patients with glioblastoma multiforme (GBM. However, the effect of other single nucleotide variation (SNV in the HFE gene on the cancer development and progression has not been systematically studied. To expand our finding in a larger sample, and to identify other HFE SNV, we analyzed the frequency of somatic SNV in HFE gene and its relationship to survival in GBM patients using The Cancer Genome Atlas (TCGA GBM (Caucasian only database. We found 9 SNVs with increased frequency in blood normal of TCGA GBM patients compared to the 1000Genome. Among 9 SNVs, 7 SNVs were located in the intron and 2 SNVs (i.e., H63D, C282Y in the exon of HFE gene. The statistical analysis demonstrated that blood normal samples of TCGA GBM have more H63D (p = 0.0002, 95% Confidence interval (CI: 0.2119-0.3223 or C282Y (p = 0.0129, 95% CI: 0.0474-0.1159 HFE polymorphisms than 1000Genome. The Kaplan-Meier survival curve for the 264 GBM samples revealed no difference between wild type (WT HFE and H63D, and WT HFE and C282Y GBM patients. In addition, there was no difference in the survival of male/female GBM patients based on HFE genotype. There was no correlation between HFE expression and survival. In conclusion, the current results suggest that somatic HFE polymorphisms do not impact GBM patients' survival in the TCGA data set of GBM.

  12. Mediation analysis of the relationship between institutional research activity and patient survival

    DEFF Research Database (Denmark)

    Rochon, Justine; du Bois, Andreas; Lange, Theis

    2014-01-01

    BACKGROUND: Recent studies have suggested that patients treated in research-active institutions have better outcomes than patients treated in research-inactive institutions. However, little attention has been paid to explaining such effects, probably because techniques for mediation analysis...... existing so far have not been applicable to survival data. METHODS: We investigated the underlying mechanisms using a recently developed method for mediation analysis of survival data. Our analysis of the effect of research activity on patient survival was based on 352 patients who had been diagnosed...... mediated through either optimal surgery or chemotherapy. Taken together, about 26% of the beneficial effect of research activity was mediated through the proposed pathways. CONCLUSIONS: Mediation analysis allows proceeding from the question "Does it work?" to the question "How does it work?" In particular...

  13. 10-Year Survival and Quality of Life in Patients With High-Risk PN0 Prostate Cancer Following Definitive Radiotherapy

    International Nuclear Information System (INIS)

    Berg, Arne; Lilleby, Wolfgang; Bruland, Oyvind Sverre; Fossa, Sophie Dorothea

    2007-01-01

    Purpose: To evaluate long-term overall survival (OS), cancer-specific survival (CSS), clinical progression-free survival (cPFS), and health-related quality of life (HRQoL) following definitive radiotherapy (RT) given to T 1-4p N 0 M 0 prostate cancer patients provided by a single institution between 1989 and 1996. Methods and Materials: We assessed outcome among 203 patients who had completed three-dimensional conformal RT (66 Gy) without hormone treatment and in whom staging by lymphadenectomy had been performed. OS was compared with an age-matched control group from the general population. A cross-sectional, self-report survey of HRQoL was performed among surviving patients. Results: Median observation time was 10 years (range, 1-16 years). Eighty-one percent had high-risk tumors defined as T 3-4 or Gleason score (GS) ≥7B (4+3). Among these, 10-year OS, CSS, and cPFS rates were 52%, 66%, and 39%, respectively. The corresponding fractions in low-risk patients (T 1-2 and GS ≤7A [3+4]) were 79%, 95%, and 73%, respectively. Both CSS and cPFS were predicted by GS and T-classification; OS was associated with GS only. High-risk, but not low-risk, patients had reduced OS compared with the general population (p p N 0 , RT with dosage 3-4 or GS ≥7B

  14. Improved survival and renal prognosis of patients with type 2 diabetes and nephropathy with improved control of risk factors

    DEFF Research Database (Denmark)

    Andrésdóttir, Gudbjörg; Jensen, Majken; Carstensen, Bendix

    2014-01-01

    OBJECTIVE: To evaluate long-term survival, development of renal end points, and decline in glomerular filtration rate (GFR) in patients with type 2 diabetes and diabetic nephropathy (DN) after renin-angiotensin system (RAS) inhibition and multifactorial treatment of cardiovascular risk factors ha...

  15. Frontline low-dose alemtuzumab with fludarabine and cyclophosphamide prolongs progression-free survival in high-risk CLL

    DEFF Research Database (Denmark)

    Geisler, Christian H; van T' Veer, Mars B; Jurlander, Jesper

    2014-01-01

    .3%). FCA improves progression-free survival in high-risk chronic lymphocytic leukemia. As anticipated, FCA is more immunosuppressive than FC, but with due vigilance, does not lead to a higher treatment-related mortality. This study was registered at www.trialregister.nl as trial no. NTR529....

  16. Haptoglobin phenotype is not a predictor of recurrence free survival in high-risk primary breast cancer patients

    NARCIS (Netherlands)

    Gast, M.C.; van Tinteren, H.; Bontenbal, M.; van Hoesel, R.Q.; Nooij, M.A.; Rodenhuis, S.; Span, P.N.; Tjan-Heijnen, V.C.; de Vries, E.G.; Harris, N.; Twisk, J.W.R.; Schellens, J.H.; Beijnen, J.H.

    2008-01-01

    Background: Better breast cancer prognostication may improve selection of patients for adjuvant therapy. We conducted a retrospective follow-up study in which we investigated sera of high-risk primary breast cancer patients, to search for proteins predictive of recurrence free survival. Methods: Two

  17. Haptoglobin phenotype is not a predictor of recurrence free survival in high-risk primary breast cancer patients

    NARCIS (Netherlands)

    M.C.W. Gast; H. van Tinteren (Harm); M. Bontenbal (Marijke); R.Q.G.C.M. van Hoesel (René); M.A. Nooij; S. Rodenhuis (Sjoerd); P.N. Span (Paul); V.C.G. Tjan-Heijnen (Vivianne); E. de Vries (Esther); N. Harris (Nathan); J.W.R. Twisk (Jos); J.H.M. Schellens (Jan); J.H. Beijnen (Jos)

    2008-01-01

    textabstractBackground: Better breast cancer prognostication may improve selection of patients for adjuvant therapy. We conducted a retrospective follow-up study in which we investigated sera of high-risk primary breast cancer patients, to search for proteins predictive of recurrence free survival.

  18. Haptoglobin phenotype is not a predictor of recurrence free survival in high-risk primary breast cancer patients

    NARCIS (Netherlands)

    Gast, Marie-Christine W.; van Tinteren, Harm; Bontenbal, Marijke; van Hoesel, Rene Q. G. C. M.; Nooij, Marianne A.; Rodenhuis, Sjoerd; Span, Paul N.; Tjan-Heijnen, Vivianne C. G.; de Vries, Elisabeth G. E.; Harris, Nathan; Twisk, Jos W. R.; Schellens, Jan H. M.; Beijnen, Jos H.

    2008-01-01

    ABSTRACT: BACKGROUND: Better breast cancer prognostication may improve selection of patients for adjuvant therapy. We conducted a retrospective follow-up study in which we investigated sera of high-risk primary breast cancer patients, to search for proteins predictive of recurrence free survival.

  19. Haptoglobin phenotype is not a predictor of recurrence free survival in high-risk primary breast cancer patients.

    NARCIS (Netherlands)

    Gast, M.C.; Tinteren, H. van; Bontenbal, M.; Hoesel, R.Q. van; Nooij, M.A.; Rodenhuis, S.; Span, P.N.; Tjan-Heijnen, V.C.; Vries, E.G.F. de; Harris, N.; Twisk, J.W.R.; Schellens, J.H.; Beijnen, J.H.

    2008-01-01

    BACKGROUND: Better breast cancer prognostication may improve selection of patients for adjuvant therapy. We conducted a retrospective follow-up study in which we investigated sera of high-risk primary breast cancer patients, to search for proteins predictive of recurrence free survival. METHODS: Two

  20. Predicting long-term risk for relationship dissolution using nonparametric conditional survival trees.

    Science.gov (United States)

    Kliem, Sören; Weusthoff, Sarah; Hahlweg, Kurt; Baucom, Katherine J W; Baucom, Brian R

    2015-12-01

    Identifying risk factors for divorce or separation is an important step in the prevention of negative individual outcomes and societal costs associated with relationship dissolution. Programs that aim to prevent relationship distress and dissolution typically focus on changing processes that occur during couple conflict, although the predictive ability of conflict-specific variables has not been examined in the context of other factors related to relationship dissolution. The authors examine whether emotional responding and communication during couple conflict predict relationship dissolution after controlling for overall relationship quality and individual well-being. Using nonparametric conditional survival trees, the study at hand simultaneously examined the predictive abilities of physiological (systolic and diastolic blood pressure, heart rate, cortisol) and behavioral (fundamental frequency; f0) indices of emotional responding, as well as observationally coded positive and negative communication behavior, on long-term relationship stability after controlling for relationship satisfaction and symptoms of depression. One hundred thirty-six spouses were assessed after participating in a randomized clinical trial of a relationship distress prevention program as well as 11 years thereafter; 32.5% of the couples' relationships had dissolved by follow up. For men, the only significant predictor of relationship dissolution was cortisol change score (p = .012). For women, only f0 range was a significant predictor of relationship dissolution (p = .034). These findings highlight the importance of emotional responding during couple conflict for long-term relationship stability. (c) 2015 APA, all rights reserved).

  1. Adoption of new drugs by physicians: a survival analysis

    Directory of Open Access Journals (Sweden)

    Garjón Francisco

    2012-03-01

    Full Text Available Abstract Background New drugs often substitute others cheaper and with a risk-benefit balance better established. Our aim was to analyse the diffusion of new drugs during the first months of use, examining the differences between family physicians and specialists. Methods Prescription data were obtained of cefditoren, duloxetine, etoricoxib, ezetimibe, levocetirizine, olmesartan, pregabalin and tiotropium 36 months after their launching. We obtained the monthly number of prescriptions per doctor and the number prescribers of each drug by specialty. After discarding those with less than 10 prescriptions during this period, physicians were defined as adopters if the number of prescriptions was over the 25th percentile for each drug and level (primary or secondary care. The diffusion of each drug was studied by determining the number of adopter family physicians throughout the study period. Among the group of adopters, we compared the month of the first prescription by family physicians to that of other specialists using the Kaplan-Meier method. Results The adoption of the drugs in primary care follows an exponential diffusion curve that reaches a plateau at month 6 to 23. Tiotropium was the most rapidly and widely adopted drug. Cefditoren spread at a slower rate and was the least adopted. The diffusion of etoricoxib was initially slowed down due to administrative requirements for its prescription. The median time of adoption in the case of family physicians was 4-6 months. For each of the drugs, physicians of a specialty other than family physicians adopted it first. Conclusions The number of adopters of a new drug increases quickly in the first months and reaches a plateau. The number of adopter family physicians varies considerably for different drugs. The adoption of new drugs is faster in specialists. The time of adoption should be considered to promote rational prescribing by providing timely information about new drugs and independent

  2. Community-Based Management of Child Malnutrition in Zambia: HIV/AIDS Infection and Other Risk Factors on Child Survival

    Directory of Open Access Journals (Sweden)

    Stefania Moramarco

    2016-07-01

    Full Text Available (1 Background: Supplementary feeding programs (SFPs are effective in the community-based treatment of moderate acute malnutrition (MAM and prevention of severe acute malnutrition (SAM; (2 Methods: A retrospective study was conducted on a sample of 1266 Zambian malnourished children assisted from 2012 to 2014 in the Rainbow Project SFPs. Nutritional status was evaluated according to WHO/Unicef methodology. We performed univariate and multivariate Cox proportional risk regression to identify the main predictors of mortality. In addition, a time-to event analysis was performed to identify predictors of failure and time to cure events; (3 Results: The analysis included 858 malnourished children (19 months ± 9.4; 49.9% males. Program outcomes met international standards with a better performance for MAM compared to SAM. Cox regression identified SAM (3.8; 2.1–6.8, HIV infection (3.1; 1.7–5.5, and WAZ <−3 (3.1; 1.6–5.7 as predictors of death. Time to event showed 80% of children recovered by SAM/MAM at 24 weeks. (4 Conclusions: Preventing deterioration of malnutrition, coupled to early detection of HIV/AIDS with adequate antiretroviral treatment, and extending the duration of feeding supplementation, could be crucial elements for ensuring full recovery and improve child survival in malnourished Zambian children.

  3. Community-Based Management of Child Malnutrition in Zambia: HIV/AIDS Infection and Other Risk Factors on Child Survival.

    Science.gov (United States)

    Moramarco, Stefania; Amerio, Giulia; Ciarlantini, Clarice; Chipoma, Jean Kasengele; Simpungwe, Matilda Kakungu; Nielsen-Saines, Karin; Palombi, Leonardo; Buonomo, Ersilia

    2016-07-01

    (1) BACKGROUND: Supplementary feeding programs (SFPs) are effective in the community-based treatment of moderate acute malnutrition (MAM) and prevention of severe acute malnutrition (SAM); (2) METHODS: A retrospective study was conducted on a sample of 1266 Zambian malnourished children assisted from 2012 to 2014 in the Rainbow Project SFPs. Nutritional status was evaluated according to WHO/Unicef methodology. We performed univariate and multivariate Cox proportional risk regression to identify the main predictors of mortality. In addition, a time-to event analysis was performed to identify predictors of failure and time to cure events; (3) RESULTS: The analysis included 858 malnourished children (19 months ± 9.4; 49.9% males). Program outcomes met international standards with a better performance for MAM compared to SAM. Cox regression identified SAM (3.8; 2.1-6.8), HIV infection (3.1; 1.7-5.5), and WAZ malnutrition, coupled to early detection of HIV/AIDS with adequate antiretroviral treatment, and extending the duration of feeding supplementation, could be crucial elements for ensuring full recovery and improve child survival in malnourished Zambian children.

  4. Pregnancy associated nasopharyngeal carcinoma: A retrospective case-control analysis of maternal survival outcomes

    International Nuclear Information System (INIS)

    Cheng, Yi-Kan; Zhang, Fan; Tang, Ling-Long; Chen, Lei; Zhou, Guan-Qun; Zeng, Mu-Sheng; Kang, Tie-Bang; Jia, Wei-Hua; Shao, Jian-Yong; Mai, Hai-Qiang; Guo, Ying; Ma, Jun

    2015-01-01

    Background: Pregnancy-associated nasopharyngeal carcinoma (PANPC) has been associated with poor survival. Recent advances in radiation technology and imaging techniques, and the introduction of chemotherapy have improved survival in nasopharyngeal carcinoma (NPC); however, it is not clear whether these changes have improved survival in PANPC. Therefore, the purpose of this study was to compare five-year maternal survival in patients with PANPC and non-pregnant patients with NPC. Methods: After adjusting for age, stage and chemotherapy mode, we conducted a retrospective case-control study among 36 non-metastatic PANPC patients and 36 non-pregnant NPC patients (control group) who were treated at our institution between 2000 and 2010. Results: The median age of both groups was 30 years (range, 23–35 years); median follow-up for all patients was 70 months. Locoregionally-advanced disease accounted for 83.3% of all patients with PANPC and 92.9% of patients who developed NPC during pregnancy. In both the PANPC and control groups, 31 patients (86.1%) received chemotherapy and all patients received definitive radiotherapy. The five-year rates for overall survival (70% vs. 78%, p = 0.72), distant metastasis-free survival (79% vs. 76%, p = 0.77), loco-regional relapse-free survival (97% vs. 91%, p = 0.69) and disease-free survival (69% vs. 74%, p = 0.98) were not significantly different between the PANPC and control groups. Multivariate analysis using a Cox proportional hazards model revealed that only N-classification was significantly associated with five-year OS. Conclusion: This study demonstrates that, in the modern treatment era, pregnancy itself may not negatively influence survival outcomes in patients with NPC; however, pregnancy may delay the diagnosis of NPC

  5. Risk analysis and safety rationale

    International Nuclear Information System (INIS)

    Bengtsson, G.

    1989-01-01

    Decision making with respect to safety is becoming more and more complex. The risk involved must be taken into account together with numerous other factors such as the benefits, the uncertainties and the public perception. Can the decision maker be aided by some kind of system, general rules of thumb, or broader perspective on similar decisions? This question has been addressed in a joint Nordic project relating to nuclear power. Modern techniques for risk assessment and management have been studied, and parallels drawn to such areas as offshore safety and management of toxic chemicals in the environment. The report summarises the finding of 5 major technical reports which have been published in the NORD-series. The topics includes developments, uncertainties and limitations in probabilistic safety assessments, negligible risks, risk-cost trade-offs, optimisation of nuclear safety and radiation protection, and the role of risks in the decision making process. (author) 84 refs

  6. Survival Analysis and its Associated Factors of Beta Thalassemia Major in Hamadan Province

    Directory of Open Access Journals (Sweden)

    Reza Zamani

    2015-05-01

    Full Text Available Background: There currently is a lack of knowledge about the long-term survival of patients with beta thalassemia (BT, particularly in regions with low incidence of the disease. The aim of the present study was to determine the survival rate of the patients with BT major and the factors associated with the survival time. Methods: This retrospective cohort study was performed in Hamadan province, located in the west of Iran. The study included patients that referred to the provincial hospitals during 16 year period from 1997 to 2013. The follow up of each subject was calculated from the date of birth to the date of death. Demographic and clinical data were extracted from patients’ medical records using a checklist. Statistical analysis included the Kaplan-Meier method to analyze survivals, log-rank to compare curves between groups, and Cox regression for multivariate prognostic analysis. Results: A total of 133 patients with BT major were enrolled, 54.9% of whom were male and 66.2% were urban. The 10-, 20- and 30-year survival rate for all patients were 98.3%, 88.4% and 80.5%, respectively. Based on hazard ratio (HR, we found that accompanied diseases (P=0.01, blood type (P=0.03 and residency status (P=0.01 were significant predictors for the survival time of patients. Conclusion: The survival rate of BT patients has improved. Future researches such as prospective designs are required for the estimation of survival rate and to find other prognostic factors, which have reliable sources of data.

  7. A background to risk analysis. Vol. 2

    International Nuclear Information System (INIS)

    Taylor, J.R.

    1979-01-01

    This 4-volumes report gives a background of ideas, principles and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques described are somewhat experimental. The report is written in an introductory style, but where some point needs further justification or evaluation, this is given in the form of a chapter appendix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 2 treats generic methods of qualitative failure analysis. (BP)

  8. The EPOS-CC Score: An Integration of Independent, Tumor- and Patient-Associated Risk Factors to Predict 5-years Overall Survival Following Colorectal Cancer Surgery.

    Science.gov (United States)

    Haga, Yoshio; Ikejiri, Koji; Wada, Yasuo; Ikenaga, Masakazu; Koike, Shoichiro; Nakamura, Seiji; Koseki, Masato

    2015-06-01

    Surgical audit is an essential task for the estimation of postoperative outcome and comparison of quality of care. Previous studies on surgical audits focused on short-term outcomes, such as postoperative mortality. We propose a surgical audit evaluating long-term outcome following colorectal cancer surgery. The predictive model for this audit is designated as 'Estimation of Postoperative Overall Survival for Colorectal Cancer (EPOS-CC)'. Thirty-one tumor-related and physiological variables were prospectively collected in 889 patients undergoing elective resection for colorectal cancer between April 2005 and April 2007 in 16 Japanese hospitals. Postoperative overall survival was assessed over a 5-years period. The EPOS-CC score was established by selecting significant variables in a uni- and multivariate analysis and allocating a risk-adjusted multiplication factor to each variable using Cox regression analysis. For validation, the EPOS-CC score was compared to the predictive power of UICC stage. Inter-hospital variability of the observed-to-estimated 5-years survival was assessed to estimate quality of care. Among the 889 patients, 804 (90%) completed the 5-years follow-up. Univariate analysis displayed a significant correlation with 5-years survival for 14 physiological and nine tumor-related variables (p model for the prediction of survival. Risk-adjusted multiplication factors between 1.5 (distant metastasis) and 0.16 (serum sodium level) were accorded to the different variables. The predictive power of EPOS-CC was superior to the one of UICC stage; area under the curve 0.87, 95% CI 0.85-0.90 for EPOS-CC, and 0.80, 0.76-0.83 for UICC stage, p < 0.001. Quality of care did not differ between hospitals. The EPOS-CC score including the independent variables age, performance status, serum sodium level, TNM stage, and lymphatic invasion is superior to the UICC stage in the prediction of 5-years overall survival. This higher accuracy might be explained by the

  9. Risk Analysis of Telecom Enterprise Financing

    Institute of Scientific and Technical Information of China (English)

    YU Hua; SHU Hua-ying

    2005-01-01

    The main research objects in this paper are the causes searching and risk estimating method for telecom enterprises' financial risks. The multi-mode financing for telecom enterprises makes it flexible to induce the capital and obtain the profit by corresponding projects. But there are also potential risks going with these financing modes. After making analysis of categories and causes of telecom enterprises' financing risk, a method by Analytic Hierarchy Process (AHP) is put forward to estimating the financing risk. And the author makes her suggestion and opinion by example analysis, in order to provide some ideas and basis for telecom enterprise's financing decision-making.

  10. Absence of survival benefit of radioactive iodine (RAI) after thyroidectomy in low risk differentiated thyroid cancer (DTC) patients

    International Nuclear Information System (INIS)

    Schwartz, C.; Fieffe, S.; Pochart, J.M.; Bonnetain, F.; Gauthier, M.; Cueff, A.; Crevisy, E.; Dygai-Cochet, I.; Toubeau, M.

    2012-01-01

    After thyroidectomy, the goal of the first dose of radioactive iodine (RAI) is remnant ablation to facilitate the initial staging with the post-therapy scan and to facilitate the early detection of recurrences. The purpose of this study is to the survival benefit of RAI in low-risk thyroid cancer patients. Using Cancer thyroid registry of Marne Ardennes (1041 patients) and hospital data base of centre Leclerc (257 patients), we included all differentiated thyroid cancer (DTC) patients at low risk from 1975 to 2005. Median follow-up was 10.3 years, during which 19 recurrences, 61 other malignant diseases and 105 deaths were registered. 387 patients (30%) received no RAI and 911 had RAI (70%). If we confirmed that some clinical characteristics were associated with RAI intake, the study failed to demonstrate any survival benefit of RAI in low risk DTC patients

  11. Absence of survival benefit of radioactive iodine (RAI) after thyroidectomy in low risk differentiated thyroid cancer (DTC) patients

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, C.; Fieffe, S.; Pochart, J.M. [Endocrinology Nuclear Medicine, Institut Jean Godinot, Reims (France); Bonnetain, F.; Gauthier, M.; Cueff, A. [Statistics and Epidemiology, Centre Georges Francois Leclerc, Dijon (France); Crevisy, E.; Dygai-Cochet, I.; Toubeau, M. [Nuclear Medicine, Centre Georges Francois Leclerc, Dijon (France)

    2012-07-01

    After thyroidectomy, the goal of the first dose of radioactive iodine (RAI) is remnant ablation to facilitate the initial staging with the post-therapy scan and to facilitate the early detection of recurrences. The purpose of this study is to the survival benefit of RAI in low-risk thyroid cancer patients. Using Cancer thyroid registry of Marne Ardennes (1041 patients) and hospital data base of centre Leclerc (257 patients), we included all differentiated thyroid cancer (DTC) patients at low risk from 1975 to 2005. Median follow-up was 10.3 years, during which 19 recurrences, 61 other malignant diseases and 105 deaths were registered. 387 patients (30%) received no RAI and 911 had RAI (70%). If we confirmed that some clinical characteristics were associated with RAI intake, the study failed to demonstrate any survival benefit of RAI in low risk DTC patients

  12. Systemic meningococcal disease in children: survival analysis, Arkhangelsk region, Northwest Russia, 1991–2011

    Directory of Open Access Journals (Sweden)

    O. V. Samodova

    2012-01-01

    Full Text Available Systemic meningococcal infection requires prompt and adequate medical care. It is considered as unpredictable disease due to extreme severity of a patient’s condition and high risk for fatal outcome. Survival of the children with systemic meningococcal infection was studied. Retrospective cohort includes all cases of systemic meningococcal disease in children arose in Arkhangelsk region in 1991–2011. Rate of fatal outcomes was high (41%. All death cases occurred during first three days of illness. Survival of the patient with correct pre-admission diagnosis was higher in comparison with initially undiagnosed cases. Survival functions were influenced by form of the disease and presence of septic shock. The usage of intramuscular injection of glucocorticoids on pre-admission stage according to the common recommendations did not improve the outcome.

  13. Bayesian linear regression with skew-symmetric error distributions with applications to survival analysis

    KAUST Repository

    Rubio, Francisco J.

    2016-02-09

    We study Bayesian linear regression models with skew-symmetric scale mixtures of normal error distributions. These kinds of models can be used to capture departures from the usual assumption of normality of the errors in terms of heavy tails and asymmetry. We propose a general noninformative prior structure for these regression models and show that the corresponding posterior distribution is proper under mild conditions. We extend these propriety results to cases where the response variables are censored. The latter scenario is of interest in the context of accelerated failure time models, which are relevant in survival analysis. We present a simulation study that demonstrates good frequentist properties of the posterior credible intervals associated with the proposed priors. This study also sheds some light on the trade-off between increased model flexibility and the risk of over-fitting. We illustrate the performance of the proposed models with real data. Although we focus on models with univariate response variables, we also present some extensions to the multivariate case in the Supporting Information.

  14. PRA and Risk Informed Analysis

    International Nuclear Information System (INIS)

    Bernsen, Sidney A.; Simonen, Fredric A.; Balkey, Kenneth R.

    2006-01-01

    The Boiler and Pressure Vessel Code (BPVC) of the American Society of Mechanical Engineers (ASME) has introduced a risk based approach into Section XI that covers Rules for Inservice Inspection of Nuclear Power Plant Components. The risk based approach requires application of the probabilistic risk assessments (PRA). Because no industry consensus standard existed for PRAs, ASME has developed a standard to evaluate the quality level of an available PRA needed to support a given risk based application. The paper describes the PRA standard, Section XI application of PRAs, and plans for broader applications of PRAs to other ASME nuclear codes and standards. The paper addresses several specific topics of interest to Section XI. Important consideration are special methods (surrogate components) used to overcome the lack of PRA treatments of passive components in PRAs. The approach allows calculations of conditional core damage probabilities both for component failures that cause initiating events and failures in standby systems that decrease the availability of these systems. The paper relates the explicit risk based methods of the new Section XI code cases to the implicit consideration of risk used in the development of Section XI. Other topics include the needed interactions of ISI engineers, plant operating staff, PRA specialists, and members of expert panels that review the risk based programs

  15. Cancer survival analysis using semi-supervised learning method based on Cox and AFT models with L1/2 regularization.

    Science.gov (United States)

    Liang, Yong; Chai, Hua; Liu, Xiao-Ying; Xu, Zong-Ben; Zhang, Hai; Leung, Kwong-Sak

    2016-03-01

    One of the most important objectives of the clinical cancer research is to diagnose cancer more accurately based on the patients' gene expression profiles. Both Cox proportional hazards model (Cox) and accelerated failure time model (AFT) have been widely adopted to the high risk and low risk classification or survival time prediction for the patients' clinical treatment. Nevertheless, two main dilemmas limit the accuracy of these prediction methods. One is that the small sample size and censored data remain a bottleneck for training robust and accurate Cox classification model. In addition to that, similar phenotype tumours and prognoses are actually completely different diseases at the genotype and molecular level. Thus, the utility of the AFT model for the survival time prediction is limited when such biological differences of the diseases have not been previously identified. To try to overcome these two main dilemmas, we proposed a novel semi-supervised learning method based on the Cox and AFT models to accurately predict the treatment risk and the survival time of the patients. Moreover, we adopted the efficient L1/2 regularization approach in the semi-supervised learning method to select the relevant genes, which are significantly associated with the disease. The results of the simulation experiments show that the semi-supervised learning model can significant improve the predictive performance of Cox and AFT models in survival analysis. The proposed procedures have been successfully applied to four real microarray gene expression and artificial evaluation datasets. The advantages of our proposed semi-supervised learning method include: 1) significantly increase the available training samples from censored data; 2) high capability for identifying the survival risk classes of patient in Cox model; 3) high predictive accuracy for patients' survival time in AFT model; 4) strong capability of the relevant biomarker selection. Consequently, our proposed semi

  16. Effect of health risk assessment and counselling on health behaviour and survival in older people: a pragmatic randomised trial.

    Directory of Open Access Journals (Sweden)

    Andreas E Stuck

    2015-10-01

    Full Text Available Potentially avoidable risk factors continue to cause unnecessary disability and premature death in older people. Health risk assessment (HRA, a method successfully used in working-age populations, is a promising method for cost-effective health promotion and preventive care in older individuals, but the long-term effects of this approach are unknown. The objective of this study was to evaluate the effects of an innovative approach to HRA and counselling in older individuals for health behaviours, preventive care, and long-term survival.This study was a pragmatic, single-centre randomised controlled clinical trial in community-dwelling individuals aged 65 y or older registered with one of 19 primary care physician (PCP practices in a mixed rural and urban area in Switzerland. From November 2000 to January 2002, 874 participants were randomly allocated to the intervention and 1,410 to usual care. The intervention consisted of HRA based on self-administered questionnaires and individualised computer-generated feedback reports, combined with nurse and PCP counselling over a 2-y period. Primary outcomes were health behaviours and preventive care use at 2 y and all-cause mortality at 8 y. At baseline, participants in the intervention group had a mean ± standard deviation of 6.9 ± 3.7 risk factors (including unfavourable health behaviours, health and functional impairments, and social risk factors and 4.3 ± 1.8 deficits in recommended preventive care. At 2 y, favourable health behaviours and use of preventive care were more frequent in the intervention than in the control group (based on z-statistics from generalised estimating equation models. For example, 70% compared to 62% were physically active (odds ratio 1.43, 95% CI 1.16-1.77, p = 0.001, and 66% compared to 59% had influenza vaccinations in the past year (odds ratio 1.35, 95% CI 1.09-1.66, p = 0.005. At 8 y, based on an intention-to-treat analysis, the estimated proportion alive was 77.9% in

  17. Advances in Risk Analysis with Big Data.

    Science.gov (United States)

    Choi, Tsan-Ming; Lambert, James H

    2017-08-01

    With cloud computing, Internet-of-things, wireless sensors, social media, fast storage and retrieval, etc., organizations and enterprises have access to unprecedented amounts and varieties of data. Current risk analysis methodology and applications are experiencing related advances and breakthroughs. For example, highway operations data are readily available, and making use of them reduces risks of traffic crashes and travel delays. Massive data of financial and enterprise systems support decision making under risk by individuals, industries, regulators, etc. In this introductory article, we first discuss the meaning of big data for risk analysis. We then examine recent advances in risk analysis with big data in several topic areas. For each area, we identify and introduce the relevant articles that are featured in the special issue. We conclude with a discussion on future research opportunities. © 2017 Society for Risk Analysis.

  18. Restoration Survival: Revisiting Patients' Risk Factors Through a Systematic Literature Review

    NARCIS (Netherlands)

    Sande, F.H. van de; Collares, K.; Correa, M.B.; Cenci, M.S.; Demarco, F.F.; Opdam, N.J.M.

    2016-01-01

    A literature review was conducted to investigate the influence of patient-related factors on restoration survival in posterior permanent teeth as well as to report the methods used to collect these factors. The selection of articles on longitudinal clinical studies investigating the survival of

  19. Risks, benefits and survival strategies-views from female sex workers in Savannakhet, Laos

    Directory of Open Access Journals (Sweden)

    Phrasisombath Ketkesone

    2012-11-01

    Full Text Available Abstract Background Female sex workers (FSWs are vulnerable to sexually transmitted infections (STIs and encounter socio-economic and health problems, including STIs/HIV, unintended pregnancy and complications from unsafe abortion, stigma, violence, and drug addiction. Reducing risks associated with sex work requires an understanding of the social and cultural context in which sex workers live and work. This study aimed to explore the working environment and perceived risks among FSWs in Savannakhet province in Laos. Methods Five focus group discussions (FGDs and seven interviews were conducted with FSWs in Kaysone Phomvihan district in Laos. Latent content analysis was used to analyze the transcribed text. Results The results revealed that the FSWs were aware of risks but they also talked about benefits related to their work. The risks were grouped into six categories: STIs/HIV, unintended pregnancy, stigma, violence, being cheated, and social and economic insecurity. The reported benefits were financial security, fulfilling social obligations, and sexual pleasure. The FSWs reported using a number of strategies to reduce risks and increase benefits. Conclusions The desire to be self-sufficient and earn as much money as possible put the FSWs in disadvantaged and vulnerable situations. Fear of financial insecurity, obligations to support one’s family and the need to secure the future influenced FSWs’ decisions to have safe or unsafe sex. The FSWs were, however, not only victims. They also had some control over their lives and working environment, with most viewing their work as an easy and good way of earning money.

  20. Race and risk of metastases and survival after radical prostatectomy: Results from the SEARCH database.

    Science.gov (United States)

    Freedland, Stephen J; Vidal, Adriana C; Howard, Lauren E; Terris, Martha K; Cooperberg, Matthew R; Amling, Christopher L; Kane, Christopher J; Aronson, William J

    2017-11-01

    Black race is associated with prostate cancer (PC) diagnosis and poor outcome. Previously, the authors reported that black men undergoing radical prostatectomy (RP) in equal-access hospitals had an increased risk of biochemical disease recurrence (BCR), but recurrences were equally aggressive as those occurring in white men. The authors examined the association between race and long-term outcomes after RP. Data regarding 1665 black men (37%) and 2791 white men (63%) undergoing RP were analyzed. Using Cox models, the authors tested the association between race and BCR, BCR with a prostate-specific antigen (PSA) doubling time black men (all PBlack men were found to have a more recent surgery year (Pblack race was associated with increased BCR (P = .003) and reduced overall death (P = .017). On multivariable analysis, black race was not found to be associated with BCR (hazard ratio [HR], 1.07; P = .26), aggressive recurrence (HR, 1.14; P = .42), metastasis (HR, 1.24; P = .21), PC-specific death (HR, 1.03; P = .91), or overall death (HR, 1.03; P = .67). Among men undergoing RP at equal-access centers, although black men were found to have an increased risk of BCR, they had similar risks of aggressive disease recurrence, metastasis, and PC-specific death compared with white men, and the risk of BCR was found to be similar after controlling for risk parameters. Longer follow-up is needed to confirm these findings. Cancer 2017;123:4199-4206. © 2017 American Cancer Society. © 2017 American Cancer Society.

  1. 38 CFR 75.115 - Risk analysis.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Risk analysis. 75.115 Section 75.115 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) INFORMATION SECURITY MATTERS Data Breaches § 75.115 Risk analysis. If a data breach involving sensitive personal information that is processed or...

  2. Modeling time-to-event (survival) data using classification tree analysis.

    Science.gov (United States)

    Linden, Ariel; Yarnold, Paul R

    2017-12-01

    Time to the occurrence of an event is often studied in health research. Survival analysis differs from other designs in that follow-up times for individuals who do not experience the event by the end of the study (called censored) are accounted for in the analysis. Cox regression is the standard method for analysing censored data, but the assumptions required of these models are easily violated. In this paper, we introduce classification tree analysis (CTA) as a flexible alternative for modelling censored data. Classification tree analysis is a "decision-tree"-like classification model that provides parsimonious, transparent (ie, easy to visually display and interpret) decision rules that maximize predictive accuracy, derives exact P values via permutation tests, and evaluates model cross-generalizability. Using empirical data, we identify all statistically valid, reproducible, longitudinally consistent, and cross-generalizable CTA survival models and then compare their predictive accuracy to estimates derived via Cox regression and an unadjusted naïve model. Model performance is assessed using integrated Brier scores and a comparison between estimated survival curves. The Cox regression model best predicts average incidence of the outcome over time, whereas CTA survival models best predict either relatively high, or low, incidence of the outcome over time. Classification tree analysis survival models offer many advantages over Cox regression, such as explicit maximization of predictive accuracy, parsimony, statistical robustness, and transparency. Therefore, researchers interested in accurate prognoses and clear decision rules should consider developing models using the CTA-survival framework. © 2017 John Wiley & Sons, Ltd.

  3. Survived infancy but still vulnerable: spatial-temporal trends and risk factors for child mortality in the Agincourt rural sub-district, South Africa, 1992-2007

    Directory of Open Access Journals (Sweden)

    Benn Sartorius

    2011-05-01

    Full Text Available Targeting of health interventions to poor children at highest risk of mortality are promising approaches for enhancing equity. Methods have emerged to accurately quantify excess risk and identify space-time disparities. This provides useful and detailed information for guiding policy. A spatio-temporal analysis was performed to identify risk factors associated with child (1-4 years mortality in the Agincourt sub-district, South Africa, to assess temporal changes in child mortality patterns within the study site between 1992 and 2007, and to produce all-cause and cause-specific mortality maps to identify high risk areas. Demographic, maternal, paternal and fertility-related factors, household mortality experience, distance to health care facility and socio-economic status were among the examined risk factors. The analysis was carried out by fitting a Bayesian discrete time Bernoulli survival geostatistical model using Markov chain Monte Carlo simulation. Bayesian kriging was used to produce mortality risk maps. Significant temporal increase in child mortality was observed due to the HIV epidemic. A distinct spatial risk pattern was observed with higher risk areas being concentrated in poorer settlements on the eastern part of the study area, largely inhabited by former Mozambican refugees. The major risk factors for childhood mortality, following multivariate adjustment, were mother’s death (especially when due to HIV and tuberculosis, greater number of children under 5 years living in the same household and winter season. This study demonstrates the use of Bayesian geostatistical models for accurately quantifying risk factors and producing maps of child mortality risk in a health and demographic surveillance system. According to the space-time analysis, the southeast and upper central regions of the site appear to have the highest mortality risk. The results inform policies to address health inequalities in the Agincourt sub-district and to

  4. A background to risk analysis. Vol. 4

    International Nuclear Information System (INIS)

    Taylor, J.R.

    1979-01-01

    This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques described are somewhat experimental. The report is written in an introductory style, but where some point needs further justification or evaluation, this is given in the form of a chapter appendix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 4 treats human error in plant operation. (BP)

  5. Survival and Locomotory Behavior of Earwigs After Exposure to Reduced-Risk Insecticides.

    Science.gov (United States)

    Freitas, Catarina D; Gontijo, Lessando M; Guedes, Raul Narciso C; Chediak, Mateus

    2017-08-01

    The conservation of natural enemies is an important tactic to promote biological control of arthropod pests. The earwig Doru luteipes (Sccuder) is the most important predator of the fall armyworm Spodoptera frugiperda (J.E. Smith) in corn fields. One way of conserving these predators in the field is by using only selective insecticides when the pest population reaches the economic threshold. Some recent insecticides such as azadirachtin, chlorantraniliprole, and novaluron have been claimed to pose reduced risk for natural enemies. Nevertheless, there is a dearth of information regarding the selectivity of these insecticides upon earwigs in specific. In this study, we carried out a series of laboratory assays to examine the survivorship and locomotory behavior of D. luteipes after exposure to fresh dry residue of azadirachtin, chlorantraniliprole, and novaluron. Our results show a significant survival reduction for D. luteipes nymphs exposed to fresh residues of chlorantraniliprole and novaluron. In the behavioral studies, adults of D. luteipes stopped more often, spent more time resting (inactive), and moved more slowly immediately after exposure to chlorantraniliprole residue. These results suggest that chlorantraniliprole may mediate an impaired movement and a behavior arrestment of earwigs after contact with this insecticide fresh residue. This could translate into reduced foraging efficiency, and increase exposure and insecticide uptake. Although chlorantraniliprole and novaluron showed a potential to undermine the biological control provided by earwigs, it is yet essential to conduct field trials in order to confirm our laboratory results. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. SURVIVAL ANALYSIS AND GROWTH OF Cordia trichotoma, BORAGINACEAE, LAMIALES, IN MATO GROSSO DO SUL STATE, BRAZIL

    Directory of Open Access Journals (Sweden)

    Sergio Luiz Salvadori

    2013-12-01

    Full Text Available http://dx.doi.org/10.5902/1980509812357The evaluation of a plant survival percentage and growth may reflect its competitive ability in plantcommunity. Cordia trichotoma is a common native tree in Mato Grosso do Sul State and one of the mostpromising for planting. This study monitored the survival percentage and growth of Cordia trichotomaunder different conditions such as weeding and receiving or not fertilization. The experiment started inSeptember 2008 and it was concluded in March 2010. The seeds collection and sowing were held in urbanarea of Mundo Novo Municipality and the area for permanent planting to measure seedlings survival andgrowth was set at Japorã Municipality, Fazenda Santa Clara. Seedlings were planted in two categories: theuse or not of fertilizer and crowing resulting in four distinct groups: block fertilizer bare earth (ATN, bareland block without fertilizer (BTN, fertilizer and crown block (AC and without fertilizer and crownedblock (BC. The results indicated high survival of Cordia trichotoma in the seedling transplant system from bed to bags. The BC block showed the highest percentage of survival, but the smaller increments in height.The AC, ATN and BTN blocks presented the same survival pattern and similar average growth. However,there may be differences in nutritional and chemical composition of the soil suggesting sector analysis forfuture studies.

  7. Association of Ovarian Tumor β2-Adrenergic Receptor Status with Ovarian Cancer Risk Factors and Survival.

    Science.gov (United States)

    Huang, Tianyi; Tworoger, Shelley S; Hecht, Jonathan L; Rice, Megan S; Sood, Anil K; Kubzansky, Laura D; Poole, Elizabeth M

    2016-12-01

    The β 2 -adrenergic signaling pathway mediates the effects of chronic stress on ovarian cancer progression in mouse models. The relevance of this pathway to human ovarian cancer remains unknown. We assessed tumor expression of β 2 -adrenergic receptor (ADRB2) using tissue microarrays in 237 ovarian cancer cases from the Nurses' Health Studies (NHS/NHSII). Competing risks Cox regression was used to evaluate whether associations of reproductive, hormonal, and psychosocial factors with ovarian cancer risk differed by ADRB2. We also examined the association between tumor ADRB2 expression and ovarian cancer survival. Forty-five (19%) cases were positive for ADRB2 staining. High levels of anxiety symptoms were positively associated with ADRB2-positive tumors (HR, 2.59; 95% confidence interval [CI], 1.15-5.84) but not with ADRB2-negative tumors (HR, 1.16; 95% CI, 0.81-1.66; P heterogeneity = 0.07). We observed similar results for depression. No associations were observed for job strain, caregiving stress, or widowhood for either positive or negative ADRB2 status. Lifetime ovulatory years were more strongly associated with ADRB2-positive tumors (HR per 5 years, 1.60; 95% CI, 1.15-2.21) compared with ADRB2-negative tumors (HR, 1.11; 95% CI, 0.96-1.27; P heterogeneity = 0.04). Significant heterogeneity by ADRB2 was also observed for parity (P heterogeneity = 0.01), oral contraceptive use (P heterogeneity = 0.03), and age at menopause (P heterogeneity = 0.04). Tumor expression of ADRB2 was not associated with ovarian cancer mortality (HR, 1.05; 95% CI, 0.69-1.59). Several stress- and ovulation-related factors were differentially associated with ovarian tumors responsive to β 2 -adrenergic signaling. Replication in larger studies is warranted to confirm the role of β 2 -adrenergic signaling in ovarian cancer etiology. Cancer Epidemiol Biomarkers Prev; 25(12); 1587-94. ©2016 AACR. ©2016 American Association for Cancer Research.

  8. Re-analysis of survival data of cancer patients utilizing additive homeopathy.

    Science.gov (United States)

    Gleiss, Andreas; Frass, Michael; Gaertner, Katharina

    2016-08-01

    In this short communication we present a re-analysis of homeopathic patient data in comparison to control patient data from the same Outpatient´s Unit "Homeopathy in malignant diseases" of the Medical University of Vienna. In this analysis we took account of a probable immortal time bias. For patients suffering from advanced stages of cancer and surviving the first 6 or 12 months after diagnosis, respectively, the results show that utilizing homeopathy gives a statistically significant (p<0.001) advantage over control patients regarding survival time. In conclusion, bearing in mind all limitations, the results of this retrospective study suggest that patients with advanced stages of cancer might benefit from additional homeopathic treatment until a survival time of up to 12 months after diagnosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Iterative Bayesian Model Averaging: a method for the application of survival analysis to high-dimensional microarray data

    Directory of Open Access Journals (Sweden)

    Raftery Adrian E

    2009-02-01

    Full Text Available Abstract Background Microarray technology is increasingly used to identify potential biomarkers for cancer prognostics and diagnostics. Previously, we have developed the iterative Bayesian Model Averaging (BMA algorithm for use in classification. Here, we extend the iterative BMA algorithm for application to survival analysis on high-dimensional microarray data. The main goal in applying survival analysis to microarray data is to determine a highly predictive model of patients' time to event (such as death, relapse, or metastasis using a small number of selected genes. Our multivariate procedure combines the effectiveness of multiple contending models by calculating the weighted average of their posterior probability distributions. Our results demonstrate that our iterative BMA algorithm for survival analysis achieves high prediction accuracy while consistently selecting a small and cost-effective number of predictor genes. Results We applied the iterative BMA algorithm to two cancer datasets: breast cancer and diffuse large B-cell lymphoma (DLBCL data. On the breast cancer data, the algorithm selected a total of 15 predictor genes across 84 contending models from the training data. The maximum likelihood estimates of the selected genes and the posterior probabilities of the selected models from the training data were used to divide patients in the test (or validation dataset into high- and low-risk categories. Using the genes and models determined from the training data, we assigned patients from the test data into highly distinct risk groups (as indicated by a p-value of 7.26e-05 from the log-rank test. Moreover, we achieved comparable results using only the 5 top selected genes with 100% posterior probabilities. On the DLBCL data, our iterative BMA procedure selected a total of 25 genes across 3 contending models from the training data. Once again, we assigned the patients in the validation set to significantly distinct risk groups (p

  10. Reliability and validity of risk analysis

    International Nuclear Information System (INIS)

    Aven, Terje; Heide, Bjornar

    2009-01-01

    In this paper we investigate to what extent risk analysis meets the scientific quality requirements of reliability and validity. We distinguish between two types of approaches within risk analysis, relative frequency-based approaches and Bayesian approaches. The former category includes both traditional statistical inference methods and the so-called probability of frequency approach. Depending on the risk analysis approach, the aim of the analysis is different, the results are presented in different ways and consequently the meaning of the concepts reliability and validity are not the same.

  11. Young age: an independent risk factor for disease-free survival in women with operable breast cancer

    International Nuclear Information System (INIS)

    Han, Wonshik; Kim, Seok Won; Ae Park, In; Kang, Daehee; Kim, Sung-Won; Youn, Yeo-Kyu; Oh, Seung Keun; Choe, Kuk Jin; Noh, Dong-Young

    2004-01-01

    The incidence of breast cancer in young women (age < 35) is low. The biology of the disease in this age group is poorly understood, and there are conflicting data regarding the prognosis for these women compared to older patients. We retrospectively analyzed 2040 consecutive primary invasive breast cancer patients who underwent surgical procedures at our institution between 1990 and 1999. The younger age group was defined as patients aged <35 years at the time of diagnosis. The clinicopathological characteristics and treatment outcomes were compared between younger and older age groups. A total of 256 (12.5%) patients were aged <35. There was a significantly higher incidence of nuclear grade 3 and medullary histological-type tumors in younger patients compared to older patients. Axillary lymph node status, T stage, histological grade, c-erbB2 expression and estrogen receptor status did not differ significantly between the two age groups. Younger patients had a greater probability of recurrence and death at all time periods. Although there was no significant difference in disease-free survival between the two age groups in lymph node-negative patients, the younger group showed worse prognosis among lymph node-positive patients (p < 0.001). In multivariate analysis, young age remained a significant predictor of recurrence (p = 0.010). Young age (<35) is an independent risk factor for relapse in operable breast cancer patients

  12. Probabilistic risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Hauptmanns, U.

    1988-01-01

    Risk analysis is applied if the calculation of risk from observed failures is not possible, because events contributing substantially to risk are too seldom, as in the case of nuclear reactors. The process of analysis provides a number of benefits. Some of them are listed. After this by no means complete enumeration of possible benefits to be derived from a risk analysis. An outline of risk studiesd for PWR's with some comments on the models used are given. The presentation is indebted to the detailed treatment of the subject given in the PRA Procedures Guide. Thereafter some results of the German Risk Study, Phase B, which is under way are communicated. The paper concludes with some remarks on probabilistic considerations in licensing procedures. (orig./DG)

  13. Survival or Mortality: Does Risk Attribute Framing Influence Decision-Making Behavior in a Discrete Choice Experiment?

    Science.gov (United States)

    Veldwijk, Jorien; Essers, Brigitte A B; Lambooij, Mattijs S; Dirksen, Carmen D; Smit, Henriette A; de Wit, G Ardine

    2016-01-01

    To test how attribute framing in a discrete choice experiment (DCE) affects respondents' decision-making behavior and their preferences. Two versions of a DCE questionnaire containing nine choice tasks were distributed among a representative sample of the Dutch population aged 55 to 65 years. The DCE consisted of four attributes related to the decision regarding participation in genetic screening for colorectal cancer (CRC). The risk attribute included was framed positively as the probability of surviving CRC and negatively as the probability of dying from CRC. Panel mixed-logit models were used to estimate the relative importance of the attributes. The data of the positively and negatively framed DCE were compared on the basis of direct attribute ranking, dominant decision-making behavior, preferences, and importance scores. The majority (56%) of the respondents ranked survival as the most important attribute in the positively framed DCE, whereas only a minority (8%) of the respondents ranked mortality as the most important attribute in the negatively framed DCE. Respondents made dominant choices based on survival significantly more often than based on mortality. The framing of the risk attribute significantly influenced all attribute-level estimates and resulted in different preference structures among respondents in the positively and negatively framed data set. Risk framing affects how respondents value the presented risk. Positive risk framing led to increased dominant decision-making behavior, whereas negative risk framing led to risk-seeking behavior. Attribute framing should have a prominent part in the expert and focus group interviews, and different types of framing should be used in the pilot version of DCEs as well as in actual DCEs to estimate the magnitude of the effect of choosing different types of framing. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  14. Bias in risk-benefit analysis

    International Nuclear Information System (INIS)

    Mazur, A.

    1985-01-01

    Risk-benefit analysis has become popular in the past decade as a means of improving decision making, especially in the area of technology policy. Here risk-benefit analysis is compared to other (equally defensible) approaches to decision making, showing how it favors some political interests more than others, and suggesting why it has recently come to the fore as a tool of political analysis. A considerable portion of the discussion concerns nuclear power. 6 references

  15. Codevelopment of conceptual understanding and critical attitude: toward a systemic analysis of the survival blanket

    Science.gov (United States)

    Viennot, Laurence; Décamp, Nicolas

    2016-01-01

    One key objective of physics teaching is the promotion of conceptual understanding. Additionally, the critical faculty is universally seen as a central quality to be developed in students. In recent years, however, teaching objectives have placed stronger emphasis on skills than on concepts, and there is a risk that conceptual structuring may be disregarded. The question therefore arises as to whether it is possible for students to develop a critical stance without a conceptual basis, leading in turn to the issue of possible links between the development of conceptual understanding and critical attitude. In an in-depth study to address these questions, the participants were seven prospective physics and chemistry teachers. The methodology included a ‘teaching interview’, designed to observe participants’ responses to limited explanations of a given phenomenon and their ensuing intellectual satisfaction or frustration. The explanatory task related to the physics of how a survival blanket works, requiring a full and appropriate system analysis of the blanket. The analysis identified five recurrent lines of reasoning and linked these to judgments of adequacy of explanation, based on metacognitive/affective (MCA) factors, intellectual (dis)satisfaction and critical stance. Recurrent themes and MCA factors were used to map the intellectual dynamics that emerged during the interview process. Participants’ critical attitude was observed to develop in strong interaction with their comprehension of the topic. The results suggest that most students need to reach a certain level of conceptual mastery before they can begin to question an oversimplified explanation, although one student’s replies show that a different intellectual dynamics is also possible. The paper ends with a discussion of the implications of these findings for future research and for decisions concerning teaching objectives and the design of learning environments.

  16. When will I succeed in my first-year diploma? Survival analysis in Dutch higher education

    NARCIS (Netherlands)

    Bruinsma, Marjon; Jansen, Ellen P. W. A.

    2009-01-01

    The goal of this study was to illustrate survival analysis with higher education data and gain insight into a limited set of factors that predict when students passed their first-year examination at a Dutch university. Study participants consisted of 565 first-year students in four departments. Data

  17. Revealing the equivalence of two clonal survival models by principal component analysis

    International Nuclear Information System (INIS)

    Lachet, Bernard; Dufour, Jacques

    1976-01-01

    The principal component analysis of 21 chlorella cell survival curves, adjusted by one-hit and two-hit target models, lead to quite similar projections on the principal plan: the homologous parameters of these models are linearly correlated; the reason for the statistical equivalence of these two models, in the present state of experimental inaccuracy, is revealed [fr

  18. Survival analysis of postoperative nausea and vomiting in patients receiving patient-controlled epidural analgesia

    Directory of Open Access Journals (Sweden)

    Shang-Yi Lee

    2014-11-01

    Conclusion: Survival analysis using Cox regression showed that the average consumption of opioids played an important role in postoperative nausea and vomiting, a result not found by logistic regression. Therefore, the incidence of postoperative nausea and vomiting in patients cannot be reliably determined on the basis of a single visit at one point in time.

  19. It's Deja Vu All over Again: Using Multiple-Spell Discrete-Time Survival Analysis.

    Science.gov (United States)

    Willett, John B.; Singer, Judith D.

    1995-01-01

    The multiple-spell discrete-time survival analysis method is introduced and illustrated using longitudinal data on exit from and reentry into the teaching profession. The method is applicable to many educational problems involving the sequential occurrence of disparate events or episodes. (SLD)

  20. Association between platelet to lymphocyte ratio (PLR) and overall survival (OS) of hepatocellular carcinoma (HCC): A meta-analysis.

    Science.gov (United States)

    Hu, D-H; Yu, S-M

    2017-08-30

    Some studies investigated the association between platelet-to-lymphocyte ratio (PLR) and the survival of hepatocellular carcinoma (HCC). However, the results remained inconclusive. Thus, we performed this meta-analysis. Published studies were searched in PubMed and EMBASE. The strength of association was assessed by calculating odds ratios (OR) and 95% confidence interval (CI). In total, 6 studies with 1446 HCC patients were included in this meta-analysis. HCC with higher PLR showed an increased death risk (OR = 1.59; 95%CI, 1.15-2.20; P < 0.0001). However, the heterogeneity was high (I2=89.2%). When the study by Li et al. was excluded, the heterogeneity decreased (I2=20%). Further, the result was still positive (OR = 1.70; 95%CI, 1.42-2.04; P < 0.00001). In conclusion, this meta-analysis suggested that PLR was significantly associated with the OS of HCC.

  1. Influence of an elevated nutrition risk score (NRS) on survival in patients following gastrectomy for gastric cancer.

    Science.gov (United States)

    Bachmann, J; Müller, T; Schröder, A; Riediger, C; Feith, M; Reim, D; Friess, H; Martignoni, M E

    2015-07-01

    In the last years, the impact of weight loss in patients with malignant tumors has come more and more into the focus of clinical research, as the occurrence of weight loss is often associated with a reduced survival. Weight loss can be a hint for metastases in patients suffering from malignant tumors; furthermore, these patients are usually not able to be treated with chemotherapy. The aim of the study was to show the influence of weight loss and an elevated nutrition risk score on survival following tumor resection in patients suffering from gastric cancer. In 99 patients in whom a gastrectomy due to gastric cancer was performed, the nutrition risk score was calculated and its influence on mortality, morbidity and survival was analyzed. Of the included patients, 45 % of the patients gave a history of weight loss; they had significantly more often a NRS ≥ 3. In UICC stage 1a/b, a NRS ≥ 3 was associated with a significantly reduced survival compared to patients with a NRS gastric cancer, the influence of a reduced NRS is negligible.

  2. [Quality of life and overall survival in high risk patients after radical cystectomy with a simple urinary derivation].

    Science.gov (United States)

    Mucciardi, Giuseppe; Macchione, Luciano; Galì, Alessandro; di Benedetto, Antonina; Subba, Enrica; Pappalardo, Rosa; Mucciardi, Massimo; Butticè, Salvatore; Inferrera, Antonino; Magno, Carlo

    2015-01-01

    To evaluate quality of life (QoL) and overall survival after radical cystectomy with cutaneous ureterostomies for locally advanced bladder cancer in elderly patients with high surgical risk. Fifty eight patients older than 74 years (mean age 80,6±4,3) with locally advanced bladder cancer (group A), underwent radical cystectomy and ureterocutaneous diversion. Patients completed the EORTC QLQC30 before and six months after surgery to assess functional, clinical and QoL outcomes. The same evaluation was carried out in a control group (group B) of 29 patients (mean age 82,3±3,8 years), who had refused cystectomy. Questionnaires were also administered to patients of both groups who survived at least 20 months and 5 years. All patients presented with an ASA score ≥3. Mean hospital stay was 15.1 days (±4.8) in group A and 23.5 days (±4.1) in Group B. No intraoperative complications occurred in group A. Postoperative overall survival evaluated within 6 months in group A was 97% versus 79% in group B (pbladder cancer and high operative risk. Comparison between two groups showed a statistically significant difference for almost all the Qol related parameters and for short and medium term overall survival. Copyright © 2012 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. Collision Risk Analysis for HSC

    DEFF Research Database (Denmark)

    Urban, Jesper; Pedersen, Preben Terndrup; Simonsen, Bo Cerup

    1999-01-01

    High Speed Craft (HSC) have a risk profile, which is distinctly different from conventional ferries. Due to different hull building material, structural layout, compartmentation and operation, both frequency and consequences of collision and grounding accidents must be expected to be different fr...

  4. On the analysis of clonogenic survival data: Statistical alternatives to the linear-quadratic model

    International Nuclear Information System (INIS)

    Unkel, Steffen; Belka, Claus; Lauber, Kirsten

    2016-01-01

    The most frequently used method to quantitatively describe the response to ionizing irradiation in terms of clonogenic survival is the linear-quadratic (LQ) model. In the LQ model, the logarithm of the surviving fraction is regressed linearly on the radiation dose by means of a second-degree polynomial. The ratio of the estimated parameters for the linear and quadratic term, respectively, represents the dose at which both terms have the same weight in the abrogation of clonogenic survival. This ratio is known as the α/β ratio. However, there are plausible scenarios in which the α/β ratio fails to sufficiently reflect differences between dose-response curves, for example when curves with similar α/β ratio but different overall steepness are being compared. In such situations, the interpretation of the LQ model is severely limited. Colony formation assays were performed in order to measure the clonogenic survival of nine human pancreatic cancer cell lines and immortalized human pancreatic ductal epithelial cells upon irradiation at 0-10 Gy. The resulting dataset was subjected to LQ regression and non-linear log-logistic regression. Dimensionality reduction of the data was performed by cluster analysis and principal component analysis. Both the LQ model and the non-linear log-logistic regression model resulted in accurate approximations of the observed dose-response relationships in the dataset of clonogenic survival. However, in contrast to the LQ model the non-linear regression model allowed the discrimination of curves with different overall steepness but similar α/β ratio and revealed an improved goodness-of-fit. Additionally, the estimated parameters in the non-linear model exhibit a more direct interpretation than the α/β ratio. Dimensionality reduction of clonogenic survival data by means of cluster analysis was shown to be a useful tool for classifying radioresistant and sensitive cell lines. More quantitatively, principal component analysis allowed

  5. Survival Rate and Associated Factors of Childhood Leukemia in Iran: A Systematic Review and Meta Analysis

    Directory of Open Access Journals (Sweden)

    Yousef Veisani

    2017-02-01

    Full Text Available Context Resent reviews have shown that about 18% of all child cancers are leukemia. Track of the survival rate can help researchers improve quality of life of patients through improving screening or discovery of better treatments. Objectives This review aimed at estimating the 5-year survival rates and associated factors of childhood leukemia in Iran. Data Sources We carried out a systematic review through search of relevant studies published in English (PubMed, Scopus, Google scholar, and ISI and Persian databases (Magiran, Medlib, SID, and Iran Medex. Study Selection The study included all epidemiologic studies that estimated survival rate in children with leukemia in Iran during years 2002 to 2015, and a standardized manner was used for extraction of information. Data Extraction The entire text or summary of all searched articles was extracted and then, related articles were selected, and irrelevant ones were excluded. Fixed and random effects models were calculated by the STATA using standard meta-analysis methods. Heterogeneity was assessed by I² statistics. Results The overall 5-year survival rate in patients with childhood leukemia in Iran was 0.65 (95% CI, 0.62 to 0.67, 10 studies, in the acute lymphoblastic leukemia (ALL subtype was 71.0% (95% CI: 68.0 to 74.0, and in the acute myeloid leukemia (AML subtype was 46.0%. Results of the meta analysis showed significant poor survival with relapse (heart rate (HR 1.59, 95% confidence interval (CI 1.27 to 1.98 and white blood count (WBC counts ≥ 50,000 (HR 2.92, 95% CI 1.23 to 4.60. Conclusions The results showed that 5-year survival rates in patients with AML were lower than patients with ALL. The results of this meta analysis strongly support the need for future research, action, and guidance for clinicians to improve health-related quality of life and outcomes for children with leukemia.

  6. Generalized indices for radiation risk analysis

    International Nuclear Information System (INIS)

    Bykov, A.A.; Demin, V.F.

    1989-01-01

    A new approach to ensuring nuclear safety has begun forming since the early eighties. The approach based on the probabilistic safety analysis, the principles of acceptable risk, the optimization of safety measures, etc. has forced a complex of adequate quantitative methods of assessment, safety analysis and risk management to be developed. The method of radiation risk assessment and analysis hold a prominent place in the complex. National and international research and regulatory organizations ICRP, IAEA, WHO, UNSCEAR, OECD/NEA have given much attention to the development of the conceptual and methodological basis of those methods. Some resolutions of the National Commission of Radiological Protection (NCRP) and the Problem Commission on Radiation Hygiene of the USSR Ministry of Health should be also noted. Both CBA (cost benefit analysis) and other methods of radiation risk analysis and safety management use a system of natural and socio-economic indices characterizing the radiation risk or damage. There exist a number of problems associated with the introduction, justification and use of these indices. For example, the price, a, of radiation damage, or collective dose unit, is a noteworthy index. The difficulties in its qualitative and quantitative determination are still an obstacle for a wide application of CBA to the radiation risk analysis and management. During recent 10-15 years these problems have been a subject of consideration for many authors. The present paper also considers the issues of the qualitative and quantitative justification of the indices of radiation risk analysis

  7. Final analysis of survival outcomes in the phase 3 FIRST trial of up-front treatment for multiple myeloma.

    Science.gov (United States)

    Facon, Thierry; Dimopoulos, Meletios A; Dispenzieri, Angela; Catalano, John V; Belch, Andrew; Cavo, Michele; Pinto, Antonello; Weisel, Katja; Ludwig, Heinz; Bahlis, Nizar J; Banos, Anne; Tiab, Mourad; Delforge, Michel; Cavenagh, Jamie D; Geraldes, Catarina; Lee, Je-Jung; Chen, Christine; Oriol, Albert; De La Rubia, Javier; White, Darrell; Binder, Daniel; Lu, Jin; Anderson, Kenneth C; Moreau, Philippe; Attal, Michel; Perrot, Aurore; Arnulf, Bertrand; Qiu, Lugui; Roussel, Murielle; Boyle, Eileen; Manier, Salomon; Mohty, Mohamad; Avet-Loiseau, Herve; Leleu, Xavier; Ervin-Haynes, Annette; Chen, Guang; Houck, Vanessa; Benboubker, Lotfi; Hulin, Cyrille

    2018-01-18

    This FIRST trial final analysis examined survival outcomes in patients with transplant-ineligible newly diagnosed multiple myeloma (NDMM) treated with lenalidomide and low-dose dexamethasone until disease progression (Rd continuous), Rd for 72 weeks (18 cycles; Rd18), or melphalan, prednisone, and thalidomide (MPT; 72 weeks). The primary endpoint was progression-free survival (PFS; primary comparison: Rd continuous vs MPT). Overall survival (OS) was a key secondary endpoint (final analysis prespecified ≥60 months' follow-up). Patients were randomized to Rd continuous (n = 535), Rd18 (n = 541), or MPT (n = 547). At a median follow-up of 67 months, PFS was significantly longer with Rd continuous vs MPT (hazard ratio [HR], 0.69; 95% confidence interval [CI], 0.59-0.79; P < .00001) and was similarly extended vs Rd18. Median OS was 10 months longer with Rd continuous vs MPT (59.1 vs 49.1 months; HR, 0.78; 95% CI, 0.67-0.92; P = .0023), and similar with Rd18 (62.3 months). In patients achieving complete or very good partial responses, Rd continuous had an ≈30-month longer median time to next treatment vs Rd18 (69.5 vs 39.9 months). Over half of all patients who received second-line treatment were given a bortezomib-based therapy. Second-line outcomes were improved in patients receiving bortezomib after Rd continuous and Rd18 vs after MPT. No new safety concerns, including risk for secondary malignancies, were observed. Treatment with Rd continuous significantly improved survival outcomes vs MPT, supporting Rd continuous as a standard of care for patients with transplant-ineligible NDMM. This trial was registered at www.clinicaltrials.gov as #NCT00689936 and EudraCT as 2007-004823-39. © 2018 by The American Society of Hematology.

  8. Fissure sealants in caries prevention:a practice-based study using survival analysis

    OpenAIRE

    Leskinen, K. (Kaja)

    2010-01-01

    Abstract The purpose of this study was to analyse the effectiveness and cost of fissure sealant treatment in preventing dental caries in children in a practice-based research network using survival analysis. The survival times of first permanent molars in children were analysed in three countries: in Finland (age cohorts 1970–1972 and 1980–1982), in Sweden (1980–1982) and in Greece (1980–1982), and additionally at two municipal health centres in Finland (age cohorts 1988–1990 in Kemi...

  9. Development and validation of risk prediction equations to estimate survival in patients with colorectal cancer: cohort study

    OpenAIRE

    Hippisley-Cox, Julia; Coupland, Carol

    2017-01-01

    Objective: To develop and externally validate risk prediction equations to estimate absolute and conditional survival in patients with colorectal cancer. \\ud \\ud Design: Cohort study.\\ud \\ud Setting: General practices in England providing data for the QResearch database linked to the national cancer registry.\\ud \\ud Participants: 44 145 patients aged 15-99 with colorectal cancer from 947 practices to derive the equations. The equations were validated in 15 214 patients with colorectal cancer ...

  10. Factors associated with dental implant survival: a 4-year retrospective analysis.

    Science.gov (United States)

    Zupnik, Jamie; Kim, Soo-woo; Ravens, Daniel; Karimbux, Nadeem; Guze, Kevin

    2011-10-01

    Dental implants are a predictable treatment option for replacing missing teeth and have strong survival and success outcomes. However, previous research showed a wide array of potential risk factors that may have contributed to dental implant failures. The objectives of this study are to study if implant survival rates were affected by known risk factors and risk indicators that may have contributed to implant failures. The secondary outcome measures were whether the level of expertise of the periodontal residents affected success rates and how the rate of implant success at the Harvard School of Dental Medicine (HSDM) compared to published standards. A retrospective chart review of patients at the HSDM who had one of two types of rough-surface implants (group A or B) placed by periodontology residents from 2003 to 2006 was performed. Demographic, health, and implant data were collected and analyzed by multimodel analyses to determine failure rates and any factors that may have increased the likelihood of an implant failure. The study cohort included 341 dental implants. The odds ratio for an implant failure was most clearly elevated for diabetes (2.59 implant surface group B (7.84), and male groups (4.01). There was no significant difference regarding the resident experience. The success rate for HSDM periodontology residents was 96.48% during the 4-year study period. This study demonstrates that implant success rates at HSDM fell within accepted published standards, confirmed previously identified risk factors for a failure, and potentially suggested that other acknowledged risk factors could be controlled for. Furthermore, the level of experience of the periodontology resident did not have an impact on survival outcomes.

  11. Mechanisms and mediation in survival analysis: towards an integrated analytical framework.

    LENUS (Irish Health Repository)

    Haase, Trutz

    2016-02-29

    A wide-ranging debate has taken place in recent years on mediation analysis and causal modelling, raising profound theoretical, philosophical and methodological questions. The authors build on the results of these discussions to work towards an integrated approach to the analysis of research questions that situate survival outcomes in relation to complex causal pathways with multiple mediators. The background to this contribution is the increasingly urgent need for policy-relevant research on the nature of inequalities in health and healthcare.

  12. Two-stage meta-analysis of survival data from individual participants using percentile ratios

    Science.gov (United States)

    Barrett, Jessica K; Farewell, Vern T; Siannis, Fotios; Tierney, Jayne; Higgins, Julian P T

    2012-01-01

    Methods for individual participant data meta-analysis of survival outcomes commonly focus on the hazard ratio as a measure of treatment effect. Recently, Siannis et al. (2010, Statistics in Medicine 29:3030–3045) proposed the use of percentile ratios as an alternative to hazard ratios. We describe a novel two-stage method for the meta-analysis of percentile ratios that avoids distributional assumptions at the study level. Copyright © 2012 John Wiley & Sons, Ltd. PMID:22825835

  13. Gene expression meta-analysis identifies chromosomal regions involved in ovarian cancer survival

    DEFF Research Database (Denmark)

    Thomassen, Mads; Jochumsen, Kirsten M; Mogensen, Ole

    2009-01-01

    the relation of gene expression and chromosomal position to identify chromosomal regions of importance for early recurrence of ovarian cancer. By use of *Gene Set Enrichment Analysis*, we have ranked chromosomal regions according to their association to survival. Over-representation analysis including 1...... using death (P = 0.015) and recurrence (P = 0.002) as outcome. The combined mutation score is strongly associated to upregulation of several growth factor pathways....

  14. Impact of donor-recipient sex match on long-term survival after heart transplantation in children: An analysis of 5797 pediatric heart transplants.

    Science.gov (United States)

    Kemna, Mariska; Albers, Erin; Bradford, Miranda C; Law, Sabrina; Permut, Lester; McMullan, D Mike; Law, Yuk

    2016-03-01

    The effect of donor-recipient sex matching on long-term survival in pediatric heart transplantation is not well known. Adult data have shown worse survival when male recipients receive a sex-mismatched heart, with conflicting results in female recipients. We analyzed 5795 heart transplant recipients ≤ 18 yr in the Scientific Registry of Transplant Recipients (1990-2012). Recipients were stratified based on donor and recipient sex, creating four groups: MM (N = 1888), FM (N = 1384), FF (N = 1082), and MF (N = 1441). Males receiving sex-matched donor hearts had increased unadjusted allograft survival at five yr (73.2 vs. 71%, p = 0.01). However, this survival advantage disappeared with longer follow-up and when adjusted for additional risk factors by multivariable Cox regression analysis. In contrast, for females, receiving a sex-mismatched heart was associated with an 18% higher risk of allograft loss over time compared to receiving a sex-matched heart (HR 1.18, 95% CI: 1.00-1.38) and a 26% higher risk compared to sex-matched male recipients (HR 1.26, 95% CI: 1.10-1.45). Females who receive a heart from a male donor appear to have a distinct long-term survival disadvantage compared to all other groups. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Safety analysis, risk assessment, and risk acceptance criteria

    International Nuclear Information System (INIS)

    Jamali, K.

    1997-01-01

    This paper discusses a number of topics that relate safety analysis as documented in the Department of Energy (DOE) safety analysis reports (SARs), probabilistic risk assessments (PRA) as characterized primarily in the context of the techniques that have assumed some level of formality in commercial nuclear power plant applications, and risk acceptance criteria as an outgrowth of PRA applications. DOE SARs of interest are those that are prepared for DOE facilities under DOE Order 5480.23 and the implementing guidance in DOE STD-3009-94. It must be noted that the primary area of application for DOE STD-3009 is existing DOE facilities and that certain modifications of the STD-3009 approach are necessary in SARs for new facilities. Moreover, it is the hazard analysis (HA) and accident analysis (AA) portions of these SARs that are relevant to the present discussions. Although PRAs can be qualitative in nature, PRA as used in this paper refers more generally to all quantitative risk assessments and their underlying methods. HA as used in this paper refers more generally to all qualitative risk assessments and their underlying methods that have been in use in hazardous facilities other than nuclear power plants. This discussion includes both quantitative and qualitative risk assessment methods. PRA has been used, improved, developed, and refined since the Reactor Safety Study (WASH-1400) was published in 1975 by the Nuclear Regulatory Commission (NRC). Much debate has ensued since WASH-1400 on exactly what the role of PRA should be in plant design, reactor licensing, 'ensuring' plant and process safety, and a large number of other decisions that must be made for potentially hazardous activities. Of particular interest in this area is whether the risks quantified using PRA should be compared with numerical risk acceptance criteria (RACs) to determine whether a facility is 'safe.' Use of RACs requires quantitative estimates of consequence frequency and magnitude

  16. Survival analysis of a treatment data for cancer of the larynx

    International Nuclear Information System (INIS)

    Khan, K.

    2002-01-01

    In this paper a survival analysis of the survival time is done. The Cox regression model is fitted to the survival time with the assumption of proportional hazard. A model is selected after inclusion and exclusion of factors and variables as explanatory variables. The assumption of proportional hazards is tested in the manner suggested by Harrell (1986). The assumption of proportional hazards is supported by these tests. However the plot of Schoenfeld residuals against dose gave a little evidence of non validity of the proportional hazard assumption. The assumption seems to be satisfied for variable time. The martingale residuals suggest no pattern for variable age. The functional form of dose is not linear. Hence the quadratic dose is used as an explanatory variable. A comparison of logistic regression analysis and survival analysis is also made in this paper. It can be concluded that Cox proportional hazards model is a better model than the logistic model as it is more parsimonious and utilizes more information. (author)

  17. Nonparametric Bayesian inference for mean residual life functions in survival analysis.

    Science.gov (United States)

    Poynor, Valerie; Kottas, Athanasios

    2018-01-19

    Modeling and inference for survival analysis problems typically revolves around different functions related to the survival distribution. Here, we focus on the mean residual life (MRL) function, which provides the expected remaining lifetime given that a subject has survived (i.e. is event-free) up to a particular time. This function is of direct interest in reliability, medical, and actuarial fields. In addition to its practical interpretation, the MRL function characterizes the survival distribution. We develop general Bayesian nonparametric inference for MRL functions built from a Dirichlet process mixture model for the associated survival distribution. The resulting model for the MRL function admits a representation as a mixture of the kernel MRL functions with time-dependent mixture weights. This model structure allows for a wide range of shapes for the MRL function. Particular emphasis is placed on the selection of the mixture kernel, taken to be a gamma distribution, to obtain desirable properties for the MRL function arising from the mixture model. The inference method is illustrated with a data set of two experimental groups and a data set involving right censoring. The supplementary material available at Biostatistics online provides further results on empirical performance of the model, using simulated data examples. © The Author 2018. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Survival Prediction in Pancreatic Ductal Adenocarcinoma by Quantitative Computed Tomography Image Analysis.

    Science.gov (United States)

    Attiyeh, Marc A; Chakraborty, Jayasree; Doussot, Alexandre; Langdon-Embry, Liana; Mainarich, Shiana; Gönen, Mithat; Balachandran, Vinod P; D'Angelica, Michael I; DeMatteo, Ronald P; Jarnagin, William R; Kingham, T Peter; Allen, Peter J; Simpson, Amber L; Do, Richard K

    2018-04-01

    Pancreatic cancer is a highly lethal cancer with no established a priori markers of survival. Existing nomograms rely mainly on post-resection data and are of limited utility in directing surgical management. This study investigated the use of quantitative computed tomography (CT) features to preoperatively assess survival for pancreatic ductal adenocarcinoma (PDAC) patients. A prospectively maintained database identified consecutive chemotherapy-naive patients with CT angiography and resected PDAC between 2009 and 2012. Variation in CT enhancement patterns was extracted from the tumor region using texture analysis, a quantitative image analysis tool previously described in the literature. Two continuous survival models were constructed, with 70% of the data (training set) using Cox regression, first based only on preoperative serum cancer antigen (CA) 19-9 levels and image features (model A), and then on CA19-9, image features, and the Brennan score (composite pathology score; model B). The remaining 30% of the data (test set) were reserved for independent validation. A total of 161 patients were included in the analysis. Training and test sets contained 113 and 48 patients, respectively. Quantitative image features combined with CA19-9 achieved a c-index of 0.69 [integrated Brier score (IBS) 0.224] on the test data, while combining CA19-9, imaging, and the Brennan score achieved a c-index of 0.74 (IBS 0.200) on the test data. We present two continuous survival prediction models for resected PDAC patients. Quantitative analysis of CT texture features is associated with overall survival. Further work includes applying the model to an external dataset to increase the sample size for training and to determine its applicability.

  19. Marital status independently predicts testis cancer survival--an analysis of the SEER database.

    Science.gov (United States)

    Abern, Michael R; Dude, Annie M; Coogan, Christopher L

    2012-01-01

    Previous reports have shown that married men with malignancies have improved 10-year survival over unmarried men. We sought to investigate the effect of marital status on 10-year survival in a U.S. population-based cohort of men with testis cancer. We examined 30,789 cases of testis cancer reported to the Surveillance, Epidemiology, and End Results (SEER 17) database between 1973 and 2005. All staging were converted to the 1997 AJCC TNM system. Patients less than 18 years of age at time of diagnosis were excluded. A subgroup analysis of patients with stages I or II non-seminomatous germ cell tumors (NSGCT) was performed. Univariate analysis using t-tests and χ(2) tests compared characteristics of patients separated by marital status. Multivariate analysis was performed using a Cox proportional hazard model to generate Kaplan-Meier survival curves, with all-cause and cancer-specific mortality as the primary endpoints. 20,245 cases met the inclusion criteria. Married men were more likely to be older (38.9 vs. 31.4 years), Caucasian (94.4% vs. 92.1%), stage I (73.1% vs. 61.4%), and have seminoma as the tumor histology (57.3% vs. 43.4%). On multivariate analysis, married status (HR 0.58, P married status (HR 0.60, P married and unmarried men (44.8% vs. 43.4%, P = 0.33). Marital status is an independent predictor of improved overall and cancer-specific survival in men with testis cancer. In men with stages I or II NSGCT, RPLND is an additional predictor of improved overall survival. Marital status does not appear to influence whether men undergo RPLND. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Genetic polymorphisms in the microRNA binding-sites of the thymidylate synthase gene predict risk and survival in gastric cancer.

    Science.gov (United States)

    Shen, Rong; Liu, Hongliang; Wen, Juyi; Liu, Zhensheng; Wang, Li-E; Wang, Qiming; Tan, Dongfeng; Ajani, Jaffer A; Wei, Qingyi

    2015-09-01

    Thymidylate synthase (TYMS) plays a crucial role in folate metabolism as well as DNA synthesis and repair. We hypothesized that functional polymorphisms in the 3' UTR of TYMS are associated with gastric cancer risk and survival. In the present study, we tested our hypothesis by genotyping three potentially functional (at miRNA binding sites) TYMS SNPs (rs16430 6bp del/ins, rs2790 A>G and rs1059394 C>T) in 379 gastric cancer patients and 431 cancer-free controls. Compared with the rs16430 6bp/6bp + 6bp/0bp genotypes, the 0bp/0bp genotype was associated with significantly increased gastric cancer risk (adjusted OR = 1.72, 95% CI = 1.15-2.58). Similarly, rs2790 GG and rs1059394 TT genotypes were also associated with significantly increased risk (adjusted OR = 2.52, 95% CI = 1.25-5.10 and adjusted OR = 1.57, 95% CI = 1.04-2.35, respectively), compared with AA + AG and CC + CT genotypes, respectively. In the haplotype analysis, the T-G-0bp haplotype was associated with significantly increased gastric cancer risk, compared with the C-A-6bp haplotype (adjusted OR = 1.34, 95% CI = 1.05-1.72). Survival analysis revealed that rs16430 0bp/0bp and rs1059394 TT genotypes were also associated with poor survival in gastric cancer patients who received chemotherapy treatment (adjusted HR = 1.61, 95% CI = 1.05-2.48 and adjusted HR = 1.59, 95% CI = 1.02-2.48, respectively). These results suggest that these three variants in the miRNA binding sites of TYMS may be associated with cancer risk and survival of gastric cancer patients. Larger population studies are warranted to verify these findings. © 2014 Wiley Periodicals, Inc.

  1. Relationships between mastitis and functional longevity in Danish Black and White dairy cattle estimated using survival analysis.

    Science.gov (United States)

    Neerhof, H J; Madsen, P; Ducrocq, V P; Vollema, A R; Jensen, J; Korsgaard, I R

    2000-05-01

    The relationship between mastitis and functional longevity was assessed with survival analysis on data of Danish Black and White dairy cows. Different methods of including the effect of mastitis treatment on the culling decision by a farmer in the model were compared. The model in which mastitis treatment was assumed to have an effect on functional longevity until the end of the lactation had the highest likelihood, and the model in which mastitis treatment had an effect for only a short period had the lowest likelihood. A cow with mastitis had 1.69 times greater risk of being culled than did a healthy herdmate with all other effects being the same. A model without mastitis treatment was used to predict transmitting abilities of bulls for risk of being culled, based on longevity records of their daughters, and was expressed in terms of risk of being culled. The correlation between the risk of being culled and the national evaluations of the bulls for mastitis resistance was approximately -0.4, indicating that resistance against mastitis was genetically correlated with a lower risk of being culled and, thus, a longer functional length of productive life.

  2. GIS risk analysis of hazardous materials transport

    International Nuclear Information System (INIS)

    Anders, C.; Olsten, J.

    1991-01-01

    The Geographic Information System (GIS) was used to assess the risks and vulnerability of transporting hazardous materials and wastes (such as gasoline, explosives, poisons, etc) on the Arizona highway system. This paper discusses the methodology that was utilized, and the application of GIS systems to risk analysis problems

  3. No survival difference after successful {sup 131}I ablation between patients with initially low-risk and high-risk differentiated thyroid cancer

    Energy Technology Data Exchange (ETDEWEB)

    Verburg, Frederik Anton [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); University Medical Center Utrecht, Department of Radiology and Nuclear Medicine, Utrecht (Netherlands); Stokkel, Marcel P.M.; Verkooijen, Robbert B.T. [Leiden University Medical Center, Department of Radiology, Division of Nuclear Medicine, Leiden (Netherlands); Dueren, Christian; Reiners, Christoph [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Maeder, Uwe [University of Wuerzburg, Comprehensive Cancer Center, Wuerzburg (Germany); Isselt, Johannes W. van [University Medical Center Utrecht, Department of Radiology and Nuclear Medicine, Utrecht (Netherlands); Marlowe, Robert J. [Spencer-Fontayne Corporation, Jersey City, NJ (United States); Smit, Johannes W. [Leiden University Medical Center, Department of Endocrinology, Leiden (Netherlands); Luster, Markus [University of Ulm, Department of Nuclear Medicine, Ulm (Germany)

    2010-02-15

    To compare disease-specific survival and recurrence-free survival (RFS) after successful {sup 131}I ablation in patients with differentiated thyroid carcinoma (DTC) between those defined before ablation as low-risk and those defined as high-risk according to the European Thyroid Association 2006 consensus statement. Retrospective data from three university hospitals were pooled. Of 2009 consecutive patients receiving ablation, 509 were identified as successfully ablated based on both undetectable stimulated serum thyroglobulin in the absence of antithyroglobulin antibodies and a negative diagnostic whole-body scan in a follow-up examination conducted 8.1{+-}4.6 months after ablation. Of these 509 patients, 169 were defined as high-risk. After a mean follow-up of 81{+-}64 months (range 4-306 months), only three patients had died of DTC, rendering assessment of disease-specific survival differences impossible. Of the 509 patients, 12 (2.4%) developed a recurrence a mean 35 months (range 12-59 months) after ablation. RFS for the duration of follow-up was 96.6% according to the Kaplan-Meier method. RFS did not differ between high-risk and low-risk patients (p=0.68). RFS differed slightly but significantly between those with papillary and those with follicular thyroid carcinoma (p=0.03) and between those aged {<=}45 years those aged >45 years at diagnosis (p=0.018). After (near) total thyroidectomy and successful {sup 131}I ablation, RFS does not differ between patients classified as high-risk and those classified as low-risk based on TNM stage at diagnosis. Consequently, the follow-up protocol should be determined on the basis of the result of initial treatment rather than on the initial tumour classification. (orig.)

  4. Survival Bias When Assessing Risk Factors for Age-Related Macular Degeneration: A Tutorial with Application to the Exposure of Smoking.

    Science.gov (United States)

    McGuinness, Myra B; Karahalios, Amalia; Kasza, Jessica; Guymer, Robyn H; Finger, Robert P; Simpson, Julie A

    2017-08-01

    We illustrate the effect of survival bias when investigating risk factors for eye disease in elderly populations for whom death is a competing risk. Our investigation focuses on the relationship between smoking and late age-related macular degeneration (AMD) in an observational study impacted by censoring due to death. Statistical methodology to calculate the survivor average causal effect (SACE) as a sensitivity analysis is described, including example statistical computing code for Stata and R. To demonstrate this method, we examine the causal effect of smoking history at baseline (1990-1994) on the presence of late AMD at the third study wave (2003-2007) using data from the Melbourne Collaborative Cohort Study. Of the 40,506 participants eligible for inclusion, 38,092 (94%) survived until the start of the third study wave, 20,752 (51%) were graded for AMD (60% female, aged 47-85 years, mean 65 ± 8.7 years). Late AMD was detected in 122 participants. Logistic regression showed strong evidence of an increased risk of late AMD for current smokers compared to non-smokers (adjusted naïve odds ratio 2.99, 95% confidence interval, CI, 1.74-5.13). Among participants expected to be alive at the start of follow-up regardless of their smoking status, the estimated SACE odds ratio comparing current smokers to non-smokers was at least 3.42 (95% CI 1.57-5.15). Survival bias can attenuate associations between harmful exposures and diseases of aging. Estimation of the SACE using a sensitivity analysis approach should be considered when conducting epidemiological research within elderly populations.

  5. Dealing with phenomenological uncertainty in risk analysis

    International Nuclear Information System (INIS)

    Theofanous, T.G.

    1994-01-01

    The Risk-Oriented Accident Analysis Methodology (ROAAM) is summarized and developed further towards a formal definition. The key ideas behind the methodology and these more formal aspects are also presented and discussed

  6. Risk and safety analysis of nuclear systems

    National Research Council Canada - National Science Library

    Lee, John C; McCormick, Norman J

    2011-01-01

    .... The first half of the book covers the principles of risk analysis, the techniques used to develop and update a reliability data base, the reliability of multi-component systems, Markov methods used...

  7. Risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Koelzer, W.

    1983-01-01

    The German risk analysis program for nuclear power plants aiming at the man and the environment is presented. An accident consequence model to calculate the radiological impact and the potential health effects is described. (E.G.) [pt

  8. Validation of Progression‐Free Survival as a Surrogate Endpoint for Overall Survival in Malignant Mesothelioma: Analysis of Cancer and Leukemia Group B and North Central Cancer Treatment Group (Alliance) Trials

    Science.gov (United States)

    Wang, Xiaoyi; Hodgson, Lydia; George, Stephen L.; Sargent, Daniel J.; Foster, Nate R.; Ganti, Apar Kishor; Stinchcombe, Thomas E.; Crawford, Jeffrey; Kratzke, Robert; Adjei, Alex A.; Kindler, Hedy L.; Vokes, Everett E.; Pang, Herbert

    2017-01-01

    Abstract Purpose. The aim of this study was to investigate whether progression‐free survival (PFS) can be considered a surrogate endpoint for overall survival (OS) in malignant mesothelioma. Materials and Methods. Individual data were collected from 15 Cancer and Leukemia Group B (615 patients) and 2 North Central Cancer Treatment Group (101 patients) phase II trials. The effects of 5 risk factors for OS and PFS, including age, histology, performance status (PS), white blood cell count, and European Organisation for Research and Treatment of Cancer (EORTC) risk score, were used in the analysis. Individual‐level surrogacy was assessed by Kendall's tau through a Clayton bivariate Copula survival (CBCS) model. Summary‐level surrogacy was evaluated via the association between logarithms of the hazard ratio (log HR)—log HROS and log HRPFS—measured in R2 from a weighted least‐square (WLS) regression model and the CBCS model. Results. The median PFS for all patients was 3.0 months (95% confidence interval [CI], 2.8–3.5 months) and the median OS was 7.2 months (95% CI, 6.5–8.0 months). Moderate correlations between PFS and OS were observed across all risk factors at the individual level, with Kendall's tau ranging from 0.46 to 0.47. The summary‐level surrogacy varied among risk factors. The Copula R2 ranged from 0.51 for PS to 0.78 for histology. The WLS R2 ranged from 0.26 for EORTC and PS to 0.67 for age. Conclusions. The analyses demonstrated low to moderate individual‐level surrogacy between PFS and OS. At the summary level, the surrogacy between PFS and OS varied significantly across different risk factors. With a short postprogression survival and a moderate correlation between PFS and OS, there is no evidence that PFS is a valid surrogate endpoint for OS in malignant mesothelioma. Implications for Practice. For better disease management and for more efficient clinical trial designs, it is important to know if progression‐free survival (PFS) is

  9. Survival analysis of patients with uveal melanoma after organ preserving and liquidation treatment

    Directory of Open Access Journals (Sweden)

    E. E. Grishina

    2018-01-01

    Full Text Available Rationale: Uveal melanoma is the most common primary malignancy of the eye.Aim: To evaluate survival in patients with uveal melanoma stratified according to the type of treatment and to identify factors significantly associated with their survival.Materials and methods: The study was performed on the data extracted from medical files and follow-up forms of patients with uveal melanoma seen in the Ophthalmological Clinical Hospital of the Department of Healthcare, Moscow, from 1977 to 2012. Analysis of survival was used to assess the life longevity of patients with uveal melanoma. The analysis was censored at January 2013, when vital status (dead or alive of all patients was assessed. The factors included into the study analysis, were those taken from the follow-up forms. The incidence of uveal melanoma in Moscow (2012 was 0.9 per 100,000 of the population, whereas its prevalence was 11.1 per 100,000.Results: 698 patients with uveal melanoma were included into the study, among them 260 (37% men (aged from 19 to 87 years, median age 60 years and 438 (63% women (aged from 18 to 93 years, median age 63 years; therefore, the proportion of women under the follow-up monitoring was by 26% higher than that of men. The liquidation treatment (mostly enucleation was performed in 358 (51% of the patients, whereas the organ preserving treatment in 340 (49%. At 5, 7, and 10 years of the follow-up, the disease-specific survival of patients with uveal melanoma after the organ preserving treatment (median survival has not been reached and after the liquidation treatment (median, 88 months were 89 ± 2, 83 ± 3, and 75 ± 4% versus 63 ± 3, 52 ± 4, and 47 ± 5%, respectively (р = 0.001. Overall survival and disease-specific survival of the patients after the liquidation treatment were significantly lower than in the patients after the organ-preserving treatment. According to multiple regression analysis, this was associated not with the type of

  10. Gender, Race, and Survival: A Study in Non-Small-Cell Lung Cancer Brain Metastases Patients Utilizing the Radiation Therapy Oncology Group Recursive Partitioning Analysis Classification

    International Nuclear Information System (INIS)

    Videtic, Gregory M.M.; Reddy, Chandana A.; Chao, Samuel T.; Rice, Thomas W.; Adelstein, David J.; Barnett, Gene H.; Mekhail, Tarek M.; Vogelbaum, Michael A.; Suh, John H.

    2009-01-01

    Purpose: To explore whether gender and race influence survival in non-small-cell lung cancer (NSCLC) in patients with brain metastases, using our large single-institution brain tumor database and the Radiation Therapy Oncology Group recursive partitioning analysis (RPA) brain metastases classification. Methods and materials: A retrospective review of a single-institution brain metastasis database for the interval January 1982 to September 2004 yielded 835 NSCLC patients with brain metastases for analysis. Patient subsets based on combinations of gender, race, and RPA class were then analyzed for survival differences. Results: Median follow-up was 5.4 months (range, 0-122.9 months). There were 485 male patients (M) (58.4%) and 346 female patients (F) (41.6%). Of the 828 evaluable patients (99%), 143 (17%) were black/African American (B) and 685 (83%) were white/Caucasian (W). Median survival time (MST) from time of brain metastasis diagnosis for all patients was 5.8 months. Median survival time by gender (F vs. M) and race (W vs. B) was 6.3 months vs. 5.5 months (p = 0.013) and 6.0 months vs. 5.2 months (p = 0.08), respectively. For patients stratified by RPA class, gender, and race, MST significantly favored BFs over BMs in Class II: 11.2 months vs. 4.6 months (p = 0.021). On multivariable analysis, significant variables were gender (p = 0.041, relative risk [RR] 0.83) and RPA class (p < 0.0001, RR 0.28 for I vs. III; p < 0.0001, RR 0.51 for II vs. III) but not race. Conclusions: Gender significantly influences NSCLC brain metastasis survival. Race trended to significance in overall survival but was not significant on multivariable analysis. Multivariable analysis identified gender and RPA classification as significant variables with respect to survival.

  11. ATM and p53 combined analysis predicts survival in glioblastoma multiforme patients: A clinicopathologic study.

    Science.gov (United States)

    Romano, Francesco Jacopo; Guadagno, Elia; Solari, Domenico; Borrelli, Giorgio; Pignatiello, Sara; Cappabianca, Paolo; Del Basso De Caro, Marialaura

    2018-06-01

    Glioblastoma is one of the most malignant cancers, with a distinguishing dismal prognosis: surgery followed by chemo- and radiotherapy represents the current standard of care, and chemo- and radioresistance underlie disease recurrence and short overall survival of patients suffering from this malignancy. ATM is a kinase activated by autophosphorylation upon DNA doublestrand breaks arising from errors during replication, byproducts of metabolism, chemotherapy or ionizing radiations; TP53 is one of the most popular tumor suppressor, with a preeminent role in DNA damage response and repair. To study the effects of the immunohistochemical expression of p-ATM and p53 in glioblastoma patients, 21 cases were retrospectively examined. In normal brain tissue, p-ATM was expressed only in neurons; conversely, in tumors cells, the protein showed a variable cytoplasmic expression (score: +,++,+++), with being completely undetectable in three cases. Statistical analysis revealed that high p-ATM score (++/+++) strongly correlated to shorter survival (P = 0.022). No difference in overall survival was registered between p53 normally expressed (NE) and overexpressed (OE) glioblastoma patients (P = 0.669). Survival analysis performed on the results from combined assessment of the two proteins showed that patients with NE p53 /low pATM score had longer overall survival than the NE p53/ high pATM score counterpart. Cox-regression analysis confirmed this finding (HR = 0.025; CI 95% = 0.002-0.284; P = 0.003). Our study outlined the immunohistochemical expression of p-ATM/p53 in glioblastomas and provided data on their possible prognostic/predictive of response role. A "non-oncogene addiction" to ATM for NEp53 glioblastoma could be postulated, strengthening the rationale for development of ATM inhibiting drugs. © 2018 Wiley Periodicals, Inc.

  12. Identification of subgroups by risk of graft failure after paediatric renal transplantation: application of survival tree models on the ESPN/ERA-EDTA Registry.

    Science.gov (United States)

    Lofaro, Danilo; Jager, Kitty J; Abu-Hanna, Ameen; Groothoff, Jaap W; Arikoski, Pekka; Hoecker, Britta; Roussey-Kesler, Gwenaelle; Spasojević, Brankica; Verrina, Enrico; Schaefer, Franz; van Stralen, Karlijn J

    2016-02-01

    Identification of patient groups by risk of renal graft loss might be helpful for accurate patient counselling and clinical decision-making. Survival tree models are an alternative statistical approach to identify subgroups, offering cut-off points for covariates and an easy-to-interpret representation. Within the European Society of Pediatric Nephrology/European Renal Association-European Dialysis and Transplant Association (ESPN/ERA-EDTA) Registry data we identified paediatric patient groups with specific profiles for 5-year renal graft survival. Two analyses were performed, including (i) parameters known at time of transplantation and (ii) additional clinical measurements obtained early after transplantation. The identified subgroups were added as covariates in two survival models. The prognostic performance of the models was tested and compared with conventional Cox regression analyses. The first analysis included 5275 paediatric renal transplants. The best 5-year graft survival (90.4%) was found among patients who received a renal graft as a pre-emptive transplantation or after short-term dialysis (2.2 years). The Cox model including both pre-transplant factors and tree subgroups had a significantly better predictive performance than conventional Cox regression (P 30 mL/min/1.73 m(2) and dialysis 20 months). Also in this case combining tree findings and clinical factors improved the predictive performance as compared with conventional Cox model models (P tree model to be an accurate and attractive tool to predict graft failure for patients with specific characteristics. This may aid the evaluation of individual graft prognosis and thereby the design of measures to improve graft survival in the poor prognosis groups. © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  13. Androgen Deprivation Therapy Does Not Impact Cause-Specific or Overall Survival in High-Risk Prostate Cancer Managed With Brachytherapy and Supplemental External Beam

    International Nuclear Information System (INIS)

    Merrick, Gregory S.; Butler, Wayne M.; Wallner, Kent E.; Galbreath, Robert W.; Allen, Zachariah A.; Adamovich, Edward; Lief, Jonathan

    2007-01-01

    Purpose: To determine cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) in high-risk prostate cancer patients undergoing brachytherapy with or without supplemental therapies. Methods and Materials: Between April 1995 and July 2002, 204 patients with high-risk prostate cancer (Gleason score ≥8 or prostate-specific antigen [PSA] >20 ng/mL or clinical stage ≥T2c) underwent brachytherapy. Median follow-up was 7.0 years. The bPFS was defined by a PSA ≤0.40 ng/mL after nadir. Multiple clinical, treatment, and dosimetric parameters were evaluated for the impact on survival. Results: The 10-year CSS, bPFS, and OS were 88.9%, 86.6%, and 68.6%, respectively. A statistically significant difference in bPFS was discerned between hormone naive, ADT ≤6 months, and ADT >6 month cohorts (79.7% vs. 95.% vs. 89.9%, p = 0.032). Androgen deprivation therapy (ADT) did not impact CSS or OS. For bPFS patients, the median posttreatment PSA was <0.04 ng/mL. A Cox linear regression analysis demonstrated that Gleason score was the best predictor of CSS, whereas percent positive biopsies and duration of ADT best predicted for bPFS. The OS was best predicted by Gleason score and diabetes. Thirty-eight patients have died, with 26 of the deaths from cardiovascular/pulmonary disease or second malignancy. Eleven patients have died of metastatic prostate cancer. Conclusions: The ADT improved 10-year bPFS without statistical impact on CSS or OS. Death as a result of cardiovascular/pulmonary disease and second malignancies were more than twice as common as prostate cancer deaths. Strategies to improve cardiovascular health should positively impact OS

  14. Probabilistic risk analysis in chemical engineering

    International Nuclear Information System (INIS)

    Schmalz, F.

    1991-01-01

    In risk analysis in the chemical industry, recognising potential risks is considered more important than assessing their quantitative extent. Even in assessing risks, emphasis is not on the probability involved but on the possible extent. Qualitative assessment has proved valuable here. Probabilistic methods are used in individual cases where the wide implications make it essential to be able to assess the reliability of safety precautions. In this case, assessment therefore centres on the reliability of technical systems and not on the extent of a chemical risk. 7 figs

  15. Modelling lecturer performance index of private university in Tulungagung by using survival analysis with multivariate adaptive regression spline

    Science.gov (United States)

    Hasyim, M.; Prastyo, D. D.

    2018-03-01

    Survival analysis performs relationship between independent variables and survival time as dependent variable. In fact, not all survival data can be recorded completely by any reasons. In such situation, the data is called censored data. Moreover, several model for survival analysis requires assumptions. One of the approaches in survival analysis is nonparametric that gives more relax assumption. In this research, the nonparametric approach that is employed is Multivariate Regression Adaptive Spline (MARS). This study is aimed to measure the performance of private university’s lecturer. The survival time in this study is duration needed by lecturer to obtain their professional certificate. The results show that research activities is a significant factor along with developing courses material, good publication in international or national journal, and activities in research collaboration.

  16. Trends in Testicular Cancer Survival: A Large Population-based Analysis.

    Science.gov (United States)

    Sui, Wilson; Morrow, David C; Bermejo, Carlos E; Hellenthal, Nicholas J

    2015-06-01

    To determine whether discrepancies in testicular cancer outcomes between Caucasians and non-Caucasians are changing over time. Although testicular cancer is more common in Caucasians, studies have shown that other races have worse outcomes. Using the Surveillance, Epidemiology, and End Results registry, we identified 29,803 patients diagnosed with histologically confirmed testicular cancer between 1983 and 2011. Of these, 12,650 patients (42%) had 10-year follow-up data. We stratified the patients by age group, stage, race, and year of diagnosis and assessed 10-year overall and cancer-specific survival in each cohort. Cox proportional hazard models were used to determine the relative contributions of each stratum to cancer-specific survival. Predicted overall 10-year survival of Caucasian patients with testicular cancer increased slightly from 88% to 89% over the period studied, whereas predicted cancer-specific 10-year survival dropped slightly from 94% to 93%. In contrast, non-Caucasian men demonstrated larger changes in 10-year overall (84%-86%) and cancer-specific (88%-91%) survival. On univariate analysis, race was significantly associated with testicular cancer death, with non-Caucasian men being 1.69 times more likely to die of testicular cancer than Caucasians (hazard ratio, 1.33-2.16; 95% confidence interval, testicular cancer. These data show a convergence in cancer-specific survival between racial groups over time, suggesting that diagnostic and treatment discrepancies may be improving for non-Caucasians. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Survival analysis of female dogs with mammary tumors after mastectomy: epidemiological, clinical and morphological aspects

    Directory of Open Access Journals (Sweden)

    Maria Luíza de M. Dias

    2016-03-01

    Full Text Available Abstract: Mammary gland tumors are the most common type of tumors in bitches but research on survival time after diagnosis is scarce. The purpose of this study was to investigate the relationship between survival time after mastectomy and a number of clinical and morphological variables. Data was collected retrospectively on bitches with mammary tumors seen at the Small Animal Surgery Clinic Service at the University of Brasília. All subjects had undergone mastectomy. Survival analysis was conducted using Cox's proportional hazard method. Of the 139 subjects analyzed, 68 died and 71 survived until the end of the study (64 months. Mean age was 11.76 years (SD=2.71, 53.84% were small dogs. 76.92% of the tumors were malignant, and 65.73% had both thoracic and inguinal glands affected. Survival time in months was associated with age (hazard rate ratios [HRR] =1.23, p-value =1.4x10-4, animal size (HRR between giant and small animals =2.61, p-value =0.02, nodule size (HRR =1.09, p-value =0.03, histological type (HRR between solid carcinoma and carcinoma in a mixed tumor =2.40, p-value =0.02, time between diagnosis and surgery (TDS, with HRR =1.21, p-value =2.7x10-15, and the interaction TDS*follow-up time (HRR =0.98, p-value =1.6x10-11. The present study is one of the few on the subject matter. Several important covariates were evaluated and age, animal size, nodule size, histological type, TDS and TDS*follow up time were identified as significantly associated to survival time.

  18. Treatment of unresectable hepatocellular carcinoma with intrahepatic yttrium 90 microspheres: a risk-stratification analysis.

    Science.gov (United States)

    Goin, James E; Salem, Riad; Carr, Brian I; Dancey, Janet E; Soulen, Michael C; Geschwind, Jean-Francois H; Goin, Kathleen; Van Buskirk, Mark; Thurston, Kenneth

    2005-02-01

    To present the findings of a risk-stratification survival analysis with use of data collected on a heterogeneous group of patients with hepatocellular carcinoma (HCC) treated with TheraSphere. Baseline, treatment, and follow-up data were collected and analyzed from 121 TheraSphere-treated patients. Survival analyses were performed to identify those variables most strongly associated with 3-month mortality. The presence of any of the identified risk variables resulted in the assignment of a patient to the high-risk category. Five liver reserve and two non-liver reserve variables were identified and used to stratify patients into low- or high-risk groups. Sixteen of the 33 patients assigned to the high-risk group (49%) did not survive the first 3 months after treatment, compared with six of the 88 patients assigned to the low-risk group (7%; Fisher exact test, P TheraSpheres should be evaluated for the presence of the risk variables described herein. The absence of these variables is predictive of improved survival (median of 466 days) compared with patients at high risk (median of 108 days).

  19. Outcome predictors in the management of intramedullary classic ependymoma: An integrative survival analysis.

    Science.gov (United States)

    Wang, Yinqing; Cai, Ranze; Wang, Rui; Wang, Chunhua; Chen, Chunmei

    2018-06-01

    This is a retrospective study.The aim of this study was to illustrate the survival outcomes of patients with classic ependymoma (CE) and identify potential prognostic factors.CE is the most common category of spinal ependymomas, but few published studies have discussed predictors of the survival outcome.A Boolean search of the PubMed, Embase, and OVID databases was conducted by 2 investigators independently. The objects were intramedullary grade II ependymoma according to 2007 WHO classification. Univariate Kaplan-Meier analysis and Log-Rank tests were performed to identify variables associated with progression-free survival (PFS) or overall survival (OS). Multivariate Cox regression was performed to assess hazard ratios (HRs) with 95% confidence intervals (95% CIs). Statistical analysis was performed by SPSS version 23.0 (IBM Corp.) with statistical significance defined as P analysis showed that patients who had undergone total resection (TR) had better PFS and OS than those with subtotal resection (STR) and biopsy (P = .002, P = .004, respectively). Within either univariate or multivariate analysis (P = .000, P = .07, respectively), histological type was an independent prognostic factor for PFS of CE [papillary type: HR 0.002, 95% CI (0.000-0.073), P = .001, tanycytic type: HR 0.010, 95% CI (0.000-0.218), P = .003].It was the first integrative analysis of CE to elucidate the correlation between kinds of factors and prognostic outcomes. Definite histological type and safely TR were foundation of CE's management. 4.

  20. Development and external validation of a risk-prediction model to predict 5-year overall survival in advanced larynx cancer.

    Science.gov (United States)

    Petersen, Japke F; Stuiver, Martijn M; Timmermans, Adriana J; Chen, Amy; Zhang, Hongzhen; O'Neill, James P; Deady, Sandra; Vander Poorten, Vincent; Meulemans, Jeroen; Wennerberg, Johan; Skroder, Carl; Day, Andrew T; Koch, Wayne; van den Brekel, Michiel W M

    2018-05-01

    TNM-classification inadequately estimates patient-specific overall survival (OS). We aimed to improve this by developing a risk-prediction model for patients with advanced larynx cancer. Cohort study. We developed a risk prediction model to estimate the 5-year OS rate based on a cohort of 3,442 patients with T3T4N0N+M0 larynx cancer. The model was internally validated using bootstrapping samples and externally validated on patient data from five external centers (n = 770). The main outcome was performance of the model as tested by discrimination, calibration, and the ability to distinguish risk groups based on tertiles from the derivation dataset. The model performance was compared to a model based on T and N classification only. We included age, gender, T and N classification, and subsite as prognostic variables in the standard model. After external validation, the standard model had a significantly better fit than a model based on T and N classification alone (C statistic, 0.59 vs. 0.55, P statistic to 0.68. A risk prediction model for patients with advanced larynx cancer, consisting of readily available clinical variables, gives more accurate estimations of the estimated 5-year survival rate when compared to a model based on T and N classification alone. 2c. Laryngoscope, 128:1140-1145, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  1. Reliability and risk analysis methods research plan

    International Nuclear Information System (INIS)

    1984-10-01

    This document presents a plan for reliability and risk analysis methods research to be performed mainly by the Reactor Risk Branch (RRB), Division of Risk Analysis and Operations (DRAO), Office of Nuclear Regulatory Research. It includes those activities of other DRAO branches which are very closely related to those of the RRB. Related or interfacing programs of other divisions, offices and organizations are merely indicated. The primary use of this document is envisioned as an NRC working document, covering about a 3-year period, to foster better coordination in reliability and risk analysis methods development between the offices of Nuclear Regulatory Research and Nuclear Reactor Regulation. It will also serve as an information source for contractors and others to more clearly understand the objectives, needs, programmatic activities and interfaces together with the overall logical structure of the program

  2. Gender Analysis of Risk in Innovation System

    DEFF Research Database (Denmark)

    Ayinde, Ope; Muchie, Mammo; Abaniyan, E. O.

    2011-01-01

    the new maize variety. The analytical tools used include descriptive statistics, regression model; risk utility functions and risk parameter analysis. The result showed that invasion by animals, disease and pest, lack of access to credit wind and price fluctuation were the major risk facing the maize......This study analyzed risk by gender in innovation in Kwara state, Nigeria, using downy mildew resistant maize production as case study. The study employed primary and secondary data. The primary data were collected from well-structured questionnaires administered to both male and female producing...... producers in the area in the usage of the new innovation. The study also revealed that male producers were willing to take risk in the new maize variety production than the female, while the females were more indifferent to the risk involved in the new maize production variety than males. None...

  3. Intentional risk management through complex networks analysis

    CERN Document Server

    Chapela, Victor; Moral, Santiago; Romance, Miguel

    2015-01-01

    This book combines game theory and complex networks to examine intentional technological risk through modeling. As information security risks are in constant evolution,  the methodologies and tools to manage them must evolve to an ever-changing environment. A formal global methodology is explained  in this book, which is able to analyze risks in cyber security based on complex network models and ideas extracted from the Nash equilibrium. A risk management methodology for IT critical infrastructures is introduced which provides guidance and analysis on decision making models and real situations. This model manages the risk of succumbing to a digital attack and assesses an attack from the following three variables: income obtained, expense needed to carry out an attack, and the potential consequences for an attack. Graduate students and researchers interested in cyber security, complex network applications and intentional risk will find this book useful as it is filled with a number of models, methodologies a...

  4. A hybrid approach of gene sets and single genes for the prediction of survival risks with gene expression data.

    Science.gov (United States)

    Seok, Junhee; Davis, Ronald W; Xiao, Wenzhong

    2015-01-01

    Accumulated biological knowledge is often encoded as gene sets, collections of genes associated with similar biological functions or pathways. The use of gene sets in the analyses of high-throughput gene expression data has been intensively studied and applied in clinical research. However, the main interest remains in finding modules of biological knowledge, or corresponding gene sets, significantly associated with disease conditions. Risk prediction from censored survival times using gene sets hasn't been well studied. In this work, we propose a hybrid method that uses both single gene and gene set information together to predict patient survival risks from gene expression profiles. In the proposed method, gene sets provide context-level information that is poorly reflected by single genes. Complementarily, single genes help to supplement incomplete information of gene sets due to our imperfect biomedical knowledge. Through the tests over multiple data sets of cancer and trauma injury, the proposed method showed robust and improved performance compared with the conventional approaches with only single genes or gene sets solely. Additionally, we examined the prediction result in the trauma injury data, and showed that the modules of biological knowledge used in the prediction by the proposed method were highly interpretable in biology. A wide range of survival prediction problems in clinical genomics is expected to benefit from the use of biological knowledge.

  5. Can Diffusion-weighted Magnetic Resonance Imaging Predict Survival in Patients with Cervical Cancer? A Meta-Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yu-Ting, E-mail: wangyuting_330@163.com; Li, Ying-Chun, E-mail: anicespringspring@163.com; Yin, Long-Lin, E-mail: yinlonglin@163.com; Pu, Hong, E-mail: ph196797@163.com

    2016-12-15

    Highlights: • DWI may serve as a prognostic factor in patients with cervical cancer. • Unfavorable DWI results (mostly low ADC) were associated with higher risks of tumor recurrence. • A quantified ADC was shown to be a suitable candidate indicator. - Abstract: Objective: Although diffusion-weighted magnetic resonance imaging (DWI) has been widely used in the diagnosis of cervical cancer, whether it can predict disease recurrence or survival remains inconclusive. This study aimed to systematically evaluate whether DWI can serve as a reliable prognostic predictor in patients with cervical cancer. Methods: PubMed, the MEDLINE database and the Cochrane Library were searched for DWI studies with >12 months of prognostic data in patients with cervical cancer. Endpoints included tumor recurrence and death. Methodological quality was assessed using the Quality in Prognostic Studies (QUIPS) tool. Combined estimates of hazard ratios (HRs) were derived. Results: Nine studies involving a total of 796 patients (mean/median age from 45.0 years to 62.9 years) met the inclusion criteria. Methodological quality was relatively high. Eight of the nine studies employed apparent diffusion coefficient (ADC) as an indicator of DWI results. Using disease-free survival (DFS) as an outcome measure, nine studies yielded a combined HR of 1.55 (95% confidence interval (CI): 1.23–1.95), and seven studies that employed pretreatment DWI yielded a combined HR of 1.50 (95% CI: 1.03–2.19), which indicated that unfavorable DWI results were associated with an approximately 1.50–1.55-fold higher risk of tumor recurrence. The two studies investigating the impact of DWI results on overall survival (OS) reported HRs of 7.20 and 2.17, respectively. Conclusion: DWI may serve as a predictor of tumor recurrence in patients with cervical cancer as showed by meta-analysis, and the quantified ADC as a suitable candidate indicator.

  6. Association of germline variation in CCNE1 and CDK2 with breast cancer risk, progression and survival among Chinese Han women.

    Directory of Open Access Journals (Sweden)

    Ji-Yuan Han

    Full Text Available BACKGROUND: Somatic alterations of cyclin-dependent kinase 2 (CDK2-cyclin E complex have been shown to contribute to breast cancer (BC development and progression. This study aimed to explore the effects of single nucleotide polymorphisms (SNPs in CDK2 and CCNE1 (a gene encoding G1/S specific cyclin E1 protein, formerly called cyclin E on BC risk, progression and survival in a Chinese Han population. METHODOLOGY/PRINCIPAL FINDINGS: We herein genotyped 6 haplotype-tagging SNPs (htSNPs of CCNE1 and 2 htSNPs of CDK2 in 1207 BC cases and 1207 age-matched controls among Chinese Han women, and then reconstructed haplotype blocks according to our genotyping data and linkage disequilibrium status of these htSNPs. For CCNE1, the minor allele homozygotes of three htSNPs were associated with BC risk (rs3218035: adjusted odds ratio [aOR] = 3.35, 95% confidence interval [CI] = 1.69-6.67; rs3218038: aOR = 1.81, 95% CI = 1.22-2.70; rs3218042: aOR = 2.64, 95% CI = 1.31-5.34, and these three loci showed a dose-dependent manner in increasing BC risk (P(trend = 0.0001. Moreover, the 5-SNP haplotype CCGTC, which carried none of minor alleles of the 3 at-risk SNPs, was associated with a favorable event-free survival (hazard ratio [HR] = 0.53, 95% CI = 0.32-0.90. Stratified analysis suggested that the minor-allele homozygote carriers of rs3218038 had a worse event-free survival among patients with aggressive tumours (in tumour size>2 cm group: HR = 2.06, 95% CI = 1.06-3.99; in positive lymph node metastasis group: HR = 2.41, 95% CI = 1.15-5.03; in stage II-IV group: HR = 2.03, 95% CI = 1.09-3.79. For CDK2, no significant association was found. CONCLUSIONS/SIGNIFICANCE: This study indicates that genetic variants in CCNE1 may contribute to BC risk and survival in Chinese Han population. They may become molecular markers for individual evaluation of BC susceptibility and prognosis. Nevertheless, further validation studies are needed.

  7. Tracheostomy mechanical ventilation in patients with amyotrophic lateral sclerosis: clinical features and survival analysis.

    Science.gov (United States)

    Spataro, Rossella; Bono, Valeria; Marchese, Santino; La Bella, Vincenzo

    2012-12-15

    Tracheostomy mechanical ventilation (TMV) is performed in amyotrophic lateral sclerosis (ALS) patients with a respiratory failure or when the non-invasive ventilation (NIV) is no longer effective. We evaluated the clinical characteristics and survival of a cohort of tracheostomized ALS patients, followed in a single ALS Clinical Center. Between 2001 and 2010, 87 out of 279 ALS patients were submitted to TMV. Onset was spinal in 62 and bulbar in 25. After tracheostomy, most patients were followed up through telephone interviews to caregivers. A complete survival analysis could be performed in fifty-two TMV patients. 31.3% ALS patients underwent tracheostomy, with a male prevalence (M/F=1.69) and a median age of 61 years (interquartile range=47-66). After tracheostomy, nearly all patients were under home care. TMV ALS patients were more likely than non-tracheostomized (NT) patients to be implanted with a PEG device, although the bulbar-/spinal-onset ratio did not differ between the two groups. Kaplan-Meyer analysis showed that tracheostomy increases median survival (TMV, 47 months vs NT, 31 months, p=0.008), with the greatest effect in patients younger than 60 at onset (TMV ≤ 60 years, 57.5 months vs NT ≤ 60 years, 38.5 months, p=0.002). TMV is increasingly performed in ALS patients. Nearly all TMV patients live at home and most of them are fed through a PEG device. Survival after tracheostomy is generally increased, with the stronger effect in patients younger than 60. This survival advantage is apparently lost when TMV is performed in patients older than 60. The results of this study might be useful for the decision-making process of patients and their families about this advanced palliative care. Copyright © 2012. Published by Elsevier B.V.

  8. Determinants of malignant pleural mesothelioma survival and burden of disease in France: a national cohort analysis.

    Science.gov (United States)

    Chouaid, Christos; Assié, Jean Baptiste; Andujar, Pascal; Blein, Cecile; Tournier, Charlène; Vainchtock, Alexandre; Scherpereel, Arnaud; Monnet, Isabelle; Pairon, Jean Claude

    2018-04-01

    This study was undertaken to determine the healthcare burden of malignant pleural mesothelioma (MPM) in France and to analyze its associations with socioeconomic deprivation, population density, and management outcomes. A national hospital database was used to extract incident MPM patients in years 2011 and 2012. Cox models were used to analyze 1- and 2-year survival according to sex, age, co-morbidities, management, population-density index, and social deprivation index. The analysis included 1,890 patients (76% men; age: 73.6 ± 10.0 years; 84% with significant co-morbidities; 57% living in urban zones; 53% in highly underprivileged areas). Only 1% underwent curative surgical procedure; 65% received at least one chemotherapy cycle, 72% of them with at least one pemetrexed and/or bevacizumab administration. One- and 2-year survival rates were 64% and 48%, respectively. Median survival was 14.9 (95% CI: 13.7-15.7) months. The mean cost per patient was 27,624 ± 17,263 euros (31% representing pemetrexed and bevacizumab costs). Multivariate analyses retained men, age >70 years, chronic renal failure, chronic respiratory failure, and never receiving pemetrexed as factors of poor prognosis. After adjusting the analysis to age, sex, and co-morbidities, living in rural/semi-rural area was associated with better 2-year survival (HR: 0.83 [95% CI: 0.73-0.94]; P < 0.01); social deprivation index was not significantly associated with survival. With approximately 1,000 new cases per year in France, MPMs represents a significant national health care burden. Co-morbidities, sex, age, and living place appear to be significant factors of prognosis. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  9. Chemoembolization With Doxorubicin-Eluting Beads for Unresectable Hepatocellular Carcinoma: Five-Year Survival Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Malagari, Katerina, E-mail: kmalag@otonet.gr [University of Athens, Second Department of Radiology (Greece); Pomoni, Mary [University of Athens, Imaging and Research Unit (Greece); Moschouris, Hippocrates, E-mail: hipmosch@gmail.com [Tzanion Hospital, Department of Radiology (Greece); Bouma, Evanthia [University of Athens, Imaging and Research Unit (Greece); Koskinas, John [Ippokration Hospital, University of Athens, Department of Internal Medicine and Hepatology (Greece); Stefaniotou, Aspasia [University of Athens, Imaging and Research Unit (Greece); Marinis, Athanasios [Tzanion Hospital, Department of Surgery (Greece); Kelekis, Alexios; Alexopoulou, Efthymia [University of Athens, Second Department of Radiology (Greece); Chatziioannou, Achilles [University of Athens, First Department of Radiology (Greece); Chatzimichael, Katerina [University of Athens, Second Department of Radiology (Greece); Dourakis, Spyridon [Ippokration Hospital, University of Athens, Department of Internal Medicine and Hepatology (Greece); Kelekis, Nikolaos [University of Athens, Second Department of Radiology (Greece); Rizos, Spyros [Tzanion Hospital, Department of Surgery (Greece); Kelekis, Dimitrios [University of Athens, Imaging and Research Unit (Greece)

    2012-10-15

    Purpose: The purpose of this study was to report on the 5-year survival of hepatocellular carcinoma (HCC) patients treated with DC Bead loaded with doxorubicin (DEB-DOX) in a scheduled scheme in up to three treatments and thereafter on demand. Materials and Methods: 173 HCC patients not suitable for curable treatments were prospectively enrolled (mean age 70.4 {+-} 7.4 years). Child-Pugh (Child) class was A/B (102/71 [59/41 %]), Okuda stage was 0/1/2 (91/61/19 [53.2/35.7/11.1 %]), and mean lesion diameter was 7.6 {+-} 2.1 cm. Lesion morphology was one dominant {<=}5 cm (22 %), one dominant >5 cm (41.6 %), multifocal {<=}5 (26 %), and multifocal >5 (10.4 %). Results: Overall survival at 1, 2, 3, 4, and 5 years was 93.6, 83.8, 62, 41.04, and 22.5 %, with higher rates achieved in Child class A compared with Child class B patients (95, 88.2, 61.7, 45, and 29.4 % vs. 91.5, 75, 50.7, 35.2, and 12.8 %). Mean overall survival was 43.8 months (range 1.2-64.8). Cumulative survival was better for Child class A compared with Child class B patients (p = 0.029). For patients with dominant lesions {<=}5 cm 1-, 2-, 3-, 4-, and 5-year survival rates were 100, 95.2, 71.4, 66.6, and 47.6 % for Child class A and 94.1, 88.2, 58.8, 41.2, 29.4, and 23.5 % for Child class B patients. Regarding DEB-DOX treatment, multivariate analysis identified number of lesions (p = 0.033), lesion vascularity (p < 0.0001), initially achieved complete response (p < 0.0001), and objective response (p = 0.046) as significant and independent determinants of 5-year survival. Conclusion: DEB-DOX results, with high rates of 5-year survival for patients, not amenable to curative treatments. Number of lesions, lesion vascularity, and local response were significant independent determinants of 5-year survival.

  10. Chemoembolization With Doxorubicin-Eluting Beads for Unresectable Hepatocellular Carcinoma: Five-Year Survival Analysis

    International Nuclear Information System (INIS)

    Malagari, Katerina; Pomoni, Mary; Moschouris, Hippocrates; Bouma, Evanthia; Koskinas, John; Stefaniotou, Aspasia; Marinis, Athanasios; Kelekis, Alexios; Alexopoulou, Efthymia; Chatziioannou, Achilles; Chatzimichael, Katerina; Dourakis, Spyridon; Kelekis, Nikolaos; Rizos, Spyros; Kelekis, Dimitrios

    2012-01-01

    Purpose: The purpose of this study was to report on the 5-year survival of hepatocellular carcinoma (HCC) patients treated with DC Bead loaded with doxorubicin (DEB-DOX) in a scheduled scheme in up to three treatments and thereafter on demand. Materials and Methods: 173 HCC patients not suitable for curable treatments were prospectively enrolled (mean age 70.4 ± 7.4 years). Child-Pugh (Child) class was A/B (102/71 [59/41 %]), Okuda stage was 0/1/2 (91/61/19 [53.2/35.7/11.1 %]), and mean lesion diameter was 7.6 ± 2.1 cm. Lesion morphology was one dominant ≤5 cm (22 %), one dominant >5 cm (41.6 %), multifocal ≤5 (26 %), and multifocal >5 (10.4 %). Results: Overall survival at 1, 2, 3, 4, and 5 years was 93.6, 83.8, 62, 41.04, and 22.5 %, with higher rates achieved in Child class A compared with Child class B patients (95, 88.2, 61.7, 45, and 29.4 % vs. 91.5, 75, 50.7, 35.2, and 12.8 %). Mean overall survival was 43.8 months (range 1.2–64.8). Cumulative survival was better for Child class A compared with Child class B patients (p = 0.029). For patients with dominant lesions ≤5 cm 1-, 2-, 3-, 4-, and 5-year survival rates were 100, 95.2, 71.4, 66.6, and 47.6 % for Child class A and 94.1, 88.2, 58.8, 41.2, 29.4, and 23.5 % for Child class B patients. Regarding DEB-DOX treatment, multivariate analysis identified number of lesions (p = 0.033), lesion vascularity (p < 0.0001), initially achieved complete response (p < 0.0001), and objective response (p = 0.046) as significant and independent determinants of 5-year survival. Conclusion: DEB-DOX results, with high rates of 5-year survival for patients, not amenable to curative treatments. Number of lesions, lesion vascularity, and local response were significant independent determinants of 5-year survival.

  11. WIPP fire hazards and risk analysis

    International Nuclear Information System (INIS)

    1991-05-01

    The purpose of this analysis was to conduct a fire hazards risk analysis of the Transuranic (TRU) contact-handled waste receipt, emplacement, and disposal activities at the Waste Isolation Pilot Plant (WIPP). The technical bases and safety envelope for these operations are defined in the approved WIPP Final Safety Analysis Report (FSAR). Although the safety documentation for the initial phase of the Test Program, the dry bin scale tests, has not yet been approved by the Department of Energy (DOE), reviews of the draft to date, including those by the Advisory Committee on Nuclear Facility Safety (ACNFS), have concluded that the dry bin scale tests present no significant risks in excess of those estimated in the approved WIPP FSAR. It is the opinion of the authors and reviewers of this analysis, based on sound engineering judgment and knowledge of the WIPP operations, that a Fire Hazards and Risk Analysis specific to the dry bin scale test program is not warranted prior to first waste receipt. This conclusion is further supported by the risk analysis presented in this document which demonstrates the level of risk to WIPP operations posed by fire to be extremely low. 15 refs., 41 figs., 48 tabs

  12. Mechanisms and mediation in survival analysis: towards an integrated analytical framework.

    Science.gov (United States)

    Pratschke, Jonathan; Haase, Trutz; Comber, Harry; Sharp, Linda; de Camargo Cancela, Marianna; Johnson, Howard

    2016-02-29

    A wide-ranging debate has taken place in recent years on mediation analysis and causal modelling, raising profound theoretical, philosophical and methodological questions. The authors build on the results of these discussions to work towards an integrated approach to the analysis of research questions that situate survival outcomes in relation to complex causal pathways with multiple mediators. The background to this contribution is the increasingly urgent need for policy-relevant research on the nature of inequalities in health and healthcare. The authors begin by summarising debates on causal inference, mediated effects and statistical models, showing that these three strands of research have powerful synergies. They review a range of approaches which seek to extend existing survival models to obtain valid estimates of mediation effects. They then argue for an alternative strategy, which involves integrating survival outcomes within Structural Equation Models via the discrete-time survival model. This approach can provide an integrated framework for studying mediation effects in relation to survival outcomes, an issue of great relevance in applied health research. The authors provide an example of how these techniques can be used to explore whether the social class position of patients has a significant indirect effect on the hazard of death from colon cancer. The results suggest that the indirect effects of social class on survival are substantial and negative (-0.23 overall). In addition to the substantial direct effect of this variable (-0.60), its indirect effects account for more than one quarter of the total effect. The two main pathways for this indirect effect, via emergency admission (-0.12), on the one hand, and hospital caseload, on the other, (-0.10) are of similar size. The discrete-time survival model provides an attractive way of integrating time-to-event data within the field of Structural Equation Modelling. The authors demonstrate the efficacy

  13. Mechanisms and mediation in survival analysis: towards an integrated analytical framework

    Directory of Open Access Journals (Sweden)

    Jonathan Pratschke

    2016-02-01

    Full Text Available Abstract Background A wide-ranging debate has taken place in recent years on mediation analysis and causal modelling, raising profound theoretical, philosophical and methodological questions. The authors build on the results of these discussions to work towards an integrated approach to the analysis of research questions that situate survival outcomes in relation to complex causal pathways with multiple mediators. The background to this contribution is the increasingly urgent need for policy-relevant research on the nature of inequalities in health and healthcare. Methods The authors begin by summarising debates on causal inference, mediated effects and statistical models, showing that these three strands of research have powerful synergies. They review a range of approaches which seek to extend existing survival models to obtain valid estimates of mediation effects. They then argue for an alternative strategy, which involves integrating survival outcomes within Structural Equation Models via the discrete-time survival model. This approach can provide an integrated framework for studying mediation effects in relation to survival outcomes, an issue of great relevance in applied health research. The authors provide an example of how these techniques can be used to explore whether the social class position of patients has a significant indirect effect on the hazard of death from colon cancer. Results The results suggest that the indirect effects of social class on survival are substantial and negative (-0.23 overall. In addition to the substantial direct effect of this variable (-0.60, its indirect effects account for more than one quarter of the total effect. The two main pathways for this indirect effect, via emergency admission (-0.12, on the one hand, and hospital caseload, on the other, (-0.10 are of similar size. Conclusions The discrete-time survival model provides an attractive way of integrating time-to-event data within the field of

  14. Tracheostomy and invasive mechanical ventilation in amyotrophic lateral sclerosis: decision-making factors and survival analysis.

    Science.gov (United States)

    Kimura, Fumiharu

    2016-04-28

    Invasive and/or non-invasive mechanical ventilation are most important options of respiratory management in amyotrophic lateral sclerosis. We evaluated the frequency, clinical characteristics, decision-making factors about ventilation and survival analysis of 190 people with amyotrophic lateral sclerosis patients from 1990 until 2013. Thirty-one percentage of patients underwent tracheostomy invasive ventilation with the rate increasing more than the past 20 years. The ratio of tracheostomy invasive ventilation in patients >65 years old was significantly increased after 2000 (25%) as compared to before (10%). After 2010, the standard use of non-invasive ventilation showed a tendency to reduce the frequency of tracheostomy invasive ventilation. Mechanical ventilation prolonged median survival (75 months in tracheostomy invasive ventilation, 43 months in non-invasive ventilation vs natural course, 32 months). The life-extending effects by tracheostomy invasive ventilation were longer in younger patients ≤65 years old at the time of ventilation support than in older patients. Presence of partners and care at home were associated with better survival. Following factors related to the decision to perform tracheostomy invasive ventilation: patients ≤65 years old: greater use of non-invasive ventilation: presence of a spouse: faster tracheostomy: higher progression rate; and preserved motor functions. No patients who underwent tracheostomy invasive ventilation died from a decision to withdraw mechanical ventilation. The present study provides factors related to decision-making process and survival after tracheostomy and help clinicians and family members to expand the knowledge about ventilation.

  15. Survival analysis of colorectal cancer patients with tumor recurrence using global score test methodology

    Energy Technology Data Exchange (ETDEWEB)

    Zain, Zakiyah, E-mail: zac@uum.edu.my; Ahmad, Yuhaniz, E-mail: yuhaniz@uum.edu.my [School of Quantitative Sciences, Universiti Utara Malaysia, UUM Sintok 06010, Kedah (Malaysia); Azwan, Zairul, E-mail: zairulazwan@gmail.com, E-mail: farhanaraduan@gmail.com, E-mail: drisagap@yahoo.com; Raduan, Farhana, E-mail: zairulazwan@gmail.com, E-mail: farhanaraduan@gmail.com, E-mail: drisagap@yahoo.com; Sagap, Ismail, E-mail: zairulazwan@gmail.com, E-mail: farhanaraduan@gmail.com, E-mail: drisagap@yahoo.com [Surgery Department, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, 56000 Bandar Tun Razak, Kuala Lumpur (Malaysia); Aziz, Nazrina, E-mail: nazrina@uum.edu.my

    2014-12-04

    Colorectal cancer is the third and the second most common cancer worldwide in men and women respectively, and the second in Malaysia for both genders. Surgery, chemotherapy and radiotherapy are among the options available for treatment of patients with colorectal cancer. In clinical trials, the main purpose is often to compare efficacy between experimental and control treatments. Treatment comparisons often involve several responses or endpoints, and this situation complicates the analysis. In the case of colorectal cancer, sets of responses concerned with survival times include: times from tumor removal until the first, the second and the third tumor recurrences, and time to death. For a patient, the time to recurrence is correlated to the overall survival. In this study, global score test methodology is used in combining the univariate score statistics for comparing treatments with respect to each survival endpoint into a single statistic. The data of tumor recurrence and overall survival of colorectal cancer patients are taken from a Malaysian hospital. The results are found to be similar to those computed using the established Wei, Lin and Weissfeld method. Key factors such as ethnic, gender, age and stage at diagnose are also reported.

  16. The survival analysis of beta thalassemia major patients in South East of Iran

    International Nuclear Information System (INIS)

    Roudbari, M.; Soltani-Rad, M.; Roudbari, S.

    2008-01-01

    The objective was to determine the survival of beta-thalassemia major patients with transfusion, and its related factors in Southeast of Iran. This cross-sectional study was performed in Zahedan, Iran in 2007. The sample included patients who were referred from all over the Zahedan Thalassemia Center from 1998 to 2006. The data were collected using the patient's records, which were recorded by the staff during transfusion. The data included demographic and medical information blood group, blood RH, the kind of transfused blood [KTB], annual number of transfusions [ANOT], accompanied disease [AD], Hemoglobin [Hb] and ferritin level. For data analysis, the Kaplan-Meyer method, and Long Rank test together with Cox Regression were used. Forty-six of 578 patients died and 99% survived for the first year. The ages survival proportions were 5 (97.9%), 10 (97%), 15 (92.1%), and 20 (81.2%) years. The survival time showed significant relationships with the ANOT p=0.0053, KTB p=0.003, Hb=0.002 and ferritin level p=0.0087, and AD p=0.00. Using regular transfusion, paying attention to screening of transfused blood, increasing the families knowledge on the disease to prevent the bearing of thalassemia fetus, are recommended; finally, the detection and treating of the AD, are of great importance to extend the lifetime of the patients. (author)

  17. Risk-adjusted survival for adults following in-hospital cardiac arrest by day of week and time of day: observational cohort study

    Science.gov (United States)

    Robinson, Emily J; Power, Geraldine S; Nolan, Jerry; Soar, Jasmeet; Spearpoint, Ken; Gwinnutt, Carl; Rowan, Kathryn M

    2016-01-01

    Background Internationally, hospital survival is lower for patients admitted at weekends and at night. Data from the UK National Cardiac Arrest Audit (NCAA) indicate that crude hospital survival was worse after in-hospital cardiac arrest (IHCA) at night versus day, and at weekends versus weekdays, despite similar frequency of events. Objective To describe IHCA demographics during three day/time periods—weekday daytime (Monday to Friday, 08:00 to 19:59), weekend daytime (Saturday and Sunday, 08:00 to 19:59) and night-time (Monday to Sunday, 20:00 to 07:59)—and to compare the associated rates of return of spontaneous circulation (ROSC) for >20 min (ROSC>20 min) and survival to hospital discharge, adjusted for risk using previously developed NCAA risk models. To consider whether any observed difference could be attributed to differences in the case mix of patients resident in hospital and/or the administered care. Methods We performed a prospectively defined analysis of NCAA data from 27 700 patients aged ≥16 years receiving chest compressions and/or defibrillation and attended by a hospital-based resuscitation team in response to a resuscitation (2222) call in 146 UK acute hospitals. Results Risk-adjusted outcomes (OR (95% CI)) were worse (p20 min 0.88 (0.81 to 0.95); hospital survival 0.72 (0.64 to 0.80)), and night-time (ROSC>20 min 0.72 (0.68 to 0.76); hospital survival 0.58 (0.54 to 0.63)) compared with weekday daytime. The effects were stronger for non-shockable than shockable rhythms, but there was no significant interaction between day/time of arrest and age, or day/time of arrest and arrest location. While many daytime IHCAs involved procedures, restricting the analyses to IHCAs in medical admissions with an arrest location of ward produced results that are broadly in line with the primary analyses. Conclusions IHCAs attended by the hospital-based resuscitation team during nights and weekends have substantially worse outcomes than during

  18. Risk-adjusted survival for adults following in-hospital cardiac arrest by day of week and time of day: observational cohort study.

    Science.gov (United States)

    Robinson, Emily J; Smith, Gary B; Power, Geraldine S; Harrison, David A; Nolan, Jerry; Soar, Jasmeet; Spearpoint, Ken; Gwinnutt, Carl; Rowan, Kathryn M

    2016-11-01

    Internationally, hospital survival is lower for patients admitted at weekends and at night. Data from the UK National Cardiac Arrest Audit (NCAA) indicate that crude hospital survival was worse after in-hospital cardiac arrest (IHCA) at night versus day, and at weekends versus weekdays, despite similar frequency of events. To describe IHCA demographics during three day/time periods-weekday daytime (Monday to Friday, 08:00 to 19:59), weekend daytime (Saturday and Sunday, 08:00 to 19:59) and night-time (Monday to Sunday, 20:00 to 07:59)-and to compare the associated rates of return of spontaneous circulation (ROSC) for >20 min (ROSC>20 min) and survival to hospital discharge, adjusted for risk using previously developed NCAA risk models. To consider whether any observed difference could be attributed to differences in the case mix of patients resident in hospital and/or the administered care. We performed a prospectively defined analysis of NCAA data from 27 700 patients aged ≥16 years receiving chest compressions and/or defibrillation and attended by a hospital-based resuscitation team in response to a resuscitation (2222) call in 146 UK acute hospitals. Risk-adjusted outcomes (OR (95% CI)) were worse (p20 min 0.88 (0.81 to 0.95); hospital survival 0.72 (0.64 to 0.80)), and night-time (ROSC>20 min 0.72 (0.68 to 0.76); hospital survival 0.58 (0.54 to 0.63)) compared with weekday daytime. The effects were stronger for non-shockable than shockable rhythms, but there was no significant interaction between day/time of arrest and age, or day/time of arrest and arrest location. While many daytime IHCAs involved procedures, restricting the analyses to IHCAs in medical admissions with an arrest location of ward produced results that are broadly in line with the primary analyses. IHCAs attended by the hospital-based resuscitation team during nights and weekends have substantially worse outcomes than during weekday daytimes. Organisational or care differences at

  19. Post-Operative Infection Is an Independent Risk Factor for Worse Long-Term Survival after Colorectal Cancer Surgery.

    Science.gov (United States)

    Kerin Povšič, Milena; Ihan, Alojz; Beovič, Bojana

    2016-12-01

    Colorectal cancer surgery is associated with a high incidence of post-operative infections, the outcome of which may be improved if diagnosed and treated early enough. We compared white blood cell (WBC) count, C-reactive protein (CRP), and procalcitonin (PCT) as predictors of post-operative infections and analyzed their impact on long-term survival. This retrospective study included 186 patients undergoing colorectal surgery. Post-operative values of WBC, CRP, and PCT were analyzed by the receiver operating characteristic (ROC) analysis. We followed infections 30 d after the surgery. A five-year survival was analyzed by Kaplan-Meier method and prognostic factors by Cox regression model. Fifty-five patients (29.5%) developed post-operative infection, the most frequent of which was surgical site infection (SSI). C-reactive protein on post-operative day three and PCT on post-operative day two demonstrated the highest diagnostic accuracy for infection (area under the curve [AUC] 0.739 and 0.735). C-reactive protein on post-operative day three was an independent predictor of infection. Five-year survival was higher in the non-infected group (70.8%), compared with the infected group (52.1%). The worst survival (40.9%) was identified in patients with organ/space SSI. Post-operative infection and tumor stage III-IV were independent predictors of a worse five-year survival. C-reactive protein on post-operative day three and PCT on post-operative day two may be early predictors of infection after colorectal cancer surgery. Post-operative infections in particular organ/space SSI have a negative impact on long-term survival.

  20. Standardised risk analysis as a communication tool

    International Nuclear Information System (INIS)

    Pluess, Ch.; Montanarini, M.; Bernauer, M.

    1998-01-01

    Full text of publication follows: several European countries require a risk analysis for the production, storage or transport a dangerous goods. This requirement imposes considerable administrative effort for some sectors of the industry. In order to minimize the effort of such studies, a generic risk analysis for an industrial sector proved to help. Standardised procedures can consequently be derived for efficient performance of the risk investigations. This procedure was successfully established in Switzerland for natural gas transmission lines and fossil fuel storage plants. The development process of the generic risk analysis involved an intense discussion between industry and authorities about methodology of assessment and the criteria of acceptance. This process finally led to scientific consistent modelling tools for risk analysis and to an improved communication from the industry to the authorities and the public. As a recent example, the Holland-Italy natural gas transmission pipeline is demonstrated, where this method was successfully employed. Although this pipeline traverses densely populated areas in Switzerland, using this established communication method, the risk problems could be solved without delaying the planning process. (authors)

  1. Organochlorine exposures influence on breast cancer risk and survival according to estrogen receptor status: a Danish cohort-nested case-control study

    International Nuclear Information System (INIS)

    Høyer, Annette P; Jørgensen, Torben; Rank, Fritz; Grandjean, Philippe

    2001-01-01

    The relationship between breast cancer and organochlorine exposure is controversial and complex. As estrogen receptor positive and negative breast cancer may represent different entities of the disease, this study was undertaken to evaluate organochlorines influence on breast cancer risk and survival according to receptor status. The background material stems from the Copenhagen City Heart Study (Denmark 1976-78). The breast cancer risk was investigated in a cohort nested case-control design including 161 cases and twice as many breast cancer free controls. The cases served as a cohort in the survival analysis. Serum organochlorine concentrations were determined by gaschromotography. The observed increased breast cancer risk associated with exposure to dieldrin derived from women who developed an estrogen receptor negative (ERN) tumor (Odds ratio [OR] I vs. IV quartile, 7.6, 95% confidence interval [95% CI] 1.4-46.1, p-value for linear trend 0.01). Tumors in women with the highest dieldrin serum level were larger and more often spread at the time of diagnosis than ERP tumors. The risk of dying was for the remaining evaluated compounds higher among patients with ERP breast cancer when compared to those with ERN. In the highest quartile of polychlorinated biphenyls (ΣPCB) it was more than 2-fold increased (Relative risk [RR] I vs. IV quartile, 2.5, 95% CI 1.1-5.7), but no dose-response relation was apparent. The results do not suggest that exposure to potential estrogenic organochlorines leads to development of an ERP breast cancer. A possible adverse effect on prognosis of hormone-responsive breast cancers needs to be clarified

  2. Brachytherapy Boost Utilization and Survival in Unfavorable-risk Prostate Cancer.

    Science.gov (United States)

    Johnson, Skyler B; Lester-Coll, Nataniel H; Kelly, Jacqueline R; Kann, Benjamin H; Yu, James B; Nath, Sameer K

    2017-11-01

    There are limited comparative survival data for prostate cancer (PCa) patients managed with a low-dose rate brachytherapy (LDR-B) boost and dose-escalated external-beam radiotherapy (DE-EBRT) alone. To compare overall survival (OS) for men with unfavorable PCa between LDR-B and DE-EBRT groups. Using the National Cancer Data Base, we identified men with unfavorable PCa treated between 2004 and 2012 with androgen suppression (AS) and either EBRT followed by LDR-B or DE-EBRT (75.6-86.4Gy). Treatment selection was evaluated using logistic regression and annual percentage proportions. OS was analyzed using the Kaplan-Meier method, log-rank test, Cox proportional hazards, and propensity score matching. We identified 25038 men between 2004 and 2012, during which LDR-B boost utilization decreased from 29% to 14%. LDR-B was associated with better OS on univariate (7-yr OS: 82% vs 73%; pLDR-B boost (HR 0.74, 95% CI 0.66-0.89). The OS benefit of LDR-B boost persisted when limited to men aged LDR-B boost utilization declined and was associated with better OS compared to DE-EBRT alone. LDR-B boost is probably the ideal treatment option for men with unfavorable PCa, pending long-term results of randomized trials. We compared radiotherapy utilization and survival for prostate cancer (PCa) patients using a national database. We found that low-dose rate brachytherapy (LDR-B) boost, a method being used less frequently, was associated with better overall survival when compared to dose-escalated external-beam radiotherapy alone for men with unfavorable PCa. Randomized trials are needed to confirm that LDR-B boost is the ideal treatment. Copyright © 2017 European Association of Urology. Published by Elsevier B.V. All rights reserved.

  3. The informal economy in Belgium's hotel and catering sector: survival strategy and crime risk

    OpenAIRE

    Klima, Noel

    2012-01-01

    This paper reports on explanatory qualitative research into the illegal economy within the hotel and catering industry in Belgium. Low profitability, exacerbated by pricing pressures customers and suppliers, predispose hotel and catering entrepreneurs to attempting a variety of non-legal modes of economic survival, including involvement in a ‘black market’ (‘off the books’ trading) between providers, suppliers and some customers. There are similar arrangements for the highly fluid workforce, ...

  4. Long-term event-free and overall survival after risk-adapted melphalan and SCT for systemic light chain amyloidosis.

    Science.gov (United States)

    Landau, H; Smith, M; Landry, C; Chou, J F; Devlin, S M; Hassoun, H; Bello, C; Giralt, S; Comenzo, R L

    2017-01-01

    Stem cell transplantation (SCT), an effective therapy for amyloid light chain (AL) amyloidosis patients, is associated with low treatment-related mortality (TRM) with appropriate patient selection and risk-adapted dosing of melphalan (RA-SCT). Consolidation after SCT increases hematologic complete response (CR) rates and may improve overall survival (OS) for patients with SCT with or without consolidation. Melphalan was administered at 100 (14%), 140 (52%) and 200 (34%) mg/m 2 . The TRM rate at 100 days was 5%. RA-SCT resulted in CR in 24% (3 months) and 48% (12 months) of patients. The CR rate was particularly high (62%) in patients offered bortezomib consolidation. With a median follow-up among survivors of 7.7 years, median event-free survival (EFS) with RA-SCT was 4.04 years (95% confidence interval (CI): 3.41-5.01 years); median OS was 10.4 years (95% CI: 7.3-not achieved). Patients with CR at 12 months after SCT had significantly longer EFS (P=0.01) and OS (P=0.04). In a multivariate analysis, melphalan dose had no impact on EFS (P=0.26) or OS (P=0.11). For selected patients, RA-SCT was safe and was associated with extended long-term survival. With the availability of novel agents for consolidation, RA-SCT remains a very effective and important backbone treatment for AL amyloidosis.

  5. Long‐Term Post‐CABG Survival: Performance of Clinical Risk Models Versus Actuarial Predictions

    Science.gov (United States)

    Carr, Brendan M.; Romeiser, Jamie; Ruan, Joyce; Gupta, Sandeep; Seifert, Frank C.; Zhu, Wei

    2015-01-01

    Abstract Background/aim Clinical risk models are commonly used to predict short‐term coronary artery bypass grafting (CABG) mortality but are less commonly used to predict long‐term mortality. The added value of long‐term mortality clinical risk models over traditional actuarial models has not been evaluated. To address this, the predictive performance of a long‐term clinical risk model was compared with that of an actuarial model to identify the clinical variable(s) most responsible for any differences observed. Methods Long‐term mortality for 1028 CABG patients was estimated using the Hannan New York State clinical risk model and an actuarial model (based on age, gender, and race/ethnicity). Vital status was assessed using the Social Security Death Index. Observed/expected (O/E) ratios were calculated, and the models' predictive performances were compared using a nested c‐index approach. Linear regression analyses identified the subgroup of risk factors driving the differences observed. Results Mortality rates were 3%, 9%, and 17% at one‐, three‐, and five years, respectively (median follow‐up: five years). The clinical risk model provided more accurate predictions. Greater divergence between model estimates occurred with increasing long‐term mortality risk, with baseline renal dysfunction identified as a particularly important driver of these differences. Conclusions Long‐term mortality clinical risk models provide enhanced predictive power compared to actuarial models. Using the Hannan risk model, a patient's long‐term mortality risk can be accurately assessed and subgroups of higher‐risk patients can be identified for enhanced follow‐up care. More research appears warranted to refine long‐term CABG clinical risk models. doi: 10.1111/jocs.12665 (J Card Surg 2016;31:23–30) PMID:26543019

  6. Surrogacy of progression-free survival (PFS) for overall survival (OS) in esophageal cancer trials with preoperative therapy: Literature-based meta-analysis.

    Science.gov (United States)

    Kataoka, K; Nakamura, K; Mizusawa, J; Kato, K; Eba, J; Katayama, H; Shibata, T; Fukuda, H

    2017-10-01

    There have been no reports evaluating progression-free survival (PFS) as a surrogate endpoint in resectable esophageal cancer. This study was conducted to evaluate the trial level correlations between PFS and overall survival (OS) in resectable esophageal cancer with preoperative therapy and to explore the potential benefit of PFS as a surrogate endpoint for OS. A systematic literature search of randomized trials with preoperative chemotherapy or preoperative chemoradiotherapy for esophageal cancer reported from January 1990 to September 2014 was conducted using PubMed and the Cochrane Library. Weighted linear regression using sample size of each trial as a weight was used to estimate coefficient of determination (R 2 ) within PFS and OS. The primary analysis included trials in which the HR for both PFS and OS was reported. The sensitivity analysis included trials in which either HR or median survival time of PFS and OS was reported. In the sensitivity analysis, HR was estimated from the median survival time of PFS and OS, assuming exponential distribution. Of 614 articles, 10 trials were selected for the primary analysis and 15 for the sensitivity analysis. The primary analysis did not show a correlation between treatment effects on PFS and OS (R 2 0.283, 95% CI [0.00-0.90]). The sensitivity analysis did not show an association between PFS and OS (R 2 0.084, 95% CI [0.00-0.70]). Although the number of randomized controlled trials evaluating preoperative therapy for esophageal cancer is limited at the moment, PFS is not suitable for primary endpoint as a surrogate endpoint for OS. Copyright © 2017 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

  7. Analysis of prognostic factors for survival in patients with primary spinal chordoma using the SEER Registry from 1973 to 2014.

    Science.gov (United States)

    Pan, Yue; Lu, Lingyun; Chen, Junquan; Zhong, Yong; Dai, Zhehao

    2018-04-06

    Spinal chordomas are rare primary osseous tumors that arise from the remnants of the notochord. They are commonly considered slow-growing, locally invasive neoplasms with little tendency to metastasize, but the high recurrent rate of spinal chordomas may seriously affect the survival rate and quality of life of patients. The aim of the study is to describe the epidemiological data and determine the prognostic factors for decreased survival in patients with primary spinal chordoma. The Surveillance, Epidemiology, and End Results (SEER) Registry database, a US population-based cancer registry database, was used to identify all patients diagnosed with primary spinal chordoma from 1973 to 2014. We utilized Kaplan-Meier method and Cox proportional hazards regression analysis to evaluate the association between patients overall survival and relevant characteristics, including age, gender, race, disease stage, treatment methods, primary tumor site, marital status, and urban county background. In the data set between 1973 and 2014, a total of 808 patients were identified with primary spinal chordoma. The overall rate of distant metastatic cases in our cohort was only 7.7%. Spinal chordoma was more common occurred in men (62.6%) than women (37.3%). Majority of neoplasms were found in the White (87.9%), while the incidence of the Black is relatively infrequent (3.3%). Three hundred fifty-seven spinal chordomas (44.2%) were located in the vertebral column, while 451 patients' tumor (55.8%) was located in the sacrum or pelvis. Age ≥ 60 years (HR = 2.72; 95%CI, 1.71 to 2.89), distant metastasis (HR = 2.16; 95%CI, 1.54 to 3.02), and non-surgical therapy (HR = 2.14; 95%CI, 1.72 to 2.69) were independent risk factors for survival reduction in analysis. Survival did not significantly differ as a factor of tumor site (vertebrae vs sacrum/pelvis) for primary spinal chordoma (HR = 0.93, P = 0.16). Race (P = 0.52), gender (P = 0.11), marital status (P = 0.94), and

  8. Risk analysis of industrial plants operation

    International Nuclear Information System (INIS)

    Hubert, Philippe

    1989-12-01

    This study examines the possibilities of systematic technology risk analysis in view of territorial management (city, urban community, region), including chronic and accidental risks. The objective was to relate this evaluation with those done for permanent water and air pollution. Risk management for pollution are done for a long time. A number of studies were done in urban communities and regions both for air and water pollution. The second objective is related to management of industrial risks: nuclear, petrochemical, transport of hazardous material, pipelines, etc. At the beginning, three possibilities of effects are taken into account: human health, economic aspect and water, and possibilities of evaluation are identified. Elements of risk identification are presented for quantification of results [fr

  9. Risk analysis of alternative energy sources

    International Nuclear Information System (INIS)

    Kazmer, D.R.

    1982-01-01

    The author explores two points raised by Miller Spangler in a January 1981 issue: public perception of risks involving nuclear power plants relative to those of conventional plants and criteria for evaluating the way risk analyses are made. On the first point, he concludes that translating public attitudes into the experts' language of probability and risk could provide better information and understanding of both the attitudes and the risks. Viewing risk analysis methodologies as filters which help to test historical change, he suggests that the lack of information favors a lay jury approach for energy decisions. Spangler responds that Congress is an example of lay decision making, but that a lay jury, given public disinterest and polarization, would probably not improve social justice on the nuclear issue. 5 references, 4 figures

  10. Analysis on Lung Cancer Survival from 2001 to 2007 in Qidong, China

    Directory of Open Access Journals (Sweden)

    Jian ZHU

    2011-01-01

    Full Text Available Background and objective Lung cancer is one of the most important malignancies in China. Survival rates of lung cancer on the population-based cancer registry for the years 2001-2007 in Qidong were analysed in order to provide the basis for the prognosis assessment and the control of this cancer. Methods Total 4,451 registered lung cancer cases was followed up to December 31st, 2009. Death certificates only (DCO cases were excluded, leaving 4,382 cases for survival analysis. Cumulative observed survival rate (OS and relative survival rate (RS were calculated using Hakulinen’s method performed by the SURV 3.01 software developed at the Finnish Cancer Registry. Results The 1-, 3-, and 5-year OS rates were 23.73%, 11.89%, 10.01%, and the RS rates were 24.86%, 13.69%, 12.73%, respectively. The 1-, 3-, and 5-year RS of males vs females were 23.70% vs 27.89%, 12.58% vs 16.53%, and 11.73% vs 15.21%, respectively, with statisitically significant differences (χ2=13.77, P=0.032. RS of age groups of 15-34, 35-44, 45-54, 55-64, 65-74 and 75+ were 35.46%, 17.66%, 11.97%, 13.49%, 10.61%, 15.14%, respectively. Remarkable improvement could be seen for the 5-year RS in this setting if compared with that for the years 1972-2000. Conclusion The lung cancer survival outcomes in Qidong have been improved gradually for the past decades. Further measures on the prevention, diagnosis and treatment of lung cancer should be taken.

  11. The costs of treating acute heart failure: an economic analysis of the SURVIVE trial.

    Science.gov (United States)

    de Lissovoy, Gregory; Fraeman, Kathy; Salon, Jeff; Chay Woodward, Tatia; Sterz, Raimund

    2008-01-01

    To estimate the incremental cost per life year gained with levosimendan relative to dobutamine in treatment of acute heart failure based on the Survival of Patients with Acute Heart Failure in Need of Intravenous Inotropic Support (SURVIVE) trial. SURVIVE enrolled 1,327 patients (levosimendan 664, dobutamine 663) from nine nations with 180-day survival from date of randomisation as the primary endpoint. Hospital resource utilisation was determined via clinical case reports. Unit costs were derived from hospital payment schedules for France, Germany and the UK, and represent a third-party payer perspective. Cost-effectiveness analysis was performed for a subset of the SURVIVE patient population selected in accordance with current levosimendan labeling. Mortality in the levosimendan group was 26 versus 28% for dobutamine (hazard ratio 0.91, 95% confidence interval 0.74-1.13, p=0.40). Initial hospitalisation length of stay was identical (levosimendan 14.4, dobutamine 14.5, p=0.98). Slightly lower rates of readmission were observed for levosimendan relative to dobutamine at 31 (p=0.13) and 180 days (p=0.23). Mean costs excluding study drug were equivalent for the index admission (levosimendan euro5,060, dobutamine euro4,952; p=0.91) and complete episode (levosimendan euro5,396, dobutamine euro5,275; p=0.93). At an acquisition cost of euro600 per vial, there is at least 50% likelihood that levosimendan is cost effective relative to dobutamine if willingness to pay is equal to or greater than euro15,000 per life year gained.

  12. Survival analysis with functional covariates for partial follow-up studies.

    Science.gov (United States)

    Fang, Hong-Bin; Wu, Tong Tong; Rapoport, Aaron P; Tan, Ming

    2016-12-01

    Predictive or prognostic analysis plays an increasingly important role in the era of personalized medicine to identify subsets of patients whom the treatment may benefit the most. Although various time-dependent covariate models are available, such models require that covariates be followed in the whole follow-up period. This article studies a new class of functional survival models where the covariates are only monitored in a time interval that is shorter than the whole follow-up period. This paper is motivated by the analysis of a longitudinal study on advanced myeloma patients who received stem cell transplants and T cell infusions after the transplants. The absolute lymphocyte cell counts were collected serially during hospitalization. Those patients are still followed up if they are alive after hospitalization, while their absolute lymphocyte cell counts cannot be measured after that. Another complication is that absolute lymphocyte cell counts are sparsely and irregularly measured. The conventional method using Cox model with time-varying covariates is not applicable because of the different lengths of observation periods. Analysis based on each single observation obviously underutilizes available information and, more seriously, may yield misleading results. This so-called partial follow-up study design represents increasingly common predictive modeling problem where we have serial multiple biomarkers up to a certain time point, which is shorter than the total length of follow-up. We therefore propose a solution to the partial follow-up design. The new method combines functional principal components analysis and survival analysis with selection of those functional covariates. It also has the advantage of handling sparse and irregularly measured longitudinal observations of covariates and measurement errors. Our analysis based on functional principal components reveals that it is the patterns of the trajectories of absolute lymphocyte cell counts, instead of

  13. LANDSAFE: LANDING SITE RISK ANALYSIS SOFTWARE FRAMEWORK

    OpenAIRE

    Schmidt, Ralph; Bostelmann, Jonas; Cornet, Yves; Heipke, Christian; Philippe, Christian; Poncelet, Nadia; de Rosa, Diego; Vandeloise, Yannick

    2012-01-01

    The European Space Agency (ESA) is planning a Lunar Lander mission in the 2018 timeframe that will demonstrate precise soft landing at the polar regions of the Moon. To ensure a safe and successful landing a careful risk analysis has to be carried out. This is comprised of identifying favorable target areas and evaluating the surface conditions in these areas. Features like craters, boulders, steep slopes, rough surfaces and shadow areas have to be identified in order to assess the risk assoc...

  14. Impact Analysis for Risks in Informatics Systems

    OpenAIRE

    Baicu, Floarea; Baches, Maria Alexandra

    2013-01-01

    In this paper are presented methods of impact analysis on informatics system security accidents, qualitative and quantitative methods, starting with risk and informational system security definitions. It is presented the relationship between the risks of exploiting vulnerabilities of security system, security level of these informatics systems, probability of exploiting the weak points subject to financial losses of a company, respectively impact of a security accident on the company. Herewit...

  15. Association Between Treatment at a High-Volume Facility and Improved Survival for Radiation-Treated Men With High-Risk Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yu-Wei [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, Massachusetts (United States); Mahal, Brandon A. [Department of Medicine, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States); Muralidhar, Vinayak [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States); Nezolosky, Michelle [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, Massachusetts (United States); Beard, Clair J. [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States); Den, Robert B. [Department of Radiation Oncology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Feng, Felix Y. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Hoffman, Karen E. [Department of Radiation Oncology, the University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Martin, Neil E.; Orio, Peter F. [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States); Nguyen, Paul L., E-mail: pnguyen@LROC.harvard.edu [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States)

    2016-03-15

    Purpose: Although the association between higher hospital volume and improved outcomes has been well-documented in surgery, there is little data about whether this effect exists for radiation-treated patients. We investigated whether treatment at a radiation facility that treats a high volume of prostate cancer patients is associated with improved survival for men with high-risk prostate cancer. Methods and Materials: We used the National Cancer Database (NCDB) to identity patients diagnosed with prostate cancer from 2004 to 2006. The radiation case volume (RCV) of each hospital was based on its number of radiation-treated prostate cancer patients. We used propensity-score based analysis to compare the overall survival (OS) of high-risk prostate cancer patients in high versus low RCV hospitals. Primary endpoint is overall survival. Covariates adjusted for were tumor characteristics, sociodemographic factors, radiation type, and use of androgen deprivation therapy (ADT). Results: A total of 19,565 radiation-treated high-risk patients were identified. Median follow-up was 81.0 months (range: 1-108 months). When RCV was coded as a continuous variable, each increment of 100 radiation-managed patients was associated with improved OS (adjusted hazard ratio [AHR]: 0.97; 95% confidence interval [CI]: 0.95-0.98; P<.0001) after adjusting for known confounders. For illustrative purposes, when RCV was dichotomized at the 80th percentile (43 patients/year), high RCV was associated with improved OS (7-year overall survival 76% vs 74%, log-rank test P=.0005; AHR: 0.91, 95% CI: 0.86-0.96, P=.0005). This association remained significant when RCV was dichotomized at 75th (37 patients/year), 90th (60 patients/year), and 95th (84 patients/year) percentiles but not the 50th (19 patients/year). Conclusions: Our results suggest that treatment at centers with higher prostate cancer radiation case volume is associated with improved OS for radiation-treated men with high-risk prostate

  16. Association between obesity with disease-free survival and overall survival in triple-negative breast cancer: A meta-analysis.

    Science.gov (United States)

    Mei, Lin; He, Lin; Song, Yuhua; Lv, Yang; Zhang, Lijiu; Hao, Fengxi; Xu, Mengmeng

    2018-05-01

    To investigate the relationship between obesity and disease-free survival (DFS) and overall survival (OS) of triple-negative breast cancer. Citations were searched in PubMed, Cochrane Library, and Web of Science. Random effect model meta-analysis was conducted by using Revman software version 5.0, and publication bias was evaluated by creating Egger regression with STATA software version 12. Nine studies (4412 patients) were included for DFS meta-analysis, 8 studies (4392 patients) include for OS meta-analysis. There were no statistical significances between obesity with DFS (P = .60) and OS (P = .71) in triple-negative breast cancer (TNBC) patients. Obesity has no impact on DFS and OS in patients with TNBC.

  17. Impact of Nitrate Use on Survival in Acute Heart Failure: A Propensity-Matched Analysis.

    Science.gov (United States)

    Ho, Edwin C; Parker, John D; Austin, Peter C; Tu, Jack V; Wang, Xuesong; Lee, Douglas S

    2016-02-12

    There is limited evidence that the use of nitrates in acute decompensated heart failure early after presentation to a hospital can improve clinical outcomes. We aimed to determine whether early nitrate exposure is associated with improved survival in a large retrospective cohort study. We examined 11 078 acute decompensated heart failure patients who presented to emergency departments in Ontario, Canada, between 2004 and 2007, in the Enhanced Feedback For Effective Cardiac Treatment and the Emergency Heart failure Mortality Risk Grade studies. In propensity-matched analyses, we examined the effect of nitrate administration in the acute emergency department setting for its impact on death at 7, 30, and 365 days. In propensity-matched analyses, we found no difference in survival between those who received nitrates in the emergency department and the non-nitrate comparator group. Hazard ratios for mortality were 0.76 (95% CI; 0.51, 1.12) over 7 days, 0.97 (95% CI; 0.77, 1.21) over 30 days, and 0.91 (95% CI; 0.82, 1.02) over 1 year of follow-up. There was no significant difference in survival or hospital length of stay between nitrate and non-nitrate controls in extended follow-up. There was also no significant effect of nitrates in subgroups stratified by presence of chest pain, troponin elevation, chronic nitrate use, and known coronary artery disease. In acute decompensated heart failure, use of nitrates acutely in the emergency department setting was not associated with improvement in short-term or near-term survival. Our study does not support generalized use of nitrates when the primary goal of therapy is to reduce mortality. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  18. Critical care admission following elective surgery was not associated with survival benefit: prospective analysis of data from 27 countries.

    Science.gov (United States)

    Kahan, Brennan C; Koulenti, Desponia; Arvaniti, Kostoula; Beavis, Vanessa; Campbell, Douglas; Chan, Matthew; Moreno, Rui; Pearse, Rupert M

    2017-07-01

    As global initiatives increase patient access to surgical treatments, there is a need to define optimal levels of perioperative care. Our aim was to describe the relationship between the provision and use of critical care resources and postoperative mortality. Planned analysis of data collected during an international 7-day cohort study of adults undergoing elective in-patient surgery. We used risk-adjusted mixed-effects logistic regression models to evaluate the association between admission to critical care immediately after surgery and in-hospital mortality. We evaluated hospital-level associations between mortality and critical care admission immediately after surgery, critical care admission to treat life-threatening complications, and hospital provision of critical care beds. We evaluated the effect of national income using interaction tests. 44,814 patients from 474 hospitals in 27 countries were available for analysis. Death was more frequent amongst patients admitted directly to critical care after surgery (critical care: 103/4317 patients [2%], standard ward: 99/39,566 patients [0.3%]; adjusted OR 3.01 [2.10-5.21]; p analysis including only high-risk patients yielded similar findings. We did not identify any survival benefit from critical care admission following surgery.

  19. Association of GSTO1 and GSTO2 Polymorphism with Risk of End-Stage Renal Disease Development and Patient Survival

    Directory of Open Access Journals (Sweden)

    Cimbaljevic Slavica

    2016-09-01

    Full Text Available Background: Oxidative stress in patients with end-stage renal disease (ESRD is associated with long-term cardiovascular complications. The cytosolic family of glutathione S-transferases (GSTs is involved in the detoxication of various toxic compounds and antioxidant protection. GST omega class members, GSTO1 and GSTO2 possess, unlike other GSTs, dehydroascorbate reductase and deglutathionylation activities. The aim of this study was to clarify the role of genetic polymorphisms of GSTO1 (rs4925 and GSTO2 (rs156697 as risk determinants for ESRD development, as well as in the survival of these patients.

  20. Hypofractionated radiation therapy for invasive thyroid carcinoma in dogs: a retrospective analysis of survival

    International Nuclear Information System (INIS)

    Brearley, M.J.; Hayes, A.M.; Murphy, S.

    1999-01-01

    Thirteen dogs with invasive thyroid carcinoma (WHO classification T2b or T3b) seen between January 1991 and October 1997 were treated by external beam Irradiation. Four once-weekly fractions of 9 gray of 4 MeV X-rays were administered. Four of the dogs died of progression of the primary disease and four from metastatic spread. Of the remaining dogs, three died of unrelated problems, although two were still alive at the time of the censor. Kaplan-Meier analysis of the survival time from first dose to death from either primary or metastatic disease gave a median survival time of 96 weeks (mean 85 weeks, range six to 247 weeks). Radiographic evidence of pulmonary metastatic disease at presentation had no prognostic value whereas crude growth rate was a highly significant factor. The present series Indicates that radiation therapy should be considered an important modality for the control of invasive thyroid carcinoma in the dog

  1. Mathematical analysis of 51Cr-labelled red cell survival curves in congenital haemolytic anaemias

    International Nuclear Information System (INIS)

    Kasfiki, A.G.; Antipas, S.E.; Dimitriou, P.A.; Gritzali, F.A.; Melissinos, K.G.

    1982-01-01

    The parameters of 51 Cr labelled red cell survival curves were calculated in 26 patients with homozygous β-thalassaemia, 8 with sickle-cell anaemia and 3 with s-β-thalassaemia, using a non-linear weighted least squares analysis computer program. In thalassaemic children the calculated parameters denote that the shorting of the mean cell life is due to early senescence alone, while there is some evidence that in thalassaemic adults additional extracellular destruction mechanisms participate as well. Red cell survival curves from patients with sickle-cell anaemia and s-β-thalassaemia resemble each other, while their parameters indicate an initial rapid loss of radioactivity, early senescence and the presence of extracellular red cell destruction factors. (orig.)

  2. The application of cure models in the presence of competing risks: a tool for improved risk communication in population-based cancer patient survival.

    Science.gov (United States)

    Eloranta, Sandra; Lambert, Paul C; Andersson, Therese M-L; Björkholm, Magnus; Dickman, Paul W

    2014-09-01

    Quantifying cancer patient survival from the perspective of cure is clinically relevant. However, most cure models estimate cure assuming no competing causes of death. We use a relative survival framework to demonstrate how flexible parametric cure models can be used in combination with competing-risks theory to incorporate noncancer deaths. Under a model that incorporates statistical cure, we present the probabilities that cancer patients (1) have died from their cancer, (2) have died from other causes, (3) will eventually die from their cancer, or (4) will eventually die from other causes, all as a function of time since diagnosis. We further demonstrate how conditional probabilities can be used to update the prognosis among survivors (eg, at 1 or 5 years after diagnosis) by summarizing the proportion of patients who will not die from their cancer. The proposed method is applied to Swedish population-based data for persons diagnosed with melanoma, colon cancer, or acute myeloid leukemia between 1973 and 2007.

  3. Risk Assessment and Integration Team (RAIT) Portfolio Risk Analysis Strategy

    Science.gov (United States)

    Edwards, Michelle

    2010-01-01

    Impact at management level: Qualitative assessment of risk criticality in conjunction with risk consequence, likelihood, and severity enable development of an "investment policy" towards managing a portfolio of risks. Impact at research level: Quantitative risk assessments enable researchers to develop risk mitigation strategies with meaningful risk reduction results. Quantitative assessment approach provides useful risk mitigation information.

  4. New risk metrics and mathematical tools for risk analysis: Current and future challenges

    International Nuclear Information System (INIS)

    Skandamis, Panagiotis N.; Andritsos, Nikolaos; Psomas, Antonios; Paramythiotis, Spyridon

    2015-01-01

    The current status of the food safety supply world wide, has led Food and Agriculture Organization (FAO) and World Health Organization (WHO) to establishing Risk Analysis as the single framework for building food safety control programs. A series of guidelines and reports that detail out the various steps in Risk Analysis, namely Risk Management, Risk Assessment and Risk Communication is available. The Risk Analysis approach enables integration between operational food management systems, such as Hazard Analysis Critical Control Points, public health and governmental decisions. To do that, a series of new Risk Metrics has been established as follows: i) the Appropriate Level of Protection (ALOP), which indicates the maximum numbers of illnesses in a population per annum, defined by quantitative risk assessments, and used to establish; ii) Food Safety Objective (FSO), which sets the maximum frequency and/or concentration of a hazard in a food at the time of consumption that provides or contributes to the ALOP. Given that ALOP is rather a metric of the public health tolerable burden (it addresses the total ‘failure’ that may be handled at a national level), it is difficult to be interpreted into control measures applied at the manufacturing level. Thus, a series of specific objectives and criteria for performance of individual processes and products have been established, all of them assisting in the achievement of FSO and hence, ALOP. In order to achieve FSO, tools quantifying the effect of processes and intrinsic properties of foods on survival and growth of pathogens are essential. In this context, predictive microbiology and risk assessment have offered an important assistance to Food Safety Management. Predictive modelling is the basis of exposure assessment and the development of stochastic and kinetic models, which are also available in the form of Web-based applications, e.g., COMBASE and Microbial Responses Viewer), or introduced into user

  5. New risk metrics and mathematical tools for risk analysis: Current and future challenges

    Energy Technology Data Exchange (ETDEWEB)

    Skandamis, Panagiotis N., E-mail: pskan@aua.gr; Andritsos, Nikolaos, E-mail: pskan@aua.gr; Psomas, Antonios, E-mail: pskan@aua.gr; Paramythiotis, Spyridon, E-mail: pskan@aua.gr [Laboratory of Food Quality Control and Hygiene, Department of Food Science and Technology, Agricultural University of Athens, Iera Odos 75, 118 55, Athens (Greece)

    2015-01-22

    The current status of the food safety supply world wide, has led Food and Agriculture Organization (FAO) and World Health Organization (WHO) to establishing Risk Analysis as the single framework for building food safety control programs. A series of guidelines and reports that detail out the various steps in Risk Analysis, namely Risk Management, Risk Assessment and Risk Communication is available. The Risk Analysis approach enables integration between operational food management systems, such as Hazard Analysis Critical Control Points, public health and governmental decisions. To do that, a series of new Risk Metrics has been established as follows: i) the Appropriate Level of Protection (ALOP), which indicates the maximum numbers of illnesses in a population per annum, defined by quantitative risk assessments, and used to establish; ii) Food Safety Objective (FSO), which sets the maximum frequency and/or concentration of a hazard in a food at the time of consumption that provides or contributes to the ALOP. Given that ALOP is rather a metric of the public health tolerable burden (it addresses the total ‘failure’ that may be handled at a national level), it is difficult to be interpreted into control measures applied at the manufacturing level. Thus, a series of specific objectives and criteria for performance of individual processes and products have been established, all of them assisting in the achievement of FSO and hence, ALOP. In order to achieve FSO, tools quantifying the effect of processes and intrinsic properties of foods on survival and growth of pathogens are essential. In this context, predictive microbiology and risk assessment have offered an important assistance to Food Safety Management. Predictive modelling is the basis of exposure assessment and the development of stochastic and kinetic models, which are also available in the form of Web-based applications, e.g., COMBASE and Microbial Responses Viewer), or introduced into user

  6. New risk metrics and mathematical tools for risk analysis: Current and future challenges

    Science.gov (United States)

    Skandamis, Panagiotis N.; Andritsos, Nikolaos; Psomas, Antonios; Paramythiotis, Spyridon

    2015-01-01

    The current status of the food safety supply world wide, has led Food and Agriculture Organization (FAO) and World Health Organization (WHO) to establishing Risk Analysis as the single framework for building food safety control programs. A series of guidelines and reports that detail out the various steps in Risk Analysis, namely Risk Management, Risk Assessment and Risk Communication is available. The Risk Analysis approach enables integration between operational food management systems, such as Hazard Analysis Critical Control Points, public health and governmental decisions. To do that, a series of new Risk Metrics has been established as follows: i) the Appropriate Level of Protection (ALOP), which indicates the maximum numbers of illnesses in a population per annum, defined by quantitative risk assessments, and used to establish; ii) Food Safety Objective (FSO), which sets the maximum frequency and/or concentration of a hazard in a food at the time of consumption that provides or contributes to the ALOP. Given that ALOP is rather a metric of the public health tolerable burden (it addresses the total `failure' that may be handled at a national level), it is difficult to be interpreted into control measures applied at the manufacturing level. Thus, a series of specific objectives and criteria for performance of individual processes and products have been established, all of them assisting in the achievement of FSO and hence, ALOP. In order to achieve FSO, tools quantifying the effect of processes and intrinsic properties of foods on survival and growth of pathogens are essential. In this context, predictive microbiology and risk assessment have offered an important assistance to Food Safety Management. Predictive modelling is the basis of exposure assessment and the development of stochastic and kinetic models, which are also available in the form of Web-based applications, e.g., COMBASE and Microbial Responses Viewer), or introduced into user-friendly softwares

  7. Surviving crack: a qualitative study of the strategies and tactics developed by Brazilian users to deal with the risks associated with the drug

    Directory of Open Access Journals (Sweden)

    Nappo Solange A

    2010-11-01

    Full Text Available Abstract Background Due to marginalization, trafficking violence, conflicts with the police and organic and social psychological problems associated with the drug, crack is one of the most devastating drugs currently in use. However, there is evidence that some users manage to stay alive and active while using crack cocaine for many years, despite the numerous adversities and risks involved with this behavior. In this context, the aim of the present study was to identify the strategies and tactics developed by crack users to deal with the risks associated with the culture of use by examining the survival strategies employed by long-term users. Method A qualitative research method was used involving semi-structured, in-depth interviews. Twenty-eight crack users fulfilling a pre-defined enrollment criterion were interviewed. This criterion was defined as the long-term use of crack (i.e., at least four years. The sample was selected using information provided by key informants and distributed across eight different supply chains. The interviews were literally transcribed and analyzed via content analysis techniques using NVivo-8 software. Results There was diversity in the sample with regard to economic and education levels. The average duration of crack use was 11.5 years. Respondents believed that the greatest risks of crack dependence were related to the drug's psychological effects (e.g., cravings and transient paranoid symptoms and those arising from its illegality (e.g., clashes with the police and trafficking. Protection strategies focused on the control of the psychological effects, primarily through the consumption of alcohol and marijuana. To address the illegality of the drug, strategies were developed to deal with dealers and the police; these strategies were considered crucial for survival. Conclusions The strategies developed by the respondents focused on trying to protect themselves. They proved generally effective, though they

  8. New algorithm for risk analysis in radiotherapy

    International Nuclear Information System (INIS)

    Torres, Antonio; Montes de Oca, Joe

    2015-01-01

    Risk analyses applied to radiotherapy treatments have become an undeniable necessity, considering the dangers generated by the combination of using powerful radiation fields on patients and the occurrence of human errors and equipment failures during these treatments. The technique par excellence to execute these analyses has been the risk matrix. This paper presents the development of a new algorithm to execute the task with wide graphic and analytic potentialities, thus transforming it into a very useful option for risk monitoring and the optimization of quality assurance. The system SECURE- MR, which is the basic software of this algorithm, has been successfully used in risk analysis regarding different kinds of radiotherapies. Compared to previous methods, It offers new possibilities of analysis considering risk controlling factors as the robustness of reducers of initiators frequency and its consequences. Their analytic capacities and graphs allow novel developments to classify risk contributing factors, to represent information processes as well as accidental sequences. The paper shows the application of the proposed system to a generic process of radiotherapy treatment using a lineal accelerator. (author)

  9. Effect of Haloperidol on Survival Among Critically Ill Adults With a High Risk of Delirium: The REDUCE Randomized Clinical Trial.

    Science.gov (United States)

    van den Boogaard, Mark; Slooter, Arjen J C; Brüggemann, Roger J M; Schoonhoven, Lisette; Beishuizen, Albertus; Vermeijden, J Wytze; Pretorius, Danie; de Koning, Jan; Simons, Koen S; Dennesen, Paul J W; Van der Voort, Peter H J; Houterman, Saskia; van der Hoeven, J G; Pickkers, Peter; van der Woude, Margaretha C. E.; Besselink, Anna; Hofstra, Lieuwe S; Spronk, Peter E; van den Bergh, Walter; Donker, Dirk W; Fuchs, Malaika; Karakus, Attila; Koeman, M; van Duijnhoven, Mirella; Hannink, Gerjon

    2018-02-20

    Results of studies on use of prophylactic haloperidol in critically ill adults are inconclusive, especially in patients at high risk of delirium. To determine whether prophylactic use of haloperidol improves survival among critically ill adults at high risk of delirium, which was defined as an anticipated intensive care unit (ICU) stay of at least 2 days. Randomized, double-blind, placebo-controlled investigator-driven study involving 1789 critically ill adults treated at 21 ICUs, at which nonpharmacological interventions for delirium prevention are routinely used in the Netherlands. Patients without delirium whose expected ICU stay was at least a day were included. Recruitment was from July 2013 to December 2016 and follow-up was conducted at 90 days with the final follow-up on March 1, 2017. Patients received prophylactic treatment 3 times daily intravenously either 1 mg (n = 350) or 2 mg (n = 732) of haloperidol or placebo (n = 707), consisting of 0.9% sodium chloride. The primary outcome was the number of days that patients survived in 28 days. There were 15 secondary outcomes, including delirium incidence, 28-day delirium-free and coma-free days, duration of mechanical ventilation, and ICU and hospital length of stay. All 1789 randomized patients (mean, age 66.6 years [SD, 12.6]; 1099 men [61.4%]) completed the study. The 1-mg haloperidol group was prematurely stopped because of futility. There was no difference in the median days patients survived in 28 days, 28 days in the 2-mg haloperidol group vs 28 days in the placebo group, for a difference of 0 days (95% CI, 0-0; P = .93) and a hazard ratio of 1.003 (95% CI, 0.78-1.30, P=.82). All of the 15 secondary outcomes were not statistically different. These included delirium incidence (mean difference, 1.5%, 95% CI, -3.6% to 6.7%), delirium-free and coma-free days (mean difference, 0 days, 95% CI, 0-0 days), and duration of mechanical ventilation, ICU, and hospital length of stay (mean difference

  10. Clinical Outcomes Among Children With Standard-Risk Medulloblastoma Treated With Proton and Photon Radiation Therapy: A Comparison of Disease Control and Overall Survival.

    Science.gov (United States)

    Eaton, Bree R; Esiashvili, Natia; Kim, Sungjin; Weyman, Elizabeth A; Thornton, Lauren T; Mazewski, Claire; MacDonald, Tobey; Ebb, David; MacDonald, Shannon M; Tarbell, Nancy J; Yock, Torunn I

    2016-01-01

    The purpose of this study was to compare long-term disease control and overall survival between children treated with proton and photon radiation therapy (RT) for standard-risk medulloblastoma. This multi-institution cohort study includes 88 children treated with chemotherapy and proton (n=45) or photon (n=43) RT between 2000 and 2009. Overall survival (OS), recurrence-free survival (RFS), and patterns of failure were compared between the 2 cohorts. Median (range) age was 6 years old at diagnosis (3-21 years) for proton patients versus 8 years (3-19 years) for photon patients (P=.011). Cohorts were similar with respect to sex, histology, extent of surgical resection, craniospinal irradiation (CSI) RT dose, total RT dose, whether the RT boost was delivered to the posterior fossa (PF) or tumor bed (TB), time from surgery to RT start, or total duration of RT. RT consisted of a median (range) CSI dose of 23.4 Gy (18-27 Gy) and a boost of 30.6 Gy (27-37.8 Gy). Median follow-up time is 6.2 years (95% confidence interval [CI]: 5.1-6.6 years) for proton patients versus 7.0 years (95% CI: 5.8-8.9 years) for photon patients. There was no significant difference in RFS or OS between patients treated with proton versus photon RT; 6-year RFS was 78.8% versus 76.5% (P=.948) and 6-year OS was 82.0% versus 87.6%, respectively (P=.285). On multivariate analysis, there was a trend for longer RFS with females (P=.058) and higher CSI dose (P=.096) and for longer OS with females (P=.093). Patterns of failure were similar between the 2 cohorts (P=.908). Disease control with proton and photon radiation therapy appears equivalent for standard risk medulloblastoma. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Meta-regression analysis of commensal and pathogenic Escherichia coli survival in soil and water.

    Science.gov (United States)

    Franz, Eelco; Schijven, Jack; de Roda Husman, Ana Maria; Blaak, Hetty

    2014-06-17

    The extent to which pathogenic and commensal E. coli (respectively PEC and CEC) can survive, and which factors predominantly determine the rate of decline, are crucial issues from a public health point of view. The goal of this study was to provide a quantitative summary of the variability in E. coli survival in soil and water over a broad range of individual studies and to identify the most important sources of variability. To that end, a meta-regression analysis on available literature data was conducted. The considerable variation in reported decline rates indicated that the persistence of E. coli is not easily predictable. The meta-analysis demonstrated that for soil and water, the type of experiment (laboratory or field), the matrix subtype (type of water and soil), and temperature were the main factors included in the regression analysis. A higher average decline rate in soil of PEC compared with CEC was observed. The regression models explained at best 57% of the variation in decline rate in soil and 41% of the variation in decline rate in water. This indicates that additional factors, not included in the current meta-regression analysis, are of importance but rarely reported. More complete reporting of experimental conditions may allow future inference on the global effects of these variables on the decline rate of E. coli.

  12. Young patients with colorectal cancer have poor survival in the first twenty months after operation and predictable survival in the medium and long-term: Analysis of survival and prognostic markers

    Directory of Open Access Journals (Sweden)

    Wickramarachchi RE

    2010-09-01

    Full Text Available Abstract Objectives This study compares clinico-pathological features in young (50 years with colorectal cancer, survival in the young and the influence of pre-operative clinical and histological factors on survival. Materials and methods A twelve year prospective database of colorectal cancer was analysed. Fifty-three young patients were compared with forty seven consecutive older patients over fifty years old. An analysis of survival was undertaken in young patients using Kaplan Meier graphs, non parametric methods, Cox's Proportional Hazard Ratios and Weibull Hazard models. Results Young patients comprised 13.4 percent of 397 with colorectal cancer. Duration of symptoms and presentation in the young was similar to older patients (median, range; young patients; 6 months, 2 weeks to 2 years, older patients; 4 months, 4 weeks to 3 years, p > 0.05. In both groups, the majority presented without bowel obstruction (young - 81%, older - 94%. Cancer proximal to the splenic flexure was present more in young than in older patients. Synchronous cancers were found exclusively in the young. Mucinous tumours were seen in 16% of young and 4% of older patients (p Conclusion If patients, who are less than 40 years old with colorectal cancer, survive twenty months after operation, the prognosis improves and their survival becomes predictable.

  13. The impact of metformin use on survival in kidney cancer patients with diabetes: a meta-analysis.

    Science.gov (United States)

    Li, Yang; Hu, Liyi; Xia, Qinghong; Yuan, Yongqiang; Mi, Yonghua

    2017-06-01

    The effects of metformin on the prognosis of kidney cancer patients with diabetes are in controversial. The present study is conducted to classify the association of metformin use with the survival of patients with kidney cancer. Electronic databases, namely PubMed and Web of Science, were used to search the eligible studies up to December, 2016. Pooled hazard ratio (HR) and its corresponding 95% confidence interval (95% CI) were calculated. It was considered as statistically significant when P value was kidney cancer patients. The combined HR suggested that the use of metformin could improve the overall survival (OS) (HR 0.643, 95% CI 0.520-0.795, P cancer-specific survival (CSS) (HR 0.618, 95% CI 0.446-0.858, P = 0.004) in kidney cancer patients. In subgroup analysis, positive associations were found between metformin use and OS/CSS of localized renal cell carcinoma patients (OS: HR 0.634, 95% CI 0.440-0.913, P = 0.014; CSS: HR 0.476, 95% CI 0.295-0.768, P = 0.002). Moreover, we also found that the use of metformin could reduce the risk of death in kidney cancer patients (HR 0.711, 95% CI 0.562-0.899, P = 0.004). Our findings suggest that the use of metformin is in favor of the prognosis of patients with kidney cancers. Further investigations are needed to evaluate the prognostic value of metformin on kidney cancer patients.

  14. Natural histroy of trisomy 18 and trisomy 13: I. Growth, physical assessment, medical histories, survival, and recurrence risk

    Energy Technology Data Exchange (ETDEWEB)

    Baty, B.J.; Blackburn, B.L.; Carey, J.C. [Univ. of Utah School of Medicine, Salt Lake City, UT (United States)

    1994-01-15

    The natural history of trisomy 18 and trisomy 13 was investigated using data derived from parent questionnaires and medical records from 98 families with an index case of trisomy 18 and 32 families with an index case of trisomy 13. Data are presented on pregnancy, delivery, survival, medical complications, immunizations, growth, cause of death, cytogenetics, and recurrence risk. Half of the trisomy 18 babies were delivered by C-section. Fetal distress was a factor in half, and the only reason in a third of C-section deliveries. One minute Apgar scores were significantly lower in C-section and breech deliveries. There were more small-for-gestational-age babies than in the general population, but most of the low-birth-weight newborns were small for gestational age, unlike the general population. Survival in this group of children was better than in other studies due to ascertainment bias. There were more girls than boys at all ages for both conditions, and the sex ratio decreased with time. Growth curves for length, weight, head circumference, and weight vs height are provided. Long-term survival did not appear to be due to mosaicism. There were no adverse reactions attributable to immunizations. At age 1 year there was an average of approximately 2 operations per living child. The authors report the second case of successful major cardiac surgery in a trisomy 18 child. Almost 70% of deaths were attributed to cardiopulmonary arrest. The sibling recurrence risk for trisomy 18 or trisomy 13 was 0.55%. 86 refs., 5 figs., 5 tabs.

  15. The watchdog role of risk analysis

    International Nuclear Information System (INIS)

    Reijen, G. van; Vinck, W.

    1983-01-01

    The reason why the risks of large-scale technology attract more attention lies in the fact that accidents would have more disastrous results and in the fact that it is probably more attractive to study the risks of some large projects than to do the same for a greater number of smaller projects. Within this presentation there will be some opening remarks on the Role of the Commission of the European Community with regard to accident prevention. The development of the concept of quantitative risks is dealt with. This development leads to a combinded of deterministic and probabilistic methods. The presentation concludes with some critical remarks on quantitative risk analysis and its use. (orig./HP) [de

  16. Integrative analysis of survival-associated gene sets in breast cancer.

    Science.gov (United States)

    Varn, Frederick S; Ung, Matthew H; Lou, Shao Ke; Cheng, Chao

    2015-03-12

    Patient gene expression information has recently become a clinical feature used to evaluate breast cancer prognosis. The emergence of prognostic gene sets that take advantage of these data has led to a rich library of information that can be used to characterize the molecular nature of a patient's cancer. Identifying robust gene sets that are consistently predictive of a patient's clinical outcome has become one of the main challenges in the field. We inputted our previously established BASE algorithm with patient gene expression data and gene sets from MSigDB to develop the gene set activity score (GSAS), a metric that quantitatively assesses a gene set's activity level in a given patient. We utilized this metric, along with patient time-to-event data, to perform survival analyses to identify the gene sets that were significantly correlated with patient survival. We then performed cross-dataset analyses to identify robust prognostic gene sets and to classify patients by metastasis status. Additionally, we created a gene set network based on component gene overlap to explore the relationship between gene sets derived from MSigDB. We developed a novel gene set based on this network's topology and applied the GSAS metric to characterize its role in patient survival. Using the GSAS metric, we identified 120 gene sets that were significantly associated with patient survival in all datasets tested. The gene overlap network analysis yielded a novel gene set enriched in genes shared by the robustly predictive gene sets. This gene set was highly correlated to patient survival when used alone. Most interestingly, removal of the genes in this gene set from the gene pool on MSigDB resulted in a large reduction in the number of predictive gene sets, suggesting a prominent role for these genes in breast cancer progression. The GSAS metric provided a useful medium by which we systematically investigated how gene sets from MSigDB relate to breast cancer patient survival. We used

  17. Post-listing survival for highly sensitised patients on the UK kidney transplant waiting list:A matched cohort analysis

    OpenAIRE

    Manook, Miriam Helen; Koeser, Leonardo Alberto; Ahmed, Zubir; Robb, Matthew; Johnson, Rachel; Shaw, Olivia Jane; Kessaris, Nicos; Dorling, Anthony; Mamode, Nizam

    2017-01-01

    Background: More than 40% of patients awaiting a kidney transplant in the UK are sensitised with human leucocyte antigen (HLA) antibodies. Median time to transplantation for such patients is double that of unsensitised patients at about 74 months. Removing antibody to perform an HLA-incompatible (HLAi) living donor transplantation is perceived to be high risk, although patient survival data are limited. We compared survival of patients opting for an HLAi kidney transplant with that of similar...

  18. Implementing the Bayesian paradigm in risk analysis

    International Nuclear Information System (INIS)

    Aven, T.; Kvaloey, J.T.

    2002-01-01

    The Bayesian paradigm comprises a unified and consistent framework for analyzing and expressing risk. Yet, we see rather few examples of applications where the full Bayesian setting has been adopted with specifications of priors of unknown parameters. In this paper, we discuss some of the practical challenges of implementing Bayesian thinking and methods in risk analysis, emphasizing the introduction of probability models and parameters and associated uncertainty assessments. We conclude that there is a need for a pragmatic view in order to 'successfully' apply the Bayesian approach, such that we can do the assignments of some of the probabilities without adopting the somewhat sophisticated procedure of specifying prior distributions of parameters. A simple risk analysis example is presented to illustrate ideas

  19. Talent in Female Gymnastics: a Survival Analysis Based upon Performance Characteristics.

    Science.gov (United States)

    Pion, J; Lenoir, M; Vandorpe, B; Segers, V

    2015-11-01

    This study investigated the link between the anthropometric, physical and motor characteristics assessed during talent identification and dropout in young female gymnasts. 3 cohorts of female gymnasts (n=243; 6-9 years) completed a test battery for talent identification. Performance-levels were monitored over 5 years of competition. Kaplan-Meier and Cox Proportional Hazards analyses were conducted to determine the survival rate and the characteristics that influence dropout respectively. Kaplan-Meier analysis indicated that only 18% of the female gymnasts that passed the baseline talent identification test survived at the highest competition level 5 years later. The Cox Proportional Hazards Model indicated that gymnasts with a score in the best quartile for a specific characteristic significantly increased chances of survival by 45-129%. These characteristics being: basic motor skills (129%), shoulder strength (96%), leg strength (53%) and 3 gross motor coordination items (45-73%). These results suggest that tests batteries commonly used for talent identification in young female gymnasts may also provide valuable insights into future dropout. Therefore, multidimensional test batteries deserve a prominent place in the selection process. The individual test results should encourage trainers to invest in an early development of basic physical and motor characteristics to prevent attrition. © Georg Thieme Verlag KG Stuttgart · New York.

  20. Game Theoretic Risk Analysis of Security Threats

    CERN Document Server

    Bier, Vicki M

    2008-01-01

    Introduces reliability and risk analysis in the face of threats by intelligent agents. This book covers applications to networks, including problems in both telecommunications and transportation. It provides a set of tools for applying game theory TO reliability problems in the presence of intentional, intelligent threats

  1. Economic impact assessment in pest risk analysis

    NARCIS (Netherlands)

    Soliman, T.A.A.; Mourits, M.C.M.; Oude Lansink, A.G.J.M.; Werf, van der W.

    2010-01-01

    According to international treaties, phytosanitary measures against introduction and spread of invasive plant pests must be justified by a science-based pest risk analysis (PRA). Part of the PRA consists of an assessment of potential economic consequences. This paper evaluates the main available

  2. Survival, causes of death, and prognostic factors in systemic sclerosis: analysis of 947 Brazilian patients.

    Science.gov (United States)

    Sampaio-Barros, Percival D; Bortoluzzo, Adriana B; Marangoni, Roberta G; Rocha, Luiza F; Del Rio, Ana Paula T; Samara, Adil M; Yoshinari, Natalino H; Marques-Neto, João Francisco

    2012-10-01

    To analyze survival, prognostic factors, and causes of death in a large cohort of patients with systemic sclerosis (SSc). From 1991 to 2010, 947 patients with SSc were treated at 2 referral university centers in Brazil. Causes of death were considered SSc-related and non-SSc-related. Multiple logistic regression analysis was used to identify prognostic factors. Survival at 5 and 10 years was estimated using the Kaplan-Meier method. One hundred sixty-eight patients died during the followup. Among the 110 deaths considered related to SSc, there was predominance of lung (48.1%) and heart (24.5%) involvement. Most of the 58 deaths not related to SSc were caused by infection, cardiovascular or cerebrovascular disease, and cancer. Male sex, modified Rodnan skin score (mRSS) > 20, osteoarticular involvement, lung involvement, and renal crisis were the main prognostic factors associated to death. Overall survival rate was 90% for 5 years and 84% for 10 years. Patients presented worse prognosis if they had diffuse SSc (85% vs 92% at 5 yrs, respectively, and 77% vs 87% at 10 yrs, compared to limited SSc), male sex (77% vs 90% at 5 yrs and 64% vs 86% at 10 yrs, compared to female sex), and mRSS > 20 (83% vs 90% at 5 yrs and 66% vs 86% at 10 yrs, compared to mRSS < 20). Survival was worse in male patients with diffuse SSc, and lung and heart involvement represented the main causes of death in this South American series of patients with SSc.

  3. Survival analysis using primary care electronic health record data: A systematic review of the literature.

    Science.gov (United States)

    Hodgkins, Adam Jose; Bonney, Andrew; Mullan, Judy; Mayne, Darren John; Barnett, Stephen

    2018-01-01

    An emerging body of research involves observational studies in which survival analysis is applied to data obtained from primary care electronic health records (EHRs). This systematic review of these studies examined the utility of using this approach. An electronic literature search of the Scopus, PubMed, Web of Science, CINAHL, and Cochrane databases was conducted. Search terms and exclusion criteria were chosen to select studies where survival analysis was applied to the data extracted wholly from EHRs used in primary care medical practice. A total of 46 studies that met the inclusion criteria for the systematic review were examined. All were published within the past decade (2005-2014) with a majority ( n = 26, 57%) being published between 2012 and 2014. Even though citation rates varied from nil to 628, over half ( n = 27, 59%) of the studies were cited 10 times or more. The median number of subjects was 18,042 with five studies including over 1,000,000 patients. Of the included studies, 35 (76%) were published in specialty journals and 11 (24%) in general medical journals. The many conditions studied largely corresponded well with conditions important to general practice. Survival analysis applied to primary care electronic medical data is a research approach that has been frequently used in recent times. The utility of this approach was demonstrated by the ability to produce research with large numbers of subjects, across a wide range of conditions and with the potential of a high impact. Importantly, primary care data were thus available to inform primary care practice.

  4. Interactions between SNPs affecting inflammatory response genes are associated with multiple myeloma disease risk and survival

    DEFF Research Database (Denmark)

    Nielsen, Kaspar René; Rodrigo-Domingo, Maria; Steffensen, Rudi

    2017-01-01

    The origin of multiple myeloma depends on interactions with stromal cells in the course of normal B-cell differentiation and evolution of immunity. The concept of the present study is that genes involved in MM pathogenesis, such as immune response genes, can be identified by screening for single......3L1 gene promoters. The occurrence of single polymorphisms, haplotypes and SNP-SNP interactions were statistically analyzed for association with disease risk and outcome following high-dose therapy. Identified genes that carried SNPs or haplotypes that were identified as risk or prognostic factors......= .005). The 'risk genes' were analyzed for expression in normal B-cell subsets (N = 6) from seven healthy donors and we found TNFA and IL-6 expressed both in naïve and in memory B cells when compared to preBI, II, immature and plasma cells. The 'prognosis genes' CHI3L1, IL-6 and IL-10 were differential...

  5. Demographic and Socio-economic Determinants of Birth Interval Dynamics in Manipur: A Survival Analysis

    Directory of Open Access Journals (Sweden)

    Sanajaoba Singh N,

    2011-01-01

    Full Text Available The birth interval is a major determinant of levels of fertility in high fertility populations. A house-to-house survey of 1225 women in Manipur, a tiny state in North Eastern India was carried out to investigate birth interval patterns and its determinants. Using survival analysis, among the nine explanatory variables of interest, only three factors – infant mortality, Lactation and use of contraceptive devices have highly significant effect (P<0.01 on the duration of birth interval and only three factors – age at marriage of wife, parity and sex of child are found to be significant (P<0.05 on the duration variable.

  6. Survival analysis to explore the characteristics of employee assistance program (EAP) referrals that remain employed.

    Science.gov (United States)

    Macdonald, S; Albert, W; Maynard, M; French, P

    1989-02-01

    This study examined characteristics of referrals to employee assistance programs (EAP) associated with subsequent termination of employment. As well, relationships between characteristics of the referrals and program characteristics were explored. Longitudinal data were collected at several time periods for 163 referrals to EAPs from five organizations. Survival analysis was conducted to determine which variables were associated with termination of employment. Females, cohabitating couples, and employees who worked for the organization for 5 or more years were most likely to remain employed. One interesting finding was that people with alcohol problems were significantly more likely to be formal referrals.

  7. Survival benefit of radiotherapy to patients with small cell esophagus carcinoma: an analysis of Surveillance Epidemiology and End Results (SEER) data.

    Science.gov (United States)

    Song, Yaqi; Wang, Wanwei; Tao, Guangzhou; Zhu, Weiguo; Zhou, Xilei; Pan, Peng

    2016-03-29

    Small cell esophageal carcinoma (SCEC) is a rare malignant tumor. So far, few studies are found to research the effect of radiotherapy (RT) to it. This study is designed to explore the prognostic factors, and analyze survival benefit of RT to patients with SCEC. Patients with SCEC were more likely to be in female, older, higher disease stage than those with non-small cell esophageal carcinoma. RT was used in more than 50% SCEC patients. RT tended be reduced as the disease stage raise in SCEC. Univariate and multivariate analysis showed that age, year, disease stage, and RT were the prognostic factors of survival (P 0.05) and nearly 30% risks of death in distant stage (P > 0.05). SCEC patients between 1973 and 2012 were searched from the Surveillance Epidemiology and End Results (SEER) data. Clinical factors including age, year, sex, race, stage, surgery, and RT were summarized. Univariate and multivariate analysis were performed to explore the independent prognostic factors of SCEC. Cox regression survival analysis was performed to evaluate the effect of RT to SCEC based on different stages. Stage, age, year, and RT are independent prognostic factors of SCEC. Survival benefit of RT exists in any disease stage, but is only statistically significant in localized stage of SCEC.

  8. Estimation of failure criteria in multivariate sensory shelf life testing using survival analysis.

    Science.gov (United States)

    Giménez, Ana; Gagliardi, Andrés; Ares, Gastón

    2017-09-01

    For most food products, shelf life is determined by changes in their sensory characteristics. A predetermined increase or decrease in the intensity of a sensory characteristic has frequently been used to signal that a product has reached the end of its shelf life. Considering all attributes change simultaneously, the concept of multivariate shelf life allows a single measurement of deterioration that takes into account all these sensory changes at a certain storage time. The aim of the present work was to apply survival analysis to estimate failure criteria in multivariate sensory shelf life testing using two case studies, hamburger buns and orange juice, by modelling the relationship between consumers' rejection of the product and the deterioration index estimated using PCA. In both studies, a panel of 13 trained assessors evaluated the samples using descriptive analysis whereas a panel of 100 consumers answered a "yes" or "no" question regarding intention to buy or consume the product. PC1 explained the great majority of the variance, indicating all sensory characteristics evolved similarly with storage time. Thus, PC1 could be regarded as index of sensory deterioration and a single failure criterion could be estimated through survival analysis for 25 and 50% consumers' rejection. The proposed approach based on multivariate shelf life testing may increase the accuracy of shelf life estimations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Methodology to predict long-term cancer survival from short-term data using Tobacco Cancer Risk and Absolute Cancer Cure models

    International Nuclear Information System (INIS)

    Mould, R F; Lederman, M; Tai, P; Wong, J K M

    2002-01-01

    Three parametric statistical models have been fully validated for cancer of the larynx for the prediction of long-term 15, 20 and 25 year cancer-specific survival fractions when short-term follow-up data was available for just 1-2 years after the end of treatment of the last patient. In all groups of cases the treatment period was only 5 years. Three disease stage groups were studied, T1N0, T2N0 and T3N0. The models are the Standard Lognormal (SLN) first proposed by Boag (1949 J. R. Stat. Soc. Series B 11 15-53) but only ever fully validated for cancer of the cervix, Mould and Boag (1975 Br. J. Cancer 32 529-50), and two new models which have been termed Tobacco Cancer Risk (TCR) and Absolute Cancer Cure (ACC). In each, the frequency distribution of survival times of defined groups of cancer deaths is lognormally distributed: larynx only (SLN), larynx and lung (TCR) and all cancers (ACC). All models each have three unknown parameters but it was possible to estimate a value for the lognormal parameter S a priori. By reduction to two unknown parameters the model stability has been improved. The material used to validate the methodology consisted of case histories of 965 patients, all treated during the period 1944-1968 by Dr Manuel Lederman of the Royal Marsden Hospital, London, with follow-up to 1988. This provided a follow-up range of 20- 44 years and enabled predicted long-term survival fractions to be compared with the actual survival fractions, calculated by the Kaplan and Meier (1958 J. Am. Stat. Assoc. 53 457-82) method. The TCR and ACC models are better than the SLN model and for a maximum short-term follow-up of 6 years, the 20 and 25 year survival fractions could be predicted. Therefore the numbers of follow-up years saved are respectively 14 years and 19 years. Clinical trial results using the TCR and ACC models can thus be analysed much earlier than currently possible. Absolute cure from cancer was also studied, using not only the prediction models which

  10. Supplemental Hazard Analysis and Risk Assessment - Hydrotreater

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, Peter P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wagner, Katie A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-04-01

    A supplemental hazard analysis was conducted and quantitative risk assessment performed in response to an independent review comment received by the Pacific Northwest National Laboratory (PNNL) from the U.S. Department of Energy Pacific Northwest Field Office (PNSO) against the Hydrotreater/Distillation Column Hazard Analysis Report issued in April 2013. The supplemental analysis used the hazardous conditions documented by the previous April 2013 report as a basis. The conditions were screened and grouped for the purpose of identifying whether additional prudent, practical hazard controls could be identified, using a quantitative risk evaluation to assess the adequacy of the controls and establish a lower level of concern for the likelihood of potential serious accidents. Calculations were performed to support conclusions where necessary.

  11. Survival of cognitively impaired older hospitalized patients at risk of malnutrition

    NARCIS (Netherlands)

    Neelemaat, F.; Bijland, L.R.; Thijs, A.; Seidell, J.C.; van Bokhorst-de van der Schueren, M.A.E.

    2012-01-01

    Introduction: In our society offering extra nutritional support is a standard for malnourished patients at admission to hospital. Whether cognitively impaired, older, hospitalized patients at risk of malnutrition would also benefit from this regimen is unknown. This study assesses their 3-months and

  12. Racial and ethnic disparities in the impact of obesity on breast cancer risk and survival: a global perspective.

    Science.gov (United States)

    Bandera, Elisa V; Maskarinec, Gertraud; Romieu, Isabelle; John, Esther M

    2015-11-01

    Obesity is a global concern, affecting both developed and developing countries. Although there are large variations in obesity and breast cancer rates worldwide and across racial/ethnic groups, most studies evaluating the impact of obesity on breast cancer risk and survival have been conducted in non-Hispanic white women in the United States or Europe. Given the known racial/ethnic differences in tumor hormone receptor subtype distribution, obesity prevalence, and risk factor profiles, we reviewed published data for women of African, Hispanic, and Asian ancestry in the United States and their countries of origin. Although the data are limited, current evidence suggests a stronger adverse effect of obesity on breast cancer risk and survival in women of Asian ancestry. For African Americans and Hispanics, the strength of the associations appears to be more comparable to that of non-Hispanic whites, particularly when accounting for subtype and menopausal status. Central obesity seems to have a stronger impact in African-American women than general adiposity as measured by body mass index. International data from countries undergoing economic transition offer a unique opportunity to evaluate the impact of rapid weight gain on breast cancer. Such studies should take into account genetic ancestry, which may help elucidate differences in associations between ethnically admixed populations. Overall, additional large studies that use a variety of adiposity measures are needed, because the current evidence is based on few studies, most with limited statistical power. Future investigations of obesity biomarkers will be useful to understand possible racial/ethnic biological differences underlying the complex association between obesity and breast cancer development and progression. © 2015 American Society for Nutrition.

  13. Effects of Racial Prejudice on the Health of Communities: A Multilevel Survival Analysis.

    Science.gov (United States)

    Lee, Yeonjin; Muennig, Peter; Kawachi, Ichiro; Hatzenbuehler, Mark L

    2015-11-01

    We examined whether and how racial prejudice at both the individual and community levels contributes to mortality risk among majority as well as minority group members. We used data on racial attitudes from the General Social Survey (1993-2002) prospectively linked to mortality data from the National Death Index through 2008. Whites and Blacks living in communities with higher levels of racial prejudice were at an elevated risk of mortality, independent of individual and community sociodemographic characteristics and individually held racist beliefs (odds ratio = 1.24; 95% confidence interval = 1.04, 1.49). Living in a highly prejudiced community had similar harmful effects among both Blacks and Whites. Furthermore, the interaction observed between individual- and community-level racial prejudice indicated that respondents with higher levels of racial prejudice had lower survival rates if they lived in communities with low degrees of racial prejudice. Community-level social capital explained the relationship between community racial prejudice and mortality. Community-level racial prejudice may disrupt social capital, and reduced social capital is associated with increased mortality risk among both Whites and Blacks. Our results contribute to an emerging body of literature documenting the negative consequences of prejudice for population health.

  14. Effects of Racial Prejudice on the Health of Communities: A Multilevel Survival Analysis

    Science.gov (United States)

    Muennig, Peter; Kawachi, Ichiro; Hatzenbuehler, Mark L.

    2015-01-01

    Objectives. We examined whether and how racial prejudice at both the individual and community levels contributes to mortality risk among majority as well as minority group members. Methods. We used data on racial attitudes from the General Social Survey (1993–2002) prospectively linked to mortality data from the National Death Index through 2008. Results. Whites and Blacks living in communities with higher levels of racial prejudice were at an elevated risk of mortality, independent of individual and community sociodemographic characteristics and individually held racist beliefs (odds ratio = 1.24; 95% confidence interval = 1.04, 1.49). Living in a highly prejudiced community had similar harmful effects among both Blacks and Whites. Furthermore, the interaction observed between individual- and community-level racial prejudice indicated that respondents with higher levels of racial prejudice had lower survival rates if they lived in communities with low degrees of racial prejudice. Community-level social capital explained the relationship between community racial prejudice and mortality. Conclusions. Community-level racial prejudice may disrupt social capital, and reduced social capital is associated with increased mortality risk among both Whites and Blacks. Our results contribute to an emerging body of literature documenting the negative consequences of prejudice for population health. PMID:26378850

  15. Risk and safety analysis of nuclear systems

    CERN Document Server

    Lee, John C

    2011-01-01

    The book has been developed in conjunction with NERS 462, a course offered every year to seniors and graduate students in the University of Michigan NERS program. The first half of the book covers the principles of risk analysis, the techniques used to develop and update a reliability data base, the reliability of multi-component systems, Markov methods used to analyze the unavailability of systems with repairs, fault trees and event trees used in probabilistic risk assessments (PRAs), and failure modes of systems. All of this material is general enough that it could be used in non-nuclear a

  16. Terminological Ontologies for Risk and Vulnerability Analysis

    DEFF Research Database (Denmark)

    Madsen, Bodil Nistrup; Erdman Thomsen, Hanne

    2014-01-01

    Risk and vulnerability analyses are an important preliminary stage in civil contingency planning. The Danish Emergency Management Agency has developed a generic model and a set of tools that may be used in the preparedness planning, i.e. for identifying and describing society’s critical functions......, for formulating threat scenarios and for assessing consequences. Terminological ontologies, which are systems of domain specific concepts comprising concept relations and characteristics, are useful, both when describing the central concepts of risk and vulnerability analysis (meta concepts), and for further...

  17. Effect of MDM2 SNP309 and p53 codon 72 polymorphisms on lung cancer risk and survival among non-smoking Chinese women in Singapore

    Directory of Open Access Journals (Sweden)

    Sabapathy Kanaga

    2010-03-01

    Full Text Available Abstract Background Single nucleotide polymorphism (SNP 309 resulting in a T or G allele in the promoter of MDM2, the negative regulator of p53, has been suggested to affect cancer predisposition and age of onset, primarily in females. However, findings have been inconsistent in various cancers, and ethnicity appears to be a critical factor influencing the effects of the SNP on cancer risk. An increasing trend has been observed in the prevalence of lung cancers in non-smokers, especially females, though the underlying genetic basis is unclear. Methods We therefore examined the role of the SNPs in the p53 pathway (p53 codon 72 and MDM2 SNP309 on lung cancer risk and prognosis of a life-time non-smoking female Chinese population, in a hospital-based case-control study of 123 cases and 159 age-matched controls, by PCR analysis. Results Our findings reveal that the risk of lung cancer among individuals with the MDM2 SNP309 TT genotype was 2.1 (95% CI 1.01-4.36 relative to the GG genotype, contrary to initial expectations that the GG genotype with elevated MDM2 levels will increase cancer risk. Those who had this genotype in combination with the p53 Pro allele had a risk of 2.5 (95% CI 1.2-5.0. There was however no effect of either polymorphism on age at diagnosis of lung cancer or on overall survival. Conclusions The results thus demonstrate that the MDM2 SNP309 TT rather than the GG genotype is associated with increased risk of lung cancer in this population, suggesting that other mechanisms independent of increased MDM2 levels can influence cancer susceptibility.

  18. Risk-Adjusted Analysis of Relevant Outcome Drivers for Patients after More Than Two Kidney Transplants

    Directory of Open Access Journals (Sweden)

    Lampros Kousoulas

    2015-01-01

    Full Text Available Renal transplantation is the treatment of choice for patients suffering end-stage renal disease, but as the long-term renal allograft survival is limited, most transplant recipients will face graft loss and will be considered for a retransplantation. The goal of this study was to evaluate the patient and graft survival of the 61 renal transplant recipients after second or subsequent renal transplantation, transplanted in our institution between 1990 and 2010, and to identify risk factors related to inferior outcomes. Actuarial patient survival was 98.3%, 94.8%, and 88.2% after one, three, and five years, respectively. Actuarial graft survival was 86.8%, 80%, and 78.1% after one, three, and five years, respectively. Risk-adjusted analysis revealed that only age at the time of last transplantation had a significant influence on patient survival, whereas graft survival was influenced by multiple immunological and surgical factors, such as the number of HLA mismatches, the type of immunosuppression, the number of surgical complications, need of reoperation, primary graft nonfunction, and acute rejection episodes. In conclusion, third and subsequent renal transplantation constitute a valid therapeutic option, but inferior outcomes should be expected among elderly patients, hyperimmunized recipients, and recipients with multiple operations at the site of last renal transplantation.

  19. Risk analysis for earth dam overtopping

    Directory of Open Access Journals (Sweden)

    Mo Chongxun

    2008-06-01

    Full Text Available In this paper, a model of overtopping risk under the joint effects of floods and wind waves, which is based on risk analysis theory and takes into account the uncertainties of floods, wind waves, reservoir capacity and discharge capacity of the spillway, is proposed and applied to the Chengbihe Reservoir in Baise City in Guangxi Zhuang Autonomous Region. The simulated results indicate that the flood control limiting level can be raised by 0.40 m under the condition that the reservoir overtopping risk is controlled within a mean variance of 5×10−6. As a result, the reservoir storage will increase to 16 million m3 and electrical energy generation and other functions of the reservoir will also increase greatly.

  20. Investment appraisal using quantitative risk analysis.

    Science.gov (United States)

    Johansson, Henrik

    2002-07-01

    Investment appraisal concerned with investments in fire safety systems is discussed. Particular attention is directed at evaluating, in terms of the Bayesian decision theory, the risk reduction that investment in a fire safety system involves. It is shown how the monetary value of the change from a building design without any specific fire protection system to one including such a system can be estimated by use of quantitative risk analysis, the results of which are expressed in terms of a Risk-adjusted net present value. This represents the intrinsic monetary value of investing in the fire safety system. The method suggested is exemplified by a case study performed in an Avesta Sheffield factory.

  1. Survival Analysis of Factors Influencing Cyclic Fatigue of Nickel-Titanium Endodontic Instruments

    Directory of Open Access Journals (Sweden)

    Eva Fišerová

    2015-01-01

    Full Text Available Objective. The aim of this study was to validate a survival analysis assessing the effect of type of rotary system, canal curvature, and instrument size on cyclic resistance. Materials and Methods. Cyclic fatigue testing was carried out in stainless steel artificial canals with radii of curvature of 3 or 5 mm and the angle of curvature of 60 degrees. All the instruments were new and 25 mm in working length, and ISO colour coding indicated the instrument size (yellow for size 20; red for size 25. Wizard Navigator instruments, Mtwo instruments, ProTaper instruments, and Revo-S instruments were passively rotated at 250 rotations per minute, and the time fracture was being recorded. Subsequently, fractographic analysis of broken tips was performed by scanning electron microscope. The data were then analysed by the Kaplan-Meier estimator of the survival function, the Cox proportional hazards model, the Wald test for regression covariates, and the Wald test for significance of regression model. Conclusion. The lifespan registered for the tested instruments was Mtwo > Wizard Navigator > Revo-S > ProTaper; 5 mm radius > 3 mm radius; and yellow > red in ISO colour coding system.

  2. Quantitative Risk Analysis: Method And Process

    Directory of Open Access Journals (Sweden)

    Anass BAYAGA

    2010-03-01

    Full Text Available Recent and past studies (King III report, 2009: 73-75; Stoney 2007;Committee of Sponsoring Organisation-COSO, 2004, Bartell, 2003; Liebenberg and Hoyt, 2003; Reason, 2000; Markowitz 1957 lament that although, the introduction of quantifying risk to enhance degree of objectivity in finance for instance was quite parallel to its development in the manufacturing industry, it is not the same in Higher Education Institution (HEI. In this regard, the objective of the paper was to demonstrate the methods and process of Quantitative Risk Analysis (QRA through likelihood of occurrence of risk (phase I. This paper serves as first of a two-phased study, which sampled hundred (100 risk analysts in a University in the greater Eastern Cape Province of South Africa.The analysis of likelihood of occurrence of risk by logistic regression and percentages were conducted to investigate whether there were a significant difference or not between groups (analyst in respect of QRA.The Hosmer and Lemeshow test was non-significant with a chi-square(X2 =8.181; p = 0.300, which indicated that there was a good model fit, since the data did not significantly deviate from the model. The study concluded that to derive an overall likelihood rating that indicated the probability that a potential risk may be exercised within the construct of an associated threat environment, the following governing factors must be considered: (1 threat source motivation and capability (2 nature of the vulnerability (3 existence and effectiveness of current controls (methods and process.

  3. Is volunteering a public health intervention? A systematic review and meta-analysis of the health and survival of volunteers.

    Science.gov (United States)

    Jenkinson, Caroline E; Dickens, Andy P; Jones, Kerry; Thompson-Coon, Jo; Taylor, Rod S; Rogers, Morwenna; Bambra, Clare L; Lang, Iain; Richards, Suzanne H

    2013-08-23

    Volunteering has been advocated by the United Nations, and American and European governments as a way to engage people in their local communities and improve social capital, with the potential for public health benefits such as improving wellbeing and decreasing health inequalities. Furthermore, the US Corporation for National and Community Service Strategic Plan for 2011-2015 focused on increasing the impact of national service on community needs, supporting volunteers' wellbeing, and prioritising recruitment and engagement of underrepresented populations. The aims of this review were to examine the effect of formal volunteering on volunteers' physical and mental health and survival, and to explore the influence of volunteering type and intensity on health outcomes. Experimental and cohort studies comparing the physical and mental health outcomes and mortality of a volunteering group to a non-volunteering group were identified from twelve electronic databases (Cochrane Library, Medline, Embase, PsychINFO, CINAHL, ERIC, HMIC, SSCI, ASSIA, Social Care Online, Social Policy and Practice) and citation tracking in January 2013. No language, country or date restrictions were applied. Data synthesis was based on vote counting and random effects meta-analysis of mortality risk ratios. Forty papers were selected: five randomised controlled trials (RCTs, seven papers); four non-RCTs; and 17 cohort studies (29 papers). Cohort studies showed volunteering had favourable effects on depression, life satisfaction, wellbeing but not on physical health. These findings were not confirmed by experimental studies. Meta-analysis of five cohort studies found volunteers to be at lower risk of mortality (risk ratio: 0.78; 95% CI: 0.66, 0.90). There was insufficient evidence to demonstrate a consistent influence of volunteering type or intensity on outcomes. Observational evidence suggested that volunteering may benefit mental health and survival although the causal mechanisms remain

  4. Risk analysis as a decision tool

    International Nuclear Information System (INIS)

    Yadigaroglu, G.; Chakraborty, S.

    1985-01-01

    From 1983 - 1985 a lecture series entitled ''Risk-benefit analysis'' was held at the Swiss Federal Institute of Technology (ETH), Zurich, in cooperation with the Central Department for the Safety of Nuclear Installations of the Swiss Federal Agency of Energy Economy. In that setting the value of risk-oriented evaluation models as a decision tool in safety questions was discussed on a broad basis. Experts of international reputation from the Federal Republic of Germany, France, Canada, the United States and Switzerland have contributed to report in this joint volume on the uses of such models. Following an introductory synopsis on risk analysis and risk assessment the book deals with practical examples in the fields of medicine, nuclear power, chemistry, transport and civil engineering. Particular attention is paid to the dialogue between analysts and decision makers taking into account the economic-technical aspects and social values. The recent chemical disaster in the Indian city of Bhopal again signals the necessity of such analyses. All the lectures were recorded individually. (orig./HP) [de

  5. Quantitative risk analysis preoperational of gas pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Manfredi, Carlos; Bispo, Gustavo G.; Esteves, Alvaro [Gie S.A., Buenos Aires (Argentina)

    2009-07-01

    The purpose of this analysis is to predict how it can be affected the individual risk and the public's general security due to the operation of a gas pipeline. In case that the single or social risks are considered intolerable, compared with the international standards, to be recommended measures of mitigation of the risk associated to the operation until levels that can be considered compatible with the best practices in the industry. The quantitative risk analysis calculates the probability of occurrence of an event based on the frequency of occurrence of the same one and it requires a complex mathematical treatment. The present work has as objective to develop a calculation methodology based on the previously mentioned publication. This calculation methodology is centered in defining the frequencies of occurrence of events, according to representative database of each case in study. Besides, it settles down the consequences particularly according to the considerations of each area and the different possibilities of interferences with the gas pipeline in study. For each one of the interferences a typical curve of ignition probabilities is developed in function from the distance to the pipe. (author)

  6. Association of CDX2 Expression With Survival in Early Colorectal Cancer: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Tomasello, Gianluca; Barni, Sandro; Turati, Luca; Ghidini, Michele; Pezzica, Ezio; Passalacqua, Rodolfo; Petrelli, Fausto

    2018-02-15

    CDX2 is a homeobox gene encoding transcriptional factors for intestinal organogenesis and represents a specific marker of colorectal adenocarcinoma (CRC) differentiation. We have evaluated if CDX2 expression is associated with better overall and disease-free survival (OS and DFS) in patients with CRC. PubMed, SCOPUS, EMBASE, The Cochrane Library, and Web of Science (from inception to July 2017) were systematically reviewed for relevant studies on adult patients with CRC where OS and DFS were calculated according to CDX2 expression in uni- or multivariate analysis were included. Hazard ratio (HR) for mortality and/or disease progression was calculated. The search produced 16 studies suitable for inclusion (6291 individual patients). The meta-analysis showed a reduced risk of death for patients with CDX2-positive CRC in 14 studies (HR, 0.5; 95% confidence interval [CI], 0.38-0.66; P < .001 according to random effect model). In 6 studies where only DFS data was available, CDX2 expression led to a 52% lower risk of relapse or death (HR, 0.48; 95% CI, 0.39-0.59; P < .001 according to random effect model). The results did not change as a function of ethnicity, type of study, CDX2 detection modality, or stage. Interestingly, in stages II to III, CDX2 expression was associated with a 70% lower risk of death (HR, 0.3; 95% CI, 0.12-0.77; P = .01). CDX2 expression confirms to be a strong prognostic factor in stage II and III CRC. In this setting, along with other clinical and pathologic factors, the lack of expression of CDX2 may be considered an important variable when deciding for adjuvant chemotherapy. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Acute lymphoblastic leukemia in children and adolescents: prognostic factors and analysis of survival

    Science.gov (United States)

    Lustosa de Sousa, Daniel Willian; de Almeida Ferreira, Francisco Valdeci; Cavalcante Félix, Francisco Helder; de Oliveira Lopes, Marcos Vinicios

    2015-01-01

    Objective To describe the clinical and laboratory features of children and adolescents with acute lymphoblastic leukemia treated at three referral centers in Ceará and evaluate prognostic factors for survival, including age, gender, presenting white blood cell count, immunophenotype, DNA index and early response to treatment. Methods Seventy-six under 19-year-old patients with newly diagnosed acute lymphoblastic leukemia treated with the Grupo Brasileiro de Tratamento de Leucemia da Infância – acute lymphoblastic leukemia-93 and -99 protocols between September 2007 and December 2009 were analyzed. The diagnosis was based on cytological, immunophenotypic and cytogenetic criteria. Associations between variables, prognostic factors and response to treatment were analyzed using the chi-square test and Fisher's exact test. Overall and event-free survival were estimated by Kaplan–Meier analysis and compared using the log-rank test. A Cox proportional hazards model was used to identify independent prognostic factors. Results The average age at diagnosis was 6.3 ± 0.5 years and males were predominant (65%). The most frequently observed clinical features were hepatomegaly, splenomegaly and lymphadenopathy. Central nervous system involvement and mediastinal enlargement occurred in 6.6% and 11.8%, respectively. B-acute lymphoblastic leukemia was more common (89.5%) than T-acute lymphoblastic leukemia. A DNA index >1.16 was found in 19% of patients and was associated with favorable prognosis. On Day 8 of induction therapy, 95% of the patients had lymphoblast counts <1000/μL and white blood cell counts <5.0 × 109/L. The remission induction rate was 95%, the induction mortality rate was 2.6% and overall survival was 72%. Conclusion The prognostic factors identified are compatible with the literature. The 5-year overall and event-free survival rates were lower than those reported for developed countries. As shown by the multivariate analysis, age and baseline white

  8. Acute lymphoblastic leukemia in children and adolescents: prognostic factors and analysis of survival

    Directory of Open Access Journals (Sweden)

    Daniel Willian Lustosa de Sousa

    2015-08-01

    Full Text Available OBJECTIVE: To describe the clinical and laboratory features of children and adolescents with acute lymphoblastic leukemia treated at three referral centers in Ceará and evaluate prognostic factors for survival, including age, gender, presenting white blood cell count, immunophenotype, DNA index and early response to treatment.METHODS: Seventy-six under 19-year-old patients with newly diagnosed acute lymphoblastic leukemia treated with the Grupo Brasileiro de Tratamento de Leucemia da Infância - acute lymphoblastic leukemia-93 and -99 protocols between September 2007 and December 2009 were analyzed. The diagnosis was based on cytological, immunophenotypic and cytogenetic criteria. Associations between variables, prognostic factors and response to treatment were analyzed using the chi-square test and Fisher's exact test. Overall and event-free survival were estimated by Kaplan-Meier analysis and compared using the log-rank test. A Cox proportional hazards model was used to identify independent prognostic factors.RESULTS: The average age at diagnosis was 6.3 ± 0.5 years and males were predominant (65%. The most frequently observed clinical features were hepatomegaly, splenomegaly and lymphadenopathy. Central nervous system involvement and mediastinal enlargement occurred in 6.6% and 11.8%, respectively. B-acute lymphoblastic leukemia was more common (89.5% than T-acute lymphoblastic leukemia. A DNA index >1.16 was found in 19% of patients and was associated with favorable prognosis. On Day 8 of induction therapy, 95% of the patients had lymphoblast counts <1000/µL and white blood cell counts <5.0 Ã- 109/L. The remission induction rate was 95%, the induction mortality rate was 2.6% and overall survival was 72%.CONCLUSION: The prognostic factors identified are compatible with the literature. The 5-year overall and event-free survival rates were lower than those reported for developed countries. As shown by the multivariate analysis, age

  9. Risk analysis in oil spill response planning

    International Nuclear Information System (INIS)

    Chernoplekov, A.N.; Alexandrov, A.A.

    2005-01-01

    Tiered response is a basic approach to emergency plans, including oil spill response (OSR). This paper delineates a huge set of accidental scenarios within a certain tier of response generated by a computer during risk assessment. Parameters such as the amount of oil spilled, duration of discharge and types of losses should be provided in OSR scenarios. Examples of applications include offshore installations, sub sea or onshore pipelines, and localized onshore facilities. The paper demonstrates how to use risk analysis results for delineating all likely spills into groups that need a specific tier response. The best world practices and Russian regulatory approaches were outlined and compared. Corresponding algorithms were developed and their application in pipelines was presented. The algorithm combines expert's skills and spill trajectory modeling with the net environmental benefit analysis principle into the incident specific emergency response planning. 9 refs., 13 tabs., 2 figs

  10. Integrated Reliability and Risk Analysis System (IRRAS)

    International Nuclear Information System (INIS)

    Russell, K.D.; McKay, M.K.; Sattison, M.B.; Skinner, N.L.; Wood, S.T.; Rasmuson, D.M.

    1992-01-01

    The Integrated Reliability and Risk Analysis System (IRRAS) is a state-of-the-art, microcomputer-based probabilistic risk assessment (PRA) model development and analysis tool to address key nuclear plant safety issues. IRRAS is an integrated software tool that gives the user the ability to create and analyze fault trees and accident sequences using a microcomputer. This program provides functions that range from graphical fault tree construction to cut set generation and quantification. Version 1.0 of the IRRAS program was released in February of 1987. Since that time, many user comments and enhancements have been incorporated into the program providing a much more powerful and user-friendly system. This version has been designated IRRAS 4.0 and is the subject of this Reference Manual. Version 4.0 of IRRAS provides the same capabilities as Version 1.0 and adds a relational data base facility for managing the data, improved functionality, and improved algorithm performance

  11. Zero risk fuel fabrication: a systems analysis

    International Nuclear Information System (INIS)

    1979-01-01

    Zero risk is a concept used to ensure that system requirements are developed through a systems approach such that the choice(s) among alternatives represents the balanced viewpoints of performance, achievability and risk. Requirements to ensure characteristics such as stringent accountability, low personnel exposure and etc. are needed to guide the development of component and subsystems for future LMFBR fuel supply systems. To establish a consistent and objective set of requirements, RF and M-TMC has initiated a systems requirements analysis activity. This activity pivots on judgement and experience provided by a Task Force representing industrial companies engaged in fuel fabrication in licensed facilities. The Task Force members are listed in Appendix A. Input developed by this group is presented as a starting point for the systems requirements analysis

  12. Follicular thyroid cancer in children and adolescents. Clinicopathologic features, long-term survival, and risk factors for recurrence

    International Nuclear Information System (INIS)

    Enomoto, Keisuke; Enomoto, Yukie; Uchino, Shinya; Yamashita, Hiroto; Noguchi, Shiro

    2013-01-01

    Children and adolescents represent 1-1.5% of all patients with thyroid cancer (TC). The vast majority of TC in children and adolescents is papillary TC; follicular TC (FTC) is exceedingly rare. In this study, we evaluate the clinical and pathological features of FTC in children and adolescents. We also report the risk factors for post-operative tumor recurrence and the associated outcomes. Twenty children and adolescents (under 21 years old) with FTC have been treated and followed at Noguchi Thyroid Clinic and Hospital Foundation since 1946. All patients underwent surgery (lobectomy, 11; subtotal thyroidectomy, 8; and total thyroidectomy, 1), and 8 patients received postoperative external beam radiation therapy. The incidence of FTC in children and adolescents was 1.9% among all FTC patients treated in our hospital. Histopathology revealed vascular and capsular invasion in 9 and 20 patients, respectively. The tumor recurrence rate in FTC with vascular invasion is significantly higher than in those without it (p=0.038). No other factors were significant. Patients with recurrences were treated with completion thyroidectomy and 131 I radioactive iodine therapy. There were no significant differences in the rates of disease-free survival or cause-specific survival when pediatric/adolescent FTC patients were compared to adults with FTC. FTC is very rare among children and adolescents, but the outcomes are similar to those observed among adults. Vascular invasion is poor prognostic indicator in pediatric/adolescent FTC patients. (author)

  13. Missing data and censoring in the analysis of progression-free survival in oncology clinical trials.

    Science.gov (United States)

    Denne, J S; Stone, A M; Bailey-Iacona, R; Chen, T-T

    2013-01-01

    Progression-free survival (PFS) is increasingly used as a primary endpoint in oncology clinical trials. However, trial conduct is often such that PFS data on some patients may be partially missing either due to incomplete follow-up for progression, or due to data that may be collected but confounded by patients stopping randomized therapy or starting alternative therapy prior to progression. Regulatory guidance on how to handle these patients in the analysis and whether to censor these patients differs between agencies. We present results of a reanalysis of 28 Phase III trials from 12 companies or institutions performed by the Pharmaceutical Research and Manufacturers Association-sponsored PFS Expert Team. We show that analyses not adhering to the intention-to-treat principle tend to give hazard ratio estimates further from unity and describe several factors associated with this shift. We present illustrative simulations to support these findings and provide recommendations for the analysis of PFS.

  14. Suicide, Self-Harm and Survival Strategies in Contemporary Heavy Metal Music: A Cultural and Literary Analysis.

    Science.gov (United States)

    Baker, Charley; Brown, Brian

    2016-03-01

    This paper seeks to think creatively about the body of research which claims there is a link between heavy metal music and adolescent alienation, self-destructive behaviours, self-harm and suicide. Such research has been criticised, often by people who belong to heavy metal subcultures, as systematically neglecting to explore, in a meaningful manner, the psychosocial benefits for individuals who both listen to contemporary heavy metal music and socialize in associated groups. We argue that notions of survival, strength, community, and rebellion are key themes in contemporary heavy metal music. Through literary-lyrical analysis of a selection of heavy metal tracks, this paper aims to redress the balance of risk and benefit. We argue that listening to this type of music, the accompanying social relationships, sense of solidarity and even the type of dancing can ameliorate tumultuous and difficult emotions. Songs which could be read as negative can induce feelings of relief through the sense that someone else has felt a particular way and recovered enough to transform these emotions into a creative outlet. This genre of music may therefore not increase the risk of untoward outcomes in any simple sense but rather represent a valuable resource for young people in difficulty.

  15. Risk Analysis of Accounting Information System Infrastructure

    OpenAIRE

    MIHALACHE, Arsenie-Samoil

    2011-01-01

    National economy and security are fully dependent on information technology and infrastructure. At the core of the information infrastructure society relies on, we have the Internet, a system designed initially as a scientists’ forum for unclassified research. The use of communication networks and systems may lead to hazardous situations that generate undesirable effects such as communication systems breakdown, loss of data or taking the wrong decisions. The paper studies the risk analysis of...

  16. Risk analysis of external radiation therapy

    International Nuclear Information System (INIS)

    Arvidsson, Marcus

    2011-09-01

    External radiation therapy is carried out via a complex treatment process in which many different groups of staff work together. Much of the work is dependent on and in collaboration with advanced technical equipment. The purpose of the research task has been to identify a process for external radiation therapy and to identify, test and analyze a suitable method for performing risk analysis of external radiation therapy

  17. Risk and value analysis of SETI

    Science.gov (United States)

    Billingham, J.

    1990-01-01

    This paper attempts to apply a traditional risk and value analysis to the Search for Extraterrestrial Intelligence--SETI. In view of the difficulties of assessing the probability of success, a comparison is made between SETI and a previous search for extraterrestrial life, the biological component of Project Viking. Our application of simple Utility Theory, given some reasonable assumptions, suggests that SETI is at least as worthwhile as the biological experiment on Viking.

  18. Applied decision analysis and risk evaluation

    International Nuclear Information System (INIS)

    Ferse, W.; Kruber, S.

    1995-01-01

    During 1994 the workgroup 'Applied Decision Analysis and Risk Evaluation; continued the work on the knowledge based decision support system XUMA-GEFA for the evaluation of the hazard potential of contaminated sites. Additionally a new research direction was started which aims at the support of a later stage of the treatment of contaminated sites: The clean-up decision. For the support of decisions arising at this stage, the methods of decision analysis will be used. Computational aids for evaluation and decision support were implemented and a case study at a waste disposal site in Saxony which turns out to be a danger for the surrounding groundwater ressource was initiated. (orig.)

  19. Cost-effectiveness Analysis in R Using a Multi-state Modeling Survival Analysis Framework: A Tutorial.

    Science.gov (United States)

    Williams, Claire; Lewsey, James D; Briggs, Andrew H; Mackay, Daniel F

    2017-05-01

    This tutorial provides a step-by-step guide to performing cost-effectiveness analysis using a multi-state modeling approach. Alongside the tutorial, we provide easy-to-use functions in the statistics package R. We argue that this multi-state modeling approach using a package such as R has advantages over approaches where models are built in a spreadsheet package. In particular, using a syntax-based approach means there is a written record of what was done and the calculations are transparent. Reproducing the analysis is straightforward as the syntax just needs to be run again. The approach can be thought of as an alternative way to build a Markov decision-analytic model, which also has the option to use a state-arrival extended approach. In the state-arrival extended multi-state model, a covariate that represents patients' history is included, allowing the Markov property to be tested. We illustrate the building of multi-state survival models, making predictions from the models and assessing fits. We then proceed to perform a cost-effectiveness analysis, including deterministic and probabilistic sensitivity analyses. Finally, we show how to create 2 common methods of visualizing the results-namely, cost-effectiveness planes and cost-effectiveness acceptability curves. The analysis is implemented entirely within R. It is based on adaptions to functions in the existing R package mstate to accommodate parametric multi-state modeling that facilitates extrapolation of survival curves.