Experimental population dynamics of Rhabdias bufonis (Nematoda) in toads (Bufo bufo): density-dependence in the primary infection

Density-dependence in worm establishment, numbers, biomass and larval production were examined in primary infections of 0, 10, 40, 80 and 160 larvae of the lung nematode, Rhabdias bufonis in the common toad, Bufo bufo. The infection procedure established 4 non-overlapping levels of infection which persisted until 6 weeks post-infection (p.i.), after which there was an overall decline up to 12 weeks p.i. Worm numbers had no direct effect on adult worm survival but temporal changes in worm weight were density-dependent. Adult worm establishment in the lungs declined significantly as the numbers of worms in the lungs increased. At the lowest exposure dose, 86% of the larvae administered reached maturity in the lungs while at the highest, only 37% did so. Also, the numbers of immature larvae outside the lungs increased as adult worm numbers increased. Both features provide evidence for a threshold limit to the numbers of worms maturing in the lungs. Worm numbers also affected larval output per host and per capita fecundity. A significant positive relationship between per capita fecundity and per capita worm weight suggested that density-dependence acted primarily to constrain the growth of individual worms. Finally, the constraints imposed on worm growth and fecundity were apparently relaxed when worm density decreased, providing evidence for density-dependent flexibility in per capita fecundity. Density-dependence in worm establishment and per capita fecundity are mechanisms which may potentially regulate this host-parasite interaction in the field. Both mechanisms may be functionally related to physical space limitations in the lungs, within which worms must compete for finite nutrient

Ethnic inequalities and pathways to care in psychosis in England: a systematic review and meta-analysis

© The Author(s). 2018Background: As part of a national programme to tackle ethnic inequalities, we conducted a systematic review and meta-analysis of research on ethnic inequalities in pathways to care for adults with psychosis living in England and/or Wales. Methods: Nine databases were searched from inception to 03.07.17 for previous systematic reviews, including forward and backward citation tracking and a PROSPERO search to identify ongoing reviews. We then carried forward relevant primary studies from included reviews (with the latest meta-analyses reporting on research up to 2012), supplemented by a search on 18.10.17 in MEDLINE, Embase, PsycINFO and CINAHL for primary studies between 2012 and 2017 that had not been covered by previous meta-analyses. Results: Forty studies, all conducted in England, were included for our updated meta-analyses on pathways to care. Relative to the White reference group, elevated rates of civil detentions were found for Black Caribbean (OR = 3.43, 95% CI = 2.68 to 4.40, n = 18), Black African (OR = 3.11, 95% CI = 2.40 to 4.02, n = 6), and South Asian patients (OR = 1.50, 95% CI 1.07 to 2.12, n = 10). Analyses of each Mental Health Act section revealed significantly higher rates for Black people under (civil) Section 2 (OR = 1.53, 95% CI = 1.11 to 2.11, n = 3). Rates in repeat admissions were significantly higher than in first admission for South Asian patients (between-group difference p < 0.01). Some ethnic groups had more police contact (Black African OR = 3.60, 95% CI = 2.15 to 6.05, n = 2; Black Caribbean OR = 2.64, 95% CI = 1.88 to 3.72, n = 8) and criminal justice system involvement (Black Caribbean OR = 2.76, 95% CI = 2.02 to 3.78, n = 5; Black African OR = 1.92, 95% CI = 1.32 to 2.78, n = 3). The White Other patients also showed greater police and criminal justice system involvement than White British patients (OR = 1.49, 95% CI = 1.03 to 2.15, n = 4). General practitioner involvement was less likely for Black than the White reference group. No significant variations over time were found across all the main outcomes. Conclusions: Our updated meta-analyses reveal persisting but not significantly worsening patterns of ethnic inequalities in pathways to psychiatric care, particularly affecting Black groups. This provides a comprehensive evidence base from which to inform policy and practice amidst a prospective Mental Health Act reform. Trial registration: CRD42017071663Peer reviewedFinal Published versio

Compulsory admission at first presentation to services for psychosis: does ethnicity still matter? Findings from two population-based studies of first episode psychosis

Objectives Compared with the majority population, those from minority ethnic groups in the UK are more likely to be admitted compulsorily during a first episode of psychosis (FEP). We investigated whether these disparities in pathways in to care continue. Methods We analysed data from two first episode psychosis studies, conducted in the same geographical area in south London 15 years apart: the Aetiology and Ethnicity in Schizophrenia and Other Psychosis (AESOP) and the Clinical Record Interactive Search-First Episode Psychosis (CRIS-FEP) studies. The inclusion/exclusion criteria for case ascertainment for first episode psychosis were identical across the two studies. We performed multivariable logistic regression to estimate odds of compulsory admission by ethnic group, controlling for confounders. Participants Two hundred sixty-six patients with first episode psychosis, aged 18–64 years, who presented to mental health services in south London in 1997–1999 and 446 with FEP who presented in 2010–2012. Results When the two samples were compared, ethnic differences in compulsory admission appear to have remained the same for black African patients, i.e. three times higher than white British in both samples: AESOP (adj. OR = 3.96; 95% CI = 1.80–8.71) vs. CRIS-FEP (adj. OR = 3.12; 95% CI = 1.52–6.35). Black Caribbean patients were three times more likely to be compulsorily admitted in AESOP (adj. OR = 3.20; 95% CI = 1.56–6.54). This was lower in the CRIS-FEP sample (adj. OR = 1.68; 95% CI = 0.71–3.98) and did not meet conventional levels for statistical significance. Conclusion Ethnicity is strongly associated with compulsory admissions at first presentation for psychosis with evidence of heterogeneity across groups, which deserves further research

Crisis resolution teams for people experiencing mental health crises: the CORE mixed-methods research programme including two RCTs

Background Crisis resolution teams (CRTs) seek to avert hospital admissions by providing intensive home treatment for people experiencing a mental health crisis. The CRT model has not been highly specified. CRT care is often experienced as ending abruptly and relapse rates following CRT discharge are high. Aims The aims of CORE (Crisis resolution team Optimisation and RElapse prevention) workstream 1 were to specify a model of best practice for CRTs, develop a measure to assess adherence to this model and evaluate service improvement resources to help CRTs implement the model with high fidelity. The aim of CORE workstream 2 was to evaluate a peer-provided self-management programme aimed at reducing relapse following CRT support. Methods Workstream 1 was based on a systematic review, national CRT manager survey and stakeholder qualitative interviews to develop a CRT fidelity scale through a concept mapping process with stakeholders (n = 68). This was piloted in CRTs nationwide (n = 75). A CRT service improvement programme (SIP) was then developed and evaluated in a cluster randomised trial: 15 CRTs received the SIP over 1 year; 10 teams acted as controls. The primary outcome was service user satisfaction. Secondary outcomes included CRT model fidelity, catchment area inpatient admission rates and staff well-being. Workstream 2 was a peer-provided self-management programme that was developed through an iterative process of systematic literature reviewing, stakeholder consultation and preliminary testing. This intervention was evaluated in a randomised controlled trial: 221 participants recruited from CRTs received the intervention and 220 did not. The primary outcome was re-admission to acute care at 1 year of follow-up. Secondary outcomes included time to re-admission and number of days in acute care over 1 year of follow-up and symptoms and personal recovery measured at 4 and 18 months’ follow-up. Results Workstream 1 – a 39-item CRT fidelity scale demonstrated acceptability, face validity and promising inter-rater reliability. CRT implementation in England was highly variable. The SIP trial did not produce a positive result for patient satisfaction [median Client Satisfaction Questionnaire score of 28 in both groups at follow-up; coefficient 0.97, 95% confidence interval (CI) –1.02 to 2.97]. The programme achieved modest increases in model fidelity. Intervention teams achieved lower inpatient admission rates and less inpatient bed use. Qualitative evaluation suggested that the programme was generally well received. Workstream 2 – the trial yielded a statistically significant result for the primary outcome, in which rates of re-admission to acute care over 1 year of follow-up were lower in the intervention group than in the control group (odds ratio 0.66, 95% CI 0.43 to 0.99; p = 0.044). Time to re-admission was lower and satisfaction with care was greater in the intervention group at 4 months’ follow-up. There were no other significant differences between groups in the secondary outcomes. Limitations Limitations in workstream 1 included uncertainty regarding the representativeness of the sample for the primary outcome and lack of blinding for assessment. In workstream 2, the limitations included the complexity of the intervention, preventing clarity about which were effective elements. Conclusions The CRT SIP did not achieve all its aims but showed potential promise as a means to increase CRT model fidelity and reduce inpatient service use. The peer-provided self-management intervention is an effective means to reduce relapse rates for people leaving CRT care. Study registration The randomised controlled trials were registered as Current Controlled Trials ISRCTN47185233 and ISRCTN01027104. The systematic reviews were registered as PROSPERO CRD42013006415 and CRD42017043048. Funding The National Institute for Health Research Programme Grants for Applied Research programme

Development of a measure of model fidelity for mental health Crisis Resolution Teams

Background Crisis Resolution Teams (CRTs) provide short-term intensive home treatment to people experiencing mental health crisis. Trial evidence suggests CRTs can be effective at reducing hospital admissions and increasing satisfaction with acute care. When scaled up to national level however, CRT implementation and outcomes have been variable. We aimed to develop and test a fidelity scale to assess adherence to a model of best practice for CRTs, based on best available evidence. Methods A concept mapping process was used to develop a CRT fidelity scale. Participants (n = 68) from a range of stakeholder groups prioritised and grouped statements (n = 72) about important components of the CRT model, generated from a literature review, national survey and qualitative interviews. These data were analysed using Ariadne software and the resultant cluster solution informed item selection for a CRT fidelity scale. Operational criteria and scoring anchor points were developed for each item. The CORE CRT fidelity scale was then piloted in 75 CRTs in the UK to assess the range of scores achieved and feasibility for use in a 1-day fidelity review process. Trained reviewers (n = 16) rated CRT service fidelity in a vignette exercise to test the scale’s inter-rater reliability. Results There were high levels of agreement within and between stakeholder groups regarding the most important components of the CRT model. A 39-item measure of CRT model fidelity was developed. Piloting indicated that the scale was feasible for use to assess CRT model fidelity and had good face validity. The wide range of item scores and total scores across CRT services in the pilot demonstrate the measure can distinguish lower and higher fidelity services. Moderately good inter-rater reliability was found, with an estimated correlation between individual ratings of 0.65 (95% CI: 0.54 to 0.76). Conclusions The CORE CRT Fidelity Scale has been developed through a rigorous and systematic process. Promising initial testing indicates its value in assessing adherence to a model of CRT best practice and to support service improvement monitoring and planning. Further research is required to establish its psychometric properties and international applicability

Analyzing the Impacts of Dams on Riparian Ecosystems: A Review of Research Strategies and Their Relevance to the Snake River Through Hells Canyon

River damming provides a dominant human impact on river environments worldwide, and while local impacts of reservoir flooding are immediate, subsequent ecological impacts downstream can be extensive. In this article, we assess seven research strategies for analyzing the impacts of dams and river flow regulation on riparian ecosystems. These include spatial comparisons of (1) upstream versus downstream reaches, (2) progressive downstream patterns, or (3) the dammed river versus an adjacent free-flowing or differently regulated river(s). Temporal comparisons consider (4) pre- versus post-dam, or (5) sequential post-dam conditions. However, spatial comparisons are complicated by the fact that dams are not randomly located, and temporal comparisons are commonly limited by sparse historic information. As a result, comparative approaches are often correlative and vulnerable to confounding factors. To complement these analyses, (6) flow or sediment modifications can be implemented to test causal associations. Finally, (7) process-based modeling represents a predictive approach incorporating hydrogeomorphic processes and their biological consequences. In a case study of Hells Canyon, the upstream versus downstream comparison is confounded by a dramatic geomorphic transition. Comparison of the multiple reaches below the dams should be useful, and the comparison of Snake River with the adjacent free-flowing Salmon River may provide the strongest spatial comparison. A pre- versus post-dam comparison would provide the most direct study approach, but pre-dam information is limited to historic reports and archival photographs. We conclude that multiple study approaches are essential to provide confident interpretations of ecological impacts downstream from dams, and propose a comprehensive study for Hells Canyon that integrates multiple research strategies

Temperature Influences Selective Mortality during the Early Life Stages of a Coral Reef Fish

For organisms with complex life cycles, processes occurring at the interface between life stages can disproportionately impact survival and population dynamics. Temperature is an important factor influencing growth in poikilotherms, and growth-related processes are frequently correlated with survival. We examined the influence of water temperature on growth-related early life history traits (ELHTs) and differential mortality during the transition from larval to early juvenile stage in sixteen monthly cohorts of bicolor damselfish Stegastes partitus, sampled on reefs of the upper Florida Keys, USA over 6 years. Otolith analysis of settlers and juveniles coupled with environmental data revealed that mean near-reef water temperature explained a significant proportion of variation in pelagic larval duration (PLD), early larval growth, size-at-settlement, and growth during early juvenile life. Among all cohorts, surviving juveniles were consistently larger at settlement, but grew more slowly during the first 6 d post-settlement. For the other ELHTs, selective mortality varied seasonally: during winter and spring months, survivors exhibited faster larval growth and shorter PLDs, whereas during warmer summer months, selection on PLD reversed and selection on larval growth became non-linear. Our results demonstrate that temperature not only shapes growth-related traits, but can also influence the direction and intensity of selective mortality

Incidence of Schizophrenia and Other Psychoses in England, 1950–2009: A Systematic Review and Meta-Analyses

Background We conducted a systematic review of incidence rates in England over a sixty-year period to determine the extent to which rates varied along accepted (age, sex) and less-accepted epidemiological gradients (ethnicity, migration and place of birth and upbringing, time). Objectives To determine variation in incidence of several psychotic disorders as above. Data Sources Published and grey literature searches (MEDLINE, PSycINFO, EMBASE, CINAHL, ASSIA, HMIC), and identification of unpublished data through bibliographic searches and author communication. Study Eligibility Criteria Published 1950–2009; conducted wholly or partially in England; original data on incidence of non-organic adult-onset psychosis or one or more factor(s) pertaining to incidence. Participants People, 16–64 years, with first -onset psychosis, including non-affective psychoses, schizophrenia, bipolar disorder, psychotic depression and substance-induced psychosis. Study Appraisal and Synthesis Methods Title, abstract and full-text review by two independent raters to identify suitable citations. Data were extracted to a standardized extraction form. Descriptive appraisals of variation in rates, including tables and forest plots, and where suitable, random-effects meta-analyses and meta-regressions to test specific hypotheses; rate heterogeneity was assessed by the I2-statistic. Results 83 citations met inclusion. Pooled incidence of all psychoses (N = 9) was 31.7 per 100,000 person-years (95%CI: 24.6–40.9), 23.2 (95%CI: 18.3–29.5) for non-affective psychoses (N = 8), 15.2 (95%CI: 11.9–19.5) for schizophrenia (N = 15) and 12.4 (95%CI: 9.0–17.1) for affective psychoses (N = 7). This masked rate heterogeneity (I2: 0.54–0.97), possibly explained by socio-environmental factors; our review confirmed (via meta-regression) the typical age-sex interaction in psychosis risk, including secondary peak onset in women after 45 years. Rates of most disorders were elevated in several ethnic minority groups compared with the white (British) population. For example, for schizophrenia: black Caribbean (pooled RR: 5.6; 95%CI: 3.4–9.2; N = 5), black African (pooled RR: 4.7; 95%CI: 3.3–6.8; N = 5) and South Asian groups in England (pooled RR: 2.4; 95%CI: 1.3–4.5; N = 3). We found no evidence to support an overall change in the incidence of psychotic disorder over time, though diagnostic shifts (away from schizophrenia) were reported. Limitations Incidence studies were predominantly cross-sectional, limiting causal inference. Heterogeneity, while evidencing important variation, suggested pooled estimates require interpretation alongside our descriptive systematic results. Conclusions and Implications of Key Findings Incidence of psychotic disorders varied markedly by age, sex, place and migration status/ethnicity. Stable incidence over time, together with a robust socio-environmental epidemiology, provides a platform for developing prediction models for health service planning