Statistics

To the Editor: We read with interest the report by Sitas and colleagues about the Australian Broadcasting Corporation (ABC) breast cancer cluster investigation.1 After publication of the final report on the ABC cancer cluster,2 the Public Health Unit of Sydney South West Area Health Service undertook a similar investigation. In May 2007, our Public Health Unit was contacted by an occupational health representative after reports of five recent cases of breast cancer among women working in two departments at a Sydney hospital between 2002 and 2006. Four of these cases were confirmed, and all four women had offices in the same area of the hospital. Based on the assumption that women employed in these two departments between 2001 and 2006 (a total of 69 women) were the population “at risk”, we found that there was an excess of observed cases over expected cases (standardised incidence ratio [SIR], 15.1 [95% CI, 4.1–38.8]; P < 0.001). There were no known hazards affecting these women that would not be present elsewhere in the hospital, so an expert panel recommended a hospital-wide epidemiological investigation and environmental survey. The case definition was any woman diagnosed with invasive breast cancer while working at the hospital between 1 January 1998 and 31 August 2007. To ascertain cases, we wrote a letter to all current employees and issued a media release. A dedicated telephone hotline received 147 calls from 19 July to 31 August 2007. We confirmed 24 cases meeting the case definition. These women had a mean age of 51 years at diagnosis, had worked at the hospital for a median of 11 years, were not clustered by work location or type, and had similar risk factors for developing breast cancer to women in the New South Wales population as a whole. From employment records and NSW cancer statistics, we calculated that 23 cases of invasive breast cancer would be expected based on the age structure and size of the female workforce at the hospital over the study period. The observed number of cases was not significantly different from the expected number (SIR, 1.1 [95% CI, 0.7–1.6]; P = 0.44).3 In the environmental survey, no unusual hazards were identified. Breast cancer is the most common invasive cancer diagnosed in Australian women.4 In most cases, potential “clusters” are probably a chance occurrence, even when the number of cases is statistically significantly higher than expected, with no plausible explanation identified.5 Our investigation found no excess of cases of breast cancer in women employed at the hospital over the study period. Guidelines6 are helpful in defining a consistent approach to cluster investigation, but such investigations are resource intensive. Careful initial analysis of information is important to determine whether further investigation of a reported cluster is warranted. In our study, we concluded that a broader investigation was justified.

Catherine Francis · Trish F Mannes · Leena Gupta · Stephen J Conaty

Objective: To compare trends in invasive pneumococcal disease (IPD) in non-Indigenous people in north Queensland before and after the introduction of funded pneumococcal vaccines, and to examine the proportion of cases that occurred after vaccine roll-out that could be vaccine-preventable.Design, setting and participants: In 2005, a 7-valent pneumococcal conjugate vaccine (7vPCV) for non-Indigenous children and a 23-valent pneumococcal polysaccharide vaccine (23vPPV) for non-Indigenous adults aged ≥ 65 years were made freely available. Trends in IPD in the non-Indigenous estimated resident population in north Queensland (about 581 850 in 2006) were compared between the 4 years before (2001–2004) and after (2006–2009) the vaccines were rolled out.Main outcome measures: Incidences and serotypes of IPD in non-Indigenous people.Results: After the introduction of the vaccines, there were significant declines for all ages in the average annual incidence of IPD (− 34%; P < 0.05) and 7vPCV serotype IPD (− 77%; P < 0.05). In children aged < 5 years, there was a 91% decline in the incidence of 7vPCV serotype IPD (P < 0.05); in adults aged 15–64 years and ≥ 65 years there were 62% and 77% declines, respectively, in 7vPCV and 23vPPV common-serotype IPD (P < 0.05). There was a 188% increase in 23vPPV-only serotype IPD in adults aged 15–64 years (P < 0.05), whereas there was no significant change in adults aged ≥ 65 years. Serotype 19A was the most frequently identified serotype in 2006–2009, causing 19% of all IPD in those 4 years.Conclusions: There is circumstantial evidence that 7vPCV has had a powerful indirect effect in preventing IPD in adults in north Queensland; 23vPPV may have had a direct effect in adults aged ≥ 65 years. It is likely that with combined direct and indirect effects, newer conjugate vaccines could prevent more IPD than could be prevented with the two current vaccines.

Jeffrey N Hanna MPH, FAFPHM · Jan L Humphreys RN · Denise M Murphy DipMedTech · Helen V Smith GradDipPH, BApplSci, MASM

Objective: Design, setting and participants: Vaccination data for Western Australians aged 10 years and older were obtained from two sources: the WA Pandemic Influenza Vaccination Database (PIVD; which collected reports of pandemic influenza vaccinations from vaccination providers statewide) for the period 30 September 2009 to 31 January 2010, and the WA Health and Wellbeing Surveillance System (HWSS; a continuous population-based telephone survey) for the period 1 December 2009 to 31 January 2010. Data from the PIVD was used to impute vaccination coverage estimates for at-risk subpopulations not assessed in the HWSS interviews.Main outcome measures: Vaccination coverage of Western Australians aged 10 years and older and of subgroups targeted by the national pandemic (H1N1) 2009 influenza vaccination campaign.Results: A total of 171 789 pandemic influenza vaccinations were reported to the PIVD by 31 January 2010 and 88% of these were administered by 1 December 2009. Based on HWSS data, vaccination coverage of persons aged 10 years and older was 14.5% (95% CI, 12.6%–16.6%) and of persons aged 18 years and older was 15.3% (95% CI, 13.3%–17.6%). Based on PIVD data, coverage in adults ranged from 10.3% in pregnant women to 52.8% in health care workers.Conclusions: Our estimate of pandemic influenza vaccination coverage in the adult population of WA is comparable to the national estimate of 19%, but it did not reach levels considered sufficient to interrupt community transmission. Future influenza vaccination programs should target groups at increased risk of severe influenza, such as pregnant women.

Donna B Mak MB BS, MPH, FAFPHM · Alison M Daly BA(Hons), BA(Ed) · Paul K Armstrong MBBS, MAE, FRACP · Paul V Effler MD, MPH, FAFPHM

Objective: Design, setting and participants: Cross-sectional study of consecutive patients attending the Joondalup Health Campus public antenatal clinics in WA in January 2010.Intervention: Audit of uptake of the H1N1-specific vaccine.Main outcome measures: Rate of H1N1-specific vaccination, and reasons for not being the vaccinated.Results: 479 of 541 women who attended the clinics (88.5%) were included in the audit. Three women had been infected with pandemic influenza in the preceding influenza season, leaving 476 women who were eligible for vaccination in pregnancy. Of these 476 women, only 33 (6.9%) had been vaccinated. Of the remaining 443 women who were eligible to receive the vaccine but had not been vaccinated, 63.9% had not been offered vaccination despite multiple visits to their general practitioners during pregnancy, 19.6% had been advised by their GPs against vaccination in pregnancy, and 61.6% stated that they would decline vaccination if offered because of safety concerns.Conclusions: Uptake of H1N1-specific influenza vaccine in pregnant women was poor. Reasons for this relate both to vaccination not being offered to or actively sought by the women, as well as concerns — of both the women and their GPs — about vaccine safety in pregnancy. Uptake in this setting may improve if vaccination is offered through public antenatal clinics with concurrent safety education for obstetricians and vaccination providers.

Scott W White MB BS · Rodney W Petersen MB BS, MBA, FRANZCOG · Julie A Quinlivan MB BS, PhD, FRANZCOG

Objective: To evaluate whether systematic asthma care involving a register-recall system, postcard prompts for review, and education for general practitioners and staff in Australian general practice improves the quality of care and health outcomes for adult patients with moderate to severe asthma.Design and setting: Cluster randomised controlled trial in 40 general practices in urban and rural South Australia and New South Wales over the 2 years 2004 and 2005; practices were randomly allocated to the intervention or control group.Participants: 565 adult patients of these randomly allocated practices who had doctor-diagnosed moderate to severe asthma and were taking inhaled corticosteroids.Main outcome measures: Clinical asthma indicators, quality of care, acceptability of the intervention to patients, quality of life, and asthma self-management skills at baseline, 6 months and 12 months.Results: Although 46% of patients in the intervention group practices responded to the postcard prompts, only 32% actually attended for their asthma review. At 12 months, there was a statistically significant difference in provision of written asthma action plans (rate ratio, 1.9; 95% CI, 1.0–3.5; P = 0.04) for intervention group patients compared with control group patients; there was no significant difference in other indicators.Conclusion: We found little objective evidence of improvement in patient management and outcomes resulting from a systematic model of asthma care.Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12605000091606

Christine H Holton GDAcc, GDPH, CPA · Justin J Beilby MD, MPH, FRACGP · Mark F Harris MB BS, MD, FRACGP · Clare E Harper BSc(Hons), MMedSci(Human Nutr) · Judith G Proudfoot GradDipSpEd, MA(Psych), PhD · Emmae N Ramsay BSc(Ma · Richard E Ruffin MD, FRACP, AM

Objectives: To assess whether a collaborative interdepartmental pathway involving emergency department (ED) physicians activating the cardiac catheterisation laboratory (CCL) with immediate patient transfer to the CCL reduces door-to-balloon (DTB) times for patients with suspected ST-elevation myocardial infarction (STEMI).Design, setting and participants: A quasi-experimental before-and-after observational study using a prospective database, supplemented by chart review, of consecutive patients transferred from the ED to the CCL for suspected STEMI, from January 2007 to October 2009, at Sir Charles Gairdner Hospital, an adult tertiary-care hospital, Western Australia.Main outcomes measures: Median DTB time and proportion of patients with DTB time of < 90 minutes. Secondary outcomes, based on analysis of predefined subgroups, included door-to-activation time, activation-to-balloon time and false-positive activations of the CCL.Results: Two hundred and thirty-four patients underwent emergency coronary angiography for suspected STEMI, with 188 (80%) undergoing percutaneous coronary intervention (118 before and 70 after implementation of the new pathway). Following implementation of the new pathway, median DTB time reduced from 97 to 77 minutes (P < 0.001), median door-to-activation time from 28 to 15 minutes (P = 0.002) and median activation-to-balloon time from 66 to 53 minutes (P < 0.001). The proportion of patients with recommended DTB time of < 90 minutes increased from 41% to 77% (P < 0.001) with no change in false positive CCL activation rates (12% v 11%; P = 0.38).Conclusion: ED physician activation of CCL with immediate patient transfer is associated with highly significant improvements in DTB time without increased false positive rates.

Alexander B Willson MB BS(Hons), MPH, FRACP · David Mountain MB BS, FACEM · Joanne M Jeffers MB BS · Cheryl G Blanton MSc · Brendan M McQuillan MB BS, PhD, FRACP · Joseph Hung MB BS, FRACP, FCSANZ · Michael H Muhlmann MB BS, FRACP · Michael C Nguyen MB BS, FRACP

Evidence-based practice. Across the health professions. Tammy Hoffman, Sally Bennett, Chris Del Mar, editors. Sydney: Churchill Livingstone, 2009 (xiv + 349 pp). ISBN 9780729539029. Putting evidence into practice is a challenge for all health professionals; not just knowing the evidence, but being able to interpret it and put it into practice in the face of a range of barriers and constraints. The editors of this book are specialists in evidenced-based practice and have led classes in the subject for students from a range of health professions. Tammy Hoffman and Sally Bennett are both lecturers at University of Queensland’s School of Health and Rehabilitation Sciences, while Chris Del Mar is Professor of Primary Care Research at Bond University and a Coordinating Editor of the international Cochrane Collaboration. Contributors include experts from Australia and overseas, who provide a wealth of examples on how evidence-based clinical decisions are made by different health professionals. The book takes the reader from formulating the question to finding and evaluating the evidence required to answer it. This is not for the faint-hearted — the various chapters describe in detail how to appraise the validity (and bias) of intervention trials and how to interpret the significance of their findings. It may be pretty heavy going for many clinicians. However, the book then goes on to work through examples encountered by different health professionals in a wide variety of real-life clinical settings. For example, the questions about the efficacy of interventions range from cognitive behavioural interventions by practice nurses to adjuvant temozolomide with radiation therapy for glioblastoma. Most of the chapters focus on appraising individual studies. This is a good way to illustrate the use of appraisal skills and avoids the risk of providing simplistic answers to clinical questions. However, much of routine practice may be more appropriately informed by systematic reviews of the literature (such as Cochrane reviews) and systematically developed evidence-based guidelines. These are covered in Chapters 12 and 13, but without the in-depth case study analysis used in the earlier chapters. This is a little disappointing. Despite these reservations, I found this to be a surprisingly readable and thorough introduction to the appraisal of evidence for multidisciplinary clinical practice.

Mark F Harris

It may be time to invest more in primary care research, including research on clinical conditions Here is a simple exercise: in the PubMed website (http://www.ncbi.nlm.nih.gov/pubmed), type “The New England Journal of Medicine[Jour] AND Australia[All Fields]”, and you will see that the journal has published about 90 Australian articles since 2000. Scanning through them, you will find that just one includes an Australian general practitioner as an author (Professor John Marley, in 10th author position), for an article describing the large blood pressure trial ANBP2.1 Repeating this exercise for JAMA (the journal of the American Medical Association) yields one Australian GP author in one of 79 Australian papers (Professor Chris Silagy as first author), in an analysis of protocols of published systematic reviews and reports.2 But what should we expect in the way of research from just one discipline — general practice — in one country? Should we conclude that general practice is not a glittering performer among the medical and health disciplines in Australia, or that it is holding its own? On one hand, it could be argued that general practice is not likely to be the area for such revolutionary discoveries as will command attention from the two most-cited medical journals. We could, instead, think of general practice as the final common pathway for best practice, honed in specialty clinical practice and research. On the other hand, general practice could be described as not only an obvious but perhaps even an indispensable place for research in the areas of health services (ways of delivering care better) and clinical research into diseases encountered in primary care. It may even be a place for basic science research. General practice is where about three-quarters of all medical consultations in Australia take place. The gaps between practice and the best evidence are as wide there as anywhere, and our need for information is urgent.3 On the basis of the numbers of clinicians in the discipline who need information, primary care research output should be the highest compared with the other (smaller) disciplines. But this was not the case a decade ago and is still not the case today, although the situation has improved. A 2001 study, using clinician numbers in the discipline as a denominator, showed that research in the area of internal medicine and surgery in Australia was 60–100 times more productive than that of general practice.4 In addition, general practice research is usually published in journals that are considerably less cited than specialty journals (although a citation index is an imperfect way of measuring research quality).5 The stimulus for a surge in Australian primary care research came from an unexpected quarter. In 1989, the proposal to form a register of GPs, championed by the Royal Australian College of General Practitioners (RACGP), was met with opposition from some non-RACGP-aligned GPs and the Australian Medical Association. The Australian Government referred this political hot potato to the Senate Select Committee on Health Legislation and Health Insurance, which took submissions around the country.6 The Committee noted that little information was available about Australian general practice, and made two recommendations. One recommendation approved the proposed GP register (registration then requiring vocational GP training); the other was for a program of evaluative research to be established, the General Practice Evaluation Program (GPEP).7 This was the predecessor of the current Primary Health Care Research Evaluation and Development (PHCRED) program and, between them, these programs have since been the major sources of funding for Australian general practice research.8,9 Early general practice research was over-reliant on surveys and descriptive studies.7 Intervention studies started soon afterwards, although they were bemoaned as still too few and insufficiently rigorous.10 The subject matter for research has been heavily biased towards health services research at the expense of clinical illnesses, as might be expected from the historical origins of the funding.11 The investment has certainly paid off, lifting the average from one to three publications per 1000 Australian GPs per year over the past decade, with physicians now being “only” 50 times more productive than GPs.12 Primary care research has been criticised for being too “soft” (using qualitative rather than quantitative methods), and it may be true that too many nascent researchers think that qualitative research, or even survey research, will be easier than quantitative research; neither is. However, this is to confuse the mode of research with its purpose, that is, to answer the type of question that is being asked. One must use the right tools for the job. For example, questions about interventions need randomised trials; questions about diagnosis need consecutively enrolled cohort studies; and questions about aetiology need case–control studies. But sometimes a question, particularly in relation to implementation of multistranded interventions, can only be answered by using several methods — “mixed methods” research — to allow for some of the complexities of primary care.13 More important is the question of what to research. It may be time to invest more in primary care research on clinical conditions (Box). There is more uncertainty about clinical conditions managed in primary care than about many conditions managed by specialists, and there is much research to conduct. A useful leaf that we, as GP researchers, should take from the specialists’ book is to work more collaboratively with basic science researchers. A good example of a successful collaboration of this sort is a study about the prevalence of whooping cough in children, which has changed the way we think about persistent cough after apparently trivial acute respiratory infections — might it be due to pertussis? In this study, bench-top scientists worked with GP researchers to generate a rapid and reliable diagnostic test for infection with Bordetella pertussis.15 Now is the time for more investment in primary care research — of any kind. Australian primary care research funding 2000–2010: clinical research items compared with total items14 Funding body Total items funded Clinical research items funded Primary Health Care Research Evaluation and Development* 46 0 National Health and Medical Research Council 166 27 Pharmacy Guild 82 0 Total 294 27 * Since 2003.

Christopher B Del Mar MB BChir, FRACGP, MD · Mieke L van Driel MD, PhD

Objectives: To assess whether the management rate of herpes zoster (HZ) in Australian general practice has changed since varicella vaccines became available; and to ascertain the mean age of patients attending general practice for HZ management, to assist with planning of vaccination to prevent HZ in older Australians.Design, setting and participants: Retrospective analysis of data for the period April 1998 to March 2009 on 1 078 671 (weighted) management encounters with consecutive patients of 10 885 general practitioners who participated in the BEACH (Bettering the Evaluation and Care of Health) national cross-sectional survey.Main outcome measures: Number of encounters for management of HZ (shingles) and of varicella (chickenpox); age of patients presenting for HZ management.Results: Regression analysis indicated a significant rise in the HZ management rate over the study period, with an average annual increase of 0.05 per 1000 encounters (P < 0.01). The management rate for varicella decreased significantly from 2.01 per 1000 encounters in 1998–1999 to 0.58 per 1000 in 2008–2009. Mean age calculated for each year of the study varied between 10.2 and 15.3 years for patients with varicella, and between 57.5 and 64.1 years for patients with HZ.Conclusions: There has been a significant rise in the HZ management rate and a decrease in the varicella management rate in Australian general practice over the period 1998–2009. Introduction of vaccination for HZ prevention at age 60 years should be considered, although addition of this vaccination to the existing schedule for vaccination at age 65 years is also likely to be beneficial and may be more pragmatic.

Mark R Nelson FRACGP, FAFPHM, PhD · Helena C Britt BA, PhD · Christopher M Harrison BPsych(Hons), MSocHlth

Objectives: To assess the prevalence of and risk factors for claudication and its association with subsequent cardiovascular events.Design, setting and participants: Observational cohort study of 12 203 Western Australian men aged 65 years and over, recruited from 1996 to 1999, and followed up from 2001 to 2004.Main outcome measures: Prevalence of claudication and incidence of peripheral arterial disease (PAD); risk factors for claudication and its association with subsequent cardiovascular events.Results: The prevalence of claudication was 5.3% (638 of 11 970 men). At follow-up, after exclusion of 148 men with claudication at baseline and 76 with missing data at follow-up, the crude average annual incidence of new PAD (claudication or procedure for PAD) was 0.85% (95% CI, 0.72%–0.96%). The risk factors for prevalent claudication and incident PAD were similar, with age, smoking, hypertension, diabetes and history of cardiovascular disease dominating. Of the men with claudication at baseline, nearly half (47.5%; 303 of 638) were not taking aspirin. At follow-up, 42.5% (82 of 193) of the men with incident PAD were not taking aspirin. Claudication at baseline was associated with twice the risk of cardiovascular death (hazard ratio, 2.00; 95% CI, 1.52–2.64). There was a J-shaped relationship between aortic diameter, and both prevalent claudication and subsequent cardiovascular events.Conclusions: Among older men, claudication is prevalent and is associated with factors that can still be modified in older age, including smoking, exercise and diet. Relatively few men with claudication or at risk of PAD use aspirin. Claudication is a significant predictor of cardiovascular outcome.

Rahul Lakshmanan MB BS · Zoë Hyde BSc, PGradDipHlthProm, MPH · Konrad Jamrozik MB BS, DPhil · Graeme J Hankey MD, FRACP, FRCP · Paul E Norman BSc(Hons), DS, FRACP

Objective: To identify policy strategies that are perceived by researchers active in Aboriginal and Torres Strait Islander health as effective in increasing the amount of high-quality intervention research undertaken in this field.Design and setting: A cross-sectional study using a web-based survey was emailed to researchers based in clinical, public health and other academic institutions.Participants: Researchers who had published more than once in Aboriginal health between 1 January 2005 and 1 August 2009, based on a MEDLINE search.Main outcome measures: Participants selected and weighted 17 strategies that were, in their opinion, important for increasing the amount of high-quality intervention research being conducted in Aboriginal health.Results: We invited 157 researchers to complete the survey, and received 74 completed surveys. The most highly weighted strategies were: for research funding bodies to give funding priority to intervention research proposals that target Aboriginal populations (median weighted score,15%); for peak bodies representing Aboriginal communities to clearly specify intervention research priorities in a national Aboriginal health research agenda (median weighted score, 10%); for research funding bodies to fund research to develop reliable measures of health for Aboriginal people (median weighted score, 9.5%); for health care organisations to participate more in intervention research targeting Aboriginal populations (median, 8.5%); and for research review panels to accept intervention research designs other than the randomised controlled trial (median weighted score, 8%).Conclusions: Researchers who are active in Aboriginal health research perceive that improvements in funding mechanisms, priority setting and research systems are required to increase the amount of high-quality intervention research being conducted in this field. A national intervention research agenda that encourages multidisciplinary research teams and community partnerships may offer a solution.

Jessica M Stewart BA/LLB, MPS · Rob W Sanson-Fisher PhD · Sandra J Eades MB, PhD · Nicole M Mealing BSc(Adv Maths)

Publication deadlines for reporting causes of deaths not yet finalised by coroners and different methods employed by different jurisdictions may have disguised Australia’s true suicide rate Suicide is a topic of public health, public policy and general community interest. Accurate and timely suicide statistics are needed to measure and monitor this cause of death, to guide the development of prevention programs, and to enable evaluation and research.1 The main source of suicide data in Australia is the national mortality database of the Australian Bureau of Statistics (ABS).2 Recently, the ABS data have been used to report reductions in the annual rates and overall numbers of completed suicides since 1997;3,4 another such report, by Large and Nielssen, appears in this issue of the Journal.5 Surely a decline in suicide rates is good news? It is good news if the reported declines have really occurred. However, there are reasons to think that part of the apparent recent decline in suicide, as estimated using ABS data, is the result of changes in the data collection system.1,6-8 The ABS has published cautionary notes concerning suicide statistics in recent years,9,10 and has changed its process for coding deaths registered after 2006, prompted by awareness of the problem of slow finalisation of some cases.1,11 The system underlying cause-of-death statistics is quite complex, and suicide is a particularly challenging cause to record and classify. If a death is suspected to be the result of suicide, an obligation arises to refer it to a coroner. Police, forensic pathologists and staff at the coroner’s office are involved in obtaining and preparing information for the coroner. Sometimes the coroner decides that a formal inquest is warranted, but most cases are dealt with by a simpler administrative process. Details differ between jurisdictions, but the process always results in a conclusion on the cause of death. Coroners are alert to the sensitivity of a finding of “suicide”. Accordingly, they require positive evidence before making a finding of suicide. Findings normally state the means of death (eg, “ligature asphyxiation”), but often remain silent on intent. Coroners’ records are used by ABS officers to guide their selection of a cause of death code. Historically, this information was mainly obtained by ABS officers visiting coroners’ offices and inspecting records. In 2000, an electronic register of coroner cases, the National Coroners Information System (NCIS), commenced operation. ABS officers began to use information in the NCIS, from about 2003, to supplement visits to coroners’ offices; then, from 2006, to replace these visits.11 NCIS records are entered by coroners’ staff. Some information can be entered soon after a death is referred to a coroner, but the record cannot be finished and the finding cannot be entered until the case has been closed by the coroner, sometimes years after the death has occurred. The ABS has operated a system in which all of the deaths registered in a particular year were processed by a deadline, and then reported as final data. For this system to work well, the information that is necessary for coding the causes of all of the deaths registered in that year must be available to the ABS before its deadline. It turned out that the NCIS did not provide complete information on some deaths, including many suicides, in time to meet the ABS deadline.1,9 Often, the mechanism of injury was known by the deadline (eg, gunshot) but the final conclusion on intent was not. Following advice about the use of the International Classification of Diseases codes in this situation, ABS officers assigned to such cases the same codes that are used for unintentional injury deaths.7 Hence, suicide was under-enumerated. The ABS has changed its system for coroner-certified deaths registered after 2006.11 A death registered in 2007 and incomplete in the NCIS at the former ABS deadline (early in 2009) will have been reported in the first release of ABS data on deaths registered in 2007, probably with a code in a range being used as a “holding bay” for incomplete cases (eg, “Hanging, strangulation and suffocation, undetermined intent”), or as unknown cause of death. If the NCIS record for that death closed during 2009, then the ABS reviewed and, if necessary, recoded it for the second release of 2007 deaths data, issued in March 2010.2 Many of the deaths that were initially assigned “holding bay” codes have characteristics suggesting that they will be recoded as suicides when final information is available. As expected, a rise in the number of suicide deaths was observed between the first and second releases of 2007 deaths data, and further rises are likely in subsequent releases. The first estimate of suicides for 2008, based on a further modification of the ABS system, is 2191, which is higher than the first (1881) and second (2054) estimates for 2007. We don’t yet know final ABS suicide numbers for 2007 or 2008. We do know that ABS suicide counts for the several years before that are low. It is likely that this problem reflects the increasing reliance placed on the NCIS by the ABS in the period 2003–2006. Accordingly, a great deal of caution must be employed when interpreting trends in suicide in Australia during the past decade, particularly when making comparisons between jurisdictions (as these have been found to be differentially affected, as a result of differences in coronial processing times1). Unfortunately, it is likely that at least part of the apparent decline since about 2002 shown by ABS statistics and reported by various authors, including Large and Nielssen,5 is an artefact of increased misclassification of suicide deaths. Changes that have been put in place, chiefly by the ABS, are likely to result in materially more reliable suicide statistics in future, providing a better (though still imperfect) basis for efforts to analyse and interpret changes in this important cause of death.

Clare E Bradley PhD · James E Harrison MB BS, MPH · Amr Abou Elnour MB BCh, GradDipPHC

Objective: To assess the impact of the opening of an after-hours general practice clinic on the number of daily low-urgency presentations to the nearby emergency department.Design, participants and setting: Retrospective time series analysis of emergency presentation data, from the New South Wales Health Emergency Department Information System, for all patients presenting to the emergency department of Wagga Wagga Base Hospital between January 1998 and October 2008.Main outcome measures: Daily emergency department presentations, before and after the March 2003 opening of the after-hours clinic, of patients triaged as Australasian Triage Scale (ATS) category 4 or 5 (at any time of day, and during the hours of operation of the clinic), and of patients triaged as ATS category 1, 2 or 3 (at any time of day).Results: After adjusting for long-term trends and weekly and annual cycles, the opening of the after-hours clinic was associated with a daily reduction of 7.04 patients (95% CI, 5.39–8.70) in emergency department presentations with an ATS category of 4 or 5. This represented an 8.2% reduction in total presentations (95% CI, 6.2%–10.2%). Presentations of ATS category 1, 2 or 3 patients rose by 1.36 patients a day (95% CI, 0.36–2.35), representing 1.6% of total presentations (95% CI, 0.4%–2.7%). The impact of the after-hours clinic was best modelled by a gradual permanent change.Conclusion: An after-hours general practice clinic was associated with a reduction in low-urgency presentations to the emergency department in Wagga Wagga.

David J Buckley BVSc(Hons), MVSc · Paul W Curtis MB BS, MHA, FRACMA · Joseph G McGirr MB BS, BSc(Med), FACEM

Suicide and intentional self-harm are issues of major importance in public health and public policy, with rates widely used as progress indicators in these areas. Accurate statistics are vital for appropriately targeted prevention strategies and research, costing of suicide and to combat associated stigma. Underreporting of Australian suicide rates probably grew from 2002 to 2006; Australian Bureau of Statistics (ABS) suicide data were at least 11% or 16% undercounted (depending on case definitions) in 2004. In coronial cases with undetermined intent for 2005 to 2007, intentional self-harm was found in 39%. Systemic reasons for undercounting include: (i) absence of a central authority for producing mortality data; (ii) inconsistent coronial processes for determining intent, as a result of inadequate information inputs, suicide stigma, and high standards of proof; (iii) collection and coding methods that are problematic for data stakeholders; and (iv) lack of systemic resourcing, training and shared expertise. Revision of data after coronial case closure, beginning with ABS deaths registered in 2007, is planned and will reduce undercounting. Other reasons for undercounting, such as missing or ambiguous information (eg, single-vehicle road crashes, drowning), differential ascertainment (eg, between jurisdictions), or lack of recorded information on groups such as Indigenous people and gay, lesbian, bisexual and transgender people require separate responses. A systemic coordinated program should address current inaccuracies, and social stigma about suicide and self-harm must be tackled if widespread underreporting is to stop.

Diego De Leo MD, PhD, FRANZCP · Michael J Dudley MB BS, FRANZCP · Caroline J Aebersold BA(Hons) · John A Mendoza DipTeaching, BEd, GradDipHealthSci · Michael A Barnes BA, LLB, LLM · James E Harrison MB BS, MPH, FAFPHM · David L Ranson BM BS, LLB FRCPA

Objective: To assess the efficacy, with respect to participant understanding of information, of a computer-based approach to communication about complex, technical issues that commonly arise when seeking informed consent for clinical research trials.Design, setting and participants: An open, randomised controlled study of 60 patients with diabetes mellitus, aged 27–70 years, recruited between August 2006 and October 2007 from the Department of Diabetes and Endocrinology at the Alfred Hospital and Baker IDI Heart and Diabetes Institute, Melbourne.Intervention: Participants were asked to read information about a mock study via a computer-based presentation (n = 30) or a conventional paper-based information statement (n = 30). The computer-based presentation contained visual aids, including diagrams, video, hyperlinks and quiz pages.Main outcome measures: Understanding of information as assessed by quantitative and qualitative means.Results: Assessment scores used to measure level of understanding were significantly higher in the group that completed the computer-based task than the group that completed the paper-based task (82% v 73%; P = 0.005). More participants in the group that completed the computer-based task expressed interest in taking part in the mock study (23 v 17 participants; P = 0.01). Most participants from both groups preferred the idea of a computer-based presentation to the paper-based statement (21 in the computer-based task group, 18 in the paper-based task group).Conclusions: A computer-based method of providing information may help overcome existing deficiencies in communication about clinical research, and may reduce costs and improve efficiency in recruiting participants for clinical trials.

Asuntha S Karunaratne BBiomedSc(Hons), PhD · Stanley G Korenman MD · Samantha L Thomas PhD · Paul S Myles MB BS, MD, FCARCSI · Paul A Komesaroff PhD, MB BS, FRACP

To the Editor: The debate raised by Sitas and colleagues about whether smoking status should be recorded on death certificates1 represents data acquisition at the last point. What needs to be considered is not the merits of the proposal, but the systematic failure to record this crucial data in patients’ clinical records. The argument I present here concerns cancer, but may be extrapolated to other smoking-related diseases. The absence of smoking history from the clinical records of patients with cancer up until now is understandable. Unlike the situation with infectious diseases, causative agents have had no relevance to the prognosis or the treatment of malignancy. Even if this pregenomic outlook persisted, the evidence we now have, showing that smoking affects response to therapy (eg, in prostate cancer),2 would warrant documentation of smoking history for every cancer patient. Among developed countries, the risk attributable to smoking in lung cancer is 70%–90%. In single-gene terms, polycyclic aromatic hydrocarbons and tobacco-specific nitrosamines such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone mediate malignant transformation by point mutations in onocogenes and tumour suppressor genes, typified by G-to-T transversions in codons 157, 158, 245, 248 and 273 of TP53; mutations in the KRAS gene and in the gene for epidermal growth-factor receptor (EGFR) are likewise relevant.3 Enough distinction can thus be made between smoking-related and non-smoking-related lung cancer to identify two entities.3 Patients with non-small-cell lung cancer, with exon 19 and 21 mutations in the EGFR gene are typically non-smokers, and their tumours have an 80% response rate to erlotinib.4 Indeed, these tumours respond better to chemotherapy than in patients lacking such mutations.4 As the single-gene era closes, smoking history will be required for all relevant biospecimens to avoid making genomic-wide data on pathways consequent on tobacco-related etiology — representing hundreds of tumours — inaccessible.5 Tobacco smoking causes cancer of the oral cavity, oropharynx, nasopharynx, and hypopharynx, oesophagus (adenocarcinoma and squamous-cell carcinoma), stomach, colorectum, liver, pancreas, nasal cavity and paranasal sinuses, larynx, lung, uterine cervix, ovary (mucinous), urinary bladder, kidney (body and pelvis), ureter and bone marrow (myeloid leukaemia), and possibly causes female breast cancer.6 The prospect of genomic-wide data for these tumours not being accompanied by data on smoking is daunting. The case for smoking data in relation to clinical trials has been made previously.7 Beyond this, the immediate goals for Australia are that smoking history be recorded for tobacco-related malignancies in hospital-based tumour-specific clinical cancer registries and for biospecimens. The need is for the adoption of uniform national vocabulary and coding methods. This will require leadership by an authority such as the National Health and Medical Research Council (NHMRC), the Cancer Council Australia, the Clinical Oncological Society of Australia, or Cancer Australia.

Bernard W Stewart

Registries can provide sound data needed by clinicians and organisations to improve patient safety and quality of care In June 2009, the National Health and Hospitals Reform Commission released its report proposing an agenda to transform the Australian health system.1 A critical element of this agenda is improved monitoring of service delivery and outcomes of care. Clinical-quality registries are an important development in monitoring and benchmarking quality of clinical care. Registries systematically and uniformly collect information from people who undergo a procedure, are diagnosed with a disease or use a health care resource. They are particularly appropriate for monitoring and benchmarking processes and outcomes of care where there is known variation and where poor performance results in high additional cost (eg, renal transplantation) or poor quality of life. Before outcomes are benchmarked, data must be statistically adjusted to isolate quality of care from prognostic factors that are beyond the influence of clinicians. Variables such as age and clinical comorbidities are typically included in risk-adjustment models. Registries are ongoing data-collection exercises, and the validity of their results relies on near-complete inclusion of all eligible patients. To achieve this goal, use of an “opt-out” consent process is recommended. Where registries have used “opt-in” consent, recruitment rates have been as low as one in six of those eligible, making data unreliable for benchmarking, and rendering the registry ineffective.2 Where an opt-out approach has been used in the United States, recruitment rates as high as 97% have been achieved,3 with even higher rates in Australia (< 1% opt-out in the Australian Orthopaedic Association [AOA] National Joint Replacement Registry and Victorian State Trauma Registry). Clinical-quality registries aim to improve quality of care through benchmarking clinical outcomes and stimulating competition in achieving best practice. The registry set up by the Danish Lung Cancer Group exemplifies what can be achieved. Feedback of indicators of high-quality care derived from registry data to those delivering care has been largely responsible for improvement in 30-day, 1-year and 2-year survival rates for people with lung cancer of 1.6%, 8% and 10%, respectively.4 In addition to providing information on safety and efficacy of treatment, data from registries can also be used to determine whether patients have timely access to care,5 and whether care is delivered in line with best practice and evidence-based guidelines.4,6 Process measures are frequently built into clinical-quality registries to detect variations in clinical approach and explore differences in outcomes. For example, stroke registries established in Canada routinely collect data to assess speed and appropriateness of thrombolytic treatment.7 Collection and feedback of data must be underpinned by an effective central governance structure for the registry, with strong clinical leadership, and a regulatory framework providing incentives for quality improvement and proactive approaches for managing poor performance. There must also be strong local clinical leaders who are accountable for ensuring that registry outcomes drive quality improvement. The impact of poor registry governance was highlighted in an inquiry into cardiac surgery at the Bristol Royal Infirmary in the United Kingdom.8 Since the inquiry, improvements have been made to ensure that findings from the Central Cardiac Audit Database are provided to surgeons and are also publicly reported. Clinical-quality registries can improve safety and reduce costs. Findings of the AOA National Joint Replacement Registry show a decline in the rate of hip and knee revision surgery over a 4-year period from 14.8% to 11.1% and from 10.4% to 7.9%, respectively, with an associated annual cost saving of $44.6 million.9 Since its inception in 2001, the Victorian State Trauma Registry has shown a 30% reduction in mortality among trauma victims.10 These improvements may be attributed at least in part to a monitoring system that provides ongoing feedback to contributing sites, detailing their risk-adjusted outcomes relative to those of peer organisations, and to the institution of remedial processes to manage outliers. International momentum is gathering to develop new clinical registries as quality-improvement measures. For example, Sweden has established a network of more than 70 quality registries and has made available resources to assist in establishing new registries.11 In the UK, a national directory of registries has been established to enhance the usefulness of registries in monitoring quality of care.12,13 The US Agency for Healthcare Research and Quality has produced a guide to the design, operation, analysis and evaluation of patient registries.14 In Australia, the document Operating principles and technical standards for Australian clinical quality registries has been developed under the auspices of the Australian Commission on Safety and Quality in Health Care and is now being evaluated.15 Australia has 28 clinical registries, which continuously collect patient-level health-related data, including outcomes, and operate across many health care sites.16 In Australia, new registries are required in a range of areas where improved quality of care is likely to lead to significant improvements in safety and outcomes. A national registry of cardiac procedures and devices has been widely advocated.17 New registries should be established in strong clinical research environments with access to people skilled in clinical epidemiology, biostatistics and clinical data management. Registry custodians must ensure that their registries collect complete data from as many eligible patients as possible; give accurate and timely feedback to clinicians and organisations; and have well-functioning governance structures. They must ensure that lessons are shared among contributors and that data are continuously used to drive improvement in practice. With high-quality data from clinical registries, there is a strong potential to engage clinicians more intensely in quality improvement activities.

John J McNeil FRACP, MSc, PhD · Sue M Evans PhD · Niall P Johnson PhD · Peter A Cameron MB BS, FACEM, MD

Significant problems in health care, such as access block and long waiting lists for elective surgery, have led to calls for keeping hospital occupancy at no more than 85%. It is elementary queueing theory that a finite-capacity system with variable demand cannot sustain both full utilisation and full availability. However, the statement that there is a single level of ideal or safe occupancy suitable for all situations is a simplistic interpretation and application of the underlying science. We argue that specific study and action are necessary to understand and deal with the problems of long waiting lists and access block in any given health care facility.

Christopher A Bain MB BS, MInfoTech, MACS · Peter G Taylor BSc, PhD · Geoff McDonnell FRACP, MEngSci, MIEEE · Andrew Georgiou PhD, FACHI

Objective: To evaluate the difference in time taken for ethics and site governance approval for multicentre clinical trials using two different systems of ethics review.Design: We evaluated the times to final ethics and governance approval for two international, multicentre clinical trials of treatment for metastatic colorectal cancer: the MAX trial, using a non-centralised ethics review system, and the CO.20 trial, using the new New South Wales centralised ethics review system.Main outcome measure: Time from trial submission to overall study approval.Results: The median time taken to obtain ethics approval for the MAX trial at 16 NSW sites was 100 days (range, 36–161 days). The median time to obtain central ethics approval for the CO.20 trial at 14 NSW sites was 77 days, with an additional 60 days (range 20–79 days) required to obtain site-specific research governance approval.Conclusions: Any difference in time to approval between the review systems was outweighed by the overall time taken. However, the time spent by both the coordinating centre and local sites in collation, submission and correspondence was greatly reduced, and the centralised process allowed for standardised documentation at all study sites.

Sian C Hicks BSc(Hons), PhD · Rebecca E James BA/BSc, GradDipEd, MScMed · Nicole Wong RN, BN, BSc(Hons) · Niall C Tebbutt BM BCh, PhD, FRACP · Kate Wilson BA, MPH

Objective: To provide an estimate of the morbidity and mortality resulting from abdominal overweight and obesity in the Australian population.Design and setting: Prospective, national, population-based study (the Australian Diabetes, Obesity and Lifestyle [AusDiab] study).Participants: 6072 men and women aged ≥ 25 years at study entry between May 1999 and December 2000, and aged ≤ 75 years, not pregnant and for whom there were waist circumference data at the follow-up survey between June 2004 and December 2005.Main outcome measures: Incident health outcomes (type 2 diabetes, hypertension, dyslipidaemia, the metabolic syndrome and cardiovascular diseases) at 5 years and mortality at 8 years. Comparison of outcome measures between those classified as abdominally overweight or obese and those with a normal waist circumference at baseline, and across quintiles of waist circumference, and (for mortality only) waist-to-hip ratio.Results: Abdominal obesity was associated with odds ratios of between 2 and 5 for incident type 2 diabetes, dyslipidaemia, hypertension and the metabolic syndrome. The risk of myocardial infarction among obese participants was similarly increased in men (hazard ratio [HR], 2.75; 95% CI, 1.08–7.03), but not women (HR, 1.43; 95% CI, 0.37–5.50). Abdominal obesity-related population attributable fractions for these outcomes ranged from 13% to 47%, and were highest for type 2 diabetes. No significant associations were observed between all-cause mortality and increasing quintiles of abdominal obesity.Conclusions: Our findings confirm that abdominal obesity confers a considerably heightened risk for type 2 diabetes, the metabolic syndrome (as well as its components) and cardiovascular disease, and they provide important information that enables a more precise estimate of the burden of disease attributable to obesity in Australia.

Adrian J Cameron MPH · David W Dunstan PhD · Neville Owen PhD · Paul Z Zimmet MD, PhD · Elizabeth L M Barr MPH · Andrew M Tonkin MD · Dianna J Magliano PhD · Shirley G Murray GradDipPractMan · Timothy A Welborn PhD · Jonathan E Shaw MD

The median age of patients with pandemic influenza H1N1 2009 infection was reported as 20–25 years in initial case series from Europe and the United States. This has been lowered to 13 years in the US after testing of more patients, but this may reflect differential increased testing of school-aged children as part of the pandemic response. The median age of patients with seasonal influenza A(H1N1) infection identified through sentinel surveillance in Western Australia and Victoria in 2007–2008 was 18 and 22 years, respectively. For pandemic influenza H1N1 2009 infection, the median age of the first 244 patients identified in WA was 22 years, and median age of the first 135 patients identified through sentinel surveillance in Victoria was 21 years. Other comparisons of the epidemiological features of pandemic and seasonal influenza are difficult because much less laboratory testing is done for seasonal than for pandemic influenza. While early surveillance data indicated co-circulation of both pandemic and seasonal strains in WA and Victoria, more recent data from both states indicate an increasing predominance of pandemic influenza. If the evolving pandemic allows, we should take advantage of the increased testing being conducted for pandemic influenza to learn more about the real impact of laboratory-confirmed seasonal influenza.

Heath A Kelly BSc, MB BS, MPH · Kristina A Grant BSc · Simon Williams BSc(Hons) · James Fielding BSc(Hons), MAppEpidemiol · David Smith MB BS, FRCPA, FACPM

Australia’s achievement in tobacco control has been remarkable, but relies on indirect estimates of tobacco-attributed mortality, and on using relative risks from Western countries to calculate tobacco’s impact. To accelerate the decline in smoking, more precise measures of tobacco’s relative importance among different population subgroups are required. We propose that more direct and accurate measures of tobacco-attributed mortality are needed, which could be achieved by adding a small set of voluntary questions about the smoking status of the deceased to a revised death notification form. Ideally, this form should also record the smoking status of the next-of-kin or family informant, as this would help establish a living control group. Such information will provide data on tobacco-attributed deaths with incomparable precision, allowing accurate monitoring of the current state of the smoking epidemic, and its evolution over time. This is particularly pertinent for sections of the population in which tobacco control measures have been less successful. A number of practical concerns have been raised, but we do not believe these are insurmountable.

Freddy Sitas MSc(Med), MSc(Epidemiol), DPhil · Dianne L O’Connell BMaths(Hons), PhD · Konrad Jamrozik DPhil, FAFPHM · Alan D Lopez MS, PhD, HonFAFPHM

How you can use the evidence to improve your patients’ outcomes The most recent edition of Heart Foundation guidelines for the management of hypertension is an evidence-based and practical guide for doctors.1 It is self-evident that clinical guidelines need to be used by doctors if they are to improve population health outcomes. Despite publication of multiple editions of the hypertension guidelines, blood pressure (BP) control in Australia is less than ideal.2 The reasons for this are varied, and include health system, doctor and patient factors.3 Here, I outline simple but effective strategies for addressing some of the doctor factors associated with lack of BP control (Box), based on the Heart Foundation guidelines and supplemented by research conducted in Australian general practice. These strategies should help protect patients from stroke, myocardial infarction and other major organ damage, and are all practical in the general practice setting. Although they will not lead to universal control (because other factors are at play), they should help protect against therapeutic inertia and doctors’ doubts about their own self-efficacy — issues that may adversely affect patient health. Get blood pressure measurements from a variety of sources. When doctors measure BP, the measurements they record may differ from the true values, because of measurement error, “white coat effect”, poor technique, single measurements, observer error, and data misinterpretation.4 These problems can be addressed, to some degree, in a variety of ways. One approach is to have someone else, or something else, record BP for adult patients. In clinical practice, BP should be measured repeatedly (and preferably by a nurse) — three times, 5 minutes apart, and the last two measurements averaged. The process can be automated with some oscillometric devices, which further reduces bias.4 Away from the practice, the patient can record their BP on a validated,5 regularly serviced machine that they have been taught to use, or they can have their BP recorded by an ambulatory BP monitor. The latter are superior predictors of hard clinical endpoints compared with clinical measurements.6 Specific advice about technique for patients (as well as clinicians) is covered in the chapter of the Heart Foundation guidelines entitled “Measuring blood pressure”.1 Repeated measurements help reduce measurement error and variability, but they need to be interpreted logically. Suitable home BP monitoring can be achieved by asking the patient to measure BP in the morning and evening, to do so twice on each occasion (2 minutes apart after sitting quietly for 5 minutes), and to record the second measurement in a spreadsheet or diary for use at their next appointment. Interpreting the data can be as simple as highlighting elevated measurements, calculating the percentage of elevated systolic and diastolic measurements, or averaging the measurements. The goal is all or nearly all measurements (or average BP) at or below target levels. When interpreting the data, remember that cut-points are lower for recordings made away from the practice; for example, 135/85 mmHg is the cut-point for BP measured away from the practice in patients with uncomplicated hypertension. Act on absolute risk. In cases where repeated measurements of elevated BP are recorded in at-risk individuals, general practitioners may still not initiate or intensify BP management. Barriers to initiation or adjustment of drug therapy include: clinical uncertainty about underlying true BP and distrust of the technology used to measure BP; distrust of the evidence underpinning the recommendations for management of hypertension; a perceived increased rate of adverse events associated with drug therapy among older patients; perceived patient attitudes towards drug therapy or the need for it; a lack of internal motivation on the part of the practitioner; and health system issues such as lack of time in consultations. The decision to initiate treatment of elevated BP should not be based on BP alone (unless it is very high). An absolute cardiovascular disease risk score should be used, such as the recently released Australian cardiovascular risk charts, that now include risk for Aboriginal and Torres Strait Islander peoples.7,8 This is a more holistic approach than use of a single risk factor — it integrates all risk factors and thus more accurately identifies at-risk individuals. In primary prevention, population risk calculators are required as doctors cannot reliably estimate absolute risk.9 Patients with mildly elevated BP, who are at low absolute risk, do not require drug therapy but still need action on lifestyle factors that affect BP (eg, alcohol intake, diet, overweight/obesity, and physical inactivity). Don’t neglect behavioural factors. GPs recognise that behavioural factors underlie elevated BP and mitigate against effective BP control, but may feel that they have limited influence on their patients’ lifestyle. However, brief advice from a GP is the most cost-effective intervention for smoking cessation.10 Also, walking is a simple, free, all-year activity that GPs can recommend. For overweight patients, caloric restriction can be recommended and, for all patients, recommendations that can be considered include moderation of alcohol intake (do not recommend alcohol to non-drinkers), restriction of salt intake (by reading and interpreting processed food labels), and consumption of fruit and vegetables (two serves of fruit and five serves of vegetables per day). Advice should be supplemented with appropriate referrals (eg, to a dietitian). Accept that most patients will need more than one drug. Most patients will need more than one drug to control their BP.11 This is exacerbated by the need to manage the clustering of risk factors and multiple morbidity, which is common among patients, and especially older patients, with high blood pressure. These factors drive a high evidence-based pill count, which should be distinguished from unnecessary polypharmacy. Thus, the need for two or more drugs to effectively manage hypertension should be communicated to patients from the outset. Follow the guideline recommendations for combinations of drugs. Ways to deal with the necessary polypharmacy in managing high BP in at-risk individuals include: minimising side effects by starting with low doses (especially in older patients and patients with renal impairment), using low-dose combinations, discontinuing ineffective drugs, avoiding agents contraindicated for other conditions that are present, and monitoring for adverse outcomes such as renal impairment; minimising cost by using fixed-dose combinations, generics, agents with a larger number of daily doses dispensed, and drugs listed on the Pharmaceutical Benefits Scheme (avoiding “brand premiums”); increasing adherence by using combination therapies (especially those that allow within-combination dose adjustments); and reducing polypharmacy across morbidities by choosing antihypertensive agents that are indicated for other diseases that are present. Treat to goal. Once treatment of high BP has been moved to an absolute risk basis, the goals are logically reduced to lower levels for those individuals who are at high absolute risk. For example, the guidelines recommend lower BP targets for increasing levels of proteinuria in patients with chronic kidney disease.1 These patients will require greater individual risk factor reduction to reach low risk than patients who are at intermediate risk. This means more drugs, higher doses, higher costs, and greater difficulty in reaching therapeutic targets. In cases where the goal is not being reached, assessing for adherence to drug therapy is important — especially during the initiation of drug therapy. Participants in the Second Australian National Blood Pressure Study who answered yes to the question “Did you ever forget to take your medication?” were significantly more likely to experience a cardiovascular event or death than those who answered no.12 Strategies for dealing with necessary polypharmacy will also help reach the goals of target BP and adherence to drug therapy. The five ways together. Combining these strategies will help to improve BP control via an evidence-based chain of action: obtaining BP measurements systematically, in and away from the general practice setting; stratifying patients according to absolute risk, and acting on risk; considering behavioural measures for all patients; and utilising drugs (usually two or more) for patients who are at high risk, to reach recommended, targeted goals. Simple evidence-based strategies for managing high blood pressure in general practice Get blood pressure measurements from a variety of sources Act on absolute risk Don’t neglect behavioural factors Accept that most patients will need more than one drug Treat to goal

Mark R Nelson MB BS(Hons), FRACGP, PhD

The absolute benefit of a treatment varies between individuals depending on their prognosis before treatment and whether their response to the treatment varies from the overall relative risk reduction measured in clinical trials. Based on these principles, biomarkers that can provide information about an individual’s prognosis or predict his or her treatment response can be used to tailor treatment decisions to individual patients. Many novel molecular biomarkers are currently available. Although there is evidence to show that some of these can improve patient outcomes through improved biomarker-guided treatment strategies, others are yet to be adequately evaluated. Randomised controlled trials (RCTs) can distinguish whether a biomarker provides prognostic or predictive information and assess whether using a biomarker to guide treatment improves patient outcomes. Targeted RCTs can be used to demonstrate the efficacy of treatment in a restricted biomarker-defined population, and non-targeted RCTs can compare biomarker-guided versus conventional test-guided treatment strategies in broader populations.

Chee K Lee MB BS, MMedSci, FRACP · Sarah J Lord MB BS, MS(Epi) · Alan S Coates AM, MD, FRACP · R John Simes MB BS, FRACP, SM

Objective: To determine the incidence of coronary heart disease (CHD) events in an urban Aboriginal population.Design, setting and participants: Cohort study of 906 Aboriginal people without CHD from 998 who had undergone risk-factor assessment in the Perth Aboriginal Atherosclerosis Risk Study (PAARS) in 1998–1999. PAARS cohort data were electronically linked to a range of databases that included Western Australian hospital morbidity data and death registry data. We analysed data from January 1980 to December 2006 to identify previous admissions for CHD from 1980 to baseline (1998–1999) and new events from baseline to 2006.Main outcome measure: First CHD event (hospital admission or death).Results: There were 891 linked records for the 906 participants without previous CHD. The event rate was 12.6/1000 person-years (95% CI, 10.2–15.6/1000 person-years). Annual CHD event rates ranged from 8 to 18/1000 person-years. After adjustment for age (sex was not associated with the risk factors assessed), factors associated with risk of a CHD event in the PAARS cohort were a history of diabetes, overweight or obesity (indicated by body mass index), smoking, and hypertension, but not waist circumference. People with these risk factors were 1.9–2.7 times more likely to experience a CHD event. Compared with previously published information from a remote Aboriginal community in the Northern Territory, the incidence of CHD events among urban-dwelling Aboriginal people was not significantly different (P > 0.05 overall and for subgroups defined by age and sex).Conclusions: City-dwelling Aboriginal Australians have an incidence of CHD events comparable to that of Aboriginal people living in remote northern Australia.

Pamela J Bradshaw PhD · Helman S Alfonso MSc, PhD · Judith C Finn RN, MEdStud, PhD · Julie Owen DipT, MPHC, PhD · Peter L Thompson MD, FRACP, MBA