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There is little or no information comparing working experience, including burnout, amongst psychiatry residents internationally. We present preliminary findings from six of the first countries to complete data collection.
Objectives and aims
To obtain data from psychiatric residents in over twenty countries regarding rates of burnout, depression and suicidality and their associations with working conditions and personality traits.
An online survey incorporating the Maslach Burnout Inventory General Survey (MBI-GS), Areas of Work Life Survey (AWLS), Patient Health Questionnaire-9 (PHQ-9), Suicide Ideation and Behaviour Questionnaire (SIBQ), Big Five Inventory - 10 (BFI-10) and questions on demographics and working circumstances was designed, and checked by national co-ordinators for suitability in each participating country, prior to agreeing the final version. This was then translated and back-translated before being sent to participants. A stratified hierarchy sample methodology was developed and used to obtain the best possible study population in each country. This allowed us to maximise participation despite major differences in ease of access to residents across the study countries. The aim of studying the whole resident population was achieved in a large number of countries. Data was then analysed by the study statistician using SPSS. No funding was received for the study.
Results and conclusions
Data from Croatia (n=106), France (n=374), Hungary (n=81), Italy (n=180), Romania (n=52) and United Kingdom (n>2000) revealed marked differences between countries in the factors studied including in working circumstances, rates of burnout and suicidality. The associations discovered may help further improve psychiatric training experience internationally.
The diagnostic boundaries of social anxiety disorder (SAD) are still controversial and recent evidence suggests that the condition could be better understood as a continuum of severity, rather than a strictly circumscribed entity. Current neuroanatomical theories on SAD support the involvement of limbic structures in its pathophysiology, with an emphasis on the amygdala. Thus, the objective of this study was to investigate the hypothesis of volumetric alterations in the amygdala of subjects in different points of the social anxiety spectrum.
The sample consisted of patients with generalized SAD (n=17), subthreshold SAD (increased social anxiety without avoidance; n=13), and healthy controls (n=15). Participants underwent structural magnetic resonance scans and the volume of the bilateral amygdala was manually determined.
Significantly greater volumes of bilateral amygdala were found in socially anxious individuals. Amygdala volumes of subthreshold SAD participants fell between the values found for generalized SAD and healthy controls.
Individuals suffering from SAD have greater amygdala volumes compared to controls and this difference seems to be in agreement with the theoretical conception of SAD as a severity continuum and not as a circumscribed nosological entity.
Persistent psychotic symptoms represent a major challenge for psychiatric care. Basic research has shown that psychotic symptoms are associated with cognitive biases. Metacognitive training (MCT) aims at helping patients to become aware of these biases and to improve problem-solving. Fifty-two participants fulfilling diagnostic criteria of schizophrenia or schizoaffective disorders and persistent delusions and stabilized antipsychotic medication were enrolled in this study. Following baseline assessment patients were randomized either to treatment as usual (TAU) conditions or TAU + MCT. The intervention consisted of eight weekly 1-hour sessions (maximum: 8 hours). Participants were assessed at 8 weeks and 6-months later by blind assessors. Participants were assessed with the Psychotic Symptoms Rating Scales (PSYRATS) and the positive subscale of the PANSS. Between-group differences in post- and pre-test values were significant at a medium effect size in favor of the MCT for the PSYRATS delusion scale and the positive scale of the PANSS both at post and follow-up. The results of this study indicate that MCT training has a surplus antipsychotic effect for patients suffering from schizophrenia-related disorders who demonstrate only a partial response to antipsychotic treatment and that the effect of the intervention persists for at least 6 months after the intervention.
There is little published literature on medical student exchanges in psychiatry.
Aims, objectives and methods
To use a two-week student exchange between Modena, Italy and Norwich, UK to highlight some of the meaningful differences in psychiatric practice between the centers.
White coats - English doctors in general and especially psychiatrists do not wear white coats; in Italy these are almost always worn. Psychiatric nurses in English hospitals likewise do not wear any uniform.
Locations of services - Italian acute psychiatric wards are sited in general hospitals; in England they are usually in a separate location.
Nursing role - Psychiatric nurses in English hospitals are required to play a significant role in decision making around patient care. For example, nurses make almost all decisions regarding admission to hospital. It is also common for nurses to challenge doctors on decisions regarding patient treatments. The role of nurses in Italy is often not a decision-making one, but rather following doctors' orders and providing information.
Wearing white coats can promote a sense of professionalism and help orient patients in a hospital environment, but without these the ward may look less like a hospital and be more comfortable for patients.
Locating psychiatric wards within general hospitals makes consultation between specialties straightforward and may help reduce stigma, but psychiatry-only hospitals may create opportunities for economic efficiencies and improved facilities.
Enhanced nursing roles may be perceived as a possible threat by psychiatrists, yet may strengthen mental health teams and enhance quality of care.
There is a little of awareness about the existence of different methods for teaching undergraduate psychiatry in European countries.
Aims and objectives
To compare two methods of teaching psychiatry through a medical student's eyes during a student exchange.
Comparison of personal experience with traditional education at Modena (Modena University, Italy) and experience with Problem Based Learning (PBL) classes and didactic teaching in Norwich (UEA - Norwich,UK).
Group size- The traditional education system prefers lectures: one professor usually teaches more than 100 students. The PBL model assigns one tutor per group of 10 students. Intensity of work during the year - The traditional education system requires efforts to be concentrated on exams since clinical sessions and lessons can be attended passively. The PBL course requires that each student produce written work and teach this to the other group members weekly. Skill development- Facing comprehensive oral exams forces students in traditional education to focus learning sources and time. The PBL approach enhances debating abilities and improves skills in team working.
Professors' role- Traditional education professors are usually highly qualified in their subject. PBL professors do not necessarily have to be specialists in the subject because their role is mostly as supervisors of the peer-group learning process.
Although at the moment there is no evidence that interactive education methods are more effective in changing doctors' performance it is undeniable that PBL based courses offers more experience in teamwork and in working with a wide range of different colleagues.
While there is suggestion that early onset of psychosis is a determinant of outcome; knowledge regarding correlates of later onset age is more limited. This study explores the characteristics of patients developing psychosis after age 26, towards the end of the usual age range of early intervention programs, in order to identify potential specific needs of such patients.
Two hundred and fifty-six early psychosis patients aged 18–35 were followed-up prospectively over 36 months. Patients with onset after 26 (“later onset”, LO) were compared to the rest of the sample.
LO patients (32% of the sample) had shorter DUP, were less likely to be male, had better premorbid functioning and were more likely to have been exposed to trauma. They had greater insight at presentation and less negative symptoms overall. The trajectories for positive and depressive symptoms were similar in both groups. Evolution of functional level was similar in both groups, but while LO patients recovered faster, they were significantly less likely to return to premorbid functional level.
Later psychosis onset correlates with better premorbid functioning and higher rate of trauma exposure; the latter should therefore be a treatment focus in such patients. LO patients were less likely to return to premorbid functional level, which suggests that current treatment strategies may not be efficient to help patients maintain employment. The possibility of distinct illness mechanisms according to onset age and the more central role for trauma in patients with onset after age 26 needs to be further explored.
Postgraduate medical trainees experience high rates of burnout, but evidence regarding psychiatric trainees is missing. We aim to determine burnout rates among psychiatric trainees, and identify individual, educational and work-related factors associated with severe burnout.
In an online survey psychiatric trainees from 22 countries were asked to complete the Maslach Burnout Inventory (MBI-GS) and provide information on individual, educational and work-related parameters. Linear mixed models were used to predict the MBI-GS scores, and a generalized linear mixed model to predict severe burnout.
This is the largest study on burnout and training conditions among psychiatric trainees to date. Complete data were obtained from 1980 out of 7625 approached trainees (26%; range 17.8–65.6%). Participants were 31.9 (SD 5.3) years old with 2.8 (SD 1.9) years of training. Severe burnout was found in 726 (36.7%) trainees. The risk was higher for trainees who were younger (P < 0.001), without children (P = 0.010), and had not opted for psychiatry as a first career choice (P = 0.043). After adjustment for socio-demographic characteristics, years in training and country differences in burnout, severe burnout remained associated with long working hours (P < 0.001), lack of supervision (P < 0.001), and not having regular time to rest (P = 0.001). Main findings were replicated in a sensitivity analysis with countries with response rate above 50%.
Besides previously described risk factors such as working hours and younger age, this is the first evidence of negative influence of lack of supervision and not opting for psychiatry as a first career choice on trainees’ burnout.
Recent evidences have consistently reported lower glutamate (Glu) levels in various brain regions, including the medial prefrontal cortex (mPFC), in chronic schizophrenia but findings in the early (EP) or in the prodromal phase of the disorder are equivocal. Although regular cannabis use has been associated with an increased risk of subsequent psychosis and with a perturbed Glu signalling, to date, the critical question of whether or not Glu abnormalities exist in EP and are related to cannabis use remains unanswered. Magnetic resonance spectroscopy was used to measure [GlumPFC] of 35 EP subjects (18 of whom were regular cannabis users) and 33 healthy controls (HC). For correlative analysis, neuropsychological performances were scored by a comprehensive cognitive battery. [GlumPFC] was lower in EP users comparing to both HC and EP non-users (P = 0.001 and P = 0.01, respectively), while no differences were observed between HC and EP non-users. In EP users Glu declined with age (r = −0.46; P = 0.04) but this relationship was not observed in non-users. Among neuropsychological profiles, working memory was the only domain that differentiates patients depending on their cannabis use, with users having poorer performances. In summary, our research revealed that cannabis use in EP is associated with Glu decreased levels, which are normally not seen in the early phase of the disorder. This finding is in line with previous 1H-MRS studies in cannabis users without a psychotic disorder and sheds light for the role of cannabis use in the progression of the disease.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Although the onset of bipolar disorder (BD) is usually estimated in early adulthood (Burke et al., 1990; Kessler et al., 1997), it is still not clear which age-specific triggering factors may contribute to the underlying vulnerability.
The present meta-analysis attempts to clarify the number of untreated years of BD, from first symptoms appearance, to first actions carried out by health services (first diagnosis, treatment and hospitalization).
A literature search of three databases PubMed, Web of Science and Psychology and Behavioral Sciences Collection was performed, looking for peer-reviewed publications in English, French, German and Italian language that reported the AOO of BD; the search string adopted was “bipolar and onset”. Standardized mean differences were calculated between (i) mean AOO, operationally defined as onset of first symptoms/episodes, and (ii) mean AOO, operationally defined according to four criteria: first contact with services, date of the diagnosis, first pharmacological treatment, or first hospitalization.
The searches yielded 8710 articles; 2424 of these articles met the inclusion criteria. A final set of 19 studies presenting multiple definitions of AOO has been analyzed, revealing an overall effect size of 6.96 of untreated years (Cohen's d = 0.65)
To our knowledge, this is the first meta-analysis that addresses the definition and the modulation of the AOO in bipolar disorder. Identifying the time-frame of untreated illness is very important for the best planning of timely interventions.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Adult forms of members of the Callodistomidae always parasitize the gallbladder of freshwater fishes and occur in Africa and America. This study provides a description of a new South American species belonging in Prosthenhystera from the gallbladder of a characid fish (Bryconamericus ikaa), and ribosomal gene sequences (28S rDNA and ITS1-5.8S-ITS2) are used to demonstrate molecular differences between the new species and congeners as well as explore interrelationships among congeners. Additionally, the first cytological analysis is conducted for a member of the family to determine chromosome number and arrangement. Prosthenhystera gattii n. sp. most closely resembles Prosthenhystera caballeroi in morphology, but the vitellarium is more extensive reaching anterior to the caecal bifurcation in the new species and the uterus is confined to the hindbody in P. gattii n. sp., whereas it extends to the level of the pharynx in P. caballeroi. Also, the testes, cirrus sac, seminal receptacle and the ratio of body length to width are larger in P. gattii n. sp. Independent Bayesian inference analyses of 28S rDNA and ITS1-5.8S-ITS2 sequence fragments produced phylograms that showed P. gattii n. sp. is more similar to Prosthenhystera obesa + Prosthenhystera oonastica than P. caballeroi + two unidentified species of Prosthenhystera, but with poor posterior probability support for the node in the ITS1-5.8S-ITS2-based phylogram. Further, the genetic distance between P. oonastica and P. gattii n. sp. are the largest among Prosthenhystera spp. Cytological analysis revealed ten metacentric chromosomes, which is fewer than the 12–18 chromosomes present in species from the closely related Gorgoderidae.
We evaluated the relationship between food availability, as the only dietary exposure data available across Africa, and age-standardised cancer incidence rates (ASR) in eighteen countries.
Availability of food groups and dietary energy was considered for five hypothetical time points: years of collection of ASR (T0) and 5, 10, 15 and 20 preceding years (T–5, T–10, T–15, T–20). Ecological correlations adjusted for human development index, smoking and obesity rates were calculated to evaluate the relationship between food availability and ASR of breast, prostate, colorectal, oesophageal, pancreatic, stomach and thyroid cancer.
Red meat was positively correlated with pancreatic cancer in men (T–20: r–20 = 0·61, P < 0·05), stomach cancer in women (T0: r0 = 0·58, P < 0·05), and colorectal cancer in men (T0: r0 = 0·53, P < 0·05) and women (T–20: r–20 = 0·58, P < 0·05). Animal products including meat, animal fats and higher animal-sourced energy supply tended to be positively correlated with breast, colorectal, pancreatic, stomach and thyroid cancer. Alcoholic beverages were positively correlated to oesophageal cancer in men (r0 = 0·69, P < 0·001) and women (r–20 = 0·72, P < 0·001).
The present analysis provides initial insights into the impact of alcoholic beverages, and increasing use of animal over plant products, on the incidence of specific cancers in Africa. The findings support the need for epidemiological studies to investigate the role of diet in cancer development in Africa.
Intake in sugar-rich diets can be limited either via rumen fill or excessive rumen fermentation and source of non-fibre carbohydrate (NFC) in the diet can affect both factors. The aim of the current study was to quantify the effect of partially replacing ground maize (GM) with steam-rolled maize (SRM) or pelleted citrus pulp (PCP) at two concentrate levels in sugarcane-based diets on digestibility, rumen ecosystem and metabolism of Nellore steers. Six rumen-cannulated steers were assigned to a 6 × 6 Latin square, replicated in time, in a 2 × 3 factorial arrangement of treatments with two levels of concentrate (600 or 800 g concentrate/kg dry matter [DM]) and three NFC sources. Each steer within a period was considered an experimental unit. Feeding more concentrate increased total tract digestibility of organic matter and decreased fibre intake and passage rate. It also reduced rumen populations of Fibrobacter succinogenes and Streptococcus bovis and increased Ruminococcus flavefaciens. Substituting PCP for GM increased rumen pH, acetic acid and organic matter digestibility. Feeding PCP also reduced R. flavefaciens and R. amylophilus rumen populations. Substituting SRM for GM increased starch digestibility and rumen propionic acid, but decreased rumen ammonia concentration. Feeding SRM increased rumen populations of Megasphaera elsdenii with the high-concentrate diet but reduced Ruminococcus albus populations at both concentrate levels. In conclusion, partial replacement of GM by PCP decreased intake in sugar-rich diets, while increasing total tract neutral detergent fibre digestibility. Replacement of GM with SRM increases rumen fermentation and total tract digestibility of starch.
Replacing ground maize (GM) with steam-rolled maize typically increases feed efficiency in maize-silage-based diets. However, little is known about optimal carbohydrate supplementation in sugarcane silage-based diets. The objective was to quantify the effect of partially replacing GM with steam-rolled maize (SRM) or pelleted citrus pulp (PCP) at two concentrate levels (600 or 800 g/kg DM) in sugarcane-based diets on feeding behaviour, performance and blood parameters of finishing Nellore bulls. One hundred and eight young bulls were allocated to 36 pens in a randomized block design and fed for 84 d. Feeding 800 g/kg concentrate decreased time spending eating and ruminating, but improved G:F ratio, hot carcass weight and carcass dressing, compared to 600 g/kg concentrate. Bulls fed SRM and PCP diets with 600 g/kg concentrate had lower intake compared to GM. Both final weight and average daily gain decreased when bulls were fed PCP and SRM with 600 g/kg concentrate compared to GM diets, and when fed with PCP and 800 g/kg concentrate. Substituting PCP for GM decreased gain efficiency, carcass weight, rumination time and intake efficiency, indicating that the bulls consumed less feed per hour spent eating. Substituting SRM for GM increased backfat thickness and blood urea concentration. In conclusion, the replacement of GM with PCP reduces intake and enhances selection against large particles, decreasing rumination, performance and final carcass weight and dressing. Replacement of GM with SRM increases blood urea and fat deposition, with no impact on performance.
Keel bone damage (KBD) in laying hens is an important welfare problem in both conventional and organic egg production systems. We aimed to identify possible risk factors for KBD in organic hens by analysing cross-sectional data of 107 flocks assessed in eight European countries. Due to partly missing data, the final multiple regression model was based on data from 50 flocks. Keel bone damage included fractures and/or deviations, and was recorded, alongside with other animal based measures, by palpation and visual inspection of at least 50 randomly collected hens per flock between 52 and 73 weeks of age. Management and housing data were obtained by interviews, inspection and by feed analysis. Keel bone damage flock prevalences ranged from 3% to 88%. Compiled on the basis of literature and practical experience, 26 potential associative factors of KBD went into an univariable selection by Spearman correlation analysis or Mann–Whitney U test (with P<0.1 level). The resulting nine factors were presented to stepwise forward linear regression modelling. Aviary v. floor systems, absence of natural daylight in the hen house, a higher proportion of underweight birds, as well as a higher laying performance were found to be significantly associated with a higher percentage of hens with KBD. The final model explained 32% of the variation in KBD between farms. The moderate explanatory value of the model underlines the multifactorial nature of KBD. Based on the results increased attention should be paid to an adequate housing design and lighting that allows the birds easy orientation and safe manoeuvring in the system. Furthermore, feeding management should aim at sufficient bird live weights that fulfil breeder weight standards. In order to achieve a better understanding of the relationships between laying performance, feed management and KBD further investigations are needed.
The crystal structure of tlapallite has been determined using single-crystal X-ray diffraction and supported by electron probe micro-analysis, powder diffraction and Raman spectroscopy. Tlapallite is trigonal, space group P321, with a = 9.1219(17) Å, c = 11.9320(9) Å and V = 859.8(3) Å3, and was refined to R1 = 0.0296 for 786 reflections with I > 2σ(I). This study resulted from the discovery of well-crystallised tlapallite at the Wildcat prospect, Utah, USA. The chemical formula of tlapallite has been revised to (Ca,Pb)3CaCu6[Te4+3Te6+O12]2(Te4+O3)2(SO4)2·3H2O, or more simply (Ca,Pb)3CaCu6Te4+8Te6+2O30(SO4)2·3H2O, from H6(Ca,Pb)2(Cu,Zn)3(TeO3)4(TeO6)(SO4). The tlapallite structure consists of layers containing distorted Cu2+O6 octahedra, Te6+O6 octahedra and Te4+O4 disphenoids (which together form the new mixed-valence phyllotellurate anion [Te4+3Te6+O12]12−), Te4+O3 trigonal pyramids and CaO8 polyhedra. SO4 tetrahedra, Ca(H2O)3O6 polyhedra and H2O groups fill the space between the layers. Tlapallite is only the second naturally occurring compound containing tellurium in both the 4+ and 6+ oxidation states with a known crystal structure, the other being carlfriesite, CaTe4+2Te6+O8. Carlfriesite is the predominant secondary tellurium mineral at the Wildcat prospect. We also present an updated structure for carlfriesite, which has been refined to R1 = 0.0230 for 874 reflections with I > 2σ(I). This updated structural refinement improves upon the one reported previously by refining all atoms anisotropically and presenting models of bond valence and Te4+ secondary bonding.
Measles is a target for elimination in all six WHO regions by 2020, and over the last decade, there has been considerable progress towards this goal. Surveillance is recognised as a cornerstone of elimination programmes, allowing early identification of outbreaks, thus enabling control and preventing re-emergence. Fever–rash surveillance is increasingly available across WHO regions, and this symptom-based reporting is broadly used for measles surveillance. However, as measles control increases, symptom-based cases are increasingly likely to reflect infection with other diseases with similar symptoms such as rubella, which affects the same populations, and can have a similar seasonality. The WHO recommends that cases from suspected measles outbreaks be laboratory-confirmed, to identify ‘true’ cases, corresponding to measles IgM titres exceeding a threshold indicative of infection. Although serological testing for IgM has been integrated into the fever–rash surveillance systems in many countries, the logistics of sending in every suspected case are often beyond the health system's capacity. We show how age data from serologically confirmed cases can be leveraged to infer the status of non-tested samples, thus strengthening the information we can extract from symptom-based surveillance. Applying an age-specific confirmation model to data from three countries with divergent epidemiology across Africa, we identify the proportion of cases that need to be serologically tested to achieve target levels of accuracy in estimated infected numbers and discuss how this varies depending on the epidemiological context. Our analysis provides an approach to refining estimates of incidence leveraging all available data, which has the potential to improve allocation of resources, and thus contribute to rapid and efficient control of outbreaks.
Introduction: Delays in transfer to an in-patient bed of admitted patients boarded in the ED has been identified as one of the chief drivers of ED overcrowding. Our study aims to replicate findings from a previous study in identifying patient characteristics associated with increased boarding time, and the impact of increased boarding time on in-patient length of stay (IPLOS). Methods: We conducted a retrospective single-centre observational study during the period between January 1, 2015 December 31, 2015 at a very high volume community hospital (~ 75,000 ED visits/year). All patients admitted from the ED to Medicine, Pediatrics, Surgery, and Critical Care were identified. The mean time to in-patient bed (TTB), as well as patient-specific and institutional factors that were associated with prolonged boarding times ( 12 hours) were identified. Mean IP LOS was calculated for those with prolonged boarding times and compared to those without prolonged boarding times. Results: There were 8,096 unique admissions during the study period. Patients admitted to the Medicine service exhibited significantly higher boarding times than those admitted to other services, with a mean boarding time of 17.4 hrs, as compared to 4.2 hrs, 5.7 hrs, and 4.0 hrs for those admitted to Surgery, Critical Care and Pediatrics respectively. Within Medicine patients, there was a statistically significant greater odds of prolonged boarding time for patients who were older, had a greater comorbidity burden, and required more specialized in-patient care (i.e. an isolation bed or telemetry bed). Medicine patients with prolonged boarding times also experienced 0.7 days longer IP LOS, even after correcting for age and comorbidity (mean adjusted IP LOS 10.6 days versus 11.3 days). Conclusion: Within our study period, older, sicker patients and those patients requiring more resource-intensive in-patient care have the longest ED boarding times. These prolonged ‘boarding’ times are associated with significantly increased IP LOS.
L. J. Spilker, NASA Jet Propulsion Laboratory Pasadena, California, USA,
C. Ferrari, Université Paris-Diderot Paris, FRANCE,
N. Altobelli, European Space Agency Madrid, SPAIN,
S. Pilorz, SETI Institute Mountain View, California, USA,
R. Morishima, University of California, Los Angeles Los Angeles, California, USA
Our view of planetary ring particles and the characteristics of their thermal emission has undergone a major paradigm shift since the arrival of Cassini at Saturn. Our understanding of the microstructure and microphysics of the rings has evolved from rings randomly filled with individual particles to Saturn's A and B rings containing particles that tend to clump into transient structures of characteristic sizes and orientations. The dynamics and evolution of rings strongly depend on the outcome of interparticle collisions and on the self-gravity of the rings. Energy loss, mass transfer, and sticking probability for relevant impact velocities will favor either aggregation or disruption and erosion of particles, modifying the size distribution and velocity dispersion, and thus the dynamics and structure of the rings.
The thermal response of a ring is determined by absorbed and emitted radiation or conducted heat within the particles. The radiation source functions depend upon the ring structure. Energy sources include direct, reflected and scattered solar light, mutual heating by neighboring ring particles, and thermal and visible radiation from Saturn. Because of mutual shading and heating between particles, the thermal emission is determined not only by the physical properties of the ring particles, but also by the structural and dynamical properties of the ring disk itself. Friction in mutual dissipative collisions between particles, due to their irregular surfaces, transforms orbital kinetic energy into spin. The particle surface temperature and its thermal emission are expected to vary on the surface along the rotation axis and azimuthally. Ring particles, as they collide into one another, are tumbling around the ring mid-plane with a vertical excursion governed by the local ring dynamics. The thermal history of a particle along its orbit is then an indicator of vertical dynamics. The particle is conditioned by the time it spends in sunlight and in the planetary shadow. At the exit of the shadow, its ability to warm up is a function of the thermal inertia. Any difference in the heating curves between the lit and unlit sides should reveal the time each particle spends on each side.
Measles eradication efforts have been successful at achieving elimination in many countries worldwide. Such countries actively work to maintain this elimination by continuing to improve coverage of two routine doses of measles vaccine following measles elimination. While improving measles vaccine coverage is always beneficial, we show, using a steady-state analysis of a dynamical model, that the correlation between populations receiving the first and second routine dose also has a significant impact on the population immunity achieved by a specified combination of first and second dose coverage. If the second dose is administered to people independently of whether they had the first dose, high second-dose coverage improves the proportion of the population receiving at least one dose, and will have a large effect on population immunity. If the second dose is administered only to people who have had the first dose, high second-dose coverage reduces the rate of primary vaccine failure, but does not reach people who missed the first dose; this will therefore have a relatively small effect on population immunity. When doses are administered dependently, and assuming the first dose has higher coverage, increasing the coverage of the first dose has a larger impact on population immunity than does increasing the coverage of the second. Correlation between vaccine doses has a significant impact on the level of population immunity maintained by current vaccination coverage, potentially outweighing the effects of age structure and, in some cases, recent improvements in vaccine coverage. It is therefore important to understand the correlation between vaccine doses as such correlation may have a large impact on the effectiveness of measles vaccination strategies.