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Search Results: 1 - 10 of 207315 matches for " Stefan N Willich "
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Patenting of University and Non-University Public Research Organisations in Germany: Evidence from Patent Applications for Medical Research Results
Peter Tinnemann,Jonas ?zbay,Victoria A. Saint,Stefan N. Willich
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0014059
Abstract: Patents are one of the most important forms of intellectual property. They grant a time-limited exclusivity on the use of an invention allowing the recuperation of research costs. The use of patents is fiercely debated for medical innovation and especially controversial for publicly funded research, where the patent holder is an institution accountable to public interest. Despite this controversy, for the situation in Germany almost no empirical information exists. The purpose of this study is to examine the amount, types and trends of patent applications for health products submitted by German public research organisations.
Homeopathic treatment of patients with chronic sinusitis: A prospective observational study with 8 years follow-up
Claudia M Witt, Rainer Lüdtke, Stefan N Willich
BMC Ear, Nose and Throat Disorders , 2009, DOI: 10.1186/1472-6815-9-7
Abstract: Subgroup analysis including all patients with chronic sinusitis (ICD-9: 473.9; ≥12 weeks duration) of a large prospective multicentre observational study population. Consecutive patients presenting for homeopathic treatment were followed-up for 2 years, and complaint severity, health-related quality of life (QoL), and medication use were regularly recorded. We also present here patient-reported health status 8 years post initial treatment.The study included 134 adults (mean age 39.8 ± 10.4 years, 76.1% women), treated by 62 physicians. Patients had suffered from chronic sinusitis for 10.7 ± 9.8 years. Almost all patients (97.0%) had previously been treated with conventional medicine. For sinusitis, effect size (effect divided by standard deviation at baseline) of complaint severity was 1.58 (95% CI 1.77; 1.40), 2.15 (2.38; 1.92), and 2.43 (2.68; 2.18) at 3, 12, and 24 months respectively. QoL improved accordingly, with SF-36 changes in physical component score 0.27 (0.15; 0.39), 0.35 (0.19; 0.52), 0.44 (0.23; 0.65) and mental component score 0.66 (0.49; 0.84), 0.71 (0.50; 0.92), 0.65 (0.39; 0.92), 0.74 (0.49; 1.00) at these points. The effects were still present after 8 years with SF-36 physical component score 0.38 (0.10; 0.65) and mental component score 0.74 (0.49; 1.00).This observational study showed relevant improvements that persisted for 8 years in patients seeking homeopathic treatment because of sinusitis. The extent to which the observed effects are due to the life-style regulation and placebo or context effects associated with the treatment needs clarification in future explanatory studies.Chronic sinusitis is generally accepted to be a common illness incurring considerable costs, despite limited epidemiological data[1]. It is defined as an inflammation of the nasal mucosa and paranasal sinuses for at least 12 weeks which may cause nasal blockage or congestion, mucous discharge, facial pain or pressure, and/or impaired smell. Polyps, which may or may not
Regression toward the mean – a detection method for unknown population mean based on Mee and Chua's algorithm
Thomas Ostermann, Stefan N Willich, Rainer Lüdtke
BMC Medical Research Methodology , 2008, DOI: 10.1186/1471-2288-8-52
Abstract: Several statistical approaches have been developed to analyse such situations, including the algorithm of Mee and Chua which assumes a known population mean μ. We extend this approach to a situation where μ is unknown and suggest to vary it systematically over a range of reasonable values. Using differential calculus we provide formulas to estimate the range of μ where treatment effects are likely to occur when RTM is present.We successfully applied our method to three real world examples denoting situations when (a) no treatment effect can be confirmed regardless which μ is true, (b) when a treatment effect must be assumed independent from the true μ and (c) in the appraisal of results of uncontrolled studies.Our method can be used to separate the wheat from the chaff in situations, when one has to interpret the results of uncontrolled studies. In meta-analysis, health-technology reports or systematic reviews this approach may be helpful to clarify the evidence given from uncontrolled observational studies.Regression to the mean (RTM) first described by Galton [1] is a statistical phenomenon broadly discussed when it comes to measure changes in the course of time. It occurs in situations of repeated measurements when extremely large or small values are followed by measurements in the same subjects that on average are closer to the mean of the basic population. Such changes are likely to be interpreted as a real drift, although they just might be artificial coming from the fact that the sampling of values was not random but selected.RTM affects all fields of life science, when effects of an intervention have to be evaluated in an uncontrolled longitudinal setting. Medical rehabilitation programmes for example, often are evaluated for their ability to restore the patient's ability to work. Unaware of RTM effects a patient's recovery typically is interpreted as a treatment effect [2]. Other examples include the evaluation of asthma disease management programmes [3] or
Dental indications for the instrumental functional analysis in additional consideration of health-economic aspects
Tinnemann, Peter,Roll, Stephanie,Vauth, Christoph,Willich, Stefan N.
GMS Health Technology Assessment , 2010,
Abstract: Background: Besides clinical and radiological examination instrumental functional analyses are performed as diagnostic procedures for craniomandibular dysfunctions. Instrumental functional analyses cause substantial costs and shows a considerable variability between individual dentist practices. Objectives: On the basis of published scientific evidence the validity of the instrumental functional analysis for the diagnosis of craniomandibular dysfunctions compared to clinical diagnostic procedures; the difference of the various forms of the instrumental functional analysis; the existence of a dependency on additional other factors and the need for further research are determined in this report. In addition, the cost effectiveness of the instrumental functional analysis is analysed in a health-policy context, and social, legal and ethical aspects are considered. Methods: A literature search is performed in over 27 databases and by hand. Relevant companies and institutions are contacted concerning unpublished studies. The inclusion criteria for publications are (i) diagnostic studies with the indication “craniomandibular malfunction”, (ii) a comparison between clinical and instrumental functional analysis, (iii) publications since 1990, (iv) publications in English or German. The identified literature is evaluated by two scientists regarding the relevance of content and methodical quality.Results: The systematic database search resulted in 962 hits. 187 medical and economic complete publications are evaluated. Since the evaluated studies are not relevant enough to answer the medical or health economic questions no study is included. Discussion: The inconsistent terminology concerning craniomandibular dysfunctions and instrumental functional analyses results in a broad literature search in databases and an extensive search by hand. Since no relevant results concerning the validity of the instrumental functional analysis in comparison to the clinical functional analysis are found, it is impossible to make relevant statements concerning the underlying research questions. Conclusion: Studies comparing the instrumental functional analysis to the clinical functional analysis for the diagnosis of craniomandibular dysfunctions are missing. So far the instrumental functional analysis is not systematically and independently validated in comparison to the clinical functional analysis as the reference standard. It is uncertain, whether conducting an instrumental functional analysis with a clinical functional analysis for the diagnostics of craniomandibular dysfunction
What effects has the cataract surgery on the development and progression of Age-Related Macular Degeneration (AMD)?
Bockelbrink, Angelina,Rasch, Andrej,Roll, Stephanie,Willich, Stefan N.
GMS Health Technology Assessment , 2006,
Abstract: Background: The cataract (Cataracta senilis) is the most frequent eye disease of elderly people worldwide. In Germany, the cataract operation - with currently 450,000 interventions each year the most frequent operation in ophthalmology – can be seen as routine surgery. The age related macular degeneration (AMD) is a further one of the most common, age-related eye diseases and the most frequent cause of blindness of elderly people in industrial nations. Due to demographic changes an increasing number of patients will suffer from cataract and AMD at the same time. This coincidence leads to a greater interest in the question of a mutual influence of both diseases, respectively their therapies, on each other. Objectives: The aim of this report was the evaluation of the medical and health economic effects of cataract operations on the development and progression of an age related macular degeneration (AMD). It was differentiated between first manifestations of AMD, progression of early stages of AMD and influence on further impairment in late stages of AMD. Methods: The relevant publications for this report were identified by DIMDI via structured database enquiry as well as common, self-made enquiry and were evaluated, based on the criteria of evidence based medicine. The present report included German and English literature published since 1983. Results: The database enquiry generated a record of 2769 issue-related publications. Eight medical publications were eligible for analysis in the course of the present HTA report. No relevant studies on health economical, ethical, social or legal issues could be included. Three epidemiological cohort studies provided some evidence for a promoting influence of cataract extractions on the progression of early types of AMD. Two of the epidemiological studies assessed the risk of first manifestation of AMD after cataract extraction. Both came up with up with increased incidences that did not reach statistical significance despite a large number of participants. Only one out of two clinical studies looked at further impairment in late stages of AMD and could not find an interrelation with cataract extraction. Thus the available evidence was not sufficient to come to a conclusion on the contribution of cataract extractions to the first manifestation of AMD and to the further impairment in late stages. Discussion: The presentation of the evaluated literature made clear that only a small number of publications dealt with the development of age related macula degeneration in consequence of a cataract extraction. The overall
Are the Effects of Homeopathy Attributable to a Statistical Artefact? A Reanalysis of an Observational Study
Rainer Lüdtke,Stefan N. Willich,Thomas Ostermann
Evidence-Based Complementary and Alternative Medicine , 2013, DOI: 10.1155/2013/612890
Abstract: Background. Cohort studies have reported that patients improve considerably after individualised homeopathic treatment. However, these results may be biased by regression to the mean (RTM). Objective. To evaluate whether the observed changes in previous cohort studies are due to RTM and to estimate RTM adjusted effects. Methods. SF-36 quality-of-life (QoL) data from a German cohort of 2827 chronically diseased adults treated by a homeopath were reanalysed by Mee and Chua’s modified -test. Results. RTM adjusted effects, standardized by the respective standard deviation at baseline, were 0.12 (95% CI: 0.06–0.19, ) in the mental and 0.25 (0.22–0.28, ) in the physical summary score. Small-to-moderate effects were confirmed for the most individual diagnoses in physical, but not in mental component scores. Under the assumption that the true population mean equals the mean of all actually diseased patients, RTM adjusted effects were confirmed for both scores in most diagnoses. Conclusions. Changes in QoL after treatment by a homeopath are small but cannot be explained by RTM alone. As all analyses made conservative assumptions, true RTM adjusted effects are probably larger than presented. 1. Introduction Homeopathy is a whole medical system practiced in many regions of the world [1], especially in high-income countries where it ranks as the most popular among the traditional, complementary, or alternative medicines [1–3]. In homeopathy, a diagnosis can be treated with different medicines in different patients “individualization”, depending on varying concomitant symptoms. Homeopathic medicines (remedies) are produced by alternating steps of diluting and agitating a starting substance; the resulting “potencies” quickly reach dilutions beyond Avogadro’s number where the probability that one molecule of the starting substance is still present rapidly approaches zero. Such “high potencies” are often used, and their effects constitute a subject of scientific controversy [4]. Systematic reviews of placebocontrolled trials (pooling a great variety of diseases and ailments) [5–7] have shown inconsistent results. Treatment by homeopaths is typically regarded as a complex health intervention, which cannot be reduced to the efficacy of homeopathic medicines alone. It is claimed that the special style of case-taking, a different approach on how to manage conventional therapies, and specific life-style recommendations must both be considered as intrinsic parts of a homeopathic treatment. If so, randomised controlled trials on homeopathic medicines alone might be
Effects of Ginkgo biloba in dementia: systematic review and meta-analysis
Stefan Weinmann, Stephanie Roll, Christoph Schwarzbach, Christoph Vauth, Stefan N Willich
BMC Geriatrics , 2010, DOI: 10.1186/1471-2318-10-14
Abstract: We searched MEDLINE, EMBASE, the Cochrane databases, CINAHL and PsycINFO for controlled trials of ginkgo for Alzheimer's, vascular or mixed dementia. Studies had to be of a minimum of 12 weeks duration with at least ten participants per group. Clinical characteristics and outcomes were extracted. Meta-analysis results were expressed as risk ratios or standardized mean differences (SMD) in scores.Nine trials using the standardized extract EGb761? met our inclusion criteria. Trials were of 12 to 52 weeks duration and included 2372 patients in total. In the meta-analysis, the SMDs in change scores for cognition were in favor of ginkgo compared to placebo (-0.58, 95% confidence interval [CI] -1.14; -0.01, p = 0.04), but did not show a statistically significant difference from placebo for activities in daily living (ADLs) (SMD = -0.32, 95% CI -0.66; 0.03, p = 0.08). Heterogeneity among studies was high. For the Alzheimer subgroup, the SMDs for ADLs and cognition outcomes were larger than for the whole group of dementias with statistical superiority for ginkgo also for ADL outcomes (SMD = -0.44, 95% CI -0.77; -0.12, p = 0.008). Drop-out rates and side effects did not differ between ginkgo and placebo. No consistent results were available for quality of life and neuropsychiatric symptoms, possibly due to the heterogeneity of the study populations.Ginkgo biloba appears more effective than placebo. Effect sizes were moderate, while clinical relevance is, similar to other dementia drugs, difficult to determine.The standardized Ginkgo biloba extract EGb 761? is one of the most widely used herbal remedies for dementia and cognitive impairment and remains one of the best evaluated and characterized extracts [1]. Since 2000, according to the current ATC-classification, Ginkgo biloba special extract is listed in the group of anti-dementia drugs together with cholinesterase inhibitors and memantine. However, most efficacy and effectiveness studies are small, suffer from methodologi
Efficacy of Injections with Disci/Rhus Toxicodendron Compositum for Chronic Low Back Pain – A Randomized Placebo-Controlled Trial
Daniel Pach, Benno Brinkhaus, Stephanie Roll, Karl Wegscheider, Katja Icke, Stefan N. Willich, Claudia M. Witt
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0026166
Abstract: Background The effectiveness of injection therapy for low-back pain is still debatable. We compared the efficacy of local injections of the homeopathic preparation Disci/Rhus toxicodendron compositum (verum) with placebo injections and with no treatment in patients with chronic low back pain. Methodology/Principal Findings In a randomized controlled partly double blind multicenter trial patients with chronic low back pain from 9 German outpatient clinics were enrolled and randomly allocated in a 1:1:1 ratio to receive subcutaneous injections (verum or placebo) into painful sites on the lower back over 12 treatment sessions within eight weeks, or no treatment (rescue pain medication with paracetamol or NSAIDs). All trial personnel and participants were masked to treatment allocation. The primary outcome measure was the average pain intensity over the last seven days on a visual analogue scale (0–100 mm, 0 = no pain, 100 = worst imaginable pain) after eight weeks. Follow-up was 26 weeks. Primary analysis was by intention to treat. Between August 2007 and June 2008, 150 patients were randomly allocated to three groups (51 verum, 48 placebo and 51 no treatment). The mean baseline-adjusted low back pain intensity at week eight was: verum group 37.0 mm (97.5% CI 25.3;48.8), no treatment group 53.0 (41.8;64.2), and placebo group 41.8 (30.1;53.6). The verum was significantly superior to no treatment (P = 0.001), but not to placebo (P = 0.350). No significant side effects were reported. Conclusions/Significance The homeopathic preparation was not superior to placebo. Compared to no treatment injections resulted in significant and clinical relevant chronic back pain relief. Trial Registration ClinicalTrials.gov NCT00567736
Promotion of Physical Activity Using Point-of-Decision Prompts in Berlin Underground Stations
Falk Müller-Riemenschneider,Marc Nocon,Thomas Reinhold,Stefan N. Willich
International Journal of Environmental Research and Public Health , 2010, DOI: 10.3390/ijerph7083063
Abstract: To evaluate point-of-decision prompts in the promotion of stair use in Germany, motivational posters were placed at three underground stations in Berlin. The proportion of passengers using stairs or stairways was counted before, during installation, and two weeks after removal of posters. In total, 5,467 passersby were counted. Stair use increased significantly in women, but not in men. The present pilot study thereby shows that the use of point-of-decision prompts is also feasible in Germany and it provides some evidence of effectiveness. Methodologically rigorous studies are warranted to confirm these findings.
Educational intervention to improve physician reporting of adverse drug reactions (ADRs) in a primary care setting in complementary and alternative medicine
Manuela Tabali, Elke Jeschke, Angelina Bockelbrink, Claudia M Witt, Stefan N Willich, Thomas Ostermann, Harald Matthes
BMC Public Health , 2009, DOI: 10.1186/1471-2458-9-274
Abstract: Objective was to evaluate the impact of an educational intervention and monitoring programme designed to improve physician reporting of ADRs in a primary care setting.A prospective multicentre study with 38 primary care practitioners specialized in CAM was conducted from January 2004 through June 2007. After 21 month all physicians received an educational intervention in terms of face-to-face training to assist them in classifying and reporting ADRs. The study centre monitored the quantity and quality of ADR reports and analysed the results.To measure changes in the ADR reporting rate, the median number of ADR reports and interquartile range (IQR) were calculated before and after the educational intervention. The pre-intervention and post-intervention quality of the reports was assessed in terms of changes in the completeness of data provided for obligatory items. Interrater reliability between the physicians and the study centre was calculated using Cohen's kappa with a 95% confidence interval (CI). We used Mann Whitney U-test for testing continuous data and chi-square test was used for categorical data. The level of statistical significance was set at P < 0.05.A total of 404 ADRs were reported during the complete study period. An initial 148% increase (P = 0.001) in the number of ADR reports was observed after the educational intervention. Compared to baseline the postinterventional number of ADR reportings was statistically significant higher (P < 0.005) through the first 16 months after the intervention but not significant in the last 4-month period (median: 8.00 (IQR [2.75; 8.75]; P = 0.605). The completeness of the ADR reports increased from 80.3% before to 90.7% after the intervention. The completeness of the item for classifying ADRs as serious or non-serious increased significantly (P < 0.001) after the educational intervention. The quality of ADR reports increased from kappa 0.15 (95% CI: 0.08; 0.29) before to 0.43 (95% CI: 0.23; 0.63) after the interventi
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