Open Access

Abstract Aims To demonstrate the attitudes of general practitioners (GPs), nurses, persons with dementia, and caregiver towards suitable tasks and qualification needs for and the acceptance and impact of advanced nursing roles in German dementia primary care. Design Observational study using a questionnaire survey with 225 GPs, 232 nurses, 211 persons with dementia, and 197 caregivers, conducted between December 2017–August 2018. Methods A questionnaire was generated that includes specific assessment, prescription, and monitoring tasks of advanced nursing roles in dementia primary care as well as qualification requirements for and the acceptance and the impact of advanced nursing roles. Data were analysed using descriptive statistics. Group differences were assessed using the Fisher's exact test. Results Advanced nursing roles were highly appreciated across all groups. Assessment and monitoring tasks were rated as highly suitable, and prescription authorities as moderately suitable. Nurses felt less confident in assessment and monitoring, but more confident in prescribing as practitioners expected. Patients and caregivers would appreciate a takeover of tasks by nurses; nurses and practitioners preferred a delegation. A dementia‐specific qualification was rated as best suitable for advanced nursing roles, followed by ‘no specific qualification’ if medical tasks that only can be carried out by practitioners were delegated and an academic degree if tasks were substituted. Advanced nursing roles were rated as beneficial, strengthening the confidence in nursing care and improving the cooperation between professionals and the treatment. Practitioners assumed that advanced nursing roles would improve job satisfaction of nurses, which was not confirmed by nurses. Conclusion There is an extended consensus towards the enlargement of advanced nursing roles, represented by high endorsement, acceptance, and willingness to reorganize tasks. Impact Results debunk the common notion that German practitioners would be reluctant towards advanced nursing roles and a takeover of current practitioner tasks, supporting the implementation of advanced nursing roles in Germany.

Trade of cattle between farms forms a complex trade network. We investigate partitions of this network for cattle trade in Germany. These partitions are groups of farms with similar properties and they are inferred directly from the trade pattern between farms. We make use of a rather new method known as stochastic block modeling (SBM) in order to divide the network into smaller units. SBM turns out to outperform the more established community detection method in the context of disease control in terms of trade restriction. Moreover, SBM is also superior to geographical based trade restrictions and could be a promising approach for disease control.

This study aims to analyze psychometric properties and validity of the Compulsive Internet Use Scale (CIUS) and the Internet Addiction Test (IAT) and, second, to determine a threshold for the CIUS which matches the IAT cut-off for detecting problematic Internet use. A total of 292 subjects with problematic or pathological gambling (237 men, 55 women) aged 14-63 years and with private Internet use for at least 1 h per working or weekend day were recruited via different recruitment channels. Results include that both scales were internally consistent (Cronbach's α = 0.9) and had satisfactory convergent validity (r = 0.75; 95% CI 0.70-0.80). The correlation with duration of private Internet use per week was significantly higher for the CIUS (r = 0.54) compared to the IAT (r = 0.40). Among all participants, 25.3% were classified as problematic Internet users based on the IAT with a cut-off ≥40. The highest proportion of congruent classified cases results from a CIUS cut-off ≥18 (sensitivity 79.7%, specificity 79.4%). However, a higher cut-off (≥21) seems to be more appropriate for prevalence estimation of problematic Internet use.

Background: Sedentary behavior (SB) is a modifiable behavior with increasing prevalence worldwide. There is emerging evidence that time spend in SB and the manner in which SB is accumulated over time is associated with cardiovascular and cardiometabolic health. The requirement for SB data to be accurately measured is minimization, or at least accurate quantification of human-related sources of measurement errors such as accelerometer measurement reactivity (AMR). The present thesis was to examine SB and their associations with cardiovascular and cardiometabolic health, and to focus on challenges related to the assessment of SB. The first aim of the thesis was to identify patterns of SB describing how individuals accumulate their time spend in SB day-by-day over one week, and to examine how these patterns are associated with cardiorespiratory fitness as a marker for cardiovascular health (paper 1). The second aim of the thesis was to examine the multiple types of SB, and how this is associated with a clustered cardiometabolic risk score (CMRS; paper 2). The third aim of the thesis was to examine AMR and the reproducibility in SB and physical activity (PA) in two measurement periods, and to quantify AMR as a confounder for the estimation of the reproducibility of SB and PA data (paper 3). Methods: The three papers were based on data of two different studies. For study 1, 1165 individuals aged 40 to 75 years were recruited in three different settings. Among these, 582 participated in a cardiovascular risk factor screening program including cardiopulmonary exercise testing. For the analyses of paper 1, 170 participants were eligible, agreed to wear an accelerometer, fulfilled the wearing regime, and completed the study period by wearing the accelerometer for seven consecutive days. Patterns in accelerometer data were classified based on time spent in SB per day applying growth mixture modeling. Model‐implied class‐specific peak oxygen uptake (VO2peak) means were compared using adjusted equality test of means (paper 1). The underlying study of paper 2 and 3 were based on data of a pilot study aiming to investigate the feasibility of a brief tailored letter intervention to increase PA and to reduce SB during leisure time. Among the individuals who agreed to be contacted again in study 1, a random sample of those aged between 40 and 65 years was drawn. Of those, 175 attended in a cardiovascular examination program. Assessment included giving blood sample, standardized measurement of blood pressure, waist circumference, body weight, and height at baseline, and after twelve months. Further, they agreed to complete a paper-pencil questionnaire on SB (Last 7-d Sedentary Behavior Questionnaire, SIT-Q-7d) and PA (International Physical Activity Questionnaire, IPAQ), and to receive seven-day accelerometery at baseline, and after 12 months. In addition, self-administered assessments were conducted at months one, three, four, and six after baseline. Only individuals of a random subsample (= intervention group) received up to three letters tailored to their self-reported SB and PA at months one, three, and four. For paper 2, associations between SBs and a clustered cardiometabolic risk score (CMRS) were analyzed using linear as well as quantile regression. To account for missing values at baseline, multiple imputations using chained equations were performed resulting in a total sample of 173 participants. Paper 3 comprised data of 136 individuals who participated at the baseline and twelve months assessments, and fulfilled the wearing regime. AMR was examined using latent growth modeling in each measurement period. Intraclass correlations (ICC) were calculated to examine the reproducibility of SB and PA data using two-level mixed-effects linear regression analyses. Results: Results of paper 1 revealed four patterns of SB: 'High, stable', 'Low, increase', 'Low, decrease', and 'High, decrease'. Persons in the class 'High, stable' had significantly lower VO2peak values (M = 25.0 mL/kg/min, SD = 0.6) compared to persons in the class 'Low, increase' (M = 30.5 mL/kg/min, SD = 3.6; p = 0.001), in the class 'Low, decrease' (M = 30.1 mL/kg/min, SD = 5.0; p = 0.009), and in the class High, decrease' (M = 29.6 mL/kg/min, SD = 5.9; p = 0.032), respectively. No differences among the other classes were found. In paper 2, results revealed that the only factor positively associated with a CMRS in all regression models was watching television. Depending on the regression analysis approach used, other leisure-time SBs showed inconsistent (using a computer), or no associations (reading and socializing) with a CMRS. In paper 3, results revealed that time spent in SB increased (baseline: b = 2.3 min/d; after 12 months: b = 3.8 min/d), and time spent in light PA decreased (b = 2.0 min/day; b = 3.3 min/d). However, moderate-to-vigorous PA remained unchanged. Accelerometer wear time was reduced (b = 4.6 min/d) only at baseline. The ICC coefficients ranged from 0.42 (95% CI = 0.29 - 0.57) for accelerometer wear time to 0.70 (95% CI = 0.61 - 0.78) for moderate-to-vigorous PA. None of the regression models identified a reactivity indicator as a confounder for the reproducibility of SB and PA data. Conclusions: The present thesis highlights SB in the field of cardiovascular and cardiometabolic research that have implications for future research. Individuals sit for different purposes and durations in multiple life domains, and the time spent in SB is accumulated in different patterns over time. Therefore, research should consider the fact that SB is embedded in an individual's daily life routine, hence might have differential effects on cardiovascular and cardiometabolic health. Further, methodological aspects have to be considered when dealing with SB. In order to detect how SB is 'independently' associated to an individual's health, an accurate measurement of SB is fundamental. Therefore, human-related sources of bias such as AMR should be taken into account when either planning studies or when interpreting data drawn from analysis of SB data.

Background: Physical inactivity is one of the main risk factors for cardiovascular disease, which remains a major cause of death in Germany and around the globe. Thus, investigating prevalences, population trends, high-risk groups, and intervention effects of physical activity (PA) and sedentary time (ST) is highly relevant to public health. To receive reliable data, a key issue in research is to apply an appropriate study design including the carefully considered use of assessments. Otherwise, bias to PA and ST data may be introduced. The present thesis investigates three often overlooked issues related to the impact of measurement on PA and ST research data. The first aim was to examine whether mere measurement alters PA and ST over the course of twelve months (study 1). The second aim was to identify potential socio-demographic and cardiometabolic moderators of the mere-measurement effect (study 2). The third aim was to present design, protocol, and preliminary results of an interim analysis of a randomized controlled trial (RCT) aiming to test whether a video demonstration of PA intensity levels reduces the lack of agreement between self-reported and objectively measured PA (study 3). Methods: Studies 1 and 2 were based on data of a trial to test the feasibility of a brief tailored letter intervention to increase PA and to reduce ST during leisure time. Among a sample of subjects with no history of myocardial infarction, stroke, or vascular interventions, a number of 175 individuals aged 40 to 65 years participated in the study. At baseline, participants received standardized measurement of blood pressure and waist circumference, blood sample taking, and seven-day accelerometry. At baseline and after one, six, and twelve months, participants completed the International Physical Activity Questionnaire (IPAQ). A random subsample received a brief tailored letter intervention at months one, three, and four. A number of 153 participants were included in study 1 using all available data across 12 months. Changes in PA and ST were analyzed using latent growth modeling. For study 2, baseline and one-month follow-up data of 175 participants were used. Dependence of one-month changes in PA and ST on socio-demographic and cardiometabolic variables was analyzed using linear regression models. In study 3, individuals aged between 40 and 75 years were recruited at a shopping mall in Greifswald, Germany. Participants received seven-day accelerometry and were invited to the cardiovascular examination center of the University Medicine Greifswald. After random allocation to experimental and control group, they completed the selfadministered IPAQ – Short Form via tablet-computer. The experimental group additionally received a video demonstration of PA intensity levels before answering the questionnaire. A number of 131 participants were analyzed to receive preliminary results of an interim analysis in order to verify the presumptions made for the a priori power calculation and to decide on early stopping of the study. The difference between the study groups in the agreement between self-reported and accelerometer-based PA was analyzed using a two-sample t-test. Results: In study 1, results revealed no change in leisure-time PA, an increase in transportrelated PA (p = .023), and a tendency towards a reduction of ST (p = .060) between baseline and one-month assessment. Further, ST decreased between six and twelve months (p = .037). Time trends of the intervention group did not differ significantly from those of the assessment-only group. Results of study 2 revealed that men increased transport-related PA more than women (p = .031) and men with higher triglycerides increased transport-related PA less than men with lower triglycerides (p = .043). Men with higher systolic blood pressure reduced ST more than those with lower systolic blood pressure (p = .028). However, this linear association ceased to exist at a level of approximately 145 mmHg. A similar relationship was found for glycated hemoglobin and ST in men. In study 3, preliminary results of the interim analysis revealed a lower formal mean difference in the video group (M = 21.8 min/day, SD = 108.9) compared to the control group (M = 41.0 min/day, SD = 117.4, t(129) = 0.97, p = .166). The p-value lay between the significance (p < .010) and futility (p > .269) boundaries of the test simulations. Conclusions: Results of the present thesis have three implications for considering the impact of PA and ST assessments in cardiovascular research. First, mere-measurement effects within a feasibility trial were found in transport-related PA and ST suggesting to interfere with potential intervention effects. Thus, measurement effects should be considered when planning studies and interventions and when interpreting outcomes. Second, male sex and more favorable triglycerides levels in men were associated with a higher increase of transportrelated PA whereas worse health in men was associated with a higher reduction of ST. Thus, using the mere-measurement effect for prevention purposes may require researchers and practitioners to tailor PA and ST intervention components to individuals’ health condition. Third, the design and protocol of the RCT seems appropriate to test the effect of a novel video on the gap between self-reported and accelerometer-based PA. Preliminary results point to the efficacy of the video.

Hintergrund: Die zunehmende Impfkritik in bestimmten Bevölkerungskreisen wird in Zusammenhang mit der zunehmenden Verbreitung von Komplementärmedizin gebracht. Homöopathie ist einer der stärksten Vertreter unter der wachsenden Komplementär-Medizin. Besonders in der Pädiatrie, wo die meisten Impfungen durchgeführt werden, wird Homöopathie vermehrt eingesetzt. Eine Umfrage aus dem Jahre 1996 zeigte erstmals, dass entgegen der öffentlichen Meinung homöopathische Ärzte in Deutschland keine entschiedenen Impfgegner sind, aber durchaus kritischer und individueller beim Impfen vorgehen. Methodik: In der vorliegenden Arbeit werden Impfeinstellung und Impfverhalten unter niedergelassenen Pädiatern in ganz Deutschland untersucht. Hierbei werden Pädiater mit und ohne Zusatzbezeichnung Homöopathie gegenübergestellt. Mittels einer repräsentativen Querschnittuntersuchung wurden im Jahre 2006/2007 50 % (N=3019) aller niedergelassenen Pädiater aus ganz Deutschland per Post (Zufallsstichprobe) zum Thema Impfen befragt. Ergänzend wurden zeitgleich 245 homöopathisch orientierte Pädiater in die anonymisierte Befragung eingeschlossen. Das Instrument wurde zuvor in einer Pilotstudie unter 200 deutschen Pädiatern evaluiert. Die Auswahl der Pädiater erfolgte über Adressverzeichnisse der Kassenärztlichen Vereinigungen und Ärztekammern der verschiedenen Bundesländer, sowie zusätzlich über den Deutschen Zentralverein für homöopathische Ärzte (DZVhÄ) und der Karl und Veronica Carstens (KVC)-Stiftung um eine möglichst große Vergleichsgruppe an homöopathischen Pädiatern zu erhalten. Die Rückläufe der Zufallsziehung, der zusätzlich homöopathischen Pädiater und der Pilotstudie wurden für die Auswertung gepoolt. Für einen Vergleich wurden mittels 6 (Teil)-Fragen des Erhebungsinstrumentes Pädiater mit und ohne Schwerpunkt-/Zusatzbezeichnung Homöopathie differenziert. Letztere wurden zusätzlich unterschieden in Pädiater, die Homöopathie oder eine andere alternative/komplementäre Medizin anwenden oder rein konventionelle Medizin betreiben. Das Impfverhalten wurde im Hinblick auf das Einhalten der STIKO-Empfehlungen anhand von 3 Fragen des Erhebungsinstrumentes als Mittelwert-Score operationalisiert:1. Impfen Sie nach dem empfohlenen Impfkalender der STIKO? 2. Wie würden Sie eigene minderjährige Kinder Impfen? 3. Ab welchem Alter empfehlen Sie in der Regel die erste Durchführung von Impfungen? Um die Impfeinstellung zu operationalisieren, wurden die skalierten Positionierungen zu 8 vorgegebenen Meinungen zum Impfen zu einem Mittelwert-Score verrechnet. Der Einfluss folgender relevanter Variablen auf Impfeinstellung und Impfverhalten wurde mit einer multivariablen linearen Regression untersucht: Alter, Geschlecht, Ort der Niederlassung, Anteil an Privatpatienten und Zusatzbezeichnung Homöopathie. Für einen Vergleich mit den Studienergebnissen von 1996 wurde ein Impfkritiker-Index erstellt. Ergebnisse und Diskussion: Mit insgesamt 3464 angeschriebenen niedergelassenen Pädiatern (über 50 % aller niedergelassenen Pädiater aus jedem Bundesland) handelt es sich um die bisher größte bundesweite Studie zum Thema Impfen. Die Responserate ist mit insgesamt ca. 67 % überdurchschnittlich hoch, was ein großes Interesse zum Impfthema vermuten lässt. Vor dem Hintergrund einer weitestgehend vollständigen und aktuellen Praxis-Adress-Datenbasis kann diese Studie als deutschlandweit repräsentativ angesehen werden. Die Ergebnisse dieser Arbeit sind trotz leichter methodisch bedingter Einschränkungen in der Konstruktion der Stichprobe einmalig und aussagekräftig. Pädiater mit und ohne Zusatzbezeichnung Homöopathie unterscheiden sich im Hinblick auf ihre Impfeinstellung und ihr Impfverhalten (orientiert an den STIKO-Empfehlungen) signifikant. Die überwiegend positive, aber kritische Haltung zum Impfen unter homöopathischen Pädiatern ähnelt den Ergebnissen von P. Lehrke von 1996. Das Vorurteil „Homöopathen seien Impfgegner“ konnte für Kinderärzte aussagekräftig widerlegt werden. Mit ca. 70 % hat die Mehrheit der homöopathisch arbeitenden Pädiater in Deutschland eine positive Einstellung zum Impfen. Sie sind aber auch mehrheitlich individuelle Impfkritiker. Die stärkste Impfkritik ist unter rein klassischen Homöopathen zu finden, welche ca. 47 % der Pädiater mit Zusatzbezeichnung Homöopathie ausmachen. Die Zusatzbezeichnung Homöopathie hat von allen relevanten Variablen den größten Einfluss auf eine impfkritische Einstellung und entsprechendes Verhalten. Abweichungen von den STIKO-Empfehlungen betreffen aber überwiegend spätere Impfungen (überwiegend 1–3 Monate), sowie neuere Impfungen wie gegen Pneumokokken, Varizellen und Meningokokken. Als häufigster Grund für Abweichungen von den STIKO-Richtlinien wurde der Wunsch der Patienten angegeben. Da impfkritische Eltern eher Pädiater mit komplementärmedizinischem Zusatzangebot auswählen, beeinflussen sie auch die Erfahrungen und das Impfverhalten des Arztes. Es kann davon ausgegangen werden, dass sich das Patientenklientel von Homöopathen und Nicht-Homöopathen systematisch unterscheidet. Unterschiedliche Erfahrungen durch den Umgang mit Ungeimpften und den Möglichkeiten homöopathischer Behandlungen könnten die Veränderungen der Impfeinstellung hin zu mehr Impfkritik im Lebenslauf von Homöopathen erklären. Homöopathen geben mit Abstand am häufigsten (über 60 %) eine Veränderung in ihrer Einstellung zum Impfen im Lebenslauf an, Nicht-Homöopathen in nur ca. 10–22 %. Bezüglich der Impfentscheidung der Patienten hat wiederum die persönliche ärztliche Empfehlung als wichtigste Vertrauensperson einen großen Stellenwert. Erfahrungen und Einstellung beeinflussen sich wechselseitig. Basierend auf der Zufallsstichprobe haben ca. 10 % aller niedergelassenen Pädiater Deutschlands die Zusatzbezeichnung Homöopathie. Es gibt Hinweise, dass die Zusatzbezeichnung Homöopathie auf Grund der Patientennachfrage zugenommen hat. Das kann die häufige Anwendung von Homöopathie unter Pädiatern ohne Zusatzbezeichnung Homöopathie (ca. 40 %) erklären. Entsprechend dem marktwirtschaftlichen Prinzip des Gesundheitssystems wird die Homöopathie trotz wissenschaftlich strittiger Studienlage zunehmend von den Kassen vergütet, u.a. um konkurrenzfähig zu bleiben und Kosten vor allem im Bereich chronischer Krankheiten zu reduzieren. Ausblick: Ein Arzt sollte sich der Wirkung seiner Impf-Einstellung auf seine Patienten bewusst sein und bei seiner Impfberatung die Erwartungen und auch die Impfkritik seiner Patienten berücksichtigen. Die Komplexität und Vielseitigkeit des Impfthemas sollte den Impfentscheidern (Patienten) nicht vorenthalten werden sondern eine eigenverantwortliche Impfentscheidung (wie gesetzlich vorgesehen) fördern. Eine fundierte, neutrale und individualisierte Impf-Beratung sollte daher fester Bestandteil der medizinischen Ausbildung sein und in der Umsetzung auch entsprechend honoriert werden, unabhängig von der Impfentscheidung der Patienten. Damit können Verunsicherungen durch zT. emotionalisierende und polarisierende Informations-Medien (Internet, soziales Umfeld, Hebammen) vorgebeugt werden. Bei zunehmender Verbreitung von Komplementärmedizin und speziell der Homöopathie sollten das Thema Komplementärmedizin in der medizinischen Ausbildung fest integriert werden und entsprechend den Möglichkeiten zur Heilungsunterstützung in der Forschung und klinischen Anwendung den entsprechenden Stellenwert bekommen.

Background: Cardiovascular disease (CVD) remains the major cause of mortality and morbidity worldwide and produces large productivity loss. The majority of CVD mortality could be prevented with changes in modifiable risk factors including tobacco use, physical inactivity, unhealthy diet and harmful use of alcohol. Successful behavioral prevention of CVD requires the identification of relevant target behaviors and reach of populations at risk. Presenteeism i.e. attending work while ill is discussed as a work-related risk factor for CVD. However, little is known about the interplay of presenteeism with established health risk behaviors. The first aim of this dissertation was to examine the association of presenteeism with health behaviors (study 1). The second aim was to examine factors that can enhance the public health impact of CVD prevention efforts. Therefore, the effect of recruitment strategy used on reach (study 2) and of communication channel used on intervention usage (study 3) was examined. Methods: Study 1 comprised data from 710 Australian employees aged 18 years and older who completed an online-survey. Linear regression analysis was used to examine the association of health behaviors (physical activity, work and non-work-related sitting time, sleep duration and sleep quality) with presenteeism. For study 2 individuals aged 40-65 years were invited to a two-stage cardio-preventive program including an on-site health screening and a cardiovascular examination program (CEP) using face-to-face recruitment in general practices (n = 671) and job centers (n = 1,049), and mail invitations from a health insurance company (n = 894). Recruitment strategies were compared regarding three aspects of reach: (1) participation rate, (2) participants’ characteristics i.e. socio-demographics, self-reported health and CVD risk factors, and (3) predictors of program participation. Study 3 compromised 16,948 users (aged 18 years and older) of the feely available physical activity promotion program 10,000 Steps. Users were grouped based on which platform (website, app) they logged their physical activity: Web-only, App-only, or Web-and-app. Groups were compared on socio-demographics, engagement parameters and logged physical activity. Non-usage attrition i.e. discontinued program usage over the first three months was examined using Kaplan-Meier survival curves. A Cox regression model was used to determine predictors of non-usage attrition. Results: Analyses from study 1 revealed that presenteeism was associated with poor sleep quality and suboptimal sleep duration after controlling for socio-demographics, work and health-related variables. Engaging in three health risk behaviors was associated with higher presenteeism compared with engaging in none or one. Study 2 showed screening participation rates of 56.0%, 32.8%, 23.5% for general practices, job centers and the health insurance company, respectively. Participation rate for the CEP among eligible individuals was 80.3%, 65.5%, and 96.1%, respectively. Job center clients showed the lowest socio-economic status and the most adverse CVD risk pattern. Whereas being female predicted screening participation across all strategies, higher age predicted screening participation only within individuals recruited via the health insurance company. Within general practices and job centers CEP participants were less likely to be smokers than non-participants. Study 3 revealed that engagement with the program was highest for Web-and-app users. Cox regression showed that user group predicted non-usage attrition: Web-and-app users (hazard ratio = 0.86; P < .001) and App-only users (hazard ratio = 0.63; P < .001) showed a reduced attrition risk compared to Web-only users. Further, older age, being male, being non-Australian, higher program engagement and higher number of steps logged were associated with reduced non-usage attrition risk. Conclusion: The results of this dissertation have three implications for designing CVD behavioral interventions with a high public health impact. First, employees suffering from presenteeism may require interventions addressing health risk behaviors including suboptimal sleep behaviors. Second, implementing prevention efforts in job centers may be especially useful to reduce health inequalities induced by social gradient. Third, the population impact of web-based interventions may be increased when using mobile delivery channels.