Experimental evidence of delocalized states in random dimer superlattices

We study the electronic properties of GaAs-AlGaAs superlattices with intentional correlated disorder by means of photoluminescence and vertical dc resistance. The results are compared to those obtained in ordered and uncorrelated disordered superlattices. We report the first experimental evidence that spatial correlations inhibit localization of states in disordered low-dimensional systems, as our previous theoretical calculations suggested, in contrast to the earlier belief that all eigenstates are localized.Comment: 4 pages, 5 figures. Physical Review Letters (in press

Cost-effectiveness of timely versus delayed primary total hip replacement in Germany: A social health insurance perspective

Without clinical guideline on the optimal timing for primary total hip replacement (THR), patients often receive the operation with delay. Delaying THR may negatively affect long-term health-related quality of life, but its economic effects are unclear. We evaluated the costs and health benefits of timely primary THR for functionally independent adult patients with end-stage osteoarthritis (OA) compared to non-surgical therapy followed by THR after progression to functional dependence (delayed THR), and non-surgical therapy alone (Medical Therapy), from a German Social Health Insurance (SHI) perspective. Data from hip arthroplasty registers and a systematic review of the published literature were used to populate a tunnel-state modified Markov lifetime model of OA treatment in Germany. A 5% annual discount rate was applied to costs (2013 prices) and health outcomes (Quality Adjusted Life Years, QALY). The expected future average cost of timely THR, delayed THR and medical therapy in women at age 55 were €27,474, €27,083 and €28,263, and QALYs were 20.7, 16.7, and 10.3, respectively. QALY differences were entirely due to health-related quality of life differences. The discounted cost per QALY gained by timely over delayed (median delay of 11 years) THR was €1270 and €1338 in women treated at age 55 and age 65, respectively, and slightly higher than this for men. Timely THR is cost-effective, generating large quality of life benefits for patients at low additional cost to the SHI. With declining healthcare budgets, research is needed to identify the characteristics of those able to benefit the most from timely THR

A Probiotic-Based Sanitation System for the Reduction of Healthcare Associated Infections and Antimicrobial Resistances: A Budget Impact Analysis

Healthcare Associated Infections (HAIs) and antibiotic resistance have high social and economic burdens. Healthcare environments play an important role in the transmission of HAIs. The Probiotic Cleaning Hygiene System (PCHS) showed to decrease hospital surface pathogens up to 90% vs. conventional chemical cleaning (CCC). This study compares PCHS to CCC as to reduction of HAIs and their severity, related antibiotic resistances, and costs. Incidence rates of HAIs/antibiotic resistances were estimated from a multicenter pre-post (6 months CCC + 6 months PCHS) intervention study after applying propensity score matching technique. A budget impact analysis compared the current scenario of use of CCC with future scenarios considering increasing utilization of PCHS, from 5% to 50% in the next five years, from the hospital perspective in Italy. The cumulative incidence of HAI was 4.6% and 2.4% (p <0.0001) for CCC (N=4,160) and PCHS (N=4,160) (OR = 0.47, CI 95% 0.37-0.60), with severe HAIs of 1.57% vs 1% and antibiotic resistances of 1.13% vs 0.53%, respectively. Increased use of PCHS over CCC in Italian internal medicine/geriatrics and neurology departments in the next 5 years is expected to avert at least about 31,000 HAIs and 8,500 antibiotic resistances, and save at least 14 million Euros, of which 11.6 for the treatment of resistant HAIs. Innovative, environmentally sustainable sanitation systems, like PCHS, might substantially reduce antibiotic resistance and increase protection of health worldwide

Psychometric evaluation of the German version of a social support scale of FAFHES (family functioning, family health and social support)

This is the peer reviewed version which has been published in final form at https://doi.org/10.1111/scs.12700. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.BACKGROUND: Family members often need to be supported in informal care of the elderly and desire to be involved into care planning and decision-making. Valid and reliable instruments are needed to measure how family members perceive the care and support they receive from nurses for older family members living at home. AIM: The purpose of this study was to translate the 20-item social support scale of the Family Functioning, Family Health and Social Support (FAFHES) questionnaire from English to German and test the validity and reliability of the scale among Swiss-German-speaking family caregivers of home-dwelling elderly people who receive home healthcare services. METHODS: A cross-sectional study was conducted to test the empirical and psychometric properties of the translated and culturally adapted version of the social support questionnaire. A factor analysis with the principal component analysis PCA was used to test construct validity. The internal consistency of items was measured with the Cronbach`s alpha coefficient. RESULTS: After a rigorous translation process the original 20-item questionnaire was adapted into a 19-item version and tested with family caregivers (n = 207) of home-dwelling elderly. Psychometric testing of the German version of the social support questionnaire revealed that the three factors - affirmation, affect and concrete aid - were congruent with the original questionnaire. The accounted variance was 79.5% and the internal consistency determined by the Cronbach's alpha was 0.973. CONCLUSION: The German version of the social support scale of the FAFHES questionnaire is a valid and reliable instrument to assess family perceived support on three dimensions - affirmation, affect and concrete aid - received from nursing professionals. The questionnaire should be tested further in other German-speaking population

When a probiotic-based sanitizing method may halve healthcare-associated infections and reduce associated costs

No abstract availabl

Incentivizing research into the effectiveness of medical devices

Introduction Medical devices (MDs) often obtain market authorization with much less clinical evidence than other health technologies, especially pharmaceuticals. This is due to a number of reasons. First, in contrast to pharmaceuticals, there is no legal requirement to conduct adequately controlled clinical studies, other than for ‘high-risk’ devices in some jurisdictions. In the US for example, high-risk devices and innovative lower-risk devices are required to demonstrate ‘reasonable assurance of safety and effectiveness’, which may imply clinical evidence based on randomized studies in many instances. In contrast, in the EU the requirement is to demonstrate adequate performance and safety, which can often be achieved by conducting observational studies such as registries [1, 2]. Secondly, the devices industry comprises many small and medium-size enterprises (SMEs), which would find the cost of conducting clinical studies, especially randomized controlled trials, prohibitive. However, although some larger manufacturers do undertake clinical studies of some of their products, manufacturers with similar products (called ‘fast-followers’) can often claim ‘substantial equivalence’ to a product that already has market authorization, thus avoiding the need to conduct costly and timeconsuming clinical studies. Since regulatory agencies often accept these claims of equivalence, for example under the 510(k) process in the US [3], this further reduces the incentives for manufacturers to conduct expensive clinical studies. Therefore, although device manufacturers have patent protection, they are often not granted data exclusivity in the same way as pharmaceutical manufacturers. Finally, unlike pharmaceuticals, devices are often modified once on the market, meaning that even if clinical evidence was available for the original version of the product, it may not necessarily be available for the version currently being marketed. For example in the US, one analysis showed that for 77 original market authorization applications for cardiac implantable electronic devices (e.g., pacemakers, implantable cardioverter-defibrillators) since 1979, the FDA approved 5829 ‘supplements’ reflecting product modifications in the period up until 2012. Of course, many of these product modifications were minor and unlikely to affect the performance of the device, but 37 % involved a change to the device’s design. In the vast majority of these cases the FDA deemed that new clinical data were not necessary for approval [4]. The lack of clinical evidence prior to product launch, especially evidence of comparative effectiveness, limits the possibilities for health technology assessment [2]. However, it should be remembered that clinical evidence can be gathered both pre-market (i.e., through conducting controlled clinical trials in an experimental setting), and postmarket, through clinical studies undertaken in regular clinical practice. Post-market effectiveness research may be more important for MDs than pharmaceuticals, as the performance of the device often depends on the interaction with the user (the so-called learning curve) [5]. This suggests that solutions to the problem of inadequate clinical evidence should address the issue of conducting clinical research in both the pre- and post-market phase. In this editorial we consider ways in which MD manufacturers could be incentivized to produce more clinical evidence to facilitate health technology assessments, including economic evaluations

Should Health Technology Assessment be more patient-centric? If so, how?

Health technology assessment (HTA) methods and processes have been criticized for not being sufficiently ‘patient centric’. For example, Perfetto [1] argued that a proposed approach for assessing the value of health care interventions had not sufficiently incorporated a patient perspective and suggested that it represented a ‘missed opportunity’. A similar point was made about the other ‘value assessment frameworks’ developed recently in the United States [2]. In addition, Slejko et al. [3] proposed some key elements of a ‘patient informed’ reference case for conducting economic evaluations, which would supplement reference cases outlined by groups such as the second Panel on Cost-Effectiveness in Health and Medicine [4], by including consideration of elements such as convenience in receiving care, effects on the patient’s family, examination of whether quality of life instruments include the most relevant domains and a model structure for the economic evaluation that adequately reflects the patient’s journey through the various treatment options. While the case to consider the patient perspective is strong, the way in which it should be incorporated in HTA is not obvious. Most HTA analysts would argue that HTAs, with the possible exception of some that are undertaken to support the development of clinical guidelines, or initiatives such as shared (clinical) decision-making, are conducted for those making decisions about the allocation of health care resources for a given population. This population may be the enrollees of a given health plan or, in the case of national health services or national insurance schemes, the whole population of a given country. The population would include patients who currently have the disease of interest, their families, those who have been patients in the past and those who may contract the disease in the future, as well as those past, present and future sufferers of other diseases. Of course, there may be considerable similarity between the perspective of patients currently suffering from a disease and the population at large, but this is not necessarily the case [5, 6, 7]. Therefore, making HTA more patient centric may not be as simple as it appears. The case for considering the patient perspective may differ by type of health care system [8]. For example, in a private insurance-based system, where a substantial proportion of the payments may be made directly by the patients, one might expect more consideration of the patient perspective than in a publicly funded national health service. The empirical evidence generated in the recent years shows that there is greater awareness about the importance of patients’ views in HTA, but there is no common understanding of what “patient-centric HTA” actually means [9]. Here, we attempt to shed further light on the issue by conceptualizing “patient centricity” in two ways: (a) encouraging patients’ engagement in HTA process and (b) enlarging the scope of evidence in HTA to include patients’ outcomes and preferences (HTA methods). We discuss the opportunities and challenges of each, by providing some recent examples from different countries. Finally, we discuss some additional ways to make HTA more patient centric

Trans-arterial radioembolization in intermediate-advanced hepatocellular carcinoma: systematic review and meta-analyses.

Published onlineJournal ArticleThis is the final version of the article. Available from Impact Journals via the DOI in this record.Trans-arterial radioembolization (TARE) is a recognized, although not explicitly recommended, experimental therapy for unresectable hepatocellular carcinoma (HCC).A systematic literature review was performed to identify published studies on the use of TARE in intermediate and advanced stages HCC exploring the efficacy and safety of this innovative treatment.Twenty-one studies reporting data on overall survival (OS) and time to progression (TTP), were included in a meta-analysis. The pooled post-TARE OS was 63% (95% CI: 56-70%) and 27% (95% CI: 21-33%) at 1- and 3-years respectively in intermediate stage HCC, whereas OS was 37% (95% CI: 26-50%) and 13% (95% CI: 9-18%) at the same time intervals in patients with sufficient liver function (Child-Pugh A-B7) but with an advanced HCC because of the presence of portal vein thrombosis. When an intermediate and advanced case-mix was considered, OS was 58% (95% CI: 48-67%) and 17% (95% CI: 12-23%) at 1- and 3-years respectively. As for TTP, only four studies reported data: the observed progression probability was 56% (95% CI: 41-70%) and 73% (95% CI: 56-87%) at 1 and 2 years respectively. The safety analysis, focused on the risk of liver decompensation after TARE, revealed a great variability, from 0-1% to more than 36% events, influenced by the number of procedures, patient Child-Pugh stage and treatment duration.Evidence supporting the use of radioembolization in HCC is mainly based on retrospective and prospective cohort studies. Based on this evidence, until the results of the ongoing randomized trials become available, radioembolization appears to be a viable treatment option for intermediate-advanced stage HCC.The present study was funded by ASBM Srl through an unrestricted grant to CERGAS, Bocconi University, Via Roentgen 1, 20136 Milan, Italy

[Myositis specific and myositis associated autoantibodies in idiopathic inflammatory myopathies: a serologic study of 46 patients]

Objective. To characterize serum autoantibody profiles of patients with idiopathic inflammatory myopathies (IIM) by searching for myositis-specific (MSA) and myositis-associated (MAA) antibodies with sensitive and specific laboratory tests. Methods. We tested the sera from 46 Caucasian patients diagnosed as affected with IIM at the Division of Rheumatology of Padova University (21 polimyositis, PM; 22 dermatomyositis, DM; 3 myositis overlap syndrome). All patients had definite IIM according to the criteria of Bohan-Peter. MSA including anti-tRNA synthetase (anti-Jo-1 and others) and anti-Mi-2 were determined by RNA immunoprecipitation and a modified immunoblot test, respectively. MAA (-U1RNP, -U2RNP, RoRNP, PM/Scl, Ku) were detected by counterimmunoelectrophoresis and immunoblot. Results. Serum MSA and/or MAA were found in 30/46 (65%) patients with IIM. Twenty-three patients (50%) were positive for at least one MSA: anti-Jo-1 in 15 (33%), anti-Mi-2 in 6 (13%), and other anti-tRNA synthetase in 3 (6%).One patient was anti-Jo-1/Mi-2 positive. Moreover, 18 patients (39%) were positive for at least one MAA: anti-Ro/SSA in 13 (28%), anti-U1RNP in 4 (9%), anti-PM/Scl in 1 (2%) and anti-Ku in 1 (2%). Coexisting MSA and MAA were observed in 8 patients (17%), anti-Jo-1/SSA positive in most cases. Anti-Jo-1 was predominantly associated with PM (57% in PM vs 14% in DM), whereas anti-Mi-2 was exclusively found in DM patients (27%). Anti-synthetase antibodies were closely associated with interstitial lung disease and polyarthritis; anti-Mi-2 positive DM patients did not have lung involvement. Notably, anti-Ro/SSA antibody was frequently observed and almost equally detected in either PM or DM (about 30%): in more than 50% of cases the antibody was associated with one MSA. Conclusions. By means of analytically reliable methods, MSA was detected in 50% of our IIM patients. Searching for MSA in patients with IIM is recommended because of its diagnostic and prognostic value