Does Cognitive Status Modify the Relationship Between Education and Mortality? Evidence from the Canadian Study of Health and Aging

Background: There is compelling evidence of an inverse relationship between level of education and increased mortality. In contrast to this, one study showed that among subjects with Alzheimer's Disease, those with high education are more than twice as likely to die earlier; however, this result has proven difficult to replicate. We examine the relationship between education and mortality by cognitive status using a large, nationally representative sample of elderly. Methods: A representative sample of 10,263 people aged 65 or over from the 10 Canadian provinces participated in the Canadian Study of Health and Aging in 1991. Information about age, gender, education, and an initial screening for cognitive impairment were collected; those who screened positive for cognitive impairment were referred for a complete clinical and neuropsychological examination, from which cognitive status and clinical severity of dementia were assessed. Vital status and date of death were collected at follow-up in 1996. The analysis was conducted using survival analysis. Findings: Cognitive status modifies the relationship between education and mortality. For those with no cognitive impairment, an inverse relationship between education and mortality exists. Elderly with cognitive impairment but no dementia, or those with dementia, are more likely to die early than the cognitively normal at baseline, but no relationship exists between education and mortality. Interpretation: These findings do not support previous work that showed a higher risk of mortality among highly educated dementia subjects.Alzheimer disease; cognition; dementia; education; epidemiology; etiology; mortality

Accommodating quality and service improvement research within existing ethical principles

Funds were provided by a Canadian Institute of Health Research grant (Nominated PI: Monica Taljaard, PJT – 153045). Funds were also generously provided by Charles Weijer, who is funded by a Tier 1 Canadian Research Chair.Peer reviewedPublisher PD

Subarctic ecosystem resilience under changing disturbance regimes

Disturbance regimes are changing across the subarctic as a result of continued climate change. At the northern range edge of the boreal forest, changes to disturbance regimes are predicted to result in a shift in successional trajectory of the current plant community, altering the structure and function of the current ecosystem. As these boreal tree and shrub species are already climatically primed for range expansion, changes to disturbance regimes may facilitate increased establishment of boreal tree and shrub species beyond their current range edge. An investigation of how different disturbances influence biotic and abiotic conditions for early life-stages of boreal tree and shrub species was conducted at the Canadian boreal-tundra treeline ecotone to determine whether disturbances disrupt the ecological inertia of the current ecosystem, creating suitable conditions for successional change and northward boreal tree range expansion. Impacts to microsite conditions by wildfire, insect granivory on spruce cones, and anthropogenic wood harvesting were examined. These disturbance regimes were selected because they are anticipated to change in frequency and extent across the subarctic with continued climate change. Results from each investigation indicated that while disturbances did create conditions that could support increased establishment of boreal tree species, disturbance severities were low, often creating additional challenges for seed germination and establishment. Thus, disturbance induced changes to ecosystem structure and function are not anticipated at these research locations. Future research is required to examine disturbances of different severity at the range edge in order to determine whether disturbances of higher severity are likely to occur and whether they can break the ecological inertia of the current ecosystem

Patient information leaflets (PILs) for UK randomised controlled trials : a feasibility study exploring whether they contain information to support decision making about trial participation

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Decision aids for people considering taking part in clinical trials

The authors would like to thank the Cochrane Consumers and Communication Group editors and staff, in particular Sandy Oliver and John Kis‐Rigo, for their help and assistance with this review. We would also like to thank Cynthia Fraser, based at the Health Services Research Unit (University of Aberdeen), for help with development, refinement and running of the search strategies and Graeme MacLennan (also based at the Health Services Research Unit) for statistical advice. We would like to thank Muhammad Omar (Managing Editor of the Cochrane Incontinence Group) and Steven MacLennan (Academic Urology Unit, University of Aberdeen) for advice regarding RevMan and GRADE softwPeer reviewedPublisher PD

Inadequate reporting of research ethics review and informed consent in cluster randomized trials : review of random sample of published trials

Peer reviewedPublisher PD

Impact of CONSORT extension for cluster randomised trials on quality of reporting and study methodology : review of random sample of 300 trials, 2000-8

Peer reviewedPublisher PD

Can patient decision aids help people make good decisions about participating in clinical trials? A study protocol

<p>Abstract</p> <p>Background</p> <p>Evidence shows that the standard process for obtaining informed consent in clinical trials can be inadequate, with study participants frequently not understanding even basic information fundamental to giving informed consent. Patient decision aids are effective decision support tools originally designed to help patients make difficult treatment or screening decisions. We propose that incorporating decision aids into the informed consent process will improve the extent to which participants make decisions that are informed and consistent with their preferences. A mixed methods study will test this proposal.</p> <p>Methods</p> <p>Phase one of this project will involve assessment of a stratified random sample of 50 consent documents from recently completed investigator-initiated clinical trials, according to existing standards for supporting good decision making. Phase two will involve interviews of a purposive sample of 50 trial participants (10 participants from each of five different clinical areas) about their experience of the informed consent process, and how it could be improved. In phase three, we will convert consent forms for two completed clinical trials into decision aids and pilot test these new tools using a user-centered design approach, an iterative development process commonly employed in computer usability literature. In phase four, we will conduct a pilot observational study comparing the new tools to standard consent forms, with potential recruits to two hypothetical clinical trials. Outcomes will include knowledge of key aspects of the decision, knowledge of the probabilities of different outcomes, decisional conflict, the hypothetical participation decision, and qualitative impressions of the experience.</p> <p>Discussion</p> <p>This work will provide initial evidence about whether a patient decision aid can improve the informed consent process. The larger goal of this work is to examine whether study recruitment can be improved from (barely) informed consent based on disclosure-oriented documents, towards a process of high-quality participant decision-making.</p

Understanding the Canadian adult CT head rule trial: use of the theoretical domains framework for process evaluation

BACKGROUND: The Canadian CT Head Rule was prospectively derived and validated to assist clinicians with diagnostic decision-making regarding the use of computed tomography (CT) in adult patients with minor head injury. A recent intervention trial failed to demonstrate a decrease in the rate of head CTs following implementation of the rule in Canadian emergency departments. Yet, the same intervention, which included a one-hour educational session and reminders at the point of requisition, was successful in reducing cervical spine imaging rates in the same emergency departments. The reason for the varied effect of the intervention across these two behaviours is unclear. There is an increasing appreciation for the use of theory to conduct process evaluations to better understand how strategies are linked with outcomes in implementation trials. The Theoretical Domains Framework (TDF) has been used to explore health professional behaviour and to design behaviour change interventions but, to date, has not been used to guide a theory-based process evaluation. In this proof of concept study, we explored whether the TDF could be used to guide a retrospective process evaluation to better understand emergency physicians’ responses to the interventions employed in the Canadian CT Head Rule trial. METHODS: A semi-structured interview guide, based on the 12 domains from the TDF, was used to conduct telephone interviews with project leads and physician participants from the intervention sites in the Canadian CT Head Rule trial. Two reviewers independently coded the anonymised interview transcripts using the TDF as a coding framework. Relevant domains were identified by: the presence of conflicting beliefs within a domain; the frequency of beliefs; and the likely strength of the impact of a belief on the behaviour. RESULTS: Eight physicians from four of the intervention sites in the Canadian CT Head Rule trial participated in the interviews. Barriers likely to assist with understanding physicians’ responses to the intervention in the trial were identified in six of the theoretical domains: beliefs about consequences; beliefs about capabilities; behavioural regulation; memory, attention and decision processes; environmental context and resources; and social influences. Despite knowledge that the Canadian CT Head Rule was highly sensitive and reliable for identifying clinically important brain injuries and strong beliefs about the benefits for using the rule, a number of barriers were identified that may have prevented physicians from consistently applying the rule. CONCLUSION: This proof of concept study demonstrates the use of the TDF as a guiding framework to design a retrospective theory-based process evaluation. There is a need for further development and testing of methods for using the TDF to guide theory-based process evaluations running alongside behaviour change intervention trials