LIVIVO - Search results -

Search results

Result 1 - 10 of total 117

Search options

Article ; Online: Adjuvant chemotherapy and radiation for patients with high-risk stage I endometrial cancer treated with curative intent surgery: impact on recurrence and survival.

Findley, Rachelle / Kooy, Joni / Lester, Beverley / Le, Nhu D / Bowering, Gale / Rugayan, Christie / Kumar, Aalok / Glaze, Sarah / Ko, Jenny

International journal of gynecological cancer : official journal of the International Gynecological Cancer Society

2022 Volume 32, Issue 4, Page(s) 508–516

Abstract: Background: Survival benefits of post-operative systemic and radiation therapy in high-risk stage I endometrial cancer are uncertain.: Objective: To compare recurrence patterns and survival outcomes of post-surgical treatment in patients with high- ... ...

Abstract	Background: Survival benefits of post-operative systemic and radiation therapy in high-risk stage I endometrial cancer are uncertain. Objective: To compare recurrence patterns and survival outcomes of post-surgical treatment in patients with high-risk stage I endometrial cancer and to determine whether adjuvant therapy significantly improves outcomes. Methods: High-risk stage I endometrial cancer was defined as either stage IB grade 3 endometrioid histology or myoinvasive non-endometrioid histology. Consecutive patients diagnosed between January 2000 and December 2010 in eight cancer centers were included. Patients, disease, and treatment characteristics were summarized by descriptive statistics. Overall survival, disease-specific survival, and relapse-free survival were examined using Cox's proportional hazards regression and log-rank test. Survival curves were estimated using the Kaplan-Meier method. Results: Of 2317 patients with stage I endometrial cancer, 414 patients had high-risk disease. Use of chemotherapy did not improve overall survival (relative risk (RR) 0.70, 95% CI 0.46 to 1.14, p=0.13) or disease-specific survival (RR 1.06, 95% CI 0.61 to 1.85, p=0.84). Significant improvement in recurrence-free survival was observed in patients who received chemotherapy (RR 0.61, 95% CI 0.39 to 0.95, p=0.03). Use of radiation therapy did not improve overall survival, recurrence-free survival, or disease-specific survival. Patients who received four cycles or fewer of chemotherapy versus five to six cycles had similar overall survival, disease-specific survival, and recurrence-free survival. Conclusions: Post-operative chemotherapy or radiation in stage I high-risk endometrial cancer is not associated with improved cancer-specific or overall survival. More than four cycles of chemotherapy did not improve survival compared with four cycles or fewer.
MeSH term(s)	Chemotherapy, Adjuvant ; Endometrial Neoplasms/drug therapy ; Endometrial Neoplasms/radiotherapy ; Endometrial Neoplasms/surgery ; Female ; Humans ; Neoplasm Recurrence, Local/pathology ; Neoplasm Staging ; Radiotherapy, Adjuvant/methods ; Retrospective Studies
Language	English
Publishing date	2022-04-04
Publishing country	England
Document type	Journal Article
ZDB-ID	1070385-8
ISSN	1525-1438 ; 1048-891X
ISSN (online)	1525-1438
ISSN	1048-891X
DOI	10.1136/ijgc-2021-003087
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 3198: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (2.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

Details ▾
- See ZB MED holdings
- Order with fees

Article: Comparing the effects of continuous and discrete covariate mismeasurement, with emphasis on the dichotomization of mismeasured predictors.

Gustafson, Paul / Le Nhu, D

Biometrics

2002 Volume 58, Issue 4, Page(s) 878–887

Abstract: It is well known that imprecision in the measurement of predictor variables typically leads to bias in estimated regression coefficients. We compare the bias induced by measurement error in a continuous predictor with that induced by misclassification of ...

Abstract	It is well known that imprecision in the measurement of predictor variables typically leads to bias in estimated regression coefficients. We compare the bias induced by measurement error in a continuous predictor with that induced by misclassification of a binary predictor in the contexts of linear and logistic regression. To make the comparison fair, we consider misclassification probabilities for a binary predictor that correspond to dichotomizing an imprecise continuous predictor in lieu of its precise counterpart. On this basis, nondifferential binary misclassification is seen to yield more bias than nondifferential continuous measurement error. However, it is known that differential misclassification results if a binary predictor is actually formed by dichotomizing a continuous predictor subject to nondifferential measurement error. When the postulated model linking the response and precise continuous predictor is correct, this differential misclassification is found to yield less bias than continuous measurement error, in contrast with nondifferential misclassification, i.e., dichotomization reduces the bias due to mismeasurement. This finding, however, is sensitive to the form of the underlying relationship between the response and the continuous predictor. In particular, we give a scenario where dichotomization involves a trade-off between model fit and misclassification bias. We also examine how the bias depends on the choice of threshold in the dichotomization process and on the correlation between the imprecise predictor and a second precise predictor.
MeSH term(s)	Bias ; Data Interpretation, Statistical ; Humans ; Likelihood Functions ; Models, Statistical ; Neoplasms/etiology ; Neoplasms/pathology ; Regression Analysis ; Smoking/adverse effects ; Surveys and Questionnaires
Language	English
Publishing date	2002-12-19
Publishing country	United States
Document type	Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	213543-7
ISSN	0006-341X ; 0099-4987
ISSN	0006-341X ; 0099-4987
DOI	10.1111/j.0006-341x.2002.00878.x
Database	MEDical Literature Analysis and Retrieval System OnLINE

Full text online

Accessible to users with ZB MED library card

In stock of ZB MED Cologne/Königswinter

Zs.B 72: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾

Article ; Online: Accurate Distinction of Ovarian Clear Cell From Endometrioid Carcinoma Requires Integration of Phenotype, Immunohistochemical Predictions, and Genotype: Implications for Lynch Syndrome Screening.

Rodriguez, Monica / Kang, Eun Young / Farrington, Kyo / Cook, Linda S / Le, Nhu D / Karnezis, Anthony N / Lee, Cheng-Han / Nelson, Gregg S / Terzic, Tatjana / Lee, Sandra / Köbel, Martin

The American journal of surgical pathology

2021 Volume 45, Issue 11, Page(s) 1452–1463

Abstract: Ovarian clear cell carcinoma (OCCC) and ovarian endometrioid carcinoma (OEC) are both associated with endometriosis but differ in histologic phenotype, biomarker profile, and survival. Our objectives were to refine immunohistochemical (IHC) panels that ... ...

Abstract	Ovarian clear cell carcinoma (OCCC) and ovarian endometrioid carcinoma (OEC) are both associated with endometriosis but differ in histologic phenotype, biomarker profile, and survival. Our objectives were to refine immunohistochemical (IHC) panels that help distinguish the histotypes and reassess the prevalence of mismatch repair deficiency (MMRd) in immunohistochemically confirmed OCCC. We selected 8 candidate IHC markers to develop first-line and second-line panels in a training set of 344 OCCC/OEC cases. Interobserver reproducibility of histotype diagnosis was assessed in an independent testing cohort of 100 OCC/OEC initially without and subsequently with IHC. The prevalence of MMRd was evaluated using the testing cohort and an expansion set of 844 ovarian carcinomas. The 2 prototypical combinations (OCCC: Napsin A+/HNF1B diffusely+/PR-; OEC: Napsin A-/HNF1B nondiffuse/PR+) occurred in 75% of cases and were 100% specific. A second-line panel (ELAPOR1, AMACR, CDX2) predicted the remaining cases with 83% accuracy. Integration of IHC improved interobserver reproducibility (κ=0.778 vs. 0.882, P<0.0001). The prevalence of MMRd was highest in OEC (11.5%, 44/383), lower in OCCC (1.7%, 5/297), and high-grade serous carcinomas (0.7%, 5/699), and absent in mucinous (0/126) and low-grade serous carcinomas (0/50). All 5 MMRd OCCC were probable Lynch syndrome cases with prototypical IHC profile but ambiguous morphologic features: 3/5 with microcystic architecture and 2/5 with intratumoral stromal inflammation. Integration of first-line and second-line IHC panels increases diagnostic precision and enhances prognostication and triaging for predisposing/predictive molecular biomarker testing. Our data support universal Lynch syndrome screening in all patients with OEC when the diagnosis of other histotypes has been vigorously excluded.
MeSH term(s)	Biomarkers, Tumor/analysis ; Carcinoma, Endometrioid/chemistry ; Carcinoma, Endometrioid/genetics ; Carcinoma, Endometrioid/pathology ; Colorectal Neoplasms, Hereditary Nonpolyposis/chemistry ; Colorectal Neoplasms, Hereditary Nonpolyposis/genetics ; Colorectal Neoplasms, Hereditary Nonpolyposis/pathology ; DNA Mismatch Repair ; Diagnosis, Differential ; Female ; Genetic Predisposition to Disease ; Humans ; Immunohistochemistry ; Observer Variation ; Ovarian Neoplasms/chemistry ; Ovarian Neoplasms/genetics ; Ovarian Neoplasms/pathology ; Phenotype ; Predictive Value of Tests ; Reproducibility of Results
Chemical Substances	Biomarkers, Tumor
Language	English
Publishing date	2021-09-16
Publishing country	United States
Document type	Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	752964-8
ISSN	1532-0979 ; 0147-5185
ISSN (online)	1532-0979
ISSN	0147-5185
DOI	10.1097/PAS.0000000000001798
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 1356: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article: Combining data and simulated data for space–time fields: application to ozone

Zidek, James V / Le, Nhu D / Liu, Zhong

Environmental and ecological statistics. 2012 Mar., v. 19, no. 1

2012

Abstract: This paper presents a theory for modeling random environmental spatial-temporal fields that allows simulated data (numerical-physical model output) to be combined with measurements made at fixed monitoring sites. That theory involves Bayesian ... ...

Abstract	This paper presents a theory for modeling random environmental spatial-temporal fields that allows simulated data (numerical-physical model output) to be combined with measurements made at fixed monitoring sites. That theory involves Bayesian hierarchical models that provide temporal forecasts and spatial predictions along with appropriate credibility intervals. A by-product is a method for re-calibrating the simulated data to bring it into line with the measurements for certain applications. While the approach covers a broad domain of potential applications, this paper addresses a field of particular importance, ground level ozone concentrations over the eastern and central USA. A univariate model is developed and illustrated with hourly ozone fields. A multivariate alternative is also provided and illustrated with daily concentration fields. The forecasts and predictions they provide are compared with those from other approaches.
Keywords	models ; monitoring ; ozone ; prediction ; United States
Language	English
Dates of publication	2012-03
Size	p. 37-56.
Publishing place	Springer-Verlag
Document type	Article
ZDB-ID	2000906-9
ISSN	1573-3009 ; 1352-8505
ISSN (online)	1573-3009
ISSN	1352-8505
DOI	10.1007/s10651-011-0172-1
Database	NAL-Catalogue (AGRICOLA)

Full text online

Accessible to users with ZB MED library card

Order via subito

Details ▾
- Full text online
- Order with fees

Article: Time-Varying Markov Models for Binary Temperature Series in Agrorisk Management

Hosseini, Reza / Le, Nhu D / Zidek, James V

Journal of agricultural, biological and environmental statistics. 2012 June, v. 17, no. 2

2012

Abstract: This paper uses high-order categorical non-stationary Markov chains to model the occurrence of extreme temperature events, in particular frost days. These models can be applied to estimate: the probability that a given day in the future is a frost day ( ... ...

Abstract	This paper uses high-order categorical non-stationary Markov chains to model the occurrence of extreme temperature events, in particular frost days. These models can be applied to estimate: the probability that a given day in the future is a frost day (below zero); the probability that a given period is frost-free; the distribution of the length of the frost-free period. These quantities then can be used for pricing of weather derivatives. Several stationary and non-stationary high-order (yet parsimonious) Markov models are proposed and compared using AIC and BIC. Partial likelihood theory is used to estimate the parameters of these models. We show that optimal (in terms of AIC/BIC) non-stationary Markov models that have constant “Markov coefficients” (across the year) are not adequate to estimate the aforementioned probabilities. Therefore this paper develops Markov models with a time-varying periodic structure across the year. A challenge in fitting these models (by maximizing the partial likelihood) is the large number of parameters. The paper presents a method for overcoming this challenge; one that uses parametric fits to the logit of the nonparametric estimates of the seasonal transition probability curves to initialize the optim function in the R package. Satisfactory results are shown to obtain from this approach. The work is applied to temperature records for the Province of Alberta, Canada.
Keywords	frost ; models ; probability ; temperature ; Alberta
Language	English
Dates of publication	2012-06
Size	p. 283-305.
Publishing place	Springer-Verlag
Document type	Article
ZDB-ID	1324615-x
ISSN	1537-2693 ; 1085-7117
ISSN (online)	1537-2693
ISSN	1085-7117
DOI	10.1007/s13253-012-0090-1
Database	NAL-Catalogue (AGRICOLA)

Full text online

Accessible to users with ZB MED library card

In stock of ZB MED Bonn / Germany

Z 6481: Show issues

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾

Article ; Online: Ovarian Carcinoma Histotype: Strengths and Limitations of Integrating Morphology With Immunohistochemical Predictions.

Köbel, Martin / Luo, Li / Grevers, Xin / Lee, Sandra / Brooks-Wilson, Angela / Gilks, C Blake / Le, Nhu D / Cook, Linda S

International journal of gynecological pathology : official journal of the International Society of Gynecological Pathologists

2018 Volume 38, Issue 4, Page(s) 353–362

Abstract: Ovarian carcinoma histotypes are critical for research and patient management and currently assigned by a combination of histomorphology +/- ancillary immunohistochemistry (IHC). We aimed to validate the previously described IHC algorithm (Calculator of ... ...

Abstract	Ovarian carcinoma histotypes are critical for research and patient management and currently assigned by a combination of histomorphology +/- ancillary immunohistochemistry (IHC). We aimed to validate the previously described IHC algorithm (Calculator of Ovarian carcinoma Subtype/histotype Probability version 3, COSPv3) in an independent population-based cohort, and to identify problem areas for IHC predictions. Histotype was abstracted from cancer registries for eligible ovarian carcinoma cases diagnosed from 2002 to 2011 in Alberta and British Columbia, Canada. Slides were reviewed according to World Health Organization 2014 criteria, tissue microarrays were stained with and scored for the 8 COSPv3 IHC markers, and COSPv3 histotype predictions were calculated. Discordant cases for review and COSPv3 prediction were arbitrated by integrating morphology with IHC results. The integrated histotype (N=880) was then used to identify areas of inferior COSPv3 performance. Review histotype and integrated histotype demonstrated 93% agreement suggesting that IHC information revises expert review in up to 7% of cases. There was also 93% agreement between COSPv3 prediction and integrated histotype. COSPv3 errors predominated in 4 areas: endometrioid carcinoma (EC) versus clear cell (N=23), EC versus low-grade serous (N=15), EC versus high-grade serous (N=11), and high-grade versus low-grade serous (N=6). Most problems were related to Napsin A-negative clear cell, WT1-positive EC, and p53 IHC wild-type high-grade serous carcinomas. Although 93% of COSPv3 prediction accuracy was validated, some histotyping required integration of morphology with ancillary test results. Awareness of these limitations will avoid overreliance on IHC and misclassification of histotypes for research and clinical management.
MeSH term(s)	Algorithms ; Biomarkers, Tumor/metabolism ; Canada ; Cohort Studies ; Female ; Humans ; Immunohistochemistry ; Logistic Models ; Neoplasm Grading ; Ovarian Neoplasms/classification ; Ovarian Neoplasms/pathology ; Ovary/pathology ; Practice Guidelines as Topic ; Registries ; Tissue Array Analysis
Chemical Substances	Biomarkers, Tumor
Language	English
Publishing date	2018-05-25
Publishing country	United States
Document type	Journal Article
ZDB-ID	604859-6
ISSN	1538-7151 ; 0277-1691
ISSN (online)	1538-7151
ISSN	0277-1691
DOI	10.1097/PGP.0000000000000530
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 1814: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: Tattoos and Hematologic Malignancies in British Columbia, Canada.

Warner, Freda M / Darvishian, Maryam / Boyle, Terry / Brooks-Wilson, Angela R / Connors, Joseph M / Lai, Agnes S / Le, Nhu D / Song, Kevin / Sutherland, Heather / Woods, Ryan R / Bhatti, Parveen / Spinelli, John J

Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology

2020 Volume 29, Issue 10, Page(s) 2093–2095

Abstract: Background: Tattoos may cause a variety of adverse reactions in the body, including immune reactions and infections. However, it is unknown whether tattoos may increase the risk of lymphatic cancers such as non-Hodgkin lymphoma (NHL) and multiple ... ...

Abstract	Background: Tattoos may cause a variety of adverse reactions in the body, including immune reactions and infections. However, it is unknown whether tattoos may increase the risk of lymphatic cancers such as non-Hodgkin lymphoma (NHL) and multiple myeloma. Methods: Participants from two population-based case-control studies were included in logistic regression models to examine the association between tattoos and risk of NHL and multiple myeloma. Results: A total of 1,518 participants from the NHL study (737 cases) and 742 participants from the multiple myeloma study (373 cases) were included in the analyses. No statistically significant associations were found between tattoos and risk of NHL or multiple myeloma after adjusting for age, sex, ethnicity, education, body mass index, and family history. Conclusions: We did not identify any significant associations between tattoos and risk of multiple myeloma, NHL, or NHL subtypes in these studies. Impact: Though biologically plausible, tattoos were not associated with increased risk of NHL or multiple myeloma in this study. Future studies with greater detail regarding tattoo exposure may provide further insights.
MeSH term(s)	British Columbia ; Canada ; Female ; Hematologic Neoplasms/etiology ; Hematologic Neoplasms/physiopathology ; Humans ; Male ; Tattooing/adverse effects
Language	English
Publishing date	2020-07-22
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	1153420-5
ISSN	1538-7755 ; 1055-9965
ISSN (online)	1538-7755
ISSN	1055-9965
DOI	10.1158/1055-9965.EPI-20-0515
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 3693: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (2.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: Air pollution.

Le, Nhu D / Sun, Li / Zidek, James V

Chronic diseases in Canada

2010 Volume 29, Issue Suppl 2, Page(s) 144–163

Abstract: Toxic air pollutants are continuously released into the air supply. Various pollutants come from chemical facilities and small businesses, such as automobile service stations and dry cleaning establishments. Others, such as nitrogen oxides, carbon ... ...

Abstract	Toxic air pollutants are continuously released into the air supply. Various pollutants come from chemical facilities and small businesses, such as automobile service stations and dry cleaning establishments. Others, such as nitrogen oxides, carbon monoxide and other volatile organic chemicals, arise primarily from the incomplete combustion of fossil fuels (coal and petroleum) and are emitted from sources that include car exhausts, home heating and industrial power plants. Pollutants in the atmosphere also result from photochemical transformations; for example, ozone is formed when molecular oxygen or nitrogen interacts with ultraviolet radiation. An association between air pollution exposure and lung cancer has been observed in several studies. The evidence for other cancers is far less conclusive. Estimates of the population attributable risk of cancer has varied substantially over the last 40 years, reflecting the limitations of studies; these include insufficient information on confounders, difficulties in characterizing associations due to a likely lengthy latency interval, and exposure misclassification. Although earlier estimates were less than one percent, recent cohort studies that have taken into account some confounding factors, such as smoking and education amongst others, suggest that approximately 3.6% of lung cancer in the European Union could be due to air pollution exposure, particularly to sulphate and fine particulates. A separate cohort study estimated 5-7% of lung cancers in European never smokers and ex-smokers could be due to air pollution exposure. Therefore, while cigarette smoking remains the predominant risk factor, the proportion of lung cancers attributable to air pollution may be higher than previously thought. Overall, major weaknesses in all air-pollution-and-cancer studies to date have been inadequate characterization of long-term air pollution exposure and imprecise or no measurements of covariates. It has only been in the last decade that measurements to PM2.5 become more widely available. A key weakness of many studies is using fixed-site monitoring data and assuming everyone in a region had the same exposure. This ignores spatial variability, and does not take into account how individuals' exposures differ with pollution sources inside, outside, both at work, home and elsewhere. More recent efforts to model indicators of vehicular traffic, and residential distances to major roads and highway can allow for some of this spatial variability to be better controlled for. However, this still does not take into account differences in activity patterns. If the effect is small, these biases will compromise the ability to detect an association. In most situations, the resulting estimates tend to be biased toward the null (i.e., no effect). For misclassification of exposure the inability to adequately control for confounding variables may cause bias in either direction. Recent improvements in statistical methodology use measurements at fixed sites combined with residential histories to estimate individuals' cumulative exposures. They also recognize measurement errors associated with covariates in the analysis to improve estimates of effects. Other challenges include the fact that measurements of exposure and confounders can change over time and long term data are needed due to the anticipated latency interval between harmful exposures and development of cancer.
MeSH term(s)	Air Pollution/adverse effects ; Bias ; Environmental Exposure/analysis ; Humans ; Neoplasms/epidemiology ; Risk Assessment
Language	English
Publishing date	2010
Publishing country	Canada
Document type	Journal Article
ZDB-ID	1042130-0
ISSN	1481-8523 ; 0228-8699
ISSN (online)	1481-8523
ISSN	0228-8699
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 6492: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article: Comparing the Effects of Continuous and Discrete Covariate Mismeasurement, with Emphasis on the Dichotomization of Mismeasured Predictors

Gustafson, Paul / Le, Nhu D

Biometrics journal of the International Biometrics Society.. 2002 Dec., v. 58, no. 4

2002

Abstract	It is well known that imprecision in the measurement of predictor variables typically leads to bias in estimated regression coefficients. We compare the bias induced by measurement error in a continuous predictor with that induced by misclassification of a binary predictor in the contexts of linear and logistic regression. To make the comparison fair, we consider misclassification probabilities for a binary predictor that correspond to dichotomizing an imprecise continuous predictor in lieu of its precise counterpart. On this basis, nondifferential binary misclassification is seen to yield more bias than nondifferential continuous measurement error. However, it is known that differential misclassification results if a binary predictor is actually formed by dichotomizing a continuous predictor subject to nondifferential measurement error. When the postulated model linking the response and precise continuous predictor is correct, this differential misclassification is found to yield less bias than continuous measurement error, in contrast with nondifferential misclassification, i.e., dichotomization reduces the bias due to mismeasurement. This finding, however, is sensitive to the form of the underlying relationship between the response and the continuous predictor. In particular, we give a scenario where dichotomization involves a trade‐off between model fit and misclassification bias. We also examine how the bias depends on the choice of threshold in the dichotomization process and on the correlation between the imprecise predictor and a second precise predictor.
Keywords	biometry ; models ; regression analysis
Language	English
Dates of publication	2002-12
Size	p. 878-887.
Publishing place	Blackwell Publishing Ltd
Document type	Article
ZDB-ID	213543-7
ISSN	0099-4987 ; 0006-341X
ISSN	0099-4987 ; 0006-341X
DOI	10.1111/j.0006-341X.2002.00878.x
Database	NAL-Catalogue (AGRICOLA)

Full text online

Accessible to users with ZB MED library card

In stock of ZB MED Bonn / Germany

Z 58/144: Show issues
I/354: Show issues

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾

Article ; Online: The Super-Seniors Study: Phenotypic characterization of a healthy 85+ population.

Halaschek-Wiener, Julius / Tindale, Lauren C / Collins, Jennifer A / Leach, Stephen / McManus, Bruce / Madden, Kenneth / Meneilly, Graydon / Le, Nhu D / Connors, Joseph M / Brooks-Wilson, Angela R

PloS one

2018 Volume 13, Issue 5, Page(s) e0197578

Abstract: Background: To understand why some people live to advanced age in good health and others do not, it is important to study not only disease, but also long-term good health. The Super-Seniors Study aims to identify factors associated with healthy aging.!## ...

Abstract	Background: To understand why some people live to advanced age in good health and others do not, it is important to study not only disease, but also long-term good health. The Super-Seniors Study aims to identify factors associated with healthy aging. Methods: 480 healthy oldest-old 'Super-Seniors' aged 85 to 105 years and never diagnosed with cancer, cardiovascular disease, diabetes, dementia, or major pulmonary disease, were compared to 545 mid-life controls aged 41-54, who represent a group that is unselected for survival from late-life diseases. Health and lifestyle information, personal and family medical history, and blood samples were collected from all participants. Super-Seniors also underwent four geriatric tests. Results: Super-Seniors showed high cognitive (Mini-Mental State Exam mean = 28.3) and functional capacity (Instrumental Activities of Daily Living Scale mean = 21.4), as well as high physical function (Timed Up and Go mean = 12.3 seconds) and low levels of depression (Geriatric Depression Scale mean = 1.5). Super-Seniors were less likely to be current smokers than controls, but the frequency of drinking alcohol was the same in both groups. Super-Seniors were more likely to have 4 or more offspring; controls were more likely to have no children. Female Super-Seniors had a mean age of last fertility 1.9 years older than controls, and were 2.3 times more likely to have had a child at ≥ 40 years. The parents of Super-Seniors had mean ages of deaths of 79.3 years for mothers, and 74.5 years for fathers, each exceeding the life expectancy for their era by a decade. Conclusions: Super-Seniors are cognitively and physically high functioning individuals who have evaded major age-related chronic diseases into old age, representing the approximately top 1% for healthspan. The familiality of long lifespan of the parents of Super-Seniors supports the hypothesis that heritable factors contribute to this desirable phenotype.
MeSH term(s)	Activities of Daily Living ; Adult ; Age Factors ; Aged, 80 and over ; Canada ; Female ; Geriatric Assessment ; Health Status ; Humans ; Life Style ; Male ; Middle Aged ; Public Health Surveillance
Language	English
Publishing date	2018-05-24
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ISSN	1932-6203
ISSN (online)	1932-6203
DOI	10.1371/journal.pone.0197578
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

To top

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

Full text online

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

Full text online

More links

Kategorien

Order via subito

Full text online

More links

Kategorien

In stock of ZB MED Bonn / Germany

Order via subito

Inter-library loan at ZB MED

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

Full text online

More links

Kategorien

In stock of ZB MED Bonn / Germany

Order via subito

Inter-library loan at ZB MED

More links

Kategorien

Order via subito

Inter-library loan at ZB MED