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Environmental Factor

Environmental Factor

Your Online Source for NIEHS News

December 2017

NIEHS researchers use video to promote science

NIEHS scientists Allen Wilcox and Paul Wade each took time away from their research to contribute to science videos.

Most scientists prefer spending time doing research rather than standing in front of a camera, but NIEHS researchers Allen Wilcox, M.D., Ph.D., and Paul Wade, Ph.D., took time away from their studies to contribute to two science videos.

Wilcox’s video was part of an online course on causal diagrams, a type of visual logic used for understanding causality. Wade’s video supported a new way for scientists at the National Institutes of Health (NIH) to find the research services they need.

Association is not causation

Allen Wilcox Wilcox leads the NIEHS Reproductive Epidemiology Group. (Photo courtesy of Steve McCaw)

Wilcox said that epidemiologists started using causal diagrams about 20 years ago, and now the tool has become a mainstay in the field. It turns out that birth weight, a topic Wilcox worked on for decades, is a good illustration of the usefulness of the diagrams.

Birth weight is an excellent illustration of causality because birth weight is easy to measure and strongly related to survival of the baby, Wilcox said. But if researchers assume that low birth weight causes mortality, then strange paradoxes arise in the results.

The best explanation for the paradoxes comes from studying causal diagrams, according to Wilcox. If scientists assume that low birth weight is simply a marker of some prenatal problem that has made the baby small and also causes its high risk of mortality, then the paradoxes go away.

He said not every epidemiologist is a fan of causal diagrams, because they can be complex and confusing. Nevertheless, he finds them invaluable for clarifying certain kinds of misinterpretations that epidemiological studies are vulnerable to.

"I was an epidemiologist for a long time before I knew anything about causal diagrams, and now I can’t imagine working without them," Wilcox said. "I hope the video will help people understand the practical applications of this theoretical tool."

relationship of residential air pollution exposure to inflammatory markers Causal diagram for the investigation of the relationship of residential air pollution exposure to inflammatory markers, from Chronic Residential Exposure to Particulate Matter Air Pollution and Systemic Inflammatory Markers. PM — particulate matter. SES — socioeconomic status. (Photo courtesy of Environmental Health Perspectives)

Wade makes CREx pitch

Wade helped promote the NIH Collaborative Research Exchange (CREx), a new online platform that allows NIH scientists to quickly find research services and core facilities. Wade, who was NIEHS acting deputy scientific director when his video was shot, said CREx enables NIH researchers to gather quotes, exchange files and project reports, and manage purchases from a single dashboard. Scientists may also compare services from 170 NIH cores and more than 18,000 commercial vendors.

Paul Wade Wade is deputy chief of the NIEHS Epigenetics and Stem Cell Laboratory and heads the Eukaryotic Transcriptional Regulation Group. (Photo courtesy of Steve McCaw)

"CREx is incredibly easy to use and lets me rate the services provided," Wade said.

David Goldstein, Ph.D., associate director of the National Cancer Institute Office of Science and Technology Resources (NCI-OSTR) and Mariam Malik, Ph.D., assistant director for partnerships at NCI-OSTR, started developing CREx five years ago. They wanted a way to ensure that researchers at NIH could find exactly what they needed to do their work.

NCI contractor and CREx Scientific Program Manager Lakshmi Darbha, Ph.D., produced the video. She and her colleagues are starting to see how CREx is changing the research landscape at NIH, Darbha said.

"The CREx platform is fast evolving as per NIH researchers’ needs and is an essential part of any research project planning," Darbha said.

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