The influence of candidates' physical attributes on patient ratings in simulated assessments of clinical practice.

BACKGROUND: We have previously shown that clinical examiners' scoring is not negatively impacted when a candidate has a tattoo, unnatural hair colour, or a regional accent. We investigated whether these physical attributes in exam candidates impact patient scoring. METHODS: Simulated/real patients were randomly assigned to watch five videos of simulated candidate performances of a cranial nerve examination: clear fail, borderline, good, 'clear pass' without an attribute, and 'clear pass' with one of the attributes (tattoo, purple hair, accent). Participants scored domains of communication and professionalism. We compared scores for the clear pass candidates with and without attributes. RESULTS: One hundred and eighty three patients participated. The total scores for the candidates with tattoos and purple hair were higher than the candidate with no physical attribute (p < 0.001). For the candidate with a Liverpool English accent no difference was identified (p = 0.120). CONCLUSIONS: The presence of certain physical attributes (tattoos or purple hair) was associated with higher scores given by patients to candidates in a simulated physical examination station.

The influence of candidates' physical attributes on assessors' ratings in clinical practice.

BACKGROUND: Assessments of physician competence in the work-place are common and often contribute to high-stakes assessments. Previous research suggests that assessors' judgements can be influenced by candidates' physical attributes. We investigated whether simulated candidates' scores were influenced by assessor bias based on tattoos, hair colour, and a regional accent. METHODS: We used an experimental, video-based, single-blinded, randomised, internet-based design. We created videos of simulated medical intern performances of a clinical examination at four different standards of competence. Four videos were also created of simulated candidates performing at a 'clear pass' standard, with either no stereotypical attribute (CPX), purple hair (CPH), tattoos (CPT) or a Liverpool English accent (CPA). Assessors were randomly assigned to watch five videos including the "clear pass" candidate without an attribute and one of the "clear pass" candidates with an attribute and asked to give an overall global grade for each candidate. We compared the global grades for the clear pass candidates with and without attributes. RESULTS: Ninety-eight assessors were included in the analysis. The total scores for the candidates with stereotyped attributes were not significantly lower than the candidate with no attribute. Assessors showed moderate levels of agreement between the global grades awarded for all the candidates. The global grades awarded to candidate with a stereotypical attribute were not significantly lower than for those without. CONCLUSIONS: The presence of tattoos, purple hair, or a regional accent did not systematically negatively influence the grade or score awarded by assessors to candidates in observed clinical examination scenarios.

Quantifying the Mesoscopic Nature of Einstein-Podolsky-Rosen Nonlocality.

Evidence for Bell's nonlocality is so far mainly restricted to microscopic systems, where the elements of reality that are negated predetermine results of measurements to within one spin unit. Any observed nonlocal effect (or lack of classical predetermination) is then limited to no more than the difference of a single photon or electron being detected or not (at a given detector). In this paper, we analyze experiments that report the Einstein-Podolsky-Rosen (EPR) steering form of nonlocality for mesoscopic photonic or Bose-Einstein condensate systems. Using an EPR steering parameter, we show how the EPR nonlocalities involved can be quantified for four-mode states, to give evidence of EPR-nonlocal effects corresponding to a two-mode number difference of 10^{5} photons, or of several tens of atoms (at a given site). Applying to experiments, we also show how the variance criterion of Duan, Giedke, Cirac and Zoller for EPR entanglement can be used to determine a lower bound on the number of particles in a pure two-mode EPR-entangled or steerable state.

Pulsed Entanglement of Two Optomechanical Oscillators and Furry's Hypothesis.

A strategy for generating entanglement between two separated optomechanical oscillators is analyzed, using entangled radiation produced from down-conversion and stored in an initiating cavity. We show that the use of pulsed entanglement with optimally shaped temporal modes can efficiently transfer quantum entanglement into a mechanical mode, then remove it after a fixed waiting time for measurement. This protocol could provide new avenues for testing for bounds on decoherence in massive systems that are spatially separated, as originally suggested by Furry not long after the discussion by Einstein-Podolsky-Rosen and Schrödinger of entanglement.

Nonlinear entanglement and its application to generating cat States.

The Einstein-Podolsky-Rosen (EPR) paradox, which was formulated to argue for the incompleteness of quantum mechanics, has since metamorphosed into a resource for quantum information. The EPR entanglement describes the strength of linear correlations between two objects in terms of a pair of conjugate observables in relation to the Heisenberg uncertainty limit. We propose that entanglement can be extended to include nonlinear correlations. We examine two driven harmonic oscillators that are coupled via third-order nonlinearity can exhibit quadraticlike nonlinear entanglement which, after a projective measurement on one of the oscillators, collapses the other into a cat state of tunable size.

Classifying directional Gaussian entanglement, Einstein-Podolsky-Rosen steering, and discord.

Using Venn diagrams, we classify the different types of two-mode Gaussian continuous variable quantum correlation including directional entanglement and Einstein-Podolsky-Rosen (EPR) steering. We establish unified signatures for one- and two-way quantum steering, entanglement, and discord beyond entanglement in terms of an EPR-type variance. By focusing on Gaussian states, we link an optimized condition for entanglement based on an EPR variance to the Simon-Peres condition. This allows us to quantify the asymmetry of the Gaussian entanglement, and to relate the asymmetry to a directional quantum teleportation protocol where Alice and Bob possess asymmetrically noisy channels. Our analysis enables a determination of the type and direction of quantum correlation in a way that is easily measured in experiment. We also find that for symmetric states, when discord exceeds a certain threshold, the states are necessarily steerable.

Genuine multipartite Einstein-Podolsky-Rosen steering.

We develop the concept of genuine N-partite Einstein-Podolsky-Rosen (EPR) steering. This nonlocality is the natural multipartite extension of the original EPR paradox. Useful properties emerge that are not guaranteed for genuine multipartite entangled states. In particular, there is a close link with the task of one-sided, device-independent quantum secret sharing. We derive inequalities to demonstrate multipartite EPR steering for Greenberger-Horne-Zeilinger and Gaussian continuous variable states in loophole-free scenarios.

Einstein-Podolsky-Rosen entanglement strategies in two-well Bose-Einstein condensates.

Criteria suitable for measuring entanglement between two different potential wells in a Bose-Einstein condensation are evaluated. We show how to generate the required entanglement, utilizing either an adiabatic two-mode or a dynamic four-mode interaction strategy, with techniques that take advantage of s-wave scattering interactions to provide the nonlinear coupling. The dynamic entanglement method results in an entanglement signature with spatially separated detectors, as in the Einstein-Podolsky-Rosen paradox.

Testing for multipartite quantum nonlocality using functional bell inequalities.

We show that arbitrary functions of continuous variables, e.g., position and momentum, can be used to generate tests that distinguish quantum theory from local hidden variable theories. By optimizing these functions, we obtain more robust violations of local causality than obtained previously. We analytically calculate the optimal function and include the effect of nonideal detectors and noise, revealing that optimized functional inequalities are resistant to standard forms of decoherence. These inequalities could allow a loophole-free Bell test with efficient homodyne detection.

Digital quantum memories with symmetric pulses.

We propose a digital approach to quantum memories using a single-mode oscillator-cavity model, in which the coupling is shaped in time to provide the optimum interface to a time-symmetric input pulse. Our generic model is applicable to any linear storage medium ranging from a superconducting device to an atomic medium.