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Copyright of Canadian Studies in Population is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We consider a weighted local linear estimator based on the inverse selection probability for nonparametric regression with missing covariates at random. The asymptotic distribution of the maximal deviation between the estimator and the true regression function is derived and an asymptotically accurate simultaneous confidence band is constructed. The estimator for the regression function is shown to be oracally efficient in the sense that it is uniformly indistinguishable from that when the selection probabilities are known. Finite sample performance is examined via simulation studies which support our asymptotic theory. The proposed method is demonstrated via an analysis of a data set from the Canada 2010/2011 Youth Student Survey. [ABSTRACT FROM AUTHOR]

Objectives: The Canadian Triage and Acuity Scale (CTAS) is a five-level triage tool that is used to help prioritize the order in which emergency department (ED) patients should be seen. The objectives of this study were to determine the interrater and intrarater agreement of the 2008 CTAS guideline revisions by triage nurses and to compare agreement between triage nurses working in a small community ED and an academic ED. Methods: Seventy-eight triage nurses assigned CTAS scores and free-text presenting complaints for 10 paper-based case scenarios. For five scenarios, the CTAS score should have remained unchanged from previous guidelines, whereas the other five scenarios should have been triaged differently based on the 2008 CTAS first-order modifiers. Thirty-three participants repeated the questionnaire 90 days later, and intrarater agreement was measured. Results: There was a higher level of agreement (k = 0.73; 95% CI 0.68-0.79) for the five case scenarios, which relied on the older 2004 guidelines compared to the scenarios where the 2008 guidelines would have suggested a different triage level (k = 0.50; 95% CI 0.42-0.59). For the 10 case scenarios analyzed, the free-text presenting complaints matched the Canadian Emergency Department Information System (CEDIS) list 90.1% of the time (k = 0.80; 95% CI 0.76-0.84). Conclusion: The reliability of CTAS scoring by academic and community ED nurses was relatively good; however, the application of the 2008 CTAS revisions appears less reliable than the 2004 CTAS guidelines. These results may be useful to develop educational materials to strengthen reliability and validity for triage scoring using the 2008 CTAS guideline revisions. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Studies in Population is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective:Assess association of NICU size, and occupancy rate and resource utilization at admission with neonatal outcome.Study Design:Retrospective cohort study of 9978 infants born at 23-32 weeks gestation and admitted to 23 tertiary-level Canadian NICUs during 2010-2012. Adjusted odds ratios (AOR) were estimated for a composite outcome of mortality/any major morbidity with respect to NICU size, occupancy rate and intensity of resource utilization at admission.Results:A total of 2889 (29%) infants developed the composite outcome, the odds of which were higher for 16-29, 30-36 and >36-bed NICUs compared with <16-bed NICUs (AOR (95% CI): 1.47 (1.25-1.73); 1.49 (1.25-1.78); 1.55 (1.29-1.87), respectively) and for NICUs with higher resource utilization at admission (AOR: 1.30 (1.08-1.56), Q4 vs Q1) but not different according to NICU occupancy.Conclusion:Larger NICUs and more intense resource utilization at admission are associated with higher odds of a composite adverse outcome in very preterm infants. [ABSTRACT FROM AUTHOR]

Objective:Risks have been a central concern in stem cell research overall, and in clinical trials of individuals with spinal cord injury (ISCIs) in particular. We sought to elucidate how two important stakeholder groups-health-care professionals (HCPs) and ISCIs-view and value both the physical and non-physical risks of stem cell interventions.Setting:The study was conducted in Canada, and included participants from both Canada and the United States America.Study design:We used semi-structured interviews to gain perspectives on risk from HCPs and ISCIs.Methods:We applied a constant comparative analytic strategy to derive themes from the discourse collected through the interviews.Results:We identified three major themes about risk from 12 HCP and 24 ISCI participants: focus, rationale and approach. The salient components of the themes differed: HCPs focus on the physical causes of risks, and the ISCIs on their downstream consequences as well as on non-physical risks; HCPs are concerned about evidence, and ISCIs about experience; and HCPs approach risk narrowly, whereas the approach of ISCIs is more broad and contextualized.Conclusion:Although major themes were common to the two stakeholder groups, the components of the themes were dissociable and illustrate differences in what HCPs and ISCIs worry about, why they worry and how they approach their worries. We draw upon these findings to make recommendations for improving risk communication and informed consent for stem cell research for spinal cord injury. [ABSTRACT FROM AUTHOR]

We examine the effects of personal income tax progressivity-in the sense of rising marginal income tax rate-on self-employment. The impacts of income tax progressivity on self-employment depend on the relative effects of taxing success and the presence of tax evasion opportunities. Empirical estimates using Canadian provincial data for the period 1979-2006 indicate that there is a negative association between income tax progressivity and self-employment. This suggests that the adverse impact of income tax on entrepreneurial risk-taking outweighs the tax evasion opportunities for the self-employed. An important implication of our results is that a reduction in income tax progressivity encourages self-employment. The empirical estimates are robust to the various sensitivity checks. [ABSTRACT FROM AUTHOR]

Study design:Retrospective case series.Objectives:The objective of this study is to identify imaging and intraoperative characteristics that may predict surgical resection for myxopapillary ependymoma (MPE). The diffuse involvement in the conus-filum region makes complete resection challenging. The preoperative characteristics that may estimate the extent of resection has not been reported.Setting:Toronto, Canada.Methods:All MPE cases between 1972 and 2005 at a single institution were identified and reexamined by a neuropathologist. Neurological outcomes (Frankel scale), clinical features, operative findings, pre and postoperative imaging results were reviewed.Results:A total of 18 operations were performed on 15 MPE patients (8 females/7 males; age range: 18-71 years). Median postoperative follow-up was 56 months. Three patients (17%) developed tumor regrowth requiring reoperations. Preoperative magnetic resonance imaging (MRI; in 14/18 procedures) determined that tumors involved the conus in 70% of cases, which was significantly associated with intraoperative findings (P=0.02). Complete microsurgical resection was accomplished in 4 out of 7 cases where conus was not involved, but in only 1 out of 10 cases with conus involvement (P=0.056). The degree of conus involvement in one case was unclear. None of patients with total surgical resection developed recurrence. All patients survived at long-term follow-up.Conclusion:Our series is the first to correlate MPE involvement to conus medullaris on preoperative MRI with intraoperative findings, and examine its significance on surgical resectability. This information could guide clinicians in preoperative planning and advising patients on treatment options and potential risks/benefits. MRI is very sensitive (100%) and moderately specific (67%) in detecting direct anatomical contact between conus and MPE tumors. [ABSTRACT FROM AUTHOR]

Knowledge of the forces driving and modifying ecosystems can be employed in concert with signal analysis to target the data most likely to yield sensitivity and resilience information. One can optimize return of information per investment of resources by targeting segments of signals that are dominated by the force of interest, coupled with scientific understanding of the system of interest. This force analysis approach is an effective means both to design efficient new monitoring programs and to target relevant information in large data files. We present five example applications of force analysis. Three examples illustrate this approach for an evaluation of whether Canadian rivers might be sensitive to changes in climate. It was concluded that Canadian rivers appear to be sensitive to changing climate. A fourth example illustrates how automated snow pillow data may be evaluated to ascertain the sensitivity of snow accumulation to change in climate. It was concluded that snow accumulation at the site evaluated did appear to be sensitive to changing climate. The fifth example illustrates the assessment of whether a river recovers with the elimination of inputs of iron from an abandoned mine. It was concluded that resilience remained unproven since the river had not as yet restabilized. The force analysis approach focuses data collection or data evaluation on those data required to answer specific resource management questions, greatly reducing collection or consideration of data that are not relevant to that question. This approach is potentially very cost-efficient and therefore is likely to be of interest to hydrologists, climatologists, and environmental data managers. [ABSTRACT FROM AUTHOR]