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BackgroundBalangero, 40 km northwest of Torino in the Piedmonte Region, was home to the largest and most active chrysotile mine in Europe operating from 1916 - 1990 and employed over 300 men at any one time. The chrysotile was thought to be pure. Despite this some claim it has been responsible for causing numerous mesotheliomas. This report refutes this claim on the grounds that it is not pure but potentially contaminated by tremolite asbestos. In addition there are numerous alternate sources of naturally occurring and commercially available amphibole asbestos in the region.MethodsGeological studies illustrate the presence of naturally occurring tremolite and various analyses have shown naturally occurring and commercially used amphibole its presence in animal and human tissue. The diagnostic criteria used to study pleural disease in the Balangero cohort were examined on a case by case basis. ResultsSeveral authors have searched available registries for post-mortem information and listed possible mesothelioma cases. Cross matching these searches has been attempted and the strength of their diagnoses examined. Conclusion.There is good evidence that crocidolite, amosite and tremolite are responsible for the alleged mesothelioma cases at Balangero. Myriad sources of naturally occurring and commercial amphibole asbestos exist in the region to account for the alleged cases. Regrettably, necessary information is incomplete and insufficient for the cohort which calls the diagnostic accuracy of the cases into question. The problem is further compounded by confusion surrounding job titles and raises the question if any of cases actually ever occurred in ‘miners’ per se.

Background Performing well-powered randomised controlled trials (RCTs) of new treatments for rare diseases is often infeasible. However, with the increasing availability of historical data, incorporating existing information into trials with small sample sizes is appealing in order to increase the power. Bayesian approaches enable one to incorporate historical data into a trial’s analysis through a prior distribution. Methods Motivated by a RCT intended to evaluate the impact on event-free survival of mifamurtide in patients with osteosarcoma, we performed a simulation study to evaluate the impact on trial operating characteristics of incorporating historical individual control data and aggregate treatment effect estimates. We used power priors derived from historical individual control data for baseline parameters of Weibull and piecewise exponential models, while we used a mixture prior to summarise aggregate information obtained on the relative treatment effect. The impact of prior-data conflicts, both with respect to the parameters and survival models, was evaluated for a set of pre-specified weights assigned to the historical information in the prior distributions. Results The operating characteristics varied according to the weights assigned to each source of historical information, the variance of the informative and vague component of the mixture prior and the level of commensurability between the historical and new data. When historical and new controls follow different survival distributions, we did not observe any advantage of choosing a piecewise exponential model compared to a Weibull model for the new trial analysis. However, we think that it remains appealing given the uncertainty that will often surround the shape of the survival distribution of the new data. Conclusion In the setting of Sarcome-13 trial, and other similar studies in rare diseases, the gains in power and accuracy made possible by incorporating different types of historical information commensurate with the new trial data have to be balanced against the risk of biased estimates and a possible loss in power if data are not commensurate. The weights allocated to the historical data have to be carefully chosen based on this trade-off. Further simulation studies investigating methods for incorporating historical data are required to generalise the findings. Electronic supplementary material The online version of this article (10.1186/s12874-019-0714-z) contains supplementary material, which is available to authorized users.

Objective: We investigated whether patients with chronic obstructive pulmonary disease (COPD) who were enrolled in disease-management programmes (DMPs) felt that they received a better quality of care than non-enrolled COPD patients. Methods: Our cross-sectional study was performed among patients (n = 665) enrolled in four DMPs in The Netherlands. We also evaluated COPD patients (n = 227) not enrolled in such programmes. Patients' assessment of chronic-illness care (PACIC) was measured with a 20-item questionnaire. The instrument had five pre-defined domains: patient activation (three items), delivery-system/practice design (three items), goal setting/tailoring (five items), problem solving/contextual (four items), and follow-up/coordination (five items). Results: The mean overall PACIC score (scale: 1-5) of enrolled DMP patients was 2.94, and that of non-enrolled DMP patients was 2.73 (p ≤ 0.01). Differences in the same direction were found in the subscales of patient activation (p ≤ 0.01), delivery-system/practice design (p ≤ 0.001), and problem solving/contextual (p ≤ 0.001). Conclusions: Our results suggest that even in the early stages of implementation, DMPs for COPD may significantly improve care.