Maintaining credibility when communicating uncertainty: The role of communication format

Research into risk communication has commonly highlighted the disparity between the meaning intended by the communicator and what is understood by the recipient. Such miscommunications will have implications for perceived trust and expertise of the communicator, but it is not known whether this differs according to the communication format. We examined the effect of using verbal, numerical and mixed communication formats on perceptions of credibility and correctness, as well as whether they influenced a decision to evacuate, both before and after an ‘erroneous’ prediction (i.e. an ‘unlikely’ event occurs, or a ‘likely’ event does not occur). We observed no effect of communication format on any of the measures pre-outcome, but found the numerical format was perceived as less incorrect, as well as more credible than the other formats after an ‘erroneous’ prediction, but only when low probability expressions were used. Our findings suggest numbers should be used in consequential risk communications

A preferential loss of GABAergic, symmetric synapses in epileptic foci: a quantitative ultrastructural analysis of monkey neocortex.

Previous immunocytochemical results from five monkeys with cortical focal epilepsy produced by alumina gel showed a severe decrease at seizure foci of axon terminals that contained glutamic acid decarboxylase (GAD), the synthesizing enzyme for the inhibitory neurotransmitter, GABA. These data indicated a functional loss of GABAergic terminals but did not show: whether this loss was caused by GABAergic nerve terminal degeneration or by a lack of GAD immunoreactivity within these terminals and if this loss of GABAergic terminals was selective for only this terminal type. To resolve these issues, cortical tissue from three of the five monkeys used in the previous study was reexamined using electron microscopy, and a quantitative morphological analysis of cortical structures was made to compare profiles of terminals and glia in the nonepileptic cortex with those in the focus and parafocus. The following statistically significant changes were observed: the number of axosomatic symmetric synapses with layer V pyramidal cells was decreased 80% at the focus and 50% at the parafocus; in the neuropil adjacent to these pyramidal somata, the number of terminals forming symmetric synapses was reduced 50% at the epileptic focus but was unchanged at the parafocus, while the number of asymmetric synapses was reduced 25% at the focus and 15% at the parafocus; and a 50% increase of glial profiles occurred at epileptic foci both in the neuropil and at sites apposed to pyramidal cell somata. The quantitative results also showed that terminals which form symmetric synapses had twice the number of mitochondria per terminal as those that form asymmetric synapses. Axon terminals which form symmetric synapses with somata and dendrites in the neocortex have been shown previously to contain GAD. Therefore, the large reduction in the number of symmetric synapses at epileptic foci and the increased gliosis indicate that the previously observed loss of GABAergic terminals at sites of focal epilepsy is caused by terminal degeneration. Since such terminals are reduced more severely at epileptic foci than other terminals, their loss could be the basis for seizure activity due to a preferential decrease of inhibitory function at epileptic foci. Hypoxia has been shown to cause a selective degeneration of terminals with the same morphology as GABAergic terminals in the cortex, and the basis for this loss could be related to higher physiological and/or metabolic activities of GABAergic cortical cells which may inhibit other cells tonically. The fact that increased numbers of mitochondria occur in GABAergic terminals supports this idea

'Unlikely' outcomes might never occur, but what about 'unlikely (20% chance)' outcomes?

A commonly suggested solution to reduce misinterpretations of verbal probability expressions in risk communications is to use a verbal-numerical (mixed format) approach, but it is not known whether this increases understanding over and above a purely numerical format. Using the ‘which outcome’ methodology (Teigen & Filkuková, 2013), we examined the effect of using verbal, numerical and mixed communication formats, as well as investigating whether marking outcomes as salient would alter the outcomes people perceived as ‘unlikely’ or having a 20% chance of occurring. We observed no effect of saliency, but replicated previous findings, with general preference for values at the high end of a distribution (including maximum/above maximum values) present in both verbal and mixed communication formats. This demonstrates the relevance of these findings for real-world consequential risk communication. Whilst the estimates differed between the mixed and numerical formats, we fo

Understanding ‘Unlikely (20% Likelihood)’ or ‘20% Likelihood (Unlikely)’ Outcomes: The Robustness of the Extremity Effect

Calls to communicate uncertainty using mixed, verbal‐numerical formats (‘unlikely [0–33%]’) have stemmed from research comparing mixed with solely verbal communications. Research using the new ‘which outcome’ approach to investigate understanding of verbal probability expressions suggests, however, that mixed formats might convey disadvantages compared with purely numerical communications. When asked to indicate an outcome that is ‘unlikely’, participants have been shown to often indicate outcomes with a value exceeding the maximum value shown, equivalent to a 0% probability —an ‘extremity effect’. Recognising the potential consequences of communication recipients expecting an ‘unlikely’ event to never occur, we extend the ‘which outcome’ work across four experiments, using verbal, numerical, and verbal‐numerical communication formats, as well as a previously unconsidered numerical‐verbal format. We examine how robust the effect is in the context of consequential outcomes and over non‐normal distributions. We also investigate whether participants are aware of the inconsistency in their responses from a traditional ‘how likely’ and ‘which outcome’ task. We replicate and extend previous findings, with preference for extreme outcomes (including above maximum values) observed in both verbal and verbal‐numerical formats. Our results suggest caution in blanket usage of recently recommended verbal‐numerical formats for the communication of uncertainty

Association between glucocorticoid therapy and incidence of diabetes mellitus in polymyalgia rheumatica and giant cell arteritis: a systematic review and meta-analysis

Background: Polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) are almost always treated with glucocorticoids (GCs), but long-term GC use is associated with diabetes mellitus (DM). The absolute incidence of this complication in this patient group remains unclear. Objective: To quantify the absolute risk of GC-induced DM in PMR and GCA from published literature. Methods: We identified literature from inception to February 2017 reporting diabetes following exposure to oral GC in patients with PMR and/or GCA without pre-existing diabetes. A random-effects meta-analysis was performed to summarise the findings. Results: 25 eligible publications were identified. In studies of patients with GCA, mean cumulative GC dose was almost 1.5 times higher than in studies of PMR (8.2 g vs 5.6 g), with slightly longer treatment duration and longer duration of follow-up (6.4 years vs 4.4 years). The incidence proportion (cumulative incidence) of patients who developed new-onset DM was 6% (95% CI 3% to 9%) for PMR and 13% (95% CI 9% to 17%) for GCA. Based on UK data on incidence rate of DM in the general population, the expected background incidence rate of DM over 4.4 years in patients with PMR and 6.4 years in patients with GCA (follow-up duration) would be 4.8% and 7.0%, respectively. Heterogeneity between studies was high (I2=79.1%), as there were differences in study designs, patient population, geographical locations and treatment. Little information on predictors of DM was found. Conclusion: Our meta-analysis produced plausible estimates of DM incidence in patients with PMR and GCA, but there is insufficient published data to allow precise quantification of DM risk

Fingermark submission decision-making within a UK fingerprint laboratory: Do experts get the marks that they need?

Within UK policing it is routinely the responsibility of fingerprint laboratory practitioners to chemically develop areas of latent fingerprint ridge detail on evidential items and to determine which areas of ridge detail are of sufficient quality to be submitted to fingerprint experts for search or comparison against persons of interest. This study assessed the effectiveness of the fingermark submission process within the Evidence Recovery Unit Fingerprint Laboratory of the Metropolitan Police Service. Laboratory practitioners were presented with known source fingermark images previously deemed identifiable or insufficient by fingerprint experts, and were asked to state which of the marks they would forward to the Fingerprint Bureau. The results indicated that practitioners forwarded a higher percentage of insufficient fingermarks than is acceptable according to current laboratory guidelines, and discarded a number of marks that were of sufficient quality for analysis. Practitioners forwarded more insufficient fingermarks when considering fingermarks thought to be related to a murder and discarded more sufficient fingermarks when considering those thought to be related to a crime of 'theft from vehicle'. The results highlight the need for fingerprint laboratories to work alongside fingerprint experts to ensure that a consistent approach to decision-making is, as far as possible, achieved, and that appropriate thresholds are adopted so as to prevent the loss of valuable evidence and improve the efficiency of the fingerprint filtering process

Access to primary care and visits to emergency departments in England: a cross-sectional, population-based study

Background The number of visits to hospital emergency departments (EDs) in England has increased by 20% since 2007-08, placing unsustainable pressure on the National Health Service (NHS). Some patients attend EDs because they are unable to access primary care services. This study examined the association between access to primary care and ED visits in England. Methods A cross-sectional, population-based analysis of patients registered with 7,856 general practices in England was conducted, for the time period April 2010 to March 2011. The outcome measure was the number of self-referred discharged ED visits by the registered population of a general practice. The predictor variables were measures of patient-reported access to general practice services; these were entered into a negative binomial regression model with variables to control for the characteristics of patient populations, supply of general practitioners and travel times to health services. Main Result and Conclusion General practices providing more timely access to primary care had fewer self-referred discharged ED visits per registered patient (for the most accessible quintile of practices, RR = 0.898; P<0.001). Policy makers should consider improving timely access to primary care when developing plans to reduce ED utilisation

Using the local density approximation and the LYP, BLYP, and B3LYP functionals within Reference--State One--Particle Density--Matrix Theory

For closed-shell systems, the local density approximation (LDA) and the LYP, BLYP, and B3LYP functionals are shown to be compatible with reference-state one-particle density-matrix theory, where this recently introduced formalism is based on Brueckner-orbital theory and an energy functional that includes exact exchange and a non-universal correlation-energy functional. The method is demonstrated to reduce to a density functional theory when the exchange-correlation energy-functional has a simplified form, i.e., its integrand contains only the coordinates of two electron, say r1 and r2, and it has a Dirac delta function -- delta(r1 - r2) -- as a factor. Since Brueckner and Hartree--Fock orbitals are often very similar, any local exchange functional that works well with Hartree--Fock theory is a reasonable approximation with reference-state one-particle density-matrix theory. The LDA approximation is also a reasonable approximation. However, the Colle--Salvetti correlation-energy functional, and the LYP variant, are not ideal for the method, since these are universal functionals. Nevertheless, they appear to provide reasonable approximations. The B3LYP functional is derived using a linear combination of two functionals: One is the BLYP functional; the other uses exact exchange and a correlation-energy functional from the LDA.Comment: 26 Pages, 0 figures, RevTeX 4, Submitted to Mol. Phy