Immortal time bias in survival analysis
Whilst reviewing an article submitted to a transplant journal recently, my attention was brought to an issue that is often overlooked in survival analysis, called ‘immortal time bias’. The issue arises when the groups to be compared in the analysis are defined by a time-dependent event that can occur any time during follow-up. As standard […]
Read moreThe explosion of systematic reviews – have we gone too far?
A fascinating recent paper from Professor John Ioannidis from Stanford University, published in the Milbank Quarterly, has examined the explosion in the publication of systematic reviews and meta-analyses over recent years. Publications between 1991 and 2014 increased by 2,728% for systematic reviews, and 2,635% for meta-analyses – far in excess of the rate of publication […]
Read moreOutcomes after bilateral hand allotransplantation: a risk/benefit ration analysis
This is an interesting long term report of five patients who had bilateral hand allotransplants performed in the Lyon centre some years ago with a follow up ranging from three to 13 years. There were four men and one woman and all were young and the level of amputation was distal in three cases and […]
Read moreHIV Positive to HIV positive kidney transplantation- results at 3-5 years
Although the outcome of kidney transplantation in HIV positive patients who receive organs from HIV negative donors has been reported as being similar to the outcome in HIV negative recipients, this report from South Africa is the first long term follow up of HIV positive patients who receive kidneys from HIV positive deceased donors. Over […]
Read moreDeviation from intention-to-treat analysis alters treatment effect
A recent article in the BMJ by Abraha et al, using large amounts of data from RCTs, has shown that deviation from intention-to-treat analysis (ITT) can lead to apparently larger treatment effects. When compared to standard intention-to-treat analysis there was a significant difference in the apparent treatment effect. When a deviation from ITT was compared […]
Read moreDonor specific HLA alloantibodies (DSA) in liver transplantation
A conference was held with an invited faculty (predominantly from the USA) and sponsored by industry to discuss the impact of DSA in liver transplantation and this article reports their opinions. It was agreed that the presence of DSA are recognised now to have a deleterious effect on outcome, particularly if HLA Class II antibodies, […]
Read moreOrigins of Evidence Based Medicine
There was an interesting editorial by Richard Smith and Drummond Rennie in the BMJ recently. The editorial is based on two interviews of pioneers in this field by Richard Smith, the former editor of the BMJ. In the first oral history he interviews Iain Chalmers, Muir Gray and David Sackett. They said that authors from a […]
Read moreCompliance with the Consort Statement in Surgery
Recently, the Centre for Evidence in Transplantation published an analysis of compliance with the CONSORT statement in reports of randomised controlled trials (RCTs) in transplantation, and found that the compliance left much to desire. A recent article in the Annals of Surgery analysed Consort compliance in 150 recently published RCTs in surgery, most of these being in […]
Read moreTrial methodology – is it small-print?
As any regular reader of peer-reviewed journals will know, the most important section of any paper is the description of methods. Without the information in the methods section it is almost impossible to interpret the results of a paper and determine whether the author’s conclusions are justified. Indeed, it is often justifiable to bin a […]
Read moreSurgical Ethics
This editorial by Professor Daniel Sokol on Surgical Ethics is well worth noting. Professor Sokol is a Barrister and also a Senior Lecturer in Medical Ethics at Imperial College. He has written a very perceptive editorial on this subject which is entirely relevant to transplant surgeons. But he also makes the point that the pamphlet […]
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