Impact numbers: measures of risk factor impact on the whole population from case-control and cohort studies

Objective: To describe new measures of risk from case-control and cohort studies, which are simple to understand and relate to numbers of the population at risk. Design: Theoretical development of new measures of risk. Setting: Review of literature and previously described measures. Main results: The new measures are: (1) the population impact number (PIN), the number of those in the whole population among whom one case is attributable to the exposure or risk factor (this is equivalent to the reciprocal of the population attributable risk),- (2) the case impact number (CIN) the number of people with the disease or outcome for whom one case will be attributable to the exposure or risk factor (this is equivalent to the reciprocal of the population attributable fraction); (3) the exposure impact number (EIN) the number of people with the exposure among whom one excess case is attributable to the exposure (this is equivalent to the reciprocal of the attributable risk); (4) the exposed cases impact number (ECIN) the number of exposed cases among whom one case is attributable to the exposure (this is equivalent to the reciprocal of the aetiological fraction). The impact number reflects the number of people in each population (the whole population, the cases, all those exposed, and the exposed cases) among whom one case is attributable to the particular risk factor. Conclusions: These new measures should help communicate the impact on a population, of estimates of risk derived from cohort or case-control studies.

Alcohol, tobacco and breast cancer - collaborative reanalysis of individual data from 53 epidemiological studies, including 58 515 women with breast cancer and 95 067 women without the disease

Alcohol and tobacco consumption are closely correlated and published results on their association with breast cancer have not always allowed adequately for confounding between these exposures. Over 80% of the relevant information worldwide on alcohol and tobacco consumption and breast cancer were collated, checked and analysed centrally. Analyses included 58515 women with invasive breast cancer and 95067 controls from 53 studies. Relative risks of breast cancer were estimated, after stratifying by study, age, parity and, where appropriate, women's age when their first child was born and consumption of alcohol and tobacco. The average consumption of alcohol reported by controls from developed countries was 6.0 g per day, i.e. about half a unit/drink of alcohol per day, and was greater in ever-smokers than never-smokers, (8.4 g per day and 5.0 g per day, respectively). Compared with women who reported drinking no alcohol, the relative risk of breast cancer was 1.32 (1.19 - 1.45, P < 0.00001) for an intake of 35 - 44 g per day alcohol, and 1.46 (1.33 - 1.61, P < 0.00001) for greater than or equal to 45 g per day alcohol. The relative risk of breast cancer increased by 7.1% (95% CI 5.5-8.7%; P

An evaluation of tobacco brief intervention training in three Indigenous health care settings in north Queensland

Objective: To evaluate the pilot phase of a tobacco brief intervention program in three Indigenous health care settings in rural and remote north Queensland. Methods: A combination of in-depth interviews with health staff and managers and focus groups with health staff and consumers. Results: The tobacco brief intervention initiative resulted in changes in clinical practice among health care workers in all three sites. Although health workers had reported routinely raising the issue of smoking in a variety of settings prior to the intervention, the training provided them with an additional opportunity to become more aware of new approaches to smoking cessation. Indigenous health workers in particular reported that their own attempts to give up smoking following the training had given them confidence and empathy in offering smoking cessation advice. However, the study found no evidence that anybody had actually given up smoking at six months following the intervention. Integration of brief intervention into routine clinical practice was constrained by organisational, interpersonal and other factors in the broader socio-environmental context. Conclusions/implications: While modest health gains may be possible through brief intervention, the potential effectiveness in Indigenous settings will be limited in the absence of broader strategies aimed at tackling community-identified health priorities such as alcohol misuse, violence, employment and education. Tobacco and other forms of lifestyle brief. intervention need to be part of multi-level health strategies. Training in tobacco brief intervention should address both the Indigenous context and the needs of Indigenous health care workers.

Public Intellectuals, Book Culture and Civil Society

Introduction: the rise and rise of the public intellectual My starting point is the remarkable rise to prominence of public intellectuals – and talk about public intellectuals – over the last decade in Australia. Since 1997, especially, this has occurred around Indigenous questions with the result that issues such as the stolen generations, genocide, the apology and reconciliation have also gained new prominence. This is undeniably a good thing. New ways of thinking about history and the nation and new kinds of public ethical discourse have been put into circulation. History as battleground is preferable to the great Australian silence. And yet – my starting point is also the ambivalent effects and meanings of these recent developments, not least the way that the debates have centred so much around the figure of the 'public intellectual', the way that certain kinds of intellectuals and intellectual discourse have come to dominate the mainstream representation of the issues.