Publications by authors named "Christine Ribic"

41 Publications

Diel patterns of predation and fledging at nests of four species of grassland songbirds.

Ecol Evol 2021 Jun 1;11(11):6913-6926. Epub 2021 May 1.

U.S. Geological Survey (emeritus) Northern Prairie Wildlife Research Center Jamestown ND USA.

Although it is common for nestlings to exhibit a strong bias for fledging in the morning, the mechanisms underlying this behavior are not well understood. Avoiding predation risk has been proposed as a likely mechanism by a number of researchers. We used video surveillance records from studies of grassland birds nesting in North Dakota, Minnesota, and Wisconsin to determine the diel pattern of nest predation and fledging patterns of four ground-nesting obligate grassland passerines (Grasshopper Sparrow (), Savannah Sparrow (), Bobolink (), and Eastern Meadowlark ()). We used the nest predation pattern as a surrogate for predation activity to test whether nestlings minimized predation risk by avoiding fledging when predation activity was high and preferentially fledging when predation risk was low. Predation activity was significantly lower starting 3 hr before sunrise and ending 3 hr after sunrise, followed by a transition to a period of significantly higher activity lasting for 4 hr, before declining to an average activity level for the rest of the diel period. There was little evidence that the four grassland bird species avoided fledging during the high-risk period and Savannah Sparrow fledged at higher rates during that period. All four species had hours during the low-risk period where they fledged at higher rates, but only Grasshopper Sparrow fledged preferentially during that period. Bobolink and Eastern Meadowlark had multiple hours with high fledging rates throughout the daytime period, resulting in no relationship between probability of fledging and predation risk. Given the species variability in fledging pattern seen in our study, it is unlikely that there is a universal response to any driver that affects time of fledging. Further study is needed to understand the complex interplay between species ecology and drivers such as physiology, energetics, and predation in affecting grassland bird fledging behavior.
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http://dx.doi.org/10.1002/ece3.7541DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8207369PMC
June 2021

A new approach to the study of relationship quality in dolphins: Framework and preliminary results.

Behav Processes 2020 Dec 2;181:104260. Epub 2020 Oct 2.

Dolphin Communication Project, Port Saint Lucie, FL, United States.

Proximity and synchronous behaviours from surface observations have been used to measure association patterns within and between dolphin dyads. To facilitate an investigation of relationship quality in dolphins, we applied a method used for primates and ravens that examined three main components to describe relationships: value, security, and compatibility. Using pilot data from long-term research of two study populations for this preliminary assessment, these three components were extracted from PCA of eight behavioural variables with more than 80 % variance accounted for in both study groups. Only pair swim position differed between groups. Although value, security, and compatibility are abstract terms, each is based on behaviours identified as important in dolphin social life, at least for these two populations. Examining relationship quality in dolphins with a method used to illustrate dyadic differences for primates and ravens allows for a quantitative, comparative assessment of sociality across disparate taxa. Although these species are diverse in their anatomies and in their social habitats (e.g., aquatic, terrestrial, aerial), they may well share the basic societal building blocks in the factors affecting how relationships are formed. We discuss how an examination of these behavioural variables facilitates understanding relationship quality in dolphins, as well as how dolphin relationships fit into the context of social animals' society.
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http://dx.doi.org/10.1016/j.beproc.2020.104260DOI Listing
December 2020

Incidence of Direct Oral Anticoagulant Prescriptions in Kidney Transplant Recipients in Ontario, Canada.

Transplant Proc 2020 Dec 11;52(10):3144-3152. Epub 2020 May 11.

Division of Nephrology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada; ICES, Toronto, Ontario, Canada; Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada. Electronic address:

Background: Kidney transplant recipients (KTRs) are routinely excluded from direct oral anticoagulant (DOAC) trials. Given the lack of safety and efficacy data in this population, we examined real-world prescribing practices of DOACs in KTRs.

Methods: We conducted a retrospective cohort study using linked administrative data sets in Ontario, Canada. All adult KTRs (n = 5580) from June 23, 2009, to March 31, 2017, were included. The primary outcomes were the first prescription for a DOAC or warfarin. Patients were censored on graft failure, death, or end of follow-up.

Results: The mean age was 55 (SD, 14) years; 63% were male, and 65% had received a deceased donor kidney. Over a median follow-up of 5.5 and 4.7 years, 224 KTRs (4.0%) and 824 KTRs (14.8%) were prescribed DOACs and warfarin, respectively. The rates of DOAC and warfarin prescriptions were 8.1 and 32.6 per 1000 person-years, respectively. Older age, receipt of a kidney transplant in more recent years, and higher baseline estimated glomerular filtration rate were associated with DOAC prescription compared with warfarin. Patients with multiple comorbidities and a history of deep venous thromboembolism had a lower risk of DOAC prescription compared with warfarin. When examined by era, the incidence rate of both DOAC and warfarin prescriptions increased significantly over time.

Conclusions: Despite limited safety and efficacy data, DOACs are prescribed to KTRs. However, warfarin still remains more commonly prescribed in this selected patient population. Anticoagulant prescriptions overall are on the rise in KTRs. Further study is needed to determine the safety and efficacy of DOACs in KTRs.
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http://dx.doi.org/10.1016/j.transproceed.2020.02.171DOI Listing
December 2020

Clinical Characteristics and Outcome of Canadian Patients Diagnosed With Atypical Hemolytic Uremic Syndrome.

Can J Kidney Health Dis 2020 24;7:2054358119897229. Epub 2020 Jan 24.

Hôtel-Dieu de Québec, Quebec, QC, Canada.

Background: Atypical hemolytic uremic syndrome (aHUS) is an extremely rare, heterogeneous disease of uncontrolled activation of the alternative complement pathway that is difficult to diagnose. We have evaluated the Canadian patients enrolled in the Global aHUS Registry to provide a Canadian perspective regarding the diagnosis and management of aHUS and the specific challenges faced.

Objective: To evaluate Canadian patients enrolled in the Global aHUS Registry to provide a Canadian perspective regarding the diagnosis and management of aHUS and the specific challenges faced.

Methods: The Global aHUS Registry is an observational, noninterventional, multicenter study that has prospectively and retrospectively collected data from patients of all ages with an investigator-made clinical diagnosis of aHUS, irrespective of treatment. Patients of all ages with a clinical diagnosis of aHUS were eligible and invited for enrollment, and those with evidence of Shiga toxin-producing infection, or with activity ≤10%, or a subsequent diagnosis of thrombotic thrombocytopenic purpura were excluded. Data were collected at enrollment and every 6 months thereafter and were analyzed descriptively for categorical and continuous variables. End-stage renal disease (ESRD)-free survival was evaluated using Kaplan-Meier estimates, and ESRD-associated risk factors of interest were assessed using Cox proportional hazards regression models. Patients were censored at start of eculizumab for any outcome measures.

Results: A total of 37 Canadian patients were enrolled (15 pediatric and 22 adult patients) between February 2014 and May 2017; the median age at initial aHUS presentation was 25.9 (interquartile range = 6.7-51.7) years; 62.2% were female and 94.6% had no family history of aHUS. Over three-quarters of patients (78.4%) had no conclusive genetic or anti-complement factor H (CFH) antibody information available, and most patients (94%) had no reported precipitating factors prior to aHUS diagnosis. Nine patients (8 adults and 1 child) experienced ESRD prior to the study. After initial presentation, there appears to be a trend that children are less likely to experience ESRD than adults, with 5-year ESRD-free survival of 93 and 56% ( = .05) in children and adults, respectively. Enrolling physicians reported renal manifestations in all patients at initial presentation, and 68.4% of patients during the chronic phase (study entry ≥6 months after initial presentation). Likewise, extrarenal manifestations also occurred in more patients during the initial presenting phase than the chronic phase, particularly for gastrointestinal (61.1% vs 15.8%) and central nervous system sites (38.9% vs 5.3%). Fewer children than adults experienced gastrointestinal manifestations (50.0% vs 70.0%), but more children than adults experienced pulmonary manifestations (37.5% vs 10.0%).

Conclusions: This evaluation provides insight into the diagnosis and management of aHUS in Canadian patients and the challenges faced. More genetic or anti-CFH antibody testing is needed to improve the diagnosis of aHUS, and the management of children and adults needs to consider several factors such as the risk of progression to ESRD is based on age (more likely in adults), and that the location of extrarenal manifestations differs in children and adults.
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http://dx.doi.org/10.1177/2054358119897229DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6984425PMC
January 2020

Using bioimpedance analysis to assess intensive care unit patients with sepsis in the post-resuscitation period: a prospective multicentre observational study.

Can J Anaesth 2020 04 20;67(4):437-444. Epub 2019 Dec 20.

Department of Medicine, McMaster University, Hamilton, ON, Canada.

Purpose: Clinicians lack well-validated, non-invasive, objective tools to guide volume management in the post-resuscitative period. Bioimpedance analysis (BIA) represents a novel method for guiding fluid management. We studied the relationship of BIA vector length (VL), an indicator of volume status, to the need for mechanical ventilation in patients with sepsis.

Methods: This is a multicentre prospective observational study at four Canadian ICUs. We examined adult patients admitted to the ICU within 72 hr of a sepsis diagnosis. Patients underwent daily BIA measurements for 30 days, until discharge from the ICU, or until death. Our primary outcome was the ongoing need for invasive mechanical ventilation, and we examined the association with VL using a generalized estimating equation. Our secondary analyses were targeted to determine an association between VL and other measures of volume status and acute kidney injury (AKI).

Results: We enrolled 159 patients from four centres over 27 months. The mean (standard deviation [SD]) age was 64 (15) yr with a mean (SD) APACHE (acute physiology, age, chronic health evaluation) II score of 25 (10); 57% (n = 91) were male. A 50-unit (ohm·m) increase in VL over any time period was associated with a 30% decrease in the probability of requiring invasive mechanical ventilation (P < 0.03). Volume expansion, indicated by a shorter VL, correlated with higher edema scores (r = - 0.31; P < 0.001) and higher net 24-hr fluid balance (r = - 0.27, P < 0.001). Patients with AKI had a shorter overall VL (r = - 0.23; P = 0.003).

Conclusions: An increase in VL over time is associated with a decrease in probability of requiring invasive mechanical ventilation. Vector length correlates with other commonly used volume assessment methods in post-resuscitation patients with sepsis.
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http://dx.doi.org/10.1007/s12630-019-01557-8DOI Listing
April 2020

Efficacy and safety of non-vitamin K antagonist oral anticoagulants post-kidney transplantation.

World J Transplant 2019 Oct;9(6):134-144

Department of Nephrology, McMaster University, Hamilton, ON L8N 4A6, Canada.

Background: Novel oral anticoagulants (NOACs) were developed as alternatives to vitamin K antagonists, primarily warfarin, as they do not require routine monitoring and have limited drug-drug and drug-food interactions. However, the efficacy and safety of these agents in kidney transplantation are not well studied.

Aim: To assess the profile and safety of NOACs for patients who had kidney transplantation, and to provide recommendations and guidelines on therapeutic strategies in these patients.

Methods: This was a retrospective study carried out among adult patients who were actively on the following NOACs (apixaban, rivaroxaban or dabigatran) in our renal transplantation program from December 2015 to December 2016. The patients were identified primarily through electronic medical record system (patient data linkage). Data on the clinical and laboratory profile of the patients were retrieved and analyzed with SPSS 22.0.

Results: Complete data on 42 renal transplant patients were retrieved: 59.5% males, 90.5% were whites and 66.7% were older than 60 years old. The mean duration since renal transplantation of the patients was 8.8 ± 7.4 years. The most common risk factors for the development of end-stage renal disease in the subjects were hypertension (19.0%), polycystic kidney disease (19.0%), followed by diabetic nephropathy (16.7%) and chronic glomerulonephritis (16.7%). The main indications for NOACs use in the cohort were atrial fibrillation in 25 patients (59.5%) and venous thromboembolism in 10 patients (23.8%). Overall, 29 patients (69%) were treated with apixaban, 10 patients (23.8%) with rivaroxaban and 3 patients (7.14%) with dabigatran. No (0%) thromboembolic events were observed during the one-year period, but 3 (7.1%) bleeding events occurred in the cohort consisting of 1 patient treated with rivaroxaban 15 mg daily and 2 patients who received apixaban 2.5 mg twice daily. There were no significant changes in serum tacrolimus level three days after the initiation of NOACs among patients treated with tacrolimus (pre- and post-NOACs tacrolimus levels were 7.2516 and 7.8867 ng/mL, = 0.55, respectively). Also, after one-year of treatment with NOACs there were no significant changes in the pre- and post-NOACs serum creatinine level ( = 0.772) and estimated glomerular filtration rates ( = 0.232).

Conclusion: No thromboembolic events or significant changes in renal profile were observed in our cohort of kidney transplant recipients who were treated with NOACs for at least a year. However, a few bleeding events were observed. This calls for further well-planned randomized controlled trials to assess the efficacy and safety of NOACs among renal transplant recipients.
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http://dx.doi.org/10.5500/wjt.v9.i6.134DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6851500PMC
October 2019

Influence of climate change and postdelisting management on long-term population viability of the conservation-reliant Kirtland's Warbler.

Ecol Evol 2019 Sep 24;9(18):10263-10276. Epub 2019 Aug 24.

Department of Biological and Environmental Sciences California University of Pennsylvania California PA USA.

Rapid global climate change is resulting in novel abiotic and biotic conditions and interactions. Identifying management strategies that maximize probability of long-term persistence requires an understanding of the vulnerability of species to environmental changes. We sought to quantify the vulnerability of Kirtland's Warbler (), a rare Neotropical migratory songbird that breeds almost exclusively in the Lower Peninsula of Michigan and winters in the Bahamian Archipelago, to projected environmental changes on the breeding and wintering grounds. We developed a population-level simulation model that incorporates the influence of annual environmental conditions on the breeding and wintering grounds, and parameterized the model using empirical relationships. We simulated independent and additive effects of reduced breeding grounds habitat quantity and quality, and wintering grounds habitat quality, on population viability. Our results indicated the Kirtland's Warbler population is stable under current environmental and management conditions. Reduced breeding grounds habitat quantity resulted in reductions of the stable population size, but did not cause extinction under the scenarios we examined. In contrast, projected large reductions in wintering grounds precipitation caused the population to decline, with risk of extinction magnified when breeding habitat quantity or quality also decreased. Our study indicates that probability of long-term persistence for Kirtland's Warbler will depend on climate change impacts to wintering grounds habitat quality and contributes to the growing literature documenting the importance of considering the full annual cycle for understanding population dynamics of migratory species.
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http://dx.doi.org/10.1002/ece3.5547DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6787827PMC
September 2019

Risk Factors for 1-Year Graft Loss After Kidney Transplantation: Systematic Review and Meta-Analysis.

Clin J Am Soc Nephrol 2019 11 20;14(11):1642-1650. Epub 2019 Sep 20.

Department of Health Research Methods, Evidence, and Impact and.

Background And Objectives: With expansion of the pool of kidney grafts, through the use of higher-risk donors, and increased attention to donor management strategies, the 1-year graft survival rate is subject to change. It is, therefore, useful to elucidate 1-year graft survival rates by dissecting the characteristics of the low-risk and high-risk kidney transplant cases. The objective of our study was to evaluate factors purported to influence the risk of 1-year graft loss in kidney transplant recipients.

Design, Setting, Participants, & Measurements: We searched bibliographic databases from 2000 to 2017 and included observational studies that measured the association between donor, recipient, the transplant operation, or early postoperative complications, and 1-year death-censored graft loss.

Results: We identified 35 eligible primary studies, with 20 risk factors amenable to meta-analysis. Six factors were associated with graft loss, with moderate to high degree of certainty: donor age (hazard ratio [HR], 1.11 per 10-year increase; 95% confidence interval [95% CI], 1.04 to 1.18), extended criteria donors (HR, 1.35; 95% CI, 1.28 to 1.42), deceased donors (HR, 1.54; 95% CI, 1.32 to 1.82), number of HLA mismatches (HR, 1.08 per one mismatch increase; 95% CI, 1.07 to 1.09), recipient age (HR, 1.17 per 10-year increase; 95% CI, 1.09 to 1.25), and delayed graft function (HR, 1.89; 95% CI, 1.46 to 2.47) as risk factors for 1-year graft loss. Pooled analyses also excluded, with a high degree of certainty, any associations of cold ischemia time, recipient race, pretransplant body mass index, diabetes, and hypertension with 1-year graft loss.

Conclusions: Recipient age, donor age, standard versus extended criteria donor, living versus deceased donor, HLA mismatch, and delayed graft function all predicted 1-year graft survival. The effect of each risk factor is small.
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http://dx.doi.org/10.2215/CJN.05560519DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6832056PMC
November 2019

Balancing the Benefits and Harms of Oral Anticoagulation in Chronic Kidney Disease: What Does Available Evidence Tell Us?

Ann Intern Med 2019 08 16;171(3):214-215. Epub 2019 Jul 16.

University of Ottawa, Ottawa, Ontario, Canada (D.Z.).

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http://dx.doi.org/10.7326/M19-1504DOI Listing
August 2019

Circulating microvesicle protein is associated with renal transplant outcome.

Transpl Immunol 2019 08 19;55:101210. Epub 2019 Jun 19.

Division of Nephrology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada; St. Joseph's Healthcare Research Institute & Hamilton Center for Kidney Research, Canada.

Renal transplantation is an effective therapy with improved long-term outcomes compared with other therapies for end stage renal disease. Present methods for evaluating kidney allograft function, such as serum creatinine or allograft biopsy, are not sensitive and identify pathological changes only after any potential intervention would be effective. Thus, there is a necessity for biomarkers that would provide early prognostic information about kidney transplant outcomes. Circulating microvesicles represent an attractive source of biomarkers for different diseases including renal failure. We have studied the proteins of the circulating microvesicles from two populations of kidney transplant recipients (n = 20) with poor transplant outcomes (n = 10) or good transplant outcome (n = 10), according to their estimated glomerular filtration rate (eGFR). Microvesicles from age-matched healthy subjects (n = 10) were used as a control. Also, we performed a pilot study to assess the microvesicle protein in kidney transplant recipients before and six months after kidney transplant (n = 6), compared to healthy subjects. Proteomic analysis of microvesicles could discriminate between transplant recipients and healthy subjects, and between transplant patients based on eGFR. Our results shed light on the potential of blood microvesicles to provide a novel tool for the prediction of the outcome of kidney transplants.
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http://dx.doi.org/10.1016/j.trim.2019.06.002DOI Listing
August 2019

Crusted scabies in a renal transplant recipient treated with daily ivermectin: A case report and literature review.

Transpl Infect Dis 2019 Jun 29;21(3):e13077. Epub 2019 Mar 29.

Division of Nephrology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.

Crusted scabies is a rare disease variant associated with T-cell dysregulation. Transplant patients are at risk of developing crusted scabies as a consequence of their immunosuppressive regimens. We report a case of crusted scabies presenting with recurrent septicemia in a 65-year-old renal transplant recipient, treated with daily ivermectin for 7 days after initial failure of weekly ivermectin dosing. A literature review of crusted scabies in transplant recipients consisting of 19 cases reports was summarized. Pruritus was common, and initial misdiagnosis was frequent. Most were treated with topical therapy, with one-third receiving ivermectin. Three of seven cases presenting with a concomitant infection died. Crusted scabies is commonly misdiagnosed in transplant recipients owing to its rarity, varied appearance, and different skin distributions. It should be considered in the differential diagnosis of transplant recipients presenting with rash and pruritus, given its association with secondary infection and subsequent mortality.
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http://dx.doi.org/10.1111/tid.13077DOI Listing
June 2019

Message in a bottle - The story of floating plastic in the eastern Mediterranean sea.

Waste Manag 2018 Jul 11;77:67-77. Epub 2018 May 11.

U.S. Geological Survey, Wisconsin Cooperative Wildlife Research Unit, Department of Forest and Wildlife Ecology, University of Wisconsin, Madison, WI, USA. Electronic address:

The Mediterranean Sea is a closed basin with limited water exchange through the Strait of Gibraltar, and sites along its shores show the greatest densities of marine debris in the world. Plastic bottles, which are a growing concern due to high consumption of soft drinks and bottled water, constitute most of the floating marine debris. In this paper we present the transport mechanisms of floating marine debris to and from the Israeli coast using an experimental offshore release and recovery of plastic bottles, with the participation of citizens. Many bottles released near the beach in the south part of Israel, returned to the beach at a short distance and time from the release point. Some release locations had no bottle returns. Ten bottles, released from three locations, were recovered many dozens to hundreds of kilometers from the release point. Since most of the westward water flow in the eastern Mediterranean is subsurface, it was not surprising to find our floating debris only in the east. That makes the Levant basin in the eastern Mediterranean a collection area for floating debris.
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http://dx.doi.org/10.1016/j.wasman.2018.04.034DOI Listing
July 2018

Hamilton-DONATE: a city-wide pilot observational study of the ICU management of deceased organ donors.

Can J Anaesth 2018 10 9;65(10):1110-1119. Epub 2018 Jul 9.

Department of Medicine, McMaster University, Hamilton, ON, Canada.

Purpose: Improving the medical care of deceased organ donors to increase transplant rates and improve allograft function requires an understanding of the current epidemiology and clinical practices of deceased donation within intensive care units (ICUs). Herein, we report the results of our investigation into the feasibility of a multicentre prospective cohort study addressing the afformentioned issues.

Methods: We conducted a 12-month prospective observational cohort study in six ICUs and one coronary care unit in Hamilton, Canada. We included consecutive children and adults following consent for deceased organ donation (including neurologic determination of death [NDD] or donation after circulatory death [DCD]). Intensive care unit research staff recorded donor management data from hospital records, extending from one day prior to the consent for organ donation up to the time of organ retrieval. The provincial Organ Donation Organization (ODO) supplemented these data and, additionally, provided data on corresponding organ recipients. We identified, evaluated, and measured three potential obstacles to the feasibility of a national cohort study: obtaining authorization to implement the study with a waiver of research consent, accessibility of transplant recipient data, and the time required to complete very detailed case report forms (CRFs), with valuable lessons learned for implementation in future projects.

Results: The local Research Ethics Board and the ODO Privacy Office both authorized the recording of donor and recipient study data with a waiver of research consent. Sixty-seven consecutive consented donors were included (31 NDD and 36 DCD donors); 50 of them provided 144 organs for transplantation to 141 recipients. We identified the age and sex of the recipients as well as the location and date of transplant for all organ recipients in Ontario; however, we obtained no recipient data for six organs transported outside of Ontario. Intensive care unit research staff estimated that future CRF completion will require five to seven hours per patient.

Conclusion: The Hamilton-DONATE pilot study supports the feasibility of a larger cohort study to describe the epidemiology and clinical practices related to deceased donor care in Canada.

Trial Registration: wwwclinicaltrials.gov (NCT02902783). Registered 16 September 2016.
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http://dx.doi.org/10.1007/s12630-018-1179-yDOI Listing
October 2018

Transfusion Management of Incident Dialysis Patients in Canada: A Prospective Observational Study.

Can J Kidney Health Dis 2018 5;5:2054358118778564. Epub 2018 Jun 5.

University Western Ontario, London, Canada.

Background: Several studies have demonstrated harm associated with using erythropoiesis-stimulating agents (ESA) to achieve higher hemoglobin (Hb) levels. Subsequently, more conservative use of ESAs has changed anemia therapy in patients with chronic renal failure.

Objective: The objectives were to identify transfusion rates in hemodialysis (HD) patients during the first year of therapy, to identify factors associated with the probability of transfusion, describe reasons for the transfusions, and identify the Hb values associated with each transfusion. An exploratory objective was to describe the age of red blood cell transfusions.

Design: This was a multicenter prospective observational cohort study.

Setting: There were 12 study sites in 5 Canadian provinces. The study was performed from 2012 to 2014.

Methods: The study patients were adult incident chronic HD patients in these centers. Patients with acute kidney injury, peritoneal dialysis, and planned transfer to satellite units were excluded. Patients had to receive at least 1 month of chronic HD to be eligible. Data for 3 months prior to HD were obtained by retrospective chart review. Prospectively, charts were reviewed monthly for 12 months for data abstraction.

Results: There were 314 patients enrolled and 79.9% completed 12 month follow-up. Ninety-four (29.9%) patients received at least 1 unit of blood. During the first 90 days, the transfusion episode rate was 148.4 per 100 patient-years compared with 62.6 per 100 patient-years post 90 days. The most frequent indication was a low Hb value (92%) with gastrointestinal bleeding, surgical blood loss, and fatigue accounting for 9.9%, 8.6%, and 4.5%, respectively. Some patients had >1 indication. The mean Hb values prior to transfusion episodes ranged from 75.3 to 78.6 g/L. Cox regression analysis on time to first transfusion and time to first hospitalization/death both showed an association with inpatient initiation of HD. Some 37.5% initiated HD as an inpatient and differed from those starting as an outpatient. They had less predialysis care and laboratory data suggested more inflammation. The mean and median ages of the blood units transfused were 24.9 (SD = 10.0) and 23 days (interquartile range = 17-33).

Conclusions: This work reported the blood transfusion rate in incident HD patients in Canada during a period associated with conservative ESA prescription. The major indication for transfusion was a low Hb rather than clinical symptoms. Initiation of HD as an inpatient was independently associated with the probability of receiving a blood transfusion. These findings require further investigation.
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http://dx.doi.org/10.1177/2054358118778564DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5992794PMC
June 2018

Effects of temperature and precipitation on grassland bird nesting success as mediated by patch size.

Conserv Biol 2018 08 25;32(4):872-882. Epub 2018 Apr 25.

The Nature Conservancy Center for Science and Public Policy, Tucson, AZ 85719, U.S.A.

Grassland birds are declining faster than any other bird guild across North America. Shrinking ranges and population declines are attributed to widespread habitat loss and increasingly fragmented landscapes of agriculture and other land uses that are misaligned with grassland bird conservation. Concurrent with habitat loss and degradation, temperate grasslands have been disproportionally affected by climate change relative to most other terrestrial biomes. Distributions of grassland birds often correlate with gradients in climate, but few researchers have explored the consequences of weather on the demography of grassland birds inhabiting a range of grassland fragments. To do so, we modeled the effects of temperature and precipitation on nesting success rates of 12 grassland bird species inhabiting a range of grassland patches across North America (21,000 nests from 81 individual studies). Higher amounts of precipitation in the preceding year were associated with higher nesting success, but wetter conditions during the active breeding season reduced nesting success. Extremely cold or hot conditions during the early breeding season were associated with lower rates of nesting success. The direct and indirect influence of temperature and precipitation on nesting success was moderated by grassland patch size. The positive effects of precipitation in the preceding year on nesting success were strongest in relatively small grassland patches and had little effect in large patches. Conversely, warm temperatures reduced nesting success in small grassland patches but increased nesting success in large patches. Mechanisms underlying these differences may be patch-size-induced variation in microclimates and predator activity. Although the exact cause is unclear, large grassland patches, the most common metric of grassland conservation, appears to moderate the effects of weather on grassland-bird demography and could be an effective component of climate-change adaptation.
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http://dx.doi.org/10.1111/cobi.13089DOI Listing
August 2018

Canada-DONATE study protocol: a prospective national observational study of the medical management of deceased organ donors.

BMJ Open 2017 Sep 28;7(9):e018858. Epub 2017 Sep 28.

Department of Medicine, McMaster University, Hamilton, Ontario, Canada.

Introduction: Research on the management of deceased organ donors aims to improve the number and quality of transplants and recipient outcomes. In Canada, this research is challenged by regionalisation of donation services within provinces and the geographical, clinical and administrative separation of donation from transplantation services. This study aims to build a national platform for future clinical trials in donor management. Objectives are to engage collaborators at donation hospitals and organ donation organisations (ODOs) across Canada, describe current practices, evaluate the effectiveness of donation-specific interventions and assess the feasibility of future clinical trials.

Methods And Analysis: This ongoing prospective observational study of the medical management of deceased organ donors will enrol more than 650 consented potential donors from adult intensive care units at 33 hospital sites across Canada, each participating for 12 months. ODOs ensure enrolment of consecutive eligible participants. Research staff record detailed data about participants, therapies, organ assessments, death declaration procedures and adverse clinical exposures from the time of donation consent to organ recovery. ODOs provide reasons that organs are declined, dates and places of transplantation, and recipient age and sex.Descriptive analyses will summarise current practices. Effectiveness analyses will examine donation-specific interventions with respect to the number of transplants, using multilevel regression models to account for clustering by donor, hospitals and ODOs. Feasibility analyses will focus on acceptance of the research consent model; participation of academic and community hospitals as well as ODOs; and accessibility of recipient data.

Ethics And Dissemination: This study uses a waiver of research consent. Hospitals will receive reports on local practices benchmarked to (1) national practices and (2) national donor management guidelines. We will report findings to donation and transplant collaborators (ie, clinicians, researchers, ODOs) and publish in peer-reviewed journals.

Trial Registration Number: NCT03114436.
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http://dx.doi.org/10.1136/bmjopen-2017-018858DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5640087PMC
September 2017

Study of Cardiovascular Outcomes in Renal Transplantation: A Prospective, Multicenter Study to Determine the Incidence of Cardiovascular Events in Renal Transplant Recipients in Ontario, Canada.

Can J Kidney Health Dis 2017 14;4:2054358117713729. Epub 2017 Jun 14.

Division of Nephrology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.

Background: Renal transplant recipients (RTRs) are at significantly higher risk for morbidity and mortality compared with the general population, largely attributed to cardiovascular disease (CVD). Previous estimates of CVD events have come from health care databases and retrospective studies.

Objective: The objective of this study was to prospectively determine the prevalence of risk factors and incidence of CVD events in a Canadian cohort of RTRs.

Design: Study of Cardiovascular Outcomes in Renal Transplantation (SCORe) was a prospective, longitudinal, multicenter observational study.

Setting: Adult RTRs were recruited from 6 participating transplant sites in Ontario, Canada.

Patients: Eligible patients were those receiving a living or deceased donor renal transplant. Patients who received simultaneous transplant of any other organ were excluded.

Measurements: Primary outcomes included myocardial infarction (MI) defined by American College of Cardiology (ACC-MI) criteria, and major adverse cardiac events (MACE), defined as cardiovascular (CV) death, ACC-MI, coronary revascularization, and nonhemorrhagic stroke. CV events were adjudicated by a single, independent cardiologist.

Methods: CV and transplant-specific risk factors that predict MACE and ACC-MI were identified by stepwise regression analysis using the Cox proportional hazards model.

Results: A total of 1303 patients enrolled across 6 transplant centers were followed for 4.5 ± 1.6 years (mean ± SD). Incidence of MACE was 7.0%, with significant independent predictors/risk factors including age, diabetes, coronary revascularization, nonhemorrhagic stroke, and renal replacement therapy (RRT). ACC-MI incidence was 4.0%, with significant independent predictors/risk factors including age, coronary revascularization, and duration of RRT in excess of the median value (2.91 years).

Limitations: Patients were recruited from a single province, so may not reflect the experience of RTRs in other areas of Canada.

Conclusions: Using a prospective design and rigorous methodology, this study found that the incidence of CV events after renal transplantation was elevated relative to the general Canadian population and was comparable with that reported in patient registries, thus helping validate the utility of retrospective analysis in this field. SCORe highlights the importance of monitoring RTRs for traditional cardiac and transplant-specific CV risk factors to help prevent CV morbidity and mortality. Further research is needed to investigate a broader range of potential risk factors and their combined effects on incident CV events.
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http://dx.doi.org/10.1177/2054358117713729DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5476328PMC
June 2017

Beaver Colony Density Trends on the Chequamegon-Nicolet National Forest, 1987 - 2013.

PLoS One 2017 12;12(1):e0170099. Epub 2017 Jan 12.

Chequamegon-Nicolet National Forest, US Forest Service, Park Falls, Wisconsin, United States of America.

The North American beaver (Castor canadensis) is a managed species in the United States. In northern Wisconsin, as part of the state-wide beaver management program, the Chequamegon-Nicolet National Forest removes beavers from targeted trout streams on U.S. Forest Service lands. However, the success of this management program has not been evaluated. Targeted removals comprise only 3% of the annual beaver harvest, a level of effort that may not affect the beaver population. We used colony location data along Forest streams from 1987-2013 (Nicolet, northeast Wisconsin) and 1997-2013 (Chequamegon, northwest Wisconsin) to assess trends in beaver colony density on targeted trout streams compared to non-targeted streams. On the Chequamegon, colony density on non-targeted trout and non-trout streams did not change over time, while colony density on targeted trout streams declined and then stabilized. On the Nicolet, beaver colony density decreased on both non-targeted streams and targeted trout streams. However, colony density on targeted trout streams declined faster. The impact of targeted trapping was similar across the two sides of the Forest (60% reduction relative to non-targeted trout streams). Exploratory analyses of weather influences found that very dry conditions and severe winters were associated with transient reductions in beaver colony density on non-targeted streams on both sides of the Forest. Our findings may help land management agencies weigh more finely calibrated beaver control measures against continued large-scale removal programs.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0170099PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5231324PMC
August 2017

Thrombosis and anticoagulation in the setting of renal or liver disease.

Hematology Am Soc Hematol Educ Program 2016 Dec;2016(1):188-195

Department of Medicine and Department of Pathology and Molecular Medicine, McMaster University, and St Joseph's Healthcare, Hamilton, ON, Canada.

Thrombosis and bleeding are among the most common causes of morbidity and mortality in patients with renal disease or liver disease. The pathophysiology underlying the increased risk for venous thromboembolism and bleeding in these 2 populations is distinct, as are considerations for anticoagulation. Anticoagulation in patients with kidney or liver disease increases the risk of bleeding; this risk is correlated with the degree of impairment of anticoagulant elimination by the kidneys and/or liver. Despite being in the same pharmacologic category, anticoagulant agents may have varied degrees of renal and liver metabolism. Therefore, specific anticoagulants may require dose reductions or be contraindicated in renal impairment and liver disease, whereas other drugs in the same class may not be subject to such restrictions. To minimize the risk of bleeding, while ensuring an adequate therapeutic effect, both appropriate anticoagulant drug choices and dose reductions are necessary. Renal and hepatic function may fluctuate, further complicating anticoagulation in these high-risk patient groups.
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http://dx.doi.org/10.1182/asheducation-2016.1.188DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6142494PMC
December 2016

Sources, composition and spatial distribution of marine debris along the Mediterranean coast of Israel.

Mar Pollut Bull 2017 Jan 23;114(2):1036-1045. Epub 2016 Nov 23.

Department of Maritime Civilizations, The Leon H. Charney School for Marine Sciences, University of Haifa, 199 Aba-Khoushi Avenue, Mount Carmel, Haifa 3498838, Israel; The Leon Recanati Institute for Maritime Studies, The Leon H. Charney School for Marine Sciences, University of Haifa, 199 Aba-Khoushi Avenue, Mount Carmel, Haifa 3498838, Israel.

Marine debris (litter) is a complex problem that affects human activities and the marine environment worldwide. The Clean Coast Program in Israel has had some success in keeping most of the coasts clean most of the time, but without understanding the mechanisms of accumulation of marine debris on the coasts of Israel. In 2012, we initiated a study to characterize the types of marine debris, its origins and spatial distribution. Nineteen surveys were done from June 2012 to March 2015 on eight beaches that spanned the coast of Israel. Average debris density was 12.1 items per 100m and 90% of the items were plastic. The top debris categories were food wrappers and disposables, plastic bags and cigarette butts. However, there was variation in the top debris categories among the beaches indicating that a flexible approach with multiple options will be important when addressing the marine debris problem.
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http://dx.doi.org/10.1016/j.marpolbul.2016.11.023DOI Listing
January 2017

Assessment of Postresuscitation Volume Status by Bioimpedance Analysis in Patients with Sepsis in the Intensive Care Unit: A Pilot Observational Study.

Can Respir J 2016 15;2016:8671742. Epub 2016 Aug 15.

Department of Medicine, McMaster University, Hamilton, ON, Canada; Division of Nephrology, St. Joseph's Healthcare Hamilton, Hamilton, ON, Canada.

Background. Bioimpedance analysis (BIA) is a novel method of assessing a patient's volume status. Objective. We sought to determine the feasibility of using vector length (VL), derived from bioimpedance analysis (BIA), in the assessment of postresuscitation volume status in intensive care unit (ICU) patients with sepsis. Method. This was a prospective observational single-center study. Our primary outcome was feasibility. Secondary clinical outcomes included ventilator status and acute kidney injury. Proof of concept was sought by correlating baseline VL measurements with other known measures of volume status. Results. BIA was feasible to perform in the ICU. We screened 655 patients, identified 78 eligible patients, and approached 64 for consent. We enrolled 60 patients (consent rate of 93.8%) over 12 months. For each 50-unit increase in VL, there was an associated 22% increase in the probability of not requiring invasive mechanical ventilation (IMV) (p = 0.13). Baseline VL correlated with other measures of volume expansion including serum pro-BNP levels, peripheral edema, and central venous pressure (CVP). Conclusion. It is feasible to use BIA to predict postresuscitation volume status and patient-important outcomes in septic ICU patients. Trial Registration. This trial is registered with clinicaltrials.gov NCT01379404 registered on June 7, 2011.
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http://dx.doi.org/10.1155/2016/8671742DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5002474PMC
July 2017

The Risk of Cardiovascular Disease Is Not Increasing Over Time Despite Aging and Higher Comorbidity Burden of Kidney Transplant Recipients.

Transplantation 2017 03;101(3):588-596

1 Division of Nephrology, Department of Medicine, University of Alberta, Edmonton, AB, Canada. 2 Division of Nephrology, Department of Medicine, University of Toronto, Toronto, ON, Canada. 3 Division of Nephrology, Department of Medicine, University of Ottawa, Ottawa, ON, Canada. 4 Clinical Epidemiology Program, Ottawa Health Research Institute, Ottawa, ON, Canada. 5 Institute for Clinical Evaluative Sciences (ICES), Toronto, ON, Canada. 6 Center for Outcomes Research, Saint Louis University School of Medicine, St. Louis, MO. 7 Division of Abdominal Transplantation, Department of Surgery, Saint Louis University School of Medicine, St. Louis, MO. 8 Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada. 9 Department of Epidemiology and Biostatistics, Western University, London, ON, Canada. 10 Division of Nephrology, Department of Medicine, McMaster University, Hamilton, ON, Canada. 11 Division of Nephrology, Department of Medicine, Western University, London, ON.

Background: Cardiovascular death remains the leading cause of mortality in kidney transplant recipients. Cardiovascular events are associated with significant morbidity. However, current trends in cardiovascular events after kidney transplantation are poorly understood.

Methods: We conducted a retrospective study using healthcare databases in Ontario, Canada, to determine whether the incidence of cardiovascular events after kidney transplantation has changed from 1994 to 2009. Our primary endpoint was a 3-year composite outcome of posttransplant death or major cardiovascular event (myocardial infarction, coronary angioplasty, coronary artery bypass graft surgery, stroke).

Results: Recipients (n = 4954) were older and had more baseline comorbidity in recent years. A total of 445 recipients (9.0%) died or experienced a major cardiovascular event within 3 years of transplantation. There was no significant change in the incidence of the composite outcome or death-censored cardiovascular events over time (P = 0.41 and 0.92, respectively). After adjusting for age, sex, and comorbidities, the risk of death or major cardiovascular event steadily declined across the years of transplant (2006-2009 adjusted hazard ratio, 0.70; P = 0.009; referent 1994-1997). When recipients were matched on age, sex, and date of cohort entry to members of the general population and to the chronic kidney disease population, the risk was lowest in the general population and highest in the chronic kidney disease population.

Conclusion: Despite transplant centers accepting recipients who are older with more comorbidities in recent years, the 3-year cumulative incidence of death or major cardiovascular event has remained stable over time.
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http://dx.doi.org/10.1097/TP.0000000000001155DOI Listing
March 2017

Strategic Grassland Bird Conservation throughout the Annual Cycle: Linking Policy Alternatives, Landowner Decisions, and Biological Population Outcomes.

PLoS One 2015 16;10(11):e0142525. Epub 2015 Nov 16.

Wisconsin Department of Natural Resources, Madison, WI, United States of America.

Grassland bird habitat has declined substantially in the United States. Remaining grasslands are increasingly fragmented, mostly privately owned, and vary greatly in terms of habitat quality and protection status. A coordinated strategic response for grassland bird conservation is difficult, largely due to the scope and complexity of the problem, further compounded by biological, sociological, and economic uncertainties. We describe the results from a collaborative Structured Decision Making (SDM) workshop focused on linking social and economic drivers of landscape change to grassland bird population outcomes. We identified and evaluated alternative strategies for grassland bird conservation using a series of rapid prototype models. We modeled change in grassland and agriculture cover in hypothetical landscapes resulting from different landowner decisions in response to alternative socio-economic conservation policy decisions. Resulting changes in land cover at all three stages of the annual cycle (breeding, wintering, and migration) were used to estimate changes in grassland bird populations. Our results suggest that successful grassland bird conservation may depend upon linkages with ecosystem services on working agricultural lands and grassland-based marketing campaigns to engage the public. With further development, spatial models that link landowner decisions with biological outcomes can be essential tools for making conservation policy decisions. A coordinated non-traditional partnership will likely be necessary to clearly understand and systematically respond to the many conservation challenges facing grassland birds.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0142525PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4646652PMC
June 2016

Relatively high prevalence of pox-like lesions in Henslow's sparrow (Ammodrammus henslowii) among nine species of migratory grassland passerines in Wisconsin, USA.

J Wildl Dis 2014 Oct 14;50(4):810-6. Epub 2014 Aug 14.

1  Department of Forest and Wildlife Ecology, University of Wisconsin, 1630 Linden Dr., Madison, Wisconsin 53706, USA.

Globally, Avipoxvirus species affect over 230 species of wild birds and can significantly impair survival. During banding of nine grassland songbird species (n=346 individuals) in southwestern Wisconsin, USA, we noted species with a 2-6% prevalence of pox-like lesions (possible evidence of current infection) and 4-10% missing digits (potential evidence of past infection). These prevalences approach those recorded among island endemic birds (4-9% and 9-20% for the Galapagos and Hawaii, respectively) for which Avipoxvirus species have been implicated as contributing to dramatic population declines. Henslow's Sparrow Ammodramus henslowii (n=165 individuals) had the highest prevalence of lesions (6.1%) and missing digits (9.7%). Among a subset of 26 Henslow's Sparrows from which blood samples were obtained, none had detectable antibody reactive to fowlpox virus antigen. However, four samples (18%) had antibody to canarypox virus antigen with test sample and negative control ratios (P/N values) ranging from 2.4 to 6.5 (median 4.3). Of four antibody-positive birds, two had lesions recorded (one was also missing a digit), one had digits missing, and one had no signs. Additionally, the birds with lesions or missing digits had higher P/N values than did the antibody-positive bird without missing digits or recorded lesions. This study represents an impetus for considering the impacts and dynamics of disease caused by Avipoxvirus among North American grassland bird species.
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http://dx.doi.org/10.7589/2013-09-252DOI Listing
October 2014

The impact of patient preference on dialysis modality and hemodialysis vascular access.

BMC Nephrol 2014 Feb 22;15:38. Epub 2014 Feb 22.

FRCP(C), Division of Nephrology, Department of Medicine, McMaster University, 50 Charlton Ave, E, Hamilton, ON L8N 4A6, Canada.

Background: Home-based dialysis, including peritoneal dialysis (PD) and home hemodialysis (HHD), is associated with improved health related quality of life and reduced health resource costs. It is uncertain to what extent initial preferences for dialysis modality influence the first dialysis therapy actually utilized. We examined the relationship between initial dialysis modality choice and first dialysis therapy used.

Methods: Patients with chronic kidney disease (CKD) from a single centre who started dialysis after receiving modality education were included in this study. Multivariable logistic regression models were constructed to assess the independent association of patient characteristics and initial dialysis modality choice with actual dialysis therapy used and starting hemodialysis (HD) with a central venous catheter (CVC).

Results: Of 299 eligible patients, 175 (58.5%) initially chose a home-based therapy and 102 (58.3%) of these patients' first actual dialysis was a home-based therapy. Of the 89 patients that initially chose facility-based HD, 84 (94.4%) first actual dialysis was facility-based HD. The adjusted odds ratio (OR) for first actual dialysis as a home-based therapy was 29.0 for patients intending to perform PD (95% confidence interval [CI] 10.7-78.8; p < 0.001) and 12.4 for patients intending to perform HHD (95% CI 3.29-46.6; p < 0.001). Amongst patients whose first actual dialysis was HD, an initial choice of PD or not choosing a modality was associated with an increased risk of starting dialysis with a CVC (adjusted OR 3.73, 95% CI 1.51-9.21; p = 0.004 and 4.58, 95% CI 1.53-13.7; p = 0.007, respectively).

Conclusions: Although initially choosing a home-based therapy substantially increases the probability of the first actual dialysis being home-based, many patients who initially prefer a home-based therapy start with facility-based HD. Programs that continually re-evaluate patient preferences and reinforce the values of home based therapies that led to the initial preference may improve home-based therapy uptake and improve preparedness for starting HD.
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http://dx.doi.org/10.1186/1471-2369-15-38DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3943442PMC
February 2014

The statistical significance of randomized controlled trial results is frequently fragile: a case for a Fragility Index.

J Clin Epidemiol 2014 Jun 5;67(6):622-8. Epub 2014 Feb 5.

Department of Clinical Epidemiology and Biostatistics, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada, L8S4L8; Department of Medicine, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada, L8S4L8; Population Health Research Institute, Hamilton Health Sciences and McMaster University, 237 Barton St East, Hamilton, Ontario, Canada, L8L2X2.

Objectives: A P-value <0.05 is one metric used to evaluate the results of a randomized controlled trial (RCT). We wondered how often statistically significant results in RCTs may be lost with small changes in the numbers of outcomes.

Study Design And Setting: A review of RCTs in high-impact medical journals that reported a statistically significant result for at least one dichotomous or time-to-event outcome in the abstract. In the group with the smallest number of events, we changed the status of patients without an event to an event until the P-value exceeded 0.05. We labeled this number the Fragility Index; smaller numbers indicated a more fragile result.

Results: The 399 eligible trials had a median sample size of 682 patients (range: 15-112,604) and a median of 112 events (range: 8-5,142); 53% reported a P-value <0.01. The median Fragility Index was 8 (range: 0-109); 25% had a Fragility Index of 3 or less. In 53% of trials, the Fragility Index was less than the number of patients lost to follow-up.

Conclusion: The statistically significant results of many RCTs hinge on small numbers of events. The Fragility Index complements the P-value and helps identify less robust results.
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http://dx.doi.org/10.1016/j.jclinepi.2013.10.019DOI Listing
June 2014

Impacts of tree rows on grassland birds and potential nest predators: a removal experiment.

PLoS One 2013 2;8(4):e59151. Epub 2013 Apr 2.

Department of Forest and Wildlife Ecology, University of Wisconsin, Madison, Wisconsin, United States of America.

Globally, grasslands and the wildlife that inhabit them are widely imperiled. Encroachment by shrubs and trees has widely impacted grasslands in the past 150 years. In North America, most grassland birds avoid nesting near woody vegetation. Because woody vegetation fragments grasslands and potential nest predator diversity and abundance is often greater along wooded edge and grassland transitions, we measured the impacts of removing rows of trees and shrubs that intersected grasslands on potential nest predators and the three most abundant grassland bird species (Henslow's sparrow [Ammodramus henslowii], Eastern meadowlark [Sturnella magna], and bobolink [Dolichonyx oryzivorus]) at sites in Wisconsin, U.S.A. We monitored 3 control and 3 treatment sites, for 1 yr prior to and 3 yr after tree row removal at the treatment sites. Grassland bird densities increased (2-4 times for bobolink and Henslow's sparrow) and nesting densities increased (all 3 species) in the removal areas compared to control areas. After removals, Henslow's sparrows nested within ≤50 m of the treatment area, where they did not occur when tree rows were present. Most dramatically, activity by woodland-associated predators nearly ceased (nine-fold decrease for raccoon [Procyon lotor]) at the removals and grassland predators increased (up to 27 times activity for thirteen-lined ground squirrel [Ictidomys tridecemlineatus]). Nest success did not increase, likely reflecting the increase in grassland predators. However, more nests were attempted by all 3 species (175 versus 116) and the number of successful nests for bobolinks and Henslow's sparrows increased. Because of gains in habitat, increased use by birds, greater production of young, and the effective removal of woodland-associated predators, tree row removal, where appropriate based on the predator community, can be a beneficial management action for conserving grassland birds and improving fragmented and degraded grassland ecosystems.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0059151PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3614982PMC
October 2013

Baseline for beached marine debris on Sand Island, Midway Atoll.

Mar Pollut Bull 2012 Aug 9;64(8):1726-9. Epub 2012 May 9.

US Geological Survey, Wisconsin Cooperative Wildlife Research Unit, Department of Forest and Wildlife Ecology, University of Wisconsin, 218 Russell Labs, 1630 Linden Drive, Madison, WI 53706, USA.

Baseline measurements were made of the amount and weight of beached marine debris on Sand Island, Midway Atoll, June 2008-July 2010. On 23 surveys, 32,696 total debris objects (identifiable items and pieces) were collected; total weight was 740.4 kg. Seventy-two percent of the total was pieces; 91% of the pieces were made of plastic materials. Pieces were composed primarily of polyethylene and polypropylene. Identifiable items were 28% of the total; 88% of the identifiable items were in the fishing/aquaculture/shipping-related and beverage/household products-related categories. Identifiable items were lowest during April-August, while pieces were at their lowest during June-August. Sites facing the North Pacific Gyre received the most debris and proportionately more pieces. More debris tended to be found on Sand Island when the Subtropical Convergence Zone was closer to the Atoll. This information can be used for potential mitigation and to understand the impacts of large-scale events such as the 2011 Japanese tsunami.
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http://dx.doi.org/10.1016/j.marpolbul.2012.04.001DOI Listing
August 2012

Trends in marine debris along the U.S. Pacific Coast and Hawai'i 1998-2007.

Mar Pollut Bull 2012 May 3;64(5):994-1004. Epub 2012 Mar 3.

U.S. Geological Survey, Wisconsin Cooperative Wildlife Research Unit, Department of Forest and Wildlife Ecology, University of Wisconsin, 218 Russell Labs, 1630 Linden Drive, Madison, WI 53706, USA.

We assessed amounts, composition, and trends of marine debris for the U.S. Pacific Coast and Hawai'i using National Marine Debris Monitoring Program data. Hawai'i had the highest debris loads; the North Pacific Coast region had the lowest debris loads. The Southern California Bight region had the highest land-based debris loads. Debris loads decreased over time for all source categories in all regions except for land-based and general-source loads in the North Pacific Coast region, which were unchanged. General-source debris comprised 30-40% of the items in all regions. Larger local populations were associated with higher land-based debris loads across regions; the effect declined at higher population levels. Upwelling affected deposition of ocean-based and general-source debris loads but not land-based loads along the Pacific Coast. LNSO decreased debris loads for both land-based and ocean-based debris but not general-source debris in Hawai'i, a more complex climate-ocean effect than had previously been found.
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http://dx.doi.org/10.1016/j.marpolbul.2012.02.008DOI Listing
May 2012
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