In a single week last September, Keith E. Muller, Ph.D., and his co-investigator Deborah H. Glueck, Ph.D., received two grants from the National Institutes of Health. Muller is a professor in the Department of Health Outcomes and Policy in the University of Florida College of Medicine, and Glueck is an associate professor of biostatistics and informatics in the University of Colorado Denver School of Public Health. The grants provide funding to create educational materials for the design of multilevel and longitudinal research studies. Multilevel designs involve observations related to each other, creating clusters of data points, while longitudinal designs collect repeated data points over time. The designs give greater precision in analyzing how individuals and groups change over time. Both types of studies are crucial for biomedical scientists and researchers in a wide variety of related fields.
The first grant, which is from the National Library of Medicine and totals $50,000 per year for three years, will allow Muller and Glueck to write a textbook on how to design multilevel and longitudinal studies effectively. The textbook will be entitled “Power and Sample Size for Multilevel and Longitudinal Designs in Health Research.”
The second grant, which is from the National Institute of General Medical Sciences and totals roughly $200,000 per year for four years, will facilitate the creation of a short course on multilevel and longitudinal health studies. The course, entitled “Power and Sample Size for Multilevel and Longitudinal Designs in Health Research,” is aimed at practicing scientists, especially those from groups historically underrepresented in biomedical research. The team that will create the course also includes Mildred Maldonado-Molina, Ph.D., associate professor and director of training and education in the Department of Health Outcomes and Policy; Henry Frierson, Ph.D., associate vice president and dean of the UF Graduate School; and Albert Ritzhaupt, Ph.D., associate professor of educational technology in the UF School of Teaching and Learning.
The short course will provide new tools to scientists to help them calculate how much data to collect to draw reliable and accurate conclusions. Most of the methods taught in the short courses were originally developed by research team members. The educational materials fill a chronic need in the field of research design for understandable, detailed and accurate instruction in multilevel and longitudinal study design. Near the end of the project, a webinar version of the course will be developed and offered free of charge on COURSERA as a MOOC.
The textbook and the course build upon Muller and Glueck’s efforts to make effective study design more widely available to scientists. With key collaborator, software engineer and biostatistician Sarah Kreidler, an assistant professor of radiology at the University of Colorado Denver School of Medicine , Muller and Glueck have built a free website and open source power and sample size software (samplesizeshop.org). The work has been funded by a current $2.2 million R01 grant from the National Institutes of Health.
“Better designed studies will help scientists understand the origin of disease and choose safe and effective treatments, ultimately improving the health of Americans,” explained Muller, who is a fellow of the American Statistical Association. Muller and Glueck credit the enthusiasm of audiences at invited presentations for encouraging them to develop the proposals. They highlight invited sessions at annual meetings of the American Psychological Association as important.