Introduction: Many recent studies have investigated the hospital volume-outcome relationship in surgery. In some cases, the results have prompted the centralization of surgical activity. However, the methodologies and interpretations differ markedly from one study to another. The objective of the present scoping review was to describe the various features used to assess the volume-outcome relationship: the analyzed datasets, study population, outcome, covariates, confounders, volume modalities, and statistical methods. Methods and analysis: The review was conducted according to a study protocol published in BMJ Open in 2020. Two authors (both of whom had helped to design the study protocol) screened publications independently according to the title, the abstract and then the full text. To ensure exhaustivity, all the papers included by each reviewer went through to the next step. Interpretation: The 403 included studies covered 90 types of surgery, 61 types of outcome, and 72 covariates or potential confounders. 191 (47.5%) studies focussed on oncological surgery and 37.8% focussed visceral or digestive tract surgery. Overall, 86.6% of the studies found a statistically significant volume-outcome relationship, although the findings differed from one type of surgery to another. Furthermore, the types of outcome and the covariates were highly diverse. The majority of studies were performed in Western countries, and oncological and visceral surgical procedures were over-represented; this might limit the generalizability and comparability of the studies’ results.

Usability flaws in medication alerting systems may have a negative impact on clinical use and patient safety. In order to prevent the release of alerting systems that contain such flaws, it is necessary to provide designers and evaluators with evidence-based usability design principles. The objective of the present study was to develop a comprehensive, structured list of evidence-based usability design principles for medication alerting systems. Nine sets of design principles for medication alerting systems were analyzed, summarized, and structured. We then matched the summarized principles with a list of usability flaws in order to determine the level of underlying evidence. Fifty-eight principles were summarized from the literature and two additional principles were defined, so that each flaw was matched with a principle. We organized the 60 summarized usability design principles into 6 meta-principles, 38 principles, and 16 sub-principles. Only 15 principles were not matched with a usability flaw. The 6 meta-principles respectively covered the improvement of the signal-to-noise ratio, the support for collaborative working, the fit with a clinician’s workflow, the data display, the transparency of the alerting system, and the actionable tools to be provided within an alert. It is possible to develop an evidence-based, structured, comprehensive list of usability design principles that are specific to medication alerting systems and are illustrated by the corresponding usability flaws. This list represents an improvement over the current literature. Each principle is now associated with the best available evidence of its violation. This knowledge may help to improve the usability of medication alerting systems and, ultimately, decrease the harmful consequences of the systems’ usability flaws.

A large proportion of the patient injuries or deaths attributable to medical device (MD) misuse can be eliminated and/or mitigated by adopting an effective human factors and ergonomics (HFE) approach. The implementation of a usability engineering process is now mandatory for MD manufacturers seeking to obtain the European Union’s CE Mark. Here, we describe the European Union’s HFE regulation and highlight the challenges faced by (i) manufacturers implementing this regulation and (ii) regulatory bodies charged with assessing the compliance of usability files. In Europe, 95% of MD manufacturers are small- and medium-sized enterprises; compliance with the CE Mark regulations is a real challenge to their competitiveness. Levels of knowledge about HFE vary greatly from one regulatory organization to another, which can sometimes lead to very different expectations. We also present the specific use-related risk management approach required by the HFE regulation. Lastly, we focus on the limitations of the HFE regulation for MDs and on future HFE challenges in further reducing and/or eliminating MD use errors. The main challenge is the need to go beyond technology design and the premarket assessment and to look at the postproduction stage; the coupling between an MD and a sociotechnical system can lead to consequences that were not predicted during the design process. This implies the need to consider the emerging properties of technologies in use by involving all the stakeholders.