Predicting Gout Flares in People Starting Allopurinol Using the Start-Low Go-Slow Dose Escalation Strategy.

OBJECTIVE: The study objective was to determine predictors of gout flare when commencing allopurinol using the "start-low go-slow" dose escalation strategy. METHODS: A post hoc analysis of a 12-month double-blind placebo-controlled noninferiority trial with participants randomized 1:1 to colchicine 0.5 mg daily or placebo for the first six months was undertaken. Multivariate logistic regression models were used to identify independent predictors of gout flares in the first and last six months of the trial. RESULTS: Multivariable analysis revealed a significant association between risk of a gout flare in the first six months and flare in the month before starting allopurinol (odds ratio [OR] 2.65, 95% confidence interval [CI] 1.36-5.17) and allopurinol 100 mg starting dose (OR 3.21, 95% CI 1.41-7.27). The predictors of any gout flares in the last six months of the trial, after stopping colchicine or placebo, were having received colchicine (OR 2.95, 95% CI 1.48-5.86), at least one flare in the month before stopping study drug (OR 5.39, 95% CI 2.21-13.15), and serum urate ≥0.36 mmol/L at month 6 (OR 2.85, 95% CI 1.14-7.12). CONCLUSION: Anti-inflammatory prophylaxis when starting allopurinol using the "start-low go-slow" dose escalation strategy may be best targeted at those who have had a gout flare in the month before starting allopurinol and are commencing allopurinol 100 mg daily. For those with ongoing gout flares during the first six months of starting allopurinol who have not yet achieved serum urate target, a longer period of prophylaxis may be required.

Is colchicine prophylaxis required with start-low go-slow allopurinol dose escalation in gout? A non-inferiority randomised double-blind placebo-controlled trial.

OBJECTIVES: To determine whether placebo is non-inferior to low-dose colchicine for reducing gout flares during the first 6 months of allopurinol using the 'start-low go-slow' dose approach. METHODS: A 12-month double-blind, placebo-controlled non-inferiority trial was undertaken. Adults with at least one gout flare in the preceding 6 months, fulfilling the American College of Rheumatology (ACR) recommendations for starting urate-lowering therapy and serum urate ≥0.36 mmol/L were recruited. Participants were randomised 1:1 to colchicine 0.5 mg daily or placebo for the first 6 months. All participants commenced allopurinol, increasing monthly to achieve target urate <0.36 mmol/L. The primary efficacy outcome was the mean number of gout flares/month between 0 and 6 months, with a prespecified non-inferiority margin of 0.12 gout flares/month. The primary safety outcome was adverse events over the first 6 months. RESULTS: Two hundred participants were randomised. The mean (95% CI) number of gout flares/month between baseline and month 6 was 0.61 (0.47 to 0.74) in the placebo group compared with 0.35 (0.22 to 0.49) in the colchicine group, mean difference 0.25 (0.07 to 0.44), non-inferiority p=0.92. There was no difference in the mean number of gout flares/month between randomised groups over the 12-month period (p=0.68). There were 11 serious adverse events in 7 participants receiving colchicine and 3 in 2 receiving placebo. CONCLUSIONS: Placebo is not non-inferior to colchicine in prevention of gout flares in the first 6 months of starting allopurinol using the 'start-low go-slow' strategy. After stopping colchicine, gout flares rise with no difference in the mean number of gout flares/month between groups over a 12-month period. TRIAL REGISTRATION NUMBER: ACTRN 12618001179224.

Giant cell arteritis: A population-based retrospective cohort study exploring incidence and clinical presentation in Canterbury, Aotearoa New Zealand.

Background/aim: To determine the epidemiology and clinical features of giant cell arteritis (GCA) in Canterbury, Aotearoa New Zealand, with a particular focus on extra-cranial large vessel disease. Methods: Patients with GCA were identified from radiology and pathology reports, outpatient letters and inpatient hospital admissions in the Canterbury New Zealand from 1 June 2011 to 31 May 2016. Data was collected retrospectively based on review of electronic medical records. Results: There were 142 cases of GCA identified. 65.5% of cases were female with a mean age of 74.2 years. The estimated population incidence for biopsy-proven GCA was 10.5 per 100,000 people over the age of 50 and incidence peaked between 80 and 84 years of age. 10/142 (7%) people were diagnosed with large vessel GCA, often presenting with non-specific symptoms and evidence of vascular insufficiency including limb claudication, vascular bruits, blood pressure and pulse discrepancy, or cerebrovascular accident. Those with limited cranial GCA were more likely to present with the cardinal clinical features of headache and jaw claudication. Patients across the two groups were treated similarly, but those with large vessel disease had greater long-term steroid burden. Rates of aortic complication were low across both groups, although available follow-up data was limited. Conclusion: This study is the first of its kind to describe the clinical characteristics of large vessel GCA in a New Zealand cohort. Despite small case numbers, two distinct subsets of disease were recognized, differentiating patients with cranial and large vessel disease. Our results suggest that utilization of an alternative diagnostic and therapeutic approach may be needed to manage patients with large vessel disease.

The Prevalence, Magnitude, and Reversibility of Elevated Liver Enzyme Activities in Hyperthyroid Cats Presenting for Iodine-131 Treatment.

OBJECTIVES: The primary objective of this study was to report the prevalence and magnitude of elevated liver enzyme activity in feline hyperthyroidism using a large cohort of cats presenting for iodine-131 treatment. The secondary objective was to determine if elevated liver enzyme activity was a reversible process following successful iodine-131 treatment. METHODS: Cases that presented for a single iodine-131 treatment were retrospectively reviewed. Short-term and long-term follow-up clinicopathologic data was then reviewed for the secondary objective. RESULTS: Two hundred seventeen hyperthyroid cats met the inclusion criteria for the primary objective. In total, 123/217 (56.7%) of the cats had at least one liver enzyme elevation on their chemistry panel, with alanine transaminase activity being the most common. All cats who were successfully treated with iodine-131 had liver enzyme activity within the reference range at short-term follow-up and long-term follow-up points. CONCLUSION AND RELEVANCE: Our study demonstrates that elevated liver values are common in cats presenting for iodine-131 treatment. Additionally, our study demonstrates that even when liver values are markedly elevated prior to treatment, the liver enzyme activity will return to normal after successful resolution of hyperthyroidism using iodine-131 treatment. Investigation into hepatobiliary disease and liver function tests for cats with a diagnosis of hyperthyroidism may be unnecessary as the liver values will likely return to normal with successful iodine-131 treatment.

"There Is No (Where a) Face Like Home": Recognition and Appraisal Responses to Masked Facial Dialects of Emotion in Four Different National Cultures.

The theory of universal emotions suggests that certain emotions such as fear, anger, disgust, sadness, surprise and happiness can be encountered cross-culturally. These emotions are expressed using specific facial movements that enable human communication. More recently, theoretical and empirical models have been used to propose that universal emotions could be expressed via discretely different facial movements in different cultures due to the non-convergent social evolution that takes place in different geographical areas. This has prompted the consideration that own-culture emotional faces have distinct evolutionary important sociobiological value and can be processed automatically, and without conscious awareness. In this paper, we tested this hypothesis using backward masking. We showed, in two different experiments per country of origin, to participants in Britain, Chile, New Zealand and Singapore, backward masked own and other-culture emotional faces. We assessed detection and recognition performance, and self-reports for emotionality and familiarity. We presented thorough cross-cultural experimental evidence that when using Bayesian assessment of non-parametric receiver operating characteristics and hit-versus-miss detection and recognition response analyses, masked faces showing own cultural dialects of emotion were rated higher for emotionality and familiarity compared to other-culture emotional faces and that this effect involved conscious awareness.

Adjusted calcium concentration as a predictor of ionized hypocalcemia in hypoalbuminemic dogs.

BACKGROUND: Ionized calcium (iCa) is the biologically active fraction of total calcium (tCa) with clinical relevance to evaluate calcium homeostasis, but not all primary veterinarians have access to serum iCa. Formulas that adjust tCa to correct for variability in serum protein concentrations were not designed to predict iCa and are considered unreliable surrogates for iCa. OBJECTIVES: To determine whether adjusted calcium concentration (aCa) can predict ionized hypocalcemia in hypoalbuminemic dogs without hyperphosphatemia. ANIMALS: A total of 262 hypoalbuminemic dogs without hyperphosphatemia. METHODS: Retrospective review of paired tCa and iCa. Patients were included if serum albumin concentration was ≤2.5 g/L and serum phosphorus concentration was ≤5 mg/dL. The aCa was calculated using tCa (mg/dL) - serum albumin concentration (g/dL) + 3.5 (g/dL). Sensitivity, specificity, positive (PPVs) and negative (NPVs) predictive values, and accuracy were determined for tCa and aCa at predicting any (<1.13 mmol/L) and moderate (<1.02 mmol/L) ionized hypocalcemia. Patients also were stratified into mild-to-moderate (2.0-2.5 g/dL) and severe hypoalbuminemia (<2.0 g/dL). RESULTS: A total of 4296 dogs had paired results of which 262 met the inclusion criteria. Of these, 35 (13.4%) dogs had iCa < 1.13 mmol/L and 13 dogs (5.0%) had concentrations <1.02 mmol/L. The sensitivity, specificity, NPVs and PPVs of a decreased tCa and aCa for detecting moderate ionized hypocalcemia were 100% and 92.3%, 57.8% and 94.8%, 100% and 99.6%, and 11.0% and 48.2%, respectively, and accuracy was 60.0% and 94.7%, respectively. CONCLUSIONS: A low aCa was useful to detect ionized hypocalcemia in hypoalbuminemic nonhyperphosphatemic dogs. A normal aCa indicated that moderate ionized hypocalcemia was unlikely.

Synthesis, characterisation and thermo-physical properties of highly stable graphene oxide-based aqueous nanofluids for potential low-temperature direct absorption solar applications.

Two types of highly stable 0.1% graphene oxide-based aqueous nanofluids were synthesised and investigated. The first nanofluid (GO) was prepared under the influence of ultrasonic irradiation without surfactant. The second nanofluid was treated with tetra ethyl ammonium hydroxide to reduce the graphene oxide to form reduced graphene oxide (RGO) during ultrasonic irradiation. The GO and RGO powders were characterised by various techniques such as field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction and Raman. Also UV-visible absorption spectroscopy was carried out and band gap energies were determined. Optical band gap energies for indirect transitions ranged from 3.4 to 4.4 eV and for direct transitions they ranged between 2.2 and 3.7 eV. Thermal conductivity measurements of the GO-based aqueous nanofluid revealed an enhancement of 9.5% at 40 °C compared to pure water, while the RGO-based aqueous nanofluid at 40 °C had a value 9.23% lower than pure water. Furthermore, the photothermal response of the RGO-based aqueous nanofluid had a temperature increase of 13.5 °C, (enhancement of 60.2%) compared to pure water, the GO-based aqueous nanofluid only displayed a temperature rise of 10.9 °C, (enhancement of 46.6%) after 20 min exposure to a solar irradiance of 1000 W m-2. Both nanofluid types displayed good long-term stability, with the GO-based aqueous nanofluid having a zeta potential of 30.3 mV and the RGO-based aqueous nanofluid having a value of 47.6 mV after 6 months. The good dispersion stability and photothermal performance makes both nanofluid types very promising working fluids for low-temperature direct absorption solar collectors.

Individual conscious and unconscious perception of emotion: Theory, methodology and applications.

In this manuscript we review a seminal debate related to subliminality and concerning the relationship of consciousness, unconsciousness, and perception. We present the methodological implementations that contemporary psychology introduced to explore this relationship, such as the application of unbiased self-report metrics and Bayesian analyses for assessing detection and discrimination. We present evidence concerning an unaddressed issue, namely, that different participants and stimulus types require different thresholds for subliminal presentation. We proceed to a step-by-step experimental illustration of a method involving individual thresholds for the presentation of masked emotional faces. We show that individual thresholds provide Bayesian evidence for null responses to the presented faces. Conversely, we show in the same database that when applying established but biased non-individual criteria for subliminality physiological changes occur and relate - correctly, and most importantly incorrectly - to perception concerning the emotional type, and the valence and intensity of a presented masked emotional face.

The effect of a secondary task on drivers' gap acceptance and situational awareness at junctions.

The current studies explored the roles of the visuospatial and phonological working memory subsystems on drivers' gap acceptance and memory for approaching vehicles at junctions. Drivers' behaviour was measured in a high-fidelity driving simulator when at a junction, with, and without a visuospatial or phonological load. When asked to judge when to advance across the junction, gap acceptance thresholds, memory for vehicles and eye movements were not different when there was a secondary task compared to control. However, drivers' secondary task performance was more impaired in the visuospatial than phonological domain. These findings suggest that drivers were able to accept impairment in the secondary task while maintaining appropriate safety margins and situational awareness. These findings can inform the development of in-car technologies, improving the safety of road users at junctions. Practitioner summary: Despite research indicating that concurrent performance on working memory tasks impairs driving, a matched visuospatial or phonological memory load did not change drivers' gap acceptance or situational awareness at junctions. Drivers displayed appropriate compensatory behaviour by prioritising the driving task over the visuospatial secondary task. Abbreviations: ROW: right of way; RIG: random time interval generation.

Evaluating the impact of Heavy Goods Vehicle driver monitoring and coaching to reduce risky behaviour.

Determining the impact of driver-monitoring technologies to improve risky driving behaviours allows stakeholders to understand which aspects of onboard sensors and feedback need enhancement to promote road safety and education. This study investigates the influence of camera monitoring on Heavy Goods Vehicle (HGV) drivers' risky behaviours. We also assess whether monitoring affects individual driving events further when coupled with safe driving practices coaching. We evaluate the outcome of those practices on three telematics incidents heavily reliant on driving errors and violations, i.e., the number of vehicle harsh braking, harsh cornering and over speeding incidents. The objective is to understand how frequently individual incidents caused by risky driving behaviour occur (a) without camera monitoring and without any coaching; (b) after camera installation; and (c) after camera installation and coaching. We investigate two commercial HGV companies (Company 1 and Company 2) with 263 and 269 vehicles, respectively, over a 16 months period, from which the first 8 months contain data collected before the installation of cameras (baseline) and the rest of the dataset contains incident counts after the installation of cameras (intervention). Company 1 provides coaching during the intervention phase while Company 2 does not offer coaching. Our analysis considers the baseline and the intervention phases during the same seasons to eliminate any possible bias due to the influence of weather on driving behaviour. Results show an overall significant reduction in the mean frequency of harsh braking incidents from baseline to intervention by 16.82% in Company 1 and 4.62% in Company 2, and a significant reduction in the mean frequency of over speeding incidents from baseline to intervention by 34.29% in Company 1 and 28.13% in Company 2. Furthermore, the effect of coaching has a significant difference in reducing the frequency of harsh braking (p = .011) and harsh cornering (p < .001) compared to just camera monitoring. These results suggest that coaching interventions are more effective in reducing driving errors while monitoring reduces both driving errors and violations.

"The Harder One Tries ": Findings and Insights From the Application of Covert Response Pressure Assessment Technology in Three Studies of Visual Perception.

In this article, we present a force measuring method for assessing participant responses in studies of visual perception. We present a device disguised as a mouse pad and designed to measure mouse-click-pressure and click-press-to-release-time responses by unaware, as regards to the physiological assessment, participants. The aim of the current technology, in the current studies, was to provide a physiological assessment of confidence and task difficulty. We tested the device in three experiments. The studies comprised of a gender-recognition study using morphed male and female faces, a visual suppression study using backwards masking, and a target-search study that included deciding whether a letter was repeated in a subsequently presented letter string. Across all studies, higher task difficulty was associated with higher click-release-time responses. Higher task difficulty was, intriguingly, also associated with lower click pressure. Higher confidence ratings were consistently associated with higher click pressure and shorter click-release time across all experiments. These findings suggest that the current technology can be used to assess responses relating to task difficulty and participant confidence in studies of visual perception. We suggest that the assessment of release times can also be implemented using standard equipment, and we provide manual and easy-to-use code for the implementation.

Allopurinol hypersensitivity: Pathogenesis and prevention.

Allopurinol, a first line urate-lowering therapy, has been associated with serious cutaneous reactions that have a high mortality. A number of risk factors for these serious adverse reactions have been identified including ethnicity, HLA-B∗5801 genotype, kidney impairment, allopurinol starting dose, and concomitant diuretic use. There is a complex interplay between these risk factors, which may (albeit rarely) lead to allopurinol-related serious adverse events. Although oxypurinol, the active metabolite of allopurinol, has been implicated, there is no defined drug concentration at which the reaction will occur. There is no specific treatment other than the cessation of allopurinol and supportive care. Whether hemodialysis, which rapidly removes oxypurinol, improves outcomes remains to be determined. Strategies to help reduce this risk are therefore important, which includes screening for HLA-B∗5801 in high-risk individuals, commencing allopurinol at low dose, and educating patients about the signs and symptoms of severe cutaneous adverse reactions, and what to do if they occur.

Lack of effect of tart cherry concentrate dose on serum urate in people with gout.

OBJECTIVES: Cherry concentrate has been suggested to reduce serum urate (SU) and gout flares. The aims of this study were to determine the magnitude of the effect of tart cherry concentrate on SU in people with gout, the most effective dose of tart cherry concentrate for lowering SU, and adverse effects. METHODS: Fifty people with gout and SU > 0.36 mmol/l were recruited. Half were on allopurinol and half were on no urate-lowering therapy. Participants were randomized to receive tart cherry juice concentrate: placebo, 7.5 ml, 15 ml, 22.5 ml or 30 ml twice daily for 28 days. Blood samples were taken at baseline, then at 1, 3 and 5 h post cherry and then on days 1, 3, 7, 14, 21 and 28. The area under the curve for SU was calculated over the 28-day study period. RESULTS: Cherry concentrate dose had no significant effect on reduction in SU area under the curve, urine urate excretion, change in urinary anthocyanin between day 0 and day 28, or frequency of gout flares over the 28-day study period (P = 0.76). There were 24 reported adverse events, with only one (hyperglycaemia) considered possibly to be related to cherry concentrate. Allopurinol use did not modify the effect of cherry on SU or urine urate excretion. CONCLUSION: Tart cherry concentrate had no effect on SU or urine urate excretion. If there is an effect of cherry concentrate on gout flares over a longer time period, it is not likely to be mediated by reduction in SU. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR), https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=368887, ANZCTR 12615000741583).

"I can see you; I can feel it; and vice-versa": consciousness and its relation to emotional physiology.

In this paper, we explore whether masked emotional faces can elicit changes in physiology without awareness. We also explore whether emotional miss-discrimination involves the physiological correlates associated with the perception of an emotion. We adjust the discrimination threshold of presentation per participant and stimulus type to chance-level performance using hit rates and receiver-operating characteristics (ROC). We assess subliminality using an adjusted Bayesian criterion for awareness (A = .167). We measure skin-conductance, heart-rate, facial-emotional and engagement-task force-pressure responses to masked fearful, angry, happy, sad and neutral faces. We report that when faces were subjectively adjusted using unbiased ROC criteria for awareness, we found non-significant differences between emotions and Bayesian evidence for null responses. Hit-rate adjustments were associated with physiological changes for hits and misses for fearful, angry and happy faces. For misses for discrimination performance, participants could correctly appraise the valence and arousal of the presented face. Miss-discrimination for seeing a fearful face when presented with innocuous cues was also associated with high arousal responses. These findings suggest that if physiological arousal is elicited during the presentation of masked emotion, conscious assessment is, upon explicit post-trial inquiry, involved in the evaluation of the elicited emotion and the emotional elicitor.

Anger and hostility: are they different? An analytical exploration of facial-expressive differences, and physiological and facial-emotional responses.

Previous research has proposed the exploratory hypotheses that hostility could differ from anger in the sense that it involves higher possibility for inflicting physical harm while anger could involve higher frustration and stress compared to hostility. Based on these hypotheses we tested whether there are expressive differences and discrete emotional responses between angry and hostile faces. We used participant assessment to preselect faces. We found that using action unit analysis, faces labelled as angry and hostile revealed differences in expressive characteristics and that hostile faces were - as predicted - rated by the participants higher for the intent to inflict physical harm. Subsequently, we presented these faces, as well as fearful, sad and neutral faces, overtly and using masking and measured skin-conductance, heart-rate and facial-emotional responses. We found that in both conditions faces expressing hostility led to higher physiological arousal. Detection of a face was a necessary condition for physiological responses to angry and hostile expressions when faces were presented using masking. We found that during overt presentations, hostility elicited fearful facial-emotional responses while anger elicited mirroring responses. Our findings suggest that hostility is a fear-eliciting emotion related to anger with distinguishable expressive characteristics.

Relationships Between Allopurinol Dose, Oxypurinol Concentration and Urate-Lowering Response-In Search of a Minimum Effective Oxypurinol Concentration.

The aims of this study were to determine factors that predict serum urate (SU) lowering response to allopurinol and the conversion of allopurinol to oxypurinol, and to determine a minimum therapeutic oxypurinol concentration. Data from 129 participants in a 24-month open, randomized, controlled, parallel-group, comparative clinical trial were analyzed. Allopurinol dose, SU, and plasma oxypurinol concentrations were available at multiple time points. The slope for the association between allopurinol dose and SU was calculated as a measure of sensitivity to allopurinol. The slope for the association between allopurinol dose and oxypurinol was calculated as a measure of allopurinol metabolism. Receiver operating characteristic (ROC) curves were used to identify a minimum oxypurinol concentration predictive of SU < 6 mg/dL. There was a wide range of SU concentrations for each allopurinol dose. The relationship between sensitivity to allopurinol and allopurinol metabolism for each 100 mg allopurinol dose increase varied between individuals. Body mass index (P = 0.023), creatinine clearance (CrCL; P = 0.037), ABCG2 Q141K (P = 0.019), and SU (P = 0.004) were associated with sensitivity to allopurinol. The minimum oxypurinol concentration for achieving the urate target was found to be about 104 µmol/L, but predictive accuracy was poor (ROC curve area under the curve (AUC) 0.65). The minimum therapeutic oxypurinol concentration was found to increase with decreasing renal function. Although there is a positive relationship between change in oxypurinol and change in SU concentration, a minimum therapeutic oxypurinol is dependent on CrCL and cannot reliably predict SU target. Other variables, including ABCG2 Q141K genotype, impact on sensitivity to allopurinol (ACTRN12611000845932).

How does drivers' visual search change as a function of experience? A systematic review and meta-analysis.

Novice drivers are statistically over-represented in reported road crashes, with recent evidence suggesting that some of this increased crash involvement may be a result of limitations in their cognitive processing. Such processing has typically been measured by recording drivers' patterns of eye movements, however, the exact ways in which eye movements are reported and interpreted varies substantially between different studies in the literature. Therefore, the objective of this systematic review was to investigate whether novice drivers and experienced drivers do differ in clear and reproducible ways in their visual search. Studies were identified through searches of Web of Science, Medline, TRID Database, and the TRB Research in Progress Database, with no restrictions on publication status. Studies were included if they compared the visual search of a novice driver group (<3 years driving experience) and an experienced driver group (>3 years driving experience) using an eye tracking method and reported at least one of the following four visual search outcomes: fixation durations, horizontal spread of search, vertical spread of search and number of fixations. Two reviewers independently screened searches and assessed the full texts of potentially included studies. Of the 235 studies initially identified 18 were included in the review, with 13 studies reporting sufficient data to be included in the meta-analysis for at least one outcome measure. Given that the included studies deployed a range of method types, additional sub-group analyses were conducted using this factor. Sensitivity analyses were also conducted by temporarily removing extreme experience groups (e.g. driving instructors and learner drivers) in order to test the effect of different levels of experience and training. The meta-analyses, along with support from results discussed narratively, revealed that novice drivers have a narrower horizontal spread of search compared to experienced drivers, however, there were no overall differences in fixation durations, vertical spread of search or number of fixations when the studies were pooled together. These findings have important primary implications for the development of novice training interventions, with novice drivers needing to develop a broader horizontal spread of visual search, but not to necessarily learn to fixate further down the road. Subgroup analyses also provided considerations for future research studies in terms of the experience of the driver groups, and the method type used.

The 'Saw but Forgot' error: A role for short-term memory failures in understanding junction crashes?

Motorcyclists are involved in an exceptionally high number of crashes for the distance they travel, with one of the most common incidents being where another road user pulls out into the path of an oncoming motorcycle frequently resulting in a fatal collision. These instances have previously been interpreted as failures of visual attention, sometimes termed 'Look but Fail to See' (LBFTS) crashes, and interventions have focused on improving drivers' visual scanning and motorcycles' visibility. Here we show from a series of three experiments in a high-fidelity driving simulator, that when drivers' visual attention towards and memory for approaching vehicles is experimentally tested, drivers fail to report approaching motorcycles on between 13% and 18% of occasions. This happens even when the driver is pulling out into a safety-critical gap in front of the motorcycle, and often happens despite the driver having directly fixated on the oncoming vehicle. These failures in reporting a critical vehicle were not associated with how long the driver looked at the vehicle for, but were associated with drivers' subsequent visual search and the time that elapsed between fixating on the oncoming vehicle and pulling out of the junction. Here, we raise the possibility that interference in short-term memory might prevent drivers holding important visual information during these complex manoeuvres. This explanation suggests that some junction crashes on real roads that have been attributed to LBFTS errors may have been misclassified and might instead be the result of 'Saw but Forgot' (SBF) errors. We provide a framework for understanding the role of short-term memory in such situations, the Perceive Retain Choose (PRC) model, as well as novel predictions and proposals for practical interventions that may prevent this type of crash in the future.