That the effects of smoking should be measured in pack-years: misconceptions 4.

Lung cancer incidence in smokers is roughly proportional to dose rate (cigarettes per day) but increases much more rapidly with duration of smoking. The assumption that the incidence rate is proportional to total lifetime dose (the product of dose rate and duration) has been known to be wrong for many years, but total dose in pack-years is still often included, either alone or together, with more fundamental parameters such as dose rate, in regression analysis of epidemiological data. This is mathematically unnecessary and scientifically unhelpful

Too Immature to Vote?

This article argues in favour of lowering the voting age to 16. First, it outlines a respect-based account of democracy where the right to vote is grounded in a respect for citizens’ autonomous capacities. It then outlines a normative account of autonomy, modelled on Rawls’s two moral powers, saying what criteria must be met for an individual to possess a (pro tanto) moral right to vote. Second, it engages with empirical psychology to show that by the age of 16 (if not earlier) individuals h

The expected burden of mesothelioma mortality in Great Britain from 2002 to 2050

The British mesothelioma register contains all deaths from 1968 to 2001 where mesothelioma was mentioned on the death certificate. These data were used to predict the future burden of mesothelioma mortality in Great Britain. Poisson regression analysis was used to model male mesothelioma deaths from 1968 to 2001 as a function of the rise and fall of asbestos exposure during the 20th century, and hence to predict numbers of male deaths in the years 2002–2050. The annual number of mesothelioma deaths in Great Britain has risen increasingly rapidly from 153 deaths in 1968 to 1848 in 2001 and, using our preferred model, is predicted to peak at around 1950 to 2450 deaths per year between 2011 and 2015. Following this peak, the number of deaths is expected to decline rapidly. The eventual death rate will depend on the background level and any residual asbestos exposure. Between 1968 and 2050, there will have been approximately 90 000 deaths from mesothelioma in Great Britain, 65 000 of which will occur after 2001

Pleural mesothelioma and lung cancer risks in relation to occupational history and asbestos lung burden.

BACKGROUND: We have conducted a population-based study of pleural mesothelioma patients with occupational histories and measured asbestos lung burdens in occupationally exposed workers and in the general population. The relationship between lung burden and risk, particularly at environmental exposure levels, will enable future mesothelioma rates in people born after 1965 who never installed asbestos to be predicted from their asbestos lung burdens. METHODS: Following personal interview asbestos fibres longer than 5 µm were counted by transmission electron microscopy in lung samples obtained from 133 patients with mesothelioma and 262 patients with lung cancer. ORs for mesothelioma were converted to lifetime risks. RESULTS: Lifetime mesothelioma risk is approximately 0.02% per 1000 amphibole fibres per gram of dry lung tissue over a more than 100-fold range, from 1 to 4 in the most heavily exposed building workers to less than 1 in 500 in most of the population. The asbestos fibres counted were amosite (75%), crocidolite (18%), other amphiboles (5%) and chrysotile (2%). CONCLUSIONS: The approximate linearity of the dose-response together with lung burden measurements in younger people will provide reasonably reliable predictions of future mesothelioma rates in those born since 1965 whose risks cannot yet be seen in national rates. Burdens in those born more recently will indicate the continuing occupational and environmental hazards under current asbestos control regulations. Our results confirm the major contribution of amosite to UK mesothelioma incidence and the substantial contribution of non-occupational exposure, particularly in women

Role of advanced technology in the detection of sight-threatening eye disease in a UK community setting.

Background/aims: To determine the performance of combinations of structural and functional screening tests in detecting sight-threatening eye disease in a cohort of elderly subjects recruited from primary care. Methods: 505 subjects aged ≥60 years underwent frequency doubling technology (FDT) perimetry, iVue optical coherence tomography (iWellness and peripapillary retinal nerve fibre layer (RNFL) scans) and intraocular pressure with the Ocular Response Analyzer, all performed by an ophthalmic technician. The reference standard was a full ophthalmic examination by an experienced clinician who was masked to the index test results. Subjects were classified as presence or absence of sight-threatening eye disease (clinically significant cataract, primary open-angle glaucoma, intermediate or advanced age-related macular degeneration and significant diabetic retinopathy). Univariate and multivariate logistic regression analyses were used to determine the association between abnormal screening test results and the presence of sight-threatening eye disease. Results: 171 subjects (33.8%) had one or more sight-threatening eye diseases. The multivariate analysis found significant associations with any of the target conditions for visual acuity of <6/12, an abnormal FDT and peripapillary RNFL thickness outside the 99% normal limit. The sensitivity of this optimised screening panel was 61.3% (95% CI 53.5 to 68.7), with a specificity of 78.8% (95% CI 74.0 to 83.1), a positive predictive value of 59.5% (95% CI 53.7 to 65.2) and an overall diagnostic accuracy of 72.9% (95% CI 68.8 to 76.8). Conclusions: A subset of screening tests may provide an accurate and efficient means of population screening for significant eye disease in the elderly. This study provides useful preliminary data to inform the development of further larger, multicentre screening studies to validate this screening panel