A tribute to Professor Steve R. Cummings

With Steve, I have a lot of memories that go back 30 years. In the early 1990s, when I joined Professor John Eisman’s group working in the Dubbo Osteoporosis Epidemiology Study, John showed me a list of work that I should read, and Steve’s papers were on the top of the list. I was mesmerized with his ideas, his methodological approach, and his writing. Subsequently, Steve’s work has inspired many of my work on osteoporosis.

My work in the residual lifetime risk of fracture [1] actually followed his initial paper on lifetime risks of hip, Colles’ and vertebral fracture in 1989 [2]. That 1989 paper has introduced me to the idea of ‘residual lifetime risk’, and I was so fascinated by the math behind the idea. In 1993, Steve and I independently found that people with lower bone mineral density had higher risk of fracture. His work was published in Lancet [3], and mine in BMJ [4].

My work on risk factors for hip fracture [5] was also inspired by his influential paper on the same topic in 1995 [6]. We reviewed that paper in a Journal Club, and we tried to find a weakness of the paper so that we could do better, but we could hardly find any major weakness. When my students and I discussed about a way to show the ‘synergistic effect’ of risk factors on hip fracture risk, Dr. Nguyen D Nguyen (my student at the time) presented the group Steve’s 3D figure in which he and his coauthors showed that for any given BMD level, the risk of fracture linearly increased with the number of non-BMD risk factors. We eventually did use this type of presentation in our paper.

I meet Steve every year at ASBMR conferences, and we discuss new ideas. In an ASBMR, I discussed with Steve about a predictive model that would allow doctors and patients alike to estimate their ‘personal risk’ of fracture. Steve thought that was a great idea and said “Well, you have the data, what are you waiting for?” So, we did develop the model that is now known as “Garvan Fracture Risk Calculator” [7–8]. In the subsequent conference, we met again, Steve patted on my shoulder and said to: “That is an elegant model”. I very much appreciated his comment.

At conferences, I always look for his questions, but with … nervousness. The reason is that he always comes up with brilliant questions, but in the mean time, I know that his questions can be difficult. However, Steve has always (I mean always) been kind to younger colleagues. At a conference in Hong Kong, he challenged me about a statistical…