There are areas of medical research that are more legitimate than others. Finding genes is OK, as is finding drugs. But other bits of the health enterprise seem immune to rational scrutiny. One area that has bugged me for years is the way hospitals, charities, professional bodies and others plaster images of skin cancer around, on the assumption that this will ‘make things better’. It might, or it might not. So here is a recent paper of ours on this topic. Take away message: if there is a fixed resource envelope, many if not most strategies may make matters worse. The abstract is below. The images will of course remain up — I am not certain the rationale is the obvious one.
Abstract: Using an experimental task in which lay persons were asked to distinguish between 30 images of melanomas and common mimics of melanoma, we compared various training strategies including the ABC(D) method, use of images of both melanomas and mimics of melanoma, and alternative methods of choosing training image exemplars. Based on a sample size of 976 persons, and an online experimental task, we show that all the positive training approaches increased diagnostic sensitivity when compared with no training, but only the simultaneous use of melanoma and benign exemplars, as chosen by experts, increased specificity and diagnostic accuracy. The ABCD method and use of melanoma exemplar images chosen by laypersons decreased specificity in comparison with the control. The method of choosing exemplar images is important. The levels of change in performance are however very modest, with an increase in accuracy between control and best-performing strategy of only 9%.
Authors: Ella Cornell, Karen Robertson, Robert D. McIntosh, Jonathan L. Rees
Full open access paper here.
“Pace Arrowsmith, most of us find the flash of personal insight that leads to scientific advance more attractive than the gradual accrual of knowledge from giant research teams. Most of us prefer the idiosyncrasies of the quixotic Sherlock Holmes to the giant team-based logistic-rich police forces that are said to be more efficient in dealing with modern crime. Most of us prefer the idea of the personal physician to the medical production line. But, most of us would, I suspect, choose a production line Volkswagen or Toyota than a car made by a single craftsman, however skilful the latter.” Here.
“What of attempts to improve skin cancer diagnostic skills in primary care, or to develop GP specialists as seen in Australia or the UK? There are various points to make here, and perhaps a lot of wishful thinking about how the problem could be solved if only ‘GPs’ knew more about this or that subdomain of medical knowledge. In truth, such blandishments, must be frustrating to many GPs: there are only so many hours in the day. There are studies showing that it is possible to improve diagnostic skills over the short term following organised tuition (cited in Rees (16)). To find anything else would of course be surprising: if we expose intelligent people to formal tuition or learning, we expect short-term performance to improve. But, the critical point is whether this improvement is maintained, and what aspects of performance suffer because they have been replaced by training in another domain (16). There is no free lunch. If we run a course on skin cancer, then the rheumatologists, cardiologists etc. will all want to run courses. And much of what we know about such one off tuition is that in the absence of consolidation and feedback, the benefits are short lived only. How many of us remember all the history and geography we learned at school?” Here.