Estimation of mortality rate ratios for chronic conditions with misclassification of disease status at death.

Estimation of mortality rates and mortality rate ratios (MRR) of diseased and non-diseased individuals is a core metric of disease impact used in chronic disease epidemiology. Estimation of mortality rates is often conducted through retrospective linkage of information from nationwide surveys such as the National Health Interview Survey (NHIS) and death registries. These surveys usually collect information on disease status during only one study visit.

Is it all due to peers? The influence of peers on children's snack purchase decisions.

The objective of this study is to examine whether the presence of peers has an impact on children's snack purchasing decisions. In particular, the research analyzes whether the company of a classmate or friend influences children's brand awareness and price perception, and how these factors affect their snack purchases. An incentive-based discrete choice experiment was conducted with snacks varying in price, brand, and healthiness, using the presence or absence of peers as a between-subject treatment.

Sources, Occurrence and Characteristics of Fluorescent Biological Aerosol Particles Measured Over the Pristine Southern Ocean.

In this study, we investigate the occurrence of primary biological aerosol particles (PBAP) over all sectors of the Southern Ocean (SO) based on a 90-day data set collected during the Antarctic Circumnavigation Expedition (ACE) in austral summer 2016-2017. Super-micrometer PBAP (1-16 µm diameter) were measured by a wide band integrated bioaerosol sensor (WIBS-4). Low (3σ) and high (9σ) fluorescence thresholds are used to obtain statistics on fluorescent and hyper-fluorescent PBAP, respectively.

Five-year outcome in 18 010 patients from the German Aortic Valve Registry.

Objectives: To determine the 5-year outcome in patients treated by isolated transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (sAVR)-a prospective observational cohort study.

Methods: A total of 18 010 patients were included (n = 8942 TAVI and n = 9068 sAVR) in the German Aortic Valve Registry (GARY) who were treated in 2011 and 2012 at 92 sites in central Germany. Eligible patients with TAVI and sAVR were matched using propensity scores in a nearest-neighbour approach.

Impact of new pacemaker implantation following surgical and transcatheter aortic valve replacement on 1-year outcome.

Objectives: The purpose of this study was to evaluate the incidence of new pacemaker implantation (NPMI) after surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR), and investigate its influence on 1-year mortality.

Methods: Patients who were enrolled in 'The German Aortic Valve Registry' undergoing isolated TAVR or SAVR between 2011 and 2015 were analysed. The rate of NPMI was analysed for both groups and multivariable Cox regression analysis was performed to investigate the possible independent association between NPMI and 1-year mortality.

Longitudinal changes in subchondral bone structure as assessed with MRI are associated with functional outcome after high tibial osteotomy.

Objectives: The primary objective of this study was to evaluate the effects of high tibial osteotomy (HTO) on subchondral bone structure assessed with magnetic resonance (MR)-based trabecular bone imaging and the correlations of these effects with functional outcome and clinical symptoms.

Methods: Patients with varus malalignment (6.2±2.

Patients at Intermediate Surgical Risk Undergoing Isolated Interventional or Surgical Aortic Valve Implantation for Severe Symptomatic Aortic Valve Stenosis.

Background: Transcatheter aortic valve replacement (TAVR) is increasingly being used for treatment of severe aortic valve stenosis in patients at intermediate risk for surgical aortic valve replacement (SAVR). Currently, real-world data comparing indications and clinical outcomes of patients at intermediate surgical risk undergoing isolated TAVR with those undergoing SAVR are scarce.

Methods: We compared clinical characteristics and outcomes of patients with intermediate surgical risk (Society of Thoracic Surgeons score 4%-8%) who underwent isolated TAVR or conventional SAVR within the prospective, all-comers German Aortic Valve Registry.

Rapid Deployment Versus Conventional Bioprosthetic Valve Replacement for Aortic Stenosis.

Background: Surgical aortic valve replacement using conventional biological valves (CBVs) is the standard of care for treatment of old patients with aortic valve disease. Recently, rapid deployment valves (RDVs) have been introduced.

Objectives: The purpose of this study was to report the nationwide German experience concerning RDVs for treatment of aortic valve stenosis and provide a head-to-head comparison with CBVs.

Children's purchase behavior in the snack market: Can branding or lower prices motivate healthier choices?

Background: Children's dietary-related diseases and their associated costs have expanded dramatically in many countries, making children's food choice a policy issue of increasing relevance. As children spend a considerable amount of money on energy-dense, nutrient-poor (EDNP) products, a better understanding of the main drivers of children's independent food purchase decisions is crucial to move this behavior toward healthier options.

Objective: The objective of the study is to investigate the role of branding and price in motivating children to choose healthier snack options.

Impact of quality of life (QoL) on glycemic control (HbA1c) among adolescents and emerging adults with long-duration type 1 diabetes: A prospective cohort-study.

Objective: To evaluate the impact of self-reported chronic-generic and condition-specific quality of life (QoL) on glycemic control among adolescents and emerging adults with long-duration type 1 diabetes (T1D) in a longitudinal design.

Methods: The database used was a nationwide cohort study of patients with ≥10 years T1D duration at baseline in Germany. The baseline questionnaire survey was conducted in 2009-2010, the follow-up survey in 2012-2013; additional clinical data of routine care procedures were linked.

Quality of Life After Transcatheter Aortic Valve Replacement: Prospective Data From GARY (German Aortic Valve Registry).

Objectives: This study sought to analyze health-related quality-of-life (HrQoL) outcomes of patients undergoing transcatheter aortic valve replacement (TAVR) based on data from GARY (German Aortic Valve Registry).

Background: Typically, patients currently referred for and treated by TAVR are elderly with a concomitant variable spectrum of multiple comorbidities, disabilities, and limited life expectancy. Beyond mortality and morbidity, the assessment of HrQoL is of paramount importance not only to guide patient-centered clinical decision-making but also to judge this new treatment modality in this high-risk patient population.

Surveillance of the Incidence of Non-Communicable Diseases (NCDs) with Sparse Resources: A Simulation Study Using Data from a National Diabetes Registry, Denmark, 1995-2004.

We propose two new methods to estimate secular trends in the incidence of a chronic disease from a series of prevalence studies and mortality data. One method is a direct inversion formula, the second method is a least squares estimation. Both methods are validated in a simulation study based on data from a diabetes register.

No adverse effect of outdoor air pollution on HbA1c in children and young adults with type 1 diabetes.

Background: Evidence is growing that air pollutants deteriorate glucose metabolism and insulin sensitivity by oxidative stress and inflammation. This might affect HbA1c levels and insulin requirements in type 1 diabetes. There are no data available on this association.

Development and demonstration of a state model for the estimation of incidence of partly undetected chronic diseases.

Background: Estimation of incidence of the state of undiagnosed chronic disease provides a crucial missing link for the monitoring of chronic disease epidemics and determining the degree to which changes in prevalence are affected or biased by detection.

Methods: We developed a four-part compartment model for undiagnosed cases of irreversible chronic diseases with a preclinical state that precedes the diagnosis. Applicability of the model is tested in a simulation study of a hypothetical chronic disease and using diabetes data from the Health and Retirement Study (HRS).

A comparative study of prevalence-based incidence estimation techniques with application to dementia data in Germany.

Dementia is becoming a major health burden, which is mainly due to the increasing life expectancy in many developed countries. To describe the disease progression of individuals, multistate models are generally appropriate tools. These models allow the individuals to move along a path consisting of a finite number of disease states.

Change rates and prevalence of a dichotomous variable: simulations and applications.

A common modelling approach in public health and epidemiology divides the population under study into compartments containing persons that share the same status. Here we consider a three-state model with the compartments: A, B and Dead. States A and B may be the states of any dichotomous variable, for example, Healthy and Ill, respectively.

A new relation between prevalence and incidence of a chronic disease.

In 1991 Keiding published a relation between the age-specific prevalence and incidence of a chronic disease (in Age-specific incidence and prevalence: a statistical perspective. J. Roy.

Lexis diagram and illness-death model: simulating populations in chronic disease epidemiology.

Chronic diseases impose a tremendous global health problem of the 21st century. Epidemiological and public health models help to gain insight into the distribution and burden of chronic diseases. Moreover, the models may help to plan appropriate interventions against risk factors.

The intermediates take it all: asymptotics of higher criticism statistics and a powerful alternative based on equal local levels.

The higher criticism (HC) statistic, which can be seen as a normalized version of the famous Kolmogorov-Smirnov statistic, has a long history, dating back to the mid seventies. Originally, HC statistics were used in connection with goodness of fit (GOF) tests but they recently gained some attention in the context of testing the global null hypothesis in high dimensional data. The continuing interest for HC seems to be inspired by a series of nice asymptotic properties related to this statistic.

Age- and time-dependent model of the prevalence of non-communicable diseases and application to dementia in Germany.

We derive a partial differential equation (PDE) that models the age-specific prevalence of a disease as a function of the incidence, remission and mortality rates. The main focus is on non-communicable diseases (NCDs), although the PDE is not restricted to NCDs. As an application of the PDE, the number of persons with dementia in Germany until the year 2050 is estimated based on German incidence data and official population projections.

Alignment does not influence cartilage T2 in asymptomatic knee joints.

Purpose: To investigate whether the static knee alignment affects articular cartilage ultrastructures when measured using T2 relaxation among asymptomatic subjects.

Methods: Both knee joints (n = 96) of 48 asymptomatic volunteers (26 females, 22 males; 25.4 ± 1.

Age of onset in chronic diseases: new method and application to dementia in Germany.

Background: Age of onset is an important outcome to characterize a population with a chronic disease. With respect to social, cognitive, and physical aspects for patients and families, dementia is especially burdensome. In Germany, like in many other countries, it is highly prevalent in the older population and imposes enormous efforts for caregivers and society.

Identification of a multistate continuous-time nonhomogeneous Markov chain model for patients with decreased renal function.

Objectives: Markov chain models are frequently used to study the clinical course of chronic diseases. The aim of this article is to adopt statistical methods to describe the time dynamics of chronically ill patients when 2 kinds of data sets--fully and partially observable data are available.

Model: We propose a 6-state continuous-time Markov chain model for the progression of chronic kidney disease (CKD), where little is known about the transitions between the disease stages.

Deriving age-specific incidence from prevalence with an ordinary differential equation.

This article describes new relationships between the age-specific incidence of, the prevalence of and mortality from a chronic disease. We express these relationships in terms of an ordinary differential equation and form the methodological basis for a novel approach to estimating incidences from age-specific prevalence data. We examine practical aspects of the relationships and a comparison with a known stochastic method in a simulation study.