The Cytel blog keeps you up to speed with the latest developments in biostatistics and clinical biometrics.

‘A blend of courage and foolhardiness’: Marvin Zelen's 8 Predictions for the Future of Biostatistical Sciences

May 14, 2015

Ten years ago, in May 2005, world-renowned biostatistician Marvin Zelen was asked to deliver a keynote address before the Eastern Mediterranean Region of the Biometric Society. His address, entitled ‘Biostatisticians, Biostatistical Science and the Future,’ [1] offered a reflection on the direction which the field at large would have to take, given the anticipated leaps in software and the rise of big data.

This included eight predictions on how short and longer term advances in technology would shape the field.

As we prepare to celebrate the annual Marvin Zelen Leadership Award in Statistical Science, this year awarded to Professor Nan Laird (Harvard University) [2] [3] we can take a moment to re-examine the predictions and insights of Cytel's beloved friend and Board Member. 


Where will the field of biostatistical sciences be ten years from now? Thirty years from now? How about one hundred years from now? It is perhaps a guessing game full of imprecise probabilities and chances for Bayesian updating.

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Remembering Marvin Zelen

November 17, 2014

Outstanding Thought Leader, Scientist and Humanitarian, Passes away at Age 87

It is with immense sadness that we announce that Marvin Zelen, one of the foremost statisticians of our time, widely regarded as the Father of Clinical Trials, and mentor to hundreds of younger colleagues passed away on November 15, 2014. Professor Zelen was the former Chairman of the Department of Biostatistics at Harvard School of Public Health and built it up into one of the best departments in the world by his leadership, personality and ability to attract first-rate scientists. Almost everyone who had the good fortune to work with Marvin went on to achieve fame and success. But beyond his intellectual prowess, Marvin was a wonderful human being. He was gracious to younger colleagues and went out of his way to help them in every way possible.

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Data Management and Biostatistics III: Statistical Innovation in Clinical Data Management

July 24, 2014

This is the third post in a three part series in which we consider (i) improvements to trial quality that result from bundling data management with biostatistics, (ii) reductions in cost and study length that result from bundling data management with biostatistics, and (iii) the contributions of statistical innovation to clinical data management, such as those by Cytel Board member Professor Marvin Zelen (Research Professor and former Chair of Biostatistics at the Harvard School of Public Health.)

For previous posts click here: 

“They’d report somebody dead, and two months later they’d report that the person was taking therapy.” [1]

This was clinical data in the early 1960s, according to Marvin Zelen, Research Professor in Biostatistics at the Harvard School of Public Health. More precisely, this was emblematic of the type of frustration that led Zelen and others at the Eastern Cooperative Oncology Group to develop the role, function and methodology of ‘data management’ in efforts to improve data quality for confirmatory clinical trials. 

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2014 Zelen Award Honors Statistician and Educator

May 29, 2014

Cytel has taken the initiative to train the next generation of clinical programmers through its innovative Clinnical Programming Laboratory [see Cytel's CliPLab].

What about training the next generation of statisticians? The Harvard School of Public Health has just awarded the 2014 Marvin Zelen Leadership Award in Statistical Sciences to a distinguished statistician and educator. 

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StatXact 25th Anniversary: A Horizon for the Stars

April 21, 2014

The core methodological problem that would eventually spur the development of Cytel’s StatXact software was first posed by Harvard’s Marvin Zelen at a computational seminar in the late 1970s. Zelen, a distinguished professor of statistical sciences and head of the Department of Biostatistics at Harvard University, was also serving as the Director of the Dana Farber Cancer Institute.

The analysis of serious adverse events from cytotoxic agents in oncology trials were heavily dependent on an imprecise Cochran rule to measure the signifincance of small sample categorical data. The crude calculation meant that estimations of p-values were wide off the mark. Zelen challenged his students to find ways to expand Fisher’s exact test to r x c contingency tables, and by doing so to seal the promise of more effective development and delivery of urgent cancer treatments.

Cyrus Mehta and Nitin Patel took up Zelen’s challenge, publishing a series of papers on exact significance testing throughout the 1980s. Despite offering novel statistical solutions to persisting problems, the implementation of such solutions clearly required assistance from software. Unfortunately, few venture capitalists were willing to invest in a package of arcane statistical tests that were largely still in development.

Cytel was created with a grant from the National Cancer Institute, with a view to developing software that would make newer exact tests widely available for clinical studies. Its first software package, StatXact, is now used for exact testing in oncology, as well as environmental studies, public health, demography, law, and several areas of medicine and clinical development. The widespread use of exact tests has led to an array of intriguing research questions involving the power of various exact tests. Below we present a favorite finding, on the power of conditional versus unconditional exact tests:

Mehta, Cyrus R., and Pralay Senchaudhuri. "Conditional versus unconditional exact tests for comparing two binomials." Cytel Software corporation 675 (2003).


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