Search

IntroductionGiven the risks inherent in care transitions, it is imperative that patients discharged from hospital to home receive the integrated care services necessary to ensure a successful transition. Despite efforts by the healthcare sector to develop health system solutions to improve transitions, problems persist. Research on transitional support has predominantly focused on services delivered by healthcare professionals; the evidence for services provided by lay navigators or volunteers in this context has not been synthesised. This scoping review will map the available literature on the engagement of volunteers within third sector organisations supporting adults in the transition from hospital to home.Methods and analysisUsing the well-established scoping review methodology outlined by the Joanna Briggs Institute, a five-stage review is outlined: (1) determining the research question, (2) search strategy, (3) inclusion criteria, (4) data extraction and (5) analysis and presentation of the results. The search strategy will be applied to 10 databases reflecting empirical and grey literature. A two-stage screening process will be used to determine eligibility of articles. To be included in the review, articles must describe a community-based programme delivered by a third sector organisation that engages volunteers in the provisions of services that support adults transitioning from hospital to home. All articles will be independently assessed for eligibility, and data from eligible articles will be extracted and charted using a standardised form. Extracted data will be analysed using narrative and descriptive analyses.Ethics and disseminationEthics approval is not required for this scoping review. Members of an international special interest group focused on the voluntary sector will be consulted to provide insight and feedback on study findings, help with dissemination of the results and engage in the development of future research proposals. Dissemination activities will include peer-reviewed publications and academic presentations.

BackgroundGiven the risks inherent in care transitions, it is imperative that patients discharged from hospital to home receive the integrated care services necessary to ensure that the transition is successful. Despite efforts by the health care sector to develop health system solutions to improve transitions, problems persist. Research on transitional support has predominantly focused on services delivered by health care professionals; the evidence for services provided by lay navigators or volunteers in supporting people transitioning from hospital to home has not been synthesized to guide practice, policy or future research.AimThis is a protocol for a scoping review that will examine the role and contributions of voluntary sector personnel and services to support transitions from hospital to home.MethodsUsing the well-established scoping review methodology outlined by Arksey and O’Malley, a six-stage study is outlined (1) identifying the research question, (2) identifying relevant studies, (3) selecting studies, (4) charting the data, (5) collating, summarizing and reporting the results, and (6) providing consultation. The search strategy, designed by an information scientist, is applied to ten databases reflecting empirical and grey literature sources. A two-stage screening process will be used to determine eligibility of articles. To be included in the review, articles must report on a community-based program that engages volunteers in the provisions of services that support adults transitioning from hospital to home. All articles will be independently assessed for eligibility, and data from eligible articles will be abstracted and charted using a standardized form. Extracted data will be analyzed using narrative and descriptive analyses. Research ethics approval is not required for this scoping review.DiscussionThis scoping review will map the available literature focused on the contributions of voluntary sector personnel and services to support transitions from hospital to home.

This review summarizes the evidence from six randomized controlled trials that judged the effectiveness of systematic review summaries on policymakers' decision making, or the most effective ways to present evidence summaries to increase policymakers' use of the evidence. This review included six randomized controlled studies. A randomized controlled study is one in which the participants are divided randomly (by chance) into separate groups to compare different treatments or other interventions. This method of dividing people into groups means that the groups will be similar and that the effects of the treatments they receive will be compared more fairly. At the time the study is done, it is not known which treatment is the better one. The researchers who did these studies invited people from Europe, North America, South America, Africa, and Asia to take part in them. Two studies looked at “policy briefs,” one study looked at an “evidence summary,” two looked at a “summary of findings table,” and one compared a “summary of findings table” to an evidence summary. None of these studies looked at how policymakers directly used evidence from systematic reviews in their decision making, but two studies found that there was little to no difference in how they used the summaries. The studies relied on reports from decision makers. These studies included questions such as, “Is this summary easy to understand?” Some of the studies looked at users' knowledge, understanding, beliefs, or how credible (trustworthy) they believed the summaries to be. There was little to no difference in the studies that looked at these outcomes. Study participants rated the graded entry format higher for usability than the full systematic review. The graded entry format allows the reader to select how much information they want to read. The study participants felt that all evidence summary formats were easier to understand than full systematic reviews. Plain language summary Policy briefs make systematic reviews easier to understand but little evidence of impact on use of study findings It is likely that evidence summaries are easier to understand than complete systematic reviews. Whether these summaries increase the use of evidence from systematic reviews in policymaking is not clear. What is this review about? Systematic reviews are long and technical documents that may be hard for policymakers to use when making decisions. Evidence summaries are short documents that describe research findings in systematic reviews. These summaries may simplify the use of systematic reviews. Other names for evidence reviews are policy briefs, evidence briefs, summaries of findings, or plain language summaries. The goal of this review was to learn whether evidence summaries help policymakers use evidence from systematic reviews. This review also aimed to identify the best ways to present the evidence summary to increase the use of evidence. What is the aim of this review? This review summarizes the evidence from six randomized controlled trials that judged the effectiveness of systematic review summaries on policymakers' decision making, or the most effective ways to present evidence summaries to increase policymakers' use of the evidence. What are the main findings of this review? This review included six randomized controlled studies. A randomized controlled study is one in which the participants are divided randomly (by chance) into separate groups to compare different treatments or other interventions. This method of dividing people into groups means that the groups will be similar and that the effects of the treatments they receive will be compared more fairly. At the time the study is done, it is not known which treatment is the better one. The researchers who did these studies invited people from Europe, North America, South America, Africa, and Asia to take part in them. Two studies looked at “policy briefs,” one study looked at an “evidence summary,” two looked at a “summary of findings table,” and one compared a “summary of findings table” to an evidence summary. None of these studies looked at how policymakers directly used evidence from systematic reviews in their decision making, but two studies found that there was little to no difference in how they used the summaries. The studies relied on reports from decision makers. These studies included questions such as, “Is this summary easy to understand?” Some of the studies looked at users' knowledge, understanding, beliefs, or how credible (trustworthy) they believed the summaries to be. There was little to no difference in the studies that looked at these outcomes. Study participants rated the graded entry format higher for usability than the full systematic review. The graded entry format allows the reader to select how much information they want to read.. The study participants felt that all evidence summary formats were easier to understand than full systematic reviews. What do the findings of this review mean? Our review suggests that evidence summaries help policymakers to better understand the findings presented in systematic reviews. In short, evidence summaries should be developed to make it easier for policymakers to understand the evidence presented in systematic reviews. However, right now there is very little evidence on the best way to present systematic review evidence to policymakers. How up to date is this review? The authors of this review searched for studies through June 2016. Executive summary/Abstract Background Systematic reviews are important for decision makers. They offer many potential benefits but are often written in technical language, are too long, and do not contain contextual details which makes them hard to use for decision‐making. Strategies to promote the use of evidence to decision makers are required, and evidence summaries have been suggested as a facilitator. Evidence summaries include policy briefs, briefing papers, briefing notes, evidence briefs, abstracts, summary of findings tables, and plain language summaries. There are many organizations developing and disseminating systematic review evidence summaries for different populations or subsets of decision makers. However, evidence on the usefulness and effectiveness of systematic review summaries is lacking. We present an overview of the available evidence on systematic review evidence summaries. Objectives This systematic review aimed to 1) assess the effectiveness of evidence summaries on policy‐makers' use of the evidence and 2) identify the most effective summary components for increasing policy‐makers' use of the evidence. Search methods We searched several online databases (Medline, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, Global Health Library, Popline, Africa‐wide, Public Affairs Information Services, Worldwide Political Science Abstracts, Web of Science, and DfiD), websites of research groups and organizations which produce evidence summaries, and reference lists of included summaries and related systematic reviews. These databases were searched in March‐April, 2016. Selection criteria Eligible studies included randomised controlled trials (RCTs), non‐randomised controlled trials (NRCTs), controlled before‐after (CBA) studies, and interrupted time series (ITS) studies. We included studies of policymakers at all levels as well as health system managers. We included studies examining any type of “evidence summary”, “policy brief”, or other product derived from systematic reviews that presented evidence in a summarized form. These interventions could be compared to active comparators (e.g. other summary formats) or no intervention. The primary outcomes were: 1) use of systematic review summaries decision‐making (e.g. self‐reported use of the evidence in policy‐making, decision‐making) and 2) policymaker understanding, knowledge, and/or beliefs (e.g. changes in knowledge scores about the topic included in the summary). We also assessed perceived relevance, credibility, usefulness, understandability, and desirability (e.g. format) of the summaries. Results Our database search combined with our grey literature search yielded 10,113 references after removal of duplicates. From these, 54 were reviewed in full text and we included 6 studies (reported in 7 papers, 1661 participants) as well as protocols from 2 ongoing studies. Two studies assessed the use of evidence summaries in decision‐making and found little to no difference in effect. There was also little to no difference in effect for knowledge, understanding or beliefs (4 studies) and perceived usefulness or usability (3 studies). Summary of Findings tables and graded entry summaries were perceived as slightly easier to understand compared to complete systematic reviews. Two studies assessed formatting changes and found that for Summary of Findings tables, certain elements, such as reporting study event rates and absolute differences were preferred as well as avoiding the use of footnotes. No studies assessed adverse effects. The risks of bias in these studies were mainly assessed as unclear or low however, two studies were assessed as high risk of bias for incomplete outcome data due to very high rates of attrition. Authors' conclusions Evidence summaries may be easier to understand than complete systematic reviews. However, their ability to increase the use of systematic review evidence in policymaking is unclear.

ContextOpioid related deaths are at epidemic levels in many developed nations globally. Concerns about the contribution of prescribed opioids, and particularly high-dose opioids, continue to mount as do initiatives to reduce prescribing. Evidence around opioid tapering, which can be challenging and potentially hazardous, is not well developed. A recent national guideline has recognized this and recommended referral to multidisciplinary care for challenging cases of opioid tapering. However, multidisciplinary care for opioid tapering is not well understood or defined.ObjectiveIdentify the existing literature on any multidisciplinary care programs that evaluate impact on opioid use, synthesize how these programs work and clarify whom they benefit.Study designSystematic rapid realist review.DatasetBibliographic databases (MEDLINE, EMBASE, CINAHL, PsycINFO, Cochrane Library), grey literature, reference hand search and formal expert consultation.Results95 studies were identified. 75% of the programs were from the United States and the majority (n = 62) were published after 2000. A minority (n = 23) of programs reported on >12 month opioid use outcomes. There were three necessary but insufficient mechanisms common to all programs: pain relief, behavior change and active medication management. Programs that did not include a combination of all three mechanisms did not result in opioid dose reductions. A concerning 20-40% of subjects resumed opioid use within one year of program completion.ConclusionsProviding alternative analgesia is insufficient for reducing opioid doses. Even high quality primary care multidisciplinary care programs do not reduce prescribed opioid use unless there is active medication management accomplished by changing the primary opioid prescriber. Rates of return to use of opioids from these programs are very concerning in the current context of a highly potent and lethal street drug supply. This contextual factor may be powerful enough to undermine the modest benefits of opioid dose reduction via multidisciplinary care.

IntroductionOlder adults may experience challenges during the hospital to home transitions that could be mitigated by digital health solutions. However, to promote adoption in practice and realise benefits, there is a need to specify how digital health solutions contribute to hospital to home transitions, particularly pertinent in this era of social distancing. This rapid review will: (1) elucidate the various roles and functions that have been developed to support hospital to home transitions of care, (2) identify existing digital health solutions that support hospital to home transitions of care, (3) identify gaps and new opportunities where digital health solutions can support these roles and functions and (4) create recommendations that will inform the design and structure of future digital health interventions that support hospital to home transitions for older adults (eg, the pre-trial results of the Digital Bridge intervention; ClinicalTrials.gov Identifier:NCT04287192).Methods and analysisA two-phase rapid review will be conducted to meet identified aims. In phase 1, a selective literature review will be used to generate a conceptual map of the roles and functions of individuals that support hospital to home transitions for older adults. In phase 2, a search on MEDLINE, EMBASE and CINAHL will identify literature on digital health solutions that support hospital to home transitions. The ways in which digital health solutions can support the roles and functions that facilitate these transitions will then be mapped in the analysis and generation of findings.Ethics and disseminationThis protocol is a review of the literature and does not involve human subjects, and therefore, does not require ethics approval. This review will permit the identification of gaps and new opportunities for digital processes and platforms that enable care transitions and can help inform the design and implementation of future digital health interventions. Review findings will be disseminated through publications and presentations to key stakeholders.

Background Systematic reviews are important for decision makers. They offer many potential benefits but are often written in technical language, are too long, and do not contain contextual details which make them hard to use for decision-making. There are many organizations that develop and disseminate derivative products, such as evidence summaries, from systematic reviews for different populations or subsets of decision makers. This systematic review aimed to (1) assess the effectiveness of evidence summaries on policymakers’ use of the evidence and (2) identify the most effective summary components for increasing policymakers’ use of the evidence. We present an overview of the available evidence on systematic review derivative products. Methods We included studies of policymakers at all levels as well as health system managers. We included studies examining any type of “evidence summary,” “policy brief,” or other products derived from systematic reviews that presented evidence in a summarized form. The primary outcomes were the (1) use of systematic review summaries in decision-making (e.g., self-reported use of the evidence in policymaking and decision-making) and (2) policymakers’ understanding, knowledge, and/or beliefs (e.g., changes in knowledge scores about the topic included in the summary). We also assessed perceived relevance, credibility, usefulness, understandability, and desirability (e.g., format) of the summaries. Results Our database search combined with our gray literature search yielded 10,113 references after removal of duplicates. From these, 54 were reviewed in full text, and we included six studies (reported in seven papers) as well as protocols from two ongoing studies. Two studies assessed the use of evidence summaries in decision-making and found little to no difference in effect. There was also little to no difference in effect for knowledge, understanding or beliefs (four studies), and perceived usefulness or usability (three studies). Summary of findings tables and graded entry summaries were perceived as slightly easier to understand compared to complete systematic reviews. Two studies assessed formatting changes and found that for summary of findings tables, certain elements, such as reporting study event rates and absolute differences, were preferred as well as avoiding the use of footnotes. Conclusions Evidence summaries are likely easier to understand than complete systematic reviews. However, their ability to increase the use of systematic review evidence in policymaking is unclear. Trial registration The protocol was published in the journal Systematic Reviews (2015;4:122) Electronic supplementary material The online version of this article (doi:10.1186/s13012-016-0530-3) contains supplementary material, which is available to authorized users.

New U–Th–Ra, major and trace element, and Sr–Nd–Pb isotope data are presented for young lavas from the New Britain and Western Bismarck arcs in Papua New Guinea. New Britain is an oceanic arc, whereas the latter is the site of an arc–continent collision. Building on a recent study of the Manus Basin, contrasts between the two arcs are used to evaluate the processes and timescales of magma generation accompanying arc–continent collision and possible slab detachment. All three suites share many attributes characteristic of arc lavas that can be ascribed to the addition of a regionally uniform subduction component derived from the subducting altered oceanic crust and sediment followed by dynamic melting of the modified mantle. However, the Western Bismarck arc lavas diverge from the Pb isotope mixing array formed by the New Britain and the Manus Basin lavas toward elevated 208Pb/204Pb. We interpret this to reflect a second and subsequent addition of sediment melt at crustal depth during collision. 238U and 226Ra excesses are preserved in all of the lavas and are greatest in the Western Bismarck arc. High-Mg andesites with high Sr/Y ratios in the westernmost arc are attributed to recent shallow mantle flux melting at the slab edge. Data for two historical rhyolites are also presented. Although these rhyolites formed in quite different tectonic settings and display different geochemical and isotopic compositions, both formed from mafic parents within millennia.

Intra-caldera eruptions have been speculated to sample the last batches of magma remaining from earlier caldera-forming eruptions. Rabaul Caldera, New Britain, Papua New Guinea has erupted several times since the last caldera-forming eruption in AD 640, with the most recent intra-caldera eruptions in 1878, 1937^1941 and 1994^ present from the Tavurvur and Vulcan vents. U-series isotopes, in conjunction with Sr/Sr and Nd/Nd, were analyzed on 16 samples collected from 1994 to 2001 to monitor short-term changes in magma composition to model magmatic processes and to test whether there is evidence of recent fresh magma input. Inflections on MgO diagrams imply that fractional crystallization is an important process in long-term magma evolution, and the homogeneity in Sr/Sr and Nd/Nd shows that assimilation of isotopically distinct material has not occurred. A vertical array on a Th^U isochron diagram requires open-system behavior and could support a model of differentiation of multiple magma batches over 26 kyr. However, the presence of (Ra/Th) excesses requires introduction of new magma within the past 8000 years and is permissible of a model in which the currently erupting magmas were emplaced at or since the last caldera-forming event. Other than the presence of mafic enclaves in the 1878 and 1937 eruptions, no evidence exists to suggest open-system magma injection. Systematic variation in U-series disequilibria between 1994 and 2001 is lacking, which may indicate that the system is broadly in steady state or that the processes acting to produce the limited compositional variation have time scales that are too short to be resolved by Ra isotopes (i.e. are less than a few hundred years).

We report antemortem pathologic and neuroimaging findings of severe myelotoxicity from intrathecal chemotherapy in a case of blastic plasmacytoid dendritic cell neoplasm (BPDCN) complicated by leptomeningeal disease. A 73 year old male was diagnosed with BPDCN after fine needle aspiration of an enlarged cervical lymph node. Total body PET imaging revealed extensive systemic hypermetabolic lymphadenopathy and a staging lumbar puncture was positive for malignant cells. He was treated with etoposide, vincristine, doxorubicin, cyclophosphamide, prednisone (EPOCH) and five doses of intrathecal cytosine arabinoside with the last dose administered on 2 months after diagnosis with CSF clearing. One year later, he developed progressive lower extremity weakness, numbness and bowel/bladder dysfunction. Lumbar spine imaging 4 weeks later revealed subtle linear enhancement along the cauda equina and within the dependent thecal sac, but cervical and thoracic spine MRI at this time were unremarkable. CSF showed atypical lymphoid cells and an Ommaya reservoir was placed. Intrathecal chemotherapy with methotrexate and cytarabine was started. Subsequent CSF analysis showed no malignant cells. However, the patient continued to have progressive ascending weakness and numbness, and his neurologic condition progressed to tetraplegia, low of bowel and bladder control and severe sensory loss, especially to vibration and joint position modalities. Spine MRI showed high signal intensity involving the posterior columns diffusely in the cervico-thoracic spinal cord. Metabolic and infectious work up was negative. A subsequent biopsy of the posterior columns of the lower thoracic spinal cord demonstrated cord destruction with profuse macrophage infiltration without evidence of malignant cells or microorganisms. Treatment with folate and cyanocobalamin resulted in no improvement, and the patient elected for palliative care only. This case illustrates central nervous system involvement by a rare myeloid tumor and demonstrates neuroimaging and unique antemortem pathology of intrathecal chemotherapy-induced myelotoxicity.

Targeted agents against brain tumors bearing specific pathway activation are postulated to provide significant responses but the utility of this approach has not been consistently shown. We report the use of such targeted therapy in two patients with rare tumors who demonstrated exceptional responses. The first was a 36 year old female who had a temporal dural based tumor with features of an atypical meningioma but with GFAP expression and brain invasion raising the possibility of a dural invasive glial malignancy. After two resections and radiation therapy, the patient rapidly deteriorated due to aggressive recurrence with extensive pan-neuraxis leptomeningeal disease causing quadriparesis, encephalopathy and status epilepticus needing ventilator support and consideration of hospice care. Based on detection of BRAFv600E mutation in the tumor, an IRB approved compassionate IND application for an investigational liquid formulation of dabrafenib was filed with the FDA and treatment initiated. The patient responded to dabrafenib with radiological improvement and respiratory recovery, normalization of mental status, resolution of seizures and recovery of normal strength in her upper extremities but with persistent paraplegia. The improvement remained durable for several months but was compromised by treatment-independent neurologic complications. The second patient was a 68 year old female with a right sphenoid wing skull base mass causing VII and VIII nerve palsies, which on resection was consistent with a perivascular epithelioid cell tumor (PEComa). FDG-PET scan-based staging showed extensive asymptomatic hypermetabolic malignancy including a left ovarian mass, a large retroperitoneal mass, and multiple liver and lung metastases. Given that PEComas often demonstrate mTOR pathway activation, the patient was treated with everolimus. Subsequent PET scan showed significant reduction in size and activity of the systemic lesions. These cases illustrate the utility of rationally selected molecular targeted therapy against rare brain neoplasms that can potentially yield exceptional responses.

Introduction An increasing number of people are living longer with multiple health and social care needs, and may rely heavily on health system resources. When dealing with multiple conditions, patients, caregivers and healthcare providers (HCPs) often experience high treatment burden due to unclear care trajectories, a myriad of treatment decisions and few guidelines on how to manage care needs. By understanding patient and caregiver priorities, and setting treatment goals, HCPs may help improve patient outcomes and experiences. This study aims to examine the extent and nature of the literature on treatment goal setting in complex patients, identify gaps in evidence and areas for further inquiry and guide a research programme to develop definitions, measures and recommendations for treatment goal setting. Methods and analysis This study protocol outlines a scoping review of the peer reviewed and the grey literature, using established scoping review methodology. Literature will be identified using a multidatabase and grey literature search strategy developed by two librarians. Papers and reports on the topic of goal setting that address complexity or complex patients will be included. Results of the search will be screened independently by two reviewers and included studies will be abstracted and charted in duplicate. Ethics and dissemination Ethics approval is not required for this scoping review. Working with the knowledge users on the team, we will prepare educational materials and presentations to disseminate study findings to HCPs, caregivers and patients, and at relevant national and international conferences. Results will also be published in a peer-reviewed journal.

Background Preventative medicine has become increasingly important in efforts to reduce the burden of chronic disease in industrialised countries. However, interventions that fail to recruit socio-economically representative samples may widen existing health inequalities. This paper explores the barriers and facilitators to engaging a socio-economically disadvantaged (SED) population in primary prevention for coronary heart disease (CHD). Methods The primary prevention element of Have a Heart Paisley (HaHP) offered risk screening to all eligible individuals. The programme employed two approaches to engaging with the community: a) a social marketing campaign and b) a community development project adopting primarily face-to-face canvassing. Individuals living in areas of SED were under-recruited via the social marketing approach, but successfully recruited via face-to-face canvassing. This paper reports on focus group discussions with participants, exploring their perceptions about and experiences of both approaches. Results Various reasons were identified for low uptake of risk screening amongst individuals living in areas of high SED in response to the social marketing campaign and a number of ways in which the face-to-face canvassing approach overcame these barriers were identified. These have been categorised into four main themes: (1) processes of engagement; (2) issues of understanding; (3) design of the screening service and (4) the priority accorded to screening. The most immediate barriers to recruitment were the invitation letter, which often failed to reach its target, and the general distrust of postal correspondence. In contrast, participants were positive about the face-to-face canvassing approach. Participants expressed a lack of knowledge and understanding about CHD and their risk of developing it and felt there was a lack of clarity in the information provided in the mailing in terms of the process and value of screening. In contrast, direct face-to-face contact meant that outreach workers could explain what to expect. Participants felt that the procedure for uptake of screening was demanding and inflexible, but that the drop-in sessions employed by the community development project had a major impact on recruitment and retention. Conclusion Socio-economically disadvantaged individuals can be hard-to-reach; engagement requires strategies tailored to the needs of the target population rather than a population-wide approach.

On White Island, New Zealand, the intensified period of strombolian-volcanian and phreatomagmatic explosive activity that commenced in March 1977 led to eruption of unusually primitive, high-Mg andesites. These are Fo80-93 olivine-saturated rocks that have MgO contents up to 10% (Mg# = 65-71) and SiO2 of 56-58%. They have incompatible trace element characteristics that are typical of arc rocks. 87Sr/86Sr, 143Nd/144Nd and 176Hf/177Hf ratios (0.7049-0.7053, 0.51282-0.51266 and 0.28301-0.28298, respectively) are consistent with subducted sediment addition and/or crustal input but there is no clear correlation of either isotope ratio with MgO. The rocks have modest (3-10%) 238U excesses at low (230Th/232Th) ratios (0.697 to 0.722). 226Ra-230Th disequilibria are also restricted but, unusually, include both 226Ra excesses and deficits with (226Ra/230Th) = 0.94-1.07. (210Pb/226Ra)o ranges from 0.98 to 1.52 requiring gas accumulation that may increase over time and with decreasing MgO. Sr/Y and Tb/Yb ratios are both low and relatively invariant at 8 and 0.3, respectively, and along with the 238U excesses preclude an origin in which residual garnet was involved. The occurrence of some 226Ra deficits suggests the presence of residual amphibole during partial melting for some samples. Rapid magma ascent (to preserve the 226Ra disequilibria) limits the amount of possible melt-wall rock interaction that might reduce source-derived Tb/Yb ratios and in the mantle or raise 87Sr/86Sr in the crust. The White Island high-Mg andesites did not form by partial melting of eclogite in the subducting Pacific plate. Their primitive, olivine-saturated compositions suggest that their source was peridotitic and experimental data suggest that equilibration with peridotite at low temperatures at 0.5-1.5 GPa and in the presence of elevated alkalis can reconcile the high SiO2 and MgO of the rocks. This may reflect stalling of the magmas beneath the continental lithosphere for a few 1000 years. © 2007 Elsevier B.V. All rights reserved.