Proportionally balanced designs: Some further results and general constructions

Proportionally balanced designs were introduced by Gray and Matters in response to a need for the allocation of markers of the Queensland Core Skills Test to have a certain property. Put simply, markers were allocated to pairs of units in proportions that reflected the relative numbers of markers allocated in total to each unit. In this paper, the first author extends the theoretical results relating to such designs and provides further instances, and two general constructions, in the case that the design comprises blocks of precisely two sizes.

Research output of Australian general practice: A comparison with medicine, surgery and public health

Objectives: To compare the productivity of Australian general practice in terms of research publications with the productivity of other medical disciplines. Design: A survey of Australian general practice, medicine, surgery and public health publications carried out by manual searching of specific journals and an electronic search of the US National Library of Medicine's PubMed database. Main outcome measures: The number of original research publications by Australian general practitioners, physicians, surgeons and public health physicians during 1999; the relative publication rate of Australian general practice, medicine, surgery and public health over the period 1990-1999. Results: Of original research articles published in 1999, GPs authored 65% (17/26) in Australian Family Physician and 3% (3/90) in the Medical Journal of Australia; physicians published 4% and 37%, respectively. The electronic search identified 54 research articles relating to Australian general practice published in 1999 in 21 different journals, only two of which were primary care journals. Over the period 1990-1999, there was a publication rate of one general practice [discipline] article per 1000 GPs in practice per year. Corresponding rates for medicine, surgery and public health were 105/1000, 61/1000 and 148/1000, respectively. Conclusions: There is considerable disparity between the level of research output of general practice and that of the disciplines of medicine, surgery and public health. If we are to have effective general practice research, we urgently need to develop research skills, a supportive infrastructure and a culture that nurtures research.

Feasibility of an evidence-based literature search service for general practitioners

Objective: To test the feasibility of an evidence-based clinical literature search service to help answer general practitioners' (GPs') clinical questions. Design: Two search services supplied GPs who submitted questions with the best available empirical evidence to answer these questions. The GPs provided feedback on the value of the service, and concordance of answers from the two search services was assessed. Setting: Two literature search services (Queensland and Victoria), operating for nine months from February 1999. Main outcome measures: Use of the service; time taken to locate answers; availability of evidence; value of the service to GPs; and consistency of answers from the two services. Results: 58 GPs asked 160 questions (29 asked one, 11 asked five or more). The questions concerned treatment (65%), aetiology (17%), prognosis (13%), and diagnosis (5%). Answering a question took a mean of 3 hours 32 minutes of personnel time (95% Cl, 2.67-3.97); nine questions took longer than 10 hours each to answer, the longest taking 23 hours 30 minutes. Evidence of suitable quality to provide a sound answer was available for 126 (79%) questions. Feedback data for 84 (53%) questions, provided by 42 GPs, showed that they appreciated the service, and asking the questions changed clinical care. There were many minor differences between the answers from the two centres, and substantial differences in the evidence found for 4/14 questions. However, conclusions reached were largely similar, with no or only minor differences for all questions. Conclusions: It is feasible to provide a literature search service, but further assessment is needed to establish its cost effectiveness.

Ways of using evidence-based medicine in general practice

General practitioners wanting to practise evidence-based medicine (EBM) are constrained by time factors and the great diversity of clinical problems they deal with. They need experience in knowing what questions to ask, in locating and evaluating the evidence, and in applying it. Conventional searching for the best evidence can be achieved in daily general practice. Sometimes the search can be performed during the consultation, but more often it can be done later and the patient can return for the result. Case-based journal clubs provide a supportive environment for GPs to work together to find the best evidence at regular meetings. An evidence-based literature search service is being piloted to enhance decision-making for individual patients. A central facility provides the search and interprets the evidence in relation to individual cases. A request form and a results format make the service akin to pathology testing or imaging. Using EBM in general practice appears feasible. Major difficulties still exist before it can be practised by all GPs, but it has the potential to change the way doctors update their knowledge.

Injury and alcohol: a hospital emergency department study

A pilot survey was undertaken of injury presentations to a public hospital emergency department to determine patterns of alcohol use in this population. Of the 402 injury presentations in the study period, a total of 236 injury cases were interviewed, of whom 45% (n=107) and 29% (n=69) had consumed alcohol 24 and 6 hours prior to injury. Mean age for all injury presentations was 35.1 years, and 32.6 years for alcohol injury cases. For both injury groups, males were significantly younger than females. Recent alcohol ingestion was three times more common among male than female injury presentations, but with females drinking at significantly lower levels. Of males who had consumed alcohol 6 hours prior to injury, nearly 70% were drinking at NHMRC harmful levels and 61% had drunk more than eight standard drinks. Overall, alcohol-involved injury cases commonly occurred among low-income, single males around 30 years of age who were regular heavy drinkers who were drinking heavily in licensed premises prior to their injury, and who sustained injury through intentional harm. In addition, one in five of the alcohol-involved injury cases were aged 15-18 years, i.e. below the legal age of purchase. The high proportion of hazardous and harmful drinkers among those who had consumed alcohol within the last 6 hours, and the injury sample overall, highlights the need for further research to explore the relationship between the occurrence of injury and the drinking patterns and environments associated with injury. Further research is also required to assess the efficacy of early and brief interventions for alcohol and drug use within the emergency ward setting. This information would enable appropriate public health interventions to be initiated.

Underuse of beta-blockers following myocardial infarction: a tale of two cities

Aims: To measure factors associated with underuse of beta-blocker therapy after myocardial infarction (MI). Methods: The Newcastle and Perth collaborating centres of the World Health Organization (WHO) MONICA project (to MONItor trends and determinants of Cardiovascular disease) systematically evaluated all patients admitted to hospital in their respective regions with possible MI. A total of 1766 patients in Newcastle and 4503 patients in Perth, discharged from hospital after confirmed MI from 1985 to 1993, were studied, Rates of beta-blocker use before and after hospital discharge were evaluated and correlates of beta-blocker use determined. Results: Beta-blocker use was similar in Newcastle and Perth before MI (21% of patients in each centre). During hospital admission, beta-blocker therapy was initiated nearly twice as frequently in Perth compared with Newcastle (66 vs 36%, respectively) and more patients were discharged from hospital on beta-blockers in Perth (68%) than in Newcastle (45%). The main factors associated with underuse of beta-blockers in multivariate analysis were geographical centre (odds ratio (OR) for Newcastle compared with Perth 0.3 95% confidence interval (CI) 0.3-0.3), a history of previous MI (OR 0.6, 95% CI 0.5-0.7), admission to hospital in earlier years (OR 0.4, 95% CI 0.3-0.4 for years 1985-87 compared with years 1991-93), diabetes (OR 0.6, 95% CI 0.5-0.8) and the concomitant use of diuretics (OR 0.5, 95% CI 0.4-0.6) and calcium antagonists (OR 0.6, 95% CI 0.5-0.8). Conclusions: Underuse of beta-blockers after MI was strongly related to hospital prescribing patterns and not to community use of beta-blockers. Underuse occurred in patients with diabetes and in patients with left ventricular dysfunction, patients who stand to benefit most from beta-blocker use following MI.