The Bayesian conditional independence model for measurement error: applications in ecology

The measurement error model is a well established statistical method for regression problems in medical sciences, although rarely used in ecological studies. While the situations in which it is appropriate may be less common in ecology, there are instances in which there may be benefits in its use for prediction and estimation of parameters of interest. We have chosen to explore this topic using a conditional independence model in a Bayesian framework using a Gibbs sampler, as this gives a great deal of flexibility, allowing us to analyse a number of different models without losing generality. Using simulations and two examples, we show how the conditional independence model can be used in ecology, and when it is appropriate.

Floods, earthquakes and insurance coverage : issues, problems and solutions

The recent floods in Queensland and elsewhere in Australia as well as the recent earthquakes in New Zealand have again given rise to very significant uninsured losses. This article looks at the issue of cover protection against catastrophes such as floods and earthquakes affecting home buildings and contents insurance and the standard cover provisions of the Insurance Contracts Act 1984 (Cth). It points also to the possibility of a national scheme to cover natural disasters including floods.

Year 7 students’ approaches to understanding and solving NAPLAN numeracy problems

This study investigated how the interpretation of mathematical problems by Year 7 students impacted on their ability to demonstrate what they can do in NAPLAN numeracy testing. In the study, mathematics is viewed as a culturally and socially determined system of signs and signifiers that establish the meaning, origins and importance of mathematics. The study hypothesises that students are unable to succeed in NAPLAN numeracy tests because they cannot interpret the questions, even though they may be able to perform the necessary calculations. To investigate this, the study applied contemporary theories of literacy to the context of mathematical problem solving. A case study design with multiple methods was used. The study used a correlation design to explore the connections between NAPLAN literacy and numeracy outcomes of 198 Year 7 students in a Queensland school. Additionally, qualitative methods provided a rich description of the effect of the various forms of NAPLAN numeracy questions on the success of ten Year 7 students in the same school. The study argues that there is a quantitative link between reading and numeracy. It illustrates that interpretation (literacy) errors are the most common error type in the selected NAPLAN questions, made by students of all abilities. In contrast, conceptual (mathematical) errors are less frequent amongst more capable students. This has important implications in preparing students for NAPLAN numeracy tests. The study concluded by recommending that increased focus on the literacies of mathematics would be effective in improving NAPLAN results.

The evidence-based development of an intervention to address the information needs of adults newly diagnosed with primary brain tumours and their carers

Adults diagnosed with primary brain tumours often experience physical, cognitive and neuropsychiatric impairments and decline in quality of life. Although disease and treatment-related information is commonly provided to cancer patients and carers, newly diagnosed brain tumour patients and their carers report unmet information needs. Few interventions have been designed or proven to address these information needs. Accordingly, a three-study research program, that incorporated both qualitative and quantitative research methods, was designed to: 1) identify and select an intervention to improve the provision of information, and meet the needs of patients with a brain tumour; 2) use an evidence-based approach to establish the content, language and format for the intervention; and 3) assess the acceptability of the intervention, and the feasibility of evaluation, with newly diagnosed brain tumour patients. Study 1: Structured concept mapping techniques were undertaken with 30 health professionals, who identified strategies or items for improving care, and rated each of 42 items for importance, feasibility, and the extent to which such care was provided. Participants also provided data to interpret the relationship between items, which were translated into ‘maps’ of relationships between information and other aspects of health care using multidimensional scaling and hierarchical cluster analysis. Results were discussed by participants in small groups and individual interviews to understand the ratings, and facilitators and barriers to implementation. A care coordinator was rated as the most important strategy by health professionals. Two items directly related to information provision were also seen as highly important: "information to enable the patient or carer to ask questions" and "for doctors to encourage patients to ask questions". Qualitative analyses revealed that information provision was individualised, depending on patients’ information needs and preferences, demographic variables and distress, the characteristics of health professionals who provide information, the relationship between the individual patient and health professional, and influenced by the fragmented nature of the health care system. Based on quantitative and qualitative findings, a brain tumour specific question prompt list (QPL) was chosen for development and feasibility testing. A QPL consists of a list of questions that patients and carers may want to ask their doctors. It is designed to encourage the asking of questions in the medical consultation, allowing patients to control the content, and amount of information provided by health professionals. Study 2: The initial structure and content of the brain tumour specific QPL developed was based upon thematic analyses of 1) patient materials for brain tumour patients, 2) QPLs designed for other patient populations, and 3) clinical practice guidelines for the psychosocial care of glioma patients. An iterative process of review and refinement of content was undertaken via telephone interviews with a convenience sample of 18 patients and/or carers. Successive drafts of QPLs were sent to patients and carers and changes made until no new topics or suggestions arose in four successive interviews (saturation). Once QPL content was established, readability analyses and redrafting were conducted to achieve a sixth-grade reading level. The draft QPL was also reviewed by eight health professionals, and shortened and modified based on their feedback. Professional design of the QPL was conducted and sent to patients and carers for further review. The final QPL contained questions in seven colour-coded sections: 1) diagnosis; 2) prognosis; 3) symptoms and problems; 4) treatment; 5) support; 6) after treatment finishes; and 7) the health professional team. Study 3: A feasibility study was conducted to determine the acceptability of the QPL and the appropriateness of methods, to inform a potential future randomised trial to evaluate its effectiveness. A pre-test post-test design was used with a nonrandomised control group. The control group was provided with ‘standard information’, the intervention group with ‘standard information’ plus the QPL. The primary outcome measure was acceptability of the QPL to participants. Twenty patients from four hospitals were recruited a median of 1 month (range 0-46 months) after diagnosis, and 17 completed baseline and follow-up interviews. Six participants would have preferred to receive the information booklet (standard information or QPL) at a different time, most commonly at diagnosis. Seven participants reported on the acceptability of the QPL: all said that the QPL was helpful, and that it contained questions that were useful to them; six said it made it easier to ask questions. Compared with control group participants’ ratings of ‘standard information’, QPL group participants’ views of the QPL were more positive; the QPL had been read more times, was less likely to be reported as ‘overwhelming’ to read, and was more likely to prompt participants to ask questions of their health professionals. The results from the three studies of this research program add to the body of literature on information provision for brain tumour patients. Together, these studies suggest that a QPL may be appropriate for the neuro-oncology setting and acceptable to patients. The QPL aims to assist patients to express their information needs, enabling health professionals to better provide the type and amount of information that patients need to prepare for treatment and the future. This may help health professionals meet the challenge of giving patients sufficient information, without providing ‘too much’ or ‘unnecessary’ information, or taking away hope. Future studies with rigorous designs are now needed to determine the effectiveness of the QPL.

Managing medical advice seeking in calls to Child Health Line

Child Health Line is a 24-hour Australian helpline that offers information and support for parents and families on child development and parenting. The helpline guidelines suggest that nurses should not offer medical advice, however they regularly receive calls seeking such advice. This paper examines how the service guidelines are talked into being through the nurses’ management of caller’s requests for medical advice and information, and shows how nurses orient to the boundaries of their professional role and institutionally regulated authority. Three ways in which the child health nurses manage medical advice and information seeking are discussed: using membership as a nurse to establish boundaries of expertise, privileging parental authority regarding decision making about seeking treatment for their child, and respecifying a ‘medical’ problem as a child development issue. The paper contributes to research on medical authority, and nurse authority in particular, by demonstrating the impact of institutional roles and guidelines on displays of knowledge and expertise. More generally, it contributes to an understanding of the interactional enactment and consequences of service guidelines for telehealth practice, with implications for training, policy and service delivery.

Defences in medical negligence : to what extent has tort law reform in Australia limited the liability of health professionals?

Tort law reform has resulted in legislation being passed by all Australian jurisdictions in the past decade implementing the recommendations contained in the Ipp Report. The report was in response to a perceived crisis in medical indemnity insurance. The objective was to restrict and limit liability in negligence actions. This paper will consider to what extent the reforms have impacted on the liability of health professionals in medical negligence actions. The reversal of the onus of proof through the obvious risk sections has attempted to extend the scope of the defence of voluntary assumption of risk. There is no liability for the materialisation of an inherent risk. Presumptions and mandatory reductions for contributory negligence have attempted to reduce the liability of defendants. It is now possible for reductions of 100% for contributory negligence. Apologies can be made with no admission of legal liability to encourage them being made and thereby reduce the number of actions being commenced. The peer acceptance defence has been introduced and enacted by legislation. There is protection for good samaritans even though the Ipp Report recommended against such protection. Limitation periods have been amended. Provisions relating to mental harm have been introduced re-instating the requirement of normal fortitude and direct perception. After an analysis of the legislation, it will be argued in this paper that while there has been some limitation and restriction, courts have generally interpreted the civil liability reforms in compliance with the common law. It has been the impact of statutory limits on the assessment of damages which has limited the liability of health professionals in medical negligence actions.

Loss of chance in medical negligence claims now a lost cause?

The question whether the loss of chance of a better medical outcome in cases of medical negligence should be recognised as actionable damage is ‘a question which has divided courts and commentators throughout the common law world.’ In April 2010, the High Court handed down its anticipated decision in the case of Tabet (by her Tutor Sheiban) v Gett (2010) 240 CLR 537. The issue considered by the court was whether the appellant could claim in negligence for the loss of a chance of a better medical outcome. This issue had not been considered by the High Court previously, the most relevant cases being Rufo v Hosking (2004) 61 NSWLR 678 and Gavalas v Singh (2001) 3 VLR 404. Claiming for a loss of chance in a personal injury action raises questions as to recognised damage and causation, and the members of the High Court considered both of these.

A node-based smoothed conforming point interpolation method (NS-CPIM) for elasticity problems

This paper formulates a node-based smoothed conforming point interpolation method (NS-CPIM) for solid mechanics. In the proposed NS-CPIM, the higher order conforming PIM shape functions (CPIM) have been constructed to produce a continuous and piecewise quadratic displacement field over the whole problem domain, whereby the smoothed strain field was obtained through smoothing operation over each smoothing domain associated with domain nodes. The smoothed Galerkin weak form was then developed to create the discretized system equations. Numerical studies have demonstrated the following good properties: NS-CPIM (1) can pass both standard and quadratic patch test; (2) provides an upper bound of strain energy; (3) avoid the volumetric locking; (4) provides the higher accuracy than those in the node-based smoothed schemes of the original PIMs.

Re-thinking how we plan to address technically complex problems : drawing on planning theory to guide practice in revision of land use plans in coastal high hazard zones

Queensland's new State Planning Policy for Coastal Protection, released in March and approved in April 2011 as part of the Queensland Coastal Plan, stipulates that local governments prepare and implement adaptation strategies for built up areas projected to be subject to coastal hazards between present day and 2100. Urban localities within the delineated coastal high hazard zone (as determined by models incorporating a 0.8 meter rise in sea level and a 10% increase in the maximum cyclone activity) will be required to re-evaluate their plans to accommodate growth, revising land use plans to minimise impacts of anticipated erosion and flooding on developed areas and infrastructure. While implementation of such strategies would aid in avoidance or minimisation of risk exposure, communities are likely to face significant challenges in such implementation, especially as development in Queensland is so intensely focussed upon its coasts with these new policies directing development away from highly desirable waterfront land. This paper examines models of planning theory to understand how we plan when faced with technically complex problems towards formulation of a framework for evaluating and improving practice.

Advance directives, autonomy and the refusal of life-sustaining medical treatment

As Australian society 1s agemg, individuals are increasingly concerned about managing their future, including making decisions about the medical treatment they may wish to receive or refuse if they lose decision-making capacity. To date, there has been relatively little research into the extent to which legal regulation allows competent adults to make advance refusals of life-sustaining medical treatment that will bind health professionals and others when a decision needs to be made at a future time. This thesis aims to fill this gap in the research by presenting the results of research into the legal regulation of advance directives that refuse life-sustaining medical treatment. In the five papers that comprise this thesis, the law that governs this area is examined, and the ethical principle of autonomy is used to critically evaluate that law. The principal finding of this research is that the current scheme of regulation is ineffective to adequately promote the right of a competent adult to make binding advance directives about refusal of medical treatment. The research concludes that legislation should be enacted to enable individuals to complete an advance directive, only imposing restrictions to the extent that this is necessary to promote individual autonomy. The thesis first examines the principle of autonomy upon which the common law (and some statutory law) is expressed to be based, to determine whether that principle is an appropriate one to underpin regulation. 1 The finding of the research is that autonomy can be justified as an organising principle on a number of grounds: it is consistent with the values of a liberal democracy; over recent decades, it is a principle that has been even more prominent within the discipline of medical ethics; and it is the principle which underpins the legal regulation of a related topic, namely the contemporaneous refusal of medical treatment. Next, the thesis reviews the common law to determine whether it effectively achieves the goal of promoting autonomy by allowing a competent adult to make an advance directive refusing treatment that will operate if he or she later loses decision-making capacity. 2 This research finds that conunon law doctrine, as espoused by the judiciary, prioritises individual choice by recognising valid advance directives that refuse treatment as binding. However, the research also concludes that the common law, as applied by the judiciary in some cases, may not be effective to promote individual autonomy, as there have been a number of circumstances where advance directives that refuse treatment have not been followed. The thesis then examines the statutory regimes in Australia that regulate advance directives, with a focus on the regulation of advance refusals of life-sustaining medical treatment.3 This review commences with an examination ofparliamentary debates to establish why legislation was thought to be necessary. It then provides a detailed review of all of the statutory regimes, the extent to which the legislation regulates the form of advance directives, and the circumstances in which they can be completed, will operate and can be ignored by medical professionals. The research finds that legislation was enacted mainly to clarify the common law and bring a level of certainty to the field. Legislative regimes were thought to provide medical professionals with the assurance that compliance with an advance directive that refuses life-sustaining medical treatment will not expose them to legal sanction. However, the research also finds that the legislation places so many restrictions on when an advance directive refusing treatment can be made, or will operate, that they have not been successful in promoting individual autonomy.

Refusal of medical treatment : a child's prerogative?

Society has a need for children to be able to make health care decisions. Homeless children need access to health care. Parents may not be accessible or competent to consent to their child’s health care. The familial relationship may have broken down. Children may not want their parents to know about drug, alcohol or pregnancy related issues. There is legal and academic support for the right of children to make autonomous decisions with respect to their health care. However what these decisions cover and who can make them is not clear. Whether or not a minor has capacity and is therefore competent to consent to medical treatment is a question of law. Some states of Australia have enacted legislation, while others rely on the common law to determine this issue. At common law a minor is capable of giving consent to medical treatment when he or she achieves a sufficient understanding and intelligence to be able to understand fully what is proposed. Known as ‘Gillick competence’ this is a well known principle of law. The question posed by this paper is whether the decision of a ‘Gillick competent’ child can and should be overridden by the court?

Problems with a great idea : referral by prehospital emergency services to a community-based falls-prevention service

Background and aim Falls are the leading cause of injury in older adults. Identifying people at risk before they experience a serious fall requiring hospitalisation allows an opportunity to intervene earlier and potentially reduce further falls and subsequent healthcare costs. The purpose of this project was to develop a referral pathway to a community falls-prevention team for older people who had experienced a fall attended by a paramedic service and who were not transported to hospital. It was also hypothesised that providing intervention to this group of clients would reduce future falls-related ambulance call-outs, emergency department presentations and hospital admissions. Methods An education package, referral pathway and follow-up procedures were developed. Both services had regular meetings, and work shadowing with the paramedics was also trialled to encourage more referrals. A range of demographic and other outcome measures were collected to compare people referred through the paramedic pathway and through traditional pathways. Results Internal data from the Queensland Ambulance Service indicated that there were approximately six falls per week by community-dwelling older persons in the eligible service catchment area (south west Brisbane metropolitan area) who were attended to by Queensland Ambulance Service paramedics, but not transported to hospital during the 2-year study period (2008–2009). Of the potential 638 eligible patients, only 17 (2.6%) were referred for a falls assessment. Conclusion Although this pilot programme had support from all levels of management as well as from the service providers, it did not translate into actual referrals. Several explanations are provided for these preliminary findings.

Wound problems following hip arthroplasty before and after the introduction of a direct thrombin inhibitor for thromboprophylaxis

NICE guidelines have stated that patients undergoing elective hip surgery are at increased risk for venous thromboembolic events (VTE) following surgery and have recommended thromboprophylaxis for 28-35 days1, 2. However the studies looking at the new direct thrombin inhibitors have only looked at major bleeding. We prospectively looked at wound discharge in patients who underwent hip arthroplasty and were given dabigatran postoperatively between March 2010 and April 2010 (n=56). We retrospectively compared these results to a matched group of patients who underwent similar operations six months earlier when all patients were given dalteparin routinely postoperatively until discharge, and discharged home on 150mg aspirin daily for 6 weeks (n=67). Wound discharge after 5 days was significantly higher in the patients taking dabigatran (32% dabigatran n=18, 10% dalteparin n=17, p=0.003) and our rate of delayed discharges due to wound discharge significantly increased from 7% in the dalteparin group (n=5) to 27% for dabigatran (n=15, p=0.004). Patients who received dabigatran were more than five times as likely to return to theatre with a wound complication as those who received dalteparin (7% dabigatran n=4, vs. 1% dalteparin n=1), however, this was not statistically significant (p=0.18). The significantly higher wound discharge and return to theatre rates demonstrated in this study have meant that we have changed our practice to administering dalteparin until the wound is dry and then starting dabigatran. Our study demonstrates the need for further clinical studies regarding wound discharge and dabigatran.

A prospective cohort study of geriatric syndromes among older medical patients admitted to acute care hospitals

OBJECTIVES: To identify the prevalence of geriatric syndromes in the premorbid for all syndromes except falls (preadmission), admission, and discharge assessment periods and the incidence of new and significant worsening of existing syndromes at admission and discharge. DESIGN: Prospective cohort study. SETTING: Three acute care hospitals in Brisbane, Australia. PARTICIPANTS: Five hundred seventy-seven general medical patients aged 70 and older admitted to the hospital. MEASUREMENTS: Prevalence of syndromes in the premorbid (or preadmission for falls), admission, and discharge periods; incidence of new syndromes at admission and discharge; and significant worsening of existing syndromes at admission and discharge. RESULTS: The most frequently reported premorbid syndromes were bladder incontinence (44%), impairment in any activity of daily living (ADL) (42%). A high proportion (42%) experienced at least one fall in the 90 days before admission. Two-thirds of the participants experienced between one and five syndromes (cognitive impairment, dependence in any ADL item, bladder and bowel incontinence, pressure ulcer) before, at admission, and at discharge. A majority experienced one or two syndromes during the premorbid (49.4%), admission (57.0%), or discharge (49.0%) assessment period.The syndromes with a higher incidence of significant worsening at discharge (out of the proportion with the syndrome present premorbidly) were ADL limitation (33%), cognitive impairment (9%), and bladder incontinence (8%). Of the syndromes examined at discharge, a higher proportion of patients experienced the following new syndromes at discharge (absent premorbidly): ADL limitation (22%); and bladder incontinence (13%). CONCLUSION: Geriatric syndromes were highly prevalent. Many patients did not return to their premorbid function and acquired new syndromes.