We studied 123 patients with malignant peripheral nerve sheath tumours (MPNSTs) between 1979 and 2002. However, 90 occurred sporadically whereas 33 were associated with neurofibromatosis type 1 (NF1). Survival was calculated using Kaplan-Meier survival curves and we used Cox's proportional hazards model to identify independent prognostic factors. A 5-year survival for 110 nonmetastatic patients was 54%; (33% NF1 and 63% sporadic P = .015). Tumour stage and site were significant prognostic indicators after univariate analysis. After multivariate analysis, however, only NF1 (P = .007) and tumour volume more than 200 m (P = .015) remained independent predictors of poor outcome. We recommend that NF1 be taken into account during MPNST staging. As the survival rate in the NF group was dependant on tumour volume, routine screening of these patients with FDG PET and/or MRI may be warranted, thereby staging and controlling them at the earliest possible opportunity.

We have reviewed the data from our regional Bone Tumour Registry on patients with osteosarcoma diagnosed between 1933 and 2004 in order to investigate the relationship between survival and changes in treatment. There were 184 patients with non-metastatic appendicular osteosarcoma diagnosed at the age of 18 or under. Survival was calculated using Kaplan-Meier curves, and multivariate analysis was performed using the Cox regression proportional hazards model. The five-year survival improved from 21% between 1933 and 1959, to 62% between 1990 and 1999. During this time, a multi-disciplinary organisation was gradually developed to manage treatment. The most significant variable affecting outcome was the date of diagnosis, with trends in improved survival mirroring the introduction of increasingly effective chemotherapy. Our experience suggests that the guidelines of the National Institute for Clinical Excellence on the minimum throughput of centres for treatment should be enforced flexibly in those that can demonstrate that their historical and contemporary results are comparable to those published nationally and internationally.

Russ dedicates this book to Michael G. Egleston for his inspiration in handling challenges, great and small, medical and otherwise. I am proud to call you family! Joe dedicates this book to his daughter, Taylor. The two most powerful words in learning are "how" and "why." Never stop wondering how the world works! Emily dedicates this book to all the wonderful teachers and mentors she has had, especially Russ, without whom I would not be where I am today, working in the field of human factors engineering. Bryant dedicates this book to his parents, Larry and Wendy Foster. Thank you for teaching me the value of hard work and that life is meant to be enjoyed.vii PrefaceLike most human factors engineers, I learned about the field completely by accident. As an undergraduate interested in neuroscience, I was pursuing majors in psychology and biology when I took a job as a research assistant in the psychobiology lab. Just prior to that, one of the professors in the department passed away, and his wife donated his entire library to our school. As the assistant, I was tasked with shelving all his books, and one book, Human Engineering Guide to Equipment Design, edited by Harold P. Van Cott and Robert G. Kinkade, caught my eye. As I paged through, I discovered all kinds of facts, figures, and rules about human vision, hearing, memory, attention, and decision making. These weren't just musings or guesses about how people behaved; they were real honest to goodness data compiled from hundreds of scientific studies. It then showed how to apply these scientific facts to design. It combined my interests in psychology and physiology perfectly and, more than that, proved that some lucky people actually did this for a living. I decided immediately to search for graduate programs in human factors.Back then, there were only a few PhD programs in human factors, and they were housed in either psychology (cognitive psychology, engineering psychology, industrial psychology, experimental psychology) or industrial engineering. Interestingly, they taught largely the same courses: Research methods, statistics, sensation and perception, cognition, biomechanics, and of course, human factors, which usually combined the other topics.All four of us have stories somewhat similar to this. We were studying something related, learned about human factors engineering (HFE) by chance, and recognized we had a real affinity for it. In recent years, device manufacturers, hospitals, and regulatory entities have recognized the perils of medical device use error and the need for human factors engineering. Because devices failed to accommodate wellknown human capabilities and limitations, patients, providers, and caregivers were injured or died. This has led more people to discover the field and recognize their affinity for it, as well.Rather than human factors engineering degrees, however, practitioners often have backgrounds in mechanical engineering, quality engineering, medicine, technical communications, industrial design, user experience design, or servic...