Reassessing the observational evidence for nitrogen deposition impacts in acid grassland: spatial Bayesian linear models indicate small and ambiguous effects on species richness

Nitrogen deposition (Ndep) is considered a significant threat to plant diversity in grassland ecosystems around the world. The evidence supporting this conclusion comes from both observational and experimental research, with “space-for-time” substitution surveys of pollutant gradients a significant portion of the former. However, estimates of regression coefficients for Ndep impacts on species richness, derived with a focus on causal inference, are hard to locate in the observational literature. Some influential observational studies have presented estimates from univariate models, overlooking the effects of omitted variable bias, and/or have used P-value-based stepwise variable selection (PSVS) to infer impacts, a strategy known to be poorly suited to the accurate estimation of regression coefficients. Broad-scale spatial autocorrelation has also generally been unaccounted for. We re-examine two UK observational datasets that have previously been used to investigate the relationship between Ndep and plant species richness in acid grasslands, a much-researched habitat in this context. One of these studies (Stevens et al., 2004, Science, 303: 1876–1879) estimated a large negative impact of Ndep on richness through the use of PSVS; the other reported smaller impacts (Maskell et al., 2010, Global Change Biology, 16: 671–679), but did not explicitly report regression coefficients or partial effects, making the actual size of the estimated Ndep impact difficult to assess. We reanalyse both datasets using a spatial Bayesian linear model estimated using integrated nested Laplace approximation (INLA). Contrary to previous results, we found similar-sized estimates of the Ndep impact on plant richness between studies, both with and without bryophytes, albeit with some disagreement over the most likely direction of this effect. Our analyses suggest that some previous estimates of Ndep impacts on richness from space-for-time substitution studies are likely to have been over-estimated, and that the evidence from observational studies could be fragile when confronted with alternative model specifications, although further work is required to investigate potentially nonlinear responses. Given the growing literature on the use of observational data to estimate the impacts of pollutants on biodiversity, we suggest that a greater focus on clearly reporting important outcomes with associated uncertainty, the use of techniques to accou URL link.nt for spatial autocorrelation, and a clearer focus on the aims of a study, whether explanatory or predictive, are all required

Stopping clinical trials early for futility: retrospective analysis of several randomised clinical studies

Background: Many clinical trials show no overall benefit. We examined futility analyses applied to trials with different effect sizes. Methods: Ten randomised cancer trials were retrospectively analysed; target sample size reached in all. The hazard ratio indicated no overall benefit (n=5), or moderate (n=4) or large (n=1) treatment effects. Futility analyses were applied after 25, 50 and 75% of events were observed, or patients were recruited. Outcomes were conditional power (CP), and time and cost savings. Results: Futility analyses could stop some trials with no benefit, but not all. After observing 50% of the target number of events, 3 out of 5 trials with no benefit could be stopped early (low CPless than or equal to15%). Trial duration for two studies could be reduced by 4–24 months, saving £44 000–231 000, but the third had already stopped recruiting, hence no savings were made. However, of concern was that 2 of the 4 trials with moderate treatment effects could be stopped early at some point, although they eventually showed worthwhile benefits. Conclusions: Careful application of futility can lead to future patients in a trial not being given an ineffective treatment, and should therefore be used more often. A secondary consideration is that it could shorten trial duration and reduce costs. However, studies with modest treatment effects could be inappropriately stopped early. Unless there is very good evidence for futility, it is often best to continue to the planned end

The design, launch and assessment of a new volunteer-based plant monitoring scheme for the United Kingdom

Volunteer-based plant monitoring in the UK has focused mainly on distribution mapping; there has been less emphasis on the collection of data on plant communities and habitats. Abundance data provide different insights into ecological pattern and allow for more powerful inference when considering environmental change. Abundance monitoring for other groups of organisms is well-established in the UK, e.g. for birds and butterflies, and conservation agencies have long desired comparable schemes for plants. We describe a new citizen science scheme for the UK (the ‘National Plant Monitoring Scheme’; NPMS), with the primary aim of monitoring the abundance of plants at small scales. Scheme development emphasised volunteer flexibility through scheme co-creation and feedback, whilst retaining a rigorous approach to design. Sampling frameworks, target habitats and species, field methods and power are all described. We also evaluate several outcomes of the scheme design process, including: (i) landscape-context bias in the first two years of the scheme; (ii) the ability of different sets of indicator species to capture the main ecological gradients of UK vegetation; and, (iii) species richness bias in returns relative to a professional survey. Survey rates have been promising (over 60% of squares released have been surveyed), although upland squares are under-represented. Ecological gradients present in an ordination of an independent, unbiased, national survey were well-represented by NPMS indicator species, although further filtering to an entry-level set of easily identifiable species degraded signal in an ordination axis representing succession and disturbance. Comparison with another professional survey indicated that different biases might be present at different levels of participation within the scheme. Understanding the strengths and limitations of the NPMS will guide development, increase trust in outputs, and direct efforts for maintaining volunteer interest, as well as providing a set of ideas for other countries to experiment with

Design and testing of a national pollinator and pollination monitoring framework

Final summary report to the Department for Environment, Food and Rural Affairs (Defra), Scottish Government and Welsh Government: Project WC1101

Pollinator monitoring more than pays for itself

1. Resilient pollination services depend on sufficient abundance of pollinating insects over time. Currently, however, most knowledge about the status and trends of pollinators is based on changes in pollinator species richness and distribution only. 2. Systematic, long‐term monitoring of pollinators is urgently needed to provide baseline information on their status, to identify the drivers of declines and to inform suitable response measures. 3. Power analysis was used to determine the number of sites required to detect a 30% change in pollinator populations over 10 years. We then evaluated the full economic costs of implementing four national monitoring schemes in the UK: (a) professional pollinator monitoring, (b) professional pollination service monitoring, (c) volunteer collected pan traps and (d) volunteer focal floral observations. These costs were compared to (a) the costs of implementing separate, expert‐designed research and monitoring networks and (b) the economic benefits of pollination services threatened by pollinator loss. 4. Estimated scheme costs ranged from £6,159/year for a 75‐site volunteer focal flower observation scheme to £2.7 M/year for an 800‐site professional pollination service monitoring network. The estimated research costs saved using the site network as research infrastructure range from £1.46–4.17 M/year. The economic value of UK crop yield lost following a 30% decline in pollinators was estimated at ~£188 M/year. 5. Synthesis and applications. We evaluated the full costs of running pollinator monitoring schemes against the economic benefits to research and society they provide. The annual costs of monitoring are <0.02% of the economic value of pollination services that would be lost after a 30% decline in pollination services. Furthermore, by providing high‐quality scientific data, monitoring schemes would save at least £1.5 on data collection per £1 spent. Our findings demonstrate that long‐term systematic monitoring can be a cost‐effective tool for both answering key research questions and setting action points for policymakers. Careful consideration must be given to scheme design, the logistics of national‐scale implementation and resulting data quality when selecting the most appropriate combination of surveyors, methods and site networks to deliver a successful scheme

Socio-demographic variations in moves to institutional care 1991-2001: a record linkage study from England and Wales.

BACKGROUND: Only a minority of older people in England and Wales live in institutional care, but among the older of the old, this minority is large. Disability is the major driver of admissions, but socio-demographic factors are also relevant. Understanding more about the influence of these is important for planning by long-term care. OBJECTIVE: To investigate effects of socio-demographic factors, including housing tenure, household type, marital status, and number of children, on the proportions of elderly people who made a transition from living in the community in 1991 to living in institutional care in 2001. SUBJECTS AND SETTING: Nationally representative record linkage study including 36,650 people aged 65 years and over, living in the community in England and Wales in 1991, who were still alive in 2001. Nineteen thousand women aged 75-89 years in 2001 were included in additional analyses of effects of parity (number of children borne). METHODS: Bi-variate and multivariate analyses of variations in sample proportions, who by 2001 were resident in institutional care. RESULTS: 4.3% of men and 9.3% of women in the surviving sample then aged 75 years and over, were in institutional care in 2001. Older age, living in rented accommodation, living alone in 1991 and being unmarried in 2001, as well as long-term illness, were associated with higher proportions making this transition. Women had higher risks than men. Childless women aged 64-79 years in 1991 had a 25% higher risk than women with children of being in institutional care in 2001. CONCLUSION: Socio-demographic factors continue to influence risks of entry to institutional care in England and Wales

Should biopsy influence tumour staging in Wilms tumour? The UK experience [Abstract]

Purpose: On behalf of the Renal Tumours Committee, Children’s Cancer and Leukaemia Group,CCLG. The influence of percutaneous biopsy on local recurrence rates ofWilms tumour (WT) in the setting of pre-operative chemotherapy followed by delayed nephrectomy has not been systematically reported. The UKW3 trial compared biopsy/pre-operative chemotherapy and immediate nephrectomy and affords the opportunity to examine this question.Method: Data on treatment and outcome for 647 patients with unilateral WT (stage I-IV) registered in the UKW3 trial (1991–2001) were analysed. Metastatic and ‘inoperable’ tumours were electively biopsied, 39% of localised tumours were randomised; overall, 299 had biopsy and 348 immediate nephrectomy. Patients with metachronous relapse or early progressive disease were excluded. Hazard ratios (HR) for risk of abdominal recurrence (excluding liver metastases) were calculated by Cox regression analysis. Adjustments included tumour histology (605FH, 42UH), stage, age, largest tumour size in one dimension and lymph node metastasis. Results: 50/647 (7.7%) patients experienced a relapse involving the abdomen (þ/-distant) and 63 distant relapse only. Anaplastic histology, positive lymph nodes, stage IV disease and increasing tumour size were all significantly associated with increased risk of any recurrence. Only anaplastic histology and increasing tumour size were significantly associated with abdominal recurrence. The adjusted HRs for association of biopsy with abdominal recurrence (HR:1.75 (95%CI:0.91–3.38, p¼0.10) or any relapse/death (HR:1.42 (95%CI:0.94–2.15, p¼0.10) did not reach statistical significance. Conclusion: The UKW3 trial provides reassurance that biopsy should not automatically lead to ‘upstaging’ of WT but that treatment intensity can be based on tumour stage at delayed nephrectomy. Note that biopsy was helpful in revealing non- WT in 12% of cases in this trial (Vujanic et al, MPO 2003). International comparison of local recurrence rates in the ongoing SIOP WT 2001 trial, where the UK continues to use biopsy without influencing tumour stage, will provide a further assessment of this ongoing controversial area

Prognostic factors for recurrence and survival in anal cancer

BACKGROUND: Only 2 prospective studies have previously reported prognostic factors for anal cancer, European Organization for Research and Treatment of Cancer trial 22861 (EORTC 22861) and Radiation Therapy Oncology Group trial 98-11 (RTOG 98-11). Both of those trials reported that clinically positive lymph nodes and male sex predicted poorer overall survival (OS). The EORTC 22861 trial indicated that the same factors were prognostic for locoregional control. In the current report, the authors investigated potential prognostic factors from the first United Kingdom Coordinating Committee on Cancer Research Anal Cancer Trial (ACT I), in which patients were randomized to receive either radiotherapy alone or chemoradiation (CRT) with concurrent 5-fluorouracil/mitomycin C. METHODS: In the ACT I trial, associations between several baseline characteristics and 3 endpoints were investigated: locoregional failure (LRF), anal cancer death (ACD), and OS. The analyses were restricted to 292 patients who received CRT, which subsequently became standard treatment. A score was derived using multivariable Cox regression to identify the set of factors that, together, had the best prognostic performance. This score was then validated with a large, independent prospective trial (the ACT II trial). RESULTS: Palpable, clinically positive lymph nodes were associated with LRF (P = .012), a greater risk of ACD (P = .031), and decreased OS (P = .006) in multivariable analyses. Men had worse outcomes than women for LRF (P = .036), ACD (P = .039), and OS (P = .008). On average, a lower hemoglobin level had an adverse effect on ACD (P = .008), and a higher white blood cell count had an adverse effect on OS (P = .001). However, external validation of the score was poor for LRF (area under the curve [AUC] = 54%) but was better for ACD (AUC = 67%) and OS (AUC = 63%). CONCLUSIONS: The results from this analysis of the ACT I trial supported evidence for palpable lymph nodes and male sex as prognostic factors for LRF and OS, and lower hemoglobin levels and a higher white blood cell count were identified as prognostic factors for ACD and OS, respectively. Cancer 2013. © 2012 American Cancer Society

Assessment of the water quality outcomes from Agri-Environment & development of an associated Rural Development Programme (RDP) ‘impact’ indicator for Agriculture & Water Quality. Environmental Stewardship monitoring and evaluation framework request for mini-tender

The aim of this project is to meet the urgent need for further understanding of (1) the effectiveness of agri-environment scheme delivery on ecological and chemical water quality and (2) the monitoring programme required to enable its quantification