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Background: Evidence from previous studies is often used relatively informally in the design of clinical trials: for example, a systematic review to indicate whether a gap in the current evidence base justifies a new trial. External evidence can be used more formally in both trial design and analysis, by explicitly incorporating a synthesis of it in a Bayesian framework. However, it is unclear how common this is in practice or the extent to which it is considered controversial. In this qualitative study, we explored attitudes towards, and experiences of, trialists in incorporating synthesised external evidence through the Bayesian design or analysis of a trial.Methods: Semi-structured interviews were conducted with 16 trialists: 13 statisticians and three clinicians. Participants were recruited across several universities and trials units in the United Kingdom using snowball and purposeful sampling. Data were analysed using thematic analysis and techniques of constant comparison.Results: Trialists used existing evidence in many ways in trial design, for example, to justify a gap in the evidence base and inform parameters in sample size calculations. However, no one in our sample reported using such evidence in a Bayesian framework. Participants tended to equate Bayesian analysis with the incorporation of prior information on the intervention effect and were less aware of the potential to incorporate data on other parameters. When introduced to the concepts, many trialists felt they could be making more use of existing data to inform the design and analysis of a trial in particular scenarios. For example, some felt existing data could be used more formally to inform background adverse event rates, rather than relying on clinical opinion as to whether there are potential safety concerns. However, several barriers to implementing these methods in practice were identified, including concerns about the relevance of external data, acceptability of Bayesian methods, lack of confidence in Bayesian methods and software, and practical issues, such as difficulties accessing relevant data.Conclusions: Despite trialists recognising that more formal use of external evidence could be advantageous over current approaches in some areas and useful as sensitivity analyses, there are still barriers to such use in practice. [ABSTRACT FROM AUTHOR]

The article presents a summary of a debate about the affordability of non-functional or decorative public realm lighting in Great Britain. Three categories of people for whom lighting designers are designing are cited, including those who use the scheme. It mentions three projects that summarizes why public realm lighting is not something that should be discarded in times of economic crisis. It notes the need for the private sector to invest in installing and maintaining architectural lighting.

The article focuses on the questionnaire-based survey of health-related lifestyle of adults and children with primary immune thrombocytopenia (ITP) in Great Britain conducted by the ITP Support Association. It says that the questionnaires were mailed to ITP Support Association members and results were separated by age and platelet count at the last follow-up. Results of the survey support recurrent reports of fatigue in patients with primary ITP.

Background: Many studies have examined 'non-specific' vaccine effects on infant mortality: attention has been particularly drawn to diphtheria-tetanus-pertussis (DTP) vaccine, which has been proposed to be associated with an increased mortality risk. Both right and left censoring are common in such studies., Methods: We conducted simulation studies examining right censoring (at measles vaccination) and left censoring (by excluding early follow-up) in a variety of scenarios in which confounding was and was not present. We estimated both unadjusted and adjusted hazard ratios (HRs), averaged across simulations., Results: We identified scenarios in which right-censoring at measles vaccination was informative and so introduced bias in the direction of a detrimental effect of DTP vaccine. In some, but not all, situations, adjusting for confounding by health status removed the bias caused by censoring. However, such adjustment will not always remove bias due to informative censoring: inverse probability weighting was required in one scenario. Bias due to left censoring arose when both health status and DTP vaccination were associated with mortality during the censored early follow-up and was in the direction of attenuating a beneficial effect of DTP on mortality. Such bias was more severe when the effect of DTP changed over time., Conclusions: Estimates of non-specific effects of vaccines may be biased by informative right or left censoring. Authors of studies estimating such effects should consider the potential for such bias and use appropriate statistical approaches to control for it. Such approaches require measurement of prognostic factors that predict censoring., (© The Author(s) 2019; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.)

Bladder cancer is an increasingly important international public health problem, with over 330,000 new cases being diagnosed each year worldwide. In a systematic review and evidence synthesis, the authors investigated the joint effects of the N-acetyltransferase genes NAT1 and NAT2 and cigarette smoking on bladder carcinogenesis. Studies were identified through an exhaustive search of multiple electronic databases and reference lists and through direct contact with study authors and experts. Random-effects meta-analysis was used within a Bayesian framework to investigate individual effects of NAT1 and NAT2 acetylation status on bladder cancer risk, while a novel approach was used to investigate joint effects of these two genes with cigarette smoking. An increased risk of bladder cancer was found in NAT2 slow acetylators (odds ratio = 1.46, 95% credible interval (CI): 1.26, 1.68) but not in NAT1 fast acetylators (odds ratio = 1.01, 95% CI: 0.86, 1.22). The joint effects in the highest risk category (NAT2 slow acetylator, NAT1 fast acetylator, and current or ever cigarette smoking) as compared with the reference category (NAT2 fast acetylator, NAT1 slow acetylator, and never smoking) were associated with an odds ratio of 2.73 (95% CI: 1.70, 4.31). The importance of considering joint effects between genetic and environmental factors in the etiology of common complex diseases is underlined.