Understanding Outstanding: quality assurance in colonoscopy

Since a couple of years, quality assurance (QA) stands at the core of the attention in the healthcare sector. Especially after the publication in 2000 of the Institute of Medicine’s report ‘To err is human’ the interest in QA has taken a quantum leap and many quality initiatives have been developed. This report revealed that every year in the United States approximately 98,000 patients died because of medical errors. Following this report, within the healthcare sector the awareness arose that the quality of the service had to improve, with special attention to safety and patient experiences. Since then the healthcare sector has learned some important lessons in QA from other industries such as the airline industry and energy sector, which are generally classified as ultra-safe organizations. Gastrointestinal endoscopy has been one of the medicine specialties which enrolled important quality initiatives. Especially since the introduction of colorectal cancer (CRC) screening programs, many efforts have been undertaken to better understand the concept of high quality endoscopy. CRC screening has been proven to decrease the incidence of CRC, and CRC related mortality. Therefore many institutions and societies recommend to screen asymptomatic individuals by fecal occult blood tests, flexible sigmoidoscopy, or colonoscopy. As these screening programs involve healthy individuals, the cost-effectiveness of such programmatic screening approaches is highly dependent on the quality of the procedure, but also on pre- and post-procedure quality aspects to improve screenee experiences and thereby the uptake of and adherence to screening modalities. In the Netherlands, CRC screening is about to start in 2013 by means of biennial fecal immunochemical testing. To attain the highest effect a comprehensive QA program should be enrolled with major focus on endoscopy as secondary screening method, as is recommended now by the European Union. The other diagnostic and therapeutic service

A Scale-out Blockchain for Value Transfer with Spontaneous Sharding

Bitcoin, as well as many of its successors, require the whole transaction record to be reliably acquired by all nodes to prevent double-spending. Recently, many blockchains have been proposed to achieve scale-out throughput by letting nodes only acquire a fraction of the whole transaction set. However, these schemes, e.g., sharding and off-chain techniques, suffer from a degradation in decentralization or the capacity of fault tolerance. In this paper, we show that the complete set of transactions is not a necessity for the prevention of double-spending if the properties of value transfers is fully explored. In other words, we show that a value-transfer ledger like Bitcoin has the potential to scale-out by its nature without sacrificing security or decentralization. Firstly, we give a formal definition for the value-transfer ledger and its distinct features from a generic database. Then, we introduce an off-chain based scheme with a shared main chain for consensus and an individual chain for each node for recording transactions. A locally executable validation scheme is proposed with uncompromising validity and consistency. A beneficial consequence of our design is that nodes will spontaneously try to reduce their transmission cost by only providing the transactions needed to show that their transactions are double-spending-proof. As a result, the network is sharded as each node only acquires part of the transaction record and a scale-out throughput could be achieved, which we call "spontaneous sharding".Comment: Accepted by Crypto Valley Conference for Blockchain Technology 201

Widespread transfer of resistance genes between bacterial species in an intensive care unit: implications for hospital epidemiology

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Privacy Architectures: Reasoning About Data Minimisation and Integrity

Privacy by design will become a legal obligation in the European Community if the Data Protection Regulation eventually gets adopted. However, taking into account privacy requirements in the design of a system is a challenging task. We propose an approach based on the specification of privacy architectures and focus on a key aspect of privacy, data minimisation, and its tension with integrity requirements. We illustrate our formal framework through a smart metering case study.Comment: appears in STM - 10th International Workshop on Security and Trust Management 8743 (2014