LIVIVO - Search results -

Search results

Result 1 - 10 of total 85

Search options

Article ; Conference proceedings: Automatic MRI-based 3D Models of Hip Cartilage Using a 3D U-net-like Fully Convolutional Network for Improved Morphologic and Biochemical Analysis

Schmaranzer, F. / Helfenstein, R. / Zeng, G. / Lerch, T. D. / Siebenrock, K. / Tannast, M. / Zheng, G.

2019 Volume 23, Issue S 02

Event/congress	26th Annual Scientific Meeting of the European Society of Musculoskeletal Radiology (ESSR), Lisbon, Portugal, 2019-06-26
Language	English
Publishing date	2019-06-01
Publisher	Georg Thieme Verlag KG
Publishing place	Stuttgart ; New York
Document type	Article ; Conference proceedings
ZDB-ID	1360919-1
ISSN	1098-898X ; 1089-7860
ISSN (online)	1098-898X
ISSN	1089-7860
DOI	10.1055/s-0039-1692571
Database	Thieme publisher's database

In stock of ZB MED Cologne/Königswinter

Zs.A 4887: 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: Data and models determine treatment proposals--an illustration from meta-analysis.

Helfenstein, U

Postgraduate medical journal

2001 Volume 78, Issue 917, Page(s) 131–134

Abstract: A relevant problem in meta-analysis concerns the possible heterogeneity between trial results. If a test of heterogeneity is not significant the trials are often considered to be "homogeneous" and the individual trial results are replaced by an overall ... ...

Abstract	A relevant problem in meta-analysis concerns the possible heterogeneity between trial results. If a test of heterogeneity is not significant the trials are often considered to be "homogeneous" and the individual trial results are replaced by an overall mean effect size and its confidence interval ("equal effects model"). If the trials are heterogeneous the individual trial effect sizes are conserved ("fixed effects model"). In a more flexible approach ("random effects model"), each trial makes use of knowledge from the other trials so individual effect sizes are "shrunken" towards an overall mean effect size. The more flexible tool may be useful for doctors involved in a trial when the outcome of their individual trial differs markedly from the overall mean effect size. Where a particular trial result is opposite in direction to the overall mean result, a conflict may arise: should a new patient be treated with the new method or not? The more flexible position and a graphical comparison of the three approaches are likely to be helpful in guiding the decision. Applying different models to the same data may lead to apparently paradoxical results: an individual trial result may be interpreted to be beneficial or harmful depending on the choice of model.
MeSH term(s)	Decision Making ; Humans ; Meta-Analysis as Topic ; Models, Statistical ; Randomized Controlled Trials as Topic ; Reproducibility of Results
Language	English
Publishing date	2001-02-06
Publishing country	England
Document type	Journal Article ; Review
ZDB-ID	80325-x
ISSN	1469-0756 ; 0032-5473
ISSN (online)	1469-0756
ISSN	0032-5473
DOI	10.1136/pmj.78.917.131
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Ua VI Zs.340: 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: Box-Jenkins modelling in medical research.

Helfenstein, U

Statistical methods in medical research

1996 Volume 5, Issue 1, Page(s) 3–22

Abstract: Notifications of diseases, entries in a hospital, injuries due to accidents, etc., are frequently collected in fixed equally spaced intervals. Such observations are likely to be dependent. In environmental medicine, where series such as daily ... ...

Abstract	Notifications of diseases, entries in a hospital, injuries due to accidents, etc., are frequently collected in fixed equally spaced intervals. Such observations are likely to be dependent. In environmental medicine, where series such as daily concentrations of pollutants are collected and analysed, it is evident that dependence of consecutive measurements may be important. A high concentration of a pollutant today has a certain 'inertia', i.e. a tendency to be high tomorrow as well. Dependence of consecutive observations may be equally important when data such as blood glucose are recorded within a single patient. ARIMA models (autoregressive integrated moving average models, Box-Jenkins models), which allow the stochastic dependence of consecutive data to be modelled, have become well established in such fields as economics. This article reviews basic concepts of Box-Jenkins modelling. The methods are illustrated by applications. In particular, the following topics are presented: the ARIMA model, transfer function models (assessment of relations between time series) and intervention analysis (assessment of changes of time series).
MeSH term(s)	Data Collection ; Data Interpretation, Statistical ; Humans ; Models, Statistical ; Regression Analysis ; Research/statistics & numerical data ; Research Design/statistics & numerical data ; Stochastic Processes
Language	English
Publishing date	1996-03
Publishing country	England
Document type	Journal Article
ZDB-ID	1136948-6
ISSN	1477-0334 ; 0962-2802
ISSN (online)	1477-0334
ISSN	0962-2802
DOI	10.1177/096228029600500102
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 3564: 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: Air pollution and diseases of the respiratory tracts in pre-school children: A transfer function model.

Helfenstein, U / Ackermann-Liebrich, U / Braun-Fahrländer, C / Wanner, H U

Environmental monitoring and assessment

2013 Volume 17, Issue 2-3, Page(s) 147–156

Abstract: The purpose of the present statistical analysis was the assessment of the relation between time series of environmental factors and of frequencies of diseases of the respiratory system in pre-school children. During about one year, daily measurements of ... ...

Abstract	The purpose of the present statistical analysis was the assessment of the relation between time series of environmental factors and of frequencies of diseases of the respiratory system in pre-school children. During about one year, daily measurements of air pollutants and climatic variables were taken. During the same period of time two series of medical data were collected: (i) The daily relative number of pre-school children, exhibiting diseases of the respiratory tracts who either came to the outpatients' clinic of the children's hospital or were reported by paediatricians in Basle (ENTRIES). (ii) The daily relative frequency of symptoms of the respiratory tracts observed in a group of randomly selected pre-school children (SYMPTOMS).By means of transfer function models the relation between the two target variables and the 'explaining' variables was analysed. Several practical problems did arise: Choice of the appropriate transformation of the different series, interpretation of the crosscorrelation function using different methods of 'prewhitening', time splitting and nonstationarity of the crosscorrelation structure. In particular, it was found that after prewhitening the crosscorrelation function between the explanatory series SO2 and the response series SYMPTOMS changes with time. While during the 'winter period' an instantaneous relation between these two series (and to a lesser extent between NO2 and SYMPTOMS) was identified, no such relation was found for the other seasons.
Language	English
Publishing date	2013-11-14
Publishing country	Netherlands
Document type	Journal Article
ZDB-ID	782621-7
ISSN	1573-2959 ; 0167-6369
ISSN (online)	1573-2959
ISSN	0167-6369
DOI	10.1007/BF00399299
Database	MEDical Literature Analysis and Retrieval System OnLINE

Full text online

Accessible to users with ZB MED library card

In stock of ZB MED Bonn / Germany

Z 5186: 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 impact of competing stroke etiologies in patients with atrial fibrillation.

European stroke journal

2023 Volume 8, Issue 3, Page(s) 703–711

Abstract: Background: Data on the impact of competing stroke etiologies in stroke patients with atrial fibrillation (AF) are scarce.: Methods: We used prospectively obtained data from an observational registry (Novel-Oral-Anticoagulants-in-Ischemic-Stroke- ... ...

Abstract	Background: Data on the impact of competing stroke etiologies in stroke patients with atrial fibrillation (AF) are scarce. Methods: We used prospectively obtained data from an observational registry (Novel-Oral-Anticoagulants-in-Ischemic-Stroke-Patients-(NOACISP)-LONGTERM) of consecutive AF-stroke patients treated with oral anticoagulants. We compared the frequency of (i) the composite outcome of recurrent ischemic stroke (IS), intracerebral hemorrhage (ICH) or all-cause death as well as (ii) recurrent IS alone among AF-stroke patients with versus without competing stroke etiologies according to the TOAST classification. We performed cox proportional hazards regression modeling adjusted for potential confounders. Furthermore, the etiology of recurrent IS was assessed. Results: Among 907 patients (median age 81, 45.6% female), 184 patients (20.3%) had competing etiologies, while 723 (79.7%) had cardioembolism as the only plausible etiology. During 1587 patient-years of follow-up, patients with additional large-artery atherosclerosis had higher rates of the composite outcome (adjusted HR [95% CI] 1.64 [1.11, 2.40], Conclusion: In stroke patients with AF, causes other than cardioembolism as competing etiologies were common in index or recurrent IS. Concomitant presence of large-artery-atherosclerosis seems to indicate an increased risk for recurrences suggesting that stroke preventive means might be more effective if they also address competing stroke etiologies in AF-stroke patients. Clinical trial registration: NCT03826927.
MeSH term(s)	Humans ; Female ; Male ; Atrial Fibrillation/complications ; Brain Ischemia/complications ; Risk Factors ; Stroke/epidemiology ; Anticoagulants/therapeutic use ; Ischemic Stroke/chemically induced ; Atherosclerosis/complications
Chemical Substances	Anticoagulants
Language	English
Publishing date	2023-07-04
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2851287-X
ISSN	2396-9881 ; 2396-9873
ISSN (online)	2396-9881
ISSN	2396-9873
DOI	10.1177/23969873231185220
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article: The use of transfer function models, intervention analysis and related time series methods in epidemiology.

Helfenstein, U

International journal of epidemiology

1991 Volume 20, Issue 3, Page(s) 808–815

Abstract: In epidemiology, data often arise in the form of time series e.g. notifications of diseases, entries to a hospital, mortality rates etc. are frequently collected at weekly or monthly intervals. Usual statistical methods assume that the observed data are ... ...

Abstract	In epidemiology, data often arise in the form of time series e.g. notifications of diseases, entries to a hospital, mortality rates etc. are frequently collected at weekly or monthly intervals. Usual statistical methods assume that the observed data are realizations of independent random variables. However, if data which arise in a time sequence have to be analysed, it is possible that consecutive observations are dependent. In environmental epidemiology, where series such as daily concentrations of pollutants were collected and analysed, it became clear that stochastic dependence of consecutive measurements may be important. A high concentration of a pollutant today e.g. has a certain inertia i.e. a tendency to be high tomorrow as well. Since the early 1970s, time series methods, in particular ARIMA models (autoregressive integrated moving average models) which have the ability to cope with stochastic dependence of consecutive data, have become well established in such fields as industry and economics. Recently, time series methods are of increasing interest in epidemiology. Since these methods are not generally familiar to epidemiologists this article presents their basic concepts in a condensed form. This may encourage readers to consider the methods described and enable them to avoid pitfalls inherent in time series data. In particular, the following topics are discussed: Assessment of relations between time series (transfer function models). Assessment of changes of time series (intervention analysis), forecasting and some related time series methods.
MeSH term(s)	Epidemiologic Methods ; Epidemiology ; Forecasting/methods ; Humans ; Models, Theoretical
Language	English
Publishing date	1991-09
Publishing country	England
Document type	Journal Article
ZDB-ID	187909-1
ISSN	1464-3685 ; 0300-5771
ISSN (online)	1464-3685
ISSN	0300-5771
DOI	10.1093/ije/20.3.808
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 893: 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: Detecting hidden relations between time series of mortality rates.

Helfenstein, U

Methods of information in medicine

1990 Volume 29, Issue 1, Page(s) 57–60

Abstract: In the present report a method is described which may help to decide if a disease is influenced by an environmental factor which fluctuates in time: For each of two naturally arising subgroups of a population (such as males and females) an ARIMA model ( ... ...

Abstract	In the present report a method is described which may help to decide if a disease is influenced by an environmental factor which fluctuates in time: For each of two naturally arising subgroups of a population (such as males and females) an ARIMA model (autoregressive integrated moving average model) is identified. These models are used as filters to remove the autocorrelation in each series. If the resulting crosscorrelation function between the two filtered series shows a marked peak at time lag 0 this may indicate that such an environmental factor is present. The procedure is demonstrated using yearly data of mortality rates among the elderly.
MeSH term(s)	Aged ; Aged, 80 and over ; Environmental Pollution/adverse effects ; Female ; Humans ; Male ; Middle Aged ; Models, Biological ; Mortality ; Time Factors
Language	English
Publishing date	1990-01
Publishing country	Germany
Document type	Journal Article
ZDB-ID	3500-2
ISSN	0026-1270
ISSN	0026-1270
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 126: 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: When did a reduced speed limit show an effect? Exploratory identification of an intervention time.

Helfenstein, U

Accident; analysis and prevention

1990 Volume 22, Issue 1, Page(s) 79–87

Abstract: In a statistical analysis of accident data before and after a speed limit reduction, the time of the countermeasure is, of course, well known. Our understanding of the accident process may, however, be increased if we assume in a thought experiment that ... ...

Abstract	In a statistical analysis of accident data before and after a speed limit reduction, the time of the countermeasure is, of course, well known. Our understanding of the accident process may, however, be increased if we assume in a thought experiment that this time is unknown. We ask if the data themselves can tell us something about such a possible time. By means of time series of traffic accidents in Zurich before and after a speed limit reduction, different exploratory methods are presented to identify the "unknown" time of this measure. For most of the investigated series, the most likely time was found to lie in the three months before the true introduction. A possible explanation of this result may be that the media already informed the public before the countermeasure was actually introduced. This finding leads to an improved parsimonious intervention model which distinguishes between a possible "preintervention effect" and the usual "intervention effect."
MeSH term(s)	Accidents, Traffic/prevention & control ; Accidents, Traffic/statistics & numerical data ; Humans ; Models, Statistical ; Retrospective Studies ; Switzerland ; Time Factors
Language	English
Publishing date	1990-02
Publishing country	England
Document type	Journal Article
ZDB-ID	210223-7
ISSN	1879-2057 ; 0001-4575
ISSN (online)	1879-2057
ISSN	0001-4575
DOI	10.1016/0001-4575(90)90009-a
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 2461: 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: [No title information]

Helfenstein, U.

Zentralbl. Hygiene und Umweltmedizin

1996 Volume 198, Issue 5, Page(s) 383–393

Abstract: In der vorliegenden Studie wurde versucht, den Einfluss von Luftschadstoffen und anderen Umweltfaktoren auf die Haeufigkeit von Arztbesuchen wegen Atemwegserkrankungen nachzuweisen. Dazu dienten die Daten des Schweizerischen Sentinella-Systems aus einer ... ...

Institution	Hess-Str. 27e, CH-3097 Bern-Liebefeld Bundesamt fuer Gesundheitswesen
Abstract	In der vorliegenden Studie wurde versucht, den Einfluss von Luftschadstoffen und anderen Umweltfaktoren auf die Haeufigkeit von Arztbesuchen wegen Atemwegserkrankungen nachzuweisen. Dazu dienten die Daten des Schweizerischen Sentinella-Systems aus einer Periode von zwei Jahren. Im Mittel wurden woechentlich 16 Asthmafaelle und 9 Faelle von Bronchitis gemeldet, ausgedrueckt in Prozent aller Konsultationen waren dies 0.12% und 0.065%. Als Indikatoren fuer die Luftverschmutzung wurden Daten von SO2, NO2, Ozon und Schwebestaub herangezogen. Zusaetzlich wurden meteorologische Parameter wie Lufttemperatur und Luftdruck mit einbezogen, sowie die Auftretenszeiten der wichtigsten allergenen Pollen in der Schweiz: Gras, Birke und Beifuss. Diese Umweltparameter wurden ueber die Messstationen gemittelt oder aufsummiert, und die Autokorrelation in der Zeitreihe wurde beruecksichtigt. Mit der Analyse konnte jedoch kein Zusammenhang zwischen den gemeldeten Faellen von Asthma oder Exazerbation chronischer Bronchitis und der Luftverschmutzung oder anderen Umweltdaten nachgewiesen werden. Dieses Resultat widerspricht teilweise der Literatur, koennte jedoch durch die wegen Selbstmedikation niedrige Anzahl der Meldefaelle erklaert werden, sowie durch die ungenaue Bestimmung der wirklichen Exposition.
Keywords	Bronchialasthma ; Bronchitis ; Chronisch ; Luftverunreinigung ; Umwelt ; Schwefeldioxid ; Stickstoffdioxid ; Ozon ; Pollen ; Schweiz ; Arztbesuch ; Haeufigkeit ; Einfluss
Language	English
Document type	Article
Database	Social Medicine (SOMED)

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: Zeitreihenanalyse eines Präventionseffektes am Beispiel des Unfallgeschehens in Zürich vor und nach Tempo 50.

Helfenstein, U

Sozial- und Praventivmedizin

1987 Volume 32, Issue 6, Page(s) 305–309

Abstract: In the evaluation of the effect of preventive measures data often arise at fixed time intervals and it is likely that successive observations are stochastically dependent. By means of the example of the "possible reduction of traffic injuries after the ... ...

Title translation	Time series analysis of the influence of prevention using the example of the occurrence of accidents in Zurich before and after Tempo 50.
Abstract	In the evaluation of the effect of preventive measures data often arise at fixed time intervals and it is likely that successive observations are stochastically dependent. By means of the example of the "possible reduction of traffic injuries after the introduction of a speed limitation (50 km/h) in Zurich" it is shown how time series methods can help to assess the efficiency of such measures. For the series before the intervention a statistical model is identified which describes the probability structure of the series. This model is used to forecast the course of the series one would expect when no intervention takes place. The forecast and the actual series are then plotted in the same figure and the difference is analysed with a test. In addition to that the magnitude of the effect and its standard error are estimated (intervention analysis). The series "numbers of accidents with injuries" showed after the intervention a yearly reduction of approximately 250 accidents (14%) with a corresponding standard error of 30. The reduction is markedly less pronounced in the series "number of seriously injured persons" than in the series "number of slightly injured persons".
MeSH term(s)	Accidents, Traffic/prevention & control ; Humans ; Methods ; Models, Theoretical ; Stochastic Processes ; Switzerland ; Time Factors ; Urban Population
Language	German
Publishing date	1987
Publishing country	Switzerland
Document type	Comparative Study ; English Abstract ; Journal Article
ZDB-ID	125375-x
ISSN	1420-911X ; 0303-8408
ISSN (online)	1420-911X
ISSN	0303-8408
DOI	10.1007/bf02078167
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 843: 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

To top

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

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

Kategorien

Inter-library loan at ZB MED

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito